Field Experiences With Measurements of Dielectric Response in Frequency Domain for Power Transformer Diagnostics

Blennow, Jörgen; Ekanayake, Chandima; Walczak, K.; García, Belén; Gubanski, Stanislaw

doi:10.1109/tpwrd.2005.861231

Cited by 97 publications

(42 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the same time, ε 1 is increasing with the increase of the polarization intensity [28]. The complex correlations between polarization intensity and the speed of polarization result in the "deceleration zone" in a certain frequency band, which is determined by the measuring temperature, oil paper constituents, aging time, and moisture content [24,29]. Because the insulation structure of the capacitance core in the oil-paper bushing is relatively simple, the polarization of the oil-paper is weaker than that of the transformer oil-paper.…”

Section: How Aging and Moisture Content Affect Tan δmentioning

confidence: 99%

“…The results show that the higher the initial moisture content, the faster decline in DP of insulating paper in the aging process. This phenomenon can be explained by the hydrolysis of cellulose [24]. In addition, hydrogen bonds between the moisture and the insulation paper can reduce the number of hydrogen bonds between the cellulose chains, thus reducing the stability of the molecular chains and increasing the breaking of cellulose.…”

Section: Polymerization Degree (Dp) Of the Insulating Paper And Insulmentioning

confidence: 99%

See 1 more Smart Citation

Study of the Impact of Initial Moisture Content in Oil Impregnated Insulation Paper on Thermal Aging Rate of Condenser Bushing

et al. 2015

View full text Add to dashboard Cite

This paper studied the impact of moisture on the correlated characteristics of the condenser bushings oil-paper insulation system. The oil-impregnated paper samples underwent accelerated thermal aging at 130˝C after preparation at different initial moisture contents (1%, 3%, 5% and 7%). All the samples were extracted periodically for the measurement of the moisture content, the degree of polymerization (DP) and frequency domain dielectric spectroscopy (FDS). Next, the measurement results of samples were compared to the related research results of transformer oil-paper insulation, offering a theoretical basis of the parameter analysis. The obtained results show that the moisture fluctuation amplitude can reflect the different initial moisture contents of insulating paper and the mass ratio of oil and paper has little impact on the moisture content fluctuation pattern in oil-paper but has a great impact on moisture fluctuation amplitude; reduction of DP presents an accelerating trend with the increase of initial moisture content, and the aging rate of test samples is higher under low moisture content but lower under high moisture content compared to the insulation paper in transformers. Two obvious "deceleration zones" appeared in the dielectric spectrum with the decrease of frequency, and not only does the integral value of dielectric dissipation factor (tan δ) reflect the aging degree, but it reflects the moisture content in solid insulation. These types of research in this paper can be applied to evaluate the condition of humidified insulation and the aging state of solid insulation for condenser bushings.

show abstract

Section: How Aging and Moisture Content Affect Tan δmentioning

confidence: 99%

Section: Polymerization Degree (Dp) Of the Insulating Paper And Insulmentioning

confidence: 99%

Study of the Impact of Initial Moisture Content in Oil Impregnated Insulation Paper on Thermal Aging Rate of Condenser Bushing

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Furthermore, in previous studies it has been identified that measuring capacitance between HV and LV (CHL) is least affected by external factors [14]. However in certain circumstances, such as in an auto transformer, winding configuration does not support CHL measurements.…”

Section: Measurement Configurationmentioning

confidence: 99%

“…The usual measurement time for a cycle of FDS measurement could be up to four times the length of the period of the lowest frequency [13]. Numerous studies performed on field application of FDS measurements have revealed that measurement between HV to LV is least affected by different external factors such as bushing conditions, connection configurations and weather conditions [14]. Modeling the FDS response has also been widely discussed.…”

Section: Introductionmentioning

confidence: 99%

Application of polarization based measurement techniques for diagnosis of field transformers

Ekanayake

Saha

et al. 2010

IEEE PES General Meeting

View full text Add to dashboard Cite

show abstract

“…Blennow [19] studied measurement of moisture content in field transformer based on field experience, and presented that precautions should be taken with the results to minimize effects caused by equipment remaining connected to the transformer as well as by external conditions, while the internal relationship between aging and moisture had not be explored. Belén García and Juan Carlos Burgos' studies [20][21][22] focused on moisture diffusion in oil-paper insulation, and explored the influence of temperature, thickness of cardboard, aging and other factors on moisture diffusion coefficient between oil and paper.…”

Section: Introductionmentioning

confidence: 99%

A New Method for Evaluating Moisture Content and Aging Degree of Transformer Oil-Paper Insulation Based on Frequency Domain Spectroscopy

Xia

Gao

et al. 2017

Energies

View full text Add to dashboard Cite

Abstract:The condition of oil-paper insulation is closely related to the life expectancy of a transformer. The accurate results of oil-paper have not been obtained due to the impact of influencing factors. Therefore, in order to improve the evaluation accuracy of oil-paper insulation, in this paper, oil-paper samples which were prepared with different aging and moisture content were analyzed by frequency domain spectroscopy (FDS). Results show that when the moisture content is less than 2%, the range of 10 1~1 0 3 Hz is mainly affected by moisture and aging has little effect. However, with the increase of moisture content, the effect of aging degree on this band became increasingly prominent. S m , which represents the integral value from 10 −1 to 10 −3 Hz, and S DP , which represents the integral value from 10 1 to 10 3 Hz, were extracted as characteristic parameters of moisture content and aging degree respectively. Compensation factors γ which represents the influence ratio of moisture on S DP and φ which represents the influence ratio of aging on S m were introduced to compensate for the influence of moisture content and aging degree on characteristics respectively. Then, a new method was proposed to evaluate the condition of oil-paper based on compensation factors. Through this method, the influence in characteristics can be eliminated by the obtained actual compensation factors, thus distinguishing the internal influence between moisture content and aging degree on FDS. Finally, this method was verified by field test.

show abstract

Field Experiences With Measurements of Dielectric Response in Frequency Domain for Power Transformer Diagnostics

Cited by 97 publications

References 2 publications

Study of the Impact of Initial Moisture Content in Oil Impregnated Insulation Paper on Thermal Aging Rate of Condenser Bushing

Study of the Impact of Initial Moisture Content in Oil Impregnated Insulation Paper on Thermal Aging Rate of Condenser Bushing

Application of polarization based measurement techniques for diagnosis of field transformers

A New Method for Evaluating Moisture Content and Aging Degree of Transformer Oil-Paper Insulation Based on Frequency Domain Spectroscopy

Contact Info

Product

Resources

About