In practical engineering

issues such as misinformation

missed reports from the feeder terminal unit (FTU)

as well as malfunctions or false operations of protection devices

can complicate the fault localization and isolation process in distribution networks.This paper uses a multi-layer model to introduce a fault section localization method for active distribution networks.Using multi-source information for fault section localization reduces the probability of localization failure caused by the distortion of single fault information.Firstly

the protection action information collected by the information protection system is used to determine the fault area.Then

an improved immune algorithm is deployed to process the FTU telemetry information within the fault region

thereby facilitating fault localization and obtaining the final result.The simulation tests conducted on an IEEE 33-node distribution network with distributed generation (DG) demonstrate the efficacy of the proposed method in effectively improving the speed and accuracy of fault section localization.