Control method for AC asynchronous motor output torque and its use

Abstract

The torque control is dependent on rotation difference control. Adjusting power frequency can adjust the rotation difference. Based on rotation speed and number of pole pair of motor, the invention adjusts power frequency, synchronous speed so as to adjust rotation difference, and adjusts voltage to realize adjustment of torque. In electric control, adjusting torque can adjusts tension, speed etc. In electricity generation, the method can adjust excitation. No matter in electric control state or in electricity generation state, the method always controls torque so that it is better to coordinate to the load in state of electric control, and it is better to coordinate to the drive in state of electricity generation. Since rotation difference is controlled in control procedure, thus, adjusting rotation difference can control efficiency of motor so as to obtain higher efficiency to convert electric energy to mechanical energy by electromotor, or vice versa by generator.

Description

technical field [0001] The invention relates to a control method and application of the torque of an AC asynchronous motor, including a method for controlling working conditions such as tension, rotating speed and efficiency by using these methods and the application in specific equipment. The motors described in this paper are AC asynchronous motors, including motors and generators. Background technique [0002] In the prior art, the torque motor is mainly operated by the torque control mode, and the principle is to adjust the torque by adjusting the voltage of the motor. Although the slip may change during the adjustment, the change of the slip is passive instead of actively adjusting the voltage and slip. When the torque motor controls the torque, its performance such as torque and efficiency is not very good, while other motors are not good. It is controlled by speed regulation and the output torque is not controlled separately in the process. Other equipment used for t...

AI Technical Summary

Problems solved by technology

Although the slip may change during the adjustment, the change of the slip is passive instead of actively adjusting the voltage and slip. When the torque motor controls the torque, its performance such as torque and efficiency is not very good, while other motors are not good. It is controlled by speed regulation and there is no separate control of the output torque in the process. Other equipment used for torque control, such as magnetic powder clutches, magnetic powder brakes, etc., have various shortcomings and cannot meet the requirements of various occasions.