Fault travelling wave ranging method based on GST-TT transform

Aiming at the problem of insufficient accuracy of wave head time calibration, a fault traveling wave ranging method based on GST-TT transform is proposed. Firstly, the sampled voltage traveling wave signal is decoupled to extract the line mode voltage signal; Secondly, the line mode voltage signal is generalized S-transformed; Thirdly, the appropriate high-frequency band is extracted as the fault characteristic band; Fourthly, using high-frequency aggregation and low-frequency suppression characteristics of TT transform's diagonal position elements, the arrival time of the wave head at the measuring end is accurately calibrated in the fault characteristic band; Lastly, the fault distance is obtained based on the fault ranging calculation method. The method can improve the calibration accuracy of the wave head time. The PSCAD simulation proves that the method has high accuracy, strong tolerance to transition resistance and anti-noise ability.This work is supported by National Natural Science Foundation of China (No. 51974151) and Liaoning Provincial Department of Education Key Laboratory Project (No. LJZS003).