An Effective Cooling Scheme Using Micro Heat Pipe Array for Electrical Machines With Distributed Windings

Effective cooling can improve motor performance significantly, providing opportunities for developing high-performance motors. This article introduces a new cooling scheme using micro heat pipe arrays (MHPAs), a gravity-dependent phase change material, to augment the heat dissipation capability of the distributed winding motor. An equivalent thermal model of MHPA is established and tested to clarify its thermal performance in practical applications. An end-winding cooling structure is proposed. The relationship between structural parameters and the cooling effect is studied quantitively. Two prototypes with and without using the cooling structures were tested under various conditions. The simulation and test results show that the winding temperature can be reduced by over 35 degrees C under the rated condition, showing that the proposed cooling scheme can effectively enhance the motor's output capability.