| Static geometric parameters of the overhead contact system (OCS) ensure good dynamic properties of the pantograph-OCS systems, which is one of the dominant factors limiting the operating speed of trains. During construction, operation and maintenance, static geometric parameters are usually different from the original design, and the deviation can be referred as OCS static geometric parameter deviation. Influenced by natural and human factors, the deviation is inevitable. In order to ensure the safe operation of trains, it needs to fully understand the influence of OCS static geometric parameter deviation to the pantograph-OCS system.In the aim of optimizing the OCS static geometric parameters, the author introduced the concept of parameter deviation, took an OCS which is more widely used as the research object, explored the relationship between OCS static geometric parameters and dynamic properties of the pantograph-OCS system in order to find out the regularities of the influence, providing the theoretical support for the construction, operation and maintenance of the OCS.In the paper, firstly, the author discussed the causes of OCS static geometric parameter deviation, pointed out that the vast majority of OCS structure change can be reflected in position of the contact line, theoretically calculated the influence of the height of string and locating point and tension of the threads, quantitatively analyzed the impact of these factors on position of the contact line.Secondly, a finite element model of OCS-pantograph system was established. Based on the model, this paper mainly studied on the influence of OCS static geometric parameters to dynamic properties of the pantograph-OCS system, caused by heights of string and locating point and tension of the thread, and got a maximum range of the deviation that can ensure the good performance of the pantograph-OCS system and can be used to guide the design, construction and maintenance of the OCS.Finally, the author applied the theory into engineering practice, taking real data of WuHan-GuangZhou high-speed railway in calculation. Through the comparison between the condition with the generally existing OCS static geometric parameter deviation (maximum20mm on height of the conduct line with negative rag) and the no-deviation condition, the result stated the influence of OCS static geometric parameter deviation to dynamic properties of the pantograph-OCS system and verified the rationality of the maximum range of OCS static geometric parameter deviation. |
