Output Control of Nonlinear Systems Using Modified Backstepping Algorithm with Disturbances Compensation

Abstract

The article deals with a tracking control system synthesis for a nonlinear plant functioning under bounded external disturbances which are not available for measurement. A proposed solution is a robust modification of the backstepping approach with the similar controller design structure. The main changes are based on plant model transformations that make it possible to use the only one filer in control system and, along with it, an auxiliary loop method usage to disturbances evaluation and compensation. High-gain observers are used for unknown signals measuring together with their derivatives. Tracking errors and observation errors convergence with the adjustable accuracy during the finite transient time is proved. Efficiency of the algorithm is demonstrated using computer modeling in comparison with an analogue.