Design and analysis of an axial-flux PM vernier machine for auto-focusing systems

This paper proposes a low-speed, high-torque, axial-flux permanent magnet vernier motor (PMVM) for the auto-focusing system application. The proposed motor is designed by precisely taking into consideration of the limited lens dimensions and camera installation space. The design approach of the vernier motor is an alternative combined design solution, coupled with the analytical method and finite element method (FEM). Based on the initial design, the parameter sensitivity analysis is finally carried out to further reduce cogging torque and torque ripple while maintaining the required output torque.