Evaluation of the seismic performance of isolated electrical transformers under pulse-like excitations

Document Type : Research Article


1 Department of Civil Engineering, Faculty of Civil and Earth Resources Engineering, Central Tehran Branch, Islamic Azad University, Tehran, Iran

2 civil departement/ Engineering Faculty/ Central tehran Branch of Islamic Azad University/Tehran/Iran


Damage sustained by electrical transformers in past strong earthquakes led to irrecoverable and severe economic losses. The seismic performance evaluation is associated with the loss of proper functioning of the transformer. This study deals with modeling existing isolated electrical transformer structures to evaluate the effects of variables that may affect seismic performance and dynamic characteristics. The results probabilistically determine the seismic performance acceptability of study isolated electrical transformer structures based on the impact of key structural response parameters on the seismic performance of the transformer. Analyses of systems for a wide range of parameters are performed. The effects of horizontal and vertical near-fault pulse-like ground motions, the displacement capacity of the seismic isolation system, limit states of electrical bushings, and details of the isolation system design are considered. Also, the probability of failure of the transformer under near-fault excitations with pulse-like characteristics is investigated. The results of this study demonstrate that three-dimensional seismic isolation systems can improve the seismic performance for a wide range of parameters and can be further effective compared with only horizontal seismic isolation and offer the lowest probabilities of failure for all cases of transformer and isolation system parameters.


Main Subjects

[1] J. Wilcoski, S.J. Smith, Fragility Testing of a Power Transformer Bushing: Demonstration of CERL Equipment Fragility and Protection Procedure, DIANE Publishing, 1997.
[2] A. Gilani, A. Whittaker, G. Fenves, E. Fujisaki, Seismic evaluation of 550 kV porcelain transformer bearings, PEER Report, 5 (1999).
[3] A.S. Gilani, A.S. Whittaker, G.L. Fenves, Seismic evaluation and retrofit of 230-kV porcelain transformer bushings, Earthquake Spectra, 17(4) (2001) 597-616.
[4] A. Filiatrault, H. Matt, Experimental seismic response of high-voltage transformer-bushing systems, Earthquake Spectra, 21(4) (2005) 1009-1025.
[5] A.M. Reinhorn, K. Oikonomou, H. Roh, A. Schiff, J. Kempner, Modeling and seismic performance evaluation of high voltage transformers and bushings, MCEER, 2011.
[6] Y. Shumuta, K. Ishida, J. Tohma, A method for seismic retrofit planning of substation components on the basis of the cost benefit analysis, Doboku Gakkai Ronbunshu, 1998(584) (1998) 215-228.
[7] K. Oikonomou, H. Roh, A.M. Reinhorn, A. Schiff, L. Kempner, Seismic performance evaluation of high voltage transformer bushings, in:  Structures Congress 2010, 2010, pp. 2724-2735.
[8] K. Oikonomou, M.C. Constantinou, A.M. Reinhorn, L. Kempner Jr, Seismic isolation of high voltage electrical power transformers, MCEER Techincal Report MCEER-16, 6 (2016).
[9] A.S. Whittaker, G.L. Fenves, A.S. Gilani, Earthquake performance of porcelain transformer bushings, Earthquake Spectra, 20(1) (2004) 205-223.
[10] H. Suzuki, T. Sugi, H. Kuwahara, N. Kaizu, Studies on aseismic isolation device for electric substation equipment, in:  Developments in Geotechnical Engineering, Elsevier, 1987, pp. 347-357.
[11] S. Ersoy, M. Ala Saadeghvaziri, G.-Y. Liu, S. Mau, Analytical and experimental seismic studies of transformers isolated with friction pendulum system and design aspects, Earthquake Spectra, 17(4) (2001) 569-595.
[12] N. Murota, M.Q. Feng, G.Y. Liu, Earthquake simulator testing of base-isolated power transformers, IEEE transactions on power delivery, 21(3) (2006) 1291-1299.
[13] M. Koliou, A. Filiatrault, A.M. Reinhorn, Seismic response of high-voltage transformer-bushing systems incorporating flexural stiffeners I: Numerical study, Earthquake Spectra, 29(4) (2013) 1335-1352.
[14] S. Kitayama, D. Lee, M.C. Constantinou, L. Kempner Jr, Probabilistic seismic assessment of seismically isolated electrical transformers considering vertical isolation and vertical ground motion, Engineering Structures, 152 (2017) 888-900.
[15] D. Zou, L. Zhao, C. He, Q. Xie, Seismic Performance of±800 kV Ultra-High Voltage Converter Transformer-Bushing System, in:  2021 International Conference on Electrical Materials and Power Equipment (ICEMPE), IEEE, 2021, pp. 1-4.
[16] G.-L. Ma, Q. Xie, A. Whittaker, Seismic performance assessment of an ultra-high–voltage power transformer, Earthquake Spectra, 35(1) (2019) 423-445.
[17] L. Shen, H. Li, Y. Duan, Y. Zhang, J. Wen, Q. Xie, Seismic Performance and Vulnerability Analysis of High Voltage Capacitor, in:  2021 Power System and Green Energy Conference (PSGEC), IEEE, 2021, pp. 604-609.
[18] S. Kitayama, M.C. Constantinou, D. Lee, Procedures and results of assessment of seismic performance of seismically isolated electrical transformers with due consideration for vertical isolation and vertical ground motion effects, MCEER-16-0010 Report,  (2016) 180.
[19] A.T. Council, Quantification of building seismic performance factors, US Department of Homeland Security, FEMA, 2009.
[20] A.S.o.C. Engineers, Minimum design loads and associated criteria for buildings and other structures, in, American Society of Civil Engineers, 2017.
[21] S. Kitayama, M.C. Constantinou, Performance evaluation of seismically isolated buildings near active faults, Earthquake Engineering & Structural Dynamics, 51(5) (2022) 1017-1037.
[22] S. Kitayama, M.C. Constantinou, Probabilistic seismic performance assessment of seismically isolated buildings designed by the procedures of ASCE/SEI 7 and other enhanced criteria, Engineering Structures, 179 (2019) 566-582.
[23] H. Cilsalar, M.C. Constantinou, Behavior of a spherical deformable rolling seismic isolator for lightweight residential construction, Bulletin of Earthquake Engineering, 17(7) (2019) 4321-4345.
[24] D. Vamvatsikos, C.A. Cornell, Incremental dynamic analysis, Earthquake engineering & structural dynamics, 31(3) (2002) 491-514.
[25] T. Anagnos, Development of an electrical substation equipment performance database for evaluation of equipment fragilities, Citeseer, 1999.
[27] Ostrom D. SERAII. Advancing mitigation technologies and disaster response for lifeline systems, ASCE, pp. 587–596, 2003.
[28] D. Ostrom, Database of seismic parameters of equipment in substations. Report to pacific earthquake engineering research center, in, 2004.
[29] M. Kumar, A.S. Whittaker, M.C. Constantinou, Characterizing friction in sliding isolation bearings, Earthquake Engineering & Structural Dynamics, 44(9) (2015) 1409-1425.
[30] C.B. Haselton, Assessing seismic collapse safety of modern reinforced concrete moment frame buildings, Stanford University, 2006.
[31] C.B. Haselton, A.B. Liel, B.S. Dean, J.H. Chou, G.G. Deierlein, Seismic collapse safety and behavior of modern reinforced concrete moment frame buildings, in:  Structural engineering research frontiers, 2007, pp. 1-14.
[32] C.B. Haselton, C.A. Goulet, J. Mitrani-Reiser, J.L. Beck, G.G. Deierlein, K.A. Porter, J.P. Stewart, E. Taciroglu, An assessment to benchmark the seismic performance of a code-conforming reinforced-concrete moment-frame building, Pacific Earthquake Engineering Research Center, (2007/1) (2008).
[33] A.B. Liel, C.B. Haselton, G.G. Deierlein, Seismic collapse safety of reinforced concrete buildings. II: Comparative assessment of nonductile and ductile moment frames, Journal of Structural Engineering, 137(3) (2011) 492-502.
[34] D. Lignos, H. Krawinkler, Sidesway collapse of deteriorating structural systems under seismic excitations. Report No. TB 172, John A. Blume Earthquake Engineering Research Center, Department of Civil and Environmental Engineering, Department of Civil and Environmental Engineering, 72 (2009) 1-12.
[35] R.A. Medina, H. Krawinkler, Influence of hysteretic behavior on the nonlinear response of frame structures, in:  13th world conference on earthquake engineering, 2004.
[36] Institute of Electrical and Electronics Engineers (IEEE). “IEEE Recommended Practice for Seismic Design of Substations, IEEE Standard 693.” IEEE Power Engineering Society, The Institute of Electrical and Electronics Engineers, Inc. New York, NY,(2018).
[37] M. Shinozuka, X. Dong, T. Chen, X. Jin, Seismic performance of electric transmission network under component failures, Earthquake engineering & structural dynamics, 36(2) (2007) 227-244.
[38] Kempner L. Jr. Eidinger J. Perez J. Schiff A.. “Seismic Risk of High Voltage Electric Transmission Network.” 8th U.S. National Conference on Earthquake Engineering, April 18-22, San Francisco, CA, (2006).
[39] D. Lee, M.C. Constantinou, Combined horizontal–vertical seismic isolation system for high-voltage–power transformers: development, testing and validation, Bulletin of earthquake engineering, 16(9) (2018) 4273-4296.
[40] Lee D, Constantinou MC .Combined Horizontal-Vertical Seismic Isolation System For High-Voltage Power Transformers. MCEER-17-0007 2017; Multidisciplinary Center for Earthquake Engineering Research, Buffalo,NY, (2017).
[41] Y. Shumuta, Practical seismic upgrade strategy for substation equipment based on performance indices, Earthquake engineering & structural dynamics, 36(2) (2007) 209-226.
[42] D. Kong, Evaluation and protection of high voltage electrical equipment against severe shock and vibrations, State University of New York at Buffalo, 2010.
[43] M. Fahad, Seismic evaluation and qualification of transformer bushings, State University of New York at Buffalo, 2013.
[44] R. Villaverde, G.C. Pardoen, S. Carnalla, Ground motion amplification at flange level of bushings mounted on electric substation transformers, Earthquake engineering & structural dynamics, 30(5) (2001) 621-632.
[45] D. Fenz, M. Constantinou, Development, Implementation, and Verification of Dynamic Analysis Models for Multi-spherical Sliding Bearings, Technical Report MCEER-08-0018, in, Multidisciplinary Center for Earthquake Engineering Research, State …, 2008.
[46] A. Sarlis, M. Constantinou, A. Reinhorn, Shake Table Testing of Triple Friction Pendulum Isolators under Extreme Conditions 13-0011. pdf, (2013).
[47] F.T. McKenna, Object-oriented finite element programming: frameworks for analysis, algorithms and parallel computing, University of California, Berkeley, 1997.
[48] W.J. McVitty, M.C. Constantinou, Property modification factors for seismic isolators: design guidance for buildings, MCEER report, (2015) 15-0005.
[49] PEER NGA WEST 2 <http://ngawest2.berkeley.edu/> [9 November 2015].
[50] S. Abdonnabi Razavi, N. Siahpolo, M. Mahdavi Adeli, A New Empirical Correlation for Estimation of EBF Steel Frame Behavior Factor under Near-Fault Earthquakes Using the Genetic Algorithm, (2020).
[51] A. Khansefid, Pulse-like ground motions: Statistical characteristics, and GMPE development for the Iranian Plateau, Soil Dynamics and Earthquake Engineering, 134 (2020) 106164.
[52] P.G. Somerville, Magnitude scaling of the near fault rupture directivity pulse, Physics of the earth and planetary interiors, 137(1-4) (2003) 201-212.
[53] Y.-N. Huang, A.S. Whittaker, N. Luco, Maximum spectral demands in the near-fault region, Earthquake Spectra, 24(1) (2008) 319-341.