Reset-and-hold control of systems with time delay

Abstract

— Reset control is a kind of hybrid control which is ca pable of overcoming fundamental limitations on the performance intrinsic to linear time invariant (LTI) systems. In this work, we develop a novel parallel control strategy for first order LTI plants with delay based on the proportional-integral plus Clegg integrator (PI+CI) controller, a hybrid extension of the proportional-integral (PI) controller, augmented with a mechanism for keeping its state constant during a given interval of time (reset-and-hold strategy). This strategy is capable of producing an approximation of a flat response which greatly improves the performance in compari son with non-hybrid linear strategies, extending previous results developed for first order systems without delay. An example is developed that showcases the possibilities of this new approach.