UNIFIED THEORY OF TORQUE PRODUCTION IN SWITCHED RELUCTANCE AND SYNCHRONOUS RELUCTANCE MOTORS

A method is described for calculating the average and instantaneous to rque of the synchronous reluctance motor from a knowledge of the traje ctory of the phase flux-linkage versus phase current [i-psi] waveform, i.e., the same method as used with the switched reluctance motor, Thi s allows a direct comparison between torque production in the two moto rs to be made, Analytical and finite-element analysis both show that t he [i-psi] loci of the synchronous reluctance motor are ellipsoidal in shape and are not limited to the first and third quadrants as in the switched reluctance motor, The [i-psi] loci of the synchronous relucta nce motor are not bounded by the magnetization curves in the same sens e as in the switched reluctance motor and rely upon mutual coupling be tween phases for correct operation.