海南省变电站接地网土壤腐蚀情况调研与分析

Survey on Soil Corrosion of Grounding Grid of Power Substations in Hainan Island

针对海南省内变电站接地网土壤腐蚀问题,对海南境内17个地区,共计33所变电站(11座35 k V变电站,17座110 k V变电站和5座220 k V变电站)进行调研,对变电站接地网实际腐蚀程度进行了分类。同时对海南省各变电站接地网所处土壤环境的腐蚀等级进行评价,结果显示,33所变电站内土壤腐蚀等级为C2~C5级,其中处于C2级的仅8个,占24.2%,属轻度腐蚀;处于C3级的15个,占全部的45.5%,属中等腐蚀;处于C4、C5级的10个,占全部的30.3%,为严重腐蚀、重度腐蚀;对海南省各变电站内直流杂散电流强弱程度进行测量,均处于中、高级。分析了接地网土壤腐蚀的原因。

A survey on soil corrosion of grounding grid for power substations in Hainan Island was performed, by which 33 substations, i.e. 11 substations of 35 k V, 17 substations of 110 k V and 5 substations of 220 k V located at 17 regions of the Island were involved. Then the corrosion degree of grounding grids at the power substations was also classified. At the same time, the corrosivity of the soil in Hainan province was evaluated. Results showed that the soil corrosivity for all the 33 substations could be ranked from grade C2 to C5. Among the 33 substations, the soil corrosivity of 8 substations was ranked as C2 i.e. slight grade; that of 15 was ranked as C3 i.e. moderate grade; and that of the rest 10 was ranked as C4 or C5 i.e. heavy or severe grade. Accordingly, the intensities of DC stray current for all the sites of substations were measured; they could be ranked in the range form middle to high level. Finally,the corrosion causes of grounding grid were analyzed.