Research Of Control And Scheduling Co-design Methods For Networked Control System

With the rapid development of communication technology, computer technology and control technology, networked control system (NCS) has been the research focus of the control field. NCS is the comprehensive application of communication technology and control system, so the combination of the two brings many new problems, such as network-induced delay, data pack loss, type of drive and time synchronization and so on. The traditional control theories can not satisfy the requirements of the NCS. So scholars have to evaluate and set up new control theories and control mathods of NCS again.At present the main theories of NCS are researched from control, network scheduling, control and scheduling co-design perspective. This thesis designs feedback scheduler in terms of network scheduling, control and scheduling co-design for multi-loop control system. This feedback scheduler can distribute network bandwidth resources reasonably to optimize network-induced delay. So the performance of NCS can be improved to some extent.Firstly, the existing basic problems, the reaearch status of NCS are introduced. The structure and function of NCS’s simulation toobox Truetime are also presented. Secondly, in the condition of the network bandwidth limited, considering the system output errors, the change rate of system output errors and the dynamic compensation weights of different control circuits, this thesis puts forward a priority configuration stategy based on fuzzy feedback scheduling using dynamic weight compensation method. Then a fuzzy feedback scheduler is designed to adgust the priorities of different control circuits. The simulation results prove the effectiveness of the method presented in this thesis. Thirdly, from the perspective of control and scheduling co-design, on the basis of previous research this thesis designs a feedback scheduler based on variable sampling period. This method also considers dynamic compensation weights of different control circuits. Next this thesis sets the upper and lower bounds of the sampling period. Finally in order to solve the conflict when the information transmitting on network. Combining fuzzy feedback scheduler in chapter three, this thesis presents variable sampling period and priority of fuzzy feedback co-design mathod to improve the quality of NCS.