Anti-disturbance Optimal Control of Nonlinear Systems Based on Multi-source Disturbances

For a class of nonlinear systems with multi-source disturbances, this article discusses the problem of optimal control and anti-disturbance control. The plant considered is a nonlinear system wherein matched and mismatched disturbances exist simultaneously. A nonlinear disturbance observer (DO) is constructed to dynamical estimate and reject the matched disturbance in the input channel. In the meantime, according to optimal control theory, a controller is designed to reduce the impact of the mismatched disturbance and enhance the nonlinear system's ability to resist disturbance. Further, a stability criterion and an optimal control strategy are obtained by employing Lyapunov stability theory and adaptive dynamic programming (ADP) method. Finally, the performance of the proposed control scheme is validated through a series of comparative simulations.