Control System, Based On The Model Of The Network Input Multi-rate Sampling

With the rapid development of the computer and network technology, digital control and networked control are the considerable choice in the modern industry control. The modeling, analysis and control of the model-based networked control systems (NCSs) with multi-rate input sampling are studied in this dissertation.Firstly, the development and some features specific to NCSs are introduced. Some basic problems and recent advances in research are discussed in detail.Secondly, the modeling, stability analysis and controller design on model-based state feedback networked control systems are studied. The transmission of data packet in NCSs is analyzed and the basic concept of model-based structure methodology is introduced in this thesis. The description of network delays including characteristics and effects are also covered and the uniformed mathematic models for NCSs with four different structures are derived. Furthermore, the controller basing on state prediction and compensating time delay is designed. Sufficient and necessary stability conditions for systems with different transmission policies such as perfect transmissions, delayed transmissions and time-varying transmissions are obtained as simple eigenvalue tests of certain test matrices. And in the end, effects of model error over maximum communication interval are analyzed. Numerical examples show the feasibility and efficiency of the proposed methods.Thirdly, the modeling, analysis and control of the model-based output feedback networked control systems are studied. The mathematic models of systems with perfect transmissions and delayed transmissions are developed. The predicting controller for compensating time delay is designed and the sufficient and necessary conditions for the global exponential stability are derived. The effects of model error are given. The simulation results show the proposed controllers are right and effective.Finally, the research conclusions are presented. The innovative ideas and the remaining problems that need further research of the model-based networked control systems (NCSs) with multi-rate input sampling are pointed out in this thesis.