Online Estimation of the Adhesion Coefficient and Its Derivative Based on the Cascading SMC Observer

The adhesion coefficient of wheel-rail surface cannot be directly measured, so a cascaded sliding-mode observer is proposed to observe adhesion coefficient and its derivative. A kinetic model for running heavy-duty locomotive is also established. The state equation of wheel adhesion control system i...

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Bibliographic Details
Main Authors: Changfan Zhang, Jian Sun, Jing He, Linfan Liu
Format: Article
Language:English
Published: Hindawi Limited 2017-01-01
Series:Journal of Sensors
Online Access:http://dx.doi.org/10.1155/2017/8419295
Description
Summary:The adhesion coefficient of wheel-rail surface cannot be directly measured, so a cascaded sliding-mode observer is proposed to observe adhesion coefficient and its derivative. A kinetic model for running heavy-duty locomotive is also established. The state equation of wheel adhesion control system is derived from the equation of traction motor torque balance, and adhesion coefficient is proposed to be calculated by load torque. Then, the cascaded sliding-mode observer is designed, and its stability is justified by Lyapunov stability. Based on the equivalence control principle for sliding-mode variable structure, an algorithm to estimate adhesion coefficient and its derivative is established. The simulation and experimental results are used to verify the effectiveness of the observer with load variations or wheel-rail status changes.
ISSN:1687-725X
1687-7268