# Tracking/Erosion Resistance Analysis of Nano-Al(OH)3 Filled Silicone Rubber Insulating Materials for High Voltage DC Applications

• Kannan, P. ;
• Sivakumar, M. ;
• Mekala, K. ;
• Chandrasekar, S.
• Accepted : 2014.09.16
• Published : 2015.01.01
• 88 17

#### Abstract

HVDC technology has become popular as an economic mode of bulk power transmission over very long distances. Polymeric insulators in HVDC power transmission lines are affected by surface tracking and erosion problems due to contamination deposit, which pose a greater challenge in maintaining the reliability of the HVDC system. In addition, polymeric insulators are also naturally affected by aging due to various environmental stresses, which in turn accelerates the surface tracking and erosion problems. Research works towards the improvement of tracking and erosion resistance of polymeric insulators by adding nano-sized fillers in the base material are being carried out worldwide. However, surface tracking and erosion performance of nano-filled aged polymeric insulators for HVDC applications are not well reported. Hence, in the present work, tracking and erosion resistance of the nano $Al(OH)_3$ filled silicone rubber insulation material has been evaluated under DC voltages at different filler concentrations and aged conditions, as per IEC 60587 test procedures. Leakage current and contact angle measurements were carried out to understand the surface hydrophobicity. Moving average technique was used to analyze the trend followed by leakage current. Water aged specimen shows less tracking resistance when compared with thermal aged specimen. It is observed that nano-filler concentration of 5% is even sufficient to get better tracking/erosion resistance under DC voltages.

#### Keywords

Silicone rubber;Tracking resistance;Leakage current;Nano filler;Hydrophobicity

#### References

1. R. Sarathi, S. Chandrasekar and N. Yoshimura, “Investigation of Tracking Phenomena in Outdoor Polymeric Insulation Material Under DC Voltages Using Wavelets”, IEEE Trans. on Power Delivery, vol. 21, no. 1, pp. 515-517, Jan 2006.
2. R.J. Chang and L. Mazeika, “Analysis of electrical activity associated with inclined plane tracking and erosion of insulating materials,” IEEE Trans. Dielectr. Electr. Insul., vol. 7, no. 3, pp. 394-400, Jun. 2000. https://doi.org/10.1109/94.848923
3. A. H. El-Hag, S. H. Jayaram, and E. A. Cherney, “Fundamental and low frequency harmonic components of leakage current as a diagnostic tool to study aging of RTV and HTV silicone rubber in salt fog,” IEEE Trans. Dielectr. Electr. Insul., vol. 10, no. 1, pp. 128-136, Jan. 2003. https://doi.org/10.1109/TDEI.2003.1176575
4. S. Chandrasekar, C. Kalaivanan, Andrea Cavallini and Gian Carlo Montanari, “Investigations on Leakage Current and Phase Angle Characteristics of Porcelain and Polymeric Insulator under Contaminated Conditions”, IEEE Trans. Dielectr. Electr. Insul., vol. 16, no. 2, pp. 574-583, Apr. 2009. https://doi.org/10.1109/TDEI.2009.4815193
5. Joseph Vimal Vas, B. Venkatesulu and M. Joy Thomas, “Tracking and Erosion of Silicone Rubber Nanocomposites under DC Voltages of both Polarities”, IEEE Trans. Dielectr. Electr. Insul., vol. 19, no. 1, pp. 91-98, Feb 2012. https://doi.org/10.1109/TDEI.2012.6148506
6. S.M. Rowland, G.P. Bruce, Yuting Liu, A. Krivda and L.E. Schmidt, “Use of Image Analysis in DC Inclined Plane Tracking Tests of Nano and Micro Composites”, IEEE Trans. Dielectr. Electr. Insul., vol. 18, no. 2, pp. 365-374, April 2011. https://doi.org/10.1109/TDEI.2011.5739439
7. IEC 60587, Testing method for evaluating the resistance of tracking and erosion of electrical insulating materials used under severe ambient conditions, 1984.
8. S.H. Kim, E.A. Cherney and R. Hackam, “Hydrophobic behavior of insulators coated with RTV silicone rubber,” IEEE Trans. Electr. Insul., vol. 27, no. 3, pp. 610-622, Mar. 1992. https://doi.org/10.1109/14.142726
9. S. Chandrasekar, R. Sarathi and M.G. Danikas, “Analysis of surface degradation of silicone rubber insulation due to tracking under different voltage profiles”, Int. Journal of Electrical Engineering, Springer, May 2006.
10. A.H. El-Hag, L.C. Simon, S.H. Jayaram and E.A. Cherney, “Erosion resistance of nano filled silicone rubber”, IEEE Trans. Dielectr. Electr. Insul., vol. 13, no. 1, pp. 122-128, February 2006. https://doi.org/10.1109/TDEI.2006.1593410
11. T. Tokoro and R. Hackam, “Loss and recovery of hydrophobicity and surface energy of HTV silicone rubber,” IEEE Trans. Dielectr. Electr. Insul., vol. 8, no. 6, pp. 1088-1097, Dec. 2001. https://doi.org/10.1109/94.971469
12. N. Loganathan and S. Chandrasekar, “Analysis of Surface Tracking of Micro and Nano Size Alumina Filled Silicone Rubber for High Voltage AC Transmission”, Journal of Electrical Engineering and Technology, vol. 8, no. 2, pp. 345-353, 2013. https://doi.org/10.5370/JEET.2013.8.2.345
13. L.H. Meyer, E.A. Cherney and S.H.Jayaram, “The Role of Inorganic Fillers in Silicone Rubber for Outdoor Insulation — Alumina Tri-Hydrate or Silica”, IEEE Electrical Insulation Magazine, vol. 20, no. 4, pp. 13-21, July/August 2004.
14. C.Pugazhendhi Sugumaran, “Experimental Investigation on Dielectric and Thermal Characteristics of Nanosized Alumina Filler Added Polyimide Enamel,” Journal of Electrical Engineering and Technology, vol. 9, no. 3, pp.978-983, May 2014. https://doi.org/10.5370/JEET.2014.9.3.978
15. S. Kumagai and N. Yoshimura, “Tracking and erosion of HTV silicone rubber and suppression mechanism of ATH,” IEEE Trans. Dielectr. Electr. Insul., vol. 8, no. 2, pp. 203-211, Apr. 2001. https://doi.org/10.1109/94.919930
16. R. Sarathi, S. Chandrasekar and N. Yoshimura, “Investigations into the Surface Condition of the Silicone Rubber Insulation Material using Multiresolution Signal Decomposition”, IEEE Trans. on Power Delivery, vol. 21, no. 1, pp. 243-252, Jan 2006.
17. Suwarno, “ Leakage Current Waveforms of Outdoor Polymeric Insulators and Possibility of Application for Diagnostics of Insulator Conditions”, Journal of Electrical Engineering & Technology, vol. 1, no. 1, pp. 114-119, 2006. https://doi.org/10.5370/JEET.2006.1.1.114
18. R.Sarathi and S.Chandrasekar, “Diagnostic study of the surface condition of the insulation structure using wavelet transforms and neural networks”, Electric Power Systems Research, Elsevier, vol. 68, no. 2, pp. 137-147, Feb 2004. https://doi.org/10.1016/S0378-7796(03)00155-X
19. L.H. Meyer, “Tracking and Erosion Resistance of RTV Silicone Rubber: Effect of Filler Particle Size and Loading”, in Proc. IEEUPES Transmission & Distribution Conference & Exposition: Latin America, pp. 453-456, 2004.
20. R.S. Gorur, E.A. Cherney and J.T. Burnham, Outdoor Insulators, Ravi S. Gorur Inc Phoenix, Arizona 85044, USA, 1999.

#### Cited by

1. A review of thermoplastic elastomeric nanocomposites for high voltage insulation applications vol.58, pp.S1, 2018, https://doi.org/10.1002/pen.24822