基于改进冒泡排序的模块化多电平换流器电容电压均衡策略  

Modular multilevel converter capacitor voltage balancing strategy based on improved bubble sorting

作　　者：张婕 曾国辉[1] 赵晋斌 黄勃[1] 肖博 ZHANG Jie;ZENG Guohui;ZHAO Jinbin;HUANG Bo;XIAO Bo(School of Electronic and Electrical Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;School of Electrical Engineering,Shanghai Electric Power University,Shanghai 200090,China)

机构地区：[1]上海工程技术大学电子电气工程学院,上海201620 [2]上海电力大学电气工程学院,上海200090

出　　处：《电力系统保护与控制》2020年第6期92-99,共8页Power System Protection and Control

基　　金：国家自然科学基金项目资助(61603242);机械电子工程学科建设项目资助(2018xk-A-03)。

摘　　要：模块化多电平换流器(Modular Multilevel Converter, MMC)子模块电容电压均衡是当前MMC研究领域的热点问题。当MMC的单个桥臂子模块数量较多时,存在控制器运算时间长、子模块投切频繁和开关损耗大并导致MMC故障等缺陷。针对上述缺陷,提出了一种基于改进冒泡排序算法和平均值法混合控制策略。通过实时监测电容电压,采用改进冒泡法在初始化时对子模块电容电压进行排序,减少MMC控制器的运算量。在之后的控制周期采用已投入子模块平均值比较法对子模块作投切,降低开关频率。最后在Matlab/Simulink搭建21电平MMC模型,仿真结果验证了所提混合控制策略的有效性和正确性。Modular Multilevel Converter(MMC) sub-module capacitor voltage balancing is a hot topic in current MMC research. Large number of single bridge arm submodules in MMC usually lead to the defects such as long controller operation time, frequent switching of sub-modules, and large switching loss leading to MMC failure. To solve above problems, this paper proposes a hybrid control strategy based on improved bubble sorting algorithm and voltage average comparison. According to monitor the capacitor voltage in real time, this paper adopts the improved bubble sorting algorithm to rank the capacitor voltage of the sub-modules during system initialization which can reduce operations and simulation time of MMC controller. The sub-module voltage average comparison strategy is adopted in the subsequent control cycle to switch the sub-module which can reduce the switching frequency. Finally, the 21-level MMC model is built on Matlab/Simulink. The simulation results prove the feasibility and effectiveness of the proposed hybrid control strategy.

关 键 词：模块化多电平换流器 改进冒泡原理 电容电压均衡 开关频率 最近电平控制 平均值比较 

分 类 号：TM46[电气工程—电器]