ADRC-based Network Control System Analysis And Design

As industrial production continues to expand, it is becoming increasingly difficult for the traditional motion control to meet the practical demand with growing security requirements for the manufacturing process. The development of modern network control technology, makes the research of network control system has the new breakthrough, to solve the defects of traditional control method opens up a new way. Network control system by using communication network to connect the sensors, controllers and actuators together, compared with the traditional point-to-point control system has many advantages. Network control system bring a variety of convenience, due to the intervention of network also bring a series of corresponding problems, such as network time delay, packet dropout, temporal disorders, and network scheduling problems, especially the time delay and data packet dropout problems become one of the difficulties of network control system research.In this thesis, for time delay and data packet dropout two problems that exist in the network control system, we propose a compensation method based on the ADRC(Active Disturbance Rejection Control) technique to achieve stabilization for the networked system. The main research contents are listed as follows:1. A mathematical model is used to describe a system whose actuating channel and sensing channel subject to time-varying short network-induced delay, where the time-varying delay is regarded as an uncertainty. An ADRC strategy is appealed for compensating the uncertainty by dynamic linearization, achieved the time-varying delay real-time compensate and system stability control.2. A mathematical model with the actuating channel subject to data dropout,and bernoulli method is described as random packet dropout process, is established by considering the effects of the data dropout as disturbances. An ADRC strategy is appealed for compensating the disturbances via linearization and stabilization for the NCS under consideration is thus achieved.3. In order to verify the validity of the designed controller, build up simulation platform by TrueTime toolbox, analysis the simulation with time delay, packet dropout, and both time delay and packet dropout three cases in network control system. Compared with Smith predictor method and generalized predictive method, it is verified that the ADRC has high control accuracy, fast response, anti-interference performance and so on.