Robust Control

Module code: EG7015

This module is concerned with the design of practical feedback controllers. Feedback is used in a control system to stabilise an unstable plant or process and to reduce the sensitivity of the system to signal uncertainty (disturbances and noise) and model uncertainty (dynamic perturbations). If the performance specifications are achieved in the presence of the expected uncertainties, then the control is said to be robust. We will re-examine the classical approach to robust control based on loop shaping and the Nyquist stability criterion; and we will present the latest (H-infinity) methods and tools for loop-shaping control and robust stabilisation. This module will also describe the inherent limitations to performance. The treatment will be mainly for scalar (single-input, single-output) systems but the extension to multivariable (multi-input, multi-output) systems will also be discussed. The principles of the module are applied extensively with the use of the software Matlab.