​The working principle of the capacitive fan motor is based on the characteristics of the single-phase AC motor. The phase shifting action of the capacitor is used to generate a rotating magnetic field, which drives the motor to rotate and the fan blade to rotate to generate wind. The specific working process is as follows:

1. Magnetic field generation:

• Stator magnetic field: When single-phase AC is passed through the stator windings of the fan motor, an alternating magnetic field is generated. Since there is only a single phase alternating current, in the absence of other auxiliary measures, this magnetic field is a pulsating magnetic field, its direction and size will change with time, but will not rotate.

• Starting winding magnetic field: In addition to the main winding (running winding) on the stator, there is a starting winding. The starting winding and the main winding are usually 90 degrees electrical Angle apart in space. When a current passes through the starting winding, a magnetic field is also generated.

2. Phase shifting of capacitors: a capacitor is connected in series in the starting winding loop. Capacitors have a phase shift function in AC circuits, which causes the current through the starting winding to differ in phase from the current through the main winding. Due to the capacitance, the current in the starting winding is about 90 degrees ahead of the current in the main winding. In this way, at the same time, the magnetic field generated by the current in the main winding and the starting winding will also have a certain phase difference in space.

3. Formation of rotating magnetic field: Two windings with a 90 degree electrical Angle difference in space and a 90 degree current phase difference will generate a rotating magnetic field in the air gap between the stator and the rotor. This rotating magnetic field acts like a rotating magnet and exerts a magnetic effect on the rotor.

4. Rotation of the rotor: under the action of the rotating magnetic field, the conductor in the rotor cuts the magnetic field line, and according to the law of electromagnetic induction, the induced current will be generated in the rotor conductor. The induced current interacts with the rotating magnetic field to produce electromagnetic torque, which causes the rotor to start rotating.

5. Operation after starting: When the rotor speed rises to a certain extent, with the help of a centrifugal switch or other automatic control device installed on the rotor, the starting winding is disconnected. At this time, the fan motor mainly relies on the magnetic field generated by the main winding to maintain the rotation of the rotor, and the fan continues to work stably.