Fundamental research on the application of nano dielectrics to transformers

Liu, Rongsheng; Pettersson, Lars; Auletta, Tommaso; Hjortstam, Olof

doi:10.1109/ceidp.2011.6232685

Cited by 60 publications

(58 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The maximum temperature of the non-modified oil is 40. 5 while only 36 of the 0.1 wt% sample. Taking into consideration of the obtained result in Figure 9, it can be confirmed that the heat generated by the source is conducted and dissipates to the entire oil in a faster way due to the addition of BN nanoparticles.…”

Section: Thermal Conductivitymentioning

confidence: 90%

“…When the concentration of the nanooil is 0.1 wt% the temperature decline to 32. 5 at the end of the cooling process in contrast to 30.5 of the non-modified oil. As temperature difference effectively affects the heat conduction process, it can be concluded that the non-modified oil with higher temperature contributes to the heat dissipation process and leads to faster temperature drop.…”

Section: Thermal Conductivitymentioning

confidence: 98%

“…In recent years, many researchers have been concentrated on preparing nanooil by dispersing nanoparticles into transformer oil and measuring the electrical property [3][4][5]. Sugumaran has pointed the improvement in relative permittivity and breakdown strength of nanooil modified by TiO 2 and ZrO 2 nanoparticles due to the high relative permittivity of the fillers [6].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

High thermal conductivity transformer oil filled with BN nanoparticles

Xiao

2015

IEEE Trans. Dielect. Electr. Insul.

View full text Add to dashboard Cite

Transformer oil is widely used in electric transformers serving the dual functions as insulating medium and cooling material. However, safety and stability of power system is interrupted due to the operation failure of electric transformers in certain case. Therefore efforts should be focused on improving the property of transformer oil for the stable operation of insulating system. The purpose of this paper is to obtain a new type of nanomodified transformer oil with improved dielectric and thermal properties. Boron nitride (BN) nanoparticles with high thermal conductivity were dispersed into transformer oil to form the nanooil. Dielectric and thermal properties of the samples before and after modification were measured. Dielectric property experiments were performed in accordance with IEC standard. Discharge phenomenon in breakdown process was captured by a high speed CCD camera. In order to investigate the effect of BN nanoparticles on thermal property, temperature change and heat distribution of the samples in heat transfer process were measured by an infrared thermal imager and a temperature sensor. It is found that the nanooil has higher dielectric breakdown strength and lower dissipation factor which indicate better dielectric property compared with nonmodified oil. Obtained results show significant improvement in heat transfer process with increasing the concentration of BN nanoparticles. It is proposed that the nanoparticles create an interfacial region which contributes to the enhancement of dielectric strength. For thermal property the ballistic phonon transport of the nanoparticles acts as the key factor in the remarkable improvement. Furthermore, the improved thermal property of the nanooil has an inhibitory effect on the breakdown process according to the bubble theory.

show abstract

Section: Thermal Conductivitymentioning

confidence: 90%

Section: Thermal Conductivitymentioning

confidence: 98%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

High thermal conductivity transformer oil filled with BN nanoparticles

Xiao

2015

IEEE Trans. Dielect. Electr. Insul.

View full text Add to dashboard Cite

show abstract

“…Therefore, it is still the industry preferred choice for transformer insulation/cooling. Yet, the race for higher power densities in transformers has led researchers around the world to experiment with nanofluids, hoping to improve the heat transfer capability of mineral oil, thus achieving more compact and economic units [2].…”

Section: Introductionmentioning

confidence: 99%

“…Their role in heat transfer improvement was established about 15 years ago, [3]. Defying a long-proven evidence, the purer the mineral oil the higher its dielectric withstand capability, it was demonstrated that adding nanoparticles (i.e., something that could be regarded as an impurity) to transformer oil improves breakdown voltage under lightning impulse conditions [2]. This fact has been explained in [4] considering that conductive nanoparticles behave as electron scavengers, i.e., they tend to attract electrons and getting charged.…”

Section: Introductionmentioning

confidence: 99%

Investigations on the effect of nanoparticles in mineral oil

Rajendran

Cavallini

Azcarraga

2014

2014 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP)

View full text Add to dashboard Cite

Power transformers are one of the critical components in power system; traditionally mineral oil is used in transformers for the purpose of dielectrics as well as cooling. In this work, an investigation has been carried out to analyze the performance of Ferrofluids (nano fluids) along with mineral oil for various concentrations. Ferrofluids concentration of 0.1g/liter, 0.2g/liter and 0.5g/liter has been prepared with moisture content less than 5 ppm. Partial Discharge Inception Voltage (PDIV), discharge characteristics of test samples for AC, DC positive and negative voltage is analyzed. Moreover charges produced for each Partial Discharge (PD) have been evaluated. The results illustrate that Ferrofluids with lower concentration shows enhanced PDIV and charge accumulation characteristics than other concentrations as well as mineral oil.I.

show abstract

Retreatment of aged mineral oil using semiconductive nanocomposites for power transformer application

Thirugnanam

Siluvairaj

Rajendran³

2017

Int Trans Electr Energ Syst

View full text Add to dashboard Cite

Summary Power transformer plays a vital role in power system network, and it mainly consists of liquid and solid insulations. In this mineral oil plays a major insulation role and cooling purpose. Moisture and prolonged electric stress leads the way for ageing in transformer insulation. It results in degradation of insulation properties and hindrance in uninterrupted operation. Due to thermal degradation, insulation loosens its dielectric withstand properties. To avoid this, periodic condition monitoring is required to protect the transformer insulation. In this work, an effort has been taken to investigate the aged mineral oil using semiconductive nanocomposites by retreatment technique. The nanocomposites are added with the aged oil in different volume fractions to evaluate the enhancement level of aged oil for reutilization purpose. The critical properties like breakdown voltage, dielectric loss, resistivity, dielectric permittivity, viscosity, flash point, and acidity of the samples before and after treatment are measured according to American Society for Testing and Materials (ASTM) and International Electro‐technical Commission (IEC) standards. It is found that semiconductive nanocomposites improve the critical properties of aged oil and suitable proportion of volume fractions shows impressively enhanced results than base fluid samples. The result paves a new way in economic retreatment of aged oil under environmental friendly nature for reutilization purpose.

show abstract

Fundamental research on the application of nano dielectrics to transformers

Cited by 60 publications

References 2 publications

High thermal conductivity transformer oil filled with BN nanoparticles

High thermal conductivity transformer oil filled with BN nanoparticles

Investigations on the effect of nanoparticles in mineral oil

Retreatment of aged mineral oil using semiconductive nanocomposites for power transformer application

Contact Info

Product

Resources

About