On-line detection method for transformer winding short-circuit fault based on spatial three-dimensional curve analysis

Abstract

An online detection method for transformer winding short-circuit faults based on spatial three-dimensional curve analysis. The △V‑I is constructed by the sinusoidal quantity represented by the primary-side and secondary-side voltage difference primary-side current and the primary-side and secondary-side current difference. 1 ‑△I space three-dimensional curve trajectory to realize online detection and location of transformer winding turn-to-turn short-circuit fault; by comparing and analyzing the difference of elliptical trajectory of three-dimensional space curve on different projection planes, online detection and fault location judgment of winding short-circuit fault can be realized. The method proposed by the present invention contains more fault characteristic information, and can detect whether a short-circuit fault occurs in the transformer winding and the severity of the fault under the state that the transformer does not stop, and can also realize the position discrimination of the winding short-circuit fault. Provide a reference for the staff to find and eliminate hidden troubles in time.

Description

technical field [0001] The invention relates to the field of on-line detection of short-circuit faults of power transformer windings, in particular to an online detection method of short-circuit faults of transformer windings based on spatial three-dimensional curve analysis. Background technique [0002] As the core equipment of the power system, the transformer's efficient, reliable and trouble-free operation is an important prerequisite for reliable power supply. However, power transformers have various failure factors in the complex field operation environment, and winding deformation failure is one of the important reasons that may lead to transformer damage. Winding deformation faults have a cumulative effect. With the continuous development of fault severity, sudden catastrophic accidents or equipment outages may occur in transformers, which will cause huge losses to the national economy and bring inconvenience to people's production and life. . For this reason, sch...

AI Technical Summary

Problems solved by technology

Although the △V-△I two-dimensional curve analysis can carry out online detection and identification of the severity of the winding short-circuit fault, it is difficult to effectively evaluate the location of the winding fault, which is obviously not conducive to the staff to find and eliminate hidden faults in time

[0004] For a single-phase transformer, there are four quantities that can be measured by existing measuring equipment, namely Based on △V-I 1 The online detection method of transformer internal fault based on curve trajectory analysis only uses three quantities, namely and and Although the difference in value and phase is very small, due to the existence of the excitation branch, the two will not be completely equal

neglect It may cause the loss of some important fault characteristic information, which may have an adverse effect on accurately judging the type and location of the fault

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