Grounding grids corrosion diagnosis and information digging of uncertain branches

A set of uncertain branches related with each other is defined as an uncertain branch group for grounding grid corrosion diagnosis. The methodology to determine uncertain branch groups is described. It is pointed out that evaluation of uncertain branches can be carried out in uncertain branch groups, respectively. A novel method based on dichotomy to calculate the maximum and minimum resistances of uncertain branches is presented. An approach to evaluate the probability distribution of the resistances of uncertain branches is proposed. The entropy of the resistance of an uncertain branch is described. An experimental grounding grid with sixty branches is used as an example showing that the proposed methods are feasible and obtain more diagnosis information, it is helpful to evaluate the diagnosis results of grounding grids.