Effect of Wormhole Defects on Electric Field Distribution under Composite Voltage
Year 2025,
Volume: 8 Issue: 5, 1561 - 1576, 15.09.2025
Emre Tunç
,
Murat Fidan
Abstract
The reliability of electrical insulation systems is critical to the continuity of energy transmission and distribution systems. Structural defects that occur in polymer-based insulating materials can affect the distribution of electric fields, leading to partial discharges and subsequently serious failures such as breakdowns. In this study, the effects of wormhole structures with different diameters in cross-linked polyethylene (XLPE) insulators on electric field distribution under alternating current (AC), direct current (DC), and composite voltage (AC+DC) components were numerically investigated using COMSOL Multiphysics software. In the system modeled under a needle-plane electrode configuration, significant increases in both volumetric and surface electric field intensities were observed as the diameter of the wormhole increased. Among all cases, composite voltage conditions resulted in the highest field concentrations, indicating increased electrical stress on the insulation. Additionally, higher field intensities were observed under negative polarity than under positive polarity in all cases. The findings highlight the importance of considering wormhole-type defects in the design of insulating systems and analyzing the electrical stress caused by composite voltage conditions.
Ethical Statement
Ethics committee approval was not required for this study because of there was no study on animals or humans.
References
-
Adhikari P, Ghassemi M. 2024. Navigating strategies to mitigate insulation issues within high power density (U)WBG power module packages: A comprehensive review emphasizing alternative encapsulation materials. IEEE Transact Industry Applicat, 2024: 1–22. https://doi.org/10.1109/tia.2024.3520096
-
Annadi RR, Patsa CS. 2020. Estimation of switching surge flashover rate of 1200-kV UHVAC transmission line considering switching overvoltage waveshape. Electr Eng, 102(2): 953–966. https://doi.org/10.1007/s00202-020-00918-7
-
Beroual A, Dang V-H, Perrier C. 2013. Investigation on creeping discharges propagating over pressboard immersed in mineral and vegetable oils under AC, DC and lightning impulse voltages. IEEE Trans Dielectr Electr Insul, 20(5): 1-6.
-
Borghei M, Ghassemi M. 2022. Separation and classification of corona discharges under low pressures based on deep learning method. IEEE Trans Dielectr Electr Insul, 29(1): 319–326. https://doi.org/10.1109/TDEI.2022.3146608
-
Chen Q, Wu Z, Liu F, Yun F, Liu D, Fan J, … Gao C. 2022. The discharge mode of SF6N2Gas mixture in extremely inhomogeneous electric field under power frequency voltage. Conference on Electrical Insulation and Dielectric Phenomena, CEIDP, 13-16 November, pp: 560–563. Institute of Electrical and Electronics Engineers Inc. https://doi.org/10.1109/CEIDP55452.2022.9985344
-
Chen S, Li K, Wang F, Sun Q, Zhong L. 2019. Effect of humidity and air pressure on the discharge modes transition characteristics of negative DC corona. IET Sci Meas Technol, 13(8): 1212–1218. https://doi.org/10.1049/iet-smt.2019.0032
-
Dedeoglu S, Merev A. 2023. Realization of the reference composite voltage waveforms for lightning impulse (LI) voltages superimposed over DC and AC signals. Mapan J Metrol Soc India, 38(3): 597–606. https://doi.org/10.1007/s12647-023-00634-0
-
Dissado LA, Fothergill JC. 1992. Electrical degradation and breakdown in polymers (1st ed.). Institution of Engineering and Technology. London, UK, pp: 54-98.
-
Dong W, Wang X, Tian B, Liu Y, Jiang Z, Li Z, Zhou W. 2019. Use of grafted voltage stabilizer to enhance dielectric strength of cross-linked polyethylene. Polymers, 11(1): 1-6. https://doi.org/10.3390/POLYM11010176
-
Dordizadeh P, Adamiak K, Castle GSP. 2017. Experimental study of the characteristics of Trichel pulses in the needle-plane negative corona discharge in atmospheric air. J Electrostat, 88: 49–54. https://doi.org/10.1016/j.elstat.2016.12.013
-
Fidan M, Ismailoglu H. 2017. Harmonik kaynaklı gerilim bozulmalarının elektriksel kısmi boşalmalar üzerindeki etkilerinin incelenmesi. J Fac Eng Archit Gazi Univ, 32(3): 929–939. https://doi.org/10.17341/gazimmfd.337646
-
Freitas-Gutierres LF, Maresch K, Morais AM, Nunes MVA, Correa CH, Martins EF, … Oliveira AL. 2024. Framework for decision-making in preventive maintenance: Electric field analysis and partial discharge diagnosis of high-voltage insulators. Electr Power Syst Res, 233: 1-6. https://doi.org/10.1016/j.epsr.2024.110447
-
Ghassemi M. 2018. PD measurements, failure analysis, and control in high‐power IGBT modules. High Volt, 3(3): 170–178. https://doi.org/10.1049/hve.2017.0186
-
Gong M, Lu M, Liu H, Jiang H, Sun QF, Xie XC. 2020. Transport study of the wormhole effect in three-dimensional topological insulators. Phys Rev B, 102(16): 1-6. https://doi.org/10.1103/PhysRevB.102.165425
-
Hamidieh M, Ghassemi M. 2024. Conic cross-sectional electrodes and their influence on negative corona discharge and trichel pulse characteristics. IEEE Trans Dielectr Electr Insul, 31(4): 2064–2073. https://doi.org/10.1109/TDEI.2024.3385751
-
Hu K, Li G, Gu Z, Zhang F, Wei Y, Lei Q. 2023. Analysis of influence factors on ac breakdown characteristics of rod-barrier gap and electric field simulation. J Electr Eng Technol, 18(3): 2189–2197. https://doi.org/10.1007/s42835-022-01259-0
-
IEC 60060-1:2010. High-voltage test techniques - Part 1: General definitions and test requirements. 2010: 68.
-
Ispirli MM, Kalenderli Ö, Seifert F, Rock M, Oral B. 2022b. Investigation of impact of DC component on breakdown characteristics for different electric fields under composite AC and DC voltage. High Volt, 7(2): 279–287. https://doi.org/10.1049/hve2.12185
-
Ispirli MM, Oral B, Kalenderli Ö. 2022a. Electric field analysis of 66 kV and 110 kV SiR insulators under combined AC–DC voltages. Energy Rep, 8: 361–368. https://doi.org/10.1016/j.egyr.2021.11.149
-
Kadim EJ, Noorden ZA, Adzis Z, Azis N. 2021. Nanoparticles application in high voltage insulation systems. IEEE Trans Dielectr Electr Insul, 28(4): 1380–1399. https://doi.org/10.1109/TDEI.2021.009531
-
Kavanagh DF, Gyftakis KN, Mcculloch MD. 2020. Thermal degradation phenomena of polymer film on magnet wire for electromagnetic coils. IEEE Trans Ind Appl, 57(1): 458–467. https://doi.org/10.1109/TIA.2020.3040201
-
Küchler A. 2017. High voltage engineering. Springer eBooks, London, UK, pp: 168. https://doi.org/10.1007/978-3-642-11993-4
-
Lan G, Bo L, Huanchao C, Jinzhong Li. 2012. Breakdown characteristics of typical model in transformer oil under AC and DC mixed voltage. 2012 October 14–17, 2012 Annual Report Conference on Electrical Insulation and Dielectric Phenomena. IEEE, Ottawa, Canada, pp: 68.
-
Li Y, Zhang Q, Zhao Y, Wang T, Liu G, Wang K. 2017. The influence of temperature on Partial Discharges and wormhole effect of oil-paper insulation under DC voltage. 2017 June 11–14 IEEE Electrical Insulation Conference (EIC). IEEE, Montreal, Canada.
-
Li Y, Zhou K, Zhu GY, Zhang QG. 2019. Effect of DC discharges in mineral oil on degradation characteristics of oil-impregnated pressboard. IEEE Trans Dielectr Electr Insul, 26(5): 1701–1708. https://doi.org/10.1109/TDEI.2019.008256
-
Li Z, He D, Ren F, Li S, Wu H, Sun Y, … Li Q. 2025. Effect of temperature on the internal electric field distribution and discharge mechanism of converter transformer under AC–DC composite voltage. IEEE Trans Dielectr Electr Insul, 32(2): 1084–1093. https://doi.org/10.1109/TDEI.2024.3435815
-
Liang H, Du B, Li J. 2020. Non-Intrusive measurement of transient electric field distribution under AC and impulse voltages. IEEE Sens J, 20(18): 10898–10902. https://doi.org/10.1109/JSEN.2020.2994246
-
Lin L, Meng X, Mei H, Wang L. 2024. Influence of AC and DC composite voltage on positive streamer discharge. IEEE Trans Dielectr Electr Insul, 31(2): 779–785. https://doi.org/10.1109/TDEI.2023.3325421
-
Liu L, Zhang Z, Peng Z, Ouyang J. 2013. Comparison of point-to-plane corona in different gases. J Phys Conf Ser, 418(1): 1-6. Institute of Physics Publishing. https://doi.org/10.1088/1742-6596/418/1/012092
-
Muppala P, Reddy CC. 2021. Electric field and DC breakdown voltage of multi-layer dielectrics in parallel-plane geometry. IEEE Trans Dielectr Electr Insul, 28(1): 257–265. https://doi.org/10.1109/TDEI.2020.008830
-
Negari S, Moghadam DE. 2024. A novel approach towards parametric assessment of reliability and resilience of high voltage mica-based insulation systems by statistical analysis of experimental failure data. High Volt, 9(2): 495–507. https://doi.org/10.1049/hve2.12431
-
Özkaya M. 2008. Yüksek gerilim tekniği. Birsen Yayınevi, Cilt I, İstanbul, Türkiye, ss: 68.
-
Park C, Lee K, Kim K, Lim H, Park Y. 2024. Evaluation of Time-Based arc flash detection with non-contact UV sensor. J Electr Eng Technol, 19(3): 1983–1992. https://doi.org/10.1007/s42835-023-01555-3
-
Qiu Z, Ruan J, Huang D, Pu Z, Shu S. 2015. A prediction method for breakdown voltage of typical air gaps based on electric field features and support vector machine. IEEE Trans Dielectr Electr Insul, 22(4): 2125–2135. https://doi.org/10.1109/TDEI.2015.004887
-
Reddy BST, Wani SA, Amizhtan SK, Naresh C, Sarathi R. 2023. Understanding the surface discharge activity with nano oil-pressboard insulation under AC and lightning impulse voltages. IEEE Trans Dielectr Electr Insul, 31(2): 889–896. https://doi.org/10.1109/TDEI.2023.3334245
-
Roggendorf C, Schnettler A. 2012. Accelerated hydrothermal aging of epoxy resin based syntactic foams with polymeric microspheres. IEEE Trans Dielectr Electr Insul, 19(3): 973–980. https://doi.org/10.1109/TDEI.2012.6215102
-
Rosenberg G, Guo HM, Franz M. 2010. Wormhole effect in a strong topological insulator. Phys Rev B, 82(4): 1-6. https://doi.org/10.1103/PhysRevB.82.041104
-
Rubinetti D, Iranshahi K, Onwude DI, Nicolaï BM, Xie L, Defraeye T. 2024. Energy-saving discharge needle shape for electrohydrodynamic airflow generation. J Electrostat, 127: 1-6. https://doi.org/10.1016/j.elstat.2023.103876
-
Saini S, Prasad SD. 2024. Quasi-static ac surface charging of polymeric insulators at low pressure. IEEE Trans Ind Appl, 60(4): 5663–5670. https://doi.org/10.1109/TIA.2024.3397773
-
Stone G, Boulter EA, Culbert I, Dhirani H. 2014. Electrical insulation for rotating machines. Design, Evaluation, Aging, Testing, and Repair, London, UK, pp:59-67.
-
Tian H, Liu L, Guo Z, Wang H, Shi R, Peng Z. 2017. Research on electrical field distribution of tri-post insulator and distortion effect by defects. 2017 IEEE Conference on Electrical Insulation and Dielectric Phenomenon (CEIDP). IEEE, 22-25 October, Fort Worth, Texas, USA, pp: 82.
-
Timoshkin IV, Given MJ, Macgregor SJ, Wilson MP, Lehr JM. 2009. Pre-breakdown currents in insulating liquids stressed with non-uniform DC electric field. 2009 June 12–14 IEEE Pulsed Power Conference, Washington DC, USA, pp: 63.
-
Tunç E, Fidan M. 2023. Residual voltage tests of 4.5 kV metal oxide surge arrester. 14th International Conference on Electrical and Electronics Engineering, ELECO 2023 - Proceedings. November 30-December 2, Bursa, Türkiye, pp: 18. https://doi.org/10.1109/ELECO60389.2023.10415938
-
Wu Z, Xu H, Zhou J, Chen Y, Zhang Z, Zhang Q. 2024. Accumulative effect of bipolar oscillation impulse voltage on interturn insulation of transformer winding. IEEE Trans Dielectr Electr Insul, 32(2): 1-6. https://doi.org/10.1109/TDEI.2024.3446768
-
Yang Y, Gao K, Bi J, Ding L, Yuan S, Wang G. 2022. Influence of micro-water on AC breakdown characteristics of C4F7N/CO2 gas mixture under non-uniform electric field. High Volt, 7(6): 1059–1068. https://doi.org/10.1049/hve2.12215
-
Zhang B, Ghassemi M, Zhang Y. 2021. Insulation materials and systems for power electronics modules: A review identifying challenges and future research needs. IEEE Trans Dielectr Electr Insul, 28(1): 290–302. https://doi.org/10.1109/TDEI.2020.009041
-
Zhao L, Su J, Zhang X, Pan Y, Wang L, Fang J, … Cheng J. 2013. An experimental and theoretical investigation into the “wormhole” effect. J Appl Phys, 114(6): 1-6. https://doi.org/10.1063/1.
-
Zhao L. 2022. A unified formula for five basic forms of discharge in an electric field under short pulses. IEEE Trans Plasma Sci, 50(10): 3400–3411. https://doi.org/10.1109/TPS.2022.3169602
-
Zhao T, Liu Y, Liu Y, Yang C, Zheng Y, Zhu W, Gu Z. 2024. Bubble motion characteristics in the transformer oil gap at the top of HV Winding. IEEE Transact Dielectrics Electrical Insulat, 1: 3361848. https://doi.org/10.1109/tdei.2024.3361848
-
Zhao X, Li B, Xiao D, Deng Y. 2017. Breakdown characteristics of CF3I-N2 gas mixtures in a needle-plate geometry. IEEE Transact Dielectrics Electrical Insulation, 24(2): 869–875. https://doi.org/10.1109/tdei.2017.006089
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Zheng Y, Zhao T, Tong Y, Chao N. 2021. Simulation of the movement characteristics of micro-bubbles in the oil gap of transformer. 2021 Electrical Insulation Conference, EIC 2021, June 7-28, online, pp: 141–144. https://doi.org/10.1109/EIC49891.2021.9612265
-
Zhou Y, Huang X, Zhang L, Zhang Y, Zhou Z, Teng C, . . . Huang M. 2020. Space charge characteristics of oil-paper under AC/DC composite voltage. 2022 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP), September 14-17, Manchester, United Kingdom, pp: 308–311. https://doi.org/10.1109/ceidp49254.2020.9437530
Effect of Wormhole Defects on Electric Field Distribution under Composite Voltage
Year 2025,
Volume: 8 Issue: 5, 1561 - 1576, 15.09.2025
Emre Tunç
,
Murat Fidan
Abstract
The reliability of electrical insulation systems is critical to the continuity of energy transmission and distribution systems. Structural defects that occur in polymer-based insulating materials can affect the distribution of electric fields, leading to partial discharges and subsequently serious failures such as breakdowns. In this study, the effects of wormhole structures with different diameters in cross-linked polyethylene (XLPE) insulators on electric field distribution under alternating current (AC), direct current (DC), and composite voltage (AC+DC) components were numerically investigated using COMSOL Multiphysics software. In the system modeled under a needle-plane electrode configuration, significant increases in both volumetric and surface electric field intensities were observed as the diameter of the wormhole increased. Among all cases, composite voltage conditions resulted in the highest field concentrations, indicating increased electrical stress on the insulation. Additionally, higher field intensities were observed under negative polarity than under positive polarity in all cases. The findings highlight the importance of considering wormhole-type defects in the design of insulating systems and analyzing the electrical stress caused by composite voltage conditions.
Ethical Statement
Ethics committee approval was not required for this study because of there was no study on animals or humans.
References
-
Adhikari P, Ghassemi M. 2024. Navigating strategies to mitigate insulation issues within high power density (U)WBG power module packages: A comprehensive review emphasizing alternative encapsulation materials. IEEE Transact Industry Applicat, 2024: 1–22. https://doi.org/10.1109/tia.2024.3520096
-
Annadi RR, Patsa CS. 2020. Estimation of switching surge flashover rate of 1200-kV UHVAC transmission line considering switching overvoltage waveshape. Electr Eng, 102(2): 953–966. https://doi.org/10.1007/s00202-020-00918-7
-
Beroual A, Dang V-H, Perrier C. 2013. Investigation on creeping discharges propagating over pressboard immersed in mineral and vegetable oils under AC, DC and lightning impulse voltages. IEEE Trans Dielectr Electr Insul, 20(5): 1-6.
-
Borghei M, Ghassemi M. 2022. Separation and classification of corona discharges under low pressures based on deep learning method. IEEE Trans Dielectr Electr Insul, 29(1): 319–326. https://doi.org/10.1109/TDEI.2022.3146608
-
Chen Q, Wu Z, Liu F, Yun F, Liu D, Fan J, … Gao C. 2022. The discharge mode of SF6N2Gas mixture in extremely inhomogeneous electric field under power frequency voltage. Conference on Electrical Insulation and Dielectric Phenomena, CEIDP, 13-16 November, pp: 560–563. Institute of Electrical and Electronics Engineers Inc. https://doi.org/10.1109/CEIDP55452.2022.9985344
-
Chen S, Li K, Wang F, Sun Q, Zhong L. 2019. Effect of humidity and air pressure on the discharge modes transition characteristics of negative DC corona. IET Sci Meas Technol, 13(8): 1212–1218. https://doi.org/10.1049/iet-smt.2019.0032
-
Dedeoglu S, Merev A. 2023. Realization of the reference composite voltage waveforms for lightning impulse (LI) voltages superimposed over DC and AC signals. Mapan J Metrol Soc India, 38(3): 597–606. https://doi.org/10.1007/s12647-023-00634-0
-
Dissado LA, Fothergill JC. 1992. Electrical degradation and breakdown in polymers (1st ed.). Institution of Engineering and Technology. London, UK, pp: 54-98.
-
Dong W, Wang X, Tian B, Liu Y, Jiang Z, Li Z, Zhou W. 2019. Use of grafted voltage stabilizer to enhance dielectric strength of cross-linked polyethylene. Polymers, 11(1): 1-6. https://doi.org/10.3390/POLYM11010176
-
Dordizadeh P, Adamiak K, Castle GSP. 2017. Experimental study of the characteristics of Trichel pulses in the needle-plane negative corona discharge in atmospheric air. J Electrostat, 88: 49–54. https://doi.org/10.1016/j.elstat.2016.12.013
-
Fidan M, Ismailoglu H. 2017. Harmonik kaynaklı gerilim bozulmalarının elektriksel kısmi boşalmalar üzerindeki etkilerinin incelenmesi. J Fac Eng Archit Gazi Univ, 32(3): 929–939. https://doi.org/10.17341/gazimmfd.337646
-
Freitas-Gutierres LF, Maresch K, Morais AM, Nunes MVA, Correa CH, Martins EF, … Oliveira AL. 2024. Framework for decision-making in preventive maintenance: Electric field analysis and partial discharge diagnosis of high-voltage insulators. Electr Power Syst Res, 233: 1-6. https://doi.org/10.1016/j.epsr.2024.110447
-
Ghassemi M. 2018. PD measurements, failure analysis, and control in high‐power IGBT modules. High Volt, 3(3): 170–178. https://doi.org/10.1049/hve.2017.0186
-
Gong M, Lu M, Liu H, Jiang H, Sun QF, Xie XC. 2020. Transport study of the wormhole effect in three-dimensional topological insulators. Phys Rev B, 102(16): 1-6. https://doi.org/10.1103/PhysRevB.102.165425
-
Hamidieh M, Ghassemi M. 2024. Conic cross-sectional electrodes and their influence on negative corona discharge and trichel pulse characteristics. IEEE Trans Dielectr Electr Insul, 31(4): 2064–2073. https://doi.org/10.1109/TDEI.2024.3385751
-
Hu K, Li G, Gu Z, Zhang F, Wei Y, Lei Q. 2023. Analysis of influence factors on ac breakdown characteristics of rod-barrier gap and electric field simulation. J Electr Eng Technol, 18(3): 2189–2197. https://doi.org/10.1007/s42835-022-01259-0
-
IEC 60060-1:2010. High-voltage test techniques - Part 1: General definitions and test requirements. 2010: 68.
-
Ispirli MM, Kalenderli Ö, Seifert F, Rock M, Oral B. 2022b. Investigation of impact of DC component on breakdown characteristics for different electric fields under composite AC and DC voltage. High Volt, 7(2): 279–287. https://doi.org/10.1049/hve2.12185
-
Ispirli MM, Oral B, Kalenderli Ö. 2022a. Electric field analysis of 66 kV and 110 kV SiR insulators under combined AC–DC voltages. Energy Rep, 8: 361–368. https://doi.org/10.1016/j.egyr.2021.11.149
-
Kadim EJ, Noorden ZA, Adzis Z, Azis N. 2021. Nanoparticles application in high voltage insulation systems. IEEE Trans Dielectr Electr Insul, 28(4): 1380–1399. https://doi.org/10.1109/TDEI.2021.009531
-
Kavanagh DF, Gyftakis KN, Mcculloch MD. 2020. Thermal degradation phenomena of polymer film on magnet wire for electromagnetic coils. IEEE Trans Ind Appl, 57(1): 458–467. https://doi.org/10.1109/TIA.2020.3040201
-
Küchler A. 2017. High voltage engineering. Springer eBooks, London, UK, pp: 168. https://doi.org/10.1007/978-3-642-11993-4
-
Lan G, Bo L, Huanchao C, Jinzhong Li. 2012. Breakdown characteristics of typical model in transformer oil under AC and DC mixed voltage. 2012 October 14–17, 2012 Annual Report Conference on Electrical Insulation and Dielectric Phenomena. IEEE, Ottawa, Canada, pp: 68.
-
Li Y, Zhang Q, Zhao Y, Wang T, Liu G, Wang K. 2017. The influence of temperature on Partial Discharges and wormhole effect of oil-paper insulation under DC voltage. 2017 June 11–14 IEEE Electrical Insulation Conference (EIC). IEEE, Montreal, Canada.
-
Li Y, Zhou K, Zhu GY, Zhang QG. 2019. Effect of DC discharges in mineral oil on degradation characteristics of oil-impregnated pressboard. IEEE Trans Dielectr Electr Insul, 26(5): 1701–1708. https://doi.org/10.1109/TDEI.2019.008256
-
Li Z, He D, Ren F, Li S, Wu H, Sun Y, … Li Q. 2025. Effect of temperature on the internal electric field distribution and discharge mechanism of converter transformer under AC–DC composite voltage. IEEE Trans Dielectr Electr Insul, 32(2): 1084–1093. https://doi.org/10.1109/TDEI.2024.3435815
-
Liang H, Du B, Li J. 2020. Non-Intrusive measurement of transient electric field distribution under AC and impulse voltages. IEEE Sens J, 20(18): 10898–10902. https://doi.org/10.1109/JSEN.2020.2994246
-
Lin L, Meng X, Mei H, Wang L. 2024. Influence of AC and DC composite voltage on positive streamer discharge. IEEE Trans Dielectr Electr Insul, 31(2): 779–785. https://doi.org/10.1109/TDEI.2023.3325421
-
Liu L, Zhang Z, Peng Z, Ouyang J. 2013. Comparison of point-to-plane corona in different gases. J Phys Conf Ser, 418(1): 1-6. Institute of Physics Publishing. https://doi.org/10.1088/1742-6596/418/1/012092
-
Muppala P, Reddy CC. 2021. Electric field and DC breakdown voltage of multi-layer dielectrics in parallel-plane geometry. IEEE Trans Dielectr Electr Insul, 28(1): 257–265. https://doi.org/10.1109/TDEI.2020.008830
-
Negari S, Moghadam DE. 2024. A novel approach towards parametric assessment of reliability and resilience of high voltage mica-based insulation systems by statistical analysis of experimental failure data. High Volt, 9(2): 495–507. https://doi.org/10.1049/hve2.12431
-
Özkaya M. 2008. Yüksek gerilim tekniği. Birsen Yayınevi, Cilt I, İstanbul, Türkiye, ss: 68.
-
Park C, Lee K, Kim K, Lim H, Park Y. 2024. Evaluation of Time-Based arc flash detection with non-contact UV sensor. J Electr Eng Technol, 19(3): 1983–1992. https://doi.org/10.1007/s42835-023-01555-3
-
Qiu Z, Ruan J, Huang D, Pu Z, Shu S. 2015. A prediction method for breakdown voltage of typical air gaps based on electric field features and support vector machine. IEEE Trans Dielectr Electr Insul, 22(4): 2125–2135. https://doi.org/10.1109/TDEI.2015.004887
-
Reddy BST, Wani SA, Amizhtan SK, Naresh C, Sarathi R. 2023. Understanding the surface discharge activity with nano oil-pressboard insulation under AC and lightning impulse voltages. IEEE Trans Dielectr Electr Insul, 31(2): 889–896. https://doi.org/10.1109/TDEI.2023.3334245
-
Roggendorf C, Schnettler A. 2012. Accelerated hydrothermal aging of epoxy resin based syntactic foams with polymeric microspheres. IEEE Trans Dielectr Electr Insul, 19(3): 973–980. https://doi.org/10.1109/TDEI.2012.6215102
-
Rosenberg G, Guo HM, Franz M. 2010. Wormhole effect in a strong topological insulator. Phys Rev B, 82(4): 1-6. https://doi.org/10.1103/PhysRevB.82.041104
-
Rubinetti D, Iranshahi K, Onwude DI, Nicolaï BM, Xie L, Defraeye T. 2024. Energy-saving discharge needle shape for electrohydrodynamic airflow generation. J Electrostat, 127: 1-6. https://doi.org/10.1016/j.elstat.2023.103876
-
Saini S, Prasad SD. 2024. Quasi-static ac surface charging of polymeric insulators at low pressure. IEEE Trans Ind Appl, 60(4): 5663–5670. https://doi.org/10.1109/TIA.2024.3397773
-
Stone G, Boulter EA, Culbert I, Dhirani H. 2014. Electrical insulation for rotating machines. Design, Evaluation, Aging, Testing, and Repair, London, UK, pp:59-67.
-
Tian H, Liu L, Guo Z, Wang H, Shi R, Peng Z. 2017. Research on electrical field distribution of tri-post insulator and distortion effect by defects. 2017 IEEE Conference on Electrical Insulation and Dielectric Phenomenon (CEIDP). IEEE, 22-25 October, Fort Worth, Texas, USA, pp: 82.
-
Timoshkin IV, Given MJ, Macgregor SJ, Wilson MP, Lehr JM. 2009. Pre-breakdown currents in insulating liquids stressed with non-uniform DC electric field. 2009 June 12–14 IEEE Pulsed Power Conference, Washington DC, USA, pp: 63.
-
Tunç E, Fidan M. 2023. Residual voltage tests of 4.5 kV metal oxide surge arrester. 14th International Conference on Electrical and Electronics Engineering, ELECO 2023 - Proceedings. November 30-December 2, Bursa, Türkiye, pp: 18. https://doi.org/10.1109/ELECO60389.2023.10415938
-
Wu Z, Xu H, Zhou J, Chen Y, Zhang Z, Zhang Q. 2024. Accumulative effect of bipolar oscillation impulse voltage on interturn insulation of transformer winding. IEEE Trans Dielectr Electr Insul, 32(2): 1-6. https://doi.org/10.1109/TDEI.2024.3446768
-
Yang Y, Gao K, Bi J, Ding L, Yuan S, Wang G. 2022. Influence of micro-water on AC breakdown characteristics of C4F7N/CO2 gas mixture under non-uniform electric field. High Volt, 7(6): 1059–1068. https://doi.org/10.1049/hve2.12215
-
Zhang B, Ghassemi M, Zhang Y. 2021. Insulation materials and systems for power electronics modules: A review identifying challenges and future research needs. IEEE Trans Dielectr Electr Insul, 28(1): 290–302. https://doi.org/10.1109/TDEI.2020.009041
-
Zhao L, Su J, Zhang X, Pan Y, Wang L, Fang J, … Cheng J. 2013. An experimental and theoretical investigation into the “wormhole” effect. J Appl Phys, 114(6): 1-6. https://doi.org/10.1063/1.
-
Zhao L. 2022. A unified formula for five basic forms of discharge in an electric field under short pulses. IEEE Trans Plasma Sci, 50(10): 3400–3411. https://doi.org/10.1109/TPS.2022.3169602
-
Zhao T, Liu Y, Liu Y, Yang C, Zheng Y, Zhu W, Gu Z. 2024. Bubble motion characteristics in the transformer oil gap at the top of HV Winding. IEEE Transact Dielectrics Electrical Insulat, 1: 3361848. https://doi.org/10.1109/tdei.2024.3361848
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