Moisture and electrical discharges effect on naphthenic mineral oil properties

Toudja, T.; Moulai, H.; Nacer, A.; Beldjilali, A.; Khelfane, I.; Debche, A.

doi:10.1049/iet-smt.2013.0262

Cited by 31 publications

(17 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reduction in water content with the application of discharges is mainly due to the evaporation of water traces that are present in the zone of discharge occurrence. A similar result has been reported in mineral oil submitted to discharges of the same energy level [30].…”

Section: Resultssupporting

confidence: 88%

Influence of thermal ageing and electrical discharges on uninhibited olive oil properties

Reffas

Idir

Ziani

et al. 2016

IET Science, Measurement & Technology

Self Cite

View full text Add to dashboard Cite

International audienceIn recent years, significant attention has been paid to biodegradable vegetable oils as an alternative to mineral insulating oils. This study presents the influence of electrical discharges and thermal stress on the variation of the properties of uninhibited olive oil. This latter constitutes a serious environmentally friendly and renewable substitute for currently used mineral oils. The investigated properties are: dielectric loss factor and permittivity, resistivity, acid number, cinematic viscosity, water content, breakdown voltage, flash point and colour index. To analyse the effect of thermal stress, the uninhibited olive oil was aged in sealed bottles at 110°C for durations up to 716 h. As concerns the electrical stress, series of 200 up to 1600 low energy discharges are applied under 50 Hz alternating divergent electric field. Frequency domain spectroscopy has also been performed in order to assess the oil behaviour in a large frequency range (20 Hz-1 MHz). The real part of the complex dielectric permittivity of oil tends to increase with ageing. The obtained results show an acceptable stability with regard to thermal ageing and even an improvement of the oil key properties when submitted to discharges of controlled low energy level

show abstract

Section: Resultssupporting

confidence: 88%

Influence of thermal ageing and electrical discharges on uninhibited olive oil properties

Reffas

Idir

Ziani

et al. 2016

IET Science, Measurement & Technology

Self Cite

View full text Add to dashboard Cite

show abstract

“…The presence of water content (Eq. (7)) in the transformer oils negatively influences the dielectric characteristics of this insulating liquid and also the insulating solid (paper) [20]. The solubility of water in oil depends essentially on three factors: the temperature, the type of oil (mineral or vegetable), and its condition (new or aged).…”

Section: Methodsmentioning

confidence: 99%

Studies of different types of insulating oils and their mixtures as an alternative to mineral oil for cooling power transformers

Rouabeh

M'barki

Hammami

et al. 2019

Heliyon

View full text Add to dashboard Cite

Because of their availability and low cost, mineral oils have been widely used for a long time in power transformers to allow their insulation and cooling. However, their low fire safety and low biodegradability potential have made it necessary to look for other insulating liquids as an alternative to this mineral oil used in high voltage electrical equipment. This work presents an experimental study to compare between the physicochemical characteristics of mineral oil, olive oil, sunflower oil and different oil mixtures. In order to determine mainly the breakdown voltage and the electrical field intensity of electro-convection, oils insulating should be mixed in precise amounts. All tests have been realized in accordance with the standard test procedures: IEC 60156, IEC 60245 and IEC 61125. The obtained results of testing new as well as aged oil samples concerning the resistivity, the dissipation factor tgδ, the conductivity, the viscosity, the breakdown voltage, the increase of the water content and the flexibility of the oil to the movement in an electrical field, show that a half mixture of naphthenic oil and olive oil could be a potential liquid for the insulation of electrical devices and especially power transformers mounted in areas which have a non-cold climate.

show abstract

“…According to an investigation by Ngai and Roland (), there is a correlation between dielectric loss and the chemical structure of polymers. In a different study, the effect of different types of mineral oils on electrical properties was investigated by Toudja et al (). The authors found that the relative permittivity of a fluid depends on the internal structure of the oil and its impact on polarity.…”

Section: Introductionmentioning

confidence: 99%

“…152 (Zahn et al, ), molecular and supermolecular structures of insulating liquids have been listed as one of the factors that influence the dielectric strength. From these studies, it becomes apparent that indeed molecular structures had an influence on the electrical properties of insulating liquids (Forster et al, ; Ngai and Roland, ; Nitta and Aihara, ; Toudja et al, ; Zahn et al, ).…”

Section: Introductionmentioning

confidence: 99%

Effects of Molecular Structure on the Physical, Chemical, and Electrical Properties of Ester‐Based Transformer Insulating Liquids

Raof

Yunus

Rashid

et al. 2019

J Americ Oil Chem Soc

View full text Add to dashboard Cite

This article presents the experimental studies carried out on the environmental friendly polyol ester insulating liquids to investigate the effect of molecular structure on the physical, chemical, and electrical properties. Six different polyol esters that can be produced from the transesterification of various methyl esters with neopentylglycol/trimethylolpropane alcohols were synthesized and compared with those of refined, bleached, and deodorized palm oil (RBDPO) and mineral transformer oil. The finding suggests that the physical properties like fire point, pour point, and viscosity are very much affected by the molecular weight and molecular composition of the polyol esters. The electrical properties are also highly influenced by the molecular structure-related characteristics, such as the polarity, dipole polarization, carbon chain length, and degree of branching. The results confirm the findings of previous studies that the polyol esters and RBDPO have more polarity and dipole polarization compared to mineral oil. The experimental evidence showed that the newly synthesized insulating liquids have favorable thermal and electrical properties, thus suggesting that the insulating liquids have the potential to replace conventional insulating liquids to provide a more sustainable power system in the future.

show abstract

Moisture and electrical discharges effect on naphthenic mineral oil properties

Cited by 31 publications

References 26 publications

Influence of thermal ageing and electrical discharges on uninhibited olive oil properties

Influence of thermal ageing and electrical discharges on uninhibited olive oil properties

Studies of different types of insulating oils and their mixtures as an alternative to mineral oil for cooling power transformers

Effects of Molecular Structure on the Physical, Chemical, and Electrical Properties of Ester‐Based Transformer Insulating Liquids

Contact Info

Product

Resources

About