A speed-sensorless control strategy for linear traction motors based on phase-locked loop

Abstract

The invention discloses a speed-sensorless control strategy of a linear traction motor based on a phase-locked loop, and obtains a secondary counter electromotive force signal according to a voltage model of a linear induction motor α , β component; on this basis, the secondary back EMF signal α , β carry out dq transform, get d - q Shaft back electromotive force component; then, use the pre-filter to filter out the low-order harmonics of the secondary back electromotive force, and then filter the d - q The magnitude of the shaft back electromotive force is normalized, and finally the estimated speed is obtained by using a frequency-locked loop. In addition, small-signal modeling is carried out on the implemented velocity estimation scheme, and the tuning parameters in the scheme are designed to obtain better velocity estimation performance. The speed estimation algorithm adopted in the present invention has the characteristics of easy implementation, small calculation burden and strong robustness, and can design control parameters, making up for the heavy calculation burden, low robustness and low robustness of the existing linear traction motor speed estimation method. The technical problem that the control parameters are difficult to tune.

Description

technical field [0001] The invention relates to the technical field of electric traction AC transmission, in particular to a speed-sensorless control strategy of a linear traction motor based on a phase-locked loop. Background technique [0002] Urban rail transit has become the best solution to the congestion problem in major cities in China due to its energy-saving, land-saving, large-capacity, all-weather, low-pollution, safe, comfortable, and punctual features. However, the traditional urban rail transit has encountered a development bottleneck. The traditional subway and light rail cannot meet the requirements of the growing cities for reducing the turning radius and increasing the climbing ability. had a great impact. As a very promising urban rail transit system, the medium-low speed maglev driven by the linear traction motor has the following characteristics: the vibration and noise are small during the running of the train; the turning radius of the train is small ...

AI Technical Summary

Problems solved by technology

[0006] In view of the above problems, the purpose of the present invention is to provide a speed-sensorless control strategy for linear traction motors based on phase-locked loops that is easy to implement, has a small computational burden, and is robust, and can design the tuning parameters of the control system to obtain better Good speed estimation performance makes up for the technical problems of heavy calculation burden, low robustness and difficult tuning of control parameters in the existing linear traction motor speed estimation method

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