Fieldbus control system(FCS), which meets the requirement of automation control system for distribution, network and intelligence ,is applied and becoming the hotspot of automation technology. As a typical distributed real-time system, the application of FCS is confined due to the lack of real-time modeling, analysis and scheduling theory. In this dissertation, the author tries to investigate the real-time modeling, scheduling and analysis of FCS, which will set up a good basis for design and realization of applications. Main works and innovations of this dissertation are as follows. 1.The similarly job shop scheduling problem and precedence graph based static real-time models are constructed for periodic tasks of Foundation Feildbus. Static scheduling table, which can meet the constraints of timing, precedence and resource, is solved with genetics and hybrid genetics algorithms and schedulability condition is discussed. 2.The polling server and response performance improved algorithms, which can evaluate the response performance of aperiodic tasks in FF, are put forward. The effect to control performance due to scheduling delay is taken into account. 3.Hybrid tasks real-time scheduling model is constructed for OPC server. The method can improve the processor utilization and response performance of aperiodic tasks with dynamic setting the deadline of aperiodic tasks, and schedulability is analyzed. 4.Fuzzy real-time scheduling model is put forward for real-time database. The structure and parameters of fuzzy scheduler, which can improve performance in the overloaded environments, are designed after considering the uncertain characteristics of tasks' importance and timing. 5.According to the real-time requirement of remote supervise and control system based on Internet, the real-time scheduling model which adapts the closed-loop feedback control of quality of service is constructed. The framework and parameters of controller based on hybrid feedback and self-adaptive switch is designed on the basis of the single-loop control of utilization and miss-ratio. The framework can improve dynamic performance and guarantee static performance.
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