Performance Analysis of a Line-start Permanent Magnet Motor with Slots on Solid Rotor Using Finite-element Method

This article analyzes a line-start permanent magnet motor with a slotted solid rotor. The performance of the proposed line-start permanent magnet motor is simulated using the finite-element method. Slotting the solid rotor will increase the electromagnetic torque for synchronization. This means the motor with a solid rotor can reach synchronous speed with higher loads than with the smooth rotor. In addition, this study considers the impacts of the number and type of slots of the solid rotor on the motor performance. It is concluded that skewing the solid rotor in the direction of rotation makes the motor reach synchronous speed with higher constant loads than a non-skewed rotor. In addition, the maximum torque depends on the number of slots; for example, 12 for the case-study machine. At the end, a 3-phase, 4-pole, 1500-rpm, 750-watt synchronous motor with a slotted solid rotor is designed and built to confirm experimentally the finite-element method model.