Effect of slot shape in rotor of electrical motor with high-speed spindle on slot ripples

Due to the slot ripples, there is often a strong additional torque which decreases the performance of electrical motor. In this paper, air gap flux densities of rotors with the pear-shaped slot, circular slot and trapezoidal slot are simulated and analyzed with ANSYS. The results show that the effects of the three kinds of shapes of rotors on the slot ripples are different, and the most inhibition to slot ripples is the rotor of pear-shaped slot. These results are very helpful for the optimal design of electrical motor with high-speed spindle.