Modeling, Analysis And Design Of Hybrid Systems Based On Petri Nets

All traditional control area comes down to hybrid systems. The behaviors of hybrid systems are determined by interacting with continuous systems and discrete event systems. In the latest 10 years, the research of hybrid systems arouses the broad interests among the scholars of control area and computer area. They have acquired many research productions. It is very important for us to describe the dynamic behaviors of hybrid systems accurately with model. Many methods are used to model hybrid systems. Petri Nets are one of the methods in common use.Petri Nets model of hybrid systems is generalized 3 types and discussed as follows: 1) Embed the dynamics of continuous subsystems in discrete event systems, then model it with Petri Nets. This modeling method depends on the partitions of state space. This paper establishes the exchange relation between induced systems of hybrid systems and Petri Nets model, then gains Petri Nets model which reflects aggregate properties of hybrid systems. 2) Import discrete transition to continuous systems and describe the switch logic of continuous subsystems of hybrid systems with Petri Nets, on the basis of this, utilizing basic cycle of its occurrence nets to analyze the controllability of hybrid systems and study its use of simplifying computation. 3) Consider the interactions between continuous dynamics and discrete dynamics, then model discrete dynamics with ordinary Petri Nets and model continuous dynamics with continuous Petri Nets. Namely use hybrid Petri Nets to specify hybrid characteristic of hybrid systems.Based on the Petri Nets model of hybrid systems, this paper discusses the implementation of supervisory controller of hybrid systems through the example of dual integral system. Finally probes into the design of automated drive vehicle system and builds the Petri Nets model of drive mode decision. Then describes the model in ABEL-HDL. The source file is compiled, simulated and fit design through Lattice EDA software-ispDesign EXPERT, at last the JED file is downloaded in the chip ispLSI1032E. Thus the design and implementation method of concurrent controller of hybrid systems is presented.