Dynamic evaluation of the overloading potential of a convection cooled permanent magnet synchronous motor

In order to obtain the maximum efficiency from a hybrid driveline it is crucial to optimize the power distribution between the electric drive and the internal combustion engine. An accurate estimation of how much electric power can be delivered at any instant of time is therefore of great interest. Such estimation is dependent on several factors, as the state of charge of the battery, the temperature and the cooling conditions of the motor and the power electronics at that particular moment. This article proposes a method for evaluating the overloading potential of the electric drive dynamically at any time, based on a previously developed thermal model. Alternative modelling techniques are discussed and the resulting thermal model is validated against experimental measurements.