The Effect of pH and Temperature in the Propagation of Water Treeing in XLPE Insulated Underground Cable

Main Article Content

Narupon Promvichai
Terapong Boonraksa
Boonruang Marungsri

Abstract

Water treeing has become the major problem in XLPE insulated underground cable caused by the moisture penetration. Despite several studies performed, this problem is still not clear on how the moisture can fast damage the XLPE insulated cable under certain operating conditions. This work has studied the effect of pH and temperature of the ionic solutions to the degradation of the XLPE insulation. The study focused on the XLPE cable used in the 22 kV underground distribution systems in Thailand. The ionic solutions involved a 0.1 mole/L of NaCl and CuSOsolutions for degrading the XLPE cable at ambient and 50 °C in 1000 hours and 4000 hours with the electric stress of 22 kV 50 Hz continuously.  CuSOand NaCl revealed a pH of 4.04 to 3.70 and 6.49 to 6.74 from ambient to 50 °C respectively. The higher strength of acidity resulted by CuSO4 at 50 °C was observed to be more effective in the propagation of water treeing across the XLPE insulation. The propagation of water treeing across the XLPE was strongly dependent on the pH level. Temperature above ambient was concluded to be detrimental for XLPE insulation when a CuSO4 ionic solution exists over a long period due to the significant propagation of water treeing.

Article Details

How to Cite
Promvichai, N., Boonraksa, T., & Marungsri, B. (2018). The Effect of pH and Temperature in the Propagation of Water Treeing in XLPE Insulated Underground Cable. ECTI Transactions on Electrical Engineering, Electronics, and Communications, 16(2), 83–89. https://doi.org/10.37936/ecti-eec.2018162.171337
Section
Electrical Power Systems

References

[1] F. Elfrith, Statistical, Electrical and Mathematical Analysis of Water Treed Cross-Linked Polyethylene Cable Insulation, Doctor Thesis, pp. 1-20, 2015.

[2] R. Arora and W. Mosch, High Voltage and Electrical Insulation Engineering, , Wiley-IEEE Press, pp.319-369, 2011.

[3] A. Jayakrishnana, D. Kavihab, A. Arthi, N. Nagarajana and M. Balachandrana, Simulation of Electric Field Distribution in Nano Dielectrics based on XLPE, Materials Today, Vol.3, No.6, pp.2381-2386, 2016.

[4] F. Mauseth, M. Amundsen, A. Lind and H. Fareno, Water Tree Growth of Wet XLPE Insulated Stressed with DC and High Frequency AC, Electrical Insulation and Dielectric Phenomena(CEIDP), pp.692-695, 2012.

[5] D. Fabiani, A. Cavallini, G.C. Montanari, A. Saccani, M. Toselli and F. Pilati, Hybrid Nanostructured Coating of XLPE Insulation, Electrical Insulation and Dielectric Phenomena(CEIDP), pp.315-318, 2012.

[6] M.G. Danikas and T. Tanaka, Nanocomposites a Review of Electrical Treeing and Breakdown, IEEE Electrical Insulation Magazine, Vol. 25, No. 4, pp.19-25, 2009.

[7] B. Marungsri, A. Rawangpai and N. Chomnawang, Investigation Life Time Model of 22 kV XLPE Cable for Distribution System Applications in Thailand, WSEAS Transactions on Circuits and Systems, Vol. 10, No. 2, pp.185-197, 2011.

[8] D. Assay, M. Kurimoto, F. Komori, T. Katol, T. Funabashi, and Y.Suzuoki, Influence of AC Voltage Prestressing on AC Electrical-tree Inception of Deteriorated LDPE with Dried Watertree, Annual Report Conference on Electrical Insulation and Dielectric Phenomena, pp.385-388, 2014.

[9] S. Evert Frederik, The Behavior of Water Trees in Extruded Cable Insulation, Morphology of Water Trees, pp. 39-42, 1989.

[10] T. Gilbert, and L. Christian, Advances in High-Field Insulating Polymeric Material Over the Past 50 Years, IEEE Electrical Insulation Magazine, Vol. 29, No. 5, pp.26-36, 2013.

[11] D. John, Technical, Scientic, & Material Test Documentation,MELBOURNE, Victoria 3163, Australia, [Online]. available from Internet, http://www.acetechnical.com.au/free-articles.php

[12] M. Karakelle and P. J. Phillips, The Influence of Structure on Water Treeing in Crosslinked Polyethylene: Accelerated Aging Methods, IEEE Trans. Electr. Insul., Vol.24, pp.1083-1092, 1989.

[13] J. Ogiwara, K. Yonaha, H. Uehara and K. Kudo, Temperature Characteristics of Water Tree Propagation in a Wide Temperature Range Using XLPE Sheets,IEEE Conf. Electr. Insul. Dielectr. Phenomena, West Lafayette, Indiana, USA, pp.1-4, 2010.

[14] Bangkok Cable, [Online] Document: http://www.bangkokcable.com/product/backoffice/file_upload/140528_12-20(24)kV_CV_1core.pdf

[15] The Engineering Toolbox, Capacitors, [Online] available from Internet, http://www.engineeringtoolbox.com/capacitors-d_1387.html

[16] Olympus BX51, GRIMUS, [Online]. available from Internet, http://www.grimas.hu/metallografia/ipari-mikroszkopk/normal-femmikroszkopok/olympus-bx51-merallografiai-mikroszkop/

[17] Denition of pH, Chemicool Dictionary,[Online]. available from Internet, https://www.chemicool.com/definition/ph.html