Affiliations: Department of Mathematics and Computer Science, Lorestan University, Lorestan, Iran
Correspondence:
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Corresponding author. Majid Yarahmadi, Department of Mathematics and Computer Science, Lorestan University, Lorestan, Iran. Tel.: +989166653079; Fax: +986633120618; E-mail: yarahmadi.m@lu.ac.ir.
Abstract: In this paper, a new indirect fuzzy sliding mode control with varying boundary layer is presented for uncertain nonlinear systems via time-variant sliding function in the presence of external disturbances. Based on rejection parameter and rejection regulator, a time-variant sliding surface as an adaptive filter is defined. This time-variant sliding surface based on an adjustable rejection parameter filters all the un-modelled frequencies. An adjustable boundary layer width, break-frequency bandwidth and the consequent parameters in fuzzy rules are tuned to attenuate the effects of the system uncertainties and un-modelled frequencies, efficiently. Also, the chattering phenomenon is completely eliminated. Three theorems and one lemma, which facilitate design of the proposed controller, are proved. Two simulation examples are presented to illustrate the performances and the advantages of the proposed method.
