南方电网输电线路瞬时人工接地短路试验

摘要

Manual instantaneous grounding test of transmission lines is a key procedure in HVDC project commissioning. This paper describes the manual instantaneous grounding test method of transmission lines applied to multiple HVDC projects of CSG, and simu-lates the influence of grounding current and soil resistivity on regional step voltage using CDEGS software. Simulation results show that when the grounding current is 10 kA, the soil resistivity of the short circuit area is 1 500 Ω·m, and the grounding device of current divergence tower is typically radial, the maximum step voltage of the test field within 30 m horizontal distants away from the tower base will exceed the safe limit, then the safe distant should be improved to reduce the test risk.%输电线路瞬时人工接地短路试验是直流输电工程调试的关键试验步骤。介绍了在南方电网多个直流工程中开展的输电线路瞬时人工接地短路试验方法,并采用CDEGS软件仿真计算入地短路电流、短路点土壤电阻率等参数对短路点区域地表跨步电压的影响及分布。仿真结果显示：在入地短路电流为10 kA,短路点场区土壤电阻率为1500Ω·m,散流杆塔接地装置采用山区典型放射状结构时,距离杆塔底座水平距离30 m的试验区域跨步电压最大值超过安全限值,存在试验安全风险,需进一步提高并校核试验安全距离。