通信铁塔往往距离机械室较近,当其遭受雷击时会引起机械室地网的电位升高,该暂态电位升可能导致机械室内弱电设备的损坏.本文以该问题为切入点,依据宝兰客专某通信铁塔地网与机械室地网施工图,建立雷电暂态条件下的响应计算模型.以该模型为基础计算分析了当通信铁塔地网有雷电流注入时机械室地网在不同因素影响下的电位变化情况,包括两地网有无等电位连接、两地网距离和土壤电阻率等.计算分析数据表明:两地网间距从5 m增加至20 m时,机械室地网暂态电位可降低70％;若有等电位连接时机械室地网暂态电位会高10倍,并据此给出相关工程建议.%When the communication tower,which is always close to the mechanical equipment room,is struck by lightning,the potential of the grounding grid of the mechanical equipment room will be increased,in which the electronic equipment may be damaged.In this paper,firstly,the corresponding lightening transient calculation model was established,based on the construction drawings of the grounding grid of the communication towers and mechanical equipment room in the Baoji-Lanzhou high-speed railway system.On the basis of the model,an analysis was made on the changes of the potential of the grounding grid of the mechanical equipment room under the influence of different factors including the equal potential connection between two grounding grids,the distance between two grounding grids and the earth resistivity,when the communication tower was struck by lightening.The results showed that the transient potential of the grounding grid of the mechanical equipment room can be reduced by 70％ when the distance between the two grounding grids increased from 5 m to 20 m.The existence of the equal potential connection would make the transient potential of the grounding grid of the mechanical equipment room increase 10 times.At last,some suggestions were proposed based on the research results.
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