Comparative Study of Three Stator Cooling Jackets for Electric Machine of Mild Hybrid Vehicle

Three stator cooling jacket concepts, including a new cooling jacket concept with parallel straight spiral channels, are evaluated for electric machine of mild hybrid electric car. Steady-state cooling jacket thermal flow analysis and transient-state full motor simulations with circumferential, axial, and spiral jacket concepts are carried out to predict their heat transfer performance and temperature distribution. A prototype motor has been made with the new jacket concept. Infrared thermography is performed to detect the transient temperature distribution of the motor stator windings and laminations for validation of the thermal flow analysis.