Research on Smooth Switching Control Technology between Grid-Connected Operation and Off-Grid Operation of Micro-Grid

With the development of new energy power generation technologies, distributed wind power generation, distributed photovoltaic power generation and other power generation technologies are also making continuous progress, which can not only meet the demand for electric energy, but also solve the increasingly prominent problems of environmental pollution, so more and more attention from experts and scholars at home and abroad. As the basic component of micro-grid, distributed power supply will have a certain impact on large power grid and affect its stable operation when switching between grid-connected operation and isolated island operation. Based on the stable operation of the micro-grid, this paper systematically introduces the micro-grid structure, operation control strategy, distributed power control method and other key technologies. Starting from the distributed power control structure, the method of introducing feedback compensation and setting output power reference value is proposed to reduce the system impact in the grid-connected operation and isolated island operation, so as to achieve smooth switching effect. Finally, the effectiveness of the method is verified by simulation.