一种低谐波和零电流关断换流器运行特性的研究

Research on Operation Performance of Low Harmonic and Zero Current Switching Converter

为了解决高压大功率换流器谐波含量高、功率因数低和零电流关断(zero current switching,ZCS)问题,文中以7电平电流重注入换流器(seven level current reinjection current source converter,SLCR-CSC)为对象,研究其电流控制特性。通过分析多绕组变压器磁化电流合成原理,构建了重注入变压器电流合成数学模型,给出电流重注入变压器和功率器件的选型依据,以及重注入电流通路控制原理。MATLAB/Simulink仿真结果表明其在谐波消除的同时,实现电流过零关断和单位功率因数运行。设计1 MW物理实验平台,实验结果与理论仿真基本一致。

For solving the problems of high harmonic content,low power factor and zero current switching(ZCS)in high voltage and high power converters,the current controlled characteristics of the converter is researched with the SLCR-CSC as the object in this paper.The mathematical model of current synthesis for reinjection transofrmer is constructed,the selection basis of reinjection transformer and power device as well as reinjection current control principle are given by way of analyzing the magnetizing current synthetic principle of multi-winding transofrmer.The MATLAB/Simulink simulation result shows when it is at the time of harmonic elimination,both current zero switching and unit power factor operation are achieved at the same time.The 1 MW physical experimental platform is designed and the experimental result and the theoretical simulation are basically identical.