Methodology to locate and quantify radial winding deformation in power transformers

Abstract

Frequency response analysis (FRA) is a tool that can be used to detect changes within the structural geometry of a transformer. One application of FRA is to detect winding displacement after the transformer experiences an overcurrent event. This paper proposes a methodology which will facilitate both locating and quantifying winding deformation. The procedure is based on the fitting of a Gray Box transformer model to FRA measurements which were recorded both before and after the fault. Subtle variation in key parameters of the model can then be used to quantify winding deformation severity. The research will demonstrate the applicability of this approach to a wide range of transformer applications by using FRA from a modified 1.3 MVA distribution transformer, and assessing the change in key parameters relative to the emulated buckling introduced to the windings. The authors propose that this approach is ideally suited for use within an automated diagnostic system which will locate, diagnose and quantify winding deformation within power transformers. High Voltage

Elegant procedure to estimate series capacitance of a uniform transformer winding from its measured FRA: implementable on existing FRA instruments

“…3. In the past decade or so, FRA has become a de facto monitoring tool of the power utilities to assess the mechanical integrity of the winding [13][14][15][16]. Keeping this in mind, the authors' research group successfully demonstrated the possibility of indirectly estimating C s from measured FRA data, for both single and three-phase transformers [17,18].…”

“…However, these can be computed and stored for any desirable higher value of N if required. Once the numerical value of Π scnf /Π ocnf is computed from measured DPI, solving (14) directly leads to the value of γ. Since the value of C s and C g cannot be negative, so the value of γ should always be positive.…”

Research on automatic location and recognition of insulators in substation based on YOLOv3

“…It is a tremendous technological achievement to link the field and dispatching centre, effectively addressing the problems of low efficiency, poor real-time performance and the high risk coefficient of traditional electric power patrol inspection. It also promotes the development of intelligent and automatic electric power equipment detection [1][2][3].…”

Proposed methodology for online frequency response analysis based on magnetic coupling to detect winding deformations in transformers

“…A number of reliable offline methods of testing are available, such as frequency response analysis (FRA), transfer function (TF) analysis, short-circuit impedance (SCI) analysis, and low-voltage impulse testing [3][4][5][6][7]. Offline tests provide the freedom to perform reliable condition testing.…”