电网不平衡条件下PWM整流器的并联控制方法  

Parallel connection control method for the PWM rectifiers under unbalanced power grid voltage conditions

作　　者：陈宏志[1] 王旭[1] 刘建昌[1] 

机构地区：[1]东北大学信息科学与工程学院,辽宁沈阳110004

出　　处：《电机与控制学报》2009年第5期702-707,共6页Electric Machines and Control

基　　金：教育部博士点基金(20060145025)

摘　　要：针对电网不平衡的情况下三相电压型PWM整流器易产生交流电流和直流电压谐波的问题,提出采用两组PWM整流器并联形式的解决方案。一组作为主整流器,用以产生正序电流,另一组作为辅助整流器,用以产生负序电流,同时保证主、辅整流器输出到直流侧的瞬时功率之和不含交流分量。推导正、负序电流与电网正、负序电压及直流功率的关系,并设计出控制系统。建立基于Matlab的三相电压型PWM整流器的仿真平台对三相电压型PWM整流器在电网电压不平衡时不同负载工况的条件下进行充分仿真研究。仿真结果表明,本文所提出的方法能够将三相电压型PWM整流器的谐波抑制到电网平衡条件下的水平。Under the unbalanced power grid voltage conditions, three-phase voltage source PWM rectifier would produce AC current and DC volts harmonics. To deal with this problem, a solution integrating two PWM rectifiers by parallel connection was presented. In this solution, one PWM rectifier served as main rectifier to produce positive sequence current, the other acted as assistant rectifier to produce negative sequence current. It was assured that the overall instantaneous power from the main rectifier and assistant rectifier didn＇ t contain AC current elements at DC side. In addition, the relations among the positive and negative sequence current, the positive and negative sequence voltage of the power grid, and the power of DC load were deduced and the corresponding control system was developed. Finally, a Matlab based simulation platform for three-phase voltage source rectifier（VSR） was designed. Moreover, a lot of simulation experiments were conducted under the unbalanced network voltage conditions and different loads conditions. Simulation experiments demonstrate that the proposed method could suppress the level of harmonics of three-phase VSR to the level under the balanced network voltage conditions.

关 键 词：整流器 谐波抑制 并联系统 电压不平衡 

分 类 号：TM461[电气工程—电器]