Power Management and Control Strategy for Hybrid AC/DC Microgrids in Autonomous Operation Mode

摘要

The hybrid AC/DC microgrid structure is considered to be the future trend of power systems, due to the vital necessity of connecting more renewable energy sources and storage elements to supply modern AC and DC loads. This paper proposes a power sharing and control strategy for hybrid AC/DC microgrids using the droop control technique. A new structure of the hybrid microgrid is suggested by connecting different AC, and DC sub-grids by an interlinking converter. This can be symbolized by a bi-directional converter that acts as a rectifier when power flows from the AC sub-grid to the DC subgrid. And operates as an inverter when power flows from the DC subgrid to the AC one. The proposed structure and power management strategy also allow power flows between DC sides of the system through the AC subgrid as a common bus. Five scenarios of transferring power from one sub-grid to another are studied using. MATLAB/Simulink. The results indicate a high level of the system's felexibility in managing th power flow.