A new approach for determination of moisture in paper insulation of in-situ power transformers by combining polarization-depolarization current and return voltage measurement results
Authors:
- 11 December 2013
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Transactions on Dielectrics and Electrical Insulation
- Vol. 20 (6) , 2325-2334
Abstract
Moisture content in an oil-paper insulation system of power transformer accelerates the aging process of cellulose that degrades insulation properties. As a result, dielectric response measurement data is also affected by moisture present in insulation. In time domain these measurements include Return Voltage Measurement and Polarization-Depolarization Current measurement. In addition it is a known fact that power transformer insulation consists of complex structures which is difficult to model in laboratory. Therefore, results obtained from samples prepared under controlled environment may not be applicable to real life power transformer. The present paper discusses a new approach to combine the results obtained from these two methods namely, Return Voltage Measurement and Polarization-Depolarization Current measurement for several power transformers, to find the relation between oil and paper moisture content that is relevant to insitu power transformers.Keywords
This publication has 10 references indexed in Scilit:
- Experimental investigation of insulation parameters affecting power transformer condition assessment using frequency domain spectroscopyIEEE Transactions on Dielectrics and Electrical Insulation, 2012
- Deriving an Equivalent Circuit of Transformers Insulation for Understanding the Dielectric Response MeasurementsIEEE Transactions on Power Delivery, 2005
- PDC measurement evaluation on oil-pressboard samples2004
- Investigation of polarization and depolarization current measurements for the assessment of oil-paper insulation of aged transformersIEEE Transactions on Dielectrics and Electrical Insulation, 2004
- Dielectric spectroscopy in time and frequency domain for HV power equipment. I. Theoretical considerationsIEEE Electrical Insulation Magazine, 2003
- Practical foundations of the RVM (recovery voltage method for oil/paper insulation diagnosis)2002
- On-site diagnosis of power transformers by means of relaxation current measurements2002
- Modeling the polarization spectrum in composite oil/paper insulation systemsIEEE Transactions on Dielectrics and Electrical Insulation, 1999
- Moisture equilibrium in transformer paper-oil systemsIEEE Electrical Insulation Magazine, 1999
- Electrical and chemical diagnostics of transformers insulation. B. Accelerated aged insulation samplesIEEE Transactions on Power Delivery, 1997