Breakdown Strength Characteristic of RBDPO and Mineral Oil Mixture as an Alternative Insulating Liquid for Transformer

Mineral oil (MO) works as an important electrical insulation and coolant in transformer which is non-biodegradable and nearly running out. Therefore, for sustainable and environmental concern, an alternative biodegradable insulating oil that potential to replace the mineral oil is introduced. In view of that, the breakdown strength characteristic of Refined Bleached Deodorized Palm Oil (RBDPO) and MO mixtures were investigated by varying the mixing percentage of RBDPO from 0% to 100% at 40oC. The results showed that the breakdown strength of the oil mixture abruptly decline to the minimum breakdown voltage of 50 kV at 20% of RBDPO mixture and gradually increased when the ratio of the RBDPO is added. The highest breakdown strength is achieved 87kv at 80% of RBDPO content. The result of kinematic viscosity is also presented.

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Effect of Water on Electrical Properties of Refined, Bleached, and Deodorized Palm Oil (RBDPO) as Electrical Insulating Material

Jurnal Teknologi ◽

10.11113/jt.v64.2108 ◽

2013 ◽

Vol 64 (4) ◽

Cited By ~ 1

Author(s):

Nazera Ismail ◽

Yanuar Z. Arief ◽

Zuraimy Adzis ◽

Shakira A. Azli ◽

Abdul Azim A. Jamil ◽

...

Keyword(s):

Electrical Properties ◽

Breakdown Voltage ◽

Palm Oil ◽

Pour Point ◽

Electrical Breakdown ◽

Dissipation Factor ◽

Mineral Oil ◽

Flash Point ◽

Effect Of Water ◽

Insulating Liquid

This paper describes the properties of refined, bleached, deodorized palm oil (RBDPO) as having the potential to be used as insulating liquid. There are several important properties such as electrical breakdown, dielectric dissipation factor, specific gravity, flash point, viscosity and pour point of RBDPO that was measured and compared to commercial mineral oil which is largely in current use as insulating liquid in power transformers. Experimental results of the electrical properties revealed that the average breakdown voltage of the RBDPO sample, without the addition of water at room temperature, is 13.368 kV. The result also revealed that due to effect of water, the breakdown voltage is lower than that of commercial mineral oil (Hyrax). However, the flash point and the pour point of RBDPO is very high compared to mineral oil thus giving it advantageous possibility to be used safely as insulating liquid. The results showed that RBDPO is greatly influenced by water, causing the breakdown voltage to decrease and the dissipation factor to increase; this is attributable to the high amounts of dissolved water.

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Study of Breakdown Voltage of Vegetables oil with SiO2 Nanoparticle Additive

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v12.i1.pp296-302 ◽

2018 ◽

Vol 12 (1) ◽

pp. 296

Author(s):

Muhammad Bin Yahya ◽

Fatin Amirah Binti Amirrazli

Keyword(s):

Breakdown Voltage ◽

Palm Oil ◽

Coconut Oil ◽

Mineral Oil ◽

Partial Discharges ◽

Transformer Oil ◽

Different Temperatures ◽

The Mean ◽

Insulating Liquid ◽

Positive Results

This paper investigates the suitability of vegetable oils to replace mineral oil based on its AC breakdown voltage, partial discharge and viscosity. The purpose of the study is to analyze the effect of the nanofluids containing SiO2 nanoparticle in vegetables oils; namely, Coconut oil and Palm oil. A nanofluid is a fluid containing nanoparticles. However, the precise effects on the electrical properties is still uncertain. For decades, transformers use petroleum-based mineral oil because of its good dielectric properties and cooling capability. Coconut oil (CO) and Palm oil (PO) are thought to be suitable alternatives to replace mineral oil as transformer oil as they are sustainable and available in plenty as natural resources. It was obtained in this study that the breakdown voltages of these raw oils have fulfilled the standard specifications of good insulating liquid. However, the addition of SiO2 did not improve the AC breakdown voltage and viscosity of coconut oil and palm oil at different temperatures. However, the addition of SiO2 gave positive results in the values of partial discharges in which the presence of the nanoparticles has greatly reduced the mean volume of partial discharges for both coconut oil and palm oil.

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Electrical Breakdown Voltage of Palm Oil and Nano Graphene Filler in Nanofluids Application on Transformer Insulating Oil

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.902.59 ◽

2021 ◽

Vol 902 ◽

pp. 59-63

Author(s):

Kanin Wajanasoonthon ◽

Amnart Suksri

Keyword(s):

Breakdown Voltage ◽

Palm Oil ◽

Electrical Breakdown ◽

High Viscosity ◽

Mineral Oil ◽

Power Transformers ◽

Environment Friendly ◽

Insulating Oil ◽

Graphene Nanoparticles ◽

Nano Graphene

Generally, power transformers have been using mineral oil as a liquid insulator due to its availability and excellent dielectric property. However, petroleum sources are depleting, which implies that mineral oil is going to be limited in availability. So, this research is to investigate on vegetable oil with nanographene filler as a substitution. Vegetable insulating oil is considered as environment-friendly insulating oil due to their superiority of biodegradable, nature-friendly, high fire-point, and good level of breakdown voltage (BV). Nevertheless, vegetable insulating oil have high viscosity, leading to a slow flow rate on the cooling performance of power transformers. To solve this problem, a process of transesterification was used to produce palm oil methyl ester (POME) from a refined bleached deodorized palm olein (RBDPO) to reduce its viscosity. RBDPO and POME were used as two kinds of fluid-based to combine with graphene nanoparticles (GNPs). Electrical breakdown voltage tests were performed by the IEC60156 standard. The results shown that POME have higher BV than RBDPO but adding GNPs may lead to lower BV even with a small amount of concentration. Nevertheless, every nanofluid has a higher BV than 30 kV.

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Investigation on Voltage Breakdown of Natural Ester Oils Based-On Zno Nanofluids

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1119.175 ◽

2015 ◽

Vol 1119 ◽

pp. 175-178 ◽

Cited By ~ 4

Author(s):

Wittawat Saenkhumwong ◽

Amnart Suksri

Keyword(s):

Power System ◽

Breakdown Voltage ◽

Palm Oil ◽

Breakdown Strength ◽

Mineral Oil ◽

Transformer Oil ◽

Slow Process ◽

Zno Nanofluids ◽

Voltage Breakdown ◽

Natural Ester

Transformer is one of the major component, which is the most important device in power system. Their lifetime depends upon liquid insulation that help transfer the heat out of its winding inside of transformer. Transformer oil uses mineral oil that is the most commonly used has very slow process on decomposition and non-biodegrade. This paper presents the investigation on breakdown voltage of two types of natural ester oils, including palm oil and soy bean based-on ZnO nanofluids. Nanofluids that use nanoparticles modified by use of surfactant that are suspended by process of sonication. Different fraction of nanoparticles were investigated from 0.1% - 0.5% by weight. The breakdown voltage were measured according to ASTM D877. The voltage breakdown strength increased significantly when nanoparticles were added in oils. The obtained results will enable transformer industry to develop liquid insulation dielectric for use in transformer in the future.

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Electrophysical properties of mixtures of mineral oil and synthetic ester dielectric liquid

Safety and Reliability of Power Industry ◽

10.24223/1999-5555-2021-14-2-132-141 ◽

2021 ◽

Vol 14 (2) ◽

pp. 132-141

Author(s):

M. N. Lyutikova ◽

S. M. Korobeynikov ◽

A. A. Konovalov

Keyword(s):

Dielectric Loss ◽

Breakdown Voltage ◽

Loss Tangent ◽

Dielectric Loss Tangent ◽

Kinematic Viscosity ◽

Mineral Oil ◽

Flash Point ◽

Power Transformers ◽

Synthetic Ester ◽

Insulating Properties

Power transformers are key equipment in power generation, transmission, and distribution systems. The reliability of power transformers is based on the performance of the insulation system, which includes solid cellulose insulation and a liquid dielectric. Modern power engineering requires liquid insulation to have excellent insulating properties, high fire resistance, and biodegradability. Mineral oil that has been in use for over 100 years does not meet certain requirements. Therefore, various methods of enhancing the insulating properties of the oil are currently being considered, including mixing it with other liquid dielectrics, which have excellent properties. Synthetic and natural esters are considered as alternative fluids.This article discusses the possibility of enhancing the insulating characteristics of mineral oil with a high content of aromatic hydrocarbons (for example, T-750 oil) by mixing it with synthetic ester Midel 7131. Assessment is given of insulating parameters of the resulting mixtures with an ester fraction in mineral oil from 0% to fifty%. The main characteristics of the mixtures are described, such as density, kinematic viscosity, flash point, dielectric loss tangent, relative dielectric permittivity, breakdown voltage, and moisture content. It is shown that with an increase in the proportion of ester, some parameters of the obtained insulating liquid improve (flash point, dielectric constant, breakdown voltage), while values of other parameters (density, kinematic viscosity, dielectric loss tangent) with an ester content of more than 10% in the mixture do not meet the requirements for mineral oils.

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The Impact of TiO2 Nanoparticle Concentration Levels on Impulse Breakdown Performance of Mineral Oil-Based Nanofluids

Nanomaterials ◽

10.3390/nano9040627 ◽

2019 ◽

Vol 9 (4) ◽

pp. 627 ◽

Cited By ~ 6

Author(s):

Ziyi Wang ◽

You Zhou ◽

Wu Lu ◽

Neng Peng ◽

Weijie Chen

Keyword(s):

Tio2 Nanoparticles ◽

Electric Fields ◽

Breakdown Voltage ◽

Concentration Level ◽

Breakdown Strength ◽

Mineral Oil ◽

Interfacial Region ◽

Bulk Oil ◽

Lightning Impulse ◽

The Impact

The insulation of mineral oil-based nanofluids was found to vary with different concentration level of nanoparticles. However, the mechanisms behind this research finding are not well studied. In this paper, mineral oil-based nanofluids were prepared by suspending TiO2 nanoparticles with weight percentages ranging from 0.0057% to 0.0681%. The breakdown voltage and chop time of nanofluids were observed under standard lightning impulse waveform. The experimental results show that the presence of TiO2 nanoparticles increases the breakdown voltage of mineral oil under positive polarity. The enhancement of breakdown strength tends to saturate when the concentration of nanoparticle exceeds 0.0227 wt%. Electronic traps formed at the interfacial region of nanoparticles, which could capture fast electrons in bulk oil and reduce the net density of space charge in front of prebreakdown streamers, are responsible for the breakdown strength enhancement. When the particle concentration level is higher, the overlap of Gouy–Chapman diffusion layers results in the saturation of trap density in nanofluids. Consequently, the breakdown strength of nanofluids is saturated. Under negative polarity, the electrons are likely to be scattered by the nanoparticles on the way towards the anode, resulting in enhanced electric fields near the streamer tip and the decrement of breakdown voltage.

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Behavior of Biodegradable Oil under Impulse Voltages

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.785.320 ◽

2015 ◽

Vol 785 ◽

pp. 320-324 ◽

Cited By ~ 2

Author(s):

Nurul Izzatul Akma Katim ◽

Mohd Taufiq Ishak ◽

A.M. Ishak ◽

M.Z.A.A. Kadir

Keyword(s):

Breakdown Voltage ◽

Palm Oil ◽

Coconut Oil ◽

Mineral Oil ◽

Electrical Performance ◽

Uniform Field ◽

Testing Methods ◽

Environmental Compatibility ◽

Impulse Voltage ◽

Lightning Impulse

The properties of Palm Oil (PO) and Coconut Oil (CO) offer the potential for transformers with non-toxicity, high fire and flash points and better environmental compatibility while compared with those filled with Mineral Oil (MO). This potential has led to intensive studies of electrical performance of biodegradable oil especially in evaluating the electrical performance under lightning impulse voltage in recent years. This paper presents the investigation on the impulse breakdown voltage of PO and CO in such a uniform field. The PO used in this study is Refined, Bleached and Deodorized Palm Oil (RBDPO) Olein type. Two testing methods, rising-voltage and up-and-down are considered for both oils with different gap distances (2.0 mm and 3.8 mm). Testing methods including rising-voltage method and up-and-down method have no notable influence on the breakdown voltages of RBDPOs and CO compared to MO.

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A Promising Nano-Insulating-Oil for Industrial Application: Electrical Properties and Modification Mechanism

Nanomaterials ◽

10.3390/nano9050788 ◽

2019 ◽

Vol 9 (5) ◽

pp. 788 ◽

Cited By ~ 7

Author(s):

Jiaqi Chen ◽

Potao Sun ◽

Wenxia Sima ◽

Qianqiu Shao ◽

Lian Ye ◽

...

Keyword(s):

Breakdown Voltage ◽

Industrial Application ◽

Breakdown Strength ◽

Absorption Capacity ◽

Photon Absorption ◽

Electrical Performance ◽

Test Results ◽

Strong Electron ◽

Insulating Oil ◽

Lightning Impulse

Despite being discovered more than 20 years ago, nanofluids still cannot be used in the power industry. The fundamental reason is that nano-insulating oil has poor stability, and its electrical performance decreases under negative impulse voltage. We found that C60 nanoparticles can maintain long-term stability in insulating oil without surface modification. C60 has strong electronegativity and photon absorption ability, which can comprehensively improve the electrical performance of insulating oil. This finding has great significance for the industrial application of nano-insulating oil. In this study, six concentrations of nano-C60 modified insulating oil (CMIO) were prepared, and their breakdown strength and dielectric properties were tested. The thermally stimulated current (TSC) curves of fresh oil (FO) and CMIO were experimentally determined. The test results indicate that C60 nanoparticles can simultaneously improve the positive and negative lightning impulse and power frequency breakdown voltage of insulating oil, while hardly increasing dielectric loss. At 150 mg/L, the positive and negative lightning impulse breakdown voltages of CMIO increased by 7.51% and 8.33%, respectively, compared with those of FO. The AC average breakdown voltage reached its peak (18.0% higher compared with FO) at a CMIO concentration of 200 mg/L. Based on the test results and the special properties of C60, we believe that changes in the trap parameters, the strong electron capture ability of C60, and the absorption capacity of C60 for photons enhanced the breakdown performance of insulating oil by C60 nanoparticles.

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