Microgrid Power Distribution Strategy Based on Improved Control Strategy of Virtual Synchronous Generator

doi:10.12204/j.issn.1000-7229.2020.07.006

Abstract

Abstract: In a low-voltage microgrid， the virtual synchronous generator （VSG） strategy is adopted to control the parallel operation of multiple inverters. Due to the difference in line impedance， the accurate allocation of output power according to capacity cannot be realized. In view of this problem， this paper proposes an improved VSG control strategy， in which feedback and integration of voltage of common coupling point are introduced into the reactive voltage control loop to eliminate the influence of line impedance on reactive power distribution. The reactive power feedback is introduced into the virtual impedance loop to adjust the resistance value of the virtual impedance in real time according to the operation of the system. The simulation which results in Matlab/Simulink show that， the improved control strategy can realize the accurate distribution of active and reactive power， also can reduce the amplitude drop of inverter output voltage， and has strong robustness.

Key words: virtual synchronous generator（VSG）, parallel inverter, power sharing, reactive power voltage control, adaptive virtual impedance

CLC Number:

TM 341

ZHAO Jinxin， MIAO Hong， ZENG Chengbi. Microgrid Power Distribution Strategy Based on Improved Control Strategy of Virtual Synchronous Generator[J]. Electric Power Construction, doi: 10.12204/j.issn.1000-7229.2020.07.006.

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