A Compact 50-kW Traction Inverter Design Using Off-the-Shelf Components

The requirements on volumetric density of power electronic converters in electric vehicles are increasing, since more space is needed for electronic systems and passenger capacity. The U.S. Department of Energy (DOE) has set the 2020 target for vehicular power electronic systems as 13.4 kW/l. Achieving high power density using commercial off-the-shelf (COTS) parts is challenging because these components have various form factors leading to unused spaces, as well as cooling and airflow issues. In this work, a high-power-density traction inverter, rated at 50-kW with the peak power at 74-kW, is designed and built using all COTS components. The system is tested under resistive-inductive loads and a dynamometer-based driving schedule. A power density of 13.64 kW/l was accomplished and possibilities for volume reduction to achieve 25 kW/l are evaluated revealing the challenges to achieve even higher power densities using COTS technologies.