不平衡工况下星形级联SVG的补偿分析  

Analysis on the Compensation of Star-connection Cascaded SVG in Unbalanced Conditions

作　　者：徐圣涛 张茂松[1,2] 陶骏 王群京 XU Sheng-tao;ZHANG Mao-song;TAO Jun;WANG Qun-jing(Anhui University,Hefei 230601,China)

机构地区：[1]安徽大学电气工程与自动化学院,安徽合肥230601 [2]安徽大学,工业节电与电能质量控制协同创新中心,安徽合肥230601 [3]教育部电能质量工程研究中心(安徽大学),安徽合肥230601

出　　处：《电力电子技术》2021年第3期21-25,共5页Power Electronics

摘　　要：星形级联静止无功发生器(SVG)在补偿不平衡负载时,通常采用零序电压注入法来维持直流侧相间平衡,由于相间平衡的前提是SVG输出电压需与输出电流相垂直,故其相量内积为零,则可通过待定系数法简单直接地求出所需的零序电压;在此基础上可以进一步确认星接SVG的不平衡补偿范围,SVG直流侧电压的大小对不平衡补偿范围有着重要意义;准PR控制能有效进行电流跟踪,在此提出了新型直流侧电压分层控制策略,它可有效减少负序分量对补偿性能的影响。所提策略在相关仿真和实验中得到了充分验证。When the star-cascade static var generator(SVG)compensates unbalanced load,it usually adopts the method of injecting zero-sequence voltage to maintain the interphase balance on the DC side,since the interphase balance is based on the premise that the output voltage of SVG is perpendicular to the output current,the internal product of its phasor is zero,therefore,the required zero-sequence voltage can be obtained simply and directly by the undetermined coefficient method.On this basis,the unbalance compensation range of star-connected SVG can be further confirmed,the voltage of SVG DC side is of great significance to the unbalance compensation range.Quasi-PR control can effectively carry out current tracking,a new DC side voltage hierarchical control strategy is proposed,which can effectively reduce the influence of negative sequence components on compensation performance.The above description has been fully verified in the relevant simulation and experiment.

关 键 词：静止无功发生器 不平衡工况 零序电压 补偿范围 

分 类 号：TM761[电气工程—电力系统及自动化]