TY - JOUR

T1 - On the frequency domain dielectric response of oil-paper insulation at low temperatures

AU - Fofana, Issouf

AU - Hemmatjou, Hossein

AU - Meghnefi, Fethi

AU - Farzaneh, Masoud

AU - Setayeshmehr, Alireza

AU - Borsi, Hossein

AU - Gockenbach, Ernst

N1 - Funding information: This work was carried out within the framework of the Canada Research Chair, ISOLIME and the International Research Center, CENGIVRE at the University of Quebec in Chicoutimi. The authors would like to thank J. Cross and Weidmann of Electrical Technology Inc. (United States) for their support in materials as well as all the sponsors/collaborators of the project. electrical engineering degree from the École Polytechnique of Iran in 1973. He received successively a doctoral degree in engineering from Institut nationale polytechnique and Université Paul Sabatier, in France, and a Doctorat d'État from the latter university. From 1980 to 1982, he was Associate Professor at Université des Sciences et de la Technologie d'Oran, Algeria. He joined Université du Québec à Chicoutimi (UQAC) in 1982 as a guest professor. Following this, he became a full professor, as well as founder and Director of the Master's Degree Program in Engineering. He is currently Chairholder of the NSERC/Hydro-Quebec Industrial Chair on Atmospheric Icing (CIGELE), and Chairholder of the Canada Research Chair on Atmospheric Icing Engineering of Power Networks (INGIVRE). He is also founder of the International Research Centre on Atmospheric Icing and Engineering of Power Networks (CENGIVRE) of which he is currently Director. Prof. Farzaneh is author and co-author of more than 800 scientific publications in the domain of high voltage, outdoor insulation and atmospheric icing. He is Fellow of the Institution of Electrical Engineers (IEE), Fellow of the Engineering Institute of Canada (EIC), Charter Member of the International Society of Offshore and Polar Engineers (ISOPE) as well as member of the New York Academy of Sciences and the American Association for the Advancement of Sciences. He is currently Associate Editor of IEEE Transactions on Dielectrics and Electrical Insulation, Chairman of the IEEE DEIS Outdoor Insulation Committee, as well as Chairman or member of several working groups and task forces of IEEE and CIGRÉ dealing with atmospheric icing of HV equipment.

PY - 2010/6

Y1 - 2010/6

N2 - Results of Frequency Domain Spectroscopy measurements are known to be largely influenced by environmental conditions, such as the temperature. Because field measurements, last hours after de-energizing the transformer, the ambient temperature may affect the results. Especially in cold regions of the world, extreme care are required to interpret the results when performing tests at relatively low surrounding temperatures. A better understanding and analysis of the dielectric test results are therefore only possible with a clear understanding of the physical behavior of the insulation system in response to the ambient conditions. In this contribution, the dielectric behavior of a composite oil paper insulation system has been explained from the properties of Debye basic model. A series of experiments have been performed under controlled laboratory conditions with preset moisture content inside the insulation. The equivalent circuit parameters of a laboratory made oil paper condenser bushing model were obtained using a non-linear optimization procedure. Since the dielectric parameters values are geometry dependent, poles, calculated from resistances and capacitances, were used as they are independent of the geometry. It was shown that the poles can be regarded as parameters able to be used for insulation condition assessment.

AB - Results of Frequency Domain Spectroscopy measurements are known to be largely influenced by environmental conditions, such as the temperature. Because field measurements, last hours after de-energizing the transformer, the ambient temperature may affect the results. Especially in cold regions of the world, extreme care are required to interpret the results when performing tests at relatively low surrounding temperatures. A better understanding and analysis of the dielectric test results are therefore only possible with a clear understanding of the physical behavior of the insulation system in response to the ambient conditions. In this contribution, the dielectric behavior of a composite oil paper insulation system has been explained from the properties of Debye basic model. A series of experiments have been performed under controlled laboratory conditions with preset moisture content inside the insulation. The equivalent circuit parameters of a laboratory made oil paper condenser bushing model were obtained using a non-linear optimization procedure. Since the dielectric parameters values are geometry dependent, poles, calculated from resistances and capacitances, were used as they are independent of the geometry. It was shown that the poles can be regarded as parameters able to be used for insulation condition assessment.

KW - Conductivity

KW - Dielectric spectroscopy

KW - Frequency domain

KW - Low temperatures

KW - Moisture content

KW - Oil-paper insulation

KW - Poles

UR - http://www.scopus.com/inward/record.url?scp=77954188676&partnerID=8YFLogxK

U2 - 10.1109/TDEI.2010.5492253

DO - 10.1109/TDEI.2010.5492253

M3 - Article

AN - SCOPUS:77954188676

VL - 17

SP - 799

EP - 807

JO - IEEE Transactions on Dielectrics and Electrical Insulation

JF - IEEE Transactions on Dielectrics and Electrical Insulation

SN - 1070-9878

IS - 3

M1 - 5492253

ER -