Indirect adaptive control for systems with input rate saturation

Abstract

An indirect adaptive control design with anti-windup augmentation for stable systems subject to input magnitude saturation is extended to address systems with significant input rate constraints. We use the method of interpreting the dynamics of the actuator, the plant and the unconstrained controller such that either the Linear Matrix Inequality (LMI) or the Riccati based anti-windup compensator design approaches for systems with input magnitude limitations can be exploited. We combine the control structure including the anti-windup compensator with an adaptive law and show that the stable performance of the nominal design is preserved in the presence of input rate saturation despite the unknown plant parameters. The proposed indirect adaptive control design methodology can be employed to recover the unconstrained tracking performance of plants with large parametric uncertainties by suppressing the adverse effects of dominant input rate saturation. ©2008 AACC.