The fault location in the neutral un-effective grounding system has long been a hot issue. The universal distribution characteristics of the high-frequency transient component in the faulty phase current are firstly analyzed

based on which the main path of the high-frequency energy is defined and studied. Then

the valid high-frequency energy for each measuring point at head of feeder is extracted by means of wavelet transform

and the fault identification method based on the trajectory of faulty phase valid energy is finally put forward and assessed. Based on PSCAD/EMTDC platform

a real distribution network in Jiangxi Province is established

and the performance of proposed method under different fault conditions

fault resistances

neutral grounding modes and system parameters are verified.