Loss models of a PMSM in an outer rotor flywheel concept

This paper describes the analytic model of a permanent magnetic synchronous machine (PMSM) of a flywheel in outer rotor design. The model is used for loss prediction within a parametric optimization algorithm. It accounts for iron and copper losses as function of electric power and rotational velocity. Magnetic state and currents are approximated by empirical assessments and an analytical model for the magnetic vector potential. A comparison of the proposed model with finite element (FE) simulations and measurements show that the fit with the FE model is already sufficient but that there are significant deviations between both models and the measurements due to the switching of the used frequency inverter.