Hybrid Petri Net Theory In The Application Of The Train Operation Dispatching

The railway transportation is a complex giant project. The system of trainoperation and dispatch plays a great important role in this project, as well asmany other factors, including well organized railway lines, well performedrailway vehicles, and well designed control systems and equipments, all theseissues work together to contribute to a safe, orderly and efficient project. Forthis reason, many institutes are engaged in the work of train operation anddispatch at right now.In this thesis, the scientific theory and modeling method of Petri net areimplanted into the base of train operation and dispatch, a new concept of hybridPetri net (HPN) is then developed, and it is employed in the modeling of trainoperation and dispatch, the characters of this new modeling are presented aswell. Besides, a simulation software named CPN Tools is used to verify thisnew modeling. Overall, the contents in this thesis cover the following areas:（1）Brief introduction of the background of train operation and dispatch,including the research status in this field within and without China. Furthermore,the significance and feasibility of Petri net are introduced. （2）The scientific theory and modeling method of Petri net are discussed,which include the definition, properties and rules of the Petri net. Additionally,some extended Petri nets are given here.（3）Based on the analysis of train operation and dispatch, a formalizeddefinition of the HPN is put forward regarding the hybrid property in the systemof train operation and dispatch. It means the railway vehicles are generallyregarded as tokens in continued places, and the railway stations are seemed astokens in discrete places. A new modeling of train operation and dispatch isdeveloped in accordance with the HPN, and the analyzing method of Petri net isapplied in this new modeling. Finally it is found that the new modeling is ofstructural boundedness, partial conservativeness, and active discreteness, itproves this new modeling to be theoretically true.（4）The CPN Tools software is then used to verify this new modeling. Theresults show that each transition is triggered in succession which is a symbol oflogical correctness. Meanwhile an analysis of some characters in this newmodeling is proceeded via the state space report. And the results support the ideathat this new modeling is of correctness and feasibility.