Research on Magnetic Suspension Control Scheme Based on Feedback Linearization under Low Track Stiffness

Abstract

The problem of vehicle–guideway coupled self-excited vibration is common in maglev train systems, which has a serious impact on the stability of maglev trains. The lower the track stiffness, the more likely it is to occur, the greater the harm to the maglev system, and the greater the difficulty in suppressing the vibration. To solve this problem, many conventional control schemes rely on the estimation of electromagnetic forces. However, considering the magnetic leakage flux in the suspension air gap and other reasons, the empirical electromagnetic force model is inaccurate, which increases the difficulty of suspension control under low track stiffness. Therefore, a more accurate electromagnetic force model based on least squares fitting is proposed in this paper, which can estimate the electromagnetic force more accurately without increasing the computational cost. On this basis, a control scheme based on feedback linearization theory was designed, and the control effect was tested on an experimental platform with low track stiffness. The experimental results showed that the proposed control scheme could achieve stable suspension with low track stiffness and could effectively solve the vehicle–guideway coupled vibration problem with a strong anti-interference ability. The research in this paper is of great significance for solving the problem of vehicle–guideway coupled vibration under low track mass/stiffness, which is believed to be used in the light-weight girders in the next generation of commercial maglev systems. This work also has an important reference value for suspension control algorithms based on electromagnetic force feedback.