The Design Of Online Monitoring And Faults Diagnosis Of Secondary System Of Digital Traction Substation

With the rapid development of high-speed railway in china,China's high-speed railway has gradually from the construction period into the maintenance period,people are more concerned about the high-speed rail security,stability.With the increase of operation time,the performance of high-speed railway traction power supply equipment will show a downward trend.As the power source of high-speed rail EMU,the safe and reliable operation of traction power supply system is of great significance to the reliable operation of the whole railway system,the operation of the secondary system directly determines the safety and stability of the entire railway power supply system.In order to further improve the reliability of digital traction substation operation,the research on the on-line monitoring and fault diagnosis of the secondary equipment in the substation is of great significance to the design and improvement of the traction power supply system.Digital traction substation is composed of intelligent primary equipment,networked secondary equipment,intelligent substation enables intelligent electronic devices to share information and interoperate.This paper focuses on the problem of on-line monitoring and fault diagnosis of secondary system of digital traction substation,mainly from the following several aspects of the research:First,introduces the digital traction substation secondary system architecture and its characteristics,and the network packet analyzer device are introduced.This paper will use the secondary equipment monitoring data provided by the network packet analyzer to realize the on-line monitoring of the whole secondary system and the monitoring information as the information source of the fault diagnosis.Then according to the demand analysis,design the framework of on-line monitoring and fault diagnosis system for the secondary system of digital traction substation,describe the function of the system and the information source of the system.Based on the secondary device monitoring data provided by the network packet analyzer,using Delphi programming to realize the graphical monitoring interface of secondary equipment,complete on-line monitoring of the entire secondary system.according to monitoring information,through the analysis of the secondary system state information source and evaluation object,the state evaluation index set and the hierarchical analysis model of the secondary system of digital traction substation are established,and then use the fuzzy comprehensive evaluation method to establish the digital traction substation secondary system on-line state evaluation method,make the correct evaluation of the secondary system real-time work status,and according to the evaluation results to develop a reasonable secondary system state maintenance plan.In the digital traction substation secondary system fault diagnosis method,as the secondary system work environment is poor,there are many uncertainties in the process of information collection,transmission and processing,in view of the uncertainty of information acquisition in secondary system fault diagnosis,a fault diagnosis method based on fuzzy Petri net is proposed,according to the characteristics of high-speed railway traction power supply system protection and the composition of fuzzy Petri net and secondary system fuzzy Petri net fault diagnosis rules.a fuzzy Petri net model is established for each element in the form of three layers of reasoning;Using a section of the actual line for fault diagnosis analysis,the results show that the diagnostic method can show all the reasoning path from the starting proposition to the end proposition,in the form of probability given the confidence of each component may fail,can get the correct result.Finally,the software of online monitoring and fault diagnosis system of digital traction substation secondary system is introduced.Through the numerical analysis,it is verified that the user interface of the software is friendly,intuitive and easy to use,and the diagnosis result is correct.