Loss Analysis of NPC and T-Type Three-Level Converter for Si, SiC, and GaN based Devices

Multilevel converters are widely used for its significant benefit of low harmonics and reduced switching losses compared to two-level converter. This paper presents a comparative evaluation of loss of two three-level inverter topologies, namely Neutral Point Clamped Converter (NPC) and T-type converter. The loss analysis are done for both topologies based on different devices like Silicon (Si), Silicon Carbide (SiC) and Gallium Nitride (GaN). Loss breakdown analysis for each switches and diodes in both topology are presented for different switching frequency and loading condition. Evaluation is mainly done with the help of MATLAB, and LTSpice. Comparison of losses for different switching frequency for different switches are done for both topologies. The result of loss estimation obtained from simulation and m-file is approximately the same. The result shows that GaN and SiC based converter is more efficient than Si based NPC and T-Type converter.