Recent Developments in the Modelling of Transformer Windings

Konstanty M. Gawrylczyk,Szymon Banaszak

doi:10.3390/en14102798

Konstanty M. Gawrylczyk, Szymon Banaszak

Open Access

https://doi.org/10.3390/en14102798

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Journal: Energies	Publication Date: May 13, 2021
Citations: 6	License type: CC BY 4.0

Affiliation: West Pomeranian University of Technology

Abstract

The paper provides a review of the modelling techniques used to simulate the frequency response of transformer windings. The aim of the research and development of modelling methods was to analyze the influence of deformations and faults in the windings on the changes in the frequency response. All described methods are given with examples of the modelling results performed by the authors of this paper and from literature sources. The research is prefaced with a thorough literature review. There are described models based on lumped parameters with input data coming from direct calculations based on the winding geometry and obtained from FEM modelling software and models considering the wave phenomena in the windings. The analysis was also performed for practical problems in winding modelling: the influence of windings other than the modelled one and the influence of parallel wires in a winding.

Highlights

Diagnostics plays an important role in the operation of power transformers
The analysis of frequency response measurement results is based on comparison of the data, which are usually presented as sine signal damping along the frequency spectrum in a logarithmic scale
Transformer models have been developed for years, finding many applications. They are used to determine the behavior of transformers under surge conditions and to interact with the power system or to analyze the frequency response used in diagnostics

Summary

Introduction

Diagnostics plays an important role in the operation of power transformers. It is based on many methods that, when properly applied, comprehensively define the technical condition of a given unit, especially in relation to their larger population; and, in combination with economic tools, they decide on planning for the future operation, renovation or replacement of a transformer. The analysis of frequency response measurement results is based on comparison of the data, which are usually presented as sine signal damping along the frequency spectrum in a logarithmic scale. Such a curve can be compared to the results recorded for a transformer in time intervals, between phases, between twin or sister units or with the help of computer models [5].

Transformer Modelling

Lumped Parameter Models Solved Using Circuit Simulators

Lumped Parameter Approach Based on Parameter Extraction from FEM

Distributed Parameter Approach—Wave Effects in Windings

Effect of Other Windings on the Same Core

Model of Windings Connected in Parallel

Summary and Future Work