This paper studies the high inertia surface mount permanent magnet servo motor with 130mm frame size. First, the motor with five pole slot combinations is designed, including 12 slots 8 poles, 12 slots 10 poles, 12 slots 14 poles, 18 Slots 16 poles and 36 slots 10 poles. Secondly, the cogging torque and torque ripple are optimized by the permanent magnet eccentric method. Finally, using finite element simulation to compare the electromagnetic performance under different combinations of pole and slot numbers, including power density, torque ripple, overload capacity, loss and efficiency, etc., the advantages and disadvantages of different motors are obtained. Among them, the 36-slot 10-pole motor has the best overload capacity and the most stable output torque; the 18-slot 16-pole and 12-slot 14-pole motors have high power density, but the overload capacity is the worst; 12-slot 8-pole has a higher overload multiple, But the torque ripple is the largest and the power density is the smallest, which makes it unsuitable for high-inertia servo motors; 12-slot 10-pole motors have all the advantages and are worth mass production.
 

servo motor,slot-pole combinations,cogging torque,magnet eccentric method,overload capacity