级联型STATCOM不平衡故障穿越负序电流抑制  

Negative-sequence Current Suppression Method for STATCOM in Power Grid Fault Ride Through

作　　者：钦伟勋 胥晶 徐勇生 王振 QIN Wei-xun;XU Jing;XU Yong-sheng;WANG Zhen(State Grid Huzhou Power Supply Company,Huzhou 313000,China;不详)

机构地区：[1]国网湖州供电公司,浙江湖州313000 [2]浙江泰仑电力集团有限责任公司配电工程分公司,浙江湖州313000

出　　处：《电力电子技术》2023年第1期23-26,共4页Power Electronics

基　　金：浙江泰仑电力集团有限责任公司科研项目(202001693)。

摘　　要：为了改善在电网不平衡故障穿越中,级联型H桥静止同步补偿器(CHB-STATCOM)输出电流对称度和谐波特性,首先建立了不平衡故障电网负序电压和STATCOM相直流侧电压的定量关系,揭示了分离直流侧电压可获得对应的交流负序电压分量机理,提出通过调节三相直流电压即可直接产生相应的交流负序电压分量,实现对输出负序电流抑制;其次,利用直流电压闭环调节进一步产生装置高调制比,以改善输出电流谐波特性,最后通过380 V/7 kVA级联型STATCOM动模原理样机验证了所提控制方法的正确性和有效性。The unbalanced grid voltages can generate negative-sequence currents for the cascaded H-bridge static synchronous compensator(CHB-STATCOM).To improve the currents quality,a new negative-sequence current limiting method by varying three clustered DC voltages is proposed.To counteract the negative sequence grid voltage,the relationship between the negative-sequence voltage and clustered DC voltage is established.This relationship reveals that the differences between three clustered DC voltages and their average voltage can generate negative-sequence voltages,which can achieve symmetric modulation waves to balance three-phase DC-link ripples,and limit the third harmonic currents.Moreover,to achieve fixed and high modulation index,a modulation index control is employed by regulating the average voltage of three clustered voltages.The advantages of the proposed method are verified in a 380 V/7 kVA cascaded STATCOM prototype.

关 键 词：静止同步补偿器 负序电流 故障穿越 

分 类 号：TN715[电子电信—电路与系统]