Application of an integrated transformerless buck-boost converter in photovoltaic MPPT systems

A new photovoltaic MPPT system has been developed using an integrated transformerless Buck-Boost power converter to improve the efficiency. The paper describes the analysis, modeling and control of the Buck-boost power inverter. The transformerless Buck-boost power inverter includes a superboost converter and a buck converter though a variable mode controller to optimize the PV energy extraction. Finally, experiment research is proceeded to the MPPT system with battery chargers and DC load. Experiment results show that output power increases obviously under different solar radiation.