Research purposes: The earthing design idea is discussed in this paper for a newly - built traction substation on Xiamen - Shenzhen Railway with complex topographic and geologic conditions and high soil resistivity based on meeting the contact potential and step potential conditions in combination with requirements of current railway codes and IEEE standards concerned. At the same time,an optimal scheme is selected by comparison of economic benefits, providing a reference for the earthing design with similar soil resistivity condition.
Research conclusions:A proper earthing scheme should be adopted for the traction substation in consideration of local conditions. The earthing resistance of the substation may be increased to some extent upon verifying the contact potential and step potential. On the basis of this,different resistance reducing measures can be adopted for saving investment of the project under the premise of ensuring equipment and personnel safety.