In novel power system

the stability and safety of 10 kV distribution lines are crucial. Single phase grounding fault is a common type of fault in such systems

and its location has always been a technical challenge due to the small short-circuit current and difficulty in direct measurement. Therefore

a method for locating small current multi-point polymorphic single phase grounding fault sections in 10 kV distribution lines is studied. Fault indicators are used to collect fault signals from 10 kV distribution lines

and denoising is performed on the fault signals using the wavelet thresholding method based on empirical mode decomposition (EMD). The sample entropy of each section of 10 kV distribution lines is extracted from the fault signals. The average sample entropy difference is calculated based on sample entropy. The average sample entropy difference of all sections is sorted from largest to smallest

with the section corresponding to the maximum value being the section with small current

multi-point

and polymorphic single-phase grounding faults. The experimental results demonstrate that the section positioning results obtained by the research method are consistent with the actual location of the fault point

which proves that the positioning method is accurate

the positioning accuracy is up to 97.1%

and the positioning accuracy is basically stable at each fault point

and the maximum is only 9.7 s.