Research On Regenerative Energy Feed Technology And Device Application In Urban Rail Transit

With a booming development of national urban subway since 2008,its industry has improved rapidly.As the first subway line in Kunming,the Kunming Rail Transit Line 6 project was opened in 2011.By 2019,Kunming Metro has opened four lines,including the first phase of Line 1 and Chenggong Branch Line,the first phrase of Line 2,Line 3 and the first phrase of Line 6.The length of the line has reached 88.7 km.There are 57 stations,including two transfer stations.With the preliminary formation of metro network and the increase of operation lines,how to effectively control operation costs has became the core of management.Electric energy is the power of each metro professional equipment and system,so how to use electric energy more green and efficient and how to use and upgrade the power of Metro transportation are the the most popular leading edge and application.This paper aims at studying the traction and braking energy consumption of electric passenger trains in metro power supply system,discussing the braking characteristics of AC electric passenger trains and the generation of regenerative braking electric energy.Because the distance between urban subway stations is very short and the stations are relatively dense,meanwhile adding the train with frequent running and parking in the process of train operation,the considerable regenerative braking energy is generated in the electric braking of trains.The current DC traction equipment uses diode single-way rectifier,so the energy generated by regenerative braking of trains can not be fed back to the medium voltage AC network side for secondary use.The solution is mostly using the braking system to transform electric energy into the form of thermal energy release,which increases the pressure and load consumption of station environmental control and ventilation equipments.For the utilization of regenerative braking energy,this paper analyses the advantages and disadvantages of nine kinds(three types)of regenerative braking energy utilization schemes at home and abroad.Finally,according to the actual engineering needs of Kunming Metro Line 3,a 35 k V medium voltage system feedback scheme is selected.Its simulation model is established through MATLAB/Simulink software.The simulation results show that the feedback effect of voltage control for 35 k V medium voltage system is good,and the function and effect of this scheme are demonstrated.Finally,according to the actual situation of Kunming Metro Line 3,the paper makes the overall research on the practical application of the regenerative energy feedback equipment project,designing and analysing the technical requirements and control requests of the regenerative energy feedback equipment.The data analysis of the actual engineering application effect of the final project verifies the good effect of the feedback scheme of 35 k V medium voltage system,as well as the experience of the regenerative energy feedback equipments is summarized by a case analysis in operation.