Unbalanced voltage control of virtual synchronous generator in isolated micro-grid

[摘要] Virtual synchronous generator (VSG) control is recommended to stabilize the voltage and frequency in isolated micro-grid. However, common VSG control is challenged by widely used unbalance loads, and the linked unbalance voltage problem worsens the power quality of the micro-grid. In this paper, the mathematical model of VSG was presented. Based on the analysis of positive- and negative-sequence equivalent circuit of VSG, an approach was proposed to eliminate the negative-sequence voltage of VSG with unbalance loads. Delay cancellation method and PI controller were utilized to identify and suppress the negative-sequence voltages. Simulation results verify the feasibility of proposed control strategy.

[发布机构] School of Electrical Engineering and Automation, Hefei University of Technology, Hefei, China^1

[效力级别] 机械制造 [学科分类] 航空航天科学

[关键词] Control strategies;Micro grid;Negative sequence;Negative sequence voltage;PI Controller;Unbalance load;Unbalanced voltages;Voltage problems