Nonlinear varying-network magnetic circuit analysis for doubly salient permanent-magnet motors

In this paper, a nonlinear varying-network magnetic circuit (VNMC) modeling method is developed for doubly salient permanent-magnet (DSPM) motors. The method is used to analyze the static characteristics of DSPM motors by spe cific permeance calculations, in which the interaction between the permanen t-magnet field and the armature current field, as well as magnetic saturati on, are taken into account. Two newly proposed DSPM motors (12/8-pole and 6 /4-pole) are used as examples. There is good agreement between the results of the nonlinear VNMC modeling method and finite-element analysis. Moreover , the nonlinear VNMC method offers the advantage of calculating, effectivel y and efficiently, the static characteristics of DSPM motors having differe nt dimensions, parameters, and conditions. Finally, the proposed method is verified by experimental testing of a 6/4-pole prototype.