State-of-charge balancing control for battery energy stored quasi-Z source cascaded multilevel inverter based photovoltaic power system

The battery energy stored quasi-Z source cascaded multilevel inverter (BES-qZS-CMI) based photovoltaic power generation system combines advantages of the qZS inverter, the cascaded multilevel inverter, and the battery energy stored system. However, State of Charge (SOC) imbalance between battery modules will affect the whole system performances. This paper proposes a control method to balance the battery SOCs of all modules in the system no matter what intermittent states of PV power variations. Simulation and experimental results verify the proposed control method.