Parameterization of transient thermal models for permanent magnet synchronous machines exclusively based on measurements

Optimizing torque and power density in electric vehicle drives, under consideration of real driving cycles and given demands for lifetime and reliability, requires the use of tools which are able to predict electromagnetic as well as transient thermal behavior. Particular difficulties in parameterizing models arise from the fact that major thermal model parameters, as for example the thermal resistance between winding and core, can be identified by experiments only, since they strongly depend on the particularities of the manufacturing process. Sometimes it is even necessary to evaluate the performance of a motor without any knowledge of its geometry. This paper introduces a new method exclusively based on measurements in order to parameterize a transient thermal model of a permanent magnet synchronous machine with a water cooling jacket. Furthermore, the related model accuracy is discussed.