A Rapid Non-Linear Computation Model of Power Loss and Electro Thermal Behaviour of Three-Phase Inverters in EV Drivetrains

This paper proposes an analytical and dynamic electro-thermal model of a three-phase inverter based on wide bandgap semiconductors (SiC) for application in electric vehicles (EV). The optimal design approach of the passive filters is presented for LCL filters at DC side and LC filters at AC side of the inverter. The analytical modelling is performed, which includes mathematical representation of the inverter's power losses based on the specifications of the datasheet of the power modules. The dynamic electro-thermal simulation model of the inverter with integrated power loss model is developed. The designed state-space system thermal model is incorporated and can be used as a virtual sensor, for the conversion of power losses to temperature. With this inverter model, it's possible to simulate designs for achieving high efficiency in a specific operating range of temperature, with high specific power and reduced cost and size. The proposed design is considered for a power load of 20kW.