Hybrid numerical techniques for power transformer modeling: a comparative analysis validated by measurements

The paper presents alternative numerical techniques implemented in power transformer analysis and design focusing on the short circuit impedance evaluation. The proposed method adopts a particular reduced scalar potential formulation enabling a three-dimensional (3-D) magnetostatic problem solution. This method, requiring no source field calculation, in conjunction with a mixed finite-element/boundary-element technique, results in a very efficient 3-D numerical model for power transformer design office use. This model is used to develop an effective computational tool, enabling the accurate transformer characteristics prediction, thus increasing its reliability and reducing its production cost. The computed results of the proposed methodology are validated through measurements in the case of a three-phase wound core power transformer.

[1]  A. J. Moses.  Comparison Of Transformer Loss Predictions From Computed And Measured Flux Density Distributions , 1998 .

[2]  M. P. Papadopoulos,et al.  Leakage flux and force calculation on power transformer windings under short-circuit: 2D and 3D models based on the theory of images and the finite element method compared to measurements , 1994 .

[3]  N. D. Hatziargyriou,et al.  AI helps reduce transformer iron losses , 1999 .

[4]  B. Szabados,et al.  Three Dimensional Flux Calculation on a Three-Phase Transformer , 1986, IEEE Power Engineering Review.

[5]  Carlos Alberto Brebbia,et al.  The boundary element method for electromagnetic problems , 1987 .

[6]  Z. Feng.  The treatment of singularities in calculation of magnetic field by using integral method , 1985 .

[7]  A. Kladas,et al.  A new scalar potential formulation for 3-D magnetostatics necessitating no source field calculation , 1992 .

[8]  Cui Xiang,et al.  Analysis of leakage magnetic problems in shell-form power transformer , 1997 .

[9]  S. J. Salon,et al.  Hybrid finite element boundary element solutions for three dimensional scalar potential problems , 1986 .

[10]  M. Kuhn.  The application of coupled BE/FE formulations in technical magnetic field computations , 1998 .

[11]  J. D'Angelo,et al.  Applications of the hybrid finite element-boundary element method in electromagnetics , 1988 .

[12]  K. Zakrzewski,et al.  Magnetic field analysis and leakage inductance calculation in current transformers by means of 3-D integral methods , 1996 .

[13]  S. J. Salon,et al.  Comparison of assumptions in computation of short circuit forces in transformers , 2000 .

[14]  L. Pichon,et al.  Force calculation in axisymmetric induction devices using a hybrid FEM-BEM technique , 1990 .

[15]  Cui Xiang,et al.  Losses calculation in transformer tie plate using the finite element method , 1998 .

[16]  Stefanos Kollias,et al.  A novel iron loss reduction technique for distribution transformers based on a combined genetic algorithm - neural network approach , 2001 .