Modeling Of Colored Petri Net Based On UML And Its Application In CTCS-3

With the leaping development of China Railway and speed increasing of train, the traditional train control mode that drivers operate trains according to the signal aspects can not ensure the safe train operation. So it is needed to equip train control system (CTCS). Because of the complexity of CTCS, it can not carry on the work of interoperability testing and performance evaluation on parts of CTCS. So it must study the theory of model and simulation of CTCS. It is great significance to solve practical problems of railway construction, foster self-innovation capacity and master key technologies of CTCS.The thesis chooses modeling methof of colored Petri net based on UML to study the modeling and simulation of CTCS-3. As a universal graphical modeling language, UML cannot make formal analysis and verification to the model of the system for lacking of exactly semantic description. However, Petri Net has a set of theoretical analytic methods and tools and Petri Net model can be directly converted from UML diagrams to be analyzed and verified. After analyzing the advantages and disadvantages of the UML modeling diagrams, the thesis chooses colored Petri net as the formal specification to convert UML model diagrams. The limitation of setting up models to system directly by formal methods is avoided. Furthermore it decreases the difficulty of using formal methods, improves the extendibility of formal methods and remedies the model analysis and verification means of UML.The thesis aims at the sequence diagram and state diagram which are dynamic models of UML to study on the Colored Petri net modeling methods of them on the basis of other researches. Because of the limit expressive ability of UML sequence diagram, the thesis adopts extend method of sequence diagram which enhances the modeling ability of the sequence diagram. Then the thesis mainly studies on the transformation method of interactin segments which can transfer sequence diagram to Colored Petri net. The state diagram can describe the process of the state transition with driving of events in the object's life cycle. The thesis improves rules which transform UML state diagram to sub model of object Colored Petri net, algorithm of colset, and algorithm which maps the sub models of object Colored Petri net into the object Colored Petri net. In the end, the thesis simples the transformed models of UML sequence diagram and state diagram. With the application of the two transformation methods in CTCS-3, the thesis designs communication sequence diagram between onboard and radio block center of CTCS-3. According to the transformation method of sequence diagram, the thesis transfers the sequence diagrams to hierarchical Colored Petri net. The thesis designs the state diagrams of onboard, GSM-R and radio block center on the condition of train normal operation and transfers them to sub models of object Colored Petri net. According to message transmission of onboard, GSM-R and radio block center, the thesis obtains the model of object Colored Petri net. With CPN Tools, the thesis simulates the obtained models and analyzes boundedness properties, dead markings and so on, and verifies the correctness of the models.