COMPUTATION OF HYSTERESIS MOTOR-PERFORMANCE INCLUDING NEGATIVE SEQUENCE EXCITATION

Torque/slip characteristics for a hysteresis motor with a cobalt-steel rotor are computer using a multilayer electrical circuit concentrated -parameter analogue to represent the electromagnetic field equations. Hysteresis in the material is represented using a digital simulation t echnique together with an empirical method for the inclusion of the ro tational hysteresis component. Reverse acting torques due to the backw ard rotating fields produced by negative phase sequence excitation are examined. It is shown that the forward torque is altered by the backw ard rotating field owing to the nonlinearity of the rotor material.