Online monitoring method and device for converter transformer grid side bushing

Abstract

The embodiment of the invention provides an on-line monitoring method and device for a converter transformer grid side bushing. The method specifically comprises the following steps: synchronously collecting leakage current of a plurality of bushings under the same reference voltage; determining a relative dielectric loss value and a relative capacitance of each bushing relative to other bushings based on the leakage current; and determining the insulation state of the corresponding bushing according to the relative dielectric loss value and the relative capacitance. In other words, the insulation state of the bushing is monitored in an indirect mode. Compared with the prior art, the leakage current of a plurality of bushings running in the same phase is measured, the relative dielectric loss value and the relative capacitance change rate between devices are measured by mutual reference signals of the leakage current of a plurality of bushings, and the insulation state of the bushings is judged according to the relative dielectric loss value and the relative capacitance change rate. According to the scheme, factors influencing the measurement accuracy can be removed in the process of calculating the relative quantity, so that the reliability is very high, and the problem that the reliability is relatively poor when the insulation state of the sleeve is monitored in an existing scheme is solved.

Description

technical field [0001] The invention relates to the technical field of electric power equipment, in particular to an on-line monitoring method and device for bushings on the transformer grid side. Background technique [0002] The converter transformer plays an important role in the transmission power and electrical isolation of the AC-DC system. It is one of the core equipment of the DC converter station, and its safe and stable operation affects the safe and stable operation of the converter station. As the ground insulation and support of the high-voltage lead wire, the bushing on the side of the converter transformer plays a vital role in the reliable and stable operation of the converter transformer. [0003] The damage of the bushing is mainly manifested in the partial breakdown of the capacitive shielding layer caused by overvoltage or partial insulation creepage, and it is also manifested in the damp or insulation deterioration of the bushing. The capacitance and di...

AI Technical Summary

Problems solved by technology

[0005] In view of this, the present invention provides an on-line monitoring method and device for the bushing on the side of the converter transformer, so as to solve the problem of poor reliability of the current on-line monitoring scheme when monitoring the insulation state of the bushing

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