Analysis and Synthesis of NCSs with Random Feedback Delay

Abstract

Recently, there are some preliminary results on designing networked controllers for compensating random time-delay and data dropout, see for example, [116, 120, 119], where the random network delay in the forward channel in NCS has been studied. But, the random network delay in the feedback channel makes the control design and stability analysis much more difficult. This chapter proposes a predictive control scheme for networked control systems with random time delay in the feedback channel and also provides analytical stability criteria of closed-loop networked predictive control systems. In order to compensate for the network transmission delay, a network delay compensator is proposed. The predicted sequences are sent to the actuator in a package. The networked predictive controller chooses the latest input value from the predicted sequences available on the actuator side. Under this control scheme, the closed-loop system will be a switched linear system. The theory of switched systems can be used to judge whether the closed-loop system with random time-delay is stable.