Power transformer winding deformation detection method based on vibration analysis

Abstract

The invention discloses a power transformer winding deformation detection method based on vibration analysis. The method comprises the following steps of: (1) arranging vibration detection points, and monitoring load current and a vibration signal of each detection point in real time; (2) acquiring an impact hopping vibration signal, and judging a tripping form of a power transformer; (3) performing winding deformation diagnosis on a first power transformer according to an extracted fixed frequency; and (4) performing winding deformation diagnosis on a second power transformer according to change of a nonlinear degree. By the detection method, the vibration signals are processed and judged, so that electric connection with the power transformer is not needed, and influence on the running of the whole power system is avoided; due to the method, real-time and on-line detection is realized, and detection can be performed without stopping the power transformer, so that the influence on the running of the whole power system is avoided; small and intermediate deformation of a winding of the power transformation can be detected; and moreover, the method is easily integrated into a transformer fault diagnosis instrument and is easy to operate and favorable for popularization.

Description

technical field [0001] The invention belongs to the technical field of power transformer safety fault detection, and in particular relates to a vibration analysis-based detection method for power transformer winding deformation. Background technique [0002] Large power transformers are the key equipment in the power grid system. The failure of power transformers can interrupt the transmission network and cause serious economic losses and social impacts. Therefore, it is very necessary to accurately monitor whether large-scale power transformers fail and ensure the normal operation of the transformers. [0003] Transformer faults are divided into winding faults and core faults, and winding faults occur more frequently. The manifestations of winding faults are generally radial deformation and axial tilt (collectively referred to as deformation). In more serious cases, serious situations such as inter-turn short circuit may occur in the winding. The main cause of winding def...

AI Technical Summary

Problems solved by technology

This method is simple and easy to implement, and has been widely used; however, it is not sensitive to certain deformations and mild to moderate deformations, which may easily lead to misjudgment

[0006] The short-circuit impedance method is to detect whether the winding is deformed by measuring the change of the short-circuit impedance of the winding before and after the impact of the winding. It is more sensitive to some types of deformation than the frequency response method. However, due to the use of a single power frequency, the sensitive range is limited and susceptible to interference

[0007] Therefore, the above two methods have low diagnostic accuracy for mild to moderate deformation of the winding, and cannot perform online detection.

Therefore, it is very important to detect whether the transformer winding is deformed online as early as possible for the stable operation of the transformer and to take corresponding measures. At present, there is no effective solution for detecting mild and moderate winding deformation, and there is no online detection scheme for winding deformation.

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