A novel control strategy of the seamless transitions between grid-connected and islanding operation modes for the multiple complementary power microgrid

Abstract

ABSTRACT Micro-grid needs to integrate islanding operation mode and grid-connected operation mode together. Smooth switching between islanding operation mode and grid-connected operation mode is the key to ensure stable operation of micro-grid. In order to solve the problem of transient electrical quantity mutation in the process of dual-mode switching in microgrid, a dual-mode combined seamless switching control strategy based on current tracking is proposed for the battery inverter of the main control unit in this paper, to make the reference current of the input current inner loop controller can follow the current state at the moment before the switching moment, and maintain the correct initial value, so that the microgrid can switch smoothly and stably between grid-connected state and islanding state. Simulation results are provided to verify the effectiveness of proposed control strategy, by Power Systems Computer-Aided Design/Electro Magnetic Transient in DC System (PSCAD/EMTDC) simulation software.