电磁干扰开关电源中英文对照外文翻译文献
开关电源发展轨迹中英文翻译资料
Switching Power Supply Development TrackDevelopment of switching power supply (Review Xuanlan) switching power supply (hereinafter referred to switch power) to replace the linear regulator power transistors (hereinafter referred to the linear power) has 30 years of history, is the earliest the series switching power supply, its main Linear power supply topologies and similar, but the power transistor to switch to a later state PWM (PWM) control techniques have been developed for the control switch converters, by PWM switching power supply, it is characterized by using 20 kHz frequency or pulse PWM a PWM switching power supply efficiency is about 65 to 70 percent, while the efficiency of linear power only 30 of a 40 per cent. In the event of the world's energy crisis, caused people to a wide range of customs. Linear power supply works in the frequency, the frequency used for the 20 kHZ the PWM switching power supply alternatives, could significantly conserve energy and power technology in the history of the development called 20 kHZ revolution. With ULSI chip size decreases, the size and power is much greater than the microprocessor; spacecraft, submarines, military power and switch the batteries used portable electronic devices (such as mobile computers, mobile phones, etc.) need more small , Lightweight power. Hence the switch to power a small light requirements, including magnetic components and capacitors the size of small weight. In addition switching power supply requirements to higher efficiency, better performance, reliability, and so on. China's switching power supply from China's history of the development process of switching power supply can understand the international development of a switching power supply side, although generally speaking, China's level of technological development with the international advanced level in an average of 5 to 10 gap. 1970s, I join in black and white TV sets, small and medium-sized computer in the beginning of 5 V ,20-200A, 20kHZ AC-DC switching power supply. 1980s into mass production and extensive application stage and Development of 0.5 ~ 5 MHz quasi-resonant soft-switching power supply. In the 1980s, China's communications (such as the switch-Note) in the AC-DC power supply and DC-DC switching power supply in the area of application is still relatively low proportion of six. The end of the 1980s large-scale upgrading of China's communication power, the traditional ferromagnetic regulator - Rectifier and SCR (Thyristor, formerly known as SCR components) Phased power supply for high-power (48 V, 6kw) AC-DC Switching Power Supply (often referred to as communications systems switch Rectifier SMR) by substituting, and started in the office automation equipment in the applications. Industrial applications, in the boiler flame control, protection, laser, color TV, the filament-emission current regulation, ion-injection machine, Luwu Deng control systems in both applications. The 1990s, China's also developed a number of new non-clearance for power, the typical examples are as follows: 1. Satellite switching power supply. The East is Red on the 3rd communication satellite, Fengyun 1, 2 meteorological satellite applications are the switching power supply. Features: Multi-output, non-maintenance, long-term requirements do not change the performance, set up redundant modules, high reliability, EMC meet the space environment conditions, high efficiency, small light. 2 long-range rocket control system for DC-DC switching power supply to launch the process of highly reliable. 3 1000kW traction converter 4500 V/1200A GTO gated 250 W switching power supply. 4 40kW solid pulse laser soft switching power supply. 10 kw with four more resonant full bridge ZVS converters parallel. 5. Welder double-IGBT forward to the voltage conversion for a pulse modulation (ZVT-PWM) soft switching power supply. Output 20 kW, 500A, switching frequency of 40 kHZ, the efficiency of 92%. Is characterized by frequent changes in the scope of the load, poor working environment. Impact on the current power demand, dynamic characteristics, and no overshoot, load affecting soft-switch nature. 6. Substation in the current operating system switching power supply. For the protection and automatic devices and battery charging. Surge instead of SCR system, the output 10 A, 180 ~ 286V. Main switch IGBT or effective power MOSFET. 7. Single-phase and three-phase rectifier high power factor (with the number of active power correction). One can see that20 of 30, China's switching power supply applications and technical performance of great progress, and the family foundation is closely related to industry and enhance the national strength, and international advanced technology affecting the power switch. China fully demonstrated the power of talent and technical personnel of the entrepreneurial spirit of arduous struggle. In the 1990s, small and medium-sized (500 W below) AC-DC and DC-DC switching power supply is characterized by: high frequency of (switching frequency of 300-400 kHZ) to achieve high power density, a small amount of light; to efficient and reliable; Low-cost, low output voltage (≤3 V; AC input with a few high-power, etc. In the next five years will continue along these directions. Main technical marks from a technical perspective, for several decades to promote switching power supply performance and constantly improve the technological level This should mark is: 1. A new high-frequency power semiconductor devices to achieve the development of high-frequency switching power supply may have. IGBT such as power MOSFET and has been fully replace the power transistor and SCR, so that small and medium-sized switch power下作Frequency of up to 400 kHZ (AC-DC) and 1 MHZ (DC-DC) level. Ultrafast restore power diode, MOSF ET asked further rectification technology for the development of efficient low-voltage output (for example, 3 V) switching power supply for a possible . Are now exploring the development of high-performance high temperature carbonation power to block conductor devices 2. Soft-switch technology enables efficient high-frequency converter with the realization may be. PWM switching power supply switch-mode by hard work (on / off process BU voltage drop / rise and the current rise / fall waveform is overlap), thus the switching losses. High-frequency switching power supply can reduce the volume of weight, but switching losses are greater (power and frequency is directly proportional). So we must Switching on power than / current wave of cross more technology, the so-called zero-voltage (ZVS) / the current (ZCS) switching technology, or soft-switch technology (as opposed to PWM switching technology in terms of hardware), the small soft-switching power supply efficiency Can be increased to 80 a 85 per cent. 1970s, switching power supply market was soft-switch technology laid the foundation. After the new soft-switch technology will continue to emerge, such as the quasi-resonant (1980s) full-bridge phase-shift ZVS-PWM, constant frequency ZVS -PWM/ZCS-PWM (80 in the late) ZVS-PWM active clamp; ZVT-PWM/ZCT-PWM (90 in the early) full-bridge phase-shift ZV-ZCS-PWM (90 years), and so on. China has The latest soft-switching technology to 6 Kw power of communication, efficiency up to 93% 3. Control Technology progress. Such as the current control and multi-loop control, load control, a cycle control, power factor control, DSP control, and the corresponding private Integrated control of the successful development of the chip, so that switching power supply has greatly improved dynamic performance, the circuit also greatly simplified 4. Active Power Mission of Correction (APFC) the development, improve the AC-DC switching power supply power factor. Due to the importation Rectification of a capacitor-a device, AC-DC switching power supply and a large class of the rectifier power supply electronic equipment (such as inverters, UPS), and so the power grid measuring only a few corporations with the APFC 0.65,80 technology can improve To 0.95 to 0.99, both the management of the power grid harmonic "pollution" and also improve the overall efficiency of the power switch. APFC is a single-phase DC-DC converter topology and power factor control of specific applications, while the three-phase APFC Three-Phase PWM switch is rectifier topology and control technology with 5. Magnetic components of new magnetic materials and the development of a new transformer. Such as integrated magnetic circuit, the plane Cores, ultra-thin (Low profile) transformer and a new transformer such as piezoelectric , No Cores printed circuit (PCB) transformer, so that the power switch can reduce the size of the weight of many 6. Capacitors and EMI filter new advances in technology, so that small switching power supply and improve the performance of EMC 7. Micro-processing For monitoring and switching power supply system of internal communication technology applications, improve the reliability of the power system. The late 1990s and made a newswitching power supply of research and development, this is also the new century vision for the development of switching power supply. Such as: an AC - DC converter or regulator to achieve steady flow, and a power factor correction feature, known as single-level (SingleSwitch Single Stage) or 4 S high power factor AC-DC converter output 1 V, 50A of the low-voltage high-current DC-DC converters, also known as voltage regulator module VRM, to adapt to the next generation of ultra-fast microprocessor power supply needs of multi-channel (Multi-Channel or Multi-Phase) DC-DC converter; web server (Server) The switching power supply to be a portable electronic equipment such as the high-frequency switching power supply. More than a brief review of the process of switching power supply development and the performance. I believe the 21st century, the power switch theory and technology development will have a more brilliant achievements , I hope this message of the cross-century youth power experts.开关电源发展轨迹开关电源发展轨迹（察宣兰）开关稳压电源（以下简称开关电源）取代晶体管线性稳压电源（以下简称线性电源）已有30多年历史，最早出现的是串联型开关电源，其主电路拓扑与线性电源相仿，但功率晶体管了作于开关状态后来脉宽调制（PWM）控制技术有了发展，用以控制开关变换器，得到PWM开关电源，它的特点是用20kHz脉冲频率或脉冲宽度调制一PWM开关电源效率可达65～70％，而线性电源的效率只有30一40％。
开关电源电磁干扰及其抑制技术的分析
开关电源电磁干扰及其抑制技术的分析作者：钱忠源来源：《中小企业管理与科技·上中下旬刊》 2018年第10期【摘要】论文的研究内容是明确开关电源产生电磁干扰的危害以及电磁干扰的作用原理，通过分析研究相应的抑制技术，提高开关电源对电磁干扰的阻抗水平。
通过论文的研究得知，阻抗电磁干扰可采用的抑制技术可以从滤波抑制、软开关抑制、屏蔽抗干扰、共模电磁干扰的有源抑制四个方面着手，希望论文的研究能够为我国相关电气工作者提供参考性意见。
【关键词】开关电源；电磁干扰；抑制技术【Keywords】switchingpower supply; electromagnetic interference; suppressiontechnology【中图分类号】TN86 【文献标志码】A 【文章编号】1673-1069（2018）10-0135-021 引言目前我国的开关电源正呈现小型化、高频化的发展趋势，其在电磁兼容性上具有优异表现。
由于开关电源在正常运行工作的情况下，会产生较为严重的电磁干扰，其对电网会造成一定程度的污染，并且对电气设备的安全使用产生极大的危害。
因此，进行开关电源对电磁干扰的阻抗研究时，应采用科学、合理的抑制技术，以此有效防范电磁干扰，保证电气设备能够稳定运行，保障电网系统性能的稳定、高效。
鉴于此，本文的研究不仅对提高我国开关电源阻抗电磁干扰水平具有理论意义，同时还对提高我国电网稳定运行水平具有现实意义。
2 开关电源产生电磁干扰的危害电磁兼容性不足是开关电源产生电磁干扰的主要原因，电磁兼容性不足使得电子设备电磁的辐射传导电路受损，进而产生电磁干扰。
在现今开关电源小型化、高频化的发展趋势之下，开关电源自身的噪声源也会产生大量的传导性电磁干扰，这些电磁干扰将对电子系统及设备造成不良影响[1]。
大量传导性电磁干扰的出现将造成空间人为电磁干扰能量的大数额增长，并且日益恶化的电磁环境对社会日常的生产活动造成较大的损失。
英文翻译及文献电子电子功率半导体
英文翻译及文献电子电子功率半导体I. IntroductionSolid state semiconductor switches are very inviting to use at pulsed power systems because these switches have high reliability, long lifetime, low costs during using, and environmental safety due to mercury and lead are absent. Semiconductor switches are able to work in any position, so, it is possible to design systems as for stationary laboratory using, and for mobile using. Therefore these switches are frequently regarded as replacement of gas-discharge devices – ignitrons, thyratrons, spark gaps and vacuum switches that generally use now in high-power electrophysical systems including power lasers.Traditional thyristors (SCR) are semiconductor switches mostly using for pulse devices. SCR has small value of forward voltage drop at switch-on state, it has high overload capacity for current, and at last it has relatively low cost value due to the simple bipolar technology. Disadvantage of SCR is observed at switching of current pulses with very high peak value and short duration. Reason of this disadvantage is sufficiently slow process of switch-on state expansion from triggering electrode to external border of p-n junction after triggering pulse applying. This SCR feature is defined SCR using into millisecond range of current switching. Improvement of SCR pulse characteristics can be reached by using of the distributed gate design. This is allowed to decrease the time of total switch-on and greatly improve SCR switching capacity. Thus, ABB company is expanded the semiconductor switch using up to microsecond range by design of special pulse asymmetric thyristors (ASCR). These devices have distributing gate structure like a GTO. This thyristor design and forced triggering mode are obtained the high switching capacity of thyristor (p I =150kA, p T =50μs, di/dt = 18kA/μs, single pulse). However, in this design gate structure is covered large active area of thyristor (more than 50%) that decrease the efficiency of Si using and increase cost of device.Si-thyristors and IGBT have demonstrated high switching characteristics at repetitive mode. However, such devices do not intend for switching of high pulse currents (tens of kiloamperes and more) because of well-known physical limits are existed such as low doping of emitters, short lifetime of minority carriers, small sizes of chips etc.Our investigation have obtained that switches based on reverse – switched dinistors are more perspective solid-state switches to switch super high powers at microsecond and submillisecond ranges. Reverse –switched dinistors (RSD) is two-electrode analogue of reverse conducting thyristor with monolithical integrated freewheeling diode in Si. This diode is connected in parallel and in the back direction to the thyristor part of RSD. Triggering of RSD is provided by short pulse of trigger current at brief applying of reversal voltage to RSD. Design of RSD is made thus that triggering current passes through diode areas of RSD quasiaxially and uniformly along the Si structure area. This current produces the oncoming injection of charge carriers from both emitter junctions to base regions and initiates the regenerative process of switch-on for RSD thyristor areas. Such method of triggering for this special design of Si plate is provided total and uniform switching of RSD along all active area in the very short time like as diode switch-on. The freewheeling diode integrated into the RSD structure could be used as damping diode at fault mode in the discharge circuit. This fault mode such as breakdown of cable lines can lead to oscillating current through switch..It has been experimentally obtained in that semiconductor switches based on RSD can work successfully in the pulsed power systems to drive flash lamps pumping high-power neodymium lasers. It was shown in that RSD-switches based on RSD wafer diameter of 63 mm (switch type KRD-25-100) and RSD-switches based on RSD wafer diameter of 76 mm (switch type KRD-25-180) can switch the current pulses with submillisecond duration and peak value of 120 kA and 180 kA respectively. Three switches (switch type KRD – 25-180) connected in parallel were successfully tested under the following mode: operating voltage V= 25 kV, operating current Ip = 470 kA, and transferred charge Q = 145 Coulombs.oDuring 2000 – 2001, the capacitor bank for neodymium laser of facility LUCH was built at RFNC-VNIIEF. This bank including 18 switches type KRD-25-100 operates successfully during 5 years without any failures of switches.This report is submitted results of development of new generation of solid state switches having low losses of power and high-current switching capacity.II. Development of RSD’s next generationThe technology of fabrication of new RSD structure has been developed to increase theswitching capacity. This new structure is SPT (Soft Punch Through)-structure - with “soft” closing of space-charge region into buffer n'-layer.Decreasing of n-base thickness and also improving of RSD switch-on uniformity by good spreading of charge carriers on the n'-layer at voltage inversion are provided decreasing of all components of losses energy such as losses at triggering, losses at transient process of switch-on, and losses at state-on. Our preliminary estimation was shown that such structure must provide the increasing of operating peak current through RSD approximately in 1.5 times.Investigations were carried out for RSD with blocking voltage of 2.4 kV and Si waferdiameters of 63, 76, and 100 mm by special test station. The main goal of these investigations is definition of maximum permissible level of peak current passing through single RSD with given area. Current passing through RSD and voltage drop on RSD structure during current passing are measured at testing. In Fig.1 waveforms of peak currents and voltage drops is shown for RSD with size of 76 mm and blocking voltage of 2.4 kV.Fig.1. Waveforms of pulse current (a) and voltage drop (b) for RSD with wafer size of 76 mm andblocking voltage of 2.4 kVIn according with study program current was slowly increased until maximum permissible level Ipm. When this level was reached the sharp rise of voltage and than thesame sharp decay of voltage for curve U(t) was observed. Reason of voltage rise is strong decreasing of carrier mobility at high temperature, and reason of voltage decay is quick modulation of channel conductivity by thermal generated plasma that is appeared in accordance with sharp exponential dependence for own concentration of initial silicon into base areas of RSD at temperature of 400 – 0600C.Tests were shown that this sharp rise of voltage at maximum permissible current does not lead to immediate fault of RSD. RSD keeps its blocking characteristic. However, after passing of such current pm I we can observe the appearance of erosion from cathode for aluminum metallization of RSD contacts, and this fact is evidence of borderline state of device. The subsequent increasing of current (more than pm I ) leads to fusing of Si structure. Therefore, level Ipm is the reference position to define the value of operation peak current for RSD-switch under long and repeated many times operating mode.We have determined that operating peak current pw I must be less than 80% from level pm I . This ratio was confirmed by calculations and results of tests under pw I mode (several thousands of shots).Data of test results for new generation of RSD with the various diameter of Si wafer are shown in Table 1. In this Table for comparing results of the same tests for the first generation of RSD with size of 63 and 76 mm are shown.III. Switches based on RSD of new generationNew reverse – switched dinistors is manufactured in two variants. RSD of the first variant is in the low-profile metal-ceramic housing. The second variant is RSD fabricated without housing and with additional protection of periphery area from external action.Dinistors placed into housing can be used for work under as mono - pulse mode and repeated - pulse mode. If repeated-pulsed mode using the forced cooling of semiconductor devices and using of heatsinks to both side of pellet must be made. Dinistors without housing connects in series, and such assembly could be placed into a single compact housing. However, such assembly can work under mono-pulse mode only.Operating voltage for switch typically exceeds blocking voltage of single RSD (BO U ≤2400V), thus switch is included several RSDs connected in series. Fig.2. Reverse –switched dinistors for peak current from 200 kA to 500 kA and blocking voltage of 2400 V , encapsullated in hermetic metal – ceramic housing and without housing (RSD sizes of 64, 76, and 100 mm).Number of RSDs included in assembly depends on operating voltage of switch. Therefore, technical problem of switch development is mainly optimization of design for assembly of several dinistors connected in series. A lot of special investigations have carried out such as choice of optimum materials to provide best contacts between RSDs, calculation of dynamic forces to clamp assembly, etc. These investigations are provided small and stable transition electrical and thermal resistances between RSDs that guarantees long and reliable performance of switch. Especial computer technique has developed to select RSDs for connection in series. At this RSD selection value of leakage current and stability of blocking volt-amps diagram are measured especially. This selection technique is allowed exclude the voltage dividers using for equalization of static voltage for each RSD at assembly. Thus, after such selection switch design can simplify, sizes of switch are increased approximately in 1.5 times, and cost of switch is increased too.This solid state switch has operating voltage of up to 25 kVdc, operating peak current of up to 300 kA at current pulse duration of up to 500 μs. RFNC -VNIIEF plans to use such switch at capacitor bank of laser facility “I skra-6”. This switch is included 15 RSDs with size of 76 mm and blocking voltage of 2.4 kV connected in series and encapsullated into dielectric housing. Very high level of switched power density per volume unit has reached by this switch design. This value is of 2.5 610W/3cm , and this value is exceeded in the several times the same switches based on pulse thyristors.Triggering of all RSDs in switch is provided by the single trigger generator which connected to switch in parallel. Triggering current passes simultaneously through all RSDs connected in series. Such triggering type is allowed to increase efficiency and reliability of triggering circuit for this switch, and this is one more advantage of RSD –switch compared toswitch based on thyristors.For new generation of RSD trigger current has peak value between 1-1.5 kA at pulse duration between 1.5 –2 μs. These values are less in 2-3 times compared to values of trigger current for RSD of the first generation.IV. ConclusionNext generation of reverse-switched dinistors and RSD – switches has been developed Tests of these switches are shown that all –time high level of switched power density per volume unit has reached. The switches are able to work under as mono-pulse and pulse-repeated modes and suitable for many applications of pulsed power.应用于脉冲电源设备的新一代高功率半导体关闭开关1 导言固态半导体开关普遍使用在脉冲功率系统，由于这些开关具有可靠性高，寿命长，使用成本低，同时由于汞与铅的量少能够保证环境的安全。
开关电源英文原著对应中文翻译
TOP200-4/14TOPSwitch系列三端离线式PWM开关产品的优点离散开关的低成本替代品• 比其他产品少20到50个组件-降低了成本，提高了可靠性• 源连接选项卡和受控导通的MOSFET可以降低电磁干扰，减少电磁干扰滤波的成本• 在重量和体积方面减少了50%• 在功率超过5瓦的领域内有较强的低耗能竞争力高达90％的反激拓扑效率• 内置启动和电流限制减少直流损耗• 低电容700 V的MOSFET削减交流损耗• CMOS控制器/栅极驱动器功耗仅为6毫瓦• 70％的最大占空比减少传导损耗简化设计缩短上市时间• 支持多种参考设计板• 将PWM控制器和700 V的MOSFET集成在符合行业标准的3引脚TO-220封装里• 只需一个外部电容用作补偿、分路器和启动/自动重启职能系统级故障保护特点• 自动重启和逐周期电流限制功能能够同时处理初级和次级故障• 片上闭锁热关机功能能够防止系统过载高度通用性• 实现降压、升压、反激或转移拓扑结构• 可轻松地与光电元件和初级反馈进行联接• 支持连续或间断的运作模式描述TOPSwitch系列（仅用三个引脚）实现了离线开关式控制系统所必需的所有功能：带受控导通门驱动器的高压N沟道功率MOSFET ；集成了100KHz振荡器的电压模式PWM控制器；高压启动偏置电路；基准电压参考点；偏置并联稳压器/误差放大器用于环路补偿和故障保护电路。
相比离散的MOSFET和控制器或自振荡（RCC）开关转换器的解决方案，TOPSwitch集成电路可以降低总成本，元件数量，尺寸，重量同时提高了效率和系统的可靠性。
这些设备用于在0到100瓦（普通0到50瓦）范围内提供100/110/230伏离线电源和在0到150瓦范围提供230/277伏离线功率因数校正（PFC）功能。
图1 典型应用图2 功能块图引脚功能描述漏引脚输出MOSFET的漏极连接。
在启动过程中通过一个内置的开关高压电流源提供内部偏置电流，内部电流检测点。
开关电源电磁兼容性试验的问题及整改
开关电源电磁兼容性试验的问题及整改丁华【摘要】对某型开关电源的电磁兼容性试验进行研究，为解决该电源在电磁兼容性试验中出现的电磁干扰问题，分析产生的原因及机理，提出了滤波、屏蔽等相应的解决措施。
试验结果表明，该措施有效地解决了开关电源传导发射和辐射发射的超标，提高了产品的电磁兼容性，对类似产品的电磁兼容性设计也具有一定的指导意义。
%To resolve the EMI(electromagnetic interference) of the switching power supply during the EMC(electromagnetic compatibility) test ,the test results and the mechanism of EMI were analysed. Afterwards,the corresponding solutions such as filtering and shielding were thrown out. The results of the test indicate that the solutions effectively restrain the overstandard of conducted emission and radiated emission. The solutions enhance the EMC of switching power supply ,and there is some guidance to the similar produces on EMC design.【期刊名称】《上海计量测试》【年(卷),期】2015(000)002【总页数】3页(P41-42,45)【关键词】开关电源;电磁兼容;滤波;屏蔽【作者】丁华【作者单位】中国电子科技集团公司第38研究所【正文语种】中文开关电源被誉为高效节能电源，它代表着稳压电源的发展方向，现已成为主流产品。
电力系统故障毕业论文中英文资料外文翻译文献
Faults on Power SystemsEach year new design of power equipment bring about increased reliability of operation. Nevertheless, equipment failures and interference by outside sources occasionally result in faults on electric power systems. On the occurrence of a fault , current an voltage conditions become abnormal, the delivery of power from the generating station to the loads may be unsatisfactory over a considerable area, and if the faulted equipment is not promptly disconnected from the remainder of the system, damage may result to other pieces of operating equipment.A faulty is the unintentional or intentional connecting together of two or more conductors which ordinarily operate with a difference of potential between them. The connection between the conductors may be by physical metallic contact or it may be through an arc. At the fault, the voltage between the two parts is reduced to zero in the case of metal-to-metal contacts, or to a very low value in case the connection is through an arc. Currents of abnormally high magnitude flow through the network to the point of fault. These short-circuit currents will usually be much greater than the designed thermal ability of the condition in the lines or machines feeding the fault . The resultant rise in temperature may cause damage by the annealing of conductors and by the charring of insulation. In the period during which the fault is permitted to exist, the voltage on the system in the near vicinity of the fault will be so low that utilization equipment will be inoperative. It is apparent that the late conditions that exist during a fault, and provide equipment properly adjusted to open the switches necessary to disconnect the faulted equipment from the remanding of the system. Ordinarily it is desirable that no other switches on the system are opened, as such behavior would result in unnecessary modification the system circuits.A distinction must be made between and an overload. An overload implies only that loads greater than the designed values have been imposed on system. Under such a circumstance the voltage at the overload point may be low, but not zero. This undervoltage condition may extend for some distance beyond the overload point into the remainder of the system. The current in the overload equipment are high and may exceed the thermal design limits. Nevertheless, such currents are substantially lower than in the case of a fault. Service frequently may be maintained, but at below-standard voltage.Overloads are rather common occurrences in homes. For example, a housewife might plug five waffle irons into the kitchen circuit during a neighborhood part. Such an overload, if permitted to continue, would cause heating of the wires from the power center and might eventually start a fire. To prevent such trouble, residential circuits are protected by fuses or circuit breakers which open quickly when currents above specified values persist. Distribution transformers are sometimes overloads as customers install more and more appliances. The continuous monitoring of distribution circuits is necessary to be certain that transformers sizes are increased as load grows.Faults of many types and causes may appear on electric power systems. Many of us in our homes have seen frayed lamp cords which permitted the two conductors of the cord to come in contact with each other. When this occurs, there is a resulting flash, and if breaker or fuse equipment functions properly, the circuit is opened.Overhead lines, for the most part, are constructed of bare conductors. There are sometimes accidentally brought together by action of wind, sleets, trees, cranes, airplanes, or damage to supporting structures. Overvoltages due to lighting or switching nay cause flashover of supporting or from conductor to conductor. Contamination on insulators sometimes results in flashover even during normal voltage conditions.The conductors of underground cables are separated from each and from ground by solid insulation, which nay be oil-impregnated paper or a plastic such polyethylene. These materials undergo somedeterioration with age, particularly if overloads on the cables have resulted in their operation at elevated temperature. Any small void present in the body of the insulating material will results in ionization of the gas contained therein, the products of which react unfavorably with the insulation. Deterioration of the insulation may result in failure of the material to retain its insulating properties, and short circuits will develop between the cable conductors. The possibility of cable failure is increased if lightening or switching produces transient voltage of abnormally high values between the conductors.Transformer failures may be the result of insulation deterioration combined with overvoltage due to lightning or switching transients. Short circuit due to insulation failure between adjacent turns of the same winding may result from suddenly applied overvoltage. Major insulation may fail, permitting arcs to be established between primary and secondary windings or between winding and grounded metal parts such as the core or tank.Generators may fail due to breakdown of the insulation between adjacent turns in the same slot, resulting in a short circuit in a single turn of the generator. Insulation breakdown may also occur between one of the winding and the grounded steel structure in which the coils are embedded. Breakdown between different windings lying in the same slot results in short-circuiting extensive section of machine.Balanced three-phase faults, like balanced three-phase loads, may be handled on a lineto-neutral basis or on an equivalent single-phase basis. Problems may be solved either in terms of volts, amperes, and ohms. The handing of faults on single-phase lines is of course identical to the method of handing three-phase faults on an equivalent single-phase basis.Faults may be classified as permanent or temporary. Permanent faults are those in which insulation failure or structure failure produces damage that makes operation of the equipment impossible and requires repairs to be made. Temporary faults are those which may be removed by deenergizing the equipment for a short period of time, short circuits on overhead lines frequently are of this nature. High winds may cause two or more conductions to swing together momentarily. During the short period of contact. An arc is formed which may continue as long as line remains energized. However, if automatic equipment can be brought into operation to service as soon as the are is extinguished. Arcs across insulators due to overvoltages from lighting or switching transients usually can be cleared by automatic circuit-breaker operation before significant structure damage occurs.Because of this characteristic of faults on lines, many companies operate following a procedure known as high-speed reclosing. On the occurrence of a fault, the line is promptly deenergized by opening the circuit breakers at each end of the line. The breakers remain open long enough for the arc to clear, and then reclose automatically. In many instances service is restored in a fraction of a second. Of course, if structure damage has occurred and the fault persists, it is necessary for the breakers to reopen and lock open.电力系统故障每年新设计的电力设备都使系统的可靠性不断提高，然而，设备的使用不当以及一些偶然遇到的外在因素均会导致系统故障的发生。
信息工程专业基于单片机的开关电源大学毕业论文外文文献翻译及原文
毕业设计（论文）外文文献翻译文献、资料中文题目：基于单片机的开关电源文献、资料英文题目：文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：信息工程班级：姓名：学号：指导教师：翻译日期： 2017.02.14本科毕业设计(论文)外文参考文献译文及原文学院信息工程学院专业信息工程年级班别学号学生姓名指导教师目录译文 (1)基于单片机的开关电源 (1)1、用途 (1)2、简介 (1)3、分类 (2)4、开关电源的分类 (3)5、技术发展动向 (4)6、原理简介 (6)7、电路原理 (7)8、DC/DC变换 (8)9、AC/DC变换 (8)原文 (10)The design Based onsingle chip switching power supply (10)1、uses (10)2、Introduction (10)3、classification (11)4、the switching power supply. (13)5、technology developments (14)6、the principle of Introduction (17)7、the circuit schematic (18)8、the DC / DC conversion (19)9, AC / DC conversion (20)译文基于单片机的开关电源1、用途开关电源产品广泛应用于工业自动化控制、军工设备、科研设备、LED 照明、工控设备、通讯设备、电力设备、仪器仪表、医疗设备、半导体制冷制热、空气净化器，电子冰箱，液晶显示器，LED灯具，通讯设备，视听产品，安防，电脑机箱，数码产品和仪器类等领域。
2、简介随着电力电子技术的高速发展，电力电子设备与人们的工作、生活的关系日益密切，而电子设备都离不开可靠的电源，进入80年代计算机电源全面实现了开关电源化，率先完成计算机的电源换代，进入90年代开关电源相继进入各种电子、电器设备领域，程控交换机、通讯、电子检测设备电源、控制设备电源等都已广泛地使用了开关电源，更促进了开关电源技术的迅速发展。
开关电源的电磁干扰研究与对策
４．２ 造成电容器的过载故障
电容器的容性阻抗随频率的增加而下降，而其负载阻抗 通常是感性的，随频率的增高而增大；当谐波电流的频率升 高到使电容器的容性阻抗与负载的感抗相近或相等时，会产 生谐振，引起电流增大，造成电容器的过载故障。
４．３ 谐波引起电力系统功率因数降低
由于开关电源的接入，电力系统中除了基波电流外，还
上述缺点，如图 ３ 所示。与典型 ＰＦＣ 主电路不同的是此电路 选用了无损吸收缓冲网络。该网络降低了开关管的开关损 耗，提高了稳定性，延长了使用寿命。它利用一组无源元件 使开关管实现了零电流开通和零电压关断，提高了电源的工 作效率，且相对于其他谐振软开关电路来说降低了生产成 本。下面分析 ＰＦＣ 主开关 Q 的工作过程来说明无损吸收网 络的工作原理。
１、Q 导通 （１） Q 导通时，L２ 电感中的电流不能突变，且 C２、C１ 两 端的电压不能突变，因此 Q 中的电流从零开始缓慢增加，通 过 VD４ 的电流 iVD ４ 逐渐减小。实现零电流开通，导通损耗很 小。 （２） 当电流 iVD ４ 减小为零时，VD４ 进入反向恢复状态， 通过电感 L２ 的电流 iL２＝iL１＋irVD ４。其中 irVD ４ 为 VD４ 的反向电流， 它的变化率受电感 L２ 的控制，反向恢复损耗降低。 （３） 主电感 L２ 中的电流缓慢增加，Ｑ 上的电压 UQ 下降， 电容 C２ 中的电荷通过 VD２、C１、L２、Q 放电，C２ 两端的电压 UC２ 下降。 （４） UC２ 当下降为零时，C２ 中的能量完全转移到 C１ 和 L２ 中。L２ 中的电流饱和不变，UQ 下降为零，Q 完成零电流开通 过程。 （５） Q 保持开通状态，与普通 ＰＦＣ 电路的开关管状态相同。
（３） 由高频变压器的初级线圈、开关管和滤波电容构成 的高频开关电流回路可能产生较大的辐射干扰。同时，若滤 波电容的滤波不足或高频特性不好，则高频电流通过一次整 流回路以差模干扰的方式进入电网。
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(文档含英文原文和中文翻译)中英文翻译外文资料（原文）Modeling, Simulation, and Reduction of Conducted Electromagnetic Interference Due to a PWM Buck Type Switching Power Supply IAbstract:Undesired generation of radiated or conducted energy in electrical systems is called Electromagnetic Interference (EMI). High speed switching frequency in power electronics converters especially in switching power supplies improves efficiency but leads to EMI. Different kind of conducted interference, EMI regulations and conducted EMI measurement are introduced in this paper. Compliancy with national or international regulation is called Electromagnetic Compatibility (EMC). Power electronic systems producers must regard EMC. Modeling and simulation is the first step of EMC evaluation. EMI simulation results due to a PWM Buck type switching power supply are presented in this paper. To improve EMC, some techniques are introduced and their effectiveness proved by simulation.Index Terms:Conducted, EMC, EMI, LISN, Switching SupplyI. INTRODUCTIONFAST semiconductors make it possible to have high speed and high frequency switching in power electronics []1. High speed switching causes weight and volume reduction of equipment, but some unwanted effects such as radio frequency interference appeared []2. Compliance with electromagnetic compatibility (EMC) regulations is necessary for producers to present their products to the markets. It is important to take EMC aspects already in design phase []3. Modeling and simulation is the most effective tool to analyze EMC consideration before developing theproducts. A lot of the previous studies concerned the low frequency analysis of power electronics components []4[]5. Different types of power electronics converters are capable to be considered as source of EMI. They could propagate the EMI in both radiated and conducted forms. Line Impedance Stabilization Network (LISN) is required for measurement and calculation of conducted interference level []6. Interference spectrum at the output of LISN is introduced as the EMC evaluation criterion []7[]8. National or international regulations are the references for the evaluation of equipment in point of view of EMC []7[]8. II. SOURCE, PATH AND VICTIM OF EMIUndesired voltage or current is called interference and their cause is called interference source. In this paper a high-speed switching power supply is the source of interference.Interference propagated by radiation in area around of an interference source or by conduction through common cabling or wiring connections. In this study conducted emission is considered only. Equipment such as computers, receivers, amplifiers, industrial controllers, etc that are exposed to interference corruption are called victims. The common connections of elements, source lines and cabling provide paths for conducted noise or interference. Electromagnetic conducted interference has two components as differential mode and common mode []9.A. Differential mode conducted interferenceThis mode is related to the noise that is imposed between different lines of a test circuit by a noise source. Related current path is shown in Fig. 1 []9. The interference source, path impedances, differential mode current and load impedance are also shown in Fig. 1.B. Common mode conducted interferenceCommon mode noise or interference could appear and impose between the lines, cables or connections and common ground. Any leakage current between load and common ground could be modeled by interference voltage source.Fig. 2 demonstrates the common mode interference source, commonmode currents Icm1 and Icm2and the related current paths[]9.The powerelectronics converters perform as noise source between lines of the supply network. In this study differential mode of conducted interferenceis particularly important and discussion will be continued considering this mode only.III. ELECTROMAGNETIC COMPATIBILITY REGULATIONSApplication of electrical equipment especially static power electronic converters in different equipment is increasing more and more. As mentioned before, power electronics converters are considered as an important source of electromagnetic interference and have corrupting effects on the electric networks []2. High level of pollution resulting from various disturbances reduces the quality of power in electric networks. On the other side some residential, commercial and especially medical consumers are so sensitive to power system disturbances including voltage and frequency variations. The best solution to reduce corruption and improve power quality is complying national or international EMCregulations. CISPR, IEC, FCC and VDE are among the most famous organizations from Europe, USA and Germany who are responsible for determining and publishing the most important EMC regulations. IEC and VDE requirement and limitations on conducted emission are shown in Fig. 3 and Fig. 4 []7[]9.For different groups of consumers different classes of regulations could be complied. Class A for common consumers and class B with more hard limitations for special consumers are separated in Fig. 3 and Fig. 4. Frequency range of limitation is different for IEC and VDE that are 150 kHz up to 30 MHz and 10 kHz up to 30 MHz respectively. Compliance of regulations is evaluated by comparison of measured or calculated conducted interference level in the mentioned frequency range with the stated requirements in regulations. In united European community compliance of regulation is mandatory and products must have certified label to show covering of requirements []8.IV. ELECTROMAGNETIC CONDUCTED INTERFERENCE MEASUREMENTA. Line Impedance Stabilization Network (LISN)1-Providing a low impedance path to transfer power from source to power electronics converter and load.2-Providing a low impedance path from interference source, here power electronics converter, to measurement port.Variation of LISN impedance versus frequency with the mentioned topology is presented in Fig. 7. LISN has stabilized impedance in the range of conducted EMI measurement []7.Variation of level of signal at the output of LISN versus frequency is the spectrum of interference. The electromagnetic compatibility of a system can be evaluated by comparison of its interference spectrum with the standard limitations. The level of signal at the output of LISN in frequency range 10 kHz up to 30 MHz or 150 kHz up to 30 MHz is criterion of compatibility and should be under the standard limitations. In practical situations, the LISN output is connected to a spectrum analyzer and interference measurement is carried out. But for modeling and simulation purposes, the LISN output spectrum is calculated using appropriate software.外文资料（译文）基于压降型PWM开关电源的建模、仿真和减少传导性电磁干扰摘要：电子设备之中杂乱的辐射或者能量叫做电磁干扰(EMI)。