A method for controlling a permanent magnet synchronous motor

Abstract

The invention discloses a permanent magnet synchronous motor control method, which improves the dynamic performance and tracking characteristics of the system through feedforward control, and uses a sliding mode controller with a load disturbance observer to improve the anti-disturbance performance of the system, forming a position Structure of speed compound controller. Among them, the discrete terminal sliding mode surface improves the convergence speed of the system error state near the equilibrium point. The sliding mode approach rate adopts the form of a piecewise function. When the system error state is far away from the sliding mode surface, the approach rate has a large gain, which can achieve the effect of rapid approach; when the system error state is close to the sliding mode surface , the rate of approach decreases as the position error decreases, thereby suppressing the "chattering" phenomenon of the sliding mode. Compared with the traditional sliding mode approach rate whose sliding mode gain is constant, the proposed sliding mode approach rate has a sliding mode bandwidth that increases or decreases with the increase or decrease of the position error, and is approximately 0.5k at the equilibrium point 2 T; After adding the observer feedforward, the tracking accuracy of the motor position and speed has been improved.

Description

technical field [0001] The invention belongs to the technical field of servo motor control, and in particular relates to a method for controlling a permanent magnet synchronous motor. Background technique [0002] The servo system is a concept in the control system, which is used to control a certain state of the controlled object (generally position, speed and torque), so that it can continuously and accurately track the changes of the input signal. AC servo systems are widely used in various fields of society, ranging from aerospace, military, industrial manufacturing and other fields to small office and teaching automation equipment. According to the type of executive motor, the servo system can be divided into DC servo system and AC servo system. With the improvement of the stability and accuracy requirements of the servo system in the modern market, the high-performance AC servo system gradually occupies a dominant position. The structure of the servo system is compos...

AI Technical Summary

Problems solved by technology

However, in order to suppress external disturbances (such as changes in load torque), traditional SMCs need to increase the gain of the control law, resulting in discontinuous control signals and severe high-frequency chattering

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