A robust adaptive controller for systems with arbitrary zeros

A robust adaptive controller for single-input single-output systems with arbitrary zeros is presented. The control strategy is based upon the direct control algorithm of Hahn and Unbehauen (1982). The basic idea is to divide the controller into an adaptive and a nonadaptive part. By a certain choice of the nonadaptive controller parameters the robustness of the adaptive controller to unmodelled dynamics of the plant can be increased. The nonadaptive controller can be reformulated as a bypass to the plant. The adaptive controller is then acting on an augmented plant. A brief sketch of the theoretical background containing the derivation of the control law and the error model is presented. The stability theorem for robust adaptive control for systems with arbitrary zeros is discussed. An automatic tuning procedure for the correction network is presented. Some information about the turbogenerator model and hints for the implementation of the proposed adaptive controller are given