/ 9 翻译 P.1 The voltage across a pure inductor is defined by Faraday’law,which states that the voltage across the inductor is proportional to the rate of change with time of the current through the inductor.thus we have U=Ldi/dt. 纯电感电压由法拉第定律定义，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。因此可得到：U=Ldi/dt 式中 di/dt = 电流变化率， 安培/秒； L = 感应系数， 享利。 P.3 A three-phase electric circuit is energized by three alternating emfs of the same frequency and differing in time phase by 120 electrical degrees . 三相电压的产生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。 P.9 One problem with electronic devices corresponding to the generalized amplifiers is that the gains,AU or AI ,depend upon internal properties of two-port system( ).This makes design difficult since these parameters usually vary from device to device ,as well as temperature . 运算放大器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(m、b、RI、Ro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。 P.31
/ 9 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 tha 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。 P.32 Inverter is a device which receives DC voltage at one side and converts it to AC voltage on the other side 逆变器是从一侧接受直流电压，在另一侧将其转换成交流电压的装置。 . Inverter can be classified voltage-fed inverter and current-fed inverter. 逆变器可分成电压源型和电流源型两种。 P.36 The permanent-magnet motor has several advantages over convertional 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 fo rotation of a permanent-magnet moror can be reversed by reversing the twopower 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
/ 9 机的旋转方向可通过将电源线反接来实现 P40 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 UC adjusts the rectifier firing angle A to make the actual speed close to the reference spee
d. 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。 P.45 In a wound-rotor machine,the rotor wingding si 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。 With the system transfer funcion 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
/ 9 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 P.87 There are as many as locus branches as there open-loop poles.A branch srtarts,for K=0,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。 P.107 The transition from simple approximate modles,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产生了两种作用（存在着两个方面的问题）。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。 P.133 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
/ 9 its address.The lowest address is 0. 计算机的内存由一组连续编号的单元构成。每一个单元都是一个存储二进制信息的寄存器。单元的编号称为其地址。最低的地址为0。 P.135 The CPU’s job is to fetch instructions from memory and execute these instructions.The structure of the CPU is shown in Fig.3-1A-3.It has four main components:an arithmetic and logical unit(ALU),a set of registers,an internal processor bus and controller CPU的工作是从存储器中取回指令并执行。它有四个主要部件：算术－逻辑单元，一系列存储器，一个内部处理器总线和控制器. P.163 These two types of architecture are found in single-chip microcomputers.Some employ the split program/data memory of the Harvard architecture,shown in Fig.3-4A-1.others follow the philosophy,
widely adopted for general-purpose computers and microprocessors,of making nological distinction between program and data memory as in the Princeton architecture,shown in Fig-3-4A-2. 单片机有这样两种结构类型。一些使用了哈佛结构的分离的程序/数
/ 9 据存储器，如图3-4A-1所示。另一些被通用计算机和微处理器广泛采用的是普林斯顿结构，遵循在程序存储器与数据存储器之间没有逻辑区别的原理，如图3-4A-2所示。 In general terms a single-chip microcomputer is characterized by the incorporation of all the uints of a computer into a single device,as shown in Fig.3-4A-3. 概括地讲，单片机的特征是将计算机的所有部件都合并到一个单一的装置上,如图3-4A-3.所示。 P.164 RAM is for the storage of working variables and data used during program execution. RAM是用于程序执行过程中对工作变量和数据的存储 P.166 Ａ digtital Signal Processor is a super-fast chip computer,which has been optimized for the detection,processing and generation of real world signals such as voice,video,music,etc,inreal time. 数字信号处理器是一种超高速单片计算机，它已被优化以用于一些现实信号如语音、视频、音乐等等的实时检测、处理和产生。
/ 9 Distinguishing between DSP and micro by application is perhaps not the best way forward after all.In fect,the main difference lies deep inside the divices themselves,in the internal chip architecture,with DSP devices particularly optimized for high-speed,high-accuracy multiplication. 要按应用来分辨DSP与微处理器可能不是最好的方法。实际上，它们两者主要的不同存在于它们的内部芯片结构。DSP器件对高速、高精度的乘法进行了特殊的优化。 P180 Automatic process control is concerned with maintaining process variables,temperatures,pressures,flows,compositions,and the like at some desired operating valur.As we shall see in the ensuing pages,processes are dynamic in nature.Changes are always occurring,and if actions are not taken,the important process variables-those related to safety,product quality,and production rates-will not achieve design conditions. 自动过程控制与持续过程变量、温度、压力、流量、成分和期望操作值一类的量有关。正如我们在后续的章节中所看到的，过程本身是动态的。变化不断发生，并且如果激励未加入，重要的过程变量——与
/ 9 安全有关的变量、产品质量和生产率——将不能获得期望值 P186 There are some other common industrial sensors:pressure,flow,temperature,and level.Sometimes it is important for system analysis to obtain the parameters that describe the sensor/transmitter behavior. 其他工业传感器有：压力、流量、温度和水平面。有时候，获得描述传感器/热敏电阻动态性能的参数对于系统分析是很重要的 汉译英 1.这种仪表用
来测定电池充电的程度。 This instrument is used to determine how fully the batteries are charged. 2.电流的大小与电压成正比，与电阻成反比。 An current varies directly as the voltage force and inversely an the resistance. 3.应当注意报复仪器免受灰尘和潮湿。 Care should be taken to protect the instrument from dust and dump. 4.模糊控制的作用不同于传统的比列积分微分控制。
/ 9 Fuzzy ccntrol acts differently from conventional PID control. 5.铜的导电性良好。 Copper conducts electricity very well. 6.变压器的输出电压为10Kv. The output of transformers has a voltage of 10kilovoltages. 7.如果系统增益超过了一定界限，系统就会不稳定。 If the system gain is increased beyond a certain limit the system will become unstable. 8.这个部门有3台计算机感染了病毒。 The three computers in this section are infected by virus. 9.积分（作用）可以消除闭环系统中的静差（现象）。 Integration can get rid of the static error in closed-loop system.