Open-loop Phase Synchronization Method of Positive and Negative Sequences for Three-phase Asymmetric Grid  

作　　者：Jian He Shanxu Duan 

机构地区：[1]State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《CSEE Journal of Power and Energy Systems》2023年第5期1973-1979,共7页中国电机工程学会电力与能源系统学报(英文)

摘　　要：Currently,a grid-connected inverter is required to inject a dual-sequence current during asymmetric grid sags,which means both positive and negative sequence phases should be tracked.This paper proposes an open-loop phase synchronization(OLS)method of positive and negative sequences for an asymmetric grid based on the moving average filter(MAF),which does not need to separate the positive and negative sequence fundamental components of grid voltage.As a benefit,there is no double-frequency oscillation in the estimated phases at offnominal frequencies since the positive and negative sequence phases are obtained simultaneously.The proposed method not only has the inherent advantages of OLS,but also further improves the dynamic response since the window length of MAF is only 1/6 of the fundamental period.The effectiveness of the proposed OLS is verified by experimental results.

关 键 词：Asymmetric grid open-loop synchronization positive and negative sequence phases 

分 类 号：TN713[电子电信—电路与系统] TM761[电气工程—电力系统及自动化]