Closed Loop Network Servo Control Technique

The combination of traditional control technology and information technology produces networked control system and NCS has been widely applied in control field. In NCS data is transmitted through network so that networked delay will come into being inevitably. If the design of controller can't handle the networked delay effectively, the performance of the system will descend and the system may become unstable. So nowadays the researches of NCS mainly aim at coping with delay problem. It's very meaningful to develop corresponding analysis methods and design theories according to the actual particularity.Based on the linear time-invariant plant, the experimental methods and control strategies are studied. The control technology and experimental technology are combined to develop the design methods and theories in order to improve the performance of the networked control systems.Firstly, the elementary component and speciality are studied in order to analyze comprehend the effect of networded delays in NCS. Furthermore, a series of special problems including time-variant period, data packet dropout and so on are proposed.Secondly, NCS digitized simulation experiment systems are realized. Due to the variety of network environment consistency of experimental condition can't be guaranteed. The NCS digitized simulation experiment plat that can simulate a series of special problems of network such as the data packet dropout and so on is able to solve above problems and help the analysis of NCS.Thirdly, the design methods and control strategies in both certainty control and stochastic control areas. The working of NCS node is improved in order to solve the delay maximum problems in certainty control methods. Through the setting of buffers and application of frequency multiplication sampling, a new working method of networked control system is proposed to compensate the network-induced delay. Moreover, traditional stochastic optimal state feedback contro method can't satisfy the realtime demand because of its complexity of computing. Therefore, the existence of the steady solution of the stochastic Riccati equation in the NCS stochastic optimal control is proposed and proved. The stochastic state feedback control strategy of the mean square stabilizable systems is given based on the above conclusion. The method that can obtain better response and reduce the complexity of algorithm has practical application values.At last, CAN bus is applied to servo control systems to constitute a closed-loop networked control system based on CAN bus. It's absolutely necessarily to design and realize such a system that can help the solution of the practical problems and validation of theories.