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A Modified Current Differential Relay for Transformer Protection  

강용철 (전북대 전자정보공학부)
김은수 (전북대 전자정보공학부)
원성호 (전북대 전자정보공학부)
Publication Information
The Transactions of the Korean Institute of Electrical Engineers A / v.53, no.2, 2004 , pp. 80-86 More about this Journal
Abstract
During magnetic inrush or over-excitation, saturation of the core in a transformer draws a large exciting current, which can cause mal-operation of a differential relay. This paper proposes a modified current differential relay for transformer protection. The relay calculates core-loss current from the induced voltage and the core-loss resistance; the relay calculates the magnetizing current from the core flux and the magnetization curve. Finally, the relay obtains the modified differential current by subtracting the core-loss and the magnetizing currents from the conventional differential current. Comparison study with the conventional differential relay with harmonic blocking is also shown. The proposed technique not only discriminates magnetic inrush and over-excitation from an internal fault, but also improves the speed of the conventional relay.
Keywords
Magnetizing current; Core-loss current; Magnetic inrush; Overexcitation; Harmonic blocking;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 /
[] / Electrimagnetic Transients Program Theory Book
2 A Digital Relaying Algorithm for Detecting Transformer Winding Faults /
[ M.S.Sachdev ] / IEEE Trans. on PWRD
3 A Transformer Protective Realying Algorithm Using the Fatio of Indyced Voltages /
[ Y.C.Kang;B.E.Lee;S.H.Kang;S.S.Kim;J.K.Lee ] / IEEE PES 2001 SM
4 C. H. Einvall, and J. R. Linders, 'A Three-phase Differential Realy for Transformaer Protection,' IEEE Trans. on PAS, vol 94, no. 6, pp. 1971-1980, Nov/Dec. 1975   DOI
5 A Transfprmer Model for Winding Fault Studies /
[ P.Bastard;P.Bertrand;M.Meunier ] / IEEE Trans. on PWRD
6 C. W. Mathews, 'An improved transformer differential relay,' AIEE Trans. Part III, vol. 73, pp. 645-650, Jun. 1954
7 C. D. Hayward, 'Harmonic-Current-Restrained Relays for Transformer Differential Protection,' AIEE Trans. vol. 60, pp. 377-382, 1941
8 A. Giulinte, and G. Dlough, 'Advances in the design of differential protection for power transformers,' 1991 Georgia Tech. Protective Relaying Conference, Atlanta, GA, May 13, 1991, pp. 1-12
9 A. G. Phadke, and J. S. Thorp, Computer Relaying for Power Systems, Reserarcg Studies Press LTD., 1988
10 R. L. Sharp, and W. E. Glassburn, 'A Transformer Differential Relay with Second-Harmonic Restraint,' AIEE Trans. Part III, vol. 77, pp. 913-918, 1958
11 G. D. Rockefeller, 'Fault Protection with a Digital Computer,' IEEE Trans. on PAS, vol. 88, no. 4, pp. 438-462, Apr. 1969   DOI   ScienceOn
12 E. L. Harder, and W. E. Marter, 'Pronciples and practices of relaying in the United States,' AIEE Trans. Pat II, vol. 67, pp. 1005-1022, 1948
13 Electrimagnetic Transients Program Theory Book Chapter 2, 1986
14 A. G. Phadke, and J. S. Thorp, 'A New Computer-Based Flux-Restrained Current Differential Relay for Power Transformer Protection,' IEEE Trans. on PAS, vol.102, no. 11, pp. 3624-3629, Nov. 1983   DOI   ScienceOn
15 K. Inagaki, M. Higaki, Y. Matsui, K. Kurita, M. Suzuki, K. Yoshida, and T. Maeda, 'Digital Protection Method for Power Transformers Based on an Equivalent Circuit Composed of Inverse Imductance,' IEEE Trans. on PWRD, vol. 3, no. 4, pp. 1501-1510, Oct. 1988   DOI   ScienceOn
16 Y. C. Kang, B. E. Lee, S. H. Kang, S. S. Kim, and J. K. Lee, 'A Transformer Protective Realying Algorithm Using the Fatio of Indyced Voltages,' IEEE PES 2001 SM, July 1519, 2001, Vancouver, BC Canada   DOI
17 P. Bastard, P. Bertrand, and M. Meunier, 'A Transfprmer Model for Winding Fault Studies,' IEEE Trans. on PWRD, vol. 9, no. 2, pp. 690-699 Apr. 1994   DOI   ScienceOn
18 M. S. Sachdev, T. S. Sidhu, and H. C. Wood, 'A Digital Relaying Algorithm for Detecting Transformer Winding Faults,' IEEE Trans. on PWRD, vol. 4, no. 3, pp. 1638-1348, Jul. 1989   DOI   ScienceOn