Research on Optimization of independent microgrid based on flexible interconnection technology

In order to solve the problem of interconnected operation control between different independent microgrids, a flexible interconnection method based on bidirectional AC / DC converter is used to connect the independent microgrids. Each microgrid and the AC side of the connected converter form a separate control area. The branch power flow model is adopted in the internal network of the area to optimize the photovoltaic unit, energy storage system, diesel generator unit and other equipment. The active power of the boundary of the adjacent area is coordinated and controlled by the distributed optimization algorithm based on the alternating direction multiplier method. Under normal working conditions, the coordination and complementarity of the devices in the micro grid can be realized through the flexible interconnection device, which can improve the system operation economy; under the condition of equipment failure, based on the flexible control and power support ability of the flexible interconnection device, the power outage range of the fault micro grid can be reduced. Finally, a simulation case is used to verify the effectiveness of the above methods under different operating conditions.