客运专线接触网保护线兼作避雷线的防雷效果评估

Evaluation on the Lightning Protection Effect of Protective Wire of Catenary System for Passenger Dedicated Line Served as Lightning Conductor

接触网无备用且工作环境恶劣,极易遭受雷击而影响铁路运输安全。本文采用雷电直击承力索、正馈(AF)线和保护(PW)线时接触网的耐雷水平及雷击跳闸率以及感应雷作用下的雷击跳闸率等指标,研究PW线兼作避雷线的防雷效果。结果表明:对于采用AT供电方式的客运专线高架区段,直击雷是引起接触网雷击跳闸的主要原因,约占其合计雷击跳闸率的90%;由于AF线的雷电屏蔽范围大,耐雷水平低,因此防止雷电直击AF线是降低客运专线雷击跳闸率的关键;通过升高PW线使其兼作避雷线,虽然由感应雷引起的接触网雷击跳闸率有所增加,但可有效地防止雷电直击AF线,合计雷击跳闸率降低约69%。

There is no backup for catenary system and its working conditions are rather poor. It can be easily damaged by lightning strikes and the safety of railway transportation will be affected. Such indexes as the lightning withstand levels and the lightning outage rate of catenary system when using messenger wire against direct lightning strikes, positive feeder （AF） and Protective Wire （PW） as well as the lightning outage rate under induction lightning are adopted to study the lightning protection effect of PW served as lightning conductor. The results indicate as follows that, for the elevated section of passenger dedicated line with AT power supply mode, direct lightning strike is the main reason for the lightning outage of catenary system, it accounts for approximately 90% of the total. Since the lightning shielding range of AF is large and the lightning withstand level is low, preventing AF from direct lightning strike is the key to reduce the lightning outage rate of passenger dedicated line. By raising PW to make it serve as lightning conductor, although the lightning outage rate of eatenary system caused by lightning induction is slightly increased, it can effectively prevent AF from direct lightning strike, the total lightning outage rate is reduced about 69%.