基于MMC环流模型的通用环流抑制策略  

A Novel Universal Circulating Current Suppressing Strategy Based on the MMC Circulating Current Model

作　　者：杨晓峰[1] 郑琼林[1] 

机构地区：[1]北京交通大学电气工程学院,北京市海淀区100044

出　　处：《中国电机工程学报》2012年第18期59-65,178,共7页Proceedings of the CSEE

基　　金：中央高校基本科研业务费重点专项(2010JBZ009);北京交通大学优秀博士生科技创新基金(141091522)资助~~

摘　　要：模块组合多电平变换器(modular multilevel converter,MMC)的环流直接影响MMC的工作特性。该文推导了MMC环流、桥臂电流和公共直流母线电流之间的数量关系,指出环流是引起公共直流输入/输出功率存在低频脉动的原因。为实现对MMC环流的有效抑制,提出一种基于MMC环流模型的通用环流抑制(universal circulating current suppressing,UCCS)策略,实现原理简单,无需负序坐标变换和相间解耦环节,适用于任意相数的MMC控制,并进行了仿真和实验验证。结果表明,UCCS策略能显著抑制环流中的低频交流脉动分量,消除桥臂电流的畸变,同时可有效抑制公共直流输入/输出功率脉动,有利于MMC系统的稳定可靠运行。The performance of modular multilevel converters（MMC） was affected directly by the circulating current.The relation among the circulating current,the leg current and the common dc-bus current was firstly derived,which reveals that the low-order ripple components in the common dc-bus input/output power was caused by the circulating current.Then,a novel universal circulating current suppressing（UCCS） strategy based on the circulating current model was proposed for suppressing the circulating current.Without the second-order negative-sequence coordination transformation and the phase decoupling control,the UCCS strategy was simple in principle,and was suitable for an arbitrary number-phase MMC control.Both the experiment and the simulation verification were carried out,experimental results show that the UCCS strategy can not only effectively suppress the low-order ripple components in both the circulating current and the common dc-bus input/output power,but also improve the leg current distortion,which is benefit for improving the stability and reliability of MMC.

关 键 词：模块组合多电平变换器 环流 桥臂电流 环流模型 通用环流抑制策略 

分 类 号：TM46[电气工程—电器]