Research On The Dynamic Current-carrying Temperature Rise Characteristics Of Novel Rotatable Pantograph Of High-speed Train

With the rapid development of our country’s economy,remarkable achievements have been made in the process of domestic urbanization.As a major strategic support for our country’s economic development,high-speed railway lines have a total running mileage of 38,000 kilometers and a maximum running speed of 350km/h.Higher running speed and power density are currently the goals pursued by high-speed train design.The pantograph system composed of the pantograph and the catenary is the only entrance for the train to obtain power.During the operation of the train,the pantograph strip and the contact wire are relatively sliding and electrically contacted to achieve current flow.When the train is running at high speed,due to the friction heat generated by the violent friction between the pantograph and the catenary,the Joule heat generated by the transmission of the traction current,the arc heat caused by the offline of the pantograph and the mechanical shock caused by the pantograph strip encountering hard spots,the pantograph strip is prone to abnormal wear and damage,which seriously affects the service life of the strip.As the demand for train running speed and traction power continues to increase,traditional pantograph-catenary system will face more severe challenges.In this paper,the domestic and foreign related researches on the electrical contact characteristics,temperature rise characteristics and friction and wear characteristics of pantograph-catenary system are described.A large number of existing studies have shown that the current-carrying temperature rise characteristics of pantograph strip are the key factors that determine their wear.In order to improve the heat dissipation,impact resistance and current stability of traditional pantograph,a new type of pantograph roller structure is proposed in this paper.Combined with friction and wear theory,electrical contact theory,and impulse theory,the temperature rise characteristics,impact resistance and dynamic flow characteristics of the pantograph roller are analyzed in depth.Based on the multi-physics coupling theory,a dynamic current collecting system simulation model is established for the traditional pantograph and the new pantograph.In order to verify the feasibility and accuracy of the model,an experimental test platform for the current-carrying temperature rise of the pantograph,including the traditional pantograph and the new rotatable pantograph,was built.Through experiments,the dynamic and static temperature rise characteristics and flow characteristics of the drum were proved,and the feasibility of the dynamic flow receiving system simulation model built was verified.Based on the pantograph-catenary dynamic current receiving system simulation model,the current-carrying temperature rise characteristics and temperature field distribution results of traditional and rolling bowheads under different pantograph-catenary relative running speeds are studied in depth.Compared with traditional strips,pantograph roller has extremely superior temperature rise characteristics and wear characteristics in the process of dynamic current-carrying friction,and with the increase of the relative speed of pantograph,the advantages of rotatable pantograph’s temperature rise performance continue to expand.A large number of experiments and simulations have been carried out for the traditional and new pantograph under different working conditions,verifying that the rotatable pantograph have good impact resistance,heat dissipation and wear resistance when the train is running at high speed.In order to further improve the mechanical and electrical performance of the pantograph-catenary system,and to explore the feasibility and comprehensive performance of the new pantograph roller flow receiving method,certain research ideas and reference significance are provided.