A Flexible Interconnection and Power Sharing Strategy For Two Autonomous Microgrid Systems

Microgrids are defined as interconnected networks of loads and distributed energy resources. A microgrid should be able to meet its own demand. However, a microgrid may be temporarily overloaded due to generation intermittency and demand fluctuation. This problem can be solved by enabling a microgrid to import power from another microgrid after a quick interconnection. This paper proposes an interconnection method for two microgrids through a static switch, along with an effective power sharing strategy to ensure power supply is not interrupted to either microgrid, based on their available generation capacity during the islanded mode. The advantage of the proposed method is that the interconnection takes place between the DC buses, so it eliminates the need to maintain frequency and therefore reduces the complexity and cost of the system. Time-domain simulations using MATLAB/Simulink are conducted to assess the performance of the proposed interconnection and power sharing strategy.