Detection and analysis device for direct-current magnetic biasing of power transformer and detection and analysis method thereof

Abstract

The invention discloses a detection and analysis device for direct-current magnetic biasing of a power transformer and a detection and analysis method thereof. The detection and analysis device is characterized in that a ground test point near a neutral point of a power transformer is connected to an input terminal of a voltage sensor (U) and the other end of the voltage sensor (U) is connected with a reference electrode; and the output terminal of the voltage sensor (U) is successively connected to a signal conditioner II (22), a data acquisition card II (24) and a server (31). The device iscapable of detecting the neutral point current of the power transformer and a polarization potential between a grounding grid ground potential of the power transformer and the reference electrode simultaneously, so that a relationship between the neutral point current of the power transformer and the polarization potential between the grounding grid ground potential of the power transformer and the reference electrode is obtained; and thus testing data are provided for the anti-direct-current-magnetic-biasing distribution design of the power transformer and the fault prevention. The influenceon the power transformer by the direct-current biasing phenomenon can be eliminated or reduced; and the safety and reliability of the power transformer operation are improved.

Description

technical field [0001] The invention relates to a detection and analysis device and a detection and analysis method for DC bias magnetism of a power transformer. Background technique [0002] The DC bias phenomenon exists in the power transformer in the power system. The reason is: the ground current of the HVDC power transmission system and the geomagnetic induction of the geomagnetic storm make the ground current exist in the earth, coupled with the existence of the earth resistivity, the ground current will cause the ground surface potential to be distorted within a certain range; The ground potentials of different power transformers are different, and then form a DC circulation circuit between different power transformers and the earth, resulting in the generation of DC magnetic flux in the core of the power transformer, resulting in a DC bias phenomenon. DC bias will cause increased noise and vibration of power transformers, and in severe cases, local overheating, loos...

AI Technical Summary

Problems solved by technology

This method is only for post-event investigation and maintenance after a fault occurs, and cannot realize the anti-DC bias layout design and fault prevention of power transformers, resulting in DC bias phenomena that are likely to affect power transformers, and the safety and reliability of power transformer operation remain to be seen. improve

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