Performance Comparison of Wide Band Gap Semiconductors Based Multilevel Converters for Grid Application

In recent years, Wide Band Gap(WBG) semiconductors have generated interest among both researchers and industry in the field of power electronics. The superior characteristics of WBG, such as lower channel resistance in SiC MOSFETs and low gate capacitance in GaN HEMTs, result in higher efficiency for converters equipped with these semiconductor technologies compared to converters equipped with silicon IGBTs. Conversely, multilevel converters allow the DC bus voltage to be distributed evenly between the semiconductors. This has the advantage of reducing the blocking voltage, reducing switching losses. Consequently, multilevel topologies enable the incorporation of semiconductors with blocking voltages of 650 or 1200V, particularly beneficial in applications within power systems or electric traction, where voltages occasionally exceed 2kV while maintaining high efficiency. This study aims to scrutinize and compare the performance of multilevel converters employing Si IGBT, SiC MOSFET, and GaN HEMT in scenarios where DC sources are linked to the grid, such as in solar power plants or energy storage systems(ESS).