Single-phase motor winding tap L-1 connection two-speed circuit

Capacitor-run motors now generally adopt the method of stator winding tap speed regulation. This speed regulation method is different from autotransformer or reactor speed regulation. It only needs to change the wiring of the stator winding. It has the characteristics of saving materials, light weight and low power consumption. The disadvantage is that the winding, embedding and wiring of the coil are troublesome. Using winding tap speed regulation, the stator of the motor must have a speed regulating winding embedded in addition to the main winding and auxiliary winding. By changing the tap of the speed regulating winding, the voltage drop and magnetic field strength of the main winding are changed, thereby achieving the purpose of speed regulation of the motor. The picture shows the schematic diagram of L-1 type two-speed speed regulation. In the figure, the speed regulating winding LD is connected in series with the main winding LR and then directly connected to the power supply. In this connection method, LD and LR are distributed in the same slot, so they are in the same phase in space. The speed regulating winding is embedded on top of the main winding, and its wire diameter is 20% to 30% smaller than the main winding. When the speed control switch SA is turned to "1", the motor runs at high speed. At this time, the speed control winding ld is all connected in series to the auxiliary winding LA, and the main winding LR is directly connected to the entire power supply voltage. The operating performance is good and the speed is high. . When SA is set to "2", all the speed regulating winding LD is connected in series to the main winding LR, which means that the number of turns of the main winding increases a lot and the magnetic flux decreases a lot, so the motor enters a low-speed operation state.