PID controller design for networked control systems

When PID controllers receive the sensor information or transmit its outputs through a communication network, its parameters are difficult to tune using classical PID tuning methods. This is due to stochastic delays introduced by the network in the feedback loop. This paper proposes a design method to compensate the effects of this delay using a constrained optimization to find the PID parameters. The design is based on a polytopic description of the system, which can be formulated using a pdf distribution of the delay. Simulation results are presented to demonstrate the performance of the proposed method.