Single-phase asynchronous motor refers to a low-power single-phase asynchronous motor powered by a single-phase AC power supply (AC220V). Its power is designed to be relatively small, generally not greater than 2kW. Single-phase asynchronous motors account for most of the low-power asynchronous motors, and have been modified four times, that is, through four unified designs. Different occasions have very different requirements for motors, so it is necessary to use various types of motor products to meet the requirements of use.
Generally, single-phase asynchronous motors are divided into the following five types according to the characteristics of the starting and running modes of the motor.
1. Single-phase resistance start asynchronous motor. Code JZ BO BO2
2. The single-phase capacitor starts the asynchronous motor. Code JY CO CO2 New code: YC
3. The single-phase capacitor runs the asynchronous motor. Code JX DO DO2 New code: YY
4. Single-phase capacitors start and run asynchronous motors. Code YL
5. Single-phase shaded-pole asynchronous motor.
Since the output power of the motor is not large, the rotor of the general single-phase asynchronous motor adopts a squirrel-cage rotor, and its stator has a set of working windings, called the main winding stage, which can only generate positive and negative voltage in the air gap of the motor. The negative alternating pulsed magnetic field cannot generate a rotating magnetic field, therefore, it cannot generate starting torque. In order to generate a rotating magnetic field in the air gap of the motor, it is necessary to have a set of auxiliary windings, called the auxiliary winding. Because the magnetic field generated by the auxiliary winding and the magnetic field of the main winding are combined in the air gap of the motor to generate a rotating magnetic field, at this time, the motor generates a rotating magnetic field. Starting torque, therefore, the rotor of the motor can turn itself.
Its stator is embedded with a main phase winding and a secondary phase winding, and the two windings and the axis form an electrical angle of 90 degrees in space. The secondary phase winding is generally connected in series with an external resistor through the centrifugal head, connected in parallel with the main phase winding, and connected to the power supply together. When the motor is started until the speed reaches 75%~80% of the synchronous speed, the centrifuge is opened, and the contact of the centrifugal switch piece is de-energized.
It is basically the same as the single-phase resistance starter motor, and there are also two sets of windings on the stator with the main phase and the auxiliary phase forming an electrical angle of 90 degrees. The secondary winding and the external capacitor are connected to the centrifugal switch, connected in parallel with the main winding, and connected to the power supply together. Also, when the synchronous speed reaches 75%~80%, the secondary phase winding is cut off and becomes a single-phase motor. The power of this motor is 120W~750W.
The stator winding of this kind of motor is also two sets of windings, and the structure is basically the same. The operating technical indicators of the capacitor-operated motor are better than those of other previous types of motors. Although it has good running performance, the starting performance is relatively poor, that is, the starting torque is low, and the larger the capacity of the motor, the smaller the ratio of the starting torque to the rated torque. Therefore, the capacity of the capacitor running motor is not large, generally less than 180W.
Single-phase capacitor starting and running asynchronous motors
This kind of motor connects two capacitors in the secondary phase winding, one of which is through the centrifugal switch, and cuts off the power supply after starting; the other always participates in the work of the secondary winding. Among these two capacitors, the starting capacitor has a large capacity, while the running capacitor has a small capacity. This single-phase capacitor starting and running motor combines the advantages of single-phase capacitor starting and capacitor running motors, so this motor has relatively good starting performance and running performance. In the same frame size, the power can be increased by 1~2 A capacity level, the power can reach 1.5~2.2kW.
Single-phase shaded pole
It is an asynchronous motor with a simple structure, generally using a salient pole stator, the main winding is a concentrated winding, and the secondary phase winding is a single-turn short-circuit ring, which is called a cover-level coil. The performance of this kind of motor is poor, but due to its solid structure and low price, the production volume of this kind of motor is still very large, but the output power generally does not exceed 20W.
Add: No. 98, Minhe Road, Zeguo Town, Wenling City, Taizhou City, Zhejiang Province