Partial discharge positioning device and method for ultra-long power distribution cable

Abstract

The invention relates to a partial discharge positioning device and method for an ultra-long power distribution cable. The device comprises a pulse signal generator, an oscillating wave voltage generator and a signal receiving device which are arranged at the head end of the cable, and a plurality of capacitive sensors arranged on spaced cable joints, wherein the capacitive sensor comprises a coupling unit, a signal acquisition module and a 4G module, the coupling unit is composed of a high-voltage coupling capacitor and an RLC coupling circuit, signals acquired by the signal acquisition module are transmitted to the signal receiving device through the 4G module, the high-voltage coupling capacitor is pre-buried between a cable joint grounding copper net and an outer semi-conductive layer,and an external wire is connected in series with the RLC coupling circuit. According to the device and the method, the defects that pulse echoes are difficult to detect and positioning is greatly influenced due to the fact that the length of the cable is too long and partial discharge signals are attenuated seriously are effectively overcome.

Description

technical field [0001] The invention relates to the technical field of state detection of distribution cables in power systems, in particular to a partial discharge positioning device and method for super-long distribution cables. Background technique [0002] Power cables are mostly laid underground, do not occupy surface resources, are not easily affected by severe weather such as strong winds, rainstorms, lightning, and snow, and are less likely to be mechanically damaged during operation. Therefore, they are increasingly replacing traditional cables. Overhead lines have become an important part of urban power transmission and distribution networks. However, various faults may still occur in the power cable during operation, and the main reasons for the occurrence include poor quality of the cable itself, damage during installation, and insulation degradation during long-term operation. Faults caused by insulation degradation are often holistic and global. The cable its...

AI Technical Summary

Problems solved by technology

However, in the actual operation process, due to the serious attenuation of the high-frequency partial discharge signal in the cable, it is often difficult to complete the transmission of two cable lengths for the long cable partial discharge pulse signal, and it is overwhelmed by noise

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