摘要

To solve the problems of short effective time span, dead zone existence, and being highly restricted by the practical current transformers (CTs) configuration, a novel fault line selection method based on the construction of directional traveling wave is proposed, which adopts transient signals of single phase current and bus phase voltages. By using the linear combination of single phase current and bus phase voltages, characteristic directional traveling wave (CDTW) in mode domain is established. Dyadic wavelet transform is applied to calculate the decomposition coefficient of CDTW in certain frequency span. The integral relationship between forward and backward directional traveling wave is obtained and the fault line selection is accomplished. Mathematical deduction and simulation results prove that the proposed method has high accuracy and long effective time span. The definition of characteristic directional traveling wave is reasonable. The performance of the proposed method is not affected by the neutral point grounding type.

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