Delta-Modulated Feedback in Discretization of Sliding Mode Control
Abstract
Modulated feedback control introduces periodicity. The globalattracting property of the periodic points is established for asimple scalar discrete-time system under Delta-modulatedfeedback. Attracting regions of the periodic points are alsocharacterized. When the discretization effects of the equivalentcontrol based sliding mode control systems are studied, we showthat the zero-order-hold discretization gives rise toDelta-modulation in the sliding mode direction. The globalattracting property of Delta-modulated feedback offers a vividillustration of the way sliding happens. Interestingly, we findthat a ZOH discretization scheme of the equivalent control basedsliding mode control system with relative degree one results inonly two-periodic orbits.
