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This paper presents a comprehensive short-circuit ruggedness evaluation and numerical investigation of up-to-date commercial silicon carbide (SiC) MOSFETs. The short-circuit capability of three types of commercial 1200-V SiC MOSFETs is tested under various conditions, with case temperatures from 25 to 200 °C and dc bus voltages from 400 to 750 V. It is found that the commercial SiC MOSFETs can withstand short-circuit current for only several microseconds with a dc bus voltage of 750 V and case temperature of 200 °C. The experimental short-circuit behaviors are compared, and analyzed through numerical thermal dynamic simulation. Specifically, an electrothermal model is built to estimate the device internal temperature distribution, considering the temperature-dependent thermal properties of SiC material. Based on the temperature information, a leakage current model is derived to calculate the main leakage current components (i.e., thermal, diffusion, and avalanche generation currents). Numerical results show that the short-circuit failure mechanisms of SiC MOSFETs can be thermal generation current induced thermal runaway or high-temperature-related gate oxide damage. [ABSTRACT FROM PUBLISHER]

A Si insulated-gate bipolar transistor (IGBT) phase-leg module is developed for operating at 200 °C in hybrid electric vehicle applications utilizing the high temperature packaging technologies and appropriate thermal management. The static and switching electrical characteristics of the fabricated power module are tested at various temperatures, showing that the module can operate reliably with increased but acceptable losses at 200 °C. The criterion on thermal performance is given to prevent thermal runaway caused by fast increase of the leakage current during a high temperature operation. Afterward, the thermal management system is designed to meet the criterion, the performance of which is evaluated with experiment. Furthermore, two temperature-sensitive electrical parameters, on-state voltage drop and the switching time, are employed for thermal impedance characterization and the junction temperature measurement during converter operation, respectively. Finally, a 10-kW buck converter prototype composed of the module assembly is built and operated at the junction temperature up to 200 °C. The experimental results demonstrate the feasibility of operating Si device-based converters continuously at 200 °C. [ABSTRACT FROM AUTHOR]