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PART 1 Electrical and Electronic Engineering Basics UNIT 1 A UNIT 2 A UNIT 3 A UNIT 4 A UNIT 5 A UNIT 6 A UNIT 7 A Electrical Networks ———————————— 3 B Three-phase Circuits The Operational Amplifier ——————————— 5 Logical Variables and Flip-flop —————————— 8 Power Semiconductor Devices —————————— 11 Types of DC Motors —————————————15 AC Machines ———————————————19 Electric Power System ————————————22 B Transistors B Binary Number System B Power Electronic Converters B Closed-loop Control of DC Drivers B Induction Motor Drive B Power System Automation PART 2 Control Theory UNIT 1 A B UNIT 2 A UNIT 3 A UNIT 4 A The World of Control ————————————27 Stability and the Time Response ————————— 30 The Root Locus ————————————— 32 The Transfer Function and the Laplace Transformation —————29 B Steady State————————————————— 31 B The Frequency Response Methods: Nyquist Diagrams ————— 33 The Frequency Response Methods: Bode Piots ————— 34 B Nonlinear Control System 37 UNIT 5 A Introduction to Modern Control Theory B B B PART 3 B B B State Equations Optimum Control Systems Artificial Neural Network Computer Control Technology 42 43 44 Fundamentals of Computer and Networks The Applications of Computers 46 40 38 UNIT 6 A Controllability, Observability, and Stability UNIT 7 A Conventional and Intelligent Control UNIT 1 A Computer Structure and Function UNIT 2 A Interfaces to External Signals and Devices UNIT 3 A PLC Overview PACs for Industrial Control, the Future of Control 1 UNIT 4 A Fundamentals of Single-chip Microcomputer 49 B B PART 4 B B B B PART 5 B B B B PART 6 Understanding DSP and Its Uses Embedded Systems Design Process Control 50 52 53 Fundamentals of Process Control UNIT 5 A A First Look at Embedded Systems UNIT 1 A A Process Control System UNIT 2 A Sensors and Transmitters Final Control Elements and Controllers PID Controllers and Other Controllers Control Panels Control Based on Network and Information Evolution of Control System Architecture Stability of NCSs with Network-induced Delay Virtual Manufacturing—A Growing Trend in Automation Enterprise Resources Planning and Beyond Synthetic Applications of Automatic Technology UNIT 3 A P Controllers and PI Controllers UNIT 4 A Indicating Instruments UNIT 1 A Automation Networking Application Areas UNIT 2 A Fundamental Issues in Networked Control Systems UNIT 3 A Fundamentals of the Database System UNIT 4 A Concepts of Computer Integrated Manufacturing UNIT 1 A Recent Advances and Future Trends in Electrical Machine Drivers B B B System Evolution in Intelligent Buildings A General Introduction to Pattern Recognition Electric Vehicles UNIT 2 A Industrial Robot UNIT 3 A Renewable Energy 2 UNIT 1 A

电路 电路或电网络由以某种方式连接的电阻器，电感器和电容器等元件组成。如果网络不包含能源，如电池或发电机，那么就被称作无源网络。换句话说，如果存在一个或多个能源，那么组合的结果为有源网络。在研究电网络的特性时，我们感兴趣的是确定电路中的电压和电流。因为网络由无源电路元件组成，所以必须首先定义这些元件的电特性。就电阻来说，电压-电流的关系由欧姆定律给出，欧姆定律指出：电阻两端的电压等于电阻上流过的电流乘以电阻值。在数学上表达为： u=iR (1-1A-1)式中 u=电压，伏特；i =电流，安培；R =电阻，欧姆。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。电容两端建立的电压正比于电容两极板上积累的电荷 q 。因为电荷的积累可表示为电荷增量 dq 的和或积分，因此得到的等式为 u=，式中电容量 C 是与电压和电荷相关的比例常数。由定义可知，电流等于电荷随时间的变化率，可表示为 i = dq/dt。因此电荷增量 dq 等于电流乘以相应的时间增量，或 dq = i dt，那么等式(1-1A-3)可写为式中 C =电容量，法拉。

The converter can be improved just by exchanging the position of the resonant inductance and the transformer such that the transformer is connected with the lagging leg. The improved converter has several advantages over its counterpart, e.g., the clamping diodes conduct only once in a switching period, and the resonant inductance current is smaller in zero state, leading to a higher efficiency and reduced duty cycle loss. The operation principle of the improved converter and the comparison with the original converter are analyzed in this paper. The effect of the blocking capacitor in series with the transformer or resonant inductance is discussed, and a best scheme is determined.The improved converter is adopted to design the DC/DC converter of secondary power supply in HVDC power system.

本文将谐振电感和变压器交换位置，使变压器与滞后桥臂相连，这样箝位二极管在一个开关周期中只导通一次，同时零状态时谐振电感电流较小，有利于提高变换效率和减小占空比丢失，本文分析改进后变换器的工作原理，并与改进前的变换器进行对比，讨论隔直电容在不同位置对变换器工作的影响，确定一种最佳工程方案。

The steady-state operating characteristics of the proposed DC-DC converter topology are illustrated and discussed on the basis of the simulation and some experimental results of 2kW-4OHz breadboard set up.

不过，大部分的零电压开关PWM DC - DC变换器发达以前，包括一些弊端，如负荷依赖软开关运作，相对狭小的范围和零电压转换器效率降低，由于大循环电流流经。

This topic uses the switching mode is the entire bridge all controls the rectification filter, moreover the power source has also utilized the soft switch technology, causes its loss to reduce obviously, the DC-DC transformation use cuts the wave boosted circuit to realize, the structure is simple, the transfer efficiency is high; Selects the small breakover resistance, the high shutter speed P60N06 tube for the switching valve, to select the quick recovery diode rectification, reduces the reverse breakover time, reduces the loss.

本课题采用的开关方式是全桥全控整流滤波，而且电源还运用了软开关技术，使它的损耗明显降低，DC-DC变换使用斩波升压电路来实现，结构简单，转换效率高；选用小导通电阻、高开关速度的P60N06管为开关管、选用快速恢复二极管整流，减少反向导通时间，降低损耗。

This DC side APF is shunted at the DC side of rectifier bridge.

该DC侧APF并联在整流桥的直流侧。

So the proposed ZVT-PWM flyback dc/dc converter does not increase active or passive clamper circuit to suppress the switch voltage stress and can reduce switch loss to promote the efficiency of the circuit.

文中详细说明电路之操作原理并推导各个工作模式下的等效电路及转换器设计方法。

Based on the high frequency power amplifier,a class E resonant high frequency DC/DC and a phase-shifted control strategy are proposed in this paper,the converter based on the idea can heighten switching frequency,reduce the loss of the system,widen the range of output.

以高频功率放大器为基础，提出了一种超高频E类谐振DC/DC变换器的移相控制策略，基于这种思想的变换器可以提高开关频率，降低系统损耗，拓宽输出范围。

Simulation results show the surface potential closed to sea drops to zero influenced by sea. The lower potential of substation makes more DC currents of power grid flow through transformer neutrals and causes DC bias of transformers.

靠近海洋层的地表电位受到海洋的影响将下降至接近零电位，导致更多的直流电流从靠近海洋的变压器中性点流出，影响了变压器的正常运行。

Commutation failure is one of the most frequent faults in AC/DC systems and continuous commutation failures will lead to closedown of DC system.

换相失败是交直流输电系统最常见的故障之一，连续的换相失败还会引发直流闭锁，影响系统稳定运行。

In this paper, investigate basic half bridge Three-Level DC/DC converter, the operation and parameter design are disused ,second side commutate diode reverse furbish bring high pinnacle on the main switches.

本文首先给出了基本半桥式三电平DC/DC变换器，详细分析了其工作原理，讨论了主要参数的设计和由于次级整流二极管的反向恢复导致主开关管的电压尖峰。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。