I. Introduction
Inverter driven Induction Motors (IMs) are mainly adopted for applications where a wide and continuous range of operating speed is required. However, in many cases the cost of the drive unit itself could exceed the cost of the actual motor. Therefore, for two-speed applications such as desert coolers, the speed change is normally done through the pole-changing concept as opposed to the use of a drive unit. However, IMs normally operate at low power factor and efficiency duo to the motor slip. Line Start Permanent Magnet (LSPM) synchronous motor is another type of self-starting motor but with a higher efficiency, power factor, and power density [1]-[6]. The magnetic flux generated by the Permanent Magnets (PMs) gets locked in with the rotating three phase stator field, which eliminates the motor slip. Despite the advantages, the fixed polarity of the rotor poles had always prevented incorporating the pole-changing concept in LSPM motors.