Field monitoring of parameters and testing of EP and TR-XLPE distribution cables

Katz, C.; Fryszczyn, B.; Regan, A.; Banker, W.A.; Bernstein, Bruce

doi:10.1109/61.772299

Cited by 11 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The elimination of water trees and the increase of AC breakdown strength lengthen the life of the cable by many years. 4 The combination of silicone rejuvenation and increased lightning protection is highly recommended to lengthen the life of these aged cables and increase their protection against a lightning event. …”

Section: Discussionmentioning

confidence: 99%

“…The data demonstrates that the impulse strength of a water-treed cable can degrade to 60-80% of the impulse strength of new cable for EPR and TR-XLPE insulation. Data in [4] shows approximately a 50% drop of the TR-XLPE cable insulation impulse strength after two years of service aging. Data in [5] presents a continuous reduction of the impulse strength of 35 kV XLPE cable over its service life, and reports the remaining impulse breakdown strength after 7 years of service at 30% of its initial value All the research above demonstrate that the system impulse strength can degrade significantly as the cable ages.…”

Section: Lightning Protection For Aged Cable Systemsmentioning

confidence: 99%

“…Although it is more difficult to estimate the impulse strength of aged systems there has been some work done on this topic. Several reports have indicated that the remaining impulse strength of the cable insulation can drop from 20% to 75% depending on the degree of aging [3,4,5]. A 20% reduction in impulse strength can be typical of cables moderately aged, and a reduction in impulse The calculation examples for protective margins under different protection schemes are given in Figure 2 and 3 with the scenarios of 20% and 40% impulse strength reduction as a result of water treeing, respectively.…”

Section: Lightning Protection For Aged Cable Systemsmentioning

confidence: 99%

See 2 more Smart Citations

Lightning protection for aged cable systems — Problems with water trees

Shu¹,

Stagi²,

Derezes³

et al. 2014

2014 IEEE PES T&D Conference and Exposition

View full text Add to dashboard Cite

The injection of a silicone dielectric fluid in to cables to treat the water trees has been practiced for more than 25 years. Lightning protection combined with silicone fluid injection is a unique way to protect critical aged circuits. These circuits are more susceptible to damage as the water trees decrease the impulse strength of the cable. The review of cable rejuvenation and the factors necessary for protecting aged cables will be discussed.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Lightning Protection For Aged Cable Systemsmentioning

confidence: 99%

Section: Lightning Protection For Aged Cable Systemsmentioning

confidence: 99%

See 1 more Smart Citation

Lightning protection for aged cable systems — Problems with water trees

Shu¹,

Stagi²,

Derezes³

et al. 2014

2014 IEEE PES T&D Conference and Exposition

View full text Add to dashboard Cite

show abstract

“…As pointed out by most of the modern literature on the subject [1][2][3][4][5], practical aids for reliability assessment can be given by the knowledge of the degradation mechanisms, which are responsible for component aging and failure. In the field of electrical insulation [6][7][8][9][10][11][12][13][14], such mechanisms were well established also by virtue of the availability of "accelerated tests" [15][16][17][18]. These aging and life models, when inserted in a probabilistic framework, lead to "physical reliability models".…”

Section: Introductionmentioning

confidence: 99%

Electrical insulation components reliability assessment and practical Bayesian estimation under a Log-Logistic model

Chiodo

Noia

Mottola

2018

IJET

View full text Add to dashboard Cite

This paper deals with the “physical reliability models” assessment and estimation for electrical insulation components. It is well known that the reliability model identification and estimation of most of the modern power system components, such as insulation components, may be better achieved, instead that using limited lifetime data, by the knowledge of the degradation mechanisms. Such mechanisms, which are responsible for component aging and failure, are indeed well established in the field of electrical insulation: this is also the case of the so called “Stress-Strength” models. In particular, the “Log-logistic” model, deduced by a suitable Weibull stress-strength probabilistic model, has found valid applications to the reliability assessment of the insulation components. In the framework of the estimation of such reliability model, a new Bayesian approach, based upon the “Odds Ratio” of the Log-logistic model is developed in this paper, based upon the properties that such information, being proportional to the reliability function, is available to the engineer on the basis of past data; moreover, being proportional to the Weibull scale parameter, allows to exploit known features of its conjugate prior Inverse Gamma distribution. Numerical examples and the results of extensive Monte Carlo simulations demonstrate the feasibility and efficiency of the proposed procedure.

show abstract

“…the following by Tp; (14) which are, of course, rv whose pdf depends on the assumed pdf for Z. In particular, in the numerical application, we have quantities:…”

Section: Outline Of the Proposed Bayesianmentioning

confidence: 99%

Bayes inference for reliability of uv insulation systems in the presence of switching voltage surges using a weibull stress-strength model

Chiodo

Fabiani

Mazzanti

2003 IEEE Bologna Power Tech Conference Proceedings,

View full text Add to dashboard Cite

This paper shows a Bayesian approach to evaluate the effect of switching overvoltages on HV insulation reliability. Indeed, HV insulation is often designed to withstand rated temperature and nominal (AC or DC) voltage but not voltage surges, whose amplitude can largely exceed rated voltage even in the case of switching overvoltages. Since both voltage surges and insulation electric strength (affected by aging) have stochastic nature, reliability evaluation involves the use of the relevant probability distributions, whose parameters a r e generally known with large uncertainty. Thus, the methodology for reliability assessment here presented, based on Bayesian estimation, is a useful tool in the case of HV insulation subjected to switching voltage surges. Under proper assumptions, among which a particular Weibull stress-strength model -leading to a Loglogistic distribution for lifetime -the proposed method enables the analytical determination of prior and posterior distributions of reliability and other related parameters, such as given percentiles of service life, and their Bayes point and interval estimates. The analytical feasibility and simplicity of the procedure a r e illustrated in the paper by means of a numerical application, and the efficiency of estimates is shown through extensive Monte Carlo simulations. The method is applied to HVAC cable insulation.

show abstract

Field monitoring of parameters and testing of EP and TR-XLPE distribution cables

Cited by 11 publications

References 8 publications

Lightning protection for aged cable systems — Problems with water trees

Lightning protection for aged cable systems — Problems with water trees

Electrical insulation components reliability assessment and practical Bayesian estimation under a Log-Logistic model

Bayes inference for reliability of uv insulation systems in the presence of switching voltage surges using a weibull stress-strength model

Contact Info

Product

Resources

About