A new buck boost interface converter with lower switching stress for photovoltaic application

Abstract

This paper proposes a power electronic interface (PEI) for photovoltaic (PV) system. This PEI is based on Neutral point clamped (NPC) inverter connected to a high step up boost converter with voltage doubler circuit to achieve higher boost capability and lower voltage stress on devices and also make neutral point for NPC inverter. Lower voltage stress on devices and its boost capability make mentioned PEI suitable for transformerless application that needs lower voltage stress on devices. Moreover a controller is presented to keep NPC capacitor voltage balanced and regulates PV voltage to its reference voltage provided in maximum power point tracking algorithm. The proposed PEI performance is verified using simulation in MATLAB/Simulink.