Fault location of UHV DC transmission line based on variational mode decomposition and energy operator

Traveling wave fault location is widely used because it isn't affected by transition resistance and operation mode, but it is difficult to accurately and effectively detect the arrival time of fault traveling wave head in the early stage of fault occurrence. In view of this, a traveling wave head detection method based on the combination of variational mode decomposition and Teager energy operator is proposed. Firstly, the acquired fault traveling wave signal is decomposed into variational modes, and then the most sensitive IMF component is demodulated by Teager energy operator. The energy spectrum of the fault traveling wave signal is obtained. The first obvious mutation point in the energy spectrum is the arrival time of the first wave head of the fault traveling wave. The simulation results show that the location error of this method doesn't exceed ±0.2% of the actual fault distance, which proves the feasibility of the principle.