Improvement of power transformer differential protection through detection and exploitation of the negative sequence currents




power transformer, diagnosis, inter turn faults, symmetrical components, negative sequence currents


Introduction. Power transformers are the most important and the most expensive equipment used in transport and distribution of electrical energy. Their failure results in huge economic losses. Despite the great advances in the design of power equipment in recent years, the feeble link in the chain remains the insulation weakness of coil turns of the power transformer. The novelty of the proposed research consists in the development of a new procedure for diagnosing and localizing the occurrence of turn to turn short-circuits in the windings of three-phase power transformer. The main problems of the current differential relay are short circuits of one or more turns of a transformer winding. Hence a new approach using' the amplitude comparison between the negative sequence currents' is developed and a digital discriminator internal / external fault is applied to discriminate turn to turn faults among the other ones. The proposed procedure is based on the exploitation of the negative sequence currents. The purpose of using this new procedure is to identify small faults inside power transformer coils and to distinguish inner faults from the outer faults by using an ameliorate circuit. The method used in this paper is a novel algorithm which based on the comparison between the negative sequence current amplitudes and to calculate the corresponding phase angle shifts. The performance of the proposed procedure has been confirmed by MATLAB/Simulink environment. The results of simulation reveal the efficiency of the suggested procedure, and indicate that this procedure can provide fast and sensitive approach for detecting low level turn-to-turn faults.

Author Biography

M. Zitouni, University of Setif

PhD Student, Associate lecturer, Electrical Engineering Department, Automatic Laboratory


Blackburn J.L. Applied protective relaying. Westinghouse Electric Corporation. Relay Instrument Division. 2nd ed., 1979.

Summary of the «Guide for Protective Relay Applications to Power Transformers» ANSI C37.91. IEEE Transactions on Power Apparatus and Systems, 1985, vol. PAS-104, no. 12, pp. 3538-3543. doi:

Lapworth J., McGrail T. Transformer failure modes and planned replacement. IEE Colloquium on Transformer Life Management (Ref. No. 1998/510), 1998, pp. 9/1-9/7. doi:

IEEE Guide for Protective Relay Applications to Power Transformers. IEEE Std C37.91-2000 (Revision of IEEE Std C37.91-1985), 2000, pp. 1-85. doi:

IEEE Guide for the Protection of Network Transformers. IEEE Std C37.108-2002 (Revision of C37.108-1989), 2002, pp. 1-40. doi:

Faiz J., Heydarabadi R. Diagnosing power transformers faults. Russian Electrical Engineering, 2014, vol. 85, no. 12, pp. 785-793. doi:

Aljohani O., Abu-Siada A. Application of Digital Image Processing to Detect Short-Circuit Turns in Power Transformers Using Frequency Response Analysis. IEEE Transactions on Industrial Informatics, 2016, vol. 12, no. 6, pp. 2062-2073. doi:

Torkaman A., Naeini V. Recognition and location of power transformer turn to turn fault by analysis of winding imposed forces. Journal of Operation and Automation in Power Engineering, 2019, vol. 7, no. 2, pp: 227-234. doi:

Sachdev M.S., Sidhu T.S., Wood H.C. A digital relaying algorithm for detecting transformer winding faults. IEEE Transactions on Power Delivery, 1989, vol. 4, no. 3, pp. 1638-1648. doi:

Chavhan R., Kulkarni V.A. Negative sequence component for detection of inter-turn fault of transformer. International Journal of Innovative Research in Science, Engineering and Technology, 2017, vol. 6, no. 7, pp. 13950-13958. Available at: (accessed 13 May 2021).

Zacharias D., Gokaraju R. Prototype of a Negative-Sequence Turn-to-Turn Fault Detection Scheme for Transformers. IEEE Transactions on Power Delivery, 2016, vol. 31, no. 1, pp. 122-129. doi:

Ngaopitakkul A., Kunakorn A. Internal fault classification in transformer windings using combination of discrete wavelet transforms and back-propagation neural networks. International Journal of Control, Automation and Systems, 2006, vol. 4, no. 3, pp. 365-371. Available at: (accessed 13 May 2021).

Devadiga A.A., Harid N., Griffiths H., Al Sayari N., Barkat B., Jayaram S., Ikeda H., Koshizuka T., Taniguchi Y. Winding turn-to-turn short-circuit diagnosis using FRA method: sensitivity of measurement configuration. IET Science, Measurement & Technology, 2019, vol. 13, no. 1, pp. 17-24. doi:

Stavinskiy A.A., Tsyganov A.M. Design and technological proposals for improving a single-phase transformer with laminated magnetic core. Electrical Engineering & Electromechanics, 2020, no. 6, pp. 11-17. doi:

Rizvi I.A., Reeser G. Using symmetrical components for internal external fault discrimination in differential protection schemes. 2013 66th Annual Conference for Protective Relay Engineers, 2013, pp. 68-79. doi:

Subramanian M. Detection of winding inter-turn faults. Detection based on frequency response analysis - Part I. Transformers Magazine, 2020, vol. 7, iss. 1, pp. 112-118. Available at: (accessed 13 May 2021).

Panah M.S.P., Azarakhsh J., Raisi Z. A novel method in differential protection of power transformer using wavelet transform and correlation factor analysis. Bulletin de la Societe Royale des Sciences de Liege, 2016, vol. 85, p. 1119-1135. doi:

Ivanchenko D., Smirnov A. Identification of interturn faults in power transformers by means of generalized symmetrical components analysis. E3S Web of Conferences, 2019, vol. 140, p. 04007. doi:

Azizan N.S., Wooi C.L., Ismail B., Arshad S.N.M., Isa M., Mustafa W.A., Rohani M. Simulation of differential relay for transformer protection. IOP Conference Series: Materials Science and Engineering, 2020, vol. 767, p. 012004. doi:

Syvokobylenko V.F., Lysenko V.A. Improving the efficiency of fault protection systems of electrical grids based on zero sequence voltages and currents wavelet transforms. Electrical Engineering & Electromechanics, 2020, no. 4, pp. 67-72. doi:

Snitkov K.I., Shabatura Y.V. A method of reducing the error in determining the angular displacements when using inductive sensors. Electrical Engineering & Electromechanics, 2020, no. 6, pp. 3-10. doi:

Liu C.-H., Muda W.H.P., Kuo C.-C. Turn-to-Turn Fault Diagnosis on Three-Phase Power Transformer Using Hybrid Detection Algorithm. Applied Sciences, 2021, vol. 11, no. 6, p. 2608. doi:




How to Cite

Zitouni, M. (2022). Improvement of power transformer differential protection through detection and exploitation of the negative sequence currents. Electrical Engineering & Electromechanics, (1), 12–20.



Electrical Machines and Apparatus