电气工程及其自动化专业英语期末复习资料整理

1、This simple circuit made up of a source,a load and two wires is seldom,if ever,met with in practice.Practical circuits may contain a large number of sources and loads interconnected in a variety of ways.这种由一个电源、一个负载和两根导线组成的简单电路，在实践中即使能 碰到也是很少见的。实际电路可能包括许多按不同方式 连接的电源和负载。The direct ion of curre nt flo

2、w may be show n either by a hollow arrowhead or by suppl ying the curre nt symbol with a double subscriptwhose first digit identifies the junction at a higher potential and the second 省略了 identifies) the junction at a lower potential.电流的方向既可用一个空心箭头来表示，又可用带有双下标的电流符号来表示，且第一个下标认定为高电位点，第二个下标为低电位点。In a p

3、ote ntial-distributi on diagram it is represe nted( on a suitable scale)by the slopeof the respective curve at any poi nt,the slope bei ng defi ned as the tangent of the angle that the line tangent to the curve at that point make with the x-axis.在电势分布图中，电流由曲线上该点相应的 斜率表示，斜率定义为切线与x坐标轴夹角的正切。It follow t

4、hat the r.m.s.(effective) value of an alternating current is numerically equal to the magnitude of the steady direct curre nt that would produce the same heat ing effect in the same resista nee and over the same period of time.由此得出：交流电流的均方根(有效值)大小上等于在相同电阻上和同一时间内产生相同的热 效应的恒稳直流电流。The operational volta

5、ge amplifier is representedschematically by the triangular symbol .AO is the voltage gain from differe ntial in put to sin gle-e ndrd output and is always a positive nu mber . Phase reversals are taken into account at the in put termi nal， which is the reas on why these are labeled ” +” andThe volta

6、ge at each terminal，including the output ,may be referred to common reference ,usually ground ,and uni ess otherwise stated ,this com mon refere nee will be assumed . Thus ,lett ing V(+) represe nt the voltage of the positive in put term inal with respect to the com mon refere nee ,and V(-),that of

7、the n egative in put term inal ,we may defi ne the differential input voltage as V 二V( ) -V (-) ,and the output voltage is V0 = A0Vid.电压运算放大器可用三角形符号来表示。A0表示从差动输入端到单一输出端的电压增益，并恒为正值。考虑到在输入端可能会有反相输入的情况，所以要标上“ +号与号。每个端口包括端口的输出端口的电压，都可以选一个共同的参考点，通常选大地，除非另有说明，否则所假 定的参考点就是地。这样，用 V(+)代表正向输入端对参考点的电压，而V(-)则代表

8、负向输入端对参考点的电压，我们可以将差动输入电压定义为二V)-V(-)，输出电aa压V。二Ay。The significance of this result is that the terminal voltage gain ,which is the usable voltage gain , is in depe ndent of the parameters of the amplifier ,and depe nds only on the exter nal comp onent R1 and 这个结论的意义在于端电压增益(这是很有用的电压增益)与放大器的参数无关，而只取决于 外部

9、元件R1和R2。A truth table is a list of all of the possible in put variable state combinations of a circuit listed in binary-sequential order with the corresponding output state for each combination listed in an adjace nt colu mn. Tablei shows the binary nu mberacorresponding tothe decimal nu mbers from

10、zero to fiftee n.真值表是这样的一个表格，电路中可能输入的所有不同状态组合按二进制顺序连续排列，输出状态与输入端的每种组合对应，表1表示了与十进制015对应 的二进制数。The truth table is used as the begi nning point in desig ning or an alyz ing a logic circuitThe sequential listing makes it easy to recog nize if any in put comb in ati ons were missed. It is made up of eith

11、er from the problem specificati ons or by seque ntial testi ng of an assembled circuit. A logic equati on can be formulated from the truth table and a logic circuit can be developed from the equation. Truth tables are used in defining the basic AND,OR and NOT functions below在设计或分析一个逻辑电路时，首先要列写真值表。这种

12、连续的表格很容易辨认出是否遗漏了任何一种组合，她可有问题的具体情况或对一集成电路进行连续测试来建立。由真值表可建立 逻辑等式，由此等式就可构造一逻辑电路。在下面定义基本逻辑与”、或”和 非”的函数中就用到了真值表。The logic AND fun cti on can be expa nded to any nu mber of in puts ,simply by appl yin gthe basic defi niti on. Thus a 5-i nput logic AND gate will produce an output only if the in put comb in

13、 atio n ABCDE=11111 exists,and providing the physical circuit will still function properly with that many in put attached.只要运用基本定义，逻辑与函数便可扩展到任意一个输入。因此一个五输入的逻辑与门只有在 ABCDE=11111且具体电路与那些连接的输入量有恰当的函数关系时才等于一。Today moti on con trol is an area of tech no logy that embraces many diverse discipli nes,such as

14、 electrical mach in es,power semic on ductor devices, conv erter circuits,dedicated hardware sig nal electronics,control theory,and microcomputers,more recently,the advent of VLSI/ULSI circuits and sophisticated computer-aided desig n tech niq ues has added nelimen sio nsto the tech no logy.当今世界的运动控

15、制是这么一个综合性的技术领域，其包括诸如电机、电力半导体装置、转换 器电路、专门的硬件信号电子学、控制理论、微型计算机等方方面面的众多技术领域。最近出 现的超大规模集成电路，甚至特大规模集成电路，再加上日渐程序的计算机辅助设计技术出现， 又进一步拓宽了运动控制技术领域新的运用范围。Mechanical motion control systemSound widespread acceptanee in industry since the invention of the steam engine started the first in dustrial revoluti on in ei

16、ghtee nth cen tury,whe n mass in dustry manu facturi ng replaced manu al labor.18世纪蒸汽机的发明开启了第一次工业革命，当时大规模的工业生产化代替了手工劳动，从此 以后，运动机械的运动控制系统便在工业领域得到广泛地应用。The con cept of computer-i ntegrated manu facturi ng(CIM),in which bus in ess decisi ons are tran slated to desig ns, which are the n tran slated to m

17、anu facturi ng through a hierarchy of computers and moti on con trol systems, will become a reality in the n ear future.计算机集成制造的概念，将在不远的将来成为现实，所谓计算机集成制造，就是首先将商务决 策转化为产品设计，然后又通过计算机和运动控制系统将其转化为产品制造Bernd M.Bauma nn has dem on strated the suitability of fuzzy con trol tech niq ues for the power-train ma

18、n ageme nt of hybrid electric vehicles.However,his operati on strategyepresentshow the in dividual comp onents of the drive train will in teract with one ano ther, and emphasizes the mea ns for controlling the power flow： such as ransmissions or clutchesand dependency of the components on each other

19、.Bernd Baumann已经证明了模糊控制技术对混合式电动车的传动的控制是适宜的。然而，更重 要的是其在文中说明了，在驱动系统的整个链条中各部件将会是怎样相互作用的，以及在诸如 传递或提取功率这样的过程中的控制的方法，还有系统中各部件之间的相互依存的关系。The direct-axis synchronous reactanee is the ratio of the fundamental component of reactive armature voltage, due to the fun dame ntal direct-axis comp onent of armature

20、curre nt. to this comp onent of curre nt un der steady-state con diti ons and at rated freque ncy.同步电机的直轴同步电抗，是由电枢反应电流的直轴基波分量所产生的电枢反应基波电压与额 定频率稳态条件下的基波电流分量的比值Major data acquisition and control elements found in substation automation and their typical relati on ship to each other and to corporate dat

21、a in frastructure. Regardless of size and complexity of the n etwork, the basic eleme nt of substati on automati on are gen erally those described in the followi ng subsectio ns主要的数据采集和控制元件，是变电所自动化，及其相互之间的，还有其他共同数 据底层之间的通常关系的基础。无论网络的规模和复杂程度如何，变电所综合自动化系统的基 本要素不外乎如下几点。The purpose of a power system is

22、to deliver the power the customers require in real time, on dema nd, within acceptable voltage and frequency limits, and in a reliable and economic manner. In normal operation of a power system ,the total power generation is balaneed by the total load and transmission losses. The system frequency an

23、d voltage on all the buses are within the required limits, while no overloads on li nes or equipme nt are resulted .However ,loads电力系统运行的目的就是一旦用户需要，便能以适时的、可靠的、经济的方式，向用户按其所 要求的电压和频率的范围提供其所需的电力。在电力系统正常运行时，其所发总电量与负荷及 输电损耗之和是相平衡的。由于线路和设备没有出现过载，因而系统中的所有母线的电压和频 率均在所需的范围之内。然而，负荷总是经常在或大或下的变化，因而必须采取一定控制手段，以使

24、电力系统维持在一个稳定而经济的运行状态。Power system control is very important issue to maintain the normal operation of a system.System voltage levels,frequency,tie-line flows,line currents,and equipment loading must be kept within limits determ ined to be safe in order to provide satisfactory service to the power sys

25、tem customers.翻译：电力系统控制是维持电力系统正常运行非常重要的问题。为了给电力系统的用户提供令 人满意的服务，系统的电压、频率、连接线处的涌流、线电流，以及设备负荷率，必须要限制 在安全的范围之内。AGC is an effective means for power and frequency control in large-scale power systems. In an in terc onn ected power system, the primary objectives of AGC are to regulate freque ncy to the spe

26、cified nominal value and to maintain the in tercha nge power betwee n con trol areas at the scheduled values by adjusted the output of the selected gen erators. This fun ctio n is com mon ly referred to as load-freqe ncy con trol.A sec on dary objective is to distributed cha nge in gen erati on amon

27、g un its to mi ni mize operati ng costs.将电压维持在必需的范围内的难题，又被电力系统的现实复杂化了，这个现实就是系统为其提 供电能负荷的数量不计其数，且为其提供的发电机组的数量也是最大的。当负荷变化时，输电 系统的无功功率的需求也是变化的。由于无功功率不能长距离传输，因而电压控制的功能，就 不得不采用在整个系统中分散布局的某种专用的装置来完成。这就与频率控制时的情形截然相 反，频率控制是取决于系统总的有功平衡的。恰当地选择和布局控制无功功率和电压的装置， 是电力系统工程所面临的主要挑战之一。In an interconnected power syste

28、m,the primary objectives of AGC are to regulate frequency to the specified nominal value and to maintain the interchange power between control area at the scheduled values by adjust the output of the selected gen erators.在相互连接的电力系统中，发电自动化控制的首要的目标有两个，一将频率调节到指定的额定 值，二是通过调节所选定的发电机的输出功率，维持各控制区域之间的计划发电量之间的交换。The problem of maintaining voltages within the required limits is complicated by the fact that the power system supplies power to a vast nu mber of