并联T型三电平储能变流器零序环流抑制  

Zero-sequence Circulating Current Reduction for Parallel T-type Three-level Power Converter Systems

作　　者：陈刚 蒋顺平[2] 丁勇[2] 李旭[2] 石祥建[2] 刘为群[2] 

机构地区：[1]国网江苏省电力公司徐州供电公司,江苏徐州221003 [2]南京南瑞继保电气有限公司,江苏南京211102

出　　处：《电力工程技术》2017年第5期52-58,共7页Electric Power Engineering Technology

基　　金：国网江苏省电力公司科技项目"柔直和光储混联系统在城市配网中的应用"(J2017086)

摘　　要：针对共享交、直流母线的T型三电平储能变流器并联系统零序环流问题,建立并联T型三电平储能系统零序环流等效模型,并根据激励源的不同,把零序环流分为通态零序环流、开关零序环流、混合零序环流3类。首先采用一种共享直流中点方案抑制通态零序环流,其次通过一种改进型LCL滤波器方案抑制开关零序环流和混合零序环流中的高频分量,然后提出一种基于比例谐振控制的零序调制波叠加控制方案抑制开关零序环流和混合零序环流中的低频分量,最后搭建500 k W的T型三电平储能变流器并联仿真系统。仿真结果证明了文中提出的零序环流抑制策略的正确性。According to the problems about zero-sequence circulating current existed in parallel T-type three-level power converter systems, the equivalent model of zero-sequence circulating current was proposed in this paper. The zero-sequence circulating current was divided into three types according to different exciting sources, namely, conduction zero-sequence circulating current, switching zero-sequence circulating current, hybrid zero-sequence circulating current. Firstly, a scheme sharing neutral buses was proposed to reduce the conduction zero-sequence circulating current. Secondly, a parallel scheme based on improved LCL filter was proposed to reduce high frequency component of switching and hybrid zero-sequence circulating current. And a zero-sequence modulation control method based on proportion resonant controller was used to reduce low frequency component of switching and hybrid zero-sequence circulating current. Finally, parallel T-type three-level power converter systems rated 500 kW were build. Simulation results verify the correctness of reduction methods of zero-sequence circulating current.

关 键 词：T型三电平 并联 储能变流器 零序环流 比例谐振控制 

分 类 号：TM46[电气工程—电器]