Hybrid multi-terminal DC power transmission line fault positioning method considering power transmission line structure

The invention discloses a hybrid multi-terminal DC power transmission line fault positioning method considering a power transmission line structure. The method comprises the following steps: determining an estimated fault interval section; determining an estimated fault position according to the estimated fault section; based on the estimated fault position, correcting an original current frequency spectrum of a fault traveling wave head at each end of the line to obtain a corrected frequency spectrum in which power transmission line structure frequency spectrum change and line terminal station frequency spectrum change are corrected; determining a fault traveling wave head frequency according to the correction frequency spectrum; determining the actual traveling wave velocity of each end of the line according to the frequency dependent characteristic of each line interval section and the fault traveling wave head frequency; and determining an actual fault position according to the actual traveling wave veloc