capacitor induction motor

A capacitor induction motor is a type of single-phase electric motor that uses a capacitor to create a rotating magnetic field, enabling it to start and run. Unlike three-phase motors that naturally produce a rotating field, single-phase motors require an auxiliary method to generate this field from a single power supply.12

In a capacitor induction motor, there are two stator windings. The main winding connects directly to the power supply. An auxiliary winding is connected through a capacitor, which causes the current in this winding to lead the current in the main winding by approximately 90 degrees. This phase difference creates the necessary rotating magnetic field and starting torque.1

As the motor reaches its operating speed, the auxiliary winding and capacitor are often disconnected by a centrifugal switch, as the main winding alone can sustain the rotating field. These motors are common in applications requiring high starting torque, such as refrigerator compressors and pumps.1