To reduce the frequent occurrence of misdiagnosis and missed diagnosis in the fault diagnosis of substation grounding networks

a bidirectional fault diagnosis method based on target branch dimension reduction for grounding networks is proposed. First

a model of grounding network based on electrical network theory is established. Next

fault branch detection direction and healthy branch reduction direction are set. The fault branch detection direction transforms the fuzzy fault branches into clear fault branches

while the healthy branch reduction direction defines the fault influence coefficient based on the evaluation function. The branch with the highest influence coefficient is selected as the target dimension reduction object each time

achieving the reduction of fuzzy health branch topology structure. Finally

the improved firefly algorithm (IFA) with Logistic mapping and adaptive weight optimization is used to solve the objective function. Through simulation experiments on specific cases

the proposed method is verified to ensure diagnosis accuracy

while minimizing misdiagnosis and missed diagnosis.