Physical Modeling and Analysis of Gate Drive DC-DC Converter Impact on Photovoltaic Inverter Efficiency

This paper presents results of the physical modeling and experimental investigations of the photovoltaic system based on full-SiC quasi-z-source inverter. The goal of the current research is to analyze the impact of the gate drive DC-DC converters on the photovoltaic inverter efficiency change based on experimental measurements. There are different modulation indices and different shoot-through duty cycle values applied within inverter performance analysis. It was obtained that inverter demonstrates over 97% peak efficiency in significant power range within the nominal range of operation. At the same time, the voltage level of the gate drive DC-DC converter increased from 15 to 20 V. It makes a notable impact on the efficiency of the inverter power stage in certain points within the high-efficiency power range. The total power consumption by gate drivers increased by few watts and remains relatively constant in the whole operation range of the system. Due to the proven high efficiency, the investigated solution is feasible for photovoltaic applications.