Accurate estimation method for rotating speed of motor of servo system

Abstract

The invention discloses an accurate estimation method for the rotating speed of a motor of a servo system. Firstly, a motor rotor angle signal output by an encoder is preprocessed, specifically, in each sampling period, an angle value obtained in the subsequent sampling period is corrected according to an average rotating speed value calculated when continuous pulses are detected by a previous controller on the basis of the idea of interpolation, and a smoother angle signal is obtained. Then, based on the integrator series type model of the controlled object, a corresponding linear expansion state observer is established, namely the preprocessed motor rotor angle value is input into the linear expansion state observer, a proper error feedback gain value is selected according to an error feedback principle, and accurate angle, rotating speed and acceleration observation values of the motor rotor can be output by the linear expansion state observer. The high-precision motor rotating speed estimation method based on the low-resolution encoder is achieved, and the speed measurement requirement of the high-performance motor low-speed servo system can be met.

Description

technical field [0001] The invention relates to the technical field of motor rotation speed detection in a servo system, in particular to a method for accurately estimating the rotation speed of a motor when a low-resolution encoder is used for angle detection when the motor is running at a low speed. Background technique [0002] In the motor low-speed servo control system, in order to allow the motor to achieve high position or speed tracking accuracy under low-speed or even ultra-low-speed operation, the angle measurement device is required to provide accurate motor rotor angle and speed measurement values ​​to the controller. However, in some specific application scenarios, the resolution of the selected encoder is often limited due to comprehensive consideration of cost performance, reliability, and solution feasibility. When the motor is running at a low speed, continuous multiple If the angle value obtained by sub-sampling does not change, the measurement device will ...

AI Technical Summary

Problems solved by technology

The state observer method can effectively estimate the motor speed in real time, but most of the observers are too dependent on the plant model and its related parameters, which leads to the fact that in practical applications, due to unknown system parameters or time-varying not effectively

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