电工技术学报2017，Vol.32Issue(14)：17-26,10.DOI:10.19595/j.cnki.1000-6753.tces.170592
基于能量平衡的降低模块化多电平变换器子模块电容电压波动控制策略
Control Strategy Based on the Energy Balance for Reducing Sub-Module Capacitor Voltage Fluctuation of Modular Multilevel Converter
摘要
Abstract
Capacitors are the key elements in the sub-modules of the modular multilevel converter (MMC). Reducing sub-module capacitor voltage fluctuation is a dual requirement to improve capacitor reliability and reduce converter costs. Firstly, the influence of different circulating currents to the capacitor voltage fluctuation is analyzed in this paper. It is shown that injecting the typical 2nd order circulating current can reduce the capacitor voltage fluctuation greatly without increasing too much loss. Secondly, after introducing the existing energy-balance based control strategy with the line-cycle time scale, the control strategy with the control-cycle time scale is proposed. It can reduce the capacitor voltage fluctuation by injecting the 2nd order circulating current and improve the transient performance at the same time. Compared with the traditional proportional-integral controller, the proposed energy-balance based control strategy avoids the complicated adjusting process of parameters, which can be used in various conditions. Finally, both simulation and experimental results verify the proposed control strategy.关键词
模块化多电平变换器/环流/电容电压波动/能量平衡Key words
Modular multilevel converter/circulating current/capacitor voltage fluctuation/energy balance分类
信息技术与安全科学引用本文复制引用
李凯,赵争鸣,袁立强,鲁思兆..基于能量平衡的降低模块化多电平变换器子模块电容电压波动控制策略[J].电工技术学报,2017,32(14):17-26,10.基金项目
国家自然科学基金重大项目资助(51490680,51490683). （51490680,51490683）
