不平衡负载下逆变器并联系统电能质量治理  

Power Quality Improve Strategy of Inverter Parallel System Under Unbalanced Load

作　　者：申小玲 郭昌海 SHEN Xiaoling;GUO Changhai(College of Mechanical,Electrical and Energy Engineering,Guizhou Radio&TV University(Guizhou Vocational Technology Institute),Guiyang 550023,Guizhou,China;Guizhou Survey and Design Research Institute for Water Resources and Hydropower Co.,Ltd.,Guiyang 550023,Guizhou,China)

机构地区：[1]贵州广播电视大学(贵州职业技术学院)机电与能源工程学院,贵州贵阳550023 [2]贵州省水利水电勘测设计研究院有限公司,贵州贵阳550023

出　　处：《电气传动》2021年第15期25-30,共6页Electric Drive

基　　金：贵州广播电视大学(贵州职业技术学院)校级课题(2018YB04)。

摘　　要：针对多逆变器并联系统输出侧电压不平衡的问题,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抑制策略,旨在提升电压质量。首先对逆变器输出电压进行分析,得出负载电流中的负序分量是导致逆变器输出电压三相不对称的原因,进而提出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,其中负载电流中的全部负序分量由从逆变器承担,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,避免了增加额外的电能质量治理装置。最后,基于PSCAD仿真和实验对所提控制算法的有效性进行了验证。Aiming at the problem of unbalanced output voltage of multi-inverter parallel system,a novel output stage voltage quality compensation strategy based on master-slave control was proposed.The output voltage of the inverter was analyzed,and the cause of the three-phase asymmetry of the inverter output voltage was caused by unbalanced load,the positive and negative sequence components in the load current were extracted by the method of fundamental rotation coordinate transformation,the remaining available capacity of the slave inverter was used to compensate the negative sequence component of the load current,while the main inverter only provided the fundamental component of the load current and maintained 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 reduce the imbalance of the output voltage and avoide adding additional power quality management devices.Finally,a parallel inverter simulation model was built in PSCAD environment to verify the effectiveness of the proposed control strategy.

关 键 词：多逆变器并联系统 非对称负载 电压不平衡 主从控制 

分 类 号：TM727[电气工程—电力系统及自动化]