Design of a Control Algorithm for Nonlinear Plant Using Correction of Controlled Plant Dynamics and Compensation of Perturbations

A new control algorithm for nonlinear, non-stationary multichannel plant, convenient for practical use, is obtained. The ideological basis of the algorithm construction is the compensation of external additive influences on the state variables and output variables of the plant with the accuracy of etalon filters by means of the inverse model of this plant. Unobservable perturbations are evaluated by the mismatch between the corresponding plant variables and the inverse model. Controlled plant is represented as a system of ordinary differential equations in normal form with the same number of output variables and control actions. Functional algebraic equations are presented, solution of which yields the inverse model and the etalon filters. The solution leaves a certain freedom of choice of the etalon filters, which determine the dynamic properties of the control system. The structure of the control system is composed, according to the compensation principle in which the output and state variables of the plant are used for the perturbation estimation. As a result, there is a feedback in the system, which was not postulated initially, but was the result of evaluation and compensation of perturbations with the accuracy determined by the etalon filters. This approach made it possible to determine the structure and parameters of the controller by analytical method using physically obvious initial data. А consequence of the compensation and filtering of perturbations affecting the state variables is the correction of the plant’s own dynamics. The effectiveness of the proposed algorithm is shown by examples.с