模块化多电平换流器子模块平均开关频率的精确控制方法  

Precision Control Method of Average Sub-module Switching Frequency for Modular Multilevel Converters

作　　者：郭裕群 赵成勇 许建中 何智鹏 傅闯 周月宾 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市102206 [2]南方电网科学研究院,广东省广州市510080

出　　处：《电力系统自动化》2016年第19期94-100,共7页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51177042);国家高技术研究发展计划(863计划)资助项目(2013AA050105)~~

摘　　要：在现有的基于电容电压排序的优化均压算法基础上,提出一种适用于模块化多电平换流器(MMC)的精确控制子模块开关频率的方法。通过引入双保持因子,避免绝缘栅双极型晶体管(IGBT)不必要的反复投切现象,从而在保证各子模块电容电压基本一致的前提下,有效地降低MMC子模块开关频率,减小开关损耗;在此基础上,设计了精确控制子模块开关频率的比例—积分(PI)控制器,能够在降低开关频率的同时精确地控制其大小,保证系统稳定运行和换流器的运行效率;最后,为证明所提出频率控制方法的有效性,在PSCAD/EMTDC中搭建了双端101电平MMC仿真模型,对所提出的方法进行了验证,仿真结果表明该方法可以在保证系统稳定运行的前提下,精确地控制子模块的开关频率,证明了所提出方法的正确性和有效性。According to the existing optimal voltage balancing algorithm based on capacitor voltage sorting,aprecision control method of sub-module switching frequency for modular multilevel converters（MMCs）is proposed.First,by introducing the double holding factors,unnecessary repeated switching of the insulated gate bipolar transistor（IGBT）is avoided and the switching frequency is significantly reduced,which decreases the switching losses of converters.Secondly,aproportionalintegral（PI）controller is proposed,which is able to accurately control the switching frequency of sub-modules while decreasing the frequency.Third,to validate the effectiveness of the proposed method,a 101-level point-to-point MMC simulation model is developed in PSCAD/EMTDC.The simulation results show that the method is able to accurately control the switching frequency of sub-modules on the premise of guaranteeing stable operation of the system,which proves the rationality and effectiveness of the proposed method.

关 键 词：模块化多电平换流器 排序均压算法 子模块开关频率 保持因子 比例—积分控制器 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM46