Single-phase motor reactor voltage reduction speed regulation circuit

As shown in the figure, the reactor is connected in series to the power supply circuit of the single-phase motor, and the voltage reduction speed regulation is achieved by switching the coil tap of the reactor. When the speed control switch SA is turned to "I", the main winding LR and the reactor L are connected to the power supply in series, and part of the power supply voltage will fall on all coils of the reactor L. Therefore, the working voltage of the main winding LR decreases, and the power generated by LR When the magnetic field weakens, the slip of the motor increases and the speed decreases significantly; when SA is set to "Ⅲ", the main winding operates at the rated voltage and the speed reaches the highest; when SA is set to "Ⅱ", the working voltages of LR and LA are between Between high speed and low speed, so it is medium speed.