Optimization Method For Networked Control System Based On Scheduling

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 optimization methods for networked control system (NCS) based on scheduling are studied in this thesis.Firstly, the development and some features specific to NCS are introduced. Some basic problems and recent advances in research are discussed in detail.Secondly, the scheduling algorithms of the periodic task of NCS are studied. The effect of network induced delay to control system performance is analyzed. And then, considering CSMA protocol and token-type protocol, the scheduling algorithm based on time window and jitter-dependent optimal algorithm are studied separately. In the end, simulation studies are performed to show that the network utilization ratio is improved and the system dynamic performance can be implemented by satisfying the system delay requirements and scheduling sampling period and intersample efficiently.Thirdly, the schedule strategy of the aperiodic task of NCS is studied. A task model for NCS is presented and the schedulability of task set is analyzed. And then, a scheduling algorithm is proposed according to the principles of RMS algorithm and a example is given at the same time. The result shows that the algorithm schedules periodic and aperiodic tasks in the system in such a way that all of their constraints are satisfied and therefore realizes predictable scheduling of aperiodic tasks.Finally, the research conclusions are presented and the remaining problems that need further research of NCS are pointed out in this thesis.