多逆变器并联系统输出电压不平衡度补偿策略  

A Strategy of Voltage Unbalance Degree Compensation Strategy of Multi-inverter Parallel System

作　　者：张冶 蔡颖凯 曹世龙 刘鑫 ZHANG Ye;CAI Ying-kai;CAO Shi-long;LIU Xin(State Grid Liaoning Electric Power Co.,Ltd.,Shenyang 110000,China)

机构地区：[1]国网辽宁省电力有限公司,辽宁沈阳110000

出　　处：《电力电子技术》2021年第6期95-98,103,共5页Power Electronics

摘　　要：为解决多逆变器并联系统输出级电压出现三相不对称的问题,在此提出一种基于主从控制的多逆变器并联系统输出级电压不平衡度改善策略。首先分析非对称负载导致多逆变器并联系统输出级电压出现三相不对称的原因,进而采用基波旋转坐标变换的方法将负载电流中的正负序分量分离出来,利用其余从逆变器可用容量来补偿负载电流中的全部负序分量,而主逆变器仅提供负载电流中的基波分量,并维持逆变器输出端电压稳定。所提控制策略将电能质量治理功能嵌入到从逆变器控制策略中,有效降低了输出端电压的不平衡度。最后,基于PSCAD仿真对所提控制算法的有效性进行了验证。In order to solve the problem of unbalanced output voltage of multi-inverter parallel system,a novel output stage voltage quality compensation strategy based on master-slave control is proposed.Firstly,based on the analysis of the mechanism of voltage unbalance in the output stage of multi-inverter parallel system caused by unbalanced load,the positive and negative sequence components in the load current are extracted by the method of fundamental rotation coordinate transformation,the remaining available capacity of the slave inverter is used to compensate the negative sequence component of the load current,while the main inverter only provides the fundamental component of the load current and maintains the stability of the output voltage of the inverter.The proposed control strategy embeds the power quality control function into the control strategy of the slave inverter,effectively reducing the imbalance of the output voltage.Finally,a parallel inverter simulation model is built in PSCAD environment to verify the effectiveness of the proposed control strategy.

关 键 词：多逆变器并联系统 电压不平衡 主从控制 

分 类 号：TM464[电气工程—电器]