Indirect End Turn Heat Exchanger for Additively Manufactured Electric Machine Conductors

Additive manufacturing of electric machine conductors allows for new and innovative thermal management methods which can significantly improve the efficiency, specific power, lifetime and reliability of electric machines. Air cooling the conductor end turns with an integrated heat exchanger has proven it's capability to outperform conventional cooling methods, however, direct air cooling has major drawbacks as the heat exchanger must also be electrically insulated. This paper investigates the cooling capacity of an indirect air-cooled heat exchanger on the conductor end turn, which is electrically isolated. To demonstrate the design considerations for implementing either design, a comparison is made between the indirect and the direct air-cooled end turn heat exchanger, highlighting their respective advantages and challenges.