大型接地网多维度评价及指标校核

Multi-aspect Assessment and Parameter Calculation Method of Large Grounding Grid

针对目前越来越受关注的大型接地网科学评价问题,以大型接地网安全性为中心,提出涵盖接地网电位时空分布特性、散流性能、均压性能和健康性多个要素的多维度评价理念,给出地电位升和网内电位差控制值,以及接地阻抗取值的校核原则和方法,提出以10k V及以下金属氧化物避雷器和电力电缆护层保护器在接地故障期间的能量吸收来校核地电位升控制值和接地阻抗取值,给出以二次设备耐受为校核原则的网内电位差的推荐控制值(1000V)。此外,还提出地网电气和土壤理化特性诊断相结合的导体腐蚀性诊断解决方案。所得的结论对大型接地网设计和运行维护具有重要的指导价值。

Based on the safety evaluation, the multi-aspect assessment concept of large grounding grid was presented,which covered ground potential time-space distribution characteristics, current disperse characteristics, potential equalizing performance and health condition. The checking principles and methods of ground potential rise based on the energy absorb of 10 k V arrester and cable sheath protector during fault, ground potential difference(1000 V), ground impedance and corrosion diagnosis based on both electrical and soil physicochemical properties were recommended, together with the corresponding solution, which were of great reference value for both design and safety evaluation of large grounding grid.