Robust adaptive control for uncertain nonlinear systems with odd rational powers, unmodeled dynamics, and non-triangular structure?

Numerous approaches have been reported for different control problems of low-order triangular nonlinear systems. Nevertheless, it shows that the dynamic models of some practical plants are high-order nonlinear systems with odd rational powers. Besides, these systems constantly possess a non-triangular form and suffer from the impact of unmodeled dynamics. The related studies of such systems are very few and more challenging. This work concentrates on adaptive control issue of high-order nonlinear system with odd rational powers, unmodeled dynamics, and non-triangular structure. Based on the small-gain theorem, and by employing the adaptive technique, adding a power integrator method, and neural network method, we successfully construct a new adaptive controller, which greatly decreases the use of parameter estimations in the adaptive control of the considered system. An example highlights that the strategy regulates the studied systems well and performs satisfied system responses.(c) 2021 Published by Elsevier Ltd on behalf of ISA.

Automated summary

This study focuses on the adaptive control issue of high-order nonlinear systems with odd rational powers, unmodeled dynamics, and non-triangular structure. By employing the adaptive technique, adding a power integrator method, and neural network method, a new adaptive controller is successfully constructed, greatly reducing the use of parameter estimations.