Analysis and Design of Low-Speed Six-Phase Fractional-Slot Concentrated-Winding PM Motor Applied to Marine Propulsion

The slot-pole coordinate constraint condition of low-speed six-phase half-symmetrical fractional-slot concentrated-winding PM motor applied to marine propulsion is analyzed, all slot-pole combinations applied to six-phase fractional-slot motor within 60 slots and 52 poles are listed. The slot-pole combination optimized selection method based on theoretical analysis is proposed. Mainly considering of increasing winding distribution factor and reducing cogging torque, a 48 slots and 44 poles six-phase fractional slot concentrated-winding PM motor with 20 kW rated power is designed. Experimental results indicate that the PM motor has good performances and the proposed method applied to the design of multi-phase fractional slot concentrated-winding PM motor is feasible.