Due to the increase of cable lines in small-current grounding distribution systems currently

traditional neutral point grounding modes and manual pulling method now is difficult to meet the security requirements of modern urban power grid. The action logic

main advantages and disadvantages of five kinds of grounding line selection tripping schemes are sorted ou

that is

parallel small resistance line selection

parallel medium resistance line selection

active intervention of arc extinction

distributed line selection and centralized line selection. Through the actual data and operation experiences of a electric power company

the centralized single-phase grounding line selection tripping scheme is recommended if the electrical equipment is already in operation

and the distributed single-phase grounding line selection tripping scheme can be selected if the equipment has not been put into operation.