Mehmet Murat İSPİRLİ, Aysel YILMAZ ERSOY

An investigation on characteristics of tracking failure in epoxy resin with harmonic and fractal dimension analysis

Epoxy resins have excellent mechanical and electrical properties; thus, they are commonly preferred in the electrical{electronic sector as insulation materials. These insulation materials experience degradation such as breakdown, tracking, or treeing. Therefore, safety and reliability tests of insulation materials have great importance in estimating the performance of insulation. These tests must be carried out to decrease the risk of electrical insulation fault. In this study, the relationship between tracking failures and the data obtained during experiments was evaluated. Tracking failure performance of epoxy resin was investigated using the IEC 60112 test standard, which is known as the comparative tracking index test. Leakage current data, collected from the experimental setup recorded from a ground electrode, were decomposed by using the Fourier transform method. The 3rd, 5th, and 7th harmonic distortion components of the leakage current data were calculated and their relationship with the number of drops falling on the sample was interpreted. Then the harmonic distortion components relationship was explained under dirty and clean surface conditions. We explained the tracking pattern formed on the surfaces of the samples after completion of the experiments was decomposed using image processing techniques. The capacity, information, and correlation dimensions of the resulting tracking patterns were calculated using fractal dimension analysis. Shapes in the same terms were examined using fractal dimension analysis.

PDF

___

[1] Du B, Gao Y, Liu Y. Effects of gamma-ray irradiation on tracking failure of polymer insulating materials. In: Tsvetkov P, editor. Nuclear Power: Operation, Safety and Environment. Rijeka, Croatia: InTech, 2011. pp. 341- 368.
[2] Yoshimura N, Kumagai S, Du B. Research in Japan on the tracking phenomenon of electrical insulating materials. IEEE Electr Insul M 1997; 5: 8-19.
[3] Ugur M. Modelling and analysis of surface tracking phenomena of solid insulating materials. PhD, University of Manchester, Manchester, UK, 1997.
[4] Du B, Liu HJ. The application of recurrence plot in DC tracking test of gamma-ray irradiated polycarbonate. IEEE T Dielect El In 2009; 16: 17-23.
[5] Chandrasekar S. Investigations on tracking and erosion resistance of nano silicone composite for high voltage outdoor insulation. J Energ Power Eng 2010; 4: 32-40.
[6] Mandelbrot BB. Fractals: Form, Chance and Dimension. San Francisco, CA, USA: Freeman, 1977.
[7] Du B, Zhu XH, Gu L, Liu HJ. Effect of surface smoothness on tracking mechanism in XLPE-Si-rubber interfaces. IEEE T Dielect El In 2011; 18: 176-181.
[8] Kuntman A, Ugur M, Merev A. A study on the investigation of surface tracking in polyester insulators. In: EMO 1999 International Conference on Electrical and Electronics Engineering; 1{5 December 1999; Bursa, Turkey. Ankara, Turkey: EMO. pp. 84-88.
[9] Liu Y, Zhang D, Xu H, Ale-Emran SM, Du B. Characteristic analysis of surface damage and bulk micro-cracks of SiR/SiO 2 nanocomposites caused by surface arc discharges. IEEE T Dielect El In 2016; 23: 2102-2109.
[10] Mitchell GR. Present status of ASTM tracking test methods. J Test Eval 1974; 2: 23-31.
[11] ASTM International. D5288-14. Standard Test Method for Determining Tracking Index of Electrical Insulating Materials Using Various Electrode Materials (Excluding Platinum). West Conshohocken, PA, USA: ASTM Inter- national, 2014.
[12] IEC. Publication 60112. Method for the Determination of the Proof and the Comparative Tracking Indices of Solid Insulating Materials. 4th ed. Geneva, Switzerland: IEC, 2009.
[13] IEC. Publication 112. Recommended Method for Determining the Comparative Tracking Index of Solid Insulating Materials under Moist Conditions. 2nd ed. Geneva, Switzerland: IEC, 1971.
[14] IEC. Publication 112. Method for Determining the Comparative and the Proof Tracking Indices of Solid Insulting Material under Moist Conditions. 3rd ed. Geneva, Switzerland: IEC, 1979.
[15] ASTM International. D3638-12. Standard Test Method for Comparative Tracking Index of Electrical Insulating Materials. West Conshohocken, PA, USA: ASTM International, 2012.
[16] Esen V, Oral B, Akinci T. The determination of short circuits and grounding faults in electric power systems using time-frequency analysis. J Energy South Afr 2015; 26: 123-133.
[17] Mandelbrot BB. On the geometry of homogeneous turbulence, with stress on the fractal dimension of the iso-surfaces of scalars. J Fluid Mech 1975; 72: 401-416.
[18] Uzunoglu CP, Ugur M, Kuntman A. Simulation of chaotic surface tracking on the polymeric insulators with Brownian motion. _ Istanbul University, Journal of Electrical & Electronics Engineering, 2008; 8: 585-592.
[19] Kebbabi L, Beroual A. Fractal analysis of creeping discharge patterns propagating at solid/liquid interfaces: in uence of the nature and geometry of solid insulators. J Phys D Appl Phys 2005; 39: 177-183.
[20] Du B, Gu L. Effects of interfacial pressure on tracking failure between XLPE and silicon rubber. IEEE T Dielect El In 2010; 17: 1922-1930.
[21] Du B, Zhang MM, Han T, Zhu LW. Effect of pulse frequency on tree characteristics in epoxy resin under low temperature. IEEE T Dielect El In 2016; 23: 104-112.
[22] Ugur M, Varlow BR. Analyzing and modeling the 2D surface tracking patterns of polymeric insulation materials. IEEE T Dielect El In 1998; 5: 824-829.
[23] Rasband SN. Chaotic Dynamics of Nonlinear Systems. Mineola, NY, USA: Dover Publications, 2015.
[24] Moon FC. Chaotic and Fractal Dynamics: An Introduction for Applied Scientists and Engineers. Weinheim, Germany: Wiley, 2004.
[25] IEC. 60243-1:2013. Electric Strength of Insulating Materials { Test Methods - Part 1: Tests at Power Frequencies. 3rd ed. Geneva, Switzerland: IEC, 2013.
[26] Ahmadi-Joneidi I, Majzoobi A, Shayegani-Akmal AA, Mohseni H, Jadidian J. Aging evaluation of silicone rubber insulators using leakage current and ashover voltage analysis. IEEE T Dielect El In 2013; 20: 212-220.
[27] Moon FC. Chaotic Vibrations: An Introduction for Applied Scientists and Engineers. New York, NY, USA: Wiley, 1987.
[28] Grassberger P, Procaccia I. Measuring the strangeness of strange attractors. In: Hunt BR, Li TY, Kennedy JA, Nusse HE, editors. The Theory of Chaotic Attractors. New York, NY, USA: Springer, 2004.