文档介绍：摘要
随着现代电力电子技术的发展,无功补偿是涉及电力电子技术、电力系统、电气自动化等领域的重要课题,也是近年来各方面关注的热点之一。本文在深入研究国内外无功补偿装置的基础上,提出了一种新型静止无功补偿装置。
补偿装置由主电路、检测电路、控制电路、驱动电路四部分组成。检测电路通过乘法和加法运算,得到实时补偿的无功功率大小。控制电路产生PWM脉冲,从而使装置实现跟踪补偿。由于补偿后的电流与电压在相位上接近,即补偿后的功率因数接近l,所以达到了动态无功功率补偿的目的。
装置在电路设计上有如下特点:主电路采用的功率开关管比以往使用的晶闸管器件在性能上有了很大的改善;检测电路是基于供电线路的瞬时电压、电流值进行瞬时无功功率的计算,方法简单、易于实现;控制电路采用PWM控制技术,在跟踪补偿电网无功功率时,产生的谐波很少。
本文对所设计装置的基本原理通过软件MATLAB进行了电路仿真。通过仿真和实验,表明该装置的基本原理和方法是可行、有效的。
关键词:无功补偿;可调电压源;PWM控制
Abstract
With the development of modern electrical and electronic technology, pensation is not only an important subject touching upon electrical and electronic technology, power system, electrical automation, etc, but also one of the focus problems in recent years. A novel static device of pensation is presented in the thesis, based on research of pensators at home and abroad.
pensation device includes 4 main parts:main circuit, measuring circuit, control circuit and drive circuit. The measuring circuit can achieve real-time reactive power to pensated by using hardware operations, such as multiplication and summation. The device can realize pensation, because PWM(Pulse Width Modulation) pulse is produced in the control circuit. The electric current and voltage are close to the phase pensating, namely the power factor is close to 1, so the purpose of dynamic pensation is achieved.
The characteristics in the circuit designed are as follows:MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) that is used in the main circuit has good improvement at performance than SCR(Silicon Controlled Rectifier) that is used in the past. Instantaneous reactive power calculated in the measuring circuit is based on instantaneous voltage and instantaneous current value of the supply power line, the calculating method is simple, easy to realize. The control circuit has adopted PWM controlling technology. The technology can product less harmonic while pensation reactive power of work.
The basic principle of the designed device circuit