Photovoltaic inverter employing auxiliary circuit to synthesize multilevel output voltage

It presents a circuit configuration, which can synthesize a multilevel output voltage for the use of stand-alone photovoltaic inverter. The proposed system consists of a buck-boost converter, an auxiliary circuit, and an H-bridge inverter. The simple auxiliary circuit, which generates a multilevel output voltage, configures a switch, three diodes, and two batteries. Thanks to the multilevel output voltage, it can reduce dv/dt stress, switching loss, and output filter size. After theoretical analysis, computer-aided simulation and experimental results carries out to verify the validity of the proposed approach.