Decentralised coordinated energy management for hybrid AC/DC microgrid by using fuzzy control strategy

The islanded hybrid AC/DC microgrid consisting of battery energy storage (BES) systems, photovoltaic (PV) generators, and bidirectional power converter (BPC) possesses the advantages of flexibility and extendibility. To ensure the safety and stability of operation, the power of BES and BPC needs to be restrained within their designed limits regardless of the power fluctuation in the hybrid microgrid. Besides, the over-charge and over-discharge of BES should be prohibited. In this study, a decentralised generation-storage-subgrid coordination control for power management is proposed to assure the power limitation and state of charge (SOC) protection. In the control strategy of BES, a modified droop method is adopted to deliver the storage's both SOC and output power signals without communication links. Meanwhile, a fuzzy logic controller is adopted in BPC, which can prevent the overuse of BESs in both subgrids and limit the maximum output power of BPC. In addition, a modified P&O strategy is applied in PV systems as a supplement of overuse protection. Finally, the effectiveness of the proposed control strategy is verified on RT-Lab experimental platform.