Direct current cable defect detection method and device based on frequency band selection and medium

Abstract

The embodiment of the invention discloses a direct-current cable defect detection method and device based on frequency band selection and a medium, belongs to the technical field of cable defect detection, and solves the problem that in a direct-current cable test, an attenuated detection signal may be submerged by a noise signal under high frequency, and consequently a defect detection result is seriously interfered. Comprising the following steps: determining a detection frequency upper limit through a minimum signal amplitude and an output signal amplitude obtained by an impedance analyzer arranged on a direct current cable to be detected; constructing a fitness function based on the corresponding attenuated amplitude of the detection signal at the candidate frequency point and the frequency domain amplitude spectrum of the background noise in the current cable detection environment; based on the detection frequency upper limit and the fitness function, searching an optimal test frequency band upper limit frequency through an optimization algorithm; and determining a sweep frequency range based on the upper limit frequency of the optimal test frequency band, injecting a sweep frequency excitation signal into the head end of the direct current cable to be tested in the sweep frequency range, and performing cable defect positioning based on a received reflection signal.

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