Abstract: The traveling wave fault location of traditional double-circuit transmission lines are mainly studied

on the model with symmetric parameters. In order to solve the problem of traveling wave fault location of doublecircuit lines on the same tower with asymmetric parameters in engineering practice，a fault location method based on VMD-HT algorithm was proposed. Due to the coupling between lines and phases of the double-circuit transmission lines on the same tower，the six phases' currents were first decoupled to get six independent current mode components，and the characteristic mode components were obtained after comparative analysis. Then，the characteristic mode components were transformed by VMD-HT to extract the initial arrival time of the traveling wave head arriving at both ends of the lines，and the fault location was calculated according to the double-circuit lines location formula.Comparison and simulation of PSCAD and Matlab experiments show that the proposed algorithm has better accuracy of fault location than cubic B-spline wavelet packet transform and Hilbert Huang transform（HHT）algorithm. The model is extended from double-circuit transmission lines to four-circuit transmission lines，and the error is still within the allowable range，which verifies the correctness and universality of the proposed algorithm.

      Key words: traveling wave fault location；variational mode decomposition（VMD）；double-circuit transmission lines on the same tower；cubic B-spline wavelet packet transform；Hilbert Huang transform（HHT）