On power quality of variable-speed constant-frequency aircraft electric power systems
毕业设计风力发电外文文献
Abstract--The purpose of this paper is to find an innovative, high efficiency, practical and low cost control system structure with an optimized control strategy for small-scale grid-connected wind turbine with direct-driven permanent magnet synchronous generator (PMSG). This research adopts the sensorless vector control strategy based on phase-locked loop (PLL) for PMSG control, and the grid-side inverter control strategy is based on the single-phase PLL. The simulation demonstrates that the sensorless control strategy and single-phase grid-side inverter control strategy are practical solutions for grid-connected PMSG wind turbines, and they can provide both generator speed control for optimized wind power tracking and good power quality control for electricity delivered to the grid. The designed system offers many unique advantages, including simple topology, optimized control strategy, cost-effective and fast respond to grid failures.Index Terms--Maximum power point tracking (MPPT), PMSG, pulse-width modulation (PWM) converter, speed control, variable-speed wind turbine.I. I NTRODUCTIONn recent years, great attention has been paid on renewable energy sources, such as wind and solar energy. Wind energy is the most popular renewable energy source due to its relatively low cost. The overall system cost can be further reduced by optimal control of high efficiency power electronic converters to extract maximum power in accordance with atmospheric conditions [11].The wind energy conversion system based on permanent magnet synchronous generator (PMSG) is one of the most favorable and reliable methods of power generation. Reliability of variable-speed direct-driven PMSG wind turbines can be improved significantly comparing to doubly-fed induction generator (DFIG) wind turbines with gearboxes. Noise, power loss, additional cost, and potential mechanical failure are typical problems for a DFIG wind turbine because of the existence of a gearbox. The use of direct-driven PMSG could solve these problems. Moreover, low voltage ride through (LVRT) is also a big issue for DFIG because the This work was supported in part by the special funds from Beijing Municipal Education Commission.Chunxue Wen, Guojie Lu, Peng Wang and Zhengxi Li are with the Power Electronics and Motor Drivers Engineering Research Centre, North China University of Technology,Beijing,China(e-mail: wenchx1980@, lugod307@, catdapeng2008@, lzx@).Xiongwei Liu and Zaiming Fan are with the School of Computing, Engineering and Physical Sciences, University of Central Lancashire, Preston, PR1 2HE, UK (e-mail: xliu9@, zmfan@) electromagnetic relationship between the stator and the rotor is more complex than PMSG. Therefore, it’s more difficult for DFIG to solve LVRT problem safely and reliably.In a variable-speed PMSG system, vector control approach is often used to achieve nearly decoupled active and reactive power control on the grid-side inverter which is a current regulated voltage source inverter. In this way, the power converter maintains the DC-link voltage and improves the power factor of the system [1], [7], [10]. Different control methods for maximum power point tracking (MPPT) in variable-speed wind turbine generators have been discussed in [2], [4], [7].This research adopts the sensorless vector control strategy based on phase-locked loop (PLL) for PMSG control [2]. The method requires only one active switching device, i.e. insulated-gate bipolar transistor (IGBT), which is used to control the generator torque and speed so as to extract maximum wind power. It is a simple topology and low cost solution for a small-scale wind turbine because of the sensorless vector control strategy. The grid-side inverter control strategy is based on the single-phase PLL, which applies a control method in Direct-Quadrature (DQ) rotating frame to single-phase inverter and achieves superior steady state and dynamic performance [6].For small-scale wind turbine, single-phase power supply to consumers is popular. There are many control methods for single-phase inverter, such as PI controller, quasi-PR controller, etc. [5]. However, these methods can’t decouple the active power and reactive power so as to have good power control performance. Single-phase PLL method based on DQ rotating frame can well solve this problem. On the other hand, encoders are vulnerable components for wind turbines, particularly for small wind turbines, because small wind turbines experience severer vibrations than their large counterparts. The sensorless vector control opts out the encoders, and therefore the reliability of wind turbines is much improved. For these reasons, the sensorless vector control and single-phase PLL method have their unique advantages for small-scale wind turbines.This paper is structured further in following three sections. In section II, the principle of the full power back-to-back PWM converter is introduced. Then the vector control of small-scale grid-connected wind power system including sensorless control, vector control of PMSG, single-phase PLL, vector control of grid-side inverter are described in section III. Finally, in section IV, the simulation results and conclusion are given.Vector control strategy for small-scale grid-connected PMSG wind turbine converter Chunxue Wen, Guojie Lu, Peng Wang, Zhengxi Li Member IEEE, Xiongwei Liu Member IEEE,Zaiming Fan Student Member IEEEIII. T HE PRINCIPLE OF FULL POWER BACK-TO-BACK PWMCONVERTERTypical topology model of direct-driven PMSG wind turbine is shown in Fig. 1. Converters of the system adopt back-to-back pairs of pulse-width modulation (PWM) architecture. The generator-side converter controls the generator speed in order to achieve maximum capture of wind power, and the grid-side inverter controls the stability of DC-bus voltage and the power factor of the system. This topology can be a good way to improve performance, and the control method is flexible. Converters have four-quadrant operation function, which can fulfill the generator speed control anddeliver the fine quality of electricity to the grid [7], [8].Fig. 1. Topology of permanent magnet direct-driven wind power systemIII. T HE VECTOR CONTROL OF SMALL-SCALE GRID-CONNECTEDDIRECT-DRIVEN WIND POWER SYSTEM CONVERTERFig. 2 shows the back-to-back PWM voltage convertervector control block diagram. The machine-side PWMconverter controls the electromagnetic torque and statorreactive power (reactive power is often be set to 0) byadjusting the current of the d-axis and q-axis of the machine-side converter. This control mechanism helps the PMSG tooperate in variable speed, so that the wind turbine can workwith maximum power point tracking (MPPT) under the ratedwind speed. The grid-side PWM inverter stabilizes the DC-busvoltage and accomplishes active and reactive decouplingcontrol by adjusting the current of the d-axis and q-axis of thegrid-side. The grid-side PWM inverter also controls thereactive power flow to the grid, usually at unity power factorcondition.A. Sensorless control based on PLLThe speed and position control is achieved throughsensorless vector control of the machine-side converter basedon all-digital phase-locked loop. The phase-locked loop isdesigned to control the frequency of the D-Q axis voltagethrough minimizing the difference of the output voltage phaseangle and the given voltage phase angle, until the outputvoltage phase angle tracks the given voltage phase angle. Asthe phase-locked loop has frequency closed-loop trackingmechanism, the generator voltage frequency and the anglebetween d-axis voltage and rotor flux can be measured withthis characteristic, then the generator speed and rotor positionangle can be derived [2]. The control accuracy is generallygood using this method, however some problems may occurwhen the generator operates at very low speed. The windpower system often works above the cut-in wind speed, so thismethod can be applied to wind power generation system.Fig. 2.The back-to-back PWM voltage converter vector control block diagramThe actual rotor position of PMSG is indicated in the D-Q coordinate system. The estimated location for ∧θ is the d q ∧∧− coordinate system, αβ is the stationary coordinate system, as shown in Fig. 3. As the rotor position of PMSG is estimated rather than measured in the sensorless vector control system, there exists an error θΔ between the actual rotor position θ and the estimated location ∧θ. At the same time, the back-EMF (electromotive force) generated by the rotor permanent magnets generates two d-axis and q-axis components in the estimated rotor position orientation coordinates, which are expressed as sd e ∧and sq e ∧respectively. Conventional PI controller can achieve zero error control, i.e. sd e ∧or θΔ can be adjusted to zero value. The PLL sensorless vector control schematic diagram is shown in Fig. 4, and the value of sd e ∧and sq e ∧can be obtained from (1).sd sd s sd dq sq sd sq sq s sq q d sd sq di u R i L L i e dt di u R i L L i e dt ωω∧∧∧∧∧∧⎧=+−−⎪⎪⎨⎪=+++⎪⎩(1)Fig. 3. Presumed rotating coordinate systemFig. 4. Principle of PLL based sensorless vector controlIf we ignore the current differential items in (1), then wehavesd s sd q sq sd sq sq s sq d sd ˆˆˆˆˆarctan(arctan(ˆˆˆˆˆu R i L i ee uR i L i ωθω−+Δ=−=−−− (2)where sd u , sq u , sd i and sq i are the d, q-axis components of the output voltage and current of the generator stator; d L q L and s R are the inductance and resistance of the stator; ω is thegenerator electrical angular velocity of the generator; "∧" indicates estimated value.Block diagram of sensorless vector control based on digital PLL is shown in Fig. 5. The back-EMF (electromotive force) value of the estimated rotating coordinates can be obtained by calculating the three-phase voltages and currents of the PMSGstator. The calculated angle difference θΔcan be used to estimate the angular velocity through the PI controller. Then the value of the estimated angle can be obtained by integral element. Generally, the speed has considerable fluctuations using this method. Therefore it will achieve a better estimation by adding a low-pass filter (LPF), as shown in Fig. 5.∧Fig. 5. Block diagram of sensorless vector control based on digital PLLB. Vector control of PMSGIn order to study the torque control of PMSG, it is necessary to establish a mathematical model. Because q-axis leads d-axis 90° in the D-Q coordinate system, the generator voltage equation can be expressed as [8]: sd sd s sd d sq sq sq sq sq q d sd di u R i L L i dt di u Ri L L i dt ωωωψ⎧=+−⎪⎪⎨⎪=+++⎪⎩(3) The significance of various physical quantities in (3) is the same as in (1).The generator electromagnetic torque equation can be expressed as:33()22e sq d q sd sq T p i p L L i i ψ=+− (4) where p is the number of generator pole pairs, and ψ is the magnetic flux.Based on the above mathematical model, the sensorless vector control program of PMSG is established, and its controlblock diagram is shown in Fig. 6.sa i sbi Fig. 6. Sensorless vector control block diagram of PMSGGenerator rotor position and speed which are estimated by sensorless algorithm can be used in vector control. Thereference value of motor torque can be obtained by the speedcontroller. The voltage reference of generator can also be gotby current controller, and then the control signals of rectifier switching device can be obtained by a set of PWM modulation algorithms. The position and speed of generator rotor which is necessary to vector control is obtained by sensorless algorithm.C. Single-phase grid-connected PLLFig. 7 shows the block diagram of the single-phase gird-connected PLL. In order to ensure that the converter outputvoltage is in the same phase with the output current, the PLLis used to achieve unity power factor control. At the sametime, the converter also provides the angle of the referencecurrent transformation [5].Fig. 7. The block diagram of the single-phase PLLThe transformation between orthogonal a-b and D-Q reference frames can be described by trigonometric relations, which are given in (5) and (6), and the rotating reference frame is shown in Fig. 8.Fig. 8. Definition of rotating reference frame⎥⎦⎤⎢⎣⎡⎥⎦⎤⎢⎣⎡−=⎥⎦⎤⎢⎣⎡b a q d f f f f θθθθcos sin sin cos (5) ⎥⎦⎤⎢⎣⎡⎥⎦⎤⎢⎣⎡−=⎥⎦⎤⎢⎣⎡q d b a f f f f θθθθcos sin sin cos (6)Active power and reactive power equations can beexpressed as:⎩⎨⎧−=+=d q q d qq d d i v i v Q i v i v P (7) If the phase voltage and q-axis coincide, then 0=d v andv v q =, active power and reactive power equations can besimplified as:||||q dP v i Q v i =⎧⎪⎨=−⎪⎩ (8) D. The vector control strategy of the grid-side inverterFor a three phase converter, simple PI compensators designed in a D-Q synchronous frame can achieve zero steady state error at the fundamental frequency, but this method is not applicable to single-phase power converter because there is only one phase variable available in a single-phase power converter, while the D-Q transformation needs at least two orthogonal variables.In order to construct the additional orthogonal phaseinformation from the original single-phase power converter,the imaginary orthogonal circuit is developed, as shown inFig. 9. The imaginary orthogonal circuit has exactly the samecircuit components and parameters, but the current b i and the voltage b e , maintain 90D phase shift with respect to their counterparts in the real circuit- a i and a e [6].Fig. 9. Real circuit and its imaginary orthogonal circuitFrom Fig. 9, the voltage equation can be expressed as:⎥⎦⎤⎢⎣⎡−−+⎥⎦⎤⎢⎣⎡⎥⎦⎤⎢⎣⎡−=⎥⎦⎤⎢⎣⎡b b a a b a b a v e v e L i i L R i i p 11001 (9) Transforming the voltage equations into the synchronousreference frame using (5) and (6), and considering 0=d v and v v q =, we have: ⎥⎦⎤⎢⎣⎡−+⎥⎦⎤⎢⎣⎡⎥⎦⎤⎢⎣⎡−−−=⎥⎦⎤⎢⎣⎡||1//v e e L i i L R L R i i p qd q d q d ωω (10) To achieve decoupled control of active power and reactive power, the output voltage of the inverter in the synchronousreference frame can be expressed as:||)(1v i x L e d q +−=ω (11))(2q d i x L e ω+= (12)Substituting (11) and (12) into (10), system equations canbe rewritten as follows:⎥⎦⎤⎢⎣⎡+⎥⎦⎤⎢⎣⎡⎥⎦⎤⎢⎣⎡−=⎥⎦⎤⎢⎣⎡211001x x i i L R i i p q d q d (13) The active power and reactive power could be controlled by d i and q i respectively. Therefore, system control can be completed by current feedback loops as follows:))((211q q i i s k k x −+=∗(14)))((212d d i i sk k x −+=∗(15) Fig. 10 shows the control block diagram of the grid-sideinverter. It should be noted that the given active and reactive power should be set at two times of the desired values, because the imaginary circuit will not deliver any active andreactive power to the grid.θωFig. 10. The vector control block diagram of the grid-side inverterIV. S IMULATION RESULTSA simulation model in Matlab/Simulink is developed based on above theoretical analysis, and the system simulation block diagram is shown in Fig. 11.Fig. 11. The system simulation block diagramA. The simulation results of the machine-side converterIn the simulation model, the Reference speed represents the wind speed. At the beginning of the simulation (i.e. 0s), the generator speed is 4rpm and its input torque is -50Nm. At the time of 0.5s, the generator speed is 17 rpm and the input torque maintains at the value of -50Nm. At 1s, the generator speed maintains at 17 rpm and the input torque is -80Nm. The simulated waveforms are shown in Fig. 12, Fig. 13, Fig. 14, Fig. 15, respectively.It can be seen from Fig. 12 and Fig. 13, the error between the estimated rotor position angle and the actual measurement of the rotor position angle is very small in the steady state, there are some fluctuations in the dynamic response, but the rotor position angle is stabilized quickly.It can be seen from Fig. 14 and Fig. 15, there is a small error between the estimated and measured generator rotor speed at low speed. At high speed, however, the error is very small and can be ignored, and the transient response is very short. At the time 1s, the input torque increase affects thegenerator rotor speed slightly, and soon the transientdisappears.ˆ,(d e g )θθ()t sFig. 12. The estimated and measured rotor position angle(rad/s)θθ∧−(s)tFig. 13. The error of estimated and measured rotor position anglet(s)()nrpmFig. 14. The measured generator rotor speedt(s)t()esirpmnFig. 15. The estimated generator rotor speedThe simulation waveforms of the machine-side converterdemonstrate that the sensorless vector control algorithm canestimate the rotor angular position accurately, and the vectorcontrol strategy of the machine-side converter can realizegenerator speed control for the wind turbine to follow theoptimized power curve, i.e. MPPT when the wind speed isbelow rated wind speed.B. The simulation results of the grid-side inverterThe simulation results of the grid-side inverter is shown inFig. 16, Fig. 17 and Fig. 18 respectively.It can be seen from Fig. 16, when the generator outputtorque increases, the DC bus voltage is maintained constant.Fig. 17 shows that θu followsavvery well, and Fig. 18shows thatai followsavvery well.Fig. 16. The simulated DC voltageavuθuθFig. 17. The generator output A phase voltage and the grid voltage vectorangleFig. 18. The output voltage and current of the grid-side inverterFrom the simulation results of the grid-side inverter, it canbe seen that the single-phase PLL algorithm can accuratelytrack the grid-side voltage, and the vector control strategy ofthe grid-side inverter can stabilize the DC bus voltage, andcontrol the grid power factor.V. C ONCLUSIONThis research developed a power electronic converter for asmall direct-driven PMSG wind turbine using the back-to-back pulse-width modulation (PWM) topology. Thesimulation results demonstrate that1) The machine-side converter can control the generatorspeed and torque for the wind turbine to follow the optimizedpower curve, i.e. maximum power point tracking (MPPT)when the wind speed is below rated wind speed.2) The sensorless phase-locked loop (PLL) controlalgorithm can realize the vector control of the generator.3) The grid-side inverter control algorithm based on single-phase PLL can stabilize the DC bus voltage of the converter and control the grid power factor.VI. R EFERENCESPeriodicals:[1]De Tian, “The wind power technology status and development trend inthe world,” New Energy Industry, in press.[2]Ruzhen Dou, Lingyun Gu, Baotao Ning, “Sensorless control of thePMSM based on the PLL,” Electric Machines & Control Application, vol. 32, pp. 53-57, 2005.Books:[3]Qingding Guo, Yibiao Sun, Limei Wang, Modern permanent magnet ACservo motor system. China Electric Power Press, Beijing. In press.Papers from Conference Proceedings (Published):[4]S. Song, S. Kang, and N. Hahm, “Implementation and control of gridconnected AC-DC-AC power converter for variable speed wind energy conversion system,” in Proc. 2003 IEEE Applied Power Electronics Conference and Exposition, vol.1, pp.154 – 158.[5]M. Ciobotaru, R. Teodorescu and F. Blaabjerg, “A new single-phasePLL structure based on second order generalized integrator,” Record of IEEE PESC 2006, Korea, pp.1511-1516.[6]R. Zhang, M. Cardinal, P. Szczesny, M. Dame, “A grid simulator withcontrol of single-phase power converters in D-Q rotating frame,” Power Electronics Specialists Conference, vol.3, pp.1431 – 1436, 23-27 June 2002.[7]R. Esmail, L. Xu, D.K. Nichols, “A new control method of permanentmagnet generator for maximum power tracking in wind turbine application,” IEEE Power Engineering Society Meeting, vol.3, pp. 2090-2095, August 2005.[8]Yang Zhenkun, Liang Hui, “A DSP control system for the gridconnected inverter in wind energy conversion system,” IEEE ICEMS 2005 Electrical Machines and Systems, vol. 2, 2005, pp. 1050-1053, June 2005.[9]N V Suresh Kumar Srighakollapu, Partha Sarathi Sensarma, “Sensorlessmaximum power point tracking control in wind energy generation using permanent magnet synchronous generator,” Industrial Electronics 2008, 34th Annual Conference Of IEEE, Iecon , pp.2225-2230.Dissertations:[10]Cheng Lu, “The coordination control of dual PWM converter for VSCFwind power generation system,” MSc thesis, Graduate School of Chinese Academy of Sciences, Beijing, 2004.[11]Shenbing Wu, “Research on CSC-based small-scale grid-connectedwind power generation system”, MSc thesis, Hefei University of Technology, Hefei, 2009.VII. B IOGRAPHIESChunxue Wen received his BSc degree from Inner Mongolia University of Technology in 2001, MSc degree from Wuhan University in 2006, and PhD degree from the Institute of Electrical Engineering, Chinese Academy of Sciences in 2009. In 2010 he joined the Wind Energy Engineering Research Group at the University of Central Lancashire as a visiting researcher. He is currently working as a Lecturer at the Power Electronics and Motor Drivers Engineering Research Center, North China University of Technology, Beijing, China. His research interests include power electronics, wind turbine control system, converters for wind turbines.Guojie Lu received his BSc degree from North China Electric Power University in 2006. He worked in Beijing Xinhuadu Special Transformer Company from 2007 to 2009, and was responsible for the technical service transformer. At present, he is registered as a postgraduate research student at the Power Electronics and Motor Drivers Engineering Research Center, North China University of Technology, Beijing, China. His research area is wind turbine control system.The project aims to develop maximum power point tracking control algorithm for grid-connected small wind turbines.Peng Wang received his BSc degree from Taiyuan University of Technology in 2003, MSc degree from North China University of Technology in 2011. Since 2008, he has been working as a research assistant in Electrical Engineering at the Power Electronics and Motor Drivers Engineering Research Center, North China University of Technology, Beijing, China. In 2010 he joined the Wind Energy Engineering Research Group at the University of Central Lancashire as a visiting student. His research areas are permanent-magnet synchronous generator control and wind energy engineering.Zhengxi Li received his PhD degree from the University of Science and Technology, Beijing. He is the Chair Professor in Power Electronics and Motor Drivers and Head of the Power Electronics and Motor Drivers Engineering Research Center, North China University of Technology, Beijing, China. He is also Vice President of North China University of Technology. His research interests include power electronics, high voltage power transmission and distribution, intelligent transportation and renewable energy. Xiongwei Liu was born in Xiangtan, China, in 1965. He received his BEng (Hons) degree from National University of Defense Technology, Changsha, in 1985, and his MSc (Distinction) and PhD degrees from Harbin Institute of Technology in 1988 and 1991 respectively.His employment experience included Northwestern Polytechnical University, Huaqiao University, Leeds Met University, University of Hertforshire and University of Central Lancashire. His research interests include wind energy engineering, renewable energy technologies, smart grid and microgrid, and intelligent energy management system.He received a research fellowship from Alexander-von-Humboldt Foundation of Germany, which allowed him to visit Ruhr University Bochum, as a research fellow for 18 months from 1993. In 1999 he was awarded a Bronze Medal by Huo Yingdong Education Funding Council and a Model Worker Medal by the Mayor of Quanzhou, China, due to his excellent contributions in higher education when he served as a professor at Huaqiao University. He received a research fellowship from Chinese Scholarship Council, which allowed him to visit Technical University Berlin as a senior research fellow for 6 months in 2000.Xiongwei Liu is currently working as Chair Professor of Energy and Power Management and Head of Wind Energy Engineering Research Group at the University of Central Lancashire.。
PowerXL DE1 可变速启动器快速入门指南说明书
Quick Start GuideEffective February 2015New InformationCONTENTSStep 1—PowerXL DE1 Series Overview . . . . .4 Step 2—Dimensions and Power Wiring. . . . ..8 Step 3—Control Wiring.. . . . . . . . . . . . . . . . . .10 Step 4—LED Light Indicators and Faults. . . .12PowerXL DE1 VSS Quick Start GuideDisclaimer of Warranties and Limitation of LiabilityThe information, recommendations, descriptions, and safety notations in this document arebased on Eaton Electrical Inc. and/or Eaton Corporation’s (“Eaton”) experience and judgment,and may not cover all contingencies. If further information is required, an Eaton sales officeshould be consulted.Sale of the product shown in this literature is subject to the terms and conditions outlined inappropriate Eaton selling policies or other contractual agreement between Eaton and thepurchaser.THERE ARE NO UNDERSTANDINGS, AGREEMENTS, WARRANTIES, EXPRESSED ORIMPLIED, INCLUDING WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE OR MERCHANTABILITY, OTHER THAN THOSE SPECIFICALLY SET OUT IN ANY EXISTINGCONTRACT BETWEEN THE PARTIES. ANY SUCH CONTRACT STATES THE ENTIREOBLIGATION OF EATON. THE CONTENTS OF THIS DOCUMENT SHALL NOT BECOMEPART OF OR MODIFY ANY CONTRACT BETWEEN THE PARTIES. In no event will Eaton beresponsible to the purchaser or user in contract, in tort (including negligence), strict liability orotherwise for any special, indirect, incidental, or consequential damage or loss whatsoever,including but not limited to damage or loss of use of equipment, plant or power system, costof capital, loss of power, additional expenses in the use of existing power facilities, or claimsagainst the purchaser or user by its customers resulting from the use of the information,recommendations, and descriptions contained herein.The information contained in this manual is subject to change without notice.1PowerXL DE1 Series Variable Speed Starter MN040015EN–February PowerXL DE1 VSS Quick Start GuideSupport ServicesThe goal of Eaton is to ensure your greatest possible satisfaction with the operation of ourproducts. We are dedicated to providing fast, friendly, and accurate assistance. That is whywe offer you so many ways to get the support you need. Whether it’s by phone, fax, ore-mail, you can access Eaton’s support information 24 hours a day, seven days a week.Our wide range of services is listed below.You should contact your local distributor for product pricing, availability, ordering, expediting,and repairs.Web SiteUse the Eaton Web site to find product information. You can also find information on localdistributors or Eaton’s sales offices.Web Site Address/drivesEatonCare Customer Support CenterCall the EatonCare Support Center if you need assistance with placing an order, stockavailability or proof of shipment, expediting an existing order, emergency shipments, productprice information, returns other than warranty returns, and information on local distributors orsales offices.Voice: 877-ETN-CARE (386-2273) (8:00 a.m.–6:00 p.m. EST)FAX: 800-752-8602After-Hours Emergency: 800-543-7038(6:00 p.m.–8:00 a.m. EST)If you are in the U.S. or Canada, and have OI or PLC questions, you can take advantage of ourtoll-free line for technical assistance with hardware and software product selection, systemdesign and installation, and system debugging and diagnostics. Technical support engineersare available for calls during regular business hours.Drives Technical Resource CenterCall the low voltage Eaton Drives Technical Support Center should you need assistance with commissioning, trouble-shooting, parts identifications, or warranty issues.Voice: 877-ETN-CARE (386-2273),Option 2,Option 6, Option 3(8:00 a.m.–5:00 p.m. CST)e-mail:******************************PowerXL DE1 Series Variable Speed Starter MN040015EN–February 2PowerXL DE1 VSS Quick Start Guide3PowerXL DE1 Series Variable Speed Starter MN040015EN–February PowerXL DE1 VSS Quick Start GuidePowerXL DE1 Series Variable Speed Starter MN040015EN–February 4Step 1—PowerXL DE1 Series OverviewThis chapter describes the purpose and contents of this manual, the receiving inspection recommenda-tions, and the DE1 Series catalog numbering system.How to Use This ManualThe purpose of this manual is to provide you with information necessary to install, initial wiring, start up,troubleshoot, and maintain the Eaton DE1 Series. To provide for safe installation and operation of the equipment read the safety guidelines at the beginning of this manual and follow the procedures outlined in the following chapters before connecting power to the DE1Series VSS. Keep this operating manual handy and distribute to all users, technicians, and maintenance personnel for reference.If you need a full operational user manual please visit the Eaton website to obtain and download the full DE1 User Manual MN040011EN.Receiving and InspectionThe DE1 Series VSS has met a stringent series of factory quality requirements before shipment. It ispossible that packaging or equipment damage may have occurred during shipment. The DE1 series VSS is carefully packed and prepared for shipment. The devices should be shipped only in their original pack-aging with suitable packing materials. Please take note of the labels and instructions on the packaging as well as those used for unpacking. After receiving your DE1 Series VSS please check for the following:∙Before opening the package check the label info and make sure that you have received the correct DE1 VSS.∙Open the package with adequate tools and inspect the contents immediately after receipt in order to ensure that they are complete and undamaged.∙The packaging must contain the following parts:o A DE1 Variable Speed Startero An Instructional Leaflet IL040005ZUFigure 1. UnboxingPowerXL DE1 VSS Quick Start Guide5PowerXL DE1 Series Variable Speed Starter MN040015EN–February Rating LabelThe DE1 has device specific rated operation data and is listed on the nameplate on the right side of the device.The nameplate on top (Figure 4) is a simplified version that can be used to clearly identify the device if the main nameplate (Figure 3) is blocked by other devices.Figure 2. Nameplate ViewFigure 3. Nameplate A (Side Label)Figure 4. Nameplate B (Top Label)PowerXL DE1 VSS Quick Start GuideRating Label DescriptionTable 1. Label DescriptionPowerXL DE1 Series Variable Speed Starter MN040015EN–February 6PowerXL DE1 VSS Quick Start GuideCatalog DesignationThe catalog number selection/part number for DE1 VSS is subdivided into three groups.Series–Power Section–Model–(Versions)The following figure shows this in greater detail:7PowerXL DE1 Series Variable Speed Starter MN040015EN–February PowerXL DE1 VSS Quick Start GuidePowerXL DE1 Series Variable Speed Starter MN040015EN–February 8Step 2–Dimensions and Power WiringDimensions Series Frame a [in]a1 [in] b [in]b1 [in] c [in]R1 [in]R2 [in]Size (mm)(mm)(mm)(mm)(mm)(mm)(mm)DE1FS1 1.770.989.068.66 6.610.20.39(45)(25)(230)(220)(168)(5.1)(10)DE1FS2 3.54 1.979.068.66 6.610.20.39(90)(50)(230)(220)(168)(5.1)(10)Power WiringSeries Frame Line &Motor [AWG]Ground [AWG]Torque [in-lb]Size (mm 2)(Nm)DE1FS1 & FS218-618-615.051-61-6(1.7)Figure 6. DE1 Dimension ViewTable 2. DE1 DimensionsTable 3. Power Wire SizingPowerXL DE1 VSS Quick Start Guide9PowerXL DE1 Series Variable Speed Starter MN040015EN–February Power Connection ExamplesFigure 7. Power ConnectionsPowerXL DE1 VSS Quick Start GuidePowerXL DE1 Series Variable Speed Starter MN040015EN–February 10Step 3–Control WiringNote : The configurable inputs are only configurable by using the Extension Parameter Set Module (Part:DXE-EXT-SET), the Remote Keypad LED (Part: DX-KEY-LED), or the PC DrivesConnect software tool through a connection via the PowerXL Micro-Drive RJ45 to USB PC Cable (Part: DX-CBL-PC-3M0).These would need to be ordered in addition to the DE1 VSS as these are optional accessories.For the configurable mode of operations and setup of the accessories please see the DE1 User Manual MN040011EN.Figure 8.Control Terminal LayoutFigure 9. Control Terminal FunctionsPowerXL DE1 VSS Quick Start Guide11PowerXL DE1 Series Variable Speed Starter MN040015EN–February Figure 10. Default Wiring (without internal suppression filter)Figure 11. Default Wiring (with internal suppression filter)PowerXL DE1 VSS Quick Start GuidePowerXL DE1 Series Variable Speed Starter MN040015EN–February 12Step 4–LED Light Indicators and FaultsThe Run ,Status , and Fault Code LEDs will behave as follows:Run LED –Operation Signal (GREEN):∙Flashes every 2 seconds when the main voltage is applied, there is no enable input signal present at DI1 or DI2, and there are no active fault messages ∙Solid/continuous when the device is running and there is an input enable (start)signal on DI1or DI2∙No illumination when the main power is removed or there is an internal device faultStatus LED –Status Message (RED):∙Flashes with the Fault Code LED when there is an undervoltage condition ∙Solid/continuous illumination with Fault Code LED in the event of an internal communicationfault (DE1 malfunctioning)Fault Code LED –Fault Signal (RED/YELLOW):∙Cyclical Red flashing/pulse sequence with 2 second pauses observe Table 4∙Flashes Red with the Status LED when there is an undervoltage condition ∙Solid/continuous Red illumination with Status LED in the event of an internal communication fault (DE1 malfunctioning)∙Solid/continuous Yellow when DE1 VSS DC braking is activeFigure 12. LED Status Light LayoutPowerXL DE1 VSS Quick Start Guide13PowerXL DE1 Series Variable Speed Starter MN040015EN–February If the DE1 VSS has an internal communication fault (CPU fault), the green Run LED will turn off and the Status and Fault Code LEDs will both illuminate to a solid/continuous red status.NOTE : If this occurs the DE1 is faulty and will need to be replaced.Fault Messages can be reset by:∙Switching off the main voltage supply and switching it back on (cycling power)∙Switching off (removing)the input enable signal (DI1 or DI2) and switching it back onTable 4. Fault Code LED fault messagesPowerXL DE1 VSS Quick Start GuideAdditional HelpIn the US or Canada: please contact the Technical Resource Center at 1-877-ETN-CARE or 1-877-326-2273.All other supporting documentation is located on the Eaton web site atEaton1000 Eaton Boulevard Cleveland, OH 44122 USA © 2015EatonAll Rights ReservedPrinted in USAPublication No.MN040015EN February 2015Eaton is a registered trademark of Eaton Corporation.All other trademarks are property of their respective owners。
各国风电并网导则对低压电穿越的要求(ppt版)
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
镇赉风电场一期（49.5MW） 洮北风电场（98.6MW） 宝山风电场（49.5MW） 洮南风电场(99MW) 富裕风电场(15MW) 镇赉变 大安变 查干浩特风电场 (24MW) 新立风电场 (49.5MW) 白城变 大安风电场(99MW)
2004-12-14
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
1
各国风电并网导则对低电压穿越的要求
－为什么需要低电压穿越
Comparison of LVRT requirements worldwide-
Why do we need LVRT?
Voltage dips will be more severe during high wind penetration
风电机组达到切入风速时 Low Wind
风电机组额定运行时 High Wind
10
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
The impact on wind turbine of voltage dips
Unbanlance torque may influnce the stable operation of wind turbine Overcurrent of generator in transient may damage the Electronics components. Additional torque or forces may damage the mechanical components.
高压变频器使用手册——中英文版-第3章
第3章ChapterⅡ系统原理System Principle本章主要介绍PowerSmart TM变频调速系统的原理The chapter mainly introduces the principle of PowerSmart TM VariableFrequency Speed-Regulating Device3.1系统的单线原理图3.1 Single-line Schematic Diagram of the System本高压变频调速系统主要由PowerSmart TM系列变频器、远控操作箱、机旁操作箱及旁路开关柜等部分组成。
其中远控操作箱、机旁操作箱和旁路开关柜为选配设备，旁路开关柜可以采用手动或自动旁路形式，根据用户具体要求设计。
工频自动旁路系统的单线原理图如下所示：The high-voltage Variable Frequency Speed-Regulating Device is mainly composed of PowerSmart TM series drive, remote-control operation box, machine-side operation box, bypass switch cabinet and so on, among which remote-control operation box, machine-side operation box and bypass switch cabinet are matching equipments, bypass switch cabinet may be adopted manual or automatic bypass form, which is designed ac cording to concrete requirements of users. The single-line schematic diagram of power frequency automatic bypass system follows as below:3-13-2图3-1 系统的单线原理图Fig3-1 Single-line Schematic Diagram of the System注：旁路开关柜中KM2、KM3采用高压真空接触器，QF1采用高压真空断路器。
外文文献综述电能质量监测（外文原文+中文翻译）
1 Power Quality MonitoringPatrick ColemanMany power quality problems are caused by inadequate wiring or improper grounding. These problems can be detected by simple examination of the wiring and grounding systems. Another large population of power quality problems can be solved by spotchecks of voltage, current, or harmonics using hand held meters. Some problems, however, are intermittent and require longer-term monitoring for solution.Long-term power quality monitoring is largely a problem of data management. If an RMS value of voltage and current is recorded each electrical cycle, for a three-phase system, about 6 gigabytes of data will be produced each day. Some equipment is disrupted by changes in the voltage waveshape that may not affect the rms value of the waveform. Recording the voltage and current waveforms will result in about 132 gigabytes of data per day. While modern data storage technologies may make it feasible to record every electrical cycle, the task of detecting power quality problems within this mass of data is daunting indeed.Most commercially available power quality monitoring equipment attempts to reduce the recorded data to manageable levels. Each manufacturer has a generally proprietary data reduction algorithm. It is critical that the user understand the algorithm used in order to properly interpret the results.1.1Selecting a Monitoring PointPower quality monitoring is usually done to either solve an existing power quality problem, or to determine the electrical environment prior to installing new sensitive equipment. For new equipment, it is easy to argue that the monitoring equipment should be installed at the point nearest the point of connection of the new equipment. For power quality problems affecting existing equipment, there is frequently pressure to determine it. the problem is being caused by some external source, i. e., the utility. This leads to the installation of monitoring equipment at the service point to try to detect the source of the problem. This is usually not the optimum location for monitoring equipment. Most studies suggest that 80% of power quality problems originate within the facility. A monitor installed on the equipment being affected will detect problemsoriginating within the facility, as well as problems originating on the utility. Each type of event has distinguishing characteristics to assist the engineer in correctly identifying the source of the disturbance.1.1.1 What to MonitorAt minimum, the input voltage to the affected equipment should be monitored. If the equipment is single phase, the monitored voltage should include at least the line-to~neutral voltage and the neutral to-ground voltages. If possible, the Iine_to_ground voltage should also be monitored. For three-phase equipment, the voltages may either be monitored line to neutral, or line to line. Line-to-neutral voltages are easier to understand, but most three-phase equipment operates on line-to-line voltages. Usually, it is preferable to monitor the voltage line to line for three-phase equipment.If the monitoring equipment has voltage thresholds which can be adjusted, the thresholds should be set to match the sensitive equipment voltage requirements. If the requirements are not known, a good starting point is usually the nominal equipment voltage plus or minus 10%.In most sensitive equipment, the connection to the source is a rectifier, and the critical voltages are DC. In some cases, it may be necessary to monitor the critical DC voltages. Some commercial power quality monitors are capable of monitoring AC and DC simultaneously, while others are AC only.It is frequently useful to monitor current as well as voltage. For example, if the problem is being caused by voltage sags, the reaction of the current during the sag can help determine the source of the sag. If the current doubles when the voltage sags 10%, then the cause of the sag is on the load side of the current monitor point. If the current increases or decreases 10 - 20% during a 10% voltage sag, then the cause of the sag is on the source side of the current monitoring point.Sensitive equipment can also be affected by other environmental factors such as temperature, humidity, static, harmonics, magnetic fields, radio frequency interference (RFl), and operator error or sabotage. Some commercial monitors can record some of these factors, but it may be necessary to install more than one monitor to cover every possible source of disturbance.It can also be useful to record power quantity data while searchingfor power quality problems. For example, the author found a shortcut to the source of a disturbance affecting a wide area by using the power quantity data. The recordings revealed an increase in demand of 2500 KW immediately after the disturbance. Asking a few questions quickly led to a nearby plant with a 2500 KW switched load that was found to be malfunctioning.1.2Selecting a MonitorCommercially available monitors fall into two basic categories: line disturbance analyzers and voltage recorders. The line between the categories is becoming blurred as new models are developed. Voltage recorders are primarily designed to record voltage and current strip chart data, but some models are able to capture waveforms under certain circumstances. Line disturbance analyzers are designed to capture voltage events that may affect sensitive equipment. Generally, line disturbance analyzers are not good voltage recorders, but newer models are better than previous designs at recording voltage strip charts.In order to select the best monitor for the job, it is necessary to have an idea of the type of disturbance to be recorded, and an idea of the operating characteristics of the available disturbance analyzers. For example, a common power quality problem is nuisance tripping of variable speed drives. Variable speed drives may trip due to the waveform disturbance created by power factor correction capacitor switching, or due to high or low steady state voltage, or, in some cases, due to excessive voltage imbalance. If the drive trips due to high voltage or waveform disturbances, the drive diagnostics will usually indicate an over voltage code as the cause of the trip. If the voltage is not balanced, the drive will draw significantly unbalanced currents. The current imbalance may reach a level that causes the drive to trip for input over current. Selecting a monitor for variable speed drive tripping can be a challenge. Most line disturbance analyzers can easily capture the waveshape disturbance of capacitor switching, but they are not good voltage recorders, and may not do a good job of reporting high steady state voltage. Many line disturbance analyzers cannot capture voltage unbalance at all, nor will they respond to current events unless there is a corresponding voltage event. Most voltage and current recorders can easily capture the high steady state voltage that leads to a drive trip, but they may notcapture the capacitor switching waveshape disturbance. Many voltage recorders can capture voltage imbalance, current imbalance, and some of them will trigger a capture of voltage and current during a current event, such as the drive tripping off.To select the best monitor for the job, it is necessary to understand the characteristics of the available monitors. The following sections will discuss the various types of data that may be needed for a power quality investigation, and the characteristics of some commercially available monitors.I. 3 VoltageThe most commonly recorded parameter in power quality investigations is the RMS voltage delivered to the equipment. Manufacturers of recording equipment use a variety of techniques to reduce the volume of the data recorded. The most common method of data reduction is to record Min/Max/Average data over some interval. Figure I. I shows a strip chart of rms voltages recorded on a eyeIe-by-cycle basis. Figure I. 2 shows a Min/Max/Average chart for the same time period. A common recording period is I week. Typical recorders will use a recording interval of 2 - 5 minutes. Each recording interval will produce three numbers: the rms voltage of the highest I cycle, the lowest I cycle, and the average of every cycle during the interval. This is a simple, easily understood recording method, and it is easily implemented by the manufacturer. There are several drawbacks to this method. If there are several events during a recording interval, only the event with the largest deviation is recorded. Unless the recorder records the event in some other manner, there is no time~stamp associated with the events, and no duration available. The most critical deficiency is the lack of a voltage profile during the event. The voltage profile provides significant clues to the source of the event. For example, if the event is a voltage sag, the minimum voltage may be the same for an event caused by a distant fault on the utility system, and for a nearby large motor start. For the distant fault, however, the voltage will sag nearly instantaneously, stay at a fairly constant level for 3-10 cycles, and almost instantly recover to full voltage, or possibly a slightly higher voltage it. the faulted section of the utility system is separated. For a nearby motor start, the voltage will drop nearly instantaneousIy,and almost immediately begin a gradual recovery over 30 - 180 cycles toa voltage somewhat lower than before. Figure 1.3 shows a cycle-by-cycle recording of a simulated adjacent feeder fault, followed by a simulation of a voltage sag caused by a large motor start. Figure I.4 shows a Min/Max/Average recording of the same two events. The events look quite similar when captured by the Min/Max/Average recorder, while the cycle-by-cycle recorder reveals the difference in the voltage recovery profile.FIGURE 1.1 RMS voltage strip chart, taken cycle by cycle.FIGURE I. 2 Min/Max/Average strip chart, showing the minimum single cycle voltage, the maximum single cycle voltage, and the average of every cycle in a recording interval. Compare to the Fig. I. I strip chart data.Some line disturbance analyzers allow the user to set thresholds for voltage events. If the voltage exceeds these thresholds, a short duration strip chart is captured showing the voltage profile during the event. This short duration strip chart is in addition to the long duration recordings, meaning that the engineer must look at several different charts to find the needed information.Some voltage recorders have user-programmable thresholds, and record deviations at a higher resolution than voltages that fall within the thresholds. These deviations are incorporated into the stripchart, so the user need only open the stripchart to determine, at a glance, if there are any significant events. If there are events to be examined, the engineer can immediately “zoom in” on the portion of the stripchart with the event.Some voltage recorders do not have user-settable thresholds, but rather choose to capture events based either on fixed default thresholds or on some type of significant change. For some users, fixed thresholds are an advantage, while others are uncomfortable with the lack of control over the meter function. In units with fixed thresholds, if the environment is normally somewhat disturbed, such as on a welder circuit at a motor control center, the meter memory may fill up with insignificant events and the monitor may not be able to record a significant event when it occurs. For this reason, monitors with fixed thresholds should not be used in electrically noisy environments.FIGURE I. 3 Cycle-by-cycle rms strip chart showing two voltage sags. The sag on the left is due to an adjacent feeder fault on the supply substation, and the sag on the right is due to a large motor start. Note the difference in the voltage profile during recoveryMln/Ave/Max Chartt SagFIGURE I. 4 Min/Max/Average strip chart of the same voltage sags as Fig. I. 3. Note that both sags look almost identical. Without the recovery detail found in Fig. I. 3, it is difficult to determine a cause for the voltage sagscapacitor energizationI. 3. I Voltage Waveform Disturbances.Some equipment can be disturbed by changes in the voltage waveform. These waveform changes may not significantly affect the rms voltage, yet may still cause equipment to malfunction. An rms-onIy recorder may not detect the cause of the malfunction. Most line disturbance analyzers have some mechanism to detect and record changes in voltage waveforms. Some machines compare portions of successive waveforms, and capture the waveform if there is a significant deviation in any portion of the waveform. Others capture waveforms if there is a significant change in the rms value of successive waveforms. Another method is to capture waveforms if there is a significant change in the voltage total harmonic distortion (THD) between successive cycles.The most common voltage waveform change that may cause equipment malfunction is the disturbance created by power factor correctioncapacitor switching. When capacitors are energized, a disturbance iscreated that lasts about I cycle, but does not result in a significant change in the rms voltage. Figure 1.5 shows a typical power factorFIGURE 1.6 RMS stripcharts of voltage and current during a large current increase due to a motor start downstream of the monitor point.1.4Current Waveshape DisturbancesVery few monitors are capable of capturing changes in current waveshape. It is usually not necessary to capture changes in current waveshape, but in some special cases this can be useful data. For example, inrush current waveforms can provide more useful information than inrush current rms data. Figure I. 7 shows a significant change in the current waveform when the current changes from zero to nearly 100 amps peak. The shape of the waveform, and the phase shift with respect to the voltage waveform, confirm that this current increase was due to an induction motor start.Figure 1.7 shows the first few cycles of the event shown in Fig.1.6.I.5HarmonicsHarmonic distortion is a growing area of concern. Many commercially available monitors are capable of capturing harmonic snapshots. Some monitors have the ability to capture harmonic strip chart data. In this area, it is critical that the monitor produce accurate data. Some commercially available monitors have deficiencies in measuring harmonics. Monitors generally capture a sample of the voltage and current waveforms, and perform a Fast Fourier Transform to produce a harmonic spectrum. According to the Nyquist Sampling Theorem, the input waveform must be sampled at least twice the highest frequency that is present in the waveform. Some manufacturers interpret this to mean the highest frequency of interest, and adjust their sample rates accordingly. If the input signal contains a frequency that is above the maximum frequency that can be correctly sampled, the high frequency signal may be u aliased, ” that is, it may be incorrectly identified as a lower frequency harmonic. This may lead the engineer to search for a solution to a harmonic problem that does not exist. The aliasing problem can be alleviated by sampling at higher sample rates, and by filtering out frequencies above the highest frequency of interest. The sample rate is usually found in the manufacturer’ s literature, but the presence of an antialiasing filter is not usually mentioned in the literature.I. 6 SummaryMost power quality problems can be solved with simple hand~tools and attention to detail. Some problems, however, are not so easily identified, and it may be necessary to monitor to correctly identify the problem. Successful monitoring involves several steps. First, determine if it is really necessary to monitor. Second, decide on a location for the monitor. Generally，the monitor should be installed close to the affected equipment. Third, decide what quantities need to be monitored, such as voltage, current, harmonics, and power data. Try to determine the types of events that can disturb the equipment, and select a meter that is capable of detecting those types of events. Fourth, decide on a monitoring period. Usually, a good first choice is at least one business cycle, or at least I day, and more commonly, I week. It may be necessary to monitor until the problem recurs. Some monitors can record indefinitely by discardingolder data to make space for new data. These monitors can be installed and left until the problem recurs. When the problem recurs, the monitoring should be stopped before the event data is discarded.After the monitoring period ends, the most difficult task begins — interpreting the data. Modern power quality monitors produce reams of data during a disturbance. Data interpretation is largely a matter of experience, and Ohm’ s law. There are many examples of disturbance data in books such as The BMI Handbook of Power Signatures, Second Edition, and the Dranetz Field Handbook for Power Quality Analysis.1量监测里•曼许多电能质量问题所造成的布线不足或不当的接地。
汽车变速器外文翻译
外文翻译Auto TransmissionFirst, an overview of automotive transmission and the development trendAutomobile available more than a century, especially from the mass production of motor vehicles and the automotive industry since the development of large, Car has been the economic development of the world for mankind to enter the modern life and have had a tremendous impact on the immeasurable, The progress of human society has made indelible contributions to the great, epoch-making set off arevolution. From From the vehicle as a power plant using internal combustion engine to start, auto transmission has become an important component. Is Generation is widely used in automotive reciprocating piston internal combustion engine with a small size, light weight, reliable operation and the use of The advantages of convenience, but its torque and speed range of smaller changes, and complex condition requires the use of motor vehicles Traction and the speed can be considerable changes in the scope. Therefore, its performance and vehicle dynamics and economy of There are large inter-contradictions, which contradictions of modern automotive internal combustion engine by itself is insoluble. Because Here, in the automotive power train set up the transmission and main reducer in order to achieve the purpose of deceleration by moment. Speed The main function of performance: ⑴ change gear ratio of motor vehicles, and expand the wheel drive torque and rotational speed of the Fan Wai, in order to adapt to constantly changing driving cycle, while the engine in the most favorable conditions within the scope of work; ⑵no change in the direction of engine rotation, under the premise of the realization of cars driving back; ⑶the realization of the free, temporary Interruption of power transmission, in order to be able to start the engine, idling, etc.. V ariable-speed drive transmission by the manipulation of institutions and agencies. Change the transmission ratio by way of transmission is divided into There are class-type, non-stage and multi-purpose three. Have class most widely used transmission. It uses gear drive, with a number of transmission ratio setting. Stepless transmission Continuously V ariable Transmission (CVT) transmission ratio of a certain The framework of multi-level changes may be unlimited, there is a common type of power and torque (dynamic fluid-type) and so on. Continuously V ariable Transmission Transmission development is the ultimate goal, because only it can make the most economical engine in working condition Can provide the best vehicle fuel economy and optimal power in order to provide the most comfortable By the feeling. Today's CVT is a typical representative of the CVTand IVT, however as a result of the reliability of Poor, non-durable materials and high cost issues, development is not very good. Comprehensive refers to transmission torque converter and the mechanical components have the level of transmission variable hydraulic mechanical Speed, the transmission ratio can be between the maximum and minimum range of a few discontinuous change for no class, but its Significantly lower transmission efficiency than the efficiency of gear drives. 2 By manipulation, transmission control type can be divided into mandatory, automatic and semi-automatic control to manipulate three - Species . Mandatory on the driver to manipulate the direct transmission gear shift control for the majority of motor vehicles used Also known as Manual Transmission Manual Transmission (MT). Automatic transmission control selection of the transmission ratio (transmission) is carried out automatically. Just add the driver to manipulate Speed pedal, you can control the speed, also known as Automatic Transmission Automatic Transmission (A T). It is According to the speed and load (throttle pedal travel) for two-parameter control, stall in accordance with the above two Parameters to automatically take-off and landing.A T and MT in common is that they are level transmission, but A T According to the speed of the speed shift automatically, you can eliminate the manual transmission "setback" of the shift feel. However, A T also have many drawbacks, such as body complex, mechanical efficiency is not high, high cost, reliability and control Sensitivity remains to be increasing . AMT (Automated Mechanical Transmission) is in the traditional dry clutch and manual transmission gear based on the transformation of form, mainly to change the part of the manual gearshift control. That is, the overall structure of the MT cases the same switch to electronically controlled automatic transmission to achieve. Semi-automatic control, there are two forms of transmission. A number of stalls is a common automatic control, and the remaining stalls manipulated by the driver; the other is pre-style, that is, pre-selected pilot stalls, the clutch pedal in the down or release the accelerator pedal, the for retirement or an electromagnetic device to shift the hydraulic device. In recent years, with advances in vehicle technology and road traffic density increased, the performance requirements of the transmission is also getting higher and higher. A large number of automotive engineers in improving the performance of automobile transmission study a great deal of effort devoted to the rapid transmission of technology development, such as A T, AMT, DCT, CVT and the emergence of IVT.2003 Hyundai A T, AMT, DCT, CVT forum reached a consensus on the following:in the next Development, MT will continue to be the most widely used automotive transmission, AMT will increase the proportion of the application, A T also Will occupy a large market share, CVT's use of certain limitations, can only be due to a number of small displacement Car, DCT (dual clutch transmission) will also be the budding growth. From 2003 to now, vehicle speed Thedevelopment of devices and the forum basically the consensus reached by consensus. By comparing the analysis, the traditional mechanical transmission is still the most widely used vehicle change Speed. Although it has many shortcomings, such as shifting the impact of large, bulky, cumbersome to manipulate and so on; however, it also There are many advantages, such as high transmission efficiency, reliable operation, long life, manufacturing processes mature and low cost. Therefore, if we can improve the mechanical transmission of the above-mentioned shortcomings, it still has great room for development.Second, Manual Transmission Fault DiagnosisManual transmission at the beginning of the fault diagnosis prior toFailure to confirm from other parts is not: to check the tire And wheels, to confirm the normal tire pressure, and the wheel is flat V alue of; to confirm instead of noise and vibration from the engine. Clutch , And steering and suspension, etc..(A), skip file1. PhenomenonV ehicle acceleration, deceleration, climbing or severe vehicle vibration, the gear lever neutral position automatically jump.2. Reasons① self-locking device of the ball did not enter the grooves or linked file does not meet the full-gear tooth meshing long;② self-locking device worn groove ball or serious, self-locking spring is too soft or broken fatigue;③ gear along the direction of tooth wear as a long cone-shaped;④ one or two too松旷shaft bearing, so that one or two three-axis and the crankshaft axis of the heart or different transmission and clutch shell shell bonding plane of the vertical axis the relative change in the crankshaft;⑤ Second Gear axis often axial or radial gap is too large;⑥ the axis of axial or radial gap is too large.3. Fault diagnosis and troubleshootingJump to file stalls Unascertained: After taking heat the entire vehicle, increase the use of continuous, slow approach to road test each file is determined.Will jump to the gear lever hanging file stalls the engine off, transmission cover removed carefully to observe the mating dance gear case file.① engagement does not meet the length, then the resulting fault;② to reach a total length of engagement, should continue to check;③ check mating wear parts: wear into a cone, then failure may be caused by;④ check b-axis of the gear profile and the axis of the axial and radial clearance, clearance is too large, then failure may be caused by;⑤ check self-locking devices, locking devices, if only a very small dynamic resistance, and even feel the ball is not plugged groove (the transmission cover caught in the vice, the hand-shaking shift stroke), the fault for the bad performance of self-locking ; Otherwise, the fault for the clutch and gearbox shell bonding plane and the vertical axis of the crankshaft caused by changes.(B), arbitrary files1. PhenomenonTechnical condition in the clutch normal circumstances, transmission at the same time put up or two files linked to the need to stall, the results linked to other stalls.2. Reasons① interlocking device failure: if the fork shaft, pin or interlocking interlocking ball too much wear and tear, etc.;② the bottom of the arc gear face wear and tear is too large or fork axis of the allocated blocks wear groove is too large;③ball pin gear lever broken or the ball-hole, ball松旷wear too. In short arbitrary file transmission is mainly due to institutional failure manipulation.3. Fault diagnosis and troubleshooting① linked to the need to stall, the results linked to the other stalls: rocking gear lever, to check their point of view before, if in excess of the normal range, while the lower end of failure by the gear lever ball pin and the positioning groove ball with or松旷, the ball is too large holes caused by wear and tear. Swung shift 360 °, compared with a broken pin.② If the pendulum angle to normal, still not on, or linked to more than picking file, then the lower end of failure by the gear lever away from the limitations arising from the groove in (due to break away from the bottom of the arc-shaped guide groove face wear and tear or wear).③ At the same time linked to the two files: the fault caused by the interlocking device failure.(C), the difficulties linked to files1. PhenomenonClutch technical condition, but can not be linked smoothly linked file into the stalls, often percussive sound gear.2. Reasons① synchronizer failure;② Bending fork shaft, locking the spring strong, ball injury, etc.;③ a shaft or a spline shaft bending injury;④ inadequate or excessive gear oil, gear oil does not meet the specifications.3. Fault diagnosis and troubleshooting①Synchronizer check whether the fall to pieces, cone ring is conical spiral groove wear, whether worn slider, spring is too soft, such as elastic.② If the Synchronizer normal, check whether the bending of a shaft, spline wear is severe.③ check whether the mobile axis normal fork.(D), abnormal sound transmission1. PhenomenonTransmission refers to transmission work abnormal sound when the sound is not normal.2. Reasons1) abnormal sound gearGear wear off very thin gap is too large, the impact of running in; bad tooth meshing, such as the repair did not replace the gear pairs. New and old gear with the gear mesh can not be correct; tooth metal fatigue spalling or damage to individual teeth broken; gear and the spline shaft with松旷, or the axial gear clearance is too large; axis caused by bending or bearing松旷space to change gears.2) Bearing ringSerious bearing wear; Bearing (outer) ring with the journal blocks (holes) with the loose; Ball Bearing Ma break-up or a point of ablation.3) ring made for other reasonsSuch as the transmission within缺油, lubricants have been thin, too thick or quality deterioration; transmission into the foreign body inside; some loose bolts fastening; odometer or the odometer shaft ring gear, such as fat.3. Troubleshooting①transmission issued metal dry friction sound, which is缺油and the poor quality of oil. Refueling and inspection should be the quality of oil, if necessary, replacement.② for moving into a file if the sound obvious, namely, the profile of gear tooth wear; If the occurrence of cyclical noise, while damage to individual teeth.③when the ring gap, and riding the clutch pedal under the noise disappeared after the general axis is a before and after the bearing or regular engagement ring gear; if any files are changed into the ring, after more than two-axis bearing ring.④transmission occurs when a sudden impact the work of sound, most of the tooth was broken and should be removed timely transmission inspection cover to prevent mechanicaldamage.⑤moving, only for transmission of a file into the ring gear made in the above-mentioned good premise, it should check with improper gear mesh, if necessary, should be re-assembling a pair of new gear. In addition, it may be synchronizer gear wear or damage should be repaired or replaced depending on the circumstances.⑥ when shifting gear ring made of impact, it may be the clutch or the clutch pedal can not be separated from stroke is incorrect, damaged synchronizer, excessive idling, gear improperly adjusted or tight-oriented, such as Bush. In such cases, to check whether the separation of the clutch, and then adjust the idle speed or the gear lever, respectively, the location, inspection-oriented with the bearing bushing and separation tightness.If excluded from the above examinations, the transmission is still made ring, should check the shaft bearings and shaft hole with the situation, bearing the state of their own technology, etc.; as well, and then view the odometer shaft and ring gear is made and, if necessary, be repaired or replacement.(E), transmission oil1. PhenomenonAround the transmission gear lubricants, transmission gear box to reduce the fuel can be judged as lubricant leakage.2. Reasons and troubleshooting① improper oil selection, resulting in excessive foam, or the volume too much oil, when in need of replacement or adjust the lubricant oil;② side cover is too loose, damaged gaskets, oil seal damage, damage to seals and oil seals should be replaced with new items;③ release and transmission oil tank and side cover fixed bolts loosening, tightening torque should be required;④ broken gear-housing shell or extended wear and tear caused by oil spills, must be replaced;⑤ odometer broken loose gear limit device must be locked or replaced; gear oil seal oil seal oil should be replaced.Third, the maintenance manual gearboxSantana is now as an example:Santana used to manually synchronize the entire, multi-stage gear transmission, there are four forward one block and reverse gear. Block are forward-lock synchronizer ring inertial, body-wide shift synchronizer nested engagement with a reasonable structure, the layout of a compact, reliable, long life and so on. However, if the use and maintenance is not the right way to do so, failure mayoccur at any time.The proper use of Synchronizer:1, the use of addition and subtraction block off both feet. Block addition and subtraction, if the clutch with one foot, then the speed at the time of addition and subtraction block must be correct, the timing should be appropriate and, if necessary, to addition and subtraction can be blocked off both feet, so that addition and subtraction method can reduce the block with Gear speed difference between the circumference, thereby reducing wear and tear Synchronizer to extend the life of Synchronizer.2, prohibited the use of tap-shift gear lever when the method (that is, a push of the operation of a song). Hand should always hold down the shift, this can greatly reduce the synchronizer sliding lock Moreton Central time and reduce wear and tear.3, no state in the gap off the use of force挂挡synchronizer start the engine. Moment of inertia as a great engine, the friction torque Synchronizer also small, so the time synchronization process is very long, so that lock ring temperature increased sharply, it is easy to burn synchronizer.4, is strictly prohibited by synchronizer clutch instead of the initial (that is, the use of non-use of the clutch friction synchronizer start挂挡role), control speed and braking.The correct use of lubricants:Santana at the factory, the transmission has been added to the quality of lubricating oil, under normal circumstances, the level of the transmission lubrication need to be checked. However, when normal travel 100,000 kilometers 10,000 kilometers -20 after the first lubricating oil must be replaced. Santana grade lubricants used in transmission as follows: Gear Oil API-GLA (MIL-L2105), SAE80 or SAE80W-90 grade汽车变速器一、汽车变速器概述及发展趋势汽车问世百余年来，特别是从汽车的大批量生产及汽车工业的大发展以来，汽车己为世界经济的发展、为人类进入现代生活，产生了无法估量的巨大影响，为人类社会的进步作出了不可磨灭的巨大贡献，掀起了一场划时代的革命。
约翰迪尔船用柴油发动机说明书
The powerful and reliable choice2Nothing Runs Like A Deere™John Deere PowerTech™ engines are as powerful in the water asthey are on the land. Our marine propulsion and generator engines share the same reputation for performance and reliability that their agricultural and industrial counterparts have enjoyed for decades. They are also backed by a vast service network that will keep you operating — no matter where you go.When you choose John Deere, you get the support of one of the strongest engine and equipment companies in the world. See for yourself why more vessels are being powered by John Deere.Clean engines — clean airWith John Deere PowerTech engines, everything runs clean and efficiently — above and below deck. John Deere marine engines offer closed crankcase vents that eliminate undesirable gases in the engine room and keep the bilge clean.John Deere also protects the air outside your boat by complyingwith international, European, and United States emissions standards for regulated vessels. John Deere meets Environmental Protection Agency (EPA) Marine Tier 3 emissions regulations with a complete line of PowerTech engines for newly constructed vessels as well as repowered boats.–E PA Tier 3 regulations for vessels flagged in the United States–E uropean Union Nonroad Mobile Machinery (NRMM – 97/68/ECas amended), whose standards are also recognized by the CCNR for sailing on the Rhine–E uropean Union Recreational Craft Directive (RCD – 94/25/ECas amended)–E missions certified engines over 130 kW (174 hp) meet regulations set out in Annex VI of the International Maritime Organization (IMO) MARPOL convention. Engine International Air Pollution Prevention (EIAPP) certificates issued by the U.S. EPA or American Bureau of Shipping (ABS) are available for select engine models. Visit your John Deere dealer for details.6.8L 115 – 298 kW 154 – 400 hp 9.0L 213 – 410 kW 285 – 550 hp4.5L 60 – 168 kW 80 – 225 hp 13.5L 272 – 559 kW 365 – 750 hp4Marine applicationsAuxiliary power that’s ready when you areJohn Deere PowerTech™ engines are engineered to run vessel auxiliariessuch as pumps, winches, deck cranes, and hydraulics. With displacementsfrom 4.5 liters to 13.5 liters and power ratings from 74 to 448 kW (99 to600 hp), fitting your application has never been easier. We also offer achoice of options and accessories.6Generator drive engines — the strong silent typeFor reliable power from 40 to 416 kW (54 to 558 hp), John Deeregenerator drive engines deliver quiet, smooth operation that never letsyou down. You may even forget they are aboard until you turn on thelights or plug in an appliance. This quiet reliability is why John Deere isa preferred provider of generator drive engines worldwide. They areavailable in 1500 rpm for 50 Hz and 1800 rpm for 60 Hz configurations.Quiet operation and low vibrationWe strive to design engines that go almost unnoticed. This is why allthe moving parts are dynamically balanced. The torque available atlow rpm helps with fast load response.–W ater-cooled exhaust manifold for cooler, quieter performance–E ngine isolators with optional mounting supports–A ll 4-cylinder models have internal balance shafts to eliminate vibrationPowerTechradiator-cooledgenerator driveengines40 – 416 kW54 – 558 hpMarine Engine Generator Drive Power Ratings89Marine applicationsQualified John Deere techniciansA worldwide support networkThe proven John Deere dealer network of over 4,000 service locations is prepared to fully support you and your engines. From around the globe, John Deere engine distributors and service dealers are your best source for engine service, knowledge, and parts. Our dealers keep John Deere maintenance and repair parts in stock to get you back on the water quickly. Also, John Deere’s worldwide parts distribution Search parts by model number, part number, or keyword ake advantage of local John Deere dealer pricing and inventory et access to parts catalogs with product images Fast. Convenient. Online. Customer supportThis literature has been compiled for worldwide circulation. While general information, pictures and descriptions are provided, some illustrations and textmay include finance, credit, insurance, product options and accessories NOT AVAILABLE in all regions. PLEASE CONTACT YOUR LOCAL DEALER FOR DETAILS.John Deere reserves the right to change specification and design of all products described in this literature without notice./marine DSWC20 Litho in U.S.A. (15-10)。
蒂奴家庭终端产品系列说明说明书
Trane Familyof Terminal Products It’s time to take another look at terminal.As your partner, Trane understands it takes more than a concept to design an effective HVAC system. Between cost and code compliance – not to mention comfort, acoustics and efficiency – the conflicting interests can be challenging to satisfy.The Trane family of terminal products has been redesigned from the inside out, with innovative high efficiency upgrades guaranteed to fulfill virtually any building’s requirements without compromising your needs.Now, the industry’s only terminal units with an exclusive Trane electroni-cally commutated motor (ECM) standard on all products, integrated with the industry’s first factory programmed variable speed controller, means a Single Zone VAV solution that improves efficiency by up to 66%.Problem? Solved.UniTrane Fan CoilF an coil is an in-room unit composed of a fan and chilled or hot water coils. Applications include hotels, condominiums, dormitories and apartments.F orce-Flo™ cabinet heaters are a high capacity, forced air fan coil unit for entryways and corridors in large office buildings, schools, hospitals and dormitories.Trane Unit VentilatorU nit ventilator operates on the same principles as a fan coil, but are tailored specifically for schools with a sturdy institutional design and an integrated airside economizer. Applications include schools, as they are an especially effective solution for classroom renovation projects.Trane Blower CoilB lower coil is a light duty air handler for chilled water or refrigeration systems with ducted air distribution. Applications include schools, hospitals, offices, retail stores and stadiums.Frequently Asked QuestionsSingle Zone VAVBuilding Life Trane knows that careful attention to the unique needs of a building can improve the life of equipment, controls and HVAC systems.This solutions-oriented commitment to delivering exceptional performance fosters an environment that has a positive impact on the lives of the people within it.What is Single Zone VAV?What are the applications?Why is it better than a Constant Volume system?How does Single Zone VAV impact operating cost?How does a Single Zone VAV system improve comfort for buildingoccupants? How can I get a Single Zone VAV system?Single Zone Variable Air Volume (VAV) is a high efficiencysystem in which the motor speed and air volume automaticallyadjust in response to a space’s needs.Spaces where occupancy varies. Examples include classrooms,office buildings, gymnasiums, dormitories and barracks.Single Zone VAV offers substantial operating savings becausea high efficiency motor driven, variable fan speed can be themost energy efficient way to address partial load conditions.Single Zone VAV lowers operating costs because of the ef-ficiency gains that come from the ability to operate at lowspeeds for partial loads.Temperature Stability – Variable speed technology gradu-ally changes fan speed, which reduces temperature swings.Quiet Operation – Variable speed units run at the lowestfan speed necessary, and move up and down slowly betweenspeeds. This soft ramp capability means fewer audible changesand a substantial 5 to 8 decibel reduction in system noise.Dehumidification – Operating at lower speeds for more timeimproves dehumidification, a key factor for IAQ and comfort.Trane ECM terminal units integrated with the UC400Unit Controller offers the only factory commissioned Single Zone VAV solution in the industry.T T EA OA RA space Single Zone VAV System ConfigurationIn a Single Zone VAV system, thetemperature sensor in the zone isused to vary the air temperature andthe air volume in order to maintainthe desired set point.Terminal TransformedTerminal units shouldn’t be an industry afterthought. Trane understands they are a critical system component, and careful consideration was given to every design and performance specification to transform our familyof terminal solutions into a high performance way to drive a building’s efficiency.Whether you’re concerned with occupant comfort or system design, Trane has the answer.Innovation in ECMT erminal products were upgraded from conventional PSC motors to our exclusive new EC motors, making Trane the only manufacturer currently offering ECM as standard technology.Real Time FeedbackVelociTach TM is our EC motor control board that features a Trane exclusive LED screen to provide real time feedback to installers and maintenance staff. This eliminates the inconvenience of using a separate service tool.Control Board Benefits• Enhances serviceability and improves response time for maintenance staff • Allows maintenance to monitor performance and maximize efficiency • Eliminates cost of additional computer hardware and software• Reduces the time needed to balance the unit during installation.Even the most skillfully engineered solutions maynever deliver their full potential without controlsdesigned to leverage the system’s capabilities.Trane developed innovative control algorithmsthat maximize the performance and efficiency foreach of our units under all operating conditions.Only Trane terminal products are available withfactory mounted, wired and programmed Tracer TMunit controllers, providing unmatched systemintegration and performance optimization.Tracer UC400 Unit ControllerThe UC400 Single Zone VAV controller minimizesfan speed and energy use by delivering only theairflow necessary to address the space load.This programmable controller’s functions include:• Random Start• Warm-up, Pre-cool• Freeze Avoidance• Built-in Dehumidification• Auto Fan Speed Adjustment• Discharge Air T emperature ControlControlled CostsThe lowest total cost of ownership in the industrymakes the new Trane high efficiency terminal units a value-added asset to any building’s HVAC system.Advanced ControlsSeparation Innovation We separated the Trane EC motor from the VelociT ach TM motor control board, andadded an LED display andmanual interface.This delivers the conve-nience of a visual statusreport and the ease ofpush button adjustments,facilitating optimal per-formance and simplifyingserviceability.Cost perUnitCost per Install Cost to Operate Cost to MaintainUnderstanding the UpgradesThe terminal products upgrade is more revolution than redesign. Ratherthan incremental improvements, we took a technological leap forward andelevated the industry standard for this product class.We leveraged the synergy of the new technology suite to produce dramaticimprovements in ease of installation, cost of ownership, acoustics andtemperature control.Streamlined InstallationUnits, unit controls and piping packages are installed, configured andtested during manufacture. A factory commissioned system makes job siteinstallation a streamlined, single point power, plug and play process andensures long term, trouble free operation.Quiet OperationSoft ramp technology slowly ramps motor speeds up and down to addressthe space load and eliminates the distracting noise associated with unitsturning on and off. And because the moderated air flow achieves the samecomfort levels as running at full capacity, variable units are 5 - 8 decibelsquieter than traditional three speed models.Continuous ComfortInnovative tempering algorithms in the UC400 controller eliminates the typical temperature variations that cause occupants discomfort. This dis-charge air temperature control means your space reaches the desired set point more quickly and the temperature maintenance is more stable.Superior PerformanceECM is a high efficiency, programmable motor technology. Motors require less maintenance, are more reliable and have a longer service life. They can be performance optimized at any speed, dramatically increasing energy efficiency over conventional three speed PSC motors.ECM has significant efficiency gains over PSCMotor Size, HPTrane asked customers what they need in a ter-minal unit. Then, we built their feedback into thenew designs.The result is a flexible line of high efficiencysolutions that meet all your new construction andrenovation needs. No compromise necessary.Universal CompatibilityTrane terminal units offer flexible solutions forvariable speed operation through compatibilitywith existing thermostats and controllers.The open communication protocol of the Tracer TMUC400 supports seamless integration at the build-ing system or equipment level through BACnetcommunication.With a smart controls retrofit solution, there areno limits to what Trane can do for you.No Compromise SolutionLighten Your Load Trane developed an exclusive application to reduce the nameplate Full Load Amps (FLA) of standard size EC motors. This eliminates wiring limitations common with renovations, bringing the benefits of Single ZoneVAV to older buildings.The features you want. The technology you need.T otal Costof OwnershipEfficiency Serviceability Flexibility Acoustics Comfort Trane Exclusive ECM StandardAdvanced Controls Plug & Play Soft Ramp Discharge Air T emperature Control Real Time Feedback l l l l l l l ll l l l l ll ll l l ll l l l l ll Reduced FLAl l You Asked For...© 2013 Trane All rights reservedUNT-SLB030-EN August 30, 2013 We are committed to using environmentally conscious print practices that reduce waste.Ingersoll Rand (NYSE:IR) is a world leader in creating and sustaining safe, comfortable and efficient environments in commercial, residential and industrial markets. Our people and our family of brands—including Club Car®, Ingersoll Rand®, Schlage®, Thermo King® and Trane®—work together to enhance the quality and comfort of air in homes and buildings, transport and protect food and perishables, secure homes and commercial properties, and increase industrial productivity and efficiency. We are a $14 billion global business committed to sustainable business practices within our and for our customers. For more information, visit . Visit /TerminalTech for more information.。
铁道科技名词
铁道科技名词（车钩缓冲装置）压缩与拉伸(coupler and draft gear) running-in and running-out （电话）用户(telephone) subscriber（复原）摇枕swing bolster（给水）减压阀(pressure) reducing valve（货车）上开门upward swing door（货车）下开门downward swing door（货物）计费重量charged weight（机车）牵引梁draw beam（客车）摆门spring butt rocking door（客车）隔门partition door（客车）脚蹬门vestibule entrance door（客车）摇门swing door（客室）通道aisle, gangway（列车制动）溜放试验coasting braking test（桥涵）拱圈arch ring（塞入门）导轮door guide wheel（隧道）拱圈arch（无线电）干扰测量仪(radio) interference meter（增压器）压气机blower（制动）柱塞spool（制动缸压力）保持阀retaining valve（自动）开闭器switch circuit controller（阻抗）匹配变压器impedance matching transformer4毫米锁闭check 4mm opening of a switch pointH型柴油机H-type diesel engineK值试验test for K value of complete carL/V比值L/V ratioS形辐板S-type wheel plate, S-plateU形桥台U-shaped abutmentV形桥墩V-shaped pierV型柴油机V-type diesel engineω型燃烧室toroidal combustion chamber矮侧板low side矮端板low end矮型信号机dwarf signal爱车点car caring point安全标志safety mark, safety symbol, safety indicator安全地点safety place安全电路vital circuit, safety circuit安全电压safety voltage安全阀safety valve安全防护设备safety protection equipment安全技术措施safety technical measures安全教育safety education安全接点safety contact, power off contact安全距离safety distance安全帽safety cap, safety helmet安全设备试验test on safety equipments安全绳safety rope, safety strap安全梯emergency staircase, fire escape安全网safety net安全线catch siding安全性safety安全用电safety in utilizing electric energy安全炸药safety explosion, explosive charge, safety explosive 安全装置safety device, safety equipment安装角stagger angle按键电话机key pad telephone set按键开关button switch, key switch按键式拨号盘key pad按钮push-in button按钮表示button indication暗挖法subsurface excavation method凹底平车depressed center flat car扒碴机crib ballast removers拔叉poking fork拔道track lining拔道机track lining machine拔道器track lining tool拔起高度height of lifting, lifting height, ascent of elevation白点flake crack, shatter crack, small nucleus fissure白水表行车running without water in gage白噪声测试器white noise test set百叶窗louver百叶窗油缸oil cylinder of shutter摆滚振动rock-roll vibration摆块centering block摆块吊centering block hanger摆式车体pendulum type car body摆式减振器pendulum damper扳道电话switchman’s telephone扳道房switchman’s cabin班长台chief operator’s desk板梁plate girder板梁式钢结构plate girder type steel structure板桥slab bridge板式车架plate frame板式轨道slab-track板式橡胶支座laminated rubber bearing板桩sheet pile办理闭塞blocking半补偿链形悬挂semi-auto-tensioned catenary equipment半穿式桥half through bridge, midheight deck bridge半堤半堑part-cut and part-fill section, cut and fill section半叠片机座semi-laminated frame半段效应half section effect半分开式扣件semi-separated rail fastening, mixed holding fastening半分配制会议电话telephone conference of semi-distribution system半径杆radius bar, radius rod半路堑式明洞part cut-type open cut tunnel, part cut-type tunnel without cover, part cut-type gallery半湿喷混凝土half wet shotcreting半湿喷混凝土机half wet shotcreting machine半双工half-duplex operation半双工传输half-duplex transmission半双工无线电通信semi-duplex radio communication半拖车semi-trailer半循环交路semi-loop routing半压力式涵洞inlet submerged culvert半夜灯evening lamp半自动闭塞semi-automatic block system半自动闭塞机semi-automatic block machine半自动闭塞联系电路liaison circuit with semi-automatic blocks半自动化驼峰semi-automatic hump半自动化驼峰系统semi-automatic hump yard system半自动作业semi-automatic operation by route棒式车架bar frame棒式绝缘子strut insulator, rod insulator包/分组packet, package包层直径cladding diameter包裹parcel包间式卧车(corridor) compartment (type) sleeping car包交换packet switching包交换网packet switching network包式终端packet mode terminal包装/拆器packet assembler/disassembler, PAD包装储运图示标志pictorial markings for handling of packages包装运输试验transporting test for package薄壁筒体结构thin-shelled tubular structure饱和蒸汽室saturated chamber保安器protector保持位suppression, maintaining position, holding position保护地线protective earth wire保护电路protective circuit保护电容器protective capacitor保护阀protective valve保护接地protective grounding保护区段overlap protection block section保护套管protection sleeve保护线protective wire保护线用连接线crossbond of protective wire保温集装箱thermal container保温运输insulated transport保险带safety belt保险费insurance charge保压停车stopping at maintaining position报警alarm报警保护系统alarm and protection system报头header报头开始信号start-of-heading signal报文message抱缸piston seizure抱轴式牵引电动机axle hung traction motor, nose suspension traction motor抱轴瓦axle suspension bush抱轴悬挂装置suspension bearing抱轴轴承axle hung bearing, suspension bearing爆破排淤blasting discharging sedimentation, silt arresting by explosion, discharge of sedimentation by blasting爆炸事故explosion accident备电源stand-by power source备用轨stock rails per kilometer of track, emergency rail stored along the way备用货车reserved cars备用机车locomotive in reserve背负运输车piggyback car背景噪声场强background noise field strength倍程衰减double attenuation倍频衰减frequency doubling attenuation被串通路disturbed channel被盗事故robbery accident, burglary accident被覆层coating被叫/被呼called被叫控制复原方式called subscriber release被叫用户called party被控点controlled point本地电池local battery本地终端local terminal本务机车leading locomotive本务走行公里leading locomotive running kilometers本站作业车local car崩塌collapse, toppling泵电动机pump motor泵轮pump impeller泵支承箱pump supporting box比功率power/weight ratio比面积specific floor area比容（积）specific volume比特bit比特率bit rate比重量weight/power ratio闭环控制closed-loop control闭路式轨道电路close type track circuit闭塞block system闭塞电话interstation train operation telephone, blocking telephone闭塞分区block section闭塞机block instrument闭锁位置locked position of coupler避车洞refuge hole, refuge recess,, refuge niche避车台refuge platform避雷器lightning arrester避雷线lightning conductor避难线refuge siding臂板电锁器联锁interlocking by electric locks with semaphore臂板接触器contacts operated by semaphore臂板信号机semaphore signal臂板转极器pole changer operated by semaphore边沟/侧沟side ditch边坡清筛机ballast shoulder cleaning machine边坡植被防护vegetation on slope边墙side wall边走边卸阀ballast flow control valve编发线marshalling-departure track编码coding编组场综合作业自动化automation of synthetic operation in marshalling yard 编组能力make-up capacity编组调车make-up of trains编组站marshalling station, marshalling yard扁烟筒oblong ejector, Giesl ejector变电所测试车substation testing car变动支出variable expense变更径路route diversion变更设计altered design变极调速pole changing speed control变几何燃气轮机variable-geometry gas turbine变摩擦式减振装置variable friction type snubbing device变扭比/变矩比torque ratio变扭器轴/变矩器轴torque converter shaft变频器frequency converter变频调速variable frequency speed control变坡点point of gradient change, break in grade变位阀changeover valve变压器电势transformer EMF变压器箱transformer box变压调速variable voltage speed control变阻调压rheostatic control便桥temporary bridge便携电台portable radio set标称电压nominal voltage标称功率nominal power标称转速nominal speed标题heading标志sign, marker标志灯marker lamp标志器marker标准大气状况standard atmospheric condition标准分路灵敏度/标准分流感度standard shunting sensitivity 标准贯入试验standard penetration test标准煤standard coal标准长度钢轨standard length rail表示indication表示灯indication lamp表示灯电源power source for indication lamp表示电路indication circuit表示对象indicated object表示杆indication rod表示连接杆connecting rod for indication表示盘indicating panel表示器indicator表示周期indication cycle滨河路堤embankment on river bank冰凌调查ice floe survey, frazil ice survey冰压力ice pressure并行传输parallel transmission并励电动机shunt excited motor并联电容补偿装置compensator with parallel capacitance并联式轨道电路multiply connected track circuit并列式枢纽parallel arrangement type junction terminal并置信号点double signal location拨号dialing拨号脉冲dial impulse拨号盘dial拨号音dialing tone拨号终端dial-up terminal波导线waveguide line波导线传输方式transmission mode with waveguide line波分复用wavelength division multiplex波特baud波纹地板corrugated floor波纹管bellows波形辐板corrugated wheel plate播音连接器public address coupling播音室public address room播音装置public address system补偿电容器compensation capacitor补偿滑轮tension pulley补偿线圈compensating coil补机（牵引区段摘挂机车）banking locomotive不成对运行图train diagram not in pairs不对称脉冲轨道电路asymmetrical impulse track circuit不对称三开道岔unsymmetrical three-way turnout, unsymmetrical three throw turnout 不对称双开道岔unsymmetrical double curve turnout, unequilateral turnout不分开式扣件non-separated rail fastening, direct holding fastening不规则畸变fortuitous distortion不可懂串音unintelligible crosstalk不良地质unfavorable geology不平衡电阻unbalanced resistance不同时到达间隔时间time interval between two opposing trains arriving at station not at the same time不完全燃烧热损失heat loss due to incomplete combustion不限时人工解锁manual non-time release不摘车修in-train repair步行板foot plank步进制电话交换机step-by-step telephone switching system部分预应力混凝土桥partially prestressed concrete bridge部件故障检测inspection of component failure, failure diagnostic材料供应计划material supply plan材料申请计划material requisition plan材料消耗定额material consumption norm, material consumption ratings 材质不良bad material财务管理信息系统financial management information system财务决算审查financial statements review采暖装置heating system参考当量reference equivalent餐车dining car餐车洗池sink餐室dining room残车率rate of bad order cars残废军人票disabled armyman ticket残余废气residual gas残余废气系数coefficient of residual gas仓库warehouse操纵台operating console槽式列车bunker train槽形梁trough girder草测route reconnaissance册页（客）票coupon ticket厕所lavatory, toilet侧摆振动swaying (vibration)侧板side sheet侧壁导坑法side heading method侧窗side window侧灯side lamp侧滚振动rolling (vibration)侧架弹簧承台side frame spring seat侧架立柱side frame column侧架上弦杆side frame top chord侧架上斜弦杆side frame top oblique chord侧架下弦杆side frame bottom chord侧架下斜弦杆side frame bottom oblique chord侧力(maglev) lateral force侧梁side sill侧门side door侧排油阀side oil outlet valve侧墙side wall侧墙包板/包板side sheathing侧倾车体tilting type car body侧向水平联接系lateral bracing侧音side tone侧柱side post侧柱连铁side post connecting rail侧柱内补强inside reinforcement of side post侧撞cornering测段segment of survey测量放样staking out in survey测量精度survey precision, precision of survey测试环线test loop测试台test desk测速speed measurement测速发电机tachogenerator测长distance-to-coupling measurement测重weight sensing测阻rollability measurement叉槽fork pockets叉车fork-lift truck叉簧hook switch插板支护inserting plate support, forepoling插接不良plug-in trouble插孔/插座jack插孔排jack strip插入式混凝土振捣器immersion type vibrator for concrete 插入式继电器plug-in type relay插塞plug茶炉drinking water boiler茶桌tea table查号台information desk岔枕switch tie, turnout tie岔中绝缘insulated joint within a turnout差错恢复error recovery差错检测error detection差错控制error control差错漏检率residual error-rate差分脉码调制differential pulse-code modulation差分调制differential modulation差分移相键控differential phase shift keying, DPSK差转电台radio repeating set拆迁removing拆装式桁架demountable truss柴排firewood raft, mattress, willow fascine柴油打桩机diesel pile driver柴油机diesel engine柴油机爆燃/柴油机工作粗暴engine detonation柴油机净重net weight of diesel engine柴油机起动试验diesel engine starting test柴油机特性diesel engine characteristic柴油机支座engine support柴油机转速表diesel engine tachometer掺混区dilution zone铲运机scoper, scraper, carrying scraper颤振flutter常摩擦式减振装置constant friction type snubbing device 常用局减quick service常用全制动full service braking, full service application 常用制动service braking, service application场间联系电路liaison circuit between yards场库storage yard and warehouse场强覆盖区field strength coverage场强中值median of field strength敞车gondola car, open goods wagon敞顶集装箱open top container超导体superconductor超导体斥力superconducting repulsion force超导悬浮系统superconducting suspension system超范围修理repair beyond the scope of repairing course 超负荷试验cover-load test超前导坑advance heading超前锚杆advance anchor bolt超前支护advance support超群super group超群配线架supergroup distribution frame超声波查漏仪ultrasonic leak detector超速停车装置overspeed trip超挖overbreak超限货物out-of-gauge freight超限货物等级classification of out-of-gauge freight超限货物检查架examining rack for out-of-gauge freight 超长超重列车exceptionally long and heavy train超长货物exceptional length freight潮喷混凝土half wet shotcreting潮汐河流tidal river车场yard车次表示train number indication车挡bumper post车挡表示器buffer stop indicator车底电线管electric wire conduit underneath the car车底数number of allocated passenger trains车电分线盒junction box车顶roof车顶冰箱冷藏车overhead brine tank refrigerator car车顶侧梁roof cant rail车顶端横梁roof end rail车顶横梁roof cross beam车顶弯梁carline车顶纵梁purline车端冰箱冷藏车ice-bunker refrigerator car车端缓冲器end-of-car cushioning device车钩复原装置coupler centering device车钩缓冲停止器device for stopping buffer action车钩缓冲装置coupler and draft gear车钩间隙coupler slack车钩连接线coupling line车钩连结线间长度length over pulling faces of couplers车钩轮廓coupler contour车钩牵引力tractive effort at coupler, drawbar pull车钩三态作用three states of coupler operation车钩托梁coupler carrier车钩中心线高度height of coupler center from top of rail, coupler height 车号number of car车号抄录电视TV for record vehicle number车号灯side number plate lamp车号员无线电通信radio communication for number taker车号自动识别automatic car identification车架frame车辆报废限度car condemning limit车辆标记lettering and marking of car车辆厂修car repair in works车辆冲击car impact车辆冲击试验car impact test车辆存在监测器presence monitor车辆大修car heavy repair车辆定距length between truck centers车辆动力学试验car dynamics test车辆段car depot车辆段检修台位利用率rate of utilization of repair positions in car depot 车辆段修car repair in depot车辆分散供电separate power supply (system) for car车辆辅修car auxiliary repair车辆高度height of car车辆公里car kilometers车辆构造速度design speed of car, construction speed of car车辆横向lateral direction of car车辆互撞car collision车辆换算长度converted car length车辆集中供电centralized power supply (system) for car车辆计算长度calculated length of car车辆技术履历薄technical record book of car车辆加速器car accelerator车辆检修car inspection and maintenance车辆检修率rate of cars under repair车辆检修设备car repair facilities车辆检修停留时间down time for holding cars for repairing车辆检修限度car repair limit车辆检修在修时间down time for car under repair车辆减速器car retarder车辆交直流供电AC-DC power supply for car车辆年修car yearly repair车辆平均长度average length of car车辆强度试验car strength test车辆全长length over pulling faces of couplers车辆全轴距wheelbase of car车辆设计规范specifications for design of cars车辆弯曲振动试验test of vibration caused by carbody bending车辆修理厂car repair works车辆运营car operation车辆运用维修car operation and maintenance车辆运用限度car road service limit车辆长距比/车辆长度与定距比ratio of car body length to length between truck centers 车辆制检car brake examination, car brake inspection车辆制造厂car manufacturing works车辆中修car medium repair车辆轴检car journal and box examination, car journal and box inspection车辆装卸修car repair before loading or after unloading车辆纵向longitudinal direction of car车辆最大高度maximum height of car车辆最大宽度maximum width of car车辆最大允许速度maximum permissible speed of car车列train set车流car flow车流径路car flow routing车流调整adjustment of car flow车流组织organization of car flow车轮wheel车轮不圆wheel out of round车轮厂(car) wheelset repair factory车轮滑行wheel sliding, wheel skid车轮检测器wheel detector车轮静平衡检验car wheel static balance test车轮空转wheel slipping车轮扣环retaining ring (of tire)车轮贴靠flanging车轮直径wheel diameter车门自动控制automatic train door control车票ticket车票有效期ticket availability车上给水装置water supply equipment with roof tank车上水箱roof water tank车体car body车体侧倾装置car body tilting device车体骨架body framing车体及外部装备密封试验test for sealing of body and external equipment 车体宽度width over sides of car body车体内高height inside car body车体内宽width inside car body车体内长length inside car body车体内中心处高度height inside car body from floor to roof center车体长度length over ends of body, length of car body车下电气插座car power receptacle车下给水装置water supply equipment with lower tank车下水箱lower water tank车型mode of car车载地球站vehicle earth station车载钢轨涂油器on-board rail lubricator车站station车站班计划station shift operating plan车站办理车数number of inbound and outbound car handled at station车站等级class of station车站电台station radio set车站分布distribution of stations车站工作组织organization of station operation车站行车工作细则instructions for train operation at station车站技术作业表station technical working diagram车站间隔时间time interval between two adjacent trains at station车站阶段计划station stage operating plan车站控制station master control车站隧道station tunnel车站通过能力carrying capacity of station车站信号signaling at stations车站咽喉station throat车站咽喉通过能力carrying capacity of station throat车站作业计划station operating plan车长电台train conductor’s station车长阀caboose valve, conductor’s valve, guard’s valve车种type of car车轴axle车轴超声探伤ultrasonic inspection for axle车轴齿轮箱axle gear box车轴电磁探伤magnetic particle inspection for axle, magnaflus inspection for axle 车轴发电机axle generator车轴发电机控制箱axle generator control box车轴空心轴驱动quill drive, hollow axle drive车轴模拟试验台axle analogy test machine车轴驱动方式mode of axle drive车轴弯曲bent axle沉管法immersed tunneling method沉井挡墙caisson retaining wall沉井基础open caisson foundation沉井刃脚cutting edge of open caisson沉箱基础pneumatic caisson foundation衬垫pad衬砌lining衬砌变形lining deformation衬砌腐蚀lining corrosion衬砌裂损lining cracking称重试验weighing test成端电缆formed cable成对运行图train diagram in pairs成件包装货物packed freight成组装车car loading by groups承接接头supported joint承力索catenary承力索驰度catenary sag承力索接头线夹catenary splice承力索终端锚固线夹termination fitting for catenary承台bearing platform承载鞍adapter承载系数检定load factor rating乘警train police乘坐舒适度riding comfortableness, ride comfort程控电话交换机stored program controlled telephone switching system驰振galloping持续功率continuous power持续牵引力continuous tractive effort持续速度continuous speed齿轨（传动）机车/齿条（传动）机车rack locomotive冲便阀flush valve冲击荷载impact force of train冲击式钻机impact-type drill machine, percussion type drill machine 冲击系数coefficient of impact冲击因数impact factor冲击座striker, striking casting冲角angle of attack冲刷erosion, scouring冲突collision充电插头charging plug充风/充气charging充风位/充气位charge position充量charge充量系数coefficient of charge充量限制阀filling limiting valve充气避雷器gas filled arrester充气维护型光缆gas maintenance type optical fiber cable充油型光缆jelly filled type optical fiber cable抽验selective acceptance抽样sample抽样试验sampling test抽液管座unloading pipe connection出碴mucking and removing出厂试验predelivery test出发场departure yard出发线departure track出口角blade outlet angle出油阀delivery valve出油阀偶件delivery valve matching parts出油阀座delivery valve seat出站信号机/出发信号机starting signal出中继电路outgoing trunk circuit出中继器outgoing trunk circuit初步设计preliminary design初测preliminary survey初期支护primary support除草机weed cutting machine, weed cutter除砂机sand removing machine除雪车snow plow, snow plough除雪机snow removing machine, snow remover厨房kitchen厨房车kitchen car杵环杆bar with ball and eye, ball-socket bar杵座鞍子socket-type saddle储备功率reserve power储藏室storage room储风罐air reservoir储酸室acid store room触电保安器electric shock protector穿销防爬器wedged rail anchor传导干扰conducted interference传导模guided modes传动齿轮transmission gear传动系统driving system传动轴transmission shaft传感器sensor, transducer传输继电器transmitting relay, transmission relay传输结束信号end-of-transmission signal传输线transmission line传输性能transmission performance传送同步方式transmission synchronized mode传真发送机facsimile transmitter传真机facsimile apparatus, Fax传真接收机facsimile receiver传真收发机facsimile transceiver船只或排筏的冲撞力collision force of ship or raft喘振surge串行传输serial transmission串励电动机series excited motor串联电容补偿装置compensator with series capacitance 串联式轨道电路serially connected track circuit串音crosstalk串音测试器crosstalk meter串音防卫度signal to crosstalk ratio串音抑制滤波器crosstalk suppression filter窗间板pier sheathing窗卷帘window blind, window shade窗口window窗框window sash窗帘window curtain窗锁window sash lock窗台window sill, window rail床头灯berth lamp炊事室cooking room垂度sag垂直板/垂直反射板diaphragm plate, deflecting plate垂直冲击vertical impact垂直动荷载vertical dynamic load垂直荷载vertical load垂直振动vertical vibration磁（悬）浮maglev, magnetic levitation磁（悬）浮车辆maglev vehicle磁场削弱接触器field weakening contactor磁场削弱率field weakening磁场削弱系数coefficient of field weakening磁浮铁路magnetic levitation railway, maglev磁感应magnetic induction磁轨制动electromagnetic rail brake磁路（系统）magnetic circuit磁轮magnet wheel磁石电话机magneto telephone set磁石电话交换机magneto telephone switch board磁石发电机magneto次应力secondary stress从板follower从动齿轮driven gear从动轮对/他动轮对driven wheel set从轮对trailing wheel set从轮转向架trailing truck从属信号机dependent signal从站slave station粗粒土填料coarse-grained soil filler, coarse-grained soil fill 窜机油lubricating oil carry-over窜气blow-by淬火轨head hardened rail, quenched rail淬火尖轨surface-hardened switch rail, quenched switch rail 存车线storage siding存储转发store and forward错乘taking wrong train错溜misroute错误办理wrong handling错误关闭信号false stopping of a signal错误解锁false release错误开放信号wrong clearing of a signal错误锁闭false locking错误显示wrong indication错牙接头rail ends unevenness in line or surface打道钉机spike driver打磨钢轨rail grinding打桩机pile driver大地电阻率earth resistivity大功率转辙机heavy duty switch machine大轨缝excessive joint gap, wide joint gap大横梁cross bearer大揭盖清筛机ballast cleaning machine with removed track panels大陆桥transcontinental railway, intercontinental railway, land-railway大气压式采暖装置atmospheric pressure steam heating equipment大气压式暖汽调整器vapor regulator大桥major bridge大事故serious accident大型矿车large scale ore car大型临时工程large-scale temporary project大型全断面清筛机large ballast undercutting cleaners, on-track full section undercutting cleaners大型线路机械heavy permanent way machine, large permanent way machine大修计划plan of capital repair大烟管flue (tube)大腰带waist rail大闸automatic brake valve大站电气集中联锁relay interlocking for large station大宗货物mass freight代用票substituting ticket带柄道岔表示器switch indicator with level带动道岔switch with follow up movement带回流线的直接供电方式direct feeding system with return wire带裙鱼尾板fish plate with apron带式输送机belt conveyer待避所refuge place待修机车locomotive waiting for repair单臂受电弓single arm pantograph单边带通信single side band communication单边供电one way feeding单边型直线感应电动机single sided linear induction motor单侧（踏面）制动single shoe brake单侧导坑法single side heading method单侧减速齿轮驱动single reduction gear drive单车试验single car test单车试验器single car testing device单电动机驱动monomotor drive单斗挖掘机power shovel单独操纵继电式电气集中联锁individual level type all-relay interlocking单独操纵作业manual operation单独制动阀independent brake valve单断single break单缸功率power per cylinder单工simplex operation单工传输simplex transmission单工无线电通信simplex radio communication单管逆变器individual inverter单管荧光灯single tube fluorescent lamp单轨条式轨道电路single rail track circuit单轨铁路monorail, monorail railway单轨小车hand cart单呼individual calling单回路供电single circuit power supply单机运行light locomotive running单机走行公里light locomotive running kilometers单肩回交路single-arm routing单节机械冷藏车mechanical refrigerator car单局制single-office system单开道岔simple turnout, lateral turnout单梁式架桥机single beam girder-erecting machine单流single current单流液力机械传动hydromechanical drive with inner ramification单面托盘single-deck pallet单模光纤single-mode optical fiber单频感应器single frequency inductor单曲线simple curve单式不对称道岔unsymmetrical double curve turnout, unequilateral turnout单式对称道岔symmetrical double curve turnout, equilateral turnout单式交分道岔single slip switches单式同侧道岔unsymmetrical double curve turnout in the same direction单双工兼容无线电通信compatible simplex-duplex radio communication单筒壁灯single cylindrical shade wall lamp单位工程unit project单位活塞面积功率piston unit area power单位体积功率specific volume power单位阻力unit resistance, specific resistance单线臂板信号机single wire semaphore signal单线继电半自动闭塞single track all-relay semi-automatic block system单线桥single track bridge单线隧道single track tunnel单线铁路single track railway单线运行图train diagram for single track单线制single wire system单相V/V接线牵引变压器traction transformer of singlephase V/V connection单相低频交流制single-phase low frequency AC system单相电度表single-phase wat-hour meter单相工频交流电动车组single-phase industrial frequency AC motor train unit单相工频交流电力机车single-phase industrial frequency AC electric locomotive单相工频交流电力牵引制single-phase industrial frequency AC electric traction system单相工频交流制single-phase industrial frequency AC system单相交流电力机车single-phase AC electric locomotive单相交流牵引电动机single-phase AC traction motor单相接线牵引变压器traction transformer of singlephase connection 单相桥式整流器single-phase bridge rectifier单向传输unidirectional transmission单向横列式编组站unidirectional transversal type marshalling station 单向混合式编组站unidirectional combined type marshalling station 单向通信one-way communication单向自动闭塞single-directional running automatic block单向纵列式编组站unidirectional longitudinal type marshalling station 单项预算individual budget单循环液力传动single-circuit hydraulic transmission单元列车unit train单元制动brake unit单胀式蒸汽机车single expansion steam locomotive单置信号点single signal location单轴燃气轮机single-shaft gas turbine单轴转向架single-axle truck单转子滑片式空压机single rotary compressor弹簧补偿器spring tensioner弹簧道钉elastic rail spike弹簧垫圈spring washer弹簧动扰度dynamic spring deflection弹簧防爬器spring rail anchor弹簧刚度spring stiffness弹簧静扰度static spring deflection弹簧摩擦式缓冲器spring friction draft gear弹簧柔度spring flexibility弹簧式减振器spring damper弹簧托板spring plank弹簧托梁spring plank carrier弹簧悬挂装置spring suspension弹力继电器spring-type relay弹性车轮elastic wheel弹性齿轮驱动resilient gear drive弹性垫板rubber tie plate弹性定位轮对elastically positioned wheelset弹性挤开gage elastically widened, elastic squeeze-out弹性简单悬挂stitched tramway type suspension equipment弹性抗力elastic resistance弹性扣件elastic rail fastening弹性链形悬挂stitched catenary equipment弹性旁承elastic side bearing弹性止挡elastic bolster guide当量跨距equivalent span length挡车器stop buffer挡风墙wind-break wall挡石墙stone cut off wall, stone falling wall, buttress wall for intercepting falling rocks 挡土墙retaining wall挡烟板smoke deflector刀把梁lowered draft sill导程lead导风轮inducer导管调整器pipe compensator导管装置pipe installation导轨与悬浮系统相互作用guideway suspension interaction导坑heading导框式转向架pedestal truck导流堤diversion dike导流建筑物regulating structure导轮guide wheel导轮对leading truck wheel set导轮转向架leading truck导纳电桥admittance bridge导频pilot frequency导频放大器pilot amplifier导频无人增音机pilot unattended repeater导曲线lead curve导曲线半径radius of lead curve导曲线支距offset of lead curve导热系数coefficient of thermal conductivity导线安装曲线wire installation curve导线测量traversing, traverse survey导线导轮wire carrier导线反正扣wire-adjusting screw导线立轮vertical wheel导线平轮horizontal wheel导线平轮组horizontal wheel assembly导线调整器wire compensator导线装置wire installation导向安全failure to the safe side导向力guidance force导向系统guidance system导向线leading line, alignment guiding line导音频信号pilot audio frequency signal捣镐packer, tamping pick, beater捣固道床ballast tamping。
威能极变频器
一个风力发电机的电系统 The electrical system of a wind turbine
具有最佳电网质量的优质风力发电机 High-quality wind turbines with optimal grid quality
Dynavert XL@ 变频器 和开关设备 各种优点
提供恒定的有功功率： 通过操作管理可以实现恒定输出功率或 恒定扭矩的恒定运作。在变频器控制系 统中储存了一个有功功率与转速关系的 表格。作为选项可以给出一个外部的扭 矩信号。 闪变效应小：
变频器 Inverters
采用变速传动系统进行发电
Current generation for the variable speed drive train
采用变速传动系统进行发电 Electric power generation for the variable-speed drive system
传动系统效率高： 与转速恒定的系统相比，此系统具有显 著改善了的局部负荷效率。
Low flicker values: The properties of the Dynavert XL® system prevent flicker effects almost completely. Very good efficiency of the electrical system: Compared with systems with full-load inverters, this system is superior in station efficiency, as the output of the inverter is only around 1/3 of the system output.
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On Power Quality of Variable-SpeedConstant-Frequency Aircraft ElectricPower SystemsAhmad Eid,Student Member,IEEE,Hassan El-Kishky,Senior Member,IEEE,Mazen Abdel-Salam,Fellow,IEEE,and Mohamed T.El-Mohandes,Member,IEEEAbstract—In this paper,a comprehensive model of the variable-speed constant-frequency aircraft electric power system is devel-oped to study the performance characteristics of the system and, in particular,the system power quality over a frequency range of operation of400Hz to800Hz.A fully controlled active power filter is designed to regulate the load terminal voltage,eliminate harmonics,correct supply power factor,and minimize the effect of unbalanced loads.The control algorithm for the active powerfilter (APF)is based on the perfect harmonic cancellation method which provides a three-phase reference supply current in phase with its positive-sequence fundamental voltage.The proposed APF is inte-grated into the model of a90-kV A advanced aircraft electric power system under VSCF operation.The performance characteristics of the system are studied with the frequency of the generator’s output voltage varied from400Hz to800Hz under different loading con-ditions.Several case studies are presented including dc loads as well as passive and dynamic ac loads.The power quality charac-teristics of the studied aircraft electric power system with the pro-posed activefilter are shown to be in compliance with the most re-cent military aircraft electrical standards MIL-STD-704F as well as with the IEEE Std.519.Index Terms—Aircraft power system,active powerfilter(APF), total harmonic distortion(THD),variable-speed constant-fre-quency(VSCF).I.I NTRODUCTIONT HE architecture of a conventional civil aircraft consists of a combination of systems:mechanical,pneumatic, hydraulic,and electrical systems.These systems have several drawbacks,such as low efficiency and difficulty in detecting leaks in a pneumatic system;the use of gearboxes in a mechan-ical system;heavy,inflexible piping;and the potential leakage of dangerous and corrosivefluids for the hydraulic system[1]. The concept of the“all-electric aircraft”and the“more electric aircraft”(MEA)have been introduced to overcome some of the drawbacks found in conventional architectures and bringManuscript received November20,2008.First published October02,2009; current version published December23,2009.Paper no.TPWRD-00873-2008.A.Eid is with the Electrical Engineering Department,South Valley Univer-sity,Aswan,Egypt.He is also with the University of Texas at Tyler,Tyler,TX 75799USA(e-mail:ahmadeid@).H.El-Kishky is with the Electrical Engineering Department,The University of Texas at Tyler,Tyler,Texas75799USA(e-mail:helkishky@). M.Abdel-Salam is with the Electrical Engineering Department,Assiut Uni-versity,Assiut71518,Egypt(mazen2000m@).T.El-Mohandes is with the Electrical Engineering Department,South Valley University,Aswan81542,Egypt(tharwatm@).Digital Object Identifier10.1109/TPWRD.2009.2031672more attractive advantages,such as improved fuel consump-tion,and lower maintenance and operation costs[1]–[3].The electrical power does not require a heavy infrastructure and is veryflexible.However,it still suffers some drawbacks,such as low-power density compared to hydraulic power and may result in a higher risk offire in case of a short circuit.The constant-speed drive(CSD)generating system found on-board many aircrafts is comprised of a three-stage regulated syn-chronous generator,the output frequency of which is maintained constant by means of a hydro-mechanical CSD connecting it to the engine via a gearbox.A reduction in the weight of the system is brought about by a combination of the drive and the generator integrated into a single unit,thereby providing the integrated drive generator(IDG)[3],[4].However,continuing develop-ments in power electronics and microprocessor technology have led to the dc-link variable-speed constant-frequency(VSCF) generating system[5],[6],becoming a viable alternative to the CSD and IDG systems.The VSCF electrical system is more flexible compared to the CSD/IDG systems since its compo-nents can be distributed throughout the aircraft,in contrast to the CSD/IDG mechanical system in which they must inevitably be located close to the engine.In this paper,a complete model for the VSCF advanced aircraft electric power system(EPS)is developed.A fully con-trolled APF is designed to regulate the load terminal voltage, eliminate harmonics,correct supply power factor,and to min-imize the effect of unbalanced loads.A three-phase-based current-controlled voltage-source inverter is used as an APF. The control algorithm for the APF is based on the perfect harmonic cancellation method which provides a three-phase reference supply current in phase with its positive-sequence fundamental voltage.The proposed APF is integrated into the model of a90-kV A advanced aircraft electric power system under VSCF operation.The performance characteristics of the system are studied with the frequency of the generator’s output voltage varied from400Hz to800Hz under different loading conditions.This paper is organized as follows:the VSCF aircraft EPS model is described in Section II.The simulation results and characteristics of the system without APF are presented in Section III.In Section IV,a proposed shunt APF to improve power quality of the VSCF aircraft EPS is presented,while Section V presents the results and characteristics of the VSCF aircraft power system integrated with the shunt APF at the generator terminals,and conclusions are drawn in Section VI.0885-8977/$26.00©2009IEEEFig.1.Modeled VSCF aircraft electric power system with the APF,inverter passivefilter,main loads,and controllers.II.S TRUCTURE AND M ODELING OF THE VSCFA IRCRAFT E LECTRIC P OWER S YSTEMA.Generating SystemThe Boeing767aircraft electric power system consists of two independent channels,according to the number of starters/gen-erators in the aircraft and an auxiliary/emergency power unit (APU)that contains an additional auxiliary starter/generator to provide power engines starting as well as for emergency backup. The generating system is comprised of starter/generators,power control units,and a generator and system control unit.A single channel of the aircraft electric system is studied here and shown schematically in Fig.1.Although the rated frequency of the aircraft power system is 400Hz,in a VSCF system,the engine speed changes at approx-imately a1:2ratio,resulting in the aircraft synchronous gen-erator frequency changing in the range of400Hz to800Hz [7]–[9].During starting mode,the constant frequency system provides power through the interface power converter to the electric machine which acts as a starter to the aircraft engine.In the generating mode,the variable-speed engine in the aircraft acts as the prime mover for thefield-controlled synchronous generator,resulting in variable frequency output power at the generator’s terminals.This power is then delivered via the in-terface converter(dc link)to the constant frequency(400-Hz) aircraft electric power distribution system.The modeled aircraft power system is equivalent to the Boeing767electric power system with a generator output of 90-kV A per channel.In this model,different load combinations are studied,including passive and dynamic ac loads as well as various dc loads on the aircraft system.Nonlinear loads, including constant power,constant current,as well as constant voltage loads are also considered.Several case studies are presented,including nonlinear as well as passive and dynamic ac loads.The power-quality characteristics of the studied aircraft electric power system with the proposed activefilter are shown to be in compliance with the most recent military aircraft electrical standards MIL-STD-704F[7]as well as with the IEEE-Std.519[10].Due to power conversion units used to obtain dc voltage and regulated200-V AC(line voltage) at the ac load terminals,harmonics are generated in supply (generator)voltage and current waveforms.To meet the mili-tary aircraft electrical standards MIL-STD-704F as well as the IEEE-Std.519,a fully controlled shunt APF is designed and integrated into the aircraft electric power system.The modeled aircraft power system parameters are listed in Table V while the governing equations of the aircraft generating system are presented in the Appendix.B.Rectifier UnitIn order to eliminate the low-frequency output current har-monics of the synchronous generator,a transformer rectifier unit (TRU)with a passive12-pulse power converter[2],[11],[12]is used in this study.The TRU,connected to the three-phase gen-erator as shown in Fig.1,provides inherent high power factor and low harmonic distortion.The power factor can be as high as 0.99with a total harmonic distortion(THD)of about13%[2], [3].Power diodes in the TRU are normally robust and with no switching required,it means significant reduction in losses and, hence,improved efficiency as well as significant improvement in power quality of the system with lower harmonic contents and voltage transients.The Y/Y/D transformer in the VSCF aircraft power system provides the necessary phase shift of30for the 12-pulse operation feeding into the main270-VDC bus(Fig.1).A dc capacitor is connected at the output of the power con-verter to smooth out the dc voltage.As the speed of the aircraft engine varies in the1:2range,the output voltage of the syn-chronous generator varies in frequency as well as in magnitude.EID et al.:POWER QUALITY OF VSCF AIRCRAFT ELECTRIC POWER SYSTEMS57Fig.2.Various controlled dc loads connected to the270-VDC bus in the VSCF aircraft power system.In turn,the270-V dc bus is regulated by controlling thefield cur-rent of the synchronous generator by using a feedback propor-tional-integral(PI)controller to meet the aircraft electrical stan-dards[7].The100-kV A three-winding transformer(Fig.1)has a4%leakage inductance,a magnetizing current of1%,andanratio of3with a full-load voltage regulation of3.2%.Mod-eling and characterization of the VSCF aircraft power systemwas accomplished with the PSIM6.0software package[15]withpostprocessing performed in MATLAB.C.DC LoadsIn the proposed VSCF aircraft electric power system model,three different types of dc loads totaling35.6kW are connectedto the regulated270-VDC bus through various dc–dc converters.All controlled dc loads employ the simplest type of dc-dc con-verter configurations in which only one switch is needed and,hence,significantly minimizing switching losses.These loadsare classified as constant power(CP)loads,constant current(CC)loads,and constant voltage(CV)loads,as shown in Fig.2.The dc loads are distributed throughout the aircraft and usedfor various purposes,including heating services,actuation,sub-system controllers,and avionic systems[3].The constant power load is connected to the main dc busthrough a dc–dc buck converter where the load power is keptconstant at10kW via controlling the sensing inductor currentusing a PI controller.The reference current is calculated by di-viding the input reference power by the sensor output voltage.The PI controller modulates the error signal which is then com-pared to a sawtooth signal to generate a gate signal for theswitch.Similarly,the CC load is obtained by using a controlleddc–dc buck converter.The load current is regulated and set at100A by using a PI controller with a resulting load voltage of200V and,hence,20-kW load power.On the other hand,the constant voltage load is regulated tohave an output voltage value of28VDC which is used for thebattery system and other constant voltage dc loads in the air-craft system.A forward power converter is used to reduce the270-V DC voltage level to a suitable controlled voltage by usinga high-frequency transformer.At steady state,the load will drawapproximately200A with a load power of approximately5.6kW.D.Power InverterThe rms output voltage of a sinusoidal PWM inverter is givenin terms of its input dcvoltage and the modulationindex[13]as(1)For a rated rms output voltage per phase of115V and a mod-ulation index of1,the lowest required dcvoltage is325V.Therefore,a12-pulse PWM inverter equipped with an outputpassivefilter is used in the system(Fig.1).Since the turns ratioofthe transformeris times that of the Y-connected trans-former and the pulse train of one converter is shifted by30withrespect to the other,the combined output voltage would have a12-pulse waveform,with a harmonic order givenby(2)The THD of the voltage is givenas(3)where is the characteristic harmonicorder,is a constant(),is the converter pulsenumber,is the harmonicvoltage,and is the fundamental voltage.To provide115V/200V rms,400Hz at the main ac bus,and to further reduce the amount of harmonics injected intothe supply,two six-pulse inverters are used and fed from the270-VDC main bus.The inverters are directly connected to theprimary windings of two separate three-phase transformers.Inturn,the Y/Y and Y/D transformers are connected to the mainac bus to provide the30phase shift needed for a true12-pulseinverter.The12-pulse inverter is controlled by using a PI con-troller to provide a phase voltage of115V,400Hz at the mainac load bus.The voltage error signal is processed by the PI con-troller to provide the required modulationing thegenerated modulationindex,the appropriate gate signals aregenerated and fed to the twin six-pulse inverters.E.AC LoadsBoth passive and dynamic ac loads are considered in the mod-eled VSCF aircraft electric power system.Passive loads are sim-ulated by using lumped circuit elements of series RL with a min-imum load power factor of0.85lagging as recommended byaircraft electrical standards[7].The ac loads are labeled A,B,and C and are shown schematically in Fig.1.More details arepresented in Table I.Furthermore,the dynamic loads are simu-lated with three induction motorslabeled,,and,re-spectively(Fig.1).The selected motors are of ratings11.2kW,7.5kW,and5.0kW,respectively(Table I).The motors whichcommonly exist[14]on an aircraft for electro-hydro mechan-ical actuation are connected to the115/200-V,400-Hz main ac58IEEE TRANSACTIONS ON POWER DELIVERY ,VOL.25,NO.1,JANUARY 2010TABLE IAC L OADS PARAMETERSTABLE IIL OAD C ASE -S TUDIES OF THE M ODELED VSCF A IRCRAFTEPS.bus.The motors are loaded with constant load torque and fed from the main ac load bus along with the passive ac loads.III.P ERFORMANCE C HARACTERISTICS OF THEVSCF A IRCRAFT EPS W ITHOUT APFThe proposed model of the VSCF aircraft electric power system shown in Fig.1is developed and characterized by using the PSIM6software package with postprocessing completed in MATLAB.In the model,the synchronous generator speed is controlled by using a speed governor to provide an output with a frequency range of 400to 800Hz with the systems nominal frequency set at 400Hz.Different loading scenarios of the aircraft power system are presented in Table II with three case studies,including combinations of both ac and dc loads.The first case study dealing with various dc loads in the system,examines the effects of the 12-pulse passive rectifier on the system performance.With 35kV A,the combined dc loads represent approximately 40%of the total power capacity per channel on the aircraft system.All passive (A,B,C)anddynamic(,,)ac loads are combined and considered in case study 2,which represents slightly more than 60%of the total power capacity per channel on the aircraft system.The last case study investigates the VSCF aircraft power system characteristics under full-load condition with all ac and dc loads connected to the system.In each case study,the current and voltage characteristics are generated and the THD values are calculated and compared to the established aircraft electrical standards.Moreover,the rms value of the generator voltage()and current()as well as the ac load bus voltage()and current()are recorded.In case study 1,considering dc loads only with the dc power obtained by using a 12-pulse passive rectifier,the expected characteristic harmonics are given in (2).All power-quality characteristics of the VSCF aircraft system are generated over a 400-to 800-Hz frequency range of operation.The simulation results of the first case-study (cs1)show in-teresting behavior of the harmonic contents in the generator voltage and current waveforms over the frequency range of oper-ation as shown in Fig.3.The THD value of the generatorvoltageFig.3.Calculated THD values for Vg and Ig without APF.can be more than 11%at 800-Hz operation,while the maximum THD value for the generator current is slightly less than 10%and occurs at 400Hz.The THD values of the generator voltage increase with increasing frequency while the THD values for the generator current decrease with increasing the frequency of operation (Fig.3),which may be attributed to the inductive na-ture of the system harmonic impedance.Due to the assumed balanced conditions of the load and source,the THD values re-main consistent for all phases.In case study 2(cs2),only ac loads are connected to the mod-eled VSCF aircraft electric power system through a 12-pulse sinusoidal PWM inverter (Fig.1),the calculated THD values are comparable to those obtained in cs1while maintaining vir-tually the same trend of variation against frequency.With the full load applied in cs3,the THD in the generator voltage stays virtually leveled at approximately 12%.Further investigation of Fig.3shows that the THD values of the generatorcurrent are significantly higher at lower loads (cs1)compared to those ob-tained at higher loads (cs2and cs3).This may be attributed to a lower fundamental component ofthe generatorcurrentat lighter loads which makes the THD value considerably higher than those obtained at higher loads.At higher frequencies,the THD of the generator current falls to within the standard limit of 5%[7],[10],Fig.3.The wave-forms of the generatorvoltageandcurrent are shown in Fig.4for cs3with all combined ac and dc loads connected to the modeled VSCF aircraft electric power system at different fre-quencies.The calculated THD values of the generator current remain low and within the established standard limits over the entire frequency range of operation.However,the THD values of the generator voltage are significantly higher and remain vir-tually constant at 12%over the frequency range,which may be attributed to the inductive nature of the system harmonic impedance (Fig.3).Moreover,Fig.3shows the THD of the cur-rent and voltage at the generator terminals compared to the max-imum value of 5%as required by IEEE Std-519and MIL-STD-704F.EID et al.:POWER QUALITY OF VSCF AIRCRAFT ELECTRIC POWER SYSTEMS59Fig.4.Case study No.3generator voltage (Vg )and current (Ig )waveforms at different frequencyoperation.Fig.5.Plot of the currents and voltages at the main dc and ac buses.The waveforms showing transients in the main dc-bus current and voltage as well as in the main ac bus are presented in Fig.5with the timed load switching.IV .P ROPOSED APF M ODEL AND C ONTROL S TRATEGY A.Mathematical Modeling of APFThe APF,in general,is comprised of a power circuit,such as a voltage-source inverter (VSI),a smoothinginductors with a seriesresistance ,and a dccapacitor as shown in Fig.6.The capacitor connected to the dc bus of the VSI serves as an energy-storage ing simple network analysis,the performance of the APF model can be described with the governing differential (4)at the ac side[16](4)whereand are the series resistance and inductance per phase of theAPF,is the APF phase current,while is the PWM phase voltages at the ac sideand takes a,b,c.The corresponding equation on the dc side can be given by[16](5)Fig.6.APF configuration and connection.where is the energy-storage capacitance connected to the dcside of the APFandis the available input dc voltage.The three-phase APF voltages can be expressed in terms of the dc voltage and the switching functions (SA,SB,and SC)according to the control circuit asgiven(6)B.Control Method of the Proposed APFAlthough the instantaneous reactive power theory (-theory)is widely used in the APF control circuitry to calculate the desired compensation current [17]–[22],it is very sensitive to distortion and imbalance that may occur in the voltage at the point of common coupling (PCC).On the other hand,the unity power factor control method [23],[24]does not work well in the presence of zero-sequence voltage components.Similar to the-control strategy,the -control method [25],[26]is sensitive to distortion and to imbalance.For full compliance with the respective harmonics standards,imbalance elimina-tion,and reactive power compensation,the perfect harmonic cancellation (PHC)method [22],[23]is the control strategy of choice that is capable of corrective action under all conditions.This,in turn,is achieved through a two-stage procedure.First,the reference filter currents(,,and )are obtained and in the second stage,a PWM hysteresis band current control is used to generate the required gate signals(-)which are then fed to the inverter switches.The PHC control method is adopted here to generate the re-quired compensation currents for the shunt active power filter.The governing equations of the PHC control method can be de-rived [22]–[27].Any set of voltages(,,)and currents(,,)can be transformed intothe --0systemwhere is the transformation matrix using the power invariantas(7)60IEEE TRANSACTIONS ON POWER DELIVERY,VOL.25,NO.1,JANUARY2010 The function of the APF,controlled with the PHC method,isto compensate for all of the harmonic currents,provide the fun-damental reactive power demanded by the load,and eliminateimbalance if it exists.To achieve these objectives altogether,the source current must be in phase with the fundamental posi-tive-sequence component of the voltage at PCC[23].Therefore,the reference source current can be given in theform(8)where is the PCC voltage positive-sequence component.The power delivered by thesource willbe(9)Theconstant can be determined by using the condition thatthe source power is equal to the average power(activepower)demanded by the load,thus(10)The reference source current will then be given by[27](11)After convertingthe --0components to the a-b-c phasequantities,the APF reference currents are generated as[27](12)Complete details of the PHC control method steps as calcu-lated in the simulation program are shown in Fig.7.A hysteresisband PWM current control scheme is applied in this study tocontrol the inverter so that its output current follows the refer-ence current waveform[27],[28].In this method,the switches inan inverter are asynchronously controlled and the actual currentis ramped up and down to follow the reference current.Whenthe actual current exceeds the upper limit or drops below thelower hysteresis limit,the associated switching pattern of theswitch will force the current to get back within the hysteresisband limit.Hence,the current ramp can be altered by the widthof the hysteresis band.Decreasing the hysteresis band results inthefilter current by following exactly thefilter reference cur-rent;however,it increases switching losses.V.P ERFORMANCE C HARACTERISTICS OF THEVSCF A IRCRAFT EPS W ITH APFThe VSCF aircraft electric power system model with theproposed fully controlled active powerfilter is developedand studied under steady-state conditions.A three-phasecurrent-controlled VSI inverter is used as an APF.The con-trol algorithm for the APF is based on the perfect harmoniccancellation method which provides a three-phase referencesupply current in phase with its positive-sequence fundamentalvoltage.The PHC control method will maintain the PF of thegenerator at or near unity.At the115-V/200-V main ac loadbus,a sinusoidal PWM12-pulse inverter transforms thedcFig.7.APF control circuit configuration using the PHC method.TABLE IIID ESIGN P ARAMETERS OF THE P ROPOSEDAPFvoltage into ac to feed all ac loads connected to the aircraftEPS.The inverter outputfilter(see Fig.1)mitigates the generatedharmonics of the PWM inversion,and the inductive nature of theac loads helps mitigate current harmonics along with the passivefilter.The inverter outputfilter consists of a series inductor alongwith a shunt capacitor each having a small series resistance(Fig.1).The design parameters of the inverter outputfilter are givenin Table III with the series inductorvalue selected at0.1mHwith a seriesresistance of10-m and the shunt connectedcapacitor has a set value of0.2mF and aresistance of20m.A complete list of the APF design parameters is presentedin Table III.The proposed APF is integrated into the model of a90-kV Aadvanced aircraft electric power system under variable-speedconstant-frequency operation.The performance characteristicsof the VSCF aircraft system power quality are studied with thefrequency of the generator’s output voltage varied from400to800Hz under different loading conditions.Several case studiesare presented including dc loads as well as static and dynamicac loads.The THD values of the generator voltage and current are cal-culated for the same case studies(cs1-cs3)with different loadingscenarios with the APF installed at the generator terminals andEID et al.:POWER QUALITY OF VSCF AIRCRAFT ELECTRIC POWER SYSTEMS61Fig.8.Generator voltage and current THD for the three studied cases when installing the APF at the generator terminals.TABLE IVR EDUCTION IN THD V ALUES OF THE G ENERATORV OLTAGE AND C URRENT W ITHAPFplotted in paring Figs.3and 8,one can see a sig-nificant drop in harmonic contents in the generator voltage and current waveforms over the frequency range of operation.The voltage-stiff nonlinear load of the diode rectifier unit with a large capacitive filter at the dc link feeding the VSI inverters results in nonsinusoidal currents and significant distortions of the ac terminal voltage.The voltage-source loads connected to the main ac bus draw discontinuous and nonsinusoidal currents with high THD and contribute to high THD,low-power factor,and distortion of ac voltage.A measure of the harmonic compensation effectiveness of the proposed APF is presented in Table IV.The percentage drop of the THD values of the generator voltage and current after installing the APF over the frequency range of operation are presented.The recorded drop in the generator current’s THD ranges from slightly less than 18%to 87%,while a range of drop of 72%to 92%was achieved in the voltage THD.It is impor-tant to point to the fact that the inductive nature of the system harmonic impedance of the modeled VSCF aircraft EPS con-siderably contributed to lowering the current harmonic contents and particularly at higher frequencies.Generally,the APF’s ef-fective harmonic compensation and the overall improvement in power quality of the VSCF aircraft EPS may be attributed to the effective PHC control scheme of the proposed fast-switching,real-time APF.In case study 3(full load),the loadcurrent ,the generatorcurrent ,and the APF phasecurrent (see Fig.6)are shown in Fig.9.The generator waveforms of phase voltage andcurrentFig.9.Load currenti ,the generator current i ,and the APF current i forphasea.Fig.10.Generator voltage and current for phase a,b and c at full load.are shown in Fig.10.With the PHC control method of the con-nected active filter,the generator’s PF is maintained near unity which can be seen from the virtually zero phase shift between the generator voltage and current in Fig.10.The change of the generator’s PF with and without the shunt APF over the entire frequency range of operation from 400to 800Hz is presented in Fig.11.The effect of the APF in correcting the generator’s PF is obvious.The transient voltage characteristics of the modeled VSCF aircraft EPS are presented in Figs.12and 13.Passive ac loads are switched to the aircraft system after 100ms (allowing enough time for the generator voltage to reach steady state),followed by dynamic ac loads which are switched to the system after 250ms,and then the nonlinear dc loads are switched on after 350ms.Fig.12shows the generator phase voltage profile at 400,600,and 600Hz.Further investigation of Fig.12shows that the generator voltage transients are more significant toward the high end of the frequency range of operation;however,the transient magnitude and time duration are still within the strict requirements of the aircraft military standards.Fig.13shows the voltage transients at the main 270-VDC bus in response。