Discrete T–S fuzzy systems with time-varying delays: a new discrete sliding mode control approach

Abstract

The control of nonlinear systems has been the subject of extensive research. This interest is mainly due to its potential for real applications. In this paper, we investigated discrete sliding mode control for a class of nonlinear time-delay systems represented by T–S fuzzy models. In most existing fuzzy sliding mode control, a common input matrix is considered for all subsystems. This assumption is very restrictive. Therefore, we proposed a new sliding surface, which takes account of the system state and the control input in order to exclude the restrictive assumption. Furthermore, we have improved the latter sliding mode control scheme, by adding delayed states. Based on formulation of linear matrix inequalities, the parameters of the sliding function are obtained. Therefore, to further reduce the conservatism in the existing results, the Wirtinger-based integral inequality and Jensens inequality are employed. To show the applicability and effectiveness of the proposed controller design methodology, a numerical example is given for illustration.