Design Of Fault Diagnosis System For Locomotive Based On Dynamic Fault Tree Analysis And Sensor Network

With the rapid development of heavy haul railway freight locomotives in China,the malfunction rate and accident rate of locomotives are also rising,the importance of locomotive fault diagnosis technology is becoming more and more prominent.In this thesis,based on the dynamic fault tree algorithm and distributed sensor network,the fault diagnosis system for SS4 B locomotive is designed,and the fault mode of locomotive is analyzed.Moreover,the position of sensors is identified,then designing and selecting the circuit of the hardware part of the system,putting forward the dynamic fault tree analysis algorithm,and realizes it through C# programming.Finally,the theory in the design and the whole system is modeled and simulated to verify the feasibility.Finally,in order to verify the feasibility this thesis modeled and simulated the theory and the whole system of the design.First,according to the actual situation of the locomotive,this thesis designed the hardware of the diagnosis system into four parts,the sensor network,distributed sensor node,data detection terminal and intelligent malfunction terminal.Analyzes the structure and working principle of the main and auxiliary circuits of SS4 B locomotive,and further analyze the specific fault modes of the main and auxiliary circuits and the air brake system.What's more,in terms of the important fault mode of locomotive,the layout positions of 9 voltage sensors and 23 current sensors are determined,and the layout reasons are analyzed.Second,this thesis designed the hardware of the system.The topology of sensor network is selected.The interface of sensor network,the hardware circuits of analog and digital sensor nodes are designed.Furthermore,this thesis introduced the functions of each board of data detection terminal,and completed the selection of intelligent fault diagnosis terminal.In terms of related software,the communication protocol,transmission data content and congestion control algorithm of the network are studied,the filtering algorithm of the sensor node is researched and designed,and the software flow of each node and terminal is designed.Thirdly,on the basis of fault tree analysis,this thesis proposed the dynamic fault tree analysis method that based on sensor information,which can simplify the fault reason obtained by fault tree analysis according to the data collected by the sensor at the fault location.At last,this thesis modeled and simulated the digital filter and congestion control algorithm of the network.After compiled the diagnosis software that can implement the dynamic fault tree analysis algorithm by C#,it is verified and analysed.On the above basis,the joint modeling and Simulation of sensor filtering,network data transmission and fault cause diagnosis are completed to verify the feasibility of the fault diagnosis system.There are 113 figures,16 tables and 79 references in this thesis.