Reset control of integrating plus dead time processes

This work develops a tuning method for a reset compensator and an integrating plus dead time system. The reset compensator consists of a proportional integral compensator plus a Clegg integrator (Pl+CI), and is equipped with a variable band resetting law, which allows to reduce the harmful effect of time-delay, and a switching reset ratio that obtains a superior performance in comparison with a well-tuned PI compensator. This work exposes a simple tuning rule for setting all the parameters of the PI+CI compensator with the aim of improving both setpoint tracking and load disturbance rejection. A case study is analyzed by simulation, discussing both performance and robustness of several Pl+CI and PI compensators. Finally, an experiment of liquid level control shows the advantages of the proposed reset compensator. (C) 2015 Elsevier Ltd. All rights reserved.