A single phase transformer-less string inverter with integrated magnetics and active power decoupling

This paper proposes a transformer-less single phase inverter for photovoltaic (PV) application with integrated magnetics and active power decoupling minimizing the capacitance requirement, converter volume, and cost. The topology is a combination of boost and half-bridge stages along with a buck-boost power decoupling stage. This converter ensure the complete elimination of high frequency capacitive coupled ground current by the combination of the half-bridge buck-boost stages. The inductors of these two stages are integrated in one single core to further reduce the core loss and converter volume and cost. Closed loop experimental results of the converter with integrated magnetics are provided to validate its operation.