Evaluation of three cooling concepts for an electric vehicle motor - Lumped parameter models

Paper in proceeding, 2020

Three different cooling solutions for the same permanent magnet electric vehicle traction machine are compared using 2D finite element method generated loss maps and a thermal lumped parameter network. Two water jackets, with a wave and a spiral shaped channel, are compared to an end-shield cooling channel with end winding potting. The coolant convection is estimated using 3D conjugate heat transfer simulation software, presented in an accompanying paper. The continuous and overload torque capability are determined as well as the winding temperatures and energy losses during a set of low, middle and high-speed drive cycles. The results indicate very similar performance for the two water jackets. With the end-shield cooling the continuous torque is considerably higher at low speed levels, higher torque levels can be sustained for a certain time, and the drive cycle winding temperatures and losses are lower compared to the cooling jackets.