Nonsingular terminal sliding mode control for a class of 3-order nonlinear systems
PU Ming
JIANG Tao
LIU Peng
Abstract：Traditional nonsingular terminal sliding mode control cannot be used for 3-order systems. To solve this problem, a novel nonsingular terminal sliding mode control for a class of 3-order nonlinear systems with uncertainties and disturbances is proposed. Firstly, the dynamic surface of Backstepping control is combined with 2-order nonsingular termi-nal sliding mode control (TSMC) to construct the 3-order nonsingular terminal sliding modes. Then, the approximations of negative fractional exponential terms are obtained by higher-order sliding mode differentiator (HOSMD) to eliminate the singularity. Then, nonlinear disturbance observer (NDO) is used to approximate unknown uncertainties and disturbance. Terminal attractor is used as reaching law to avoid controller chattering. Based on finite time stability Lyapunov theorem, it is proved that the proposed scheme will force system states into an arbitrary small neighborhood including the origin in finite time. The proposed scheme has faster convergence speed than recursive linear sliding mode control (RLSMC) and other nonsingular TSMC (NSTSMC). In simulation, the total error of the proposed method decreased at least 18%compared with other sliding mode controllers. Overshoot and convergent time are also decreased significantly.
Keywords：nonsingularsliding mode controldifferentiatornonlinear systemsdynamic surface
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 683-691 )