专业英语 段落翻译(错误已更改)

P1 (1) The voltage across a pure inductor is defined by Faraday ’s law, which states that the voltage across the inductor is proportional to the rate of change with time of the current through the inductor.

纯电感两端的电压是由法拉第定律定义的，法拉第定律指出：电感两端的电压正比于流过电感的电流随时间的变化率。

P5 (2) A three-phase electric circuit is energized by three alternating emfs of the same frequency and differing in time phase by 120 eletrical degrees.

三相电路可由三个频率相同、在时间相位上相差120︒电角度的电动势供电。

P9 (3) One problem with electronic devices corresponding to the generalized amplifiers is that the gains, A U or i A , depend upon internal properties of the two-port system

(i o etc R R μβ，，，，.). This makes design difficult since these parameters usually vary from device to device, as well as with temperature.

对应于像广义放大器这样的电子器件存在的一个问题就是它们的增益AU 或AI 取决于双端口系统(i o etc R R μβ，，，，等)的内部特性。器件之间参数的分散性和温度漂移给设计工作增加了难度。

P31 (4) However, the disadvantage is that they generate harmonics in the utility system creating a power quality problem for other consumers. Besides, thyristor converters constitute a low lagging power factor load on the utility system.

但是，它们的缺点是在电力系统中产生谐波，对其他用户产生供电质量问题。此外，晶闸管变换器给电力系统提供了一个滞后的低功率因数负载。

P36 (5) The permanent-motor has several advantages over conventional types of DC motors. One advantage is reduced operational cost. The speed characteristics of the permanent-magnet motor are similar to those of the shunt-wound DC motor. The direction of permanent-magnet motor can be reversed by reversing the two power lines.

永磁电机相对于常规直流电机有几个优点。优点之一是减少了运行损耗。永磁电机的转速特性类似于并励式直流电机的转速特性。永磁电机的旋转方向可通过将电源线反接来实现。

P40(6) m ω* sets the speed reference. A signal proportional to the motor speed is obtained

from the speed sensor. The speed sensor output is filtered to remove the AC ripple and compared with the speed reference. The speed error is processed through a speed controller. The output of the speed controller c u adjusts the rectifier firing angle α to make the actual speed close to the reference speed.

ωm* 为速度参考值。正比于电机速度的信号可从速度传感器获得。速度传感器的输出

滤除交流波，并与速度参考值比较，速度误差被速度控制器处理，速度控制器的输出uc 调整整流器的触发角α，以使实际的速度接近于参考速度。

P41 (7) Another scheme of closed-loop speed control is shown in Fig. 1-5B-2. It employs an inner current control loop within an outer speed loop. The output of the speed controller

e is

c applie

d to a current limiter which sets th

e current reference

I*for the inner current control

a

loop.

闭环速度控制的另一种示意图如图1-5B-2所示。在外环速度回路中采用内环电流控制回路。速度控制器的输出ec用于电流控制器，为内环电流控制回路设置电流参考值Ia*。

P45 (8) In a wound-rotor machine, the rotor winding is similar to that of the stator, but in a cage machine, the rotor has a squirrel cage-like structure with shorted end rings.

对绕线式转子电机而言，转子绕组与定子绕组类似，但鼠笼式电机的转子具有鼠笼状结构，并且有两个短路环。

P86 (9) With the system transfer function known, the Routh-Hurwitz criterion will tell us whether or not a system is stable. If it is stable, the steady-state accuracy can be determined for various types of inputs.

如果已知系统的传递函数，劳斯-胡尔维茨判据会告诉我们系统是否稳定。如果系统稳定,可以确定各种类型输入时系统的稳态精度。

P87 (10) There are as many as locus branches as there are open-loop poles. A branch starts, for 0

K=, at each open-loop pole. As K is increased, the closed-loop pole positions trace out loci, which end, for K→∞,at the open-loop zeros.

根轨迹的分支数等于开环极点数。当K=0时，分支起始于每一个开环极点。随着K值的增加，闭环极点位置绘出根轨迹，当K→∞时，根轨迹终止于开环零点。

P107 (11) The transition from simple approximate models, which are easy to work with, to more realistic models produces two effects. First, a larger number of variables must be included in the model. Second, a more realistic model is more likely to contain nonlinearities and time-varying parameters.

从易于处理的简单近似模型到实际一些的模型的转换存在着两方面问题。第一，大量的变量必须包含在模型中。第二，更实际的模型更容易包含非线性和时变参数。

P133 (12) The memory of a computer consists of a set of sequentially numbered locations. Each location is a register in which binary information can be stored. The “number” of a location is called its address. The lowest address is 0.

计算机的存储器是由一套连续编号的单元所组成。每个存储单元是一个能存二进制信息的寄存器。单元的编号称为地址。初始地址为0。