Analysis of Oscillations in Relay Feedback Systems With Fractional-Order Integrating Plants

Abstract

Oscillatory behavior and transfer properties of relay feedback systems with a linear plant including a fractional-order integrator are studied in this paper. An expression for system response in the time domain is obtained by means of short memory principle, Poincare return map, and Mittag–Leffler functions. On the basis of this expression, the frequency of self-excited oscillations is approximated. In addition, the locus of perturbed relay system (LPRS) is derived to analyze the input–output properties of the relay system. The presented analysis is supported by a numerical example.