摘要
模块化多电平变换器(MMC)是一种适用于海上风电机组变流器的多电平拓扑,但其在低频工况下表现出子模块电容电压波动较大的特性,使输出电压产生畸变,影响开关器件和电容的安全工作范围。在传统高频注入控制方法的基础上,以将子模块电容电压波动限制到一定范围为优化目标,提出注入环流的幅值计算方法,改进原有控制策略,并设计了相应的子模块电容选型方案。该方法在保证子模块电容电压平稳的同时,有效降低了环流幅值,减少系统损耗。最后通过仿真和实验验证了所提控制方法的正确性。
Modular multilevel converter(MMC)is a multilevel topology suitable for offshore wind turbine converters.However,under low frequency conditions,the sub-module capacitance's voltage fluctuates greatly,which distorts the output voltage and affects the safe working range of switching devices and capacitors.Based on the traditional high-fre quency injection control method,an improved high-frequency injection control method is proposed,whose optimization goal is to limit the capacitance voltage fluctuation of the sub module to a certain range.The dimensioning of sub module capacitor is also discussed.As a result,this effectively reduces the circulating current amplitude and system loss.The proposed control method is verified by simulation and experiment.
作者
李欣
姚钢
周荔丹
LI Xin;YAO Gang;ZHOU Li-dan(Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《电力电子技术》
CSCD
北大核心
2019年第7期102-106,共5页
Power Electronics
基金
上海市自然科学基金(18ZR1418400)~~
关键词
风电变流器
低频控制
子模块电容电压
wind power converter
low frequency control
capacitor voltage of sub module
