Assessment and Summary of Inverter and Induction Motor Efficiency in Dual Electric Vehicle Drive Systems Across Urban and Highway Driving Conditions

Recent studies have shown that battery-powered motors and power electronic inverters are crucial parts of contemporary dual electric vehicle driving systems. Consequently, the traction engine and its accompanying drive must run at peak efficiency all the way through the driving schedule. The traction motor and drive system in a hybrid electric vehicle (HEV) typically utilize the full range of torque and speed operating conditions. With this in mind, the objective of this work is to estimate the efficiencies of the inverter and motor over common urban and highway driving patterns. The significant losses within a standard three-phase DC/AC traction inverter, including switching and conduction losses in the insulated-gate bipolar transistors and antiparallel diodes, are modelled and approximated for both urban and highway driving. Using an Automobile Simulator program, a medium-sized SUV equipped with an induction motor was simulated, accounting for copper losses in the stator, rotor, and core. The average efficiencies of the inverter drive and induction traction motor are then evaluated and summarized for both urban and highway driving conditions. Finally, the overall efficiency of the traction motor drive system is assessed based on the individual component performance analyses.