500kV温南变电所接地网安全性问题的探讨

Discussion on Safety Problem of Grounding Mesh in 500 kV Wennan Substation

文章从接地阻抗、地电位升、接触电压和跨步电压的角度综合分析探讨了地处高土壤电阻率地区的500kV温南变电所接地网安全性问题,并提出了相应的安全防范措施,如通往变电所外的金属管加绝缘段隔离、通信电缆全部采用光缆、验算接触电压和跨步电压、降低电缆的感应电压以及避雷针采用集中接地等,最终使地网接地阻抗可放宽到0·5Ω仍能确保变电所安全运行和人身安全。

From the point of view of grounding impedance, grounding potential, contact voltage and step voyage, the safety problems of grounding mesh in 500 kV Wennan Substation were discussed and analyzed, which located at high soil resistivity area. The corresponding measures for safety were put forward, such as adding insulation section on metal water pipe for outgoing of outside substation, adopting optical cable for telecommunication cables, checking and calculating the contact voltage and step voltage, reducing the induction voltage of cable, as well as adopting concentrated grounding installation for lightning rod. The grounding resistance of grounding mesh can be up to 0.5 Ω, which can still ensure operation and personal safety in substation.