Thermal Degradation and Condition Monitoring of Low Voltage Power Cables in Nuclear Power Industry

Mustafa, Ehtasham; Adam, Tamus Zoltan; Afia, Ramy S. A.; Asipuela, Angel

doi:10.1007/978-3-030-17771-3_35

Cited by 17 publications

(7 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to these reactions, materials such as CSPE, which has chlorine and sulfur dioxide attached to the polyethylene backbone, undergo dehydrohalogenation. During dehydrohalogenation, the halogen atom is separated from the polymer chain and the hydrogen, resulting in double bonds in the polymer chain [48,49], resulting in increased conductivity and permittivity [50].…”

Section: Discussionmentioning

confidence: 99%

Comparison of Mechanical and Low-Frequency Dielectric Properties of Thermally and Thermo-Mechanically Aged Low Voltage CSPE/XLPE Nuclear Power Plant Cables

2021

Self Cite

View full text Add to dashboard Cite

During the service period of low-voltage nuclear cables, multiple stresses influence the aging of polymeric materials of cables. Thermal and radiation stresses are considered service aging factors in qualification tests, while the standards usually do not prescribe mechanical stress. CSPE/XLPE insulated nuclear cable samples were exposed to thermal and combined thermo-mechanical aging for more than 1200 h at 120 °C. The real and imaginary parts of permittivity were measured in the 200 μHz to 50 mHz range as dielectric properties. The Shore D hardness of the samples was measured to analyze the mechanical characteristics of the cable. To characterize the dielectric spectrum, derived quantities, namely central real and imaginary permittivities and real and imaginary permittivities’ central frequencies were calculated. The change of dielectric spectra did not show a clear trend with aging, but the imaginary permittivity’s central frequency was higher by 0.5 mHz in the case of thermo-mechanically aged samples. The Shore D hardness was also higher on the thermo-mechanically aged samples. These findings show the combined aging has a higher impact on the insulation properties. Hence, involving the mechanical stress in the aging procedure of cable qualification enables the design of more robust cables in a harsh environment.

show abstract

Section: Discussionmentioning

confidence: 99%

Comparison of Mechanical and Low-Frequency Dielectric Properties of Thermally and Thermo-Mechanically Aged Low Voltage CSPE/XLPE Nuclear Power Plant Cables

2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Like EPR, CSPE under irradiation experiences a series of reactions, i.e., cross-linking, chain scission, and oxidation. Apart from these reactions' chlorine loss, dehydrochlorination, a chain reaction [32][33][34], also occurs during irradiation. In the presence of oxygen, there is the formation of small molecular radicals and macromolecular radicals.…”

Section: Cspe Jacketmentioning

confidence: 99%

Implementation of Non-Destructive Electrical Condition Monitoring Techniques on Low-Voltage Nuclear Cables: I. Irradiation Aging of EPR/CSPE Cables

et al. 2021

Self Cite

View full text Add to dashboard Cite

In a nuclear power plant environment, low-voltage cables experience different stresses during their service life which challenge their integrity. A non-destructive and reliable condition monitoring technique is desired to determine the state of these low-voltage cables during service and for the life extension of nuclear power plants. Hence, in this research work, an EPR/CSPE-based low-voltage cable was exposed to γ-rays for five different absorbed doses. The overall behavior of the cable under stress was characterized by frequency and time domain electrical measurements (capacitance, tan δ, and Extended Voltage Response) and a mechanical measurement (elongation at break). Significant variations in the electrical parameters were observed, as was a decline in the elongation at break values. A strong correlation between the measurement methods was observed, showing the ability of the electrical methods to be adopted as a non-destructive condition monitoring technique.

show abstract

“…The load loss capitalization cost in the examined case is 3533 €/kW and the core loss capitalization is 7066 €/kW. The insulation distances were chosen by the widely used a priori empirical rules [3,23,27,29,30]. These insulation distance selection Fig.…”

Section: Regulation Typementioning

confidence: 99%

Non-linear Impact of the Short Circuit Impedance Selection on the Cost Optimized Power Transformer Design

Orosz

Tamus

2020

Period. Polytech. Elec. Eng. Comp. Sci.

View full text Add to dashboard Cite

Since the electrical machine design is a complex task it can be divided into sub-problems, e.g. preliminary and final design processes and checking of the final design. This paper deals with the preliminary design process, which provides the key-design parameters of the electrical machine. Traditionally, these electrical machine models in preliminary design phase neglect or use oversimplified insulation system models and the tap changing selection is not involved during the calculation of key-design parameters. The aim of this study is to assess the effect of the insulation distance minimization and tap-changing on the key design parameters of a cost-optimized large power transformer. For this purpose, the paper shows some examples, where the cost optimal design — in contrast to the classical insulation design rule — contains larger insulation distances than the possible minimum values. The effect of tap-changing methods are also investigated. These cost optimization made by a verified, metaheuristic method-based transformer optimization algorithm. The results show involving the insulation design and tap-changing selection into the preliminary design process can provide more economical designs.

show abstract

Thermal Degradation and Condition Monitoring of Low Voltage Power Cables in Nuclear Power Industry

Cited by 17 publications

References 11 publications

Comparison of Mechanical and Low-Frequency Dielectric Properties of Thermally and Thermo-Mechanically Aged Low Voltage CSPE/XLPE Nuclear Power Plant Cables

Comparison of Mechanical and Low-Frequency Dielectric Properties of Thermally and Thermo-Mechanically Aged Low Voltage CSPE/XLPE Nuclear Power Plant Cables

Implementation of Non-Destructive Electrical Condition Monitoring Techniques on Low-Voltage Nuclear Cables: I. Irradiation Aging of EPR/CSPE Cables

Non-linear Impact of the Short Circuit Impedance Selection on the Cost Optimized Power Transformer Design

Contact Info

Product

Resources

About