接触网断线落在碳纤维车体的过电压仿真分析

Simulation analysis of over-voltage of broken contact line falling on CFRP body of driver’s cab

电气化铁路运行环境的复杂性使接触网存在断线的可能,断开的接触网导线落在动车表面容易形成车体过电压。为了评估碳纤维动车车体由于导电性劣于传统铝合金车体而引起的过电压危害,基于某公司设计的半碳纤维半铝合金司机室车体结构,建立了动车组浪涌过电压电路模型。通过仿真求解接触网断线落在动车司机室车顶时司机室不同位置浪涌过电压的传输特性,得到车体过电压最大幅值26 kV,在60μs内快速衰减,对车载电子设备造成安全隐患,并提出将车载设备的接地线缆直接连接在车厢的接地碳刷附近,为司机室车体的过电压防护设计提供理论依据。

Complexity of the railway operation environment makes it possible to break the contact line,and the broken contact wire falling on the surface of the motor train unit will lead to the overvoltage of the cab body.In order to evaluate the over-voltage damage of Carbon Fiber Reinforced Polymer/Plastic(CFRP)cab body due to its poorer conductivity than that of traditional aluminum alloy cab body,the circuit model of CFRP train body is established based on the semi-CFRP semi-aluminum alloy structure design.The transmission characteristics of surge overvoltage in different positions of the cab body are solved by simulation.The maximum voltage reaches 26 kV,and attenuates rapidly in 60μs,which is a potential safety hazard for on-board equipment.It is proposed that the grounding wires of on-board equipment should be connected directly near the grounding brush of cab body,which provides a theoretical basis for the design of overvoltage protection of CFRP cab body.