Study on Improving the Durability of Shaded Pole Induction Motors Used for Refrigerator Fans

The shaded pole induction motor is simply a selfstarting single-phase induction motor whose one of the poles is shaded by the copper ring. Even though it has poor efficiency and the starting torque is very low, it is widely used, because of low cost and easy starting. The shaded pole induction motors used in cooling fans in refrigerators are generally well used, but in areas where the power supply is unstable, it sometimes leads to the faults such as motor coil disconnection. In this paper, the fan load tests and the locked rotor tests were performed in order to determine the operation status of the motor in overvoltage conditions. Through some experimental studies, it was found that the durability of the motor would be improved if the coil diameter became reduced and the coil lengthened even in overvoltage conditions.