Research On Harmonic Impedance Frequence Characteristic Measurement Of Traction Power Supply System

With the rapid development of China's high-speed railway,the safety and stability operation of traction power supply system(TPSS)in a huge challenge.The harmonic resonance and harmonic instability accidents have occurred occasionally caused by the shared impedance characteristics are not matching of Electric Multiple Units(EMUs)and traction network.One of the key to solve the above problem is to realize the precise measurement of TPSS.Therefore,based on the measurement methods of harmonic impedance frequency characteristics in high-speed railway TPSS,this paper will conduct research mainly from the aspect of methods overview,simulation analysis,experiment verification.This paper is as follows:Firstly,this paper summarized three kinds of measurement process of the harmonic impedance frequency characteristics measuring methods in TPSS from the basic principle of the measuring methods.Which has laid a good foundation for the following simulation analysis.Secondly,based on MATLAB/Simulink platform,the simulation model TPSS has been built.Using three kinds of measurement methods to test the system harmonic impedance frequency characteristics,in this paper,the measuring accuracy and economy index have been contrasted,and through the comprehensive comparison,found that harmonic current injection method is more reasonable.Thirdly,based on harmonic current injection method,the harmonic impedance frequency characteristics measurement precision has been analyzed of background harmonic and noise signal in TPSS,the simulation results verified the applicability and reliability of the measurement method.Lastly,construct the TPSS simulation platform.,using double resonance peak circuit to simulate the TPSS,and constructing harmonic impedance frequency characteristic test platform in the laboratory,collecting a large number of measured data,the measured results with the theoretical calculation results were analyzed,which verify the effectiveness of harmonic current injection method furtherly.Finally,the research content of this article has been summarized,and aiming at the shortcomings of the existing in the research process and the next step of research is prospected.