Because of the complex control strategy and weak feed characteristics of soft normal open points (SNOP)

traditional fault location methods of distribution networks are no longer applicable to flexible distribution network (FDN). A method for fault location in FDN using waveform similarity of positive-sequence current component is proposed. Firstly

considering the typical control strategy of SNOP

the short-circuit fault characteristics of FDN are analyzed. Secondly

Tanimoto coefficients of positive sequence current component at different locations are calculated. By comparing the waveform similarity at different locations of positive sequence current component

a short circuit fault location criterion for FDN is constructed. The Teager energy operator (TEO) is used to accurately calibrate the fault time

and smart terminal units (STU) are used to transmit information. Finally

the proposed method is analyzed and verified through modeling and simulation. The results show that the proposed method can accurately locate the fault section

and has the ability to resist the influence factors such as fault location

fault type

transition resistance

sampling frequency and communication delay

which verifies the feasibility and effectiveness of the proposed method.