Power distribution network fault positioning method based on voltage amplitude difference

The invention relates to a power distribution network fault positioning method based on voltage amplitude difference. The method comprises the steps of collecting a line head end voltage amplitude; calculating an actual fault voltage amplitude difference; maintaining the same fault type and fault resistance to simulate the actual faults of all branches, calculating the simulated fault voltage amplitude difference of each branch, calculating the index of each branch, and determining the branch corresponding to the minimum index as the fault branch; starting from a fault branch, performing fault simulation at a fixed positioning step length, calculating and storing voltage amplitude differences simulated under various fault distances, and finally generating an online database; generating a polynomial according to the data characteristics of the database; and performing waveform fitting and solving, then taking a root which is a positive real number and is smaller than the branch length as a final solution, and