Research On Traveling Wave Position Sensing Technology Of Non-contact Magnetic Induction Fault

The electrified railway system in China has become increasingly sophisticated,not only ranking first in terms of mileage,but also reaching the world's leading level in terms of technical level and construction quality.The electrified traction network system is one of the core technologies of high-speed railways.Transmission lines are the basis of trains' power supply.Once a line fails,it will bring huge security risks to the normal operation of the railway system.Traveling wave ranging method has the advantages of stable traveling wave speed,close to the speed of light,and is free of system parameters,transition resistance,system operation mode,and line load.This article will focus on the research of high-precision traveling wave senso r technology in traveling wave fault location technology,and will study a non-contact magnetic induction traveling wave sensor.The main research contents of this paper are divided into:(1)Analysis of the generation,propagation process and propagation mechanism of traveling wave characteristics in the fault traveling wave,theoretical verification of the working principle of electromagnetic wave based traveling wave sensor.(2)The core is an important part of the sensor.How to select the core material has great influence on the stability of the sensor.By studying the magnetic properties of the magnetic core,the loss mechanism of the sensor during operation is determined,a mathematical model of sensor loss is established,and a method of reducing the loss is obtained.(3)Determine the core material and shape,and establish a circuit model for the influence of the number of turns on the DC resistance and distributed capacitance of the sensor.With the core determined,a parameter optimization method was proposed.According to the parameters of the sensor,a simulation model of the sensor is established.The influence of copper turns,copper wire diameter and core permeability on sensor performance was verified by simulation and experiment.(4)Based on theoretical analysis results and experimental data,the development of noncontact magnetic induction traveling wave sensor is completed.To design a good sensor,simulated field test,and analyze the data obtained from tests,the sensor is obtained under different fault response frequency between 50.1 KHz to 50 MHz.