Three-level inverter with 60 A, 4.5 kV Si IGBT/SiC JBS power modules for marine applications

Semiconductor modules with medium-voltage (MV) Si IGBTs and anti-parallel silicon-carbide (SiC) junction-barrier Schottky (JBS) diodes are of interest in commercial and naval converters as they allow for significantly reduced switching losses and at present are more cost-effective than an all-SiC switch. A three-level converter is being built and tested using custom modules made with 60A (120A pulsed), 4.5kV Si IGBTs and SiC JBS diodes. This work provides a platform to de-risk and evaluate the integration of SiC JBS diodes at MV using commercial modulation strategies and gating electronics with standard industry topologies for a range of switching frequencies. A comparison of SiC JBS diodes for MV, such as the decrease in turn-on IGBT losses and the elimination of snappy or avalanche recoveries is reviewed, and ways to make SiC more cost effective via topology and packaging choices are discussed.