In this seminar, the design of a 3-phase IM for an energy-efficient ceiling fan, along with a rotor optimization procedure to extract maximum torque from an IPMSM, is discussed. The details of the design with results will be presented in the seminar.

The use of rare-earth PM has benefited motors by increasing their torque density and efficiency, making PM-based motors a lucrative choice over induction motors (IM). Although for low power motors used in a household application like ceiling fans, the single-phase IM remains a popular choice over PM-based Brushless DC (BLDC) motors even though they are energy efficient. This is due to the high cost of PM used in the motor. Whereas the single-phase IM-based fans have poor efficiency due to higher losses because of their single-phase structure. A 3-phase IM with concentrated windings can offer a cost-effective and efficient solution to the ceiling fan market by overcoming the disadvantages present in the single-phase IM based ceiling fan. This can be achieved by an appropriate stator design of IM to improve its winding factor, as for concentrated wound motors with low pole pairs, the winding factor is low. A low pole pair and back-EMF value are selected for stator design to reduce the iron losses of the machine.

In contrast, for EVs, where interior magnet PMSM (IPMSM) is mostly used, the variation in rotor geometry affects the motor torque-speed characteristics. A study on the rotor geometry variations to extract maximum torque for a given PM volume and stator current is done and will be presented in the seminar.