Use of a Permeance Model to Predict Force Harmonic Components and Damper Winding Effects in Salient Pole Synchronous Machines

This paper presents a combined finite-element and analytical modeling technique for the prediction of force density harmonics in salient pole synchronous machines. The model calculates the induced currents in the damper winding cage and includes their effect on force density components in the solution. Use of a combined analytical and finite element approach considerably reduces simulation times compared to full time-stepping finite element solutions, while including the effects of design changes on airgap force harmonics. Results of the model predictions are presented together with measured data from two different machines.