Management And Analysis Of Measured Data Of Electric Power Quality Of Electrified Railway

Electrified railway has gradually become the main way of passenger and freight railway transportation in the middle and long distance due to its advantages of strong transportation capacity,high energy utilization rate and environmental friendliness,and it has been widely used throughout the world.As the power source of electrified railway traction load,the traction power supply system directly affects the safe operation of traction trains and the power quality of the power system.At present,the measured data is an important tool for analyzing and studying the power quality of electrified railway.However,due to the fact that complete data centers of power quality for electrified railway are rare,the power quality data of electrified railway is scattered and low in utilization.The efficient management,analysis and utilization of such data is of great significance to the management of power quality of electrified railway and the operation and management of the power grid.In the aspect of analysis of power quality data of electrified railway,this paper conducts research on harmonic standard of power quality and analysis methods of power quality data.In the study of harmonic standard of power quality,based on the power quality data of the high-voltage side of a typical traction substation on the Beijing-Shanghai line,the characteristics of power quality of the substation connected to the power grid are analyzed and summarized.At the same time,it discusses the harmonic standard of power quality according to its harmonic characteristics,and points out the shortcomings of the current harmonic standard in the distribution of harmonic current limit.Combined with the harmonic current data on the high-voltage side of the substation,the current harmonic national standard and the newly revised public network harmonic standard(consultation draft)are compared to study the characteristics of harmonic current limit and their applicability to electrified railway.In the study of analysis methods of power quality data.Firstly,a comprehensive evaluation method of power quality for traction substations' classification management is proposed.Combined with the K-means clustering algorithm,this scheme implements the grading evaluation and classification management of the power quality of traction substations,and proposes targeted improvement measures of power quality for traction substations with different clustering levels.Secondly,harmonic impedance in the harmonic propagation circuit is identified and studied using the transfer law of the harmonic current of the two power supply arms on the traction side.The dynamic model test platform verifies the effectiveness of the proposed method.The results show that the proposed method can effectively compensate the error of the harmonic impedance of the traction network system,and the identification result is accurate and reliable.Finally,combined with the proposed schemes,the idea of the development of auxiliary decisionmaking software for analysis and governance of power quality of electrified railway is studied.In the aspect of management of power quality data of electrified railway,this paper completes the design of the database and the file management system of the power quality data of the electrified railway.At the same time,combined with the analysis technology of big data,a set of management and analysis platform for power quality data of electrified railway based on B/S architecture is developed.The platform includes functions such as user management,file management,database reports,oscilloscope file analysis,and comprehensive evaluation of power quality in substations,and provide valuable data information materials for researchers.