Finite-Time Chattering-Free Discrete Sliding Mode Control of Uncertain Nonlinear MIMO System Including Limit-Cyclic Channel Interaction

In this paper, a new discrete-time sliding mode control (DSMC) method is proposed for the strongly nonlinear multi-input multi-output (MIMO) van-der-Pol system which without introducing undesired chattering effects guarantees finite-time convergence to a predefinedsliding invariant set and ensures closed-loop stability of the overall system in presence of multiple modes of modeling uncertainties and time delay effects. To this end, the sliding hyperplane is constructed while considering parametric uncertainty and externaldisturbances for each subsystem of the overall MIMO system. Modeling uncertainties are effectively incorporated into the construction of control system which results in obtaining appropriate control bounds. Control signals are selected using a proximity factorwithin the calculated bounds which ensures elimination of chattering in all control inputs while maintaining the important quality of finite-time convergence. The proposed algorithm can be considered as a general method for finite-time sliding control of various classesof nonlinear MIMO systems. As no switching term is included in obtaining control signals, no undesired chattering effects are observed in any of control inputs, which can be cited as a significant improvement compared to the existing methods. Effectiveness andaccuracy of the proposed algorithm has been demonstrated through numerical calculations.

کلیدواژه ها:

Discrete-Time Control ، Finite-Time Convergence ، Parametric Uncertainty ، Reference Tracking ، Sliding Mode Control