Tuning of discrete-time PID controllers in sensor network based control systems

This paper studies the tuning of discrete-time PID controllers for processes that are observed with sensor networks. It is assumed that a wireless sensor network gathers information from the process. The characteristics of sensor networks cause varying delays to the measurements, and the tuning of a discrete-time PID controller is studied in this framework. Controller tuning rules are developed by optimizing the performance of the closed-loop system with respect to certain cost criteria. Constrained optimization is used for finding optimal controller parameters and to guarantee the desired gain and phase margins and stability of the system even if the delay varies.