Cryogenic Evaluation and Modeling of a 900 V Cascode GaN HEMT

The increasing demand for more electric aircraft (MEA) to ensure zero carbon emission has spurred the research interest in cryogenic power converters integrated with deep cryogenic drive trains. Although both silicon carbide and GaN have proven to be appropriate candidates for high-temperature applications, the latter has been determined to be more suitable at cryogenic ambient since it provides relatively constant breakdown voltage, lower on-state voltage drop, and better switching time. The work in this article presents a comprehensive characterization of a 900V cascode GaN device at cryogenic temperature. The operation principle, cryo-charaeteristics, and physics-based explanation have been presented. A commercial SPICE model has also been utilized to model the cryogenic behavior. A 5-level cascaded H-bridge inverter has been simulated and loss has been calculated.