电气专业中英文翻译

The report concludesThe report mainly collected from the power transmission and power system requirements related to the content of these twoareas, and analyze, to understand some of the relevant knowledge.Page2 Electrical Energy Transmission（电能输送）1 English textFrom reference 1Growing populations and industrializing countries create huge needs for electrical energy. Unfortunately, electricity is not alwaysused in the same place that it is produced, meaning long-distance transmission lines and distribution systems are necessary. Buttransmitting electricity over distance and via networks involves energy loss.So, with growing demand comes the need to minimize this loss to achieve two main goals: reduce resource consumption whiledelivering more power to users. Reducing consumption can be done in at least two ways: deliver electrical energy more efficientlyand change consumer habits.Transmission and distribution of electrical energy require cables and power transformers, which create three types of energy loss:the Joule effect, where energy is lost as heat in the conductor (a copper wire, for example); magnetic losses, where energy dissipates into a magnetic field;the dielectric effect, where energy is absorbed in the insulating material.The Joule effect in transmission cables accounts for losses of about 2.5 % while the losses in transformers range between 1 % and2 % (depending on the type and ratings of the transformer). So, saving just 1 % on the electrical energy produced by a powerplant of 1 000 megawatts means transmitting 10 MW more to consumers, which is far from negligible: with the same energy we cansupply 1 000 - 2 000 more homes.Changing consumer habits involves awareness-raising programmers, often undertaken by governments or activist groups. Simplethings, such as turning off lights in unoccupied rooms, or switching off the television at night (not just putting it into standbymode), or setting tasks such as laundry for non-peak hours are but a few examples among the myriad of possibilities.On the energy production side, building more efficient transmission and distribution systems is another way to go about it. Highefficiency transformers, superconducting transformers and high temperature superconductors are new technologies which promisemuch in terms of electrical energy efficiency and at the same time, new techniques are being studied. These include direct currentand ultra high voltage transmission in both alternating current and direct current modes. Keywords: electrical energy transmissionFrom reference 2Disturbing loads like arc furnaces and thyristor rectifiers draw fluctuating and harmonic currents from the utility grid. These nonsinusoidal currents cause a voltage drop across the finite internal grid impedance, and the voltage waveform in the vicinity becomesdistorted. Hence, the normal operation of sensitive consumers is jeopardized.Active filters are a means to improve the power quality in distribution networks. In order to reduce the injection of non sinusoidalload currents shunt active filters are connnected in parallel to disturbing loads (Fig. 1). The active filter investigated in this projectconsists of a PWM controlled three-level VSI with a DC link capacitor.The VSI is connected to the point of common coupling via atransformer. The configuration is identical with an advanced static var compensator.The purpose of the active filter is to compensate transient and harmonic components of the load current so that only fundamentalfrequency components remain in the grid current. Additionally, the active filter may provide the reactive power consumed by theload. The control principle for the active filter is rather straightforward: The load current ismeasured, the fundamental activecomponent is removed from the measurement, and the result is used as the reference for the VSI output current.In the low voltage grid, active filters may use inverters based on IGBTs with switching frequencies of 10 kHz or more. The harmonicsproduced by those inverters are easily suppressed with small passive filters. The VSI can be regarded nearly as an ideally controllablevoltage source. Inmedium voltage applications with power ratings of several MV A, however, the switching frequen cy of today’s VSIsis limited to some hundred Hertz. Modern high power IGCTs can operate at around 1 kHz. Therefore, large passive filters are neededin order to remove the current ripple generated by the VSI. Furthermore, in fast control schemes the VSI no longer represents anideal voltage source because the PWM modulator produces a considerable dead-time. In this project a fast dead-beat algorithm forPWM operated VSIs is developed [1].This algorithm improves the load current tracking performance and the stability of the activefilter. Normally, for a harmonics free current measurement the VSI currentwould be sampled synchronously with the tips of the triangular carriers. Here, the current acquisition is shifted in order to minimizethe delays in the control loop. The harmonics now included in themeasurement can be calculated and subtracted from the VSIcurrent. Thus, an instantaneous current estimation free of harmonics is obtained.Keywords: active filtersFrom reference 3This report provides background information on electric power transmission and related policy issues. Proposals for changing federaltransmission policy before the 111th Congress include S. 539, the Clean Renewable Energy and Economic Development Act,introduced on March 5, 2009; and the March 9, 2009, majority staff transmission siting draft of the Senate Energy and NaturalResources Committee. The policy issues identified and discussed in this report include:Federal Transmission Planning: several current proposals call for the federal government to sponsor and supervise large scale, on-going transmission planning programs. Issues for Congress to consider are the objectives of the planning process (e.g., a focus onsupporting the development of renewable power or on a broader set of transmission goals), determining how much authority newinterconnection-wide planning entities should be granted, the degree to which transmission planning needs to consider non-transmission solutions to power market needs, what resources theexecutive agencies will need to oversee the planning process, and whether the benefits for projects included in the transmissionplans (e.g., a federal permitting option) will motivate developers to add unnecessary features and costs to qualify proposals for theplan.Permitting of Transmission Lines: a contentious issue is whether the federal government should assume from the states the primaryrole in permitting new transmission lines. Related issues include whether Congress should view management and expansion of thegrid as primarily a state or national issue, whether national authority over grid reliability (which Congress established in the EnergyPolicy Act of 2005) can be effectively exercised without federal authority over permitting, if it is important to accelerate theconstruction of new transmission lines (which is one of the assumed benefits of federal permitting), and whether the executiveagencies are equipped to take on the task of permitting transmission lines.Transmission Line Funding and Cost Allocation: the primary issues are whether the the federal government should help pay for newtransmission lines, and if Congress should establish a national standard for allocating the costs of interstate transmission lines toratepayers.Transmission Modernization and the Smart Grid: issues include the need for Congressional oversight of existing federal smart gridresearch, development, demonstration, and grant programs; and oversight over whether the smart grid is actually proving to be agood investment for taxpayers and ratepayers.Transmission System Reliability: it is not clear whether Congress and the executive branch have the information needed to evaluatethe reliability of the transmission system. Congress may also want to review whether the power industry is striking the right balancebetween modernization and new construction as a means of enhancing transmission reliability, and whether the reliability standardsbeing developed for the transmission system are appropriate for a rapidly changing power system. Keywords: electric power transmissionPage3 Requirements of an Electric Supply System(供电系统需求)1 English textFrom reference1Connections to external 330 kV power grids are provided using an open 330 kV switchyard. The plant is connected to theLithuanian power grid using two transmission lines L-454 and L-453, 330 kV each, to the Belorussian power grid using threetransmission lines L-450, L-452 and L-705, and to the Latvian power grid using one transmission line L-451.Connections to external power grids at 110 kV are provided using the first section of the open 110 kV switchyard. The plant isconnected to the Lithuanian power grid using one transmission line “Zarasai” 110 kV, and to the Latvian power grid using onetransmission line L-632.Connections between the open switchyards at 330 kV and 110 kV are established using two coupling autotransformers AT-1 andAT-2, types ATDCTN- 200000/330. Power of each autotransformer is equal to 200 MV×A. The autotransformers have a device forvoltage regulation under load. The device type is RNOA-110/1000. 15 positions are provided to regulate voltage in a range (115 ±6) kV.The open 330 kV switchyard is designed using "4/3" principle (four circuit breakers per three connections) and consists of twosections. Circuit breakers are placed in two rows. The first section of the open switchyard 110 kV is designed using “Double systemof buses with bypass” structure. The second section of open switchyard 110 kV is connected to the first section through twocircuit breakers C101 and C102. The second section has the same design as the first one. The following transmission lines areconnected to the second section: L-Vidzy, L-Opsa, L-Statyba, LDuk Ötas. These transmission lines are intended for district powersupplies, so they are not essential for electric power supply for the plant in-house operation.Air circuit breakers of VNV-330/3150A type are used in the open 330 kV switchyard. Air circuit breakers of VVBK-110B-50/3150U1type are used in open switchyard 110 kV. To supply power loads on voltage level 330 kV and 110 kV, aerial transmission lines areused. Electrical connections of external grids 110 and 330 kV are presented in Fig. 8.1. Keywords: transmission linesFrom reference 2AbstractThis paper addresses sustainability criteria and the associated indicators allowing operationalization of the sustainability concept in the context of electricity supply. The criteria and indicators cover economic,environmental and social aspects. Some selected results from environmental analysis, risk assessment and economic studies areshown. These studies are supported by the extensive databases developed in this work. The applications of multi-criteria analysisdemonstrate the use of a framework that allows decision-makers to simultaneously address the often conflicting socio-economic andecological criteria. “EnergyGame”, the communication-oriented software recently developed by the Paul Scherrer Institute (PSI),provides the opportunity to integrate the central knowledge-based results with subjective value judgments. In this way a sensitivitymap of technology choices can be constructed in an interactive manner. Accommodation of a range of perspectives expressed inthe energy debate, including the concept of sustainable development, may lead to different internal rankings of the options butsome patterns appear to be relatively robust.IntroductionThe public, opinion leaders and decision-makers ask for clear answers on issues concerning the energy sector and electricitygeneration in particular. Is it feasible to phase out nuclear power in countries extensively relying on nuclear electricity supply andsimultaneously reduce greenhouse gas emissions? What are the environmental and economic implications of enhanced uses ofcogeneration systems, renewable sources and heat pumps? How do the various energy carriers compare with respect to accidentrisks? How would internalization of external costs affect the relative competitiveness of the various means of electricity production?What can we expect from the prospective technological advancements during the next two or three decades? Which systems orenergy mixes come closest to the ideal of being cheap, environmentally clean, reliable and at the same time exhibit low accidentrisks?How can we evaluate and rank the current and future energy supply options with respect to their performance on specificsustainability criteria?The Swiss GaBE Project on “Comprehensive Assessment of Energy Systems” provides answers to many issues in the Swiss andinternational energy arena. A systematic, multidisciplinary, bottom-up methodology for the assessment of energy systems, has beenestablished and implemented. It covers environmental analysis, risk assessment and economic studies, which are supported by theextensive databases developed in this work. One of the analysis products are aggregated indicators associated with the varioussustainability criteria, thus allowing a practical operationalization of the sustainability concept. Apart from technical and economicaspects an integrated approach needs to consider also social preferences, which may be done in the framework of multi-criteriaanalysis.Keywords: criteria indicatorsFrom reference 3Mobility of persons and goods is an essential component of the competitiveness of European industry and services as well as anessential citizen right. The goal of the EU's sustainable transport policy is to ensure that our transport systems meet society'seconomic, social and environmental needs.The transport sector is responsible for about 30% of the total final energy consumption and for about 25% of the total CO2emissions. In particular the contribution of road transport is very high (around 80% and 70% respectively). These simple data shedlight on the necessity to move towards a more sustainable transportation system, but also suggest that a technological/systemicrevolution in the field will positively impact the overall world’s sustainable development.From a technological point of view, a lower dependency from not renewable energy sources (i.e. fuel oil) of the road transport isthe main anticipated change. In particular electric engines possibly represent the natural vehicle evolution in this direction. Indeedthey have much higher energy efficiency (around three times that of internal combustion engines, ICE) and do not produce anykind of tailpipe emissions. How the electricity will be supplied to the vehicles is still unpredictable due to the too many existinguncertainties on the future development, but the electrification of the drive train will contribute to having alternative energy pathsto reduce the nearly total dependency on crude oil. In particular, vehicle range and performances allowed by the differentpossibilities will play a key role on the debate.At the moment a great attention is attracted by electric vehicles, both hybrid and not, that will allow users to recharge theirvehicles directly at home. This kind of vehicle can represent a real future alternative to the ICE vehicles in particular for whatconcerns the daily commuting trips (whose range is quite low). It is therefore important to understand what might be the impacton the electric supply system capabilities of this recharging activity.In this light the present study carries out an analysis of this impact for the Province of Milan (of particular relevant due the very highdaily commuting trips) at a 2030 time horizon. Key issue of the analysis is the estimation of a potential market share evolution for theelectric vehicles. The results obtained show that even with a very high future market penetration the impact of the vehicles on theannual energy consumption will be quite negligible. On the contrary they also show that without an appropriate regulation (e.g. theintelligent integration of electric vehicles into the existing power grid as decentralised and flexible energy storage), they couldheavily impact on the daily electric power requirements.Keywords: electric vehicles报告总结本次报告主要从网上收集了电能输送和供电系统的需求这两个方面的相关内容，并对其进行了分析，了解了一些相关知识。