Speed control method for asynchronous motor

Abstract

The invention discloses a speed control method of asynchronism electromotor, the steps are following: sampling the real speed value of the asynchronism electromotor; the real speed value sampled is Laplace transformed, and then it is statistical treated to obtain the speed static difference value; ensuring the slip-form line parameter and the plus parameter according to the speed static difference value and load; Operating by itself to adjust the speed static difference and acceleration based on ensured parameters; judging whether the speed static difference is zero. The method can decrease the rely on electromotor parameter identification, and it is not sensitive to the change of parameters, it decreases the speed static difference and dithering of torsion, adds stability of equipment and device drive by the asynchronism electromotor, there will not overshoot when electromotor is started or trigged, the response time is short, and robustness is increased.

Description

technical field [0001] The invention relates to the speed control of an asynchronous motor, and more specifically refers to a speed control method of an asynchronous motor in the production process of the iron and steel metallurgical industry. Background technique [0002] In the production practice of the iron and steel metallurgical industry, asynchronous motors are mainly used in rolling mills, various shearing machines and various equipment for controlling roller tables. In the current world advanced motor control field, there are vector control methods and direct torque control methods. , Speed ​​sensorless speed regulation method and constant voltage frequency ratio (V / f) control method, etc. Both the sliding mode controller and the (PI) controller can be used in the vector-controlled asynchronous motor. For the vector-controlled asynchronous motor system, see figure 1 . figure 1 Shown is a common asynchronous motor vector control system in industrial control, M is a...

AI Technical Summary

Problems solved by technology

[0006] In the asynchronous motor vector control system, generally speaking, the speed, flux and torque adjustment controllers all adopt the PI (proportional integral) control method, and its main disadvantages are: poor system stability, overshoot when starting or braking , the response time required to start to the normal speed is long, etc., and the resulting consequences are: when the shearing machine scissors are trimming the edge and cutting the head, if the cutting operation requires high process dimensional accuracy, sometimes the shearing error will occur. Poor cutting effect, low precision and other defects, resulting in high scrap rate

Images