Effect of long-time electrical and thermal stresses upon the endurance capability of cable insulation material

Tzimas, A.; Rowland, S. M.; Dissado, L.A.; Fu, Mingli; Nilsson, U.H.

doi:10.1109/tdei.2009.5293958

Cited by 56 publications

(16 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Space charge measurement using PEA technique can provide further insight into the distribution of conductivity in the insulation but it can be hard to achieve reliable PEA measurements in cables with thick insulation especially when temperature gradients exist throughout the insulation. Considering the challenges above, since long, researchers have been interesting in testing samples obtained from full-scale cables [4] [10] [11] [12]. In this way, while enjoying the advantage of small scale lab condition tests, one obtains representative data from the actual cable insulation.…”

Section: Introductionmentioning

confidence: 99%

Conductivity measurement of plaque samples obtained from the insulation of high voltage extruded cables

Ghorbani¹,

Farkas²,

Hulden³

2017

NORD-IS

View full text Add to dashboard Cite

Good understanding of insulation conductivity is of great importance in development and design of high voltage DC cables. Conductivity of polymeric insulation materials is a property which is quite sensitive to many parameters such as temperature, electric field, chemical composition, thermal history, morphology, etc. Therefore, due to different process history, the results obtained from pressed plaques are not necessarily representative of the insulation behavior in an extruded cable. A method was developed to obtain samples from HV cable in form of plaques with a thicknesses up to a few millimeters. Plaque samples were extracted from two cables, their conductivity at high field was measured and compared to those obtained from fullscale tests; the results, confirm a very good agreement between the small scale and full-scale measurements; this hints to a promising prospect for such small scale characterization techniques.

show abstract

Section: Introductionmentioning

confidence: 99%

Conductivity measurement of plaque samples obtained from the insulation of high voltage extruded cables

Ghorbani¹,

Farkas²,

Hulden³

2017

NORD-IS

View full text Add to dashboard Cite

show abstract

“…The internal defects of cable joints are the main cause of explosions in cable joints. Explosions of cable joints happen due to internal defects that cause changes in the physical fields of cable joints, including electromagnetic fields [4,5], temperature fields [6,7] and stress fields [8][9][10]. Therefore, in order to protect the cable joints and avoid cable joint accidents, especially explosions, it is important to analyze the electromagnetic-thermal-mechanical characteristics of cable joints under internal defect conditions and find methods to evaluate the internal defects of cable joints [11].…”

Section: Introductionmentioning

confidence: 99%

The Coupling Fields Characteristics of Cable Joints and Application in the Evaluation of Crimping Process Defects

Yang

Cheng³

et al. 2016

Energies

View full text Add to dashboard Cite

Abstract:The internal defects of cable joints always accelerate the deterioration of insulation, until finally accidents can arise due to the explosion of the joints. The formation process of this damage often involves changes in the electromagnetic, temperature and stress distribution of the cable joint, therefore, it is necessary to analyze the electromagnetic-thermal-mechanical distribution of cable joints. Aiming at solving this problem, the paper sets up a 3-D electromagnetic-thermal-mechanical coupling model of cable joints under crimping process defects. Based on the model, the electromagnetic losses distribution, temperature distribution and stress distribution of a cable joint and body are calculated. Then, the coupling fields characteristics in different contact coefficient k, ambient temperature T amb and load current I were analyzed, and according to the thermal-mechanical characteristics of a cable joint under internal defects, the temperature difference ∆T f and stress difference ∆σ f of cable surface are applied to evaluate the internal cable joint defects. Finally, a simplified model of the cable joint is set up to verify the accuracy of the coupling field model proposed in this paper, which indicates that the model can be used to analyze the coupling fields characteristics of cable joints and the method can be applied to evaluate crimping process defects of cable joints.

show abstract

“…Then, the cables mentioned above were aged with different aging durations (shortest being 5,000 h) under mono and hybrid electric and thermal stresses. The dielectric strength and trapped charge tests were conducted after aging [16,17]. The results showed that if only electric aging was considered, the dielectric strength was not obviously changed.…”

Section: Introductionmentioning

confidence: 99%

Investigation on insulation material morphological structure of 110 and 220 kV XLPE retired cables for reusing

Yang

Luo

et al. 2014

IEEE Trans. Dielect. Electr. Insul.

View full text Add to dashboard Cite

Most of the 110 and 220 kV cables are in service till the end of life, but part of them would be out of service by refurbishment. This research is focused on evaluating the cable insulation and determining whether the cable can be reused. All the cables used in this research satisfactorily passed the AC voltage and partial discharge tests. Then the fourier transform infrared spectroscopy, thermogravimetry analysis, differential scanning calorimetry, dynamic mechanical analysis, and tensile machine were used to analyze the insulation morphological structure and performance of 20 retired 110 and 220 kV crosslinked polyethylene cables obtained from the Beijing and Zhuhai districts. The results show that the structure parameters which can represent the physical change and the irreversible chemical change of cables have obvious time dependence characteristic. DSC result shows that crystallinity, melting range, and crystallization rate increase slightly with service years. DMA experiment illustrates that the temperature of mechanical loss peak, T γ , shifts to a higher temperature while the mechanical loss increases slightly and temperature dependency of storage modulus increases with service years. The electrical treeing experiment utilized cable operated for 17 years, which is the longest operation year for the samples. Compared with new cable, the cable operated for 17 years has a slight decrease in tree initiation time and an obvious increase in tree propagation time. These experiment data show that the insulation material morphological structure is mainly stable, and the test results are also a contribution to the lifetime expectancy evaluation of the 110 and 220 kV XLPE cable.

show abstract

Effect of long-time electrical and thermal stresses upon the endurance capability of cable insulation material

Cited by 56 publications

References 28 publications

Conductivity measurement of plaque samples obtained from the insulation of high voltage extruded cables

Conductivity measurement of plaque samples obtained from the insulation of high voltage extruded cables

The Coupling Fields Characteristics of Cable Joints and Application in the Evaluation of Crimping Process Defects

Investigation on insulation material morphological structure of 110 and 220 kV XLPE retired cables for reusing

Contact Info

Product

Resources

About