A second-order sliding mode control method for magnetically suspended switched reluctance motor

Abstract

A second-order sliding mode control method for magnetically suspended switched reluctance motor is disclosed in the invention. The speed loop adopts the second-order sliding mode speed controller based on the superscrew algorithm, The reference torque is obtained by selecting the speed error to construct the sliding mode surface and combining with the mechanical equation of the maglev switched reluctance motor. The displacement loop adopts the second-order sliding mode displacement controller based on the improved superscrew algorithm, A high order error derivative of displacement is introduced to make the superhelix algorithm suitable for second order systems, The reference levitation force is obtained by improving the superscrew algorithm combined with linear compensation term. The invention adopts a second-order sliding mode speed controller based on a superscrew algorithm and a second-order sliding mode displacement controller based on an improved superscrew algorithm, The speed control precision and rotor suspension precision of SRM are improved, the problems of speed buffeting and displacement buffeting are solved, and the system has strong robustness to uncertain disturbance, which is easy to be realized in engineering.

Description

technical field [0001] The invention relates to a second-order sliding mode control method for a magnetic levitation switched reluctance motor, which is suitable for high-performance control of the magnetic levitation switched reluctance motor and belongs to the technical field of electric drive control. Background technique [0002] The magnetic levitation switched reluctance motor combines magnetic bearing and switched reluctance motor technology, which can realize the two-degree-of-freedom levitation of the motor and generate electromagnetic torque at the same time, and shorten the axial length of the motor on the basis of retaining the characteristics of no friction and no mechanical wear of the magnetic bearing , effectively increasing the critical speed of the motor. It has many advantages such as excellent speed regulation performance, strong fault tolerance, simple structure, and low cost. It has broad application prospects in flywheel batteries, space vehicles, biom...

AI Technical Summary

Problems solved by technology

However, the traditional first-order sliding mode is essentially a switching function of discontinuous control, which has inherent chattering problems. The magnetic levitation switched reluctance motor adopts a "double salient pole" structure, and the current commutation and the levitation force between individual tooth poles , Torque conversion will bring system chattering problems, and the chattering problems of the motor and controller will stimulate the unmodeled characteristics of the system

[0005] At present, the methods for reducing sliding mode chattering mainly include approach law and boundary layer method, both of which belong to the category of first-order sliding mode, and cannot completely eliminate chattering

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