International Journal of Energy Engineering          
International Journal of Energy Engineering(IJEE)
ISSN:2225-6563(Print)
ISSN:2225-6571(Online)
Frequency: Yearly
Editor-in-Chief: Prof. Sri Bandyopadhyay(Australia)
TNB Experiences Using Dielectric Response Technique to Assess Insulation Condition of High Voltage Current Transformers
Full Paper(PDF, 505KB)
Abstract:
Tenaga Nasional Berhad (TNB) has experienced over 40 cases of high voltage Current Transformers (CT) failures since 2001 to 2011. Post failure analysis indicated that these failures are suspected highly due to deterioration and contamination of the main insulation system. To reduce premature failures and improve the reliability of the asset, TNB has embarked on a trial study on the use of dielectric response technique known as Frequency Dielectric Spectroscopy (FDS) to assess the insulation condition of in-service high voltage CTs. Field measurements were conducted on selected 137 units CT of voltage class 132 kV and 275 kV in TNB Transmission system. Analysis guideline and flow-chart was developed based on typical value of measured parameters for accurate assessment. To reduce premature failures on CTs, strategic decisions were made based on measured CT conditions and its assessment results.
Keywords:Current Transformer; Assessment; Dielectric Response Technique; Analysis Guideline
Author: Gobi Kannan Supramaniam1, Aizam Talib2, P. Eng,C.Eng.1
1.Tenaga Nasional Berhad, Transmission Division, Malaysia
2.TNB Research, Kajang, Malaysia
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