电力系统自动化Issue(11)：166-172,7.DOI:10.7500/AEPS20140314005
基于双坐标系复合控制的模块化多电平换流器环流抑制方法
A Circulating Current Suppression Method Based on Double Coordinate Compound Control for Modular Multilevel Converters
摘要
Abstract
The modular multilevel converter (MMC) has been widely researched and applied in high-voltage direct-current (HVDC) transmission.MMC three-phase bridge arm energy imbalance is caused by power fluctuations in the three-phase unbalanced alternating current(AC) grid,which generates internal circulating current.In light of the three-phase unbalanced DC transmission system,the internal circulating current mechanism of MMC is derived and analyzed.According to the characteristics of internal circulating current,a compound control method combining proportional-integral (PI) control and repetitive control is proposed for circulating current suppression based on positive and negative sequence in a double synchronous rotating coordinate system.This method is suitable for both three-phase balanced and three-phase unbalanced systems.Meanwhile,in order to improve the waveform quality of the direct current(DC)transmission system under the three-phase unbalanced condition,the negative sequence current compensation method based on dq decoupling control is introduced. The simulation results have verified that no matter whether the AC system three phases are balanced or not,the control strategy always has good performance in circulating current suppression,while ensuring the balance of the system”s three-phase AC. This work is supported by the State Key Program of National Natural Science Foundation of China(No.5 1237002).关键词
模块化多电平换流器/直流输电/三相不平衡/环流抑制Key words
modular multilevel converter (MMC)/direct current (DC) transmission/three-phase unbalanced/circulating current suppression引用本文复制引用
武健,刘瑜超,徐修林,徐殿国..基于双坐标系复合控制的模块化多电平换流器环流抑制方法[J].电力系统自动化,2015,(11):166-172,7.基金项目
国家自然科学基金重点项目(51237002)。 （51237002）
