Model Building And Characteristic Analysis Of Conduction Interference For Traction Converter

In recent years,with the rapid development of urban rail transit industry,the status of urban rail transit in public transportation and passenger flow scale have been rising steadily,which has laid a good foundation for the transformation of China’s urban rail transit from high-speed development to high-quality development during the 14 th Five-Year Plan period.Rail transit vehicles installed with high power traction converter device,with the rapid development of modern power electronic technology,traction converters to high frequency,large capacity,modular and function integration in the direction of the development of high power switching devices can cause converters have serious electromagnetic interference,traction converter electromagnetic interference will not only affect the traction converter system itself,It will also pose a threat to the surrounding system,and even cause the EMC test of the entire train to fail.The subsequent rectification will not only cost a lot of manpower and material resources,but also cause the delay of the train rolling off the line.Electromagnetic interference(EMI)mainly affects peripheral equipment and environment through conduction and radiation,of which conducting interference is the fundamental one.It is particularly important to study the generation mechanism,propagation path and characteristics of conducting interference to improve the EMC characteristics of converters.This paper takes a type metro traction converters as the research object,based on the analysis on the mechanism of the conducted interference,the conducted interference model was established,and designed the conducted interference experiment,analyzes the characteristics of the conducted interference of traction converters,further analysis the influence of key parameters on the conducted interference,and reduce the advice of the conducted interference traction converters is presented.Firstly,based on the analysis of the working principle of traction converter and the establishment of its electrical model,the generation mechanism of conducted interference is studied,and the switching characteristics of IGBT are analyzed.It is clarified that the dv/dt of IGBT switch plays a decisive role in the intensity of conducted interference.Based on the analysis of the key structure of the traction converter,the conduction interference path is determined.Then,a characteristic model of IGBT was established using ANSYS Simplorer software,and the characteristics of power cable,stacked bus,support capacitance,common mode capacitance,IGBT module and radiator parasitic capacitance,and reactor were analyzed by using electromagnetic field theory.The parasitic parameters were extracted by calculation method or ANSYS Q3 D software.Complete the modeling of the device.On this basis,the system-level conduction interference model of traction converter is constructed.Finally,in order to verify the accuracy of the electric model,the electrical experiment of the traction converter was designed and carried out.In order to verify the accuracy of the conduction interference model,the conduction interference experiment of traction converter was designed and carried out,and the DC side common mode signal,differential mode signal and IGBT voltage waveform were tested.Then,the parasitic capacitance between IGBT module and radiator and the IGBT gate resistance which affect the common mode conduction interference characteristics are simulated and numerically analyzed.On this basis,some reasonable suggestions for the design of traction converter are put forward.