Dual active bridge and matrix converter based three-port converter topology for grid interactive PV-battery system

The integration of battery storage with solar PV is technically attractive and can solve intermittency and voltage problems. From the economic perspective, it may allow a consumer to shift their PV generation to satisfy their household loads. The addition of a battery to a home solar system requires an additional power converter. The conventional approach for the interconnection of PV-battery systems uses at least two separate power converters that results in multistage power conversion for some power flows. This paper develops an isolated bidirectional single phase three-port converter (IBSP-TPC) based on the dual active bridge (DAB) and a matrix converter (MC) for grid interactive renewable power systems that integrates distributed PV generation and battery with the load/grid. This topology considers all possible power flows depending on PV generation, battery charging power and load/grid power requirements. This also provides galvanic isolation between the three ports and ensures single stage power conversion between any two of the three ports. In addition, all switches in the DAB converters (port 1 and port 2) turn on with zero voltage switching (ZVS) which is required for reducing device switching losses, switch stress and electromagnetic interference. The operation of the IBSP-TPC is confirmed by simulation results.