Improvement of reactive power dynamic response for virtual synchronous generator

Abstract

Virtual synchronous generator (VSG) control strategy has been proposed in previous papers to make distributed generations based on power electronic converters mimic synchronous generator characteristics to provide voltage and frequency support to the gird. The interaction between active and reactive power exists in VSG control strategy, which aggravates the power oscillations when utilized in distribution networks. Consequently, the rapid reactive power tracking ability of the converters will be deteriorated by the slow variation of active power. In this paper, a novel correction method is proposed to make the inverter based on VSG control achieve rapid reactive power control by decoupling reactive power from active power. Moreover, the proposed method can also suppress the power oscillation and current overshoot. The effectiveness of the proposed correction method is verified by simulations.