On-line fault diagnosis device and method for capacitive current transformer

Abstract

The invention discloses an on-line fault diagnosis device and method for a capacitive current transformer. The on-line fault diagnosis device comprises a Rogowski coil, a leakage current signal pre-stage processing module, a data acquisition module, a denoising processing module, a leakage current characteristic extraction module and a fault diagnosis module. The on-line fault diagnosis device and method can diagnose damp inside of a main insulator, partial discharge, breakdown of a capacitive screen, unstable earthing of an end shield and breaking of an internal zero screen lead and a zero screen of the capacitive current transformer on line and distinguish faults of the main insulator and faults of a secondary coil, further expansion and development of the faults of the capacitive current transformer are prevented and reduced, and the maintenance work guided correctly.

Description

technical field [0001] The invention relates to the field of on-line monitoring of power equipment, in particular to an on-line fault diagnosis device for a capacitive current transformer. Background technique [0002] The capacitive current transformer is one of the important equipment in the power system, and its normality directly affects the safe operation of the power system. In recent years, the faults of capacitive current transformers have shown an upward trend, which increases the probability of equipment damage and seriously threatens the normal operation of current transformers. Currently, routine routine tests (such as insulation resistance, dielectric loss measurements) are sensitive to penetrating flaws, but not sensitive enough to local flaws. Infrared temperature measurement technology can only be detected when the fault develops to a certain extent and heating occurs, so it is difficult to diagnose the initial fault. The oil chromatography detection techno...

AI Technical Summary

Problems solved by technology

In recent years, the faults of capacitive current transformers have shown an upward trend, which increases the probability of equipment damage and seriously threatens the normal operation of current transformers.

Currently, routine routine tests (e.g. insulation resistance, dielectric loss measurements) are sensitive to penetrating flaws but not sensitive enough to local flaws

Infrared temperature measurement technology can only be detected when the fault develops to a certain extent and heating occurs, and it is difficult to diagnose the initial fault

The oil chromatography detection technology can detect the initial failure of the capacitive current transformer, but the technology has the following two shortcomings for the transformer: (1) Off-line oil chromatography detection needs to take oil samples frequently, and there is not much insulating oil in the transformer body , taking oil samples frequently will lead to lack of oil in the transformer and affect its safe operation; (2) The online oil chromatography detection equipment is expensive and not suitable for a single transformer

High-frequency partial discharge and ultrasonic partial discharge detection technology can detect the internal discharge fault of the transformer, but only when the internal discharge of the transformer can detect the fault, it is difficult to achieve online continuous detection, and this method cannot detect the damp of the capacitive screen inside the transformer Waiting for failure

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