Analytical method for estimating electromagnetic damping in a multistator stepping motor

An analytical method is developed for predicting the electromagnetic damping of the single-step response of a multistator, variable-reluctance stepping motor operating with multiphase excitation. The analysis, which is based on the essentially sinusoidal variation of the time dependent quantities, takes into account the inherent magnetic nonlinearity. The prediction is made from relatively straightforward static tests at the machine terminals. The analytical results are compared with those obtained from experiment, and from numerical solution of the nonlinear differential equations, for a 5-phase multistator motor.