Study On The Spectroscopic And Electromagnetic Radiation Characteristics Of Pantograph-catenary Arc

The good contact between the pantograph board and the contact line ensures the stable flow of the high-speed railway.Since the speed of high-speed railway increases,the vibration between the pantograph and the catenary intensifies,which leads to the frequent off-line and the frequent occurrence of pantograph arcing.The pantograph-catenary arc plasma,with high energy and high temperature,can seriously ablate the pantograph strip and catenary wire,threating the train safety.In addition,the pantograph arc also releases high intensity and wide band electromagnetic radiation,interfering with the work of train communication equipment and signal system.However,the researches of pantograph arc are mainly focused on monitoring online and electrical parameters measurement,while the analysis of the state parameters and electromagnetic radiation of pantograph arcing are sitll lacking,and unable to quantitatively explore the influences of operation conditions on pantograph arc.Therefore,it is necessary to study the plasma parameters and electromagnetic radiation characteristic of pantograph arc,so as to deeply understand the electrical damage mechanism of pantograph catenary arc.Firstly,this paper is aimed at the research of the internal parameters of pantograph arc plasma.The platform of pantograph-catenary arc optical emission spectrum acquisition was built,based on the principle of emssion spectrum diagnosis,the emission spectrum of pantograph arc was collectted and assigned.According to the characteristics of emssion spectrum,the specific characteristic lines were selected to calculate excitation temperature and electron density of pantograph arc,and the gas temperature was calculated by fitting molecular spectral with software simulation.Through Abel inverse transformation,the spatial distribution characteristics of the plasma parameters of the pantograph were studied.Furthermore,the influences of the current and pantograph-catenary gap on the plasma parameters were explored.Combining spectral diagnosis with infrared images,the variation laws of pantograph arc plasma and electrode temperature during the pantograph lowering process were studied,and the dynamic characteristics of plasma parameters of pantograph catenary arc were verified.This research is conductive to provide accurate data references for simulation models and further reveals the electrical damage mechanism of the pantograph-catenary system.At the same time,with the use of simulation software Ansoft HFSS,fourth order Hilbert antenna model was set up.The influence of antenna wire width,the thickness of the slab and the feed position on the antenna performanc were analyzed.The Hilbert antenna design was optimized for pantograph arc electromagnetic radiation detection.The fourth order Hilbert antenna is realized.The vswr of Hilbert antenna was measured by the vector network analyzer,and was compared with the simulation result.Based on the pantograph arc electromagnetic rad iation test device,electromagnetic radiation and arc voltage and current signal were measured synchronously.The generation mechanism of arc electromagnetic radition was found.The FFT transform of the pantograph arc electromagnetic radiation signal was completed,and the spectrum of electromagnetic radiation characteristics of the pantograph arc was acquired.This research is conductive to realize the miniaturization of arc detection equipment and provides theoretical support and data reference for the establishment of electromagnetic compatibility standards for pantograph-catenary arc.