电力专业英语2实用电力英语全解课件

1、电力专业英语2 -实用电力英语电气工程学院1专业英语的语法特点惯用时态。专业英语中多用动词的现在时，尤其是多用一般现在时，来叙述事实或真理，客观地表述定义、定律、定理方程式、公式、图标等。用一般过去式来介绍试验情况或叙述事物的历史发展经过等。用一般将来时叙述计划要做的工作和预期获得的结果等。大量使用被动语态。专业英语更注重对事实、方法、性能和特性做出客观表述。采用被动语态能更为客观，有助于将读者的注意力在描述的事物、事实、现象或过程上。大量使用非限定动词。在专业英语中，为了描述的明确、简练，多采用不定式短语、分词短语，特别是分词短语应用较多。2大量使用名词及介词短语。同样是为了达到明确和简练的

2、要求，在专业英语中多采用名词和介词短语。条件句较多。专业文献中常需提出假设和推理，因而条件句使用较多。长句较多。由于专业英语的作用是陈述事理、描述过程，它所给出的定义、定理、定律或描述的概念及工艺过程，都必须严谨、准确。由此，与日常英语相比，使用的长句较多。有时一个长句就是一个较长的段落。3长句的翻译翻译长句子时，必须分析清楚原文的结构关系，在理解原文内容的基础上，分清主次，按照时间概念和逻辑顺序重新按汉语习惯加以组合处理，译出的句子既要准确地表达原文，又要符合汉语的习惯。常用的译法有顺译法、倒译法、分译法。顺译法是基本上保留原文的语法结构，依照原文顺序译出。一般地，当原文的语法结构和时间顺序

3、与汉语相同时，可采用顺译法。在翻译过程中，根据具体情况，可增加或省略有关连接词。例如：4No such limitation is placed on an alternating-current machine; here the only requirement is relative motion, and since a stationary armature and a rotating field system have numerous advantages, this arrangement is standard practice for all synchronous ma

4、chines rated above a few kilovolt-amperes.交流发电机不受任何限制，惟一的要求是相对移动，而且由于固定电枢及旋转磁场系统具有许多优点，这种安排是所有额定容量超过几千伏安的同步发电机的标准做法。5顺译法例句（2）For large motors, therefore, a phase-winding rotor is used, with the winding connected at one end to each other and at the other end to slip-rings, thus enabling the resistanc

5、e of the rotor to be varied at will, providing a greater starting torque and some speed control.因此，对于大型电机来说，一般采用相绕组转子，其绕线的一端互相连接，而另一端接于轴的滑环上，这样，可随意改变转子的电阻，从而可提供更大的起动转矩，并可适当控制速度。6倒译法当原文结构层次与汉语相反时，要从英语原文的后面译起，自下而上，逆着原文的顺序翻译，称为倒译法。例如： The resistance of any length of a conducting wire is easily measured

6、 by finding the potential difference in volts between its ends when a known current is flowing .已知导线中的电流，只要求出导线两端电位差的伏特数，就不难测出任何长度的导线的电阻。7倒译法Various machine parts can be washed very clean and will be as clean as new ones when they are treated by ultrasonics, no matter how dirty and irregularly shape

7、d they may be.各种机器零件无论多么脏，形状多么不规则，当它们用超声波处理后，就可以被洗得非常干净，甚至干净得像新的零件一样。8分译法为了汉语表述的方便，可将原文的长句拆开来分别译出。当长句中的主句与从句或介词短语及分词短语等多修饰的词与词之间的关系不是很密切，并且各自具有相对的独立意义时，可分解成几个部分或意思层，然后再按时间顺序、逻辑顺序有机的组合在一起，还可以增减适当的词语以便断句之间的衔接。例如，可添加或利用原文中的总括性词语作为引语，而后分述各个部分；或先将某一短语和从句分出去单独译出，在利用总括性词语把它和主句联系到一起；或先译出原文的要点，再将次要部分作为补充说名译在

8、后面。9Pure science has been subdivided into the physical science, which deals with the facts and relations of the physical world, and the biological science, which investigate the history and working of life on this planet. 理论科学分为自然科学和生物科学。前者研究自然界的各种事物和其相互关系，而后者则探讨地球上生物的发展历史和活动。（先要点，再补充说明）10The reason

9、 that a neutral body is attracted by a charged body is that, although the neutral body is neutral within itself, it is not neutral with respect to the charged body, and the two bodies act as if oppositely charged when brought near each other. 虽然中性物体本身是不带电的，但对于带电体来说，它并非中性，当这两个物体彼此接近时，就会产生极性相反的电荷作用。这就

10、是中性物体被电体吸引的原因。（先分述，再总结）11Power System Introduction Power dispatchingvoltagecurrentactive powerreactive powerstatus of circuit breakersStatus of protective relays电力系统调度12Power DispatchingDispatching regulation on power system: issued in 1993 by State Council.Unified dispatching and hierarchical manag

11、ement: five levels.Branch-grid levelRegional levelCounty levelNational levelProvincial level国调网调省调地调县调13National wide grid dispatchingOperation management of related large-scaled plants500(330)Kv transmission linesLarge-scaled plantsCoordinate economic operation of various branch gridsMedium and sma

12、ll scale plantsDistribution center220 Kv transmission lines500 Kv substationHigh voltage customers220 Kv key substation220 Kv substation110Kv, 35 Kv substation110Kv transmission lines and belowInter-regional connection above 500 KvBranch-grid levelregional levelCounty levelNational levelProvincial l

13、evel14Importance of dispatching automation systemlocalized protective relay and automatic equipmentsProtective relays clear fault as quickly as possible.Exciter control maintains voltage quality and balances reactive power.Load shedding keeps frequency variation within acceptable range.Use local inf

14、ormation. Can clear fault as quickly as possible.Limitation: without consideration of whole power system situation.Centralized dispatching automation systemUse information collected from power plants and substations under the charge of the dispatching center.15Run advanced software using real-time i

15、nformation from power plants and substations.Do fault diagnosis and identification.they are not replaceable by each other, and they are complementary to each other.Power dispatching automation system(调度自动化系统). The task is providing to operators(调度员) all various kinds of real time information of powe

16、r system, making management and dispatching decision to ensure safety and economical operation of power system. Sometimes it is also called EMS (Energy Management System)(能量管理系统)16EMS includes the following power advanced software:Load Forecasting(负荷预测), Automated Generation Control(自动发电控制), State E

17、stimation(状态估计), Transient Stability Analysis(暂态稳定分析), Optimal Power Flow(最优潮流), Dispatcher Training Simulator(调度员培训仿真系统)The basics of these advanced software is SCADA system.17The generator voltages are in the range of 11 to 30kV; higher generator voltages are difficult to obtain because of insulat

18、ion problems in the narrow confines of the generator stator.发电机机端电压范围在11kV至30kV之间。机端电压难以达到更高的原因是由于发电机定子的槽绝缘问题。18Transformers are then used to step up the voltages to the range of 110 to 765kV.由升压变压器将电压升至110kV至765kV。In California the backbone of the transmission system is composed mainly of 500kV, 34

19、5kV, and 230kV three-phase lines. The voltages refer to voltages from line to line.加州的主干输电网由500kV、345kV和230kV的三相线路组成。上述电压指的是线电压。19One reason for using high transmission-line voltages is to improve energy transmission efficiency. Basically, transmission of a given amount of power (at specified power

20、factor) requires a fixed product of voltage and line current. Lower line currents are associated with lower resistive losses(I2R) in the line.采用高输电线电压的原因之一是提高能量传输效率。基本上，当传输一定的功率时（在给定功率因数下），电压和线路电流的乘积一定。降低电流相当于降低线路上的电阻性损耗。20The primary objective of the interconnection is improved service reliability; a loss of generation in one area can be made up by utilizing spare capacity in another area.电网互联的主要目的是提高供电可靠性；一个区域损失的发电量可以由另外一个区域的剩余容量供给。21Bad transl