The invention relates to the technical field of power maintenance, and discloses a
signal injection parameter determination method for a 10kV distribution line grounding fault. The method comprises the following steps: injecting a
broadband sweep frequency pulse into a line, adaptively setting a sweep frequency step according to the length of the line, and obtaining no-
load spectrum characteristic data; calculating correlation among the candidate frequency points in the available
frequency band, and selecting a plurality of characteristic frequency points of which the correlation is lower than a threshold value; injecting energy according to the
frequency band where each characteristic frequency point is located, so that the energy is inversely proportional to the
attenuation coefficient; collecting a feedback
signal and extracting a plurality of response features to form fault
feature data; performing similarity comparison on the fault
feature data and a standard fault feature
library to obtain a fault type and a matching degree; if the matching degree is lower than a threshold value,
encryption sampling is performed in the sensitive
frequency band, and extraction and matching are repeated after energy is increased; and calculating the fault distance by using the
phase deviation difference of the at least two characteristic frequency points. The self-adaptive determination of the injection parameter is realized, and the detection success rate and the positioning precision of the hidden fault are improved.