Research On Impact Component Monitoring And Suppression Methods For High-speed Automatic Over-phase System

With the rapid development of high-speed railway, the opening mileage has been 22,000 km at the end of 2016 in China. However, when the high-speed train go through the electric phase-splitter area, multiple arc may be generated and the contact line and bearing cable will be burned. And the overvoltage breakdown of the roof protection gap will cause traction substation tripping accident. It will affect the safe and reliable operation of high-speed train seriously. Therefore, this paper carries out research on the impact component monitoring and suppression method of high-speed train automatic passing phase-splitter system. Reveal the impact of high speed train automatic passing phase-splitter transient process on the impact of vehicle transformers and power grids.The scheme of overvoltage and magnetizing inrush current based on quasi -synchronous device is proposed,which provides the theoretical basis for the safety and reliability design of high speed train and the electromagnetic environment management of power grid.This paper mainly studies as follows:1. The high-speed train traction power supply system and the power supply mode are analyzed, and three kinds of high-speed rail automatic over-phase principle are studied, including the automatic switching system of the ground switch, the automatic passing phase of the vehicle and the automatic switching over the column. The advantages and disadvantages of three high-speed train automatic passing phase-splitter methods are campared and analyzed;2. The mechanism of over-voltage and over-current in the high-speed train is analyzed, including the over-voltage of the transformer, the generation mechanism of the inrush current and the over-voltage mechanism of the neutral section of the electric separation zone. According to the transient process of the vehicle parameters are calculated to establish the sub-closing equivalent circuit which reflects the process of high speed train passing phase-splitter, and the voltage equation is deduced;3, Using Matlab/Simulink for the joint electric separation structure, high speed train and traction power supply network to establish the actual data to reflect the high speed train through the electrical phase of the electromagnetic transient simulation model, and electromagnetic transient simulation, obtained a neutral line overvoltage amplitude and waveform, and derive the overvoltage and magnetizing surge waveform of the vehicle traction transformer;4. The design and manufacture of high speed train automatic passing phase-splitter impact component detection device is used to simulate the opening and closing angle of the high speed train passing phase-splitter process,which includes hardware circuit and human-computer interaction software. Through the experimental study on the factors influencing the over-voltage and the inrush current high speed automatic passing phase-splitter transient shock mechanism of the correctness;5. The circuit characteristics of the high speed train passing phase-splitter are studied, and the over-voltage control measures and the optimization parameters are put forward based on the RC absorber. At the same time, the influence of the initial phase angle of the closing voltage on the overvoltage is also studied, and the scheme of magnetizing inrush current based on automatic quasi-synchronous device is proposed.The experimental results show that the overvoltage of the neutral line is the capacitive line closing oscillation overvoltage, which is closely related to the phase voltage of the contact wire and the phase of the contact line voltage when the pantograph enters the electric separation phase, and the traction carrier itself irrelevant,its amplitude is random. The voltage and current at both ends of the vehicle traction transformer are related to the voltage phase of the contact with the main circuit breaker when closing the operation. The RC absorber, which is optimized for the installation of the pantograph, is equipped with a quasi-synchronous closing control device to effectively suppress the overvoltage and inrush current amplitude.