The Study On Lightning Protection For OCS In Direct Feeding System With Negative Feeder

According to the nearly 20000 kilometres running condition of electrization railway running at present in our country, there are frequent stroke-incidence in parts of transmission lines (such as Beijing railway station, Guangshen railway company), Flashover disturbance caused by lightning is one of the importance factors. With the increasing of running kilometer in electrization railway and the fast development in our country, evaluating the lightning protection performance of catenary and reducing stroke-incidence in catenary are very important questions either in theory or in practice.Based on the lightning protection research of catenary at present, insulation and insulation coordination of traction power supply system are analyzed. This paper analyzes different lighting condition on catenary, put forward a calculation method about atmosphere overvoltage and calculate lighting current amplitude and its probability of catenary flashover in different condition. According to the principle of traveling wave, the catenary calculation model in simulation calculation in SuiYu railway catenary system is set up. In this module, lightning current values, tower resistance, tower model and arrester model are considered.The results shows that the lightning withstand level of catenary is not high when there are no arresters. Most lighting along the railway may cause insulator flashover in catenary. The lightning withstand level of catenary is higher when there are overhead line and some arresters. Grounding resistance of catenary pillar has the most important effect on lightning withstand level of catenary.