Research On Electromagnetic Compatibility Risk Of On-board Signaling System In High-speed Railway

As the first choice of transportation,high-speed railway(HSR)plays an important role in domestic travel with fast,comfortable,on-time,affordable and safe advantage.The onboard signaling system is one of the most critical components responsible for operation control in HSR.To ensure the safe,reliable,and efficient operation of the electric multiple units(EMU),the lines,stations,and EMU are efficiently coordinated through control and communication functions of the on-board signaling system.However,the complex electromagnetic(EM)environment of the HSR system has brought a great threat to the on-board signaling system equipment.The on-board signaling system completes the operation and control of the EMU through the communication ports,control ports,and antenna ports distributed in various parts of the EMU.Furthermore,the power dispersion technical characteristics make the interactions between the EM environment and the onboard signaling system equipment more complicated,and the electromagnetic interference(EMI)event has become the focus in the railway electromagnetic compatibility(EMC)domain.According to the EMC theory of the on-board signaling system in HSR system,the extended risk model based on the “disturbance source-coupling-equipment” EMC principle are firstly built to solve the disadvantages of the lack of consideration of the EMC part in traditional risk model method,and the EMC risk factors are determined.Then,combined with the operation scenarios and structural layout of the EMU,the characteristics of the off-line EM disturbance on the roof,the current EM disturbance in the vehicle body,and the traction drive system EM disturbance at bottom of the EMU are studied respectively.Then,a network-based method for analyzing the EMI characteristics of the on-board signaling system is built to research the EMI characteristics of different subsystems,modules,or components.Finally,the EMC risk level of the on-board signaling system is achieved based on the cloud model and the Cube risk assessment model.According to the research of the thesis,the innovations are as follows:(1)An EMC risk analysis method base on operating scenarios in HSR is proposed.According to the different operating conditions of the EMU,the risk model is expanded to cover EMC elements that are not included in the traditional risk model.(2)The characteristics of the EM disturbance source from the off-line discharge between the pantograph and catenary are studied,and the radiation coupling and conduction coupling model of the off-line EM disturbance are established based on the traveling wave antenna and transmission line theory.Besides,a measurement method of the off-line EM disturbance in the viaduct scenario is proposed.This method can avoid the influence of viaducts on the results and improve the applicability of the measurement method in Chinese HSR.(3)A network-based analysis method of EMI characteristics is proposed for the on-board signaling system in HSR.To abstractly description of the EM disturbance source and the on-board signaling system in EMU,the EMC elements are abstracted as nodes and edges in the model based on the structure and layout of the EMU and signaling equipment.Thus,the method solves the problem that the EMC risk model is difficult to systematically express the EMI paths facing such a complex system.(4)An EMC risk assessment model for the on-board signaling system based on the cloud model and Cube model is proposed.Combining the characteristics of EM disturbance sources that cause EMI to the on-board signaling system,the EMC risk level is determined by the assessment model based on the EMI path in different operating scenarios.The problem that laboratory test is difficult to deal with the uncertainty of the EMC problem in actual operation is solved.The above results have certain theoretical and engineering practical value for improving the EMC of the on-board signaling equipment in the HSR system.Moreover,it can provide useful help for the EMC theoretical research,EMC design,and the system EMC management of the electrical and electronic equipment in HSR.