Multi‐objective optimisation design of two‐phase excitation switched reluctance motor for electric vehicles

Abstract

Compared with the single-phase excitation mode of the switched reluctance motor (SRM), the statictorque curves of the SRM with two-phase excitation mode are more flexuous andwide flat regions are absent from the curves. To improve the static torqueperformance of the SRM with two-phase mode, geometrical multi-objectiveoptimisation strategy is developed in this paper. Considering the requirementsof the electric vehicles, four indicators are presented and defined to evaluatethe development of the SRM. Six main independent variables are determined and anovel multi-objective optimisation function was proposed to simultaneouslyimprove static performance of the SRM. Furthermore, to simplify theoptimisation, a sensitivity index that reflects the relative importance of eachvariable is developed to eliminate insignificant variables. The four-phase 8/6SRM with two-phase mode is optimised by means of the proposed multi-objectiveoptimisation method based on effects and sensitivity analysis of the designvariables on indicators. The static and dynamic torque performance of theoptimised SRM is evaluated and compared with those of the initial motor. Thecomparison results show that the multi-objective simultaneous optimisationstrategy can improve the static average torque, static average torque per mass,and global index by 18.09, 12.08, and 6.57%,respectively.