Distribution network fault section positioning method based on primary and secondary fusion switch and traveling wave device

The invention discloses a distribution network fault section positioning method based on a primary and secondary fusion switch and a traveling wave device, and the method comprises the steps: installing the primary and secondary fusion switch and a traveling wave collection device in a distribution network trunk line, carrying out the partitioning according to the midpoint of the distribution network trunk line, obtaining a partition 1 and a partition 2, and numbering the branch points in each partition; calculating a reference time difference between the partition 1 and the partition 2 according to the line parameters; when a distribution network trunk line breaks down, the three-phase voltage of the partition 1 and the three-phase current of the partition 2 are collected respectively, and Karrenbel transformation is carried out to obtain a voltage traveling wave 1-mode component and a current traveling wave 1-mode component; the partition where the fault is located is judged through an MVMD-Teager energy op