A Multiestimation Scheme Using Different Froh-Discretizations

A multiestimation scheme for adaptive discrete control is presented. The different models of the scheme to be estimated are obtained from a set of different discretizations of a continuous unknown transfer function under a fractional order hold of correcting gain betaisin[-1,1] (beta-FROH). The objective is to design a scheme which is able to find the most appropriate value for the gain beta. An identification performance index evaluates each identifier and the scheme chooses the one with the lowest value. In order to improve the behavior between two consecutive sampling instants, another switching rule is presented. This rule is used once the identification has finished. The switching rule is subjected to a minimum residence time in order to guarantee the closed loop stability. Simulations are presented to show the usefulness of the multiestimation scheme