Robust gain-scheduled Smith PID controllers for second order LPV systems with time varying delay

Abstract

In this paper, a new approach to design a robust gain scheduled linear parameter varying (LPV) PID controller with pole placement constraints (through LMI regions) is proposed for LPV systems with second order structure and time-varying delay. The controller structure includes a Smith predictor, real time estimated parameters that schedule the controller and Smith predictor (using the known part of the delay) and unstructured dynamic uncertainty which covers the delay uncertainty. Finally, the proposed control technique is validated in a real case study based on a piece of a sewer system.