Inertial Response Improvement Method for Bidirectional Power Converter in Hybrid AC/DC Microgrid

Hybrid AC/DC microgrid has drawn wide attention recently for its expansibility and flexibility. The hybrid microgrid is a low inertia system due to the high proportion of distributed generators connected. Hence, the fluctuations of DC voltage and AC frequency in dynamic state become noteworthy issues. This paper proposed an inertial response improvement strategy for the bidirectional power converter (BPC) which contains two stages of converters and a built-in capacitor. The DC/DC converter of BPC can improve the DC subgrid inertial response by regulating the built-in capacitor of BPC. And the DC/AC converter of BPC will operate as virtual synchronous generator (VSG) and exhibit similar frequency dynamic response. The simulation result in MATLAB/Simulink is proposed to verify the proposed method.