Modeling And Simulation Of Interlocking Logic Based On Scade

With the rapid development of the economy in China, large crowds of people move into cities, making traffic jam more and more serious. Urban rail transit is becoming the first choice for large and medium-sized cities to solve congestion problems, with the advantages of faster speed, lager capacity, more comfortable and less pollution. CBTC technology came into being under this background, and it becomes the preferred scheme of urban rail transit signal system gradually.As an important part of CBTC system, interlocking system plays an important role for traffic safety. The safety level of interlocking system is high, it is very necessary to use high safety software to develop interlocking system. High security application development environment SCADE provides a completely model based development solution for software developers with less development cost, lower development risk and shorter time.One of the interlocking areas in Zhengzhou metro line one was taken as the analysis object, SCADE was used to model and validate for the main functions of the interlocking. Research situation of interlocking system and its logic modeling at home and abroad was discussed. Main structure of CBTC and function of the subsystem was illustrated. Then basic theory of SCADE was studied. Data flow diagram method and safe state machine method which are two kinds of modeling methods based on synchronous programming theory were explored. Modeling mechanism, characteristics and the applicable objects of semantic model were analyzed. The main content of interlocking and the information transmit between interlock system and other systems were studied. Interlocking system is mainly divided into four parts, which were switch module, route module, signal module and unlocking module. Using the method of data flow diagram in SCADE, logic of interlocking system was designed and modeling of the whole system was finished.Simulation and validation of main modules was done with simulator and validator of SCADE finally, ensuring the security of the model. The code generator of KCG was used to generate the C code automatically for the model. Research and analysis of interlocking system were carried out. Development of interlocking system with SCADE meets the high safety requirements of interlocking system. SCADE has broad application prospects in the development of interlocking software.