Development and Testing of a Low Cost High Performance Hybrid Vehicle Electric Motor

A large proportion of automotive engineering research is focused on the reduction of vehicle fuel consumption thereby reducing CO₂ emissions. One effective method is to use an electric motor in conjunction with the engine (hybrid electric vehicle). This paper details the development and performance characteristics of a low cost hybrid vehicle electric motor, originally developed for the retrofit hybrid vehicle market, although it is intended to be suitable for many applications. The motor is a low cost, scalable, high performance motor, primarily for automotive applications. The motor has been designed to make it stackable for higher power or torque requirements. The use of lightweight materials and innovative cooling designs are novel to this motor. Results obtained from extensive testing of the motor are detailed in the paper including the efficiency map, power and torque curves, continuous powers, etc. The peak torque obtained was 70 Nm while the peak power output was 14.9 KW, whilst the maximum efficiency of the motor was found to be in excess of 90%. It was also seen that increasing the magnetic air gap between the stator and the rotor from 1 mm to 6 mm, decreased the peak torque values of the motor from 70 Nm to 45 Nm, but helped achieve a higher speed of 7500 rpm.