Analysis and Design of SPM Machines With Fractional Slot Concentrated Windings for a Given Constant Power Region

This paper presents a novel analysis and a design method of surface-mounted permanent magnet (SPM) machines with fractional slot concentrated windings (FSCWs) for a given constant power region ratio. The characteristics of working points in the constant power region are analyzed, and a method of quantifying important parameters, magnet flux, and synchronous inductance is proposed. According to the analysis, the design method of SPM machines with the FSCWs and notes is provided. Based on the proposed method, a double-layer 20-pole/24-slot SPM machine is taken as an example and designed. The designed machine is analyzed by the finite element method (FEM), and the constant power experiment is carried out on the prototype manufactured as design. The results validate the analysis and the design method in this paper.