Single-phase motor speed regulating circuit

Single-phase motor speed regulating circuit

Shown is the detection of a single-phase speed-regulated motor and power supply system. The motor has two windings, AC 220 V power supply, and one end is added to the common end of
the winding . The running winding is connected to the other end of the AC 220 V through the bidirectional thyristor D2, and is connected to
the terminal of the auxiliary winding through the 4tiF capacitor.
    Only when D2 in the main channel of the motor is turned on can power be added to the winding and the motor rotate. D2 is controlled by Di.
D1 outputs pulses within half an AC cycle, and D2 becomes conductive. The speed can be controlled by changing the conduction angle (phase) of Di.