Robust full order anti-windup compensator design for a class of cascade control systems using LMIs

Abstract

This paper presents with some new perspective the design of anti-windup compensator (AWC) for cascade control systems in the face of saturation nonlinearity fallen due to plant input constraint supplemented by plant uncertainty. Thus the developed full order AWC incorporating robustness keeps the closed-loop cascade system response stable at saturation and uncertainty. The performance of robust AWC in cascade control is also observed considering its pole position in bringing the plant to its steady state. Pole position in AWC design, results in better control of steady state settling time of plant output. Based on diagonal quadratic Lyapunov stability, reduction of \({\fancyscript{L}_2}\) norm, sector bound, multi-loop compensation, performance and robustness improvement, linear matrix inequalities are derived for dynamic AWC and applied on constrained cascade control plants. Technique is explicitly demonstrated on industrial constrained cascade control processes to validate the design.