Efficiency Evaluation of New Variable Magnetic Flux Motor: DEVELOPMENT OF EV MOTOR WITH WIDE RANGE HIGH-EFFICIENCY DRIVE

To achieve wide range high-efficiency drive of EV motor, the new structure of VMFM is proposed. To confirm the effect on efficiency for wide range drive, comparatively small prototype motor was experimentally manufactured and evaluated. It is found that the prototype motor produces 10 kW maximum output power in the whole drive range 2000 - 22000 min⁻¹ and its efficiency is about 95% at maximum. It is confirmed that the efficiency improves by more than 20% at its best driving condition compared with that of a conventional steady-field-magnetic-flux IPMM in the low-output power region.