Holistic Thermal Management System Design, Testing, and Modeling for 300 kW IGBT-Based Inverter for Switched Reluctance Motor Drives

The thermal management system of inverters became a bottleneck challenge for advances in motor drive design of electric vehicles concerning the power density and the rated power that can be achieved without exceeding the maximum operating junction temperature of power modules of inverter. This paper aims to propose a thermal management system design for IGBT-based power modules used for 300 kW traction inverters used specifically for switched reluctance motor drives. Hence, an innovative cold plate design was adapted by using diamond-shaped pin-fin heat sinks. The diamond-shaped pin-fin configuration allows a promising thermal management system performance, characterized by safe operational junction temperature of the IGBTs below 150 °C at relatively high heat losses, accompanied by low-pressure drop. A Foster thermal network model was constructed in this work which can predict the junction temperature of the IGBTs transiently during operation with switched reluctance motors through different drive cycles. Therefore, this model allows us to perform feedback control actions to derate the inverter operation during unsafe operational junction temperature conditions for an extended lifetime for the inverter power modules.