6.5 kV SiC PiN and JBS Diodes’ Comparison in Hybrid and Full SiC Switch Topologies

This work investigates the performance of state-of-the-art non-commercial 6.5 kV Silicon Carbide (SiC) PiN and Junction Barrier Schottky (JBS) diodes in hybrid (Si IGBT with SiC diode) and full SiC (SiC MOSFET with SiC diode) switch topologies. The static and dynamic performance has been systematically evaluated at distinct temperatures, gate resistances and currents for each configuration. The SiC PiN diode presented higher current density capability and lower leakage current density than the JBS diode. Moreover, in most cases, the SiC PiN diode-based topologies demonstrated slightly higher total switching losses compared to the SiC JBS diode-based equivalent configurations. A loadability analysis in a three-level NPC converter is presented to evaluate the potential of each configuration in a converter application. The SiC PiN technology presented a 25% power extension compared to the SiC JBS technology with similar efficiency at typical industrial drives switching frequency operation when comparing same-active-area diode technologies. Finally, a long-term reliability test (H3TRB) is presented to demonstrate the SiC PiN diode technology’s potential for operation in harsh environments. Such characteristics show the advantage of the 6.5 kV SiC PiN diode when a high current density (>100 A/cm2), high efficiency and reliability are required.