首页|Coordinated Control of Parallel Three-phase Four-wire Converters in Autonomous AC Microgrids
Coordinated Control of Parallel Three-phase Four-wire Converters in Autonomous AC Microgrids
扫码查看
点击上方二维码区域,可以放大扫码查看
原文链接
维普
万方数据
The coordinated control of parallel three-phase four-wire converters in autonomous AC microgrids is investigated in this paper.First,based on droop control,virtual impedance is inserted in positive-,negative-and zero-sequences to enhance system damping and imbalance power sharing.Then,to fa-cilitate virtual impedance design,small signal models of the three-sequence equivalent circuits are established respectively.Corresponding indexes are proposed to comprehensively evaluate the impact of sequence virtual impedance on current sharing accuracy,voltage quality at the point of common coupling(PCC)and system stability.In addition,constraint of DC-link voltage is also considered to avoid over modulation when subjected to unbalanced loads.Furthermore,to address the PCC voltage degradation resulting from virtual impedance,a voltage imbalance compensation method,based on low-bandwidth com-munication,is proposed.Finally,simulation and experimental results are provided to verify the correctness of the theory model,indicating that the proposed method can achieve PCC voltage restoration while guaranteeing the current sharing accuracy with desirable dynamics.
AC microgridssequence virtual impedancethree-phase four-wire(3P4W)convertervoltage imbalance compensation
Rui Liu、Li Guo、Xialin Li
展开 >
Key Laboratory of Smart Grid of Ministry of Education,Tianjin University,Tianjin 300072,China