The soil environment in Ningxia is complex

characterized by the coexistence of Yellow River irrigation areas

arid zones

and semi-humid zones

with a significant salinization gradient. Substation grounding grids in this region are subject to long-term soil corrosion. However

a quantitative ranking of soil factors affecting grounding grid corrosion in this area has been lacking

resulting in an absence of localized basis for corrosion prevention design and maintenance. To address this issue

soil samples and buried grounding plates were collected from more than forty sites across Ningxia for testing. Based on a combined analysis using entropy weight method (EWM) and random forest (RF) algorithm

the key parameters of soil corrosion affecting substation grounding grids in Ningxia were investigated. First

the actual corrosion rate of grounding grid conductors was obtained by processing grounding plates using the weight loss method. Then

the entropy weight factors and overall influence degrees of soil physicochemical factors were calculated using the EWM and RF algorithms. Finally

the contribution weights of soil parameters to the corrosion rate of grounding grid conductors were determined and visually ranked. The results reveal that sulfate ion concentration has the greatest contribution to grounding grid corrosion in Ningxia

followed by chloride ion concentration

moisture content

resistivity

and porosity. Sulfate ions and chloride ions should be regarded as primary control targets for corrosion prevention design

material selection

and cathodic protection.