计及高速铁路站内工况的车体过电压分布特性分析

Analysis on Railcar's Body Over-voltage Distributional Characteristics Considering Operating Conditions of High-speed Railway Station

针对动车组出站过程中出现的车体电势骤变及各节车体电势不均匀分布特性,本文以CRH2型动车组为研究对象,将动车组发车过程分为升弓、正常行驶和过牵引回流切断点绝缘节3种典型工况。首先分析动车组发车过程中车体过电压及不均匀分布特性的产生根源;其次,在ATP-EMTP平台上搭建车-网耦合等值电路暂态模型,考虑用电弧模型模拟动车组过侧线绝缘节时出现的接地电弧对车体的影响;然后,针对高速铁路站内3种典型工况下的车体过电压及分布特性进行仿真计算;最后,从接地优化角度探讨电缆屏蔽层接地布局,主回路接地方式及车体接地方式对站内各工况下列车车体电势分布特性的影响规律,提出相应的车体过电压防护方案。

Aiming at the sudden change and uneven distribution of the electric potential of railcar body when EMU （electric multiple unit） is leaving station, with CRH2 EMU as the research object, this paper divided the process of EMU＇s leaving station into three typical operating conditions： pantograph rising, normal drive and passing of insulated joints of traction return current cut-off points. Firstly, the origin of railcar body surge over- voltages and their uneven distributional characteristics when EMU leaves the station was analyzed. Subsequently, the railear-network coupling equivalent circuit transient model was built on the platform of ATP-EMTP, in which an arc model was built to simulate the effect of the grounding arc on the railcar body, caused by EMU that passes the insulated joints of the sidetrack. The railcar＇s surge over-voltages and their distributional charac- teristics considering each operating condition of high-speed railway station were analyzed by simulation calculation on this basis. At last, the effects of grounding points＂ layout of high-voltage cable shielding layer and earthing methods of the main loop and railcar on vehicle over-voltages＇ distributional characteristics considering each operating condition of EMU＇s leaving the station were analyzed. Based on above simulated calculation results, corresponding railcar＇s body over-voltage suppression measures were proposed.