A Method for Estimating Rotor Position and Speed ​​of Permanent Magnet Synchronous Motor Based on Deadbeat Back EMF Predictor

Abstract

The invention relates to a method for estimating the rotor position and speed of a permanent magnet synchronous motor based on a deadbeat counter electromotive force predictor. The predicted value of the αβ-axis back electromotive force is calculated by the deadbeat prediction algorithm: the input of the deadbeat prediction algorithm is the actual voltage of the αβ axis, the actual current of the αβ axis and the estimated current of the αβ axis of the motor at the current moment, and the deadbeat prediction algorithm uses αβ The actual current of the axis is the target value, and the predicted value of the αβ axis back EMF is calculated; the predicted value of the αβ axis back EMF is input into the state estimation model, so that the estimated current of the αβ axis obtained by the state estimation model reaches the target value in the next sampling period, when the system After entering stability, the estimated current of the αβ axis tracks the actual current of the αβ axis in real time, so that the predicted value of the back electromotive force is equal to the actual value of the back electromotive force; the predicted value of the back electromotive force is low-pass filtered; the position and speed of the motor rotor are calculated through the phase-locked loop . The invention can improve the estimation performance of the position and speed of the permanent magnet synchronous motor.

Description

technical field [0001] The invention relates to a method for estimating the rotor position and speed of a permanent magnet synchronous motor based on a deadbeat back electromotive force predictor, and belongs to the field of motor control. Background technique [0002] The position sensorless technology can replace the mechanical position sensor, and is widely used in permanent magnet synchronous motor control systems in occasions such as low cost, poor operating environment, and harsh space requirements. The back EMF of permanent magnet synchronous motor contains angle and speed information, so the position sensorless control method based on back EMF observer is widely used, including sliding mode observer, Romberg observer, adaptive observer, extended Kalman filter device etc. The existing observers are all based on the actual system as a reference, and establish a state observation model based on the actual system, and correct the control variables or parameters of the o...

AI Technical Summary

Problems solved by technology

Then, as a closed-loop control system, the observer is a kind of time-lag deviation regulator because it needs to adjust the observation model according to the state deviation calculated in the previous period in the digital implementation. These regulators cause the system to have response delay, overshoot, etc. Problem, the extended control delay under the condition of low carrier ratio will make the system performance worse or even unstable

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