Weight reduction design of in-wheel type motor for power density improvement

This paper deals with the weight reduction design of In-Wheel type motor for high power density. Accordingly, characteristic and weight of the motor caused by modifying reduction gear ratio are examined. Weight of motor is minimized by modulating the ratio of stack length and external diameter of stator. Then, In-Wheel motor geometry based on the prototype is optimized to get the determined parameters using response surface methodology (RSM) and Finite Element Method (FEM). Optimal design of core usage in rotor is conducted for minimizing weight of motor which has identical characteristic to the prototype. Characteristic analysis is conducted by using equivalent circuit analysis of PM type motor. Through the presented weight of In-Wheel type motor, total weight is reduced to 25%, and power density is improved to 57% from the prototype motor.