Distribution network fault positioning method and system

Abstract

The invention discloses a distribution network fault positioning method. The method comprises the following steps: acquiring a traveling wave signal of a fault current; carrying out Karenbauer phase-mode transformation processing on the traveling wave signal to generate a traveling wave component; carrying out variational mode decomposition processing on the traveling wave component to generate anIMF component; obtaining a high-frequency modal component in the IMF component; calculating a Teager energy operator according to the high-frequency modal component; detecting arrival time of a faulttraveling wave according to the Teager energy operator; and calculating a fault position according to the arrival time. The invention also discloses a distribution network fault positioning method and system. Variational mode decomposition and the Teager energy operator are combined to form a single-ended traveling wave distance measurement method, which can be complementary with a double-ended distance measurement method; and meanwhile, refraction and reflection waves can be accurately distinguished, and the positioning precision is improved.

Description

technical field [0001] The invention relates to the field of electric power technology, in particular to a distribution network fault location method and a distribution network fault location system. Background technique [0002] The research and application of precise location of single-phase ground fault in distribution network has been unsatisfactory due to the influence of neutral point grounding mode. In addition to weak fault features, some common methods of extracting fault signals also have their inherent defects, specifically: [0003] The traveling wave detection method of wavelet transform has a great advantage in detecting the moment when the traveling wave arrives at the measurement point, but it has high requirements for the selection of wavelet basis functions and decomposition scales, and the selection of appropriate wavelet basis functions and decomposition scales must Analyze according to the specific signal, otherwise, the effect of traveling wave head de...

AI Technical Summary

Problems solved by technology

[0003] The traveling wave detection method of wavelet transform has a great advantage in detecting the moment when the traveling wave arrives at the measurement point, but it has high requirements for the selection of wavelet basis functions and decomposition scales, and the selection of appropriate wavelet basis functions and decomposition scales must Analyze according to the specific signal, otherwise, the effect of traveling wave head detection is not ideal

[0004] The Hilbert-Huang transform traveling wave detection method has certain advantages in practical applications, but its method has certain defects in theory, such as modal aliasing, over-envelope and under-envelope, etc. It will affect the accuracy of distance measurement and positioning to a certain extent.

Images