A Novel Approach of Power Transformer Diagnostic Using 3D FEM Parametrical Model

This paper deals with a novel approach of power
transformers diagnostics. This approach identifies the exact location
and the range of a fault in the transformer and helps to reduce
operation costs related to handling of the faulty transformer, its
disassembly and repair. The advantage of the approach is a
possibility to simulate healthy transformer and also all faults, which
can occur in transformer during its operation without its
disassembling, which is very expensive in practice. The approach is
based on creating frequency dependent impedance of the transformer
by sweep frequency response analysis measurements and by 3D FE
parametrical modeling of the fault in the transformer. The parameters
of the 3D FE model are the position and the range of the axial short
circuit. Then, by comparing the frequency dependent impedances of
the parametrical models with the measured ones, the location and the
range of the fault is identified. The approach was tested on a real
transformer and showed high coincidence between the real fault and
the simulated one.





References:
[1] M. Brandt, P. Rafajdus, A. Peniak, J. Michalik: Diagnostics system
ofpower transformers supported by Finite Element Analysis,
SPEEDAM2012, Sorrento (Italy) , June 20-22, 2012, p.: 806-811, IEEE
Xplore, ISBN 978-1-4673-1300-1
[2] M. Koch, S. Raetzke, M. Kreuger: Moisture diagnostics of power
transformers by a fast and reliable dielectric response method Electrical
Insulation (ISEI), Conference Record of the 2010 IEEE International
Symposium, Page(s): 1 - 5
[3] V. Mentlik, P. Prosr, J. Pihera, R. Polansky, P. Trnka: On-line
diagnostics of power transformers, Conference Record of the 2006 IEEE
International Symposium on Electrical Insulation (IEEE Cat. No.
06CH37794),Page(s): 546 549
[4] U. S. Department of the Interior bureau of reclamation: Transformer
Diagnostic, FIST 3-31, June 2003
[5] S.A. Ryder: Diagnosing Transformer Faults Using Frequency Response
Analysis, IEEE Electrical Insulation Magazine, 0883-7554/03, IEEE
2003
[6] S. M. Islam, K. M. Coates, G. Ledwich: Identification of High
Frequency Transformer Equivalent Circuit Using Matlab from
Frequency Domain Data, Industry Applications Conference, pages: 357-
364, 1997, ISBN 0-7803-4067-1.
[7] N. Abeywickrama, Student Member, Y. V. Serdyuk, S. M. Gubanski:
High-Frequency Modeling of Power Transformers for Use in Frequency
Response Analysis (FRA), IEEE Transactions on Power Delivery23,
pages: , 2008
[8] T.Y. Ji, W.H. Tang, Q.H. Wu: Detection of power transformer winding
deformation and variation of measurement connections using a hybrid
winding model, Electric Power Systems Research 87, pages: 39-46, 2012
[9] E. Rahimpour, J. Christian, K. Feser, H. Mohseni: Transfer Function
Method to Displacement and Radial Deformation of Transformer
Windings, IEEE Transactions on Power Delivery 18, pages: 493-505,
2003
[10] E. Bjerkan: High Frequency Modelling of Power Transformers: Stresses
and Diagnostics, Ph.D. dissertation, Norwegian Univ. Sci. and Technol.,
Trondheim, Norway, 2005.
[11] M. Brandt, R. Seewald, J. Sedlk, D. Faktorov: Measurement andanalysis
of railway traction transformer using by SFRA method part
2,Diagnostika 11, published by University of West Bohemia, 2011,
ISBN978-80-261-0020-1
[12] Jezierski: Transformtory - Teoretick zklady, Academia Praha, 1973,
ISBN509-21-875