Strictly speaking, can not distinguish between high and low voltage motors, the so-called 220V, 380V is just short of our daily, it should be said here, single-phase and three phase.

Depend on the current rotation of AC motor produces a rotating magnetic field. Flow through the three-phase motor is 120 degrees phase difference-phase current, can produce a rotating magnetic field. The single-phase motors off single-phase current flow can not produce a rotating magnetic field, it needed some way to produce a rotating magnetic field, with the motor capacitor is one of the methods is the most common method.

Single Phase capacitor is used, the purpose is to enable the two currents Rao group phase difference of nearly 90 ゜ to produce a rotating magnetic field. Three-phase electricity, each two-phase phase difference between the current itself, without phase separation.

Capacitor induction motor has two windings, the starting winding and running winding. Difference between the two windings in the space of 90 degrees. Start a thread winding large-capacity capacitors, when running through the single winding and AC start winding, due to the role of the start winding in capacitor current in time than the run winding current to lead the 90-degree angle, first to reach the maximum value. Formed in time and space of two identical magnetic field, so that the air gap between stator and rotor of a rotating magnetic field generated in the rotating magnetic field, the electrical current induced in the rotor, the current interaction of the rotating magnetic field electromagnetic torque, the motor spin.