Modified Implicit Discretization of the Super-Twisting Controller

• 成果类型: Article
• 署名作者: Andritsch, Benedikt; Watermann, Lars; Koch, Stefan; Reichhartinger, Markus; Reger, Johann; Horn, Martin
• 署名单位: Graz University of Technology; Technische Universitat Ilmenau; Graz University of Technology
• 刊物名称: IEEE TRANSACTIONS ON AUTOMATIC CONTROL
• ISSN/ISSBN: 0018-9286
• DOI: 10.1109/TAC.2024.3370494
• 发表日期: 2024
• 页码: 5620-5626
• 关键词: Steady-state; Perturbation methods; Closed loop systems; CONVERGENCE; Noise measurement; Doppler effect; automation; Backward Euler discretization; discrete-time control; implicit discretization; Sliding mode control; super-twisting algorithm; super-twisting control

摘要

In this article, a novel discrete-time realization of the super-twisting controller is proposed. The closed-loop system is proven to converge to an invariant set around the origin in finite time. Furthermore, the steady-state error is shown to be independent of the controller gains. It only depends on the sampling time and the unknown disturbance. The proposed discrete-time controller is evaluated comparative to previously published discrete-time super-twisting controllers by means of the controller structure and in extensive simulation studies. The continuous-time super-twisting controller is capable of rejecting any unknown Lipschitz-continuous perturbation and converges in finite time. Furthermore, the convergence time decreases, if any of the gains is increased. The simulations demonstrate that the closed-loop systems with each of the known controllers lose one of these properties, introduce discretization-chattering, or do not yield the same accuracy level as with the proposed controller. The proposed controller, in contrast, is beneficial in terms of the above described properties.