Abstract：In islanded mode microgrid, circulating current among parallel inverters due to the voltage differences and disproportionate line impedances cannot be neglected. In this paper, the influence of external inductor, local load and line impedance on circulating current is taken into consideration in the equivalent feeder calculation. The equivalent feeder voltage drop is calculated and added to the reference voltage of droop control as voltage compensation. Meanwhile, adaptive virtual complex impedance is adopted to provide quick responses to load change and the mismatch of line impedances, which can reduce the resistant part of line impedance and improve the line impedance proportional accuracy. Simulation results show that the equivalent line impedance calculation method can reflect the variation of grid parameters. The proposed control strategy can suppress the circulating current well and improve the accuracy of power proportional sharing.
张明锐, 王佳莹, 宋柏慧, 韦莉. 基于等效馈线的孤岛微网并联逆变器间环流抑制策略[J]. 电气技术, 2018, 19(7): 1-8.
Zhang Mingrui, Wang Jiaying, Song Baihui, Wei Li. The circulating current suppressing strategy based on equivalent feeder for parallel inverters in islanded microgrid. Electrical Engineering, 2018, 19(7): 1-8.
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2018, Vol. 19 
