Research On Dynamic Load Modeling And Application Of High-speed Railway Traction Substation Based On Field Measurement

The China railway consumed 78.726 billion k Wh in 2021,which is the most considerable single load of the State Grid.And its accurate prediction is of great significance in saving railway operating costs and promoting economic dispatch of the power system.However,the traction load of high-speed railways(HSRs)is large and fluctuates violently,which brings many challenges to its accurate prediction: 1)There are many types of Electrical Multiple Units(EMUs),whose traction transmission characteristics and load characteristics are different,which leads to the difficulty of accurate simulation of its dynamic operation process due to frequent switching of conditions;2)Frequent adjustment of the running operation organization lead to dramatic changes of the number and passing time of EMUs in the power supply section of the traction substation.In response to above technical challenges,this paper analyzes the dynamic load characteristics of HSRs traction substations based on theoretical analysis and a large number of measured data.Besides,considering the train timetable,the thesis researches the dynamic load modeling method of EMUs interval operation process and the load forecast method of HSRs traction substation based on the measured data.The main research contents are as follows:(1)Combined with the operation discipline of China HSRs traction power supply system(TPSS),the thesis analyzed the dynamic load composition of the traction substation.Besides,the thesis analyzed the dynamic load characteristics of the traction side bus,based on the field measured data.Combined with the operation mechanism of the EMUs and the traction calculation model,the thesis analyzed the dynamic load characteristics of EMUs during section operation,and summarized the key factors that affect the dynamic load during section operation,including EMUs model,number of groups,up/down conditions,and stop situation.Applying the statistical indicators(such as power,electricity etc.),the thesis established the dynamic traction load characteristic index system of EMUs.(2)According to the non-intrusive load monitoring method,the thesis studied the method of extracting the dynamic load sequence of the EMUs based on the window state,and extracted the dynamic load of each EMU during the interval operation of each EMUs from the dynamic load of the traction substation’s traction bus.According to the dynamic load characteristic indicators(including maximum load,traction power,regenerative power,etc.)of the EMUs’ section operation process,the thesis realized the identification of the EMUs’ section operation process,based on the support vector machine classification method.On this basis of above analysis,for the difference in the actual running time of the same EMUs section operation process caused by the random factors,the thesis studied the dynamic load modeling method of the EMUs based on the DTW and Mean-shift method,and established the dynamic load model of the EMUs section operation process.Finally,the correctness of the modeling method was verified through the case analysis,and the dynamic load model library during the interval operation of the EMUs was established.(3)Combined with the information(such as EMUs model,operation time,stop situation etc.)provided by the train timetable and the dynamic load model library,the thesis studied the dynamic load prediction modeling method of the traction substation.Finally,the thesis conducted a case analysis,which predicted the dynamic traction load of the traction substation after the adjustment of the driving operation diagram.The comparative analysis results showed that the errors of the characteristic indicators of the dynamic traction load were within 10%,which meets the requirements of the traction load prediction accuracy.(4)Based on the MATLAB APP Designer platform,the thesis developed the dynamic traction load prediction software of the high-speed railway traction substation.The architecture of the dynamic load forecasting software for high-speed railway traction substations is analyzed,and the basic functions of the software are shown in detail,including the import of measured data,dynamic load modeling,dynamic load forecasting,and electricity metering.Finally,the research content of this paper is summarized,and the future research is prospected by analyzing the origin of the error.