Asynchronous electric motors are mainly used as motors. It is the most widely used and the largest amount of motor in the industrial and agricultural production and the national economy departments. Metal cutting machine tools, rolling mills, blowers, grinders, pumps, oil pumps, light machinery, textile machinery, mining machinery, etc., most of the use of asynchronous motor drive. In people's daily life, the application of asynchronous motor is also more and more widely, such as electric fans, washing machines, refrigerators, air conditioners and other household appliances, the use of single-phase asynchronous motor. In the electric drive, most of the traction motor is asynchronous motor, and its power consumption accounts for about 60% of the total power grid load.
Asynchronous electric motor has been widely used because it has the advantages of simple structure, convenient operation, reliable operation, high efficiency, easy manufacture and low cost.
The asynchronous electric motor itself has poor speed regulating performance, and the DC motor is usually used in the case of requiring a wide range of smooth speed regulation. In the past ten or twenty years, the asynchronous motor AC speed regulation system based on power electronic devices and microcomputers has improved the speed regulating performance of asynchronous motor, so its use is more extensive.
Asynchronous electric motor, must absorb reactive power from the grid, the grid power factor variation. Because the power factor of the power grid can be compensated by other methods, this point does not prevent the widespread use of the asynchronous motor.