Non-contact method for acquiring transient voltage traveling wave signal

Abstract

The invention relates to the technical field of high voltage cable fault detection, and more particularly to a non-contact method for acquiring a transient voltage traveling wave signal. The method comprises: determining spatial electromagnetic signal distribution near a cable terminal according to the spatial electromagnetic distribution of the cable terminal and the high-frequency signal propagation characteristics; selecting a physical structure, electromagnetic parameters and installation position of an acquisition unit to install the acquisition unit; transmitting a fault signal collectedby the acquisition unit to a data processing unit through a signal cable; using the data processing unit to analyze and process electric quantity signals when collecting high voltage cable faults, obtaining the modulus maximum point by a wavelet algorithm to determine the fault start time. The non-contact method for acquiring the transient voltage traveling wave signal is based on the principle of space electromagnetic induction, can obtain the transient voltage traveling wave signal in the fault signal of the high-voltage cable fault and obtain accurate fault occurrence time without physicalcontact with the high-voltage cable, and meet high voltage cable fault online positioning requirements based on double-end traveling wave principle.

Description

technical field [0001] The invention relates to the technical field of high-voltage cable fault detection, and more specifically, to a method for non-contact acquisition of transient voltage traveling wave signals. Background technique [0002] After the power line fails, it is urgent to determine the location of the fault. Since the location of the fault can be calculated from the distance from the fault point to the measurement point, determining the location of the fault first requires obtaining relevant signals of the fault. Traditional overhead line fault signals are extracted from protective voltage and current transformers. Due to the limitations of protective voltage and current transformer structures, parameters and load characteristics, their transmission characteristics cannot meet the positioning accuracy requirements of high-voltage cable lines. Since faults are often accompanied by transient voltage traveling wave signals, transient voltage traveling wave sign...

AI Technical Summary

Problems solved by technology

Traditional overhead line fault signals are extracted from protective voltage and current transformers. Due to the limitations of protective voltage and current transformer structures, parameters and load characteristics, their transmission characteristics cannot meet the positioning accuracy requirements of high-voltage cable lines.

Since faults are often accompanied by the occurrence of transient voltage traveling wave signals, transient voltage traveling wave signals can be used as the basis for online fault location. However, there is no effective, accurate and safe method for extracting transient traveling wave signals generated by faults.

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