研究目的: 牵引变电所的接地网是保证电气化铁路安全运行,电气设备正常工作和工作人员人身安全的重要设施,研究牵引变电所的接地技术具有重要意义。本文从设计人员的角度对我国牵引变电所工程接地方案中经常碰到的几个问题进行分析和探讨,并提出相关的建议。
研究结论: ( 1) 在某些条件特殊或非常重要的牵引变电所接地网设计中,有必要提升设计手段,引入接地辅助设计软件,确保接地网的安全。( 2) 不应将最大接地短路电流看作入地短路电流,应考虑与接地网连接的架空避雷线的作用,计算工频分流系数。( 3) 在进行接地网优化设计时,应适当采用不等间距布置方式。( 4) 接地网材料不应盲目认为铜材一定抗腐蚀能力强,应考虑腐蚀原电池效应和土壤环境因素的影响。
Research purposes: The grounding grid of the traction substation is the key installation to ensure security of service of the electrified railway,normal operation of electric equipments and safety of the staff. It is meaningful to research technology of grounding grid of the traction substation. This paper analyses and discusses several common problems on grounding plan in substation projects while stating the designer’s side,and offers some related suggestions.
Research conclusions: ( 1) It’s necessary to upgrade design method to ensure safety of the grounding grids of special or very important traction substations by using computer - aided design software. ( 2) The maximum short - circuit current should not be taken as the grounding current,the effect of overhead ground wire connected with the grid should be considered,and the current divider coefficient should be calculated. ( 3) The designers should adopt unequally spaced arrangement in optimizing grounding grid when necessary. ( 4) The designers should not hold the opinion that copper must be resistant to corrosion,they also should take the effect of galvanic corrosion and environmental factor of the soil into consideration.