Open AccessNovel Nonsingular Fast Terminal Sliding Mode Control for a Class of Second-Order Uncertain Nonlinear Systems
Author(s) -
Huihui Pan,
Guangming Zhang
Publication year - 2021
Publication title -
mathematical problems in engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.262
H-Index - 62
eISSN - 1026-7077
pISSN - 1024-123X
DOI - 10.1155/2021/8840244
Subject(s) - control theory (sociology) , invertible matrix , nonlinear system , robustness (evolution) , controller (irrigation) , terminal sliding mode , mathematics , lyapunov stability , exponential stability , sliding mode control , computer science , control (management) , physics , biochemistry , chemistry , quantum mechanics , artificial intelligence , biology , pure mathematics , agronomy , gene
This paper presents a novel nonsingular fast terminal sliding mode control scheme for a class of second-order uncertain nonlinear systems. First, a novel nonsingular fast terminal sliding mode manifold (NNFTSM) with adaptive coefficients is put forward, and a novel double power reaching law (NDP) with dynamic exponential power terms is presented. Afterwards, a novel nonsingular fast terminal sliding mode (NNFTSMNDP) controller is designed by employing NNFTSM and NDP, which can improve the convergence rate and the robustness of the system. Due to the existence of external disturbances and parameter uncertainties, the system states under controller NNFTSMNDP cannot converge to the equilibrium but only to the neighborhood of the equilibrium in finite time. Considering the unsatisfying performance of controller NNFTSMNDP, an adaptive disturbance observer (ADO) is employed to estimate the lumped disturbance that is compensated in the controller in real-time. A novel composite controller is presented by combining the NNFTSMNDP method with the ADO technique. The finite-time stability of the closed-loop system under the proposed control method is proven by virtue of the Lyapunov stability theory. Both simulation results and theoretical analysis illustrate that the proposed method shows excellent control performance in the existence of disturbances and uncertainties.