Design and development of a 500kW utility-interactive switch-clamped three-level photovoltaic inverter

This paper introduces the development of a switch-clamped utility-interactive photovoltaic inverter intended for very large scale photovoltaic (PV) power generation. The switch-clamped inverter proposed is superior to the diode-clamped inverter in terms of converter losses and harmonic distortion, thus a high efficiency of 98.5% was achieved by applying a switch-clamped three level inverter and latest 6^th generation IGBTs. The adoption of a three level configuration, supported by CAD design tools made possible to achieve a considerable reduction in size. Factory test results are presented to confirm the inverter performance and suitability for large-scaled photovoltaic applications.