Winding Embedded Liquid Cooling for Slotless Motors in Transportation Applications
Ritvik Chattopadhyay, Md Sariful Islam, Junyeong Jung, Rajib Mikail, Iqbal Husain
Abstract
A novel winding embedded liquid cooling (WELC) concept is presented to improve the thermal management of slotless motors for transportation applications. The concept introduces liquid cooling channels through the non-magnetic thermal plastic winding support in a slotless motor to reduce the thermal resistance between the heat source and the sink. This article demonstrates the efficacy of the WELC concept for a 11.5-kW slotless motor using computational fluid dynamics (CFD). A lumped parameter thermal network has also been developed for the WELC concept, which has been validated using the CFD analysis. The simulation results of WELC concept have been experimentally validated for an 11.5-kW slotless motor. It is shown that the WELC concept can achieve a continuous current density of 19.0 A(rms)/mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{2}$</tex-math></inline-formula> for an allowable temperature rise of 80 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{\circ }$</tex-math></inline-formula> C; the achieved continuous current density is 35% higher than that of a conventional axial in-slot water jacket cooling. The short time (18 s) peak current density achieved with the WELC concept is 39.8 A(rms)/mm <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{2}$</tex-math></inline-formula> .