Importance of winding and permeance harmonics in the prediction of reluctance-motor performance

Extending earlier analyses by Lawrenson and Gupta on single-speed machines and by Lawrenson, Gupta and Vamaraju on multispeed machines, generalised performance equations for single-and multispeed operation of reluctance machines are given, and their validity is supported by experimental results. The equations are used to investigate the effects of permeance and m.m.f. harmonics on machine performance, and both are shown to be of considerable practical significance. For accurate computation, it is found necessary to consider at least 40 permeance harmonics with a segmented rotor and at least 80 m.m.f. harmonics for multispeed operation of both salient-pole and segmented machines.