Method for predicting the dynamic response of a variable-reluctance stepping motor

A method is described for predicting the index response of a reluctance-type stepping motor from the results of static tests at the machine terminals. The method involves solving the system equations by numerical integration once an equivalent circuit representing one phase of the motor has been obtained. To obtain this circuit requires (a) representation of the flux linkages of one phase as a function of current and angular position of the rotor by using a polynomial in the two variables, and (b) representation of eddy currents in the core by suitably chosen resistive circuits in parallel with sections of the coil. A comparision of experimental and predicted responses for a commercially manufactured stepping motor is presented.