Investigation of the Properties of Sunflower Oil with Antioxidants and Nano Powders
S. Uma Devi
PG-Scholar, Department of EEE,
National Engineering College,
Dr. S. Senthil Kumar
Assistant Professor, Department of EEE,
National Engineering College,
Abstract— In the creative modern world, we cannot live without electrical energy. The requirement is increasing day by day due to the increase in population. The requirement is determined by the petroleum oil by-products. In the recent research, petroleum will be available only for a few 100 years. So we have to make an alternate solution. In order to meet out that, Sunflower Oil is used. Sunflower Oil is the natural ester oil and its availability is easy. In order to improve the properties Antioxidants such as Selenium, Beta Carotene and TBHQ (tert-butylhydroquinone) is used and Nanopowders such as Aluminum Nitride and Carbon Nanopowders are used. Antioxidants used here is both natural and synthetic antioxidants. This work is mainly focused on finding an alternate solution of mineral oil as Sunflower Oil by adding some additives. The viscosity of the Sunflower Oil is also very low so it suitable for the transformer oil. Different proportions of Antioxidants and Nano Powders are chosen with different combinations. The properties such as Breakdown Voltage, Viscosity, Flash Point and Fire Point are measured as per the standards. Viscosity readings are taken for both 40oC and 90oC. Moreover, the Sunflower Oil mixed with Nanopowder combination gives the better result. The Sunflower Oil is biodegradable and it does not cause any damage to the environment. By using the Sunflower Oil the overall lifetime of the transformer is increased and it meets out the requirements for a high-temperature insulation fluid.
Keywords-Antioxidants; Nanopowders; Breakdown Voltage; Flash Point; Fire Point; Viscosity; tert-butylhydroquinone; Selenium; Beta Carotene; Aluminum Nitride; Carbon nanopowder
The transformer is the heart of the power system and it is very much necessary for boosting the efficiency. The transformer is the most important equipment for delivering electrical power supply to the consumers. The transformer works on the principle of electromagnetic induction, in which emf is induced and secondly the magnetic flux is generated by the voltage and current flowing in the primary coil winding. In the transformer insulation is the most important component. There are two basic insulation types. They are solid and liquid. For solid insulation, we use paper, pressboard, and epoxy. Among them, Kraft paper is the most famous one.
For liquid insulation purpose, we are using petroleum-based oil. We are using mineral oil. Good oil should have low viscosity value because it should have an easy flow to avoid becoming tight. Mineral oil is used in transformer for cooling purpose and insulation. But mostly it is used for insulation purpose. Due to the minimization of the available of petroleum, there is a demand for mineral oil. In order to overcome that we are using Sunflower Oil is biodegradable, nontoxic, thermostable, readily disposable and not hazardous to the environment. Temperature, oxygen availability and catalyst presence are the factors that influence the chemical stability of the oil. Power Transformer is the significant part of the electrical power grid system for safe and reliable operation of the electrical network systems.
Fig. I Coil Energized In The Transformer
The scope of the project is to measure the breakdown voltage of the Sunflower oil and to find the composition of oil having better characteristics. Antioxidants are used in order to avoid the oxidation stability and to remove the free radicals. To select the Antioxidants and Nanopowders with correct proportion and to prepare the fluid by adding required quantity of Antioxidants and Nanopowders with the oil samples. The correct proportion for nanopowders is determined by using the formula which is explained below. This work focuses on enhancing the parameters of the Sunflower oil by adding natural antioxidants, Synthetic antioxidants, and nanopowders.
II. Antioxidants And Nanopowders
Both natural and synthetic antioxidants are used in food industry for food additives to prolong their life and attractiveness. In order to delay or slow down the oxidation process antioxidants are used. There are two types of antioxidants they are natural antioxidants and synthetic antioxidants. When antioxidants are used it will improve the properties of the oil samples. The elimination of the free radical chain is done by the antioxidants.
Antioxidants + Oxygen = Oxidized Antioxidant
The natural antioxidant used here is Selenium and the synthetic antioxidant used here is TBHQ and Beta Carotene is used. The antioxidants and their nature, density, melting temperature and chemical formula are shown in TABLE I.
TABLE I. Antioxidants
Melting Temperature (o C)
Nanotechnology deals with structures sized between 1 to 100 nanometers at least in one dimension. Nowadays nanopowders are very important criteria for improving the property of the transformer oil. The nano powders used here is Aluminum Nitride and Carbon Nano powder. The proportion of adding the nano powder to the sample oil is determined by the below formula.
Weight of the nano powder (g) = ((Density of the nano powder (g/cm3) * Volume of the oil (ml)) / (Volume fraction the nanopowder (%)
The nanopowder and their density and molecular weight are shown in TABLE II.
TABLE II. Nanopowders
Molecular weight (g/mol)
Sunflower Oil (SO) is very essential Vitamin E oil and is obtained from the Sunflower plant. It is very easily available. The sunflower oil is taken in a beaker and the blending process is done. The blending process is after the antioxidants or nanopowders is added the oil in the beaker is stirrer with 700 rpm for 40 minutes and then it is filtered by using filter paper which completes the blending process. Then the oil is tested for various properties.
Fig. II Blending Process of the Sunflower Oil
The below TABLE III shows the different oil samples with their proportion combination of antioxidants and nanopowders and their names.
TABLE III. Sample Preparation
500 ml SO
500 ml SO + 1 g TBHQ
500 ml SO + 1 g Selenium
500 ml SO + 1 g Beta Carotene
500 ml SO + 0.5 g Selenium + 0.5 g Beta Carotene
500 ml SO + 0.5 g Selenium + 0.5 g TBHQ
500 ml SO + 0.5 g Beta Carotene + 0.5 g TBHQ
500 ml SO + 0.3 g Selenium +0.3 g Beta Carotene + 0.3 g TBHQ
500 ml SO + 2.5 g Aluminum Nitride
500 ml SO + 1.06 g Carbon Nanopowder
500 ml SO + 0.96 g Aluminum Nitride + 0.96 g Carbon Nanopowder
IV. Results And Discussions
The results of breakdown voltage, flash Point, fire Point and viscosity at 40oC and 90oC is discussed for natural Antioxidants, Synthetic Antioxidants and Nanopowders.
Fig. III Samples Prepared using Sunflower Oil
A. Breakdown Voltage
The Breakdown voltage is tested by using the Breakdown Voltage Kit equipment as per the IEC 60156 Standard. The Breakdown Voltage is determined to find the withstanding capacity and it is also called as the dielectric strength of the oil. The Breakdown Voltage of the oil samples varies from 20.9kV to 41kV. The below TABLE IV represents the Breakdown Voltage values for different oil samples and FIGURE IV represents the comparison of Breakdown Voltage of different oil samples.
TABLE IV. Brreakdown Voltage Values of Different Oil Samples
Breakdown Voltage (kV)
Fig. IV Comparison of Breakdown Voltage Values of Different Oil Samples
B. Flash Point
The Flash Point is tested by using the Pensky Martin Closed Cup Method equipment as per the ASTM D-93 Standard. The Flash Point of the oil samples varies from 305o C to 345 o C. The below TABLE V represents the Flash Point values for different oil samples and FIGURE V represents the comparison of Flash Point of different oil samples.
TABLE V. Flash Point Values of Different Oil Samples
Flash Point (o C)
Fig. V Comparison of Flash Point Values of Different Oil Samples
C. Fire Point
The Fire Point is tested by using the Pensky Martin Closed Cup Method equipment as per the ASTM D-93 Standard. The Fire Point of the oil samples varies from 323o C to 363 o C. The below TABLE VI represents the Fire Point values for different oil samples and FIGURE VI represents the comparison of Fire Point of different oil samples.
TABLE VI. FIRE Point Values of Different Oil Samples
Fire Point (o C)
Fig. VI Comparison of Fire Point Values of Different Oil Samples
The Viscosity is tested by using the Redwood Viscometer equipment as per the ASTM D-445 Standard. The Viscosity of the oil sample is measured for both 40 o C and 90 o C. The viscosity value for 40 o C gets reduced from 115.31 o C to 42.66 o C and for 90 o C it gets reduced from 55.1 o C to 20.93oC. The below TABLE VII represents the Viscosity values for different oil samples at 40 o C and FIGURE VII represents the comparison of Fire Point of different oil samples at 40 o C and TABLE VIII represents the Viscosity values for different oil samples at 90 o C and FIGURE VIII represents the comparison of Fire Point of different oil samples at 90 o C.
TABLE VII. Viscosity Values of Different Oil Samples At (40oC)
Viscosity at 40o C
Fig. VII Comparison of Viscosity Values of Different Oil Samples At 40oC
TABLE VIII. Viscosity Values of Different Oil Samples At (90oC)
Viscosity at 90o C
Fig. VIII Comparison of Viscosity Values of Different Oil Samples At 90oC
From the entire sample it is concluded that
1) The breakdown voltage is increased after the addition of Antioxidants and Nanopowders.
2) The flash point and fire point values are also increased and the viscosity values get reduced.
3) This approach is also useful in avoiding the harmful disposal of used mineral oil to the environment.
4) The regenerated oil increases the lifetime of the transformer and it is non toxic.
5) When the Sunflower Oil is mixed with nanopowder it gives better result when compared to antioxidants.
Overall investigation concludes that the enhanced oils using regenerative materials, nanopowders and antioxidants is an appropriate solution for potential reuse in power transformer.
VI. Future Scope
1) Additionally critical parameters such as pour point, acidity, IR image, water content, density, dissipation factor etc can be determined.
2) Analyzing the properties of the oil using soft computing techniques.
3) It also tends to the measurement of critical parameters on ester oil, vegetable oil after the addition with a different combination of antioxidants, nanopowders and absorbents.
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