A Detection Method of Relative Capacitance Ratio

Abstract

The invention discloses a detection method of relative capacitance ratio. The present invention includes the following steps: step (1) coupling and reading the current value to ground at the end screen end of each capacitive high-voltage bushing, and selecting one of the points as the reference point C O , and the remaining points are taken as monitoring points C D ; Step (2) selects the ground current value at the same time, and calculates the relative capacitance ratio C OR ; Step (3) is based on the same principle of primary high voltage rate of change, according to the relative capacitance ratio C OR Changes in judging the stability of the relative capacitance; if the relative capacitance ratio C OR unchanged, it means that the relative capacitance stability of the bushing is good, indicating that the insulation state of the monitoring point is good; if the relative capacitance ratio C OR If it changes, its stability will obviously deteriorate, indicating that the insulation state of the bushing may deteriorate. The invention solves the problem that the insulation state of the medium cannot be judged by the capacitance change in the charging or on-line detection.

Description

technical field [0001] The invention belongs to the technical field of high-voltage detection, and in particular relates to a detection method of a relative capacitance ratio. Background technique [0002] The capacitive bushing is a high-voltage insulation detection carrier, and its capacitance change can reflect its insulation state to a certain extent. At present, capacitance value detection is one of the main methods to reflect the state of dielectric insulation. Its principle is to place the test object and the standard capacitor without dielectric loss under the same high-voltage waveform, and compare the relative capacitance between the two. [0003] In power failure detection, the detection of capacitance value is generally a routine detection item. However, in the live or online detection of the power grid, since the non-destructive standard capacitor cannot be connected, generally the capacitive current value to the ground can only be read by coupling at the groun...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a relative capacitance ratio detection method for the deficiencies of the prior art. This detection method solves the problem that the dielectric insulation state cannot be judged by the capacitance change in the charging or on-line detection.

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