Production method of hybrid NANO-modified oil for power distribution transformers cooling system

Abstract

In this invention, nano technology and nano materials have been used to create a hybrid nano fluid oil to improve the cooling performance, electrical insulation and heat transfer in power transformers. In order to achieve an easy, fast, low-cost solution, a simple method was used to produce the nano-oil. The product is a hybrid of metal oxide nanoparticles and a wide range of surface stabilizers to stabilize the dispersion of particles. One of the aims of this invention is to increase the thermal conductivity of the oil which improves the heat transfer performance and to be poured directly into the tank of power distribution transformers. Another acheivement of this invention is the improvement in the physical and electrical properties of the oil, including density, viscosity, and dielectric breakdown point.

Description

Production Method of Hybrid Nano-modified oil for Power Distribution Transformers Cooling System

[0001] In this invention, cutting-edge nano technology and nano materials have been utilized to create a hybrid nano fluid oil that significantly enhances the cooling performance, electrical insulation, and heat transfer capabilities of power transformers. The key to this invention lies in the use of a simple mixing and dispersing method to produce the nano-oil, making it an easy, fast, and cost-effective solution for improving transformer efficiency. The hybrid nano fluid oil is a blend of metal oxide nanoparticles and a wide array of surface stabilizers that work together to effectively emulsify the dispersion of particles within the oil.

[0002] One of the primary goals of this invention is to boost the thermal conductivity of the oil, thereby enhancing its heat transfer performance and allowing it to be directly poured directly into the tank of power distribution transformers. Additionally, this innovative nano oil also improves the physical and electrical properties of the oil, including density, viscosity, and dielectric breakdown point.

[0003] Overall, this game-changing invention not only revolutionizes the way in which power transformers operate, but also paves the way for enhanced efficiency, reliability, and longevity in transformer systems. The use of nano technology in this context opens up a world of possibilities for future advancements in transformer technology and energy efficiency.

[0004] C10M 169 / 04 – C10N 40 / 16

[0005] CN104946355

[0006] NANO TRANSFORMER OIL

[0007] The invention provides nano transformer oil and a preparation method. By adding nano titanium dioxide particles adsorbing linoleic acid on the surface, the nano transformer oil provided by the invention has clear and transparent appearance and excellent anti-sedimentation stability and avoids obvious change observable to naked eyes after standing for a long time; moreover, the thermal conductivity is obviously optimized in practical application; with the temperature change, the thermal conductivity is increased to different degrees; the thermal conductivity of most liquid is reduced with the temperature increase while the thermal conductivity of the nano transformer oil provided by the invention is increased with the temperature increase, and the requirements of transformer oil on insulation and cooling are met.

[0008] The mentiond invention shares certain qualities with our claimed one, such as thermal conductivity optimization or the use of titanium dioxide. However, they use different methods and mechanisms to achieve the result and the other componants are not the same.

[0009] CN110669565

[0010] PREPARATION METHOD OF NANO MODIFIED TRANSFORMER OIL WITH HIGH BREAKDOWN VOLTAGE

[0011] The invention relates to a preparation method of nano-modified transformer oil with a high breakdown voltage, and the method comprises the following steps of: (1) taking ferromagnetic conductive nano-particles Fe3O4 and preparing modified ferromagnetic conductive nano-particles Fe3O4 after being treated by a surface modifier; the method has the beneficial effects that the ferromagnetic conductivenano-particles Fe3O4 are dispersed in transformer oil after being treated by the surface modifier to prepare the nano-modified transformer oil; through an operation impact breakdown test, the impact breakdown characteristic of the nano-modified transformer oil is improved to a greater extent than that of pure transformer oil except for the negative lightning impact condition, wherein the improvement range of the operation positive breakdown voltage can reach 44.1%. The improvement of the impact breakdown characteristic of the nano-modified transformer oil is related to the addition of the modified ferromagnetic conductive nano-particles Fe3O4 to capture electrons and change the original spatial electric field distribution, the breakdown voltage of the transformer oil is improved, the insulation is improved, and personal safety is ensured.

[0012] This mentioned patent bears a strong resemblance to our claimed one in the process of producing a nano-modified oil including dispersion and surface modifying. However, the componants are different and the primary focus here is on the use of ferromagnetic nanoparticles Fe3O4 while our method is applicable to a range of material.

[0013] CN105820859

[0014] PREPARATION METHOD OF TITANIUM DIOXIDE NANO-PARTICLE MODIFIED TRANSFORMER OIL

[0015] The invention relates to a preparation method of titanium dioxide nano-particle modified transformer oil, and belongs to the technical field of preparation of the transformer oil in the power industry. The preparation method of the titanium dioxide nano-particle modified transformer oil comprises the following steps: 1, performing surface treatment on TiO2 nano particles to obtain surface-wrapped TiO2; 2, mixing the modified TiO2 nano particles with transformer oil by an ultrasonic or ball grinding method, so as to finally prepare the available TiO2 nano-particle modified transformer oil. The TiO2 nano-particle modified transformer oil obtained by the preparation method disclosed by the invention is excellent in heat conduction performance and electric property, and is high in long-term stability, and the stability and the reliability in the service period are guaranteed.

[0016] This invention is very similar to our claimed method in their use of titanium dioxide and surface treatment to achieve optimized heat conduction in the transformer oil. While certain elements of the two methods are alike, other parts differ. For instance, unlike this patent, ours utilizes silicon dioxide, magnetic stirring and ice bath ultrasonic dispersion.

[0017] CN106544143 - NANO-MODIFIED TRANSFORMER OIL AND PREPARATION METHOD THEREOF

[0018] The invention belongs to the technical field of electricity, and particularly relates to nano-modified transformer oil and a preparation method thereof. The transformer oil is prepared from 0.15 to 0.8% of modified aluminium nitride nano-particles and 0.2 to 1.0% of modified alpha-Al2O3 nano-particles in percentage by weight. The nano-modified transformer oil is prepared by the following steps: adding aluminium nitride nano-particles and a silane coupling agent into an organic solvent to carry out sonic oscillation for 1 to 2h, then adding methyl methacrylate, carrying out water bath reaction at 60 to 80 DEG C for 10 to 12h, ball-milling, carrying out rotary evaporation for removing the organic solvent, drying, obtaining powder, then carrying out Soxhlet extraction with methylbenzene, and then carrying out devolatilization, thus obtaining the modified aluminium nitride nano-particles; modifying alpha-Al2O3 nano-particles with a sodium laurate solution to obtain the modified alpha-Al2O3 nano-particles; adding the modified nano-particles into base oil, then adding a molecular sieve for adsorption, and filtering. The nano-modified transformer oil prepared by the method has excellent heat-conducting property and electrical performance.

[0019] This mentioned patent resembles ours in their final product and overall function, but the methods of production and used ingredients are completely different. For example, while this one includes evaporation, drying and devolatization along with other elaborate processing phases, ours utilizes a simplified method of magnetic mixing and dispersing.

[0020] CN105647613 - METHOD FOR PREPARING ALUMINUM OXIDE NANO PARTICLE MODIFICATION TRANSFORMER OIL

[0021] The invention relates to a method for preparing aluminum oxide nano particle modification transformer oil and belongs to the technical field of electric power industry transformer oil preparation. The method comprises the steps of conducting surface treatment on Al2O3 nano particles to obtain surface-coated Al2O3; mixing modified Al2O3 nano particles with transformer oil with the ultrasonic method or ball milling method, and preparing the applicable Al2O3 nano particle modification transformer oil through vacuum heating treatment. The Al2O3 nano particle modification transformer oil obtained with the method has excellent heat-conducting property and electrical performance and high long-term stability, and stability and reliability in the using period are guaranteed.

[0022] This mentioned nano-modified oil product has the same functional qualities as ours but that is where the similarities end since the method, mechanisms and componants are different.

[0023] CN106590834

[0024] PREPARATION METHOD OF HIGH THERMAL CONDUCTIVITY TRANSFORMER OIL

[0025] The invention discloses a preparation method of high thermal conductivity transformer oil. The preparation method comprises the following steps: firstly, taking tetraethoxysilane, anhydrous ethanol, deionized water and ammonia water as raw materials, using a sol-gel method to prepare nano-silica, and adopting a carboxyl siloxane surfactant to carry out surface coating on the nano-silica, finally mixing the nano-silica coated by the carboxyl siloxane surfactant with transformer oil, and performing ultrasonic dispersion for 1 to 8h at the power of 1000W to obtain the high thermal conductivity transformer oil. The high thermal conductivity transformer oil prepared by the method can be stably stored for a long time and is excellent in thermal conductivity.

[0026] The patent mentioned above also uses ultrasonic dispersion and the final product is similar in function to our claimed one. However the methods of production and comprising materials are different.

[0027] In this patent, nano materials have been utilized to make a hybrid nano-oil that impoves the cooling mechanism, electrical insulation and heat transmission in power distribution transformers. In order to attain a simple, fast, low-cost solution, a method of magnetic blending and dispersion was utilized to deliver the nano-oil. The product is a hybrid of metal oxide nanoparticles and surface stabilizers to emulsify the dispersion of particles. One of the points of this development is to enhance transformer heat transmission and thermal conductivity of the system. The produced oil can be poured directly into the tank of power transmission transformers. Another advantage of this development is the enhancement of the physical and electrical properties of the oil, such as density, viscosity, and dielectric breakdown point.

[0028] Considering the need of the electricity industry for stability and increasing the efficiency of distribution transformers, as well as the need to reduce costs in power distribution plants in order to supply oil for transformers, there are issues that need to be resolved. Technical errors in the structure of the windings and malfunction of transformers due to the decrease in the quality of oil and the inability to transfer heat can be mentioned as major problems in the power distribution network. This invention attempts to address such issues in a way that with the use of this product, the thermal transfer properties of the system increases, and it directly affects the electrical properties and stability of transformers. Moreover, it makes it possible to ensure absolute stability in the power distribution system and reduce damage to transformers.

[0029] Nanostructured oils are usually synthesized by one-step and two-step methods. They can be prepared in a single-step method using methods such as steam accumulation of metal particles and metal oxide, laser wear, water-immersed electric arc, and other chemical and nucleation methods. In the two-step method, nanoparticles are synthesized in separate processes without the presence of fuel, and in the next step, these nanoparticles are dispersed in the fuel space with a variety of physical methods. The process of dispersing particles generally includes the use of a magnetic stirring device, a device that creates ultrasonic waves, adjusting the pH of the solution, or a combination of these methods. In general, two-step methods have been widely used in the preparation of nanostructured fuel supplements due to the ease of product preparation, and most of the processes described in national and international articles, researches, and inventions are of this type. The method is used as a standard method. It is important to mention that the use of the mentioned methods cannot be a claim regarding the novelty of the research, invention and article, but rather the method of preparing nano additives based on mineral transformer oil, including the type and grade (categorization) of the oil, steps, amount and the type of raw materials such as nanoparticles and stabilizing chemicals, the degree of stability of dispersed nanoparticles is important.

[0030] Production of oil with high heat transfer and breakdown voltage higher than base oils has always been one of the topics discussed in energy and power transmission. Nanomaterials have attracted a lot of attention in this field due to the large changes in the physical and chemical properties of fluids. Although the changes made on the physical and thermal properties of oils depend on the type of nanoparticles, the size of the particles, the type of stabilizers and emulsifiers, in general, nano additives cause an increase in oil density, breakdown voltage and more than 100% increase in the heat transfer of used oils.

[0031] Nanomaterials can usually be used in the form of nanoparticles, tubes, fibers and plates in all kinds of oils (mineral-vegetable). Until now, nanostructured oil supplements based on metal nanoparticles and metal oxides have been widely used in this field, which mostly include carbon nanotubes, titanium oxide, and silicon oxide, and they have been limited to study samples. In the field of oils, nanostructure has been used on motor oils, which is a commercial example by Chinese companies named Union Abrasive, Changzhouz Hexin Industry and Protech, and in domestic examples, there is no such product in the field of electricity and nanotechnology. And studies are generally involve applied nano-oils in car engines and vehicles, so there is an urgent need to prepare improved samples of transformer oils, especially inside. Existing samples lack specific appplicabiliy and use different mechanisms that do not involve the production method of nanofluids.Solution of Problem

[0032] According to the studies carried out and the review of prior art and the history of progress related to the invention, it can be seen that there has always been an effort to provide a new solution regarding transformers and even numerous articles have been presented, but still a new combination of materials and weight percentages have not been available in the manufacture of supplemental or independent nano-oil in order to increase the quality of transformer oil, and the current invention can be a strong step in solving operational problems in the electrical industry.

[0033] Despite the increasing development of researches in this field of nanotechnology to prepare the scaffolding of nano-oil products, however, providing a simple, fast and low-cost solution to prepare a supplement or sustainable nanostructured oil with special properties is strongly felt. In this regard, the leading invention considers the process of preparation and manufacturing of combined nanohybrid oil with improved properties as a way out of the economic and operational problems of the electricity industry caused by the explosion of transformers and also the rapid deterioration of oils in warmer regions.

[0034] As stated earlier, the researchers and inventors of this case have carried out a wide range of activities in other directions and have developed nanohybrid products based on the principle of combining the properties of nanostructures to produce oil supplements in various other industries and applications such as transportation, heavy vehicles (ships and trains) and power plants, but to show the performance of the inventive subject, only the results related to the use of a 2-component product with nanoparticles are presented in Table 1.

[0035] The composition of the percentage of each of these nanoparticles in the supplement or nanohybrid oil varies between 10-100ppm based on the performance characteristics of various power transformers or distribution power transmission plants and during the optimization process. Also, in order to create product stability, a wide range of surface stabilizers such as Oleic Acid, SPAN 60 and other long-chain organic compounds whose hydrophilic end has a positive, negative or neutral charge up to a maximum of 2.5% by volume individually or in combination will be added to the oil. It should be noted that the stability of the fuel is significantly dependent on the size of the particles, the amount of added particles, order and addition, concentration and type of surface stabilizer, but the products produced in this way will be stable for up to 5 months.

[0036] The product is created through a simple process, wherein the nanoparticles of specific size and amount are added to the transformer oil, stirred magnetically and dispersed on an ice bath using an ultrasonic device with a probe. The stirring phase is done in 3 fifteen minute rounds with 5 minute breaks in between and the dispersion takes 30 minutes. The size of the nanoparticles varies between 10-70 nm based on the characteristics of the equipment used (distribution and power transformer) and based on the weather conditions of each region. Thus, according to the demands of each project, the steps and ingredients of the method can be modified.

[0037] According to what has been stated about the technical problem, the solution aims to increase the quality and time efficiency of the transformer oil, and also the need to use distribution oil transformers in tropical regions and the damage to the distribution system during the hot seasons, to solve maintenance problems and create long-term replacement periods where reloading transformers will have high priority. Therefore, the current invention helps in improving the stability and conditions of the base oil by using the properties of metal oxide nanostructures.Advantage Effects of the Invention

[0038] 1) A low-cost, accurate and high-speed method for creating different types of nanohybrid / multicomponent oils compared to single-step methods (based on chemical, laser and electrical processes).

[0039] 2) The possibility of using the range of metal oxide nanoparticles along with surface stabilizers to create various products depending on the needs of the industry

[0040] 3) Taking advantage of the special properties of different metal oxide nanoparticles, relying on the principle of superimposition of properties in a composition and creating a nanohybrid supplement.

[0041] 4) Not using nanoparticles and chemicals with high toxicity and high risk in terms of environmental standards.

[0042] 5) Reproducibility of the results due to the simplicity of the production method and industrial production capability.

[0043] 6) The possibility of quick and accurate design of supplement or nano-oil based on the size, concentration of nanoparticles and stabilizing materials, as well as optimization according to the needs of the power transmission system.

[0044] 7) No need for any modification in the settings and structure of transformers

[0045] 8) Mineral oil base that makes the product easy to use in the oil tank

[0046] Shows a general flowchart of the hybrid nano-oil production process.

[0047] Shows a general flowchart of the proposed production process wherein the components and mechanisms of the claimed method and the connection between them can be seen. The nanoparticles used in this method need to be selected with specific size and amounts according to the transformer equipment and weather of the region. The nanoparticles can be between 10-100ppm and 10-70nm, and they may include SiO and TiO2. Surface stabilizers should also be added to the oil base, in less than 2.5% quantities. The proposed method can function with a wide range of stabilizers, including Oleic acid and SPAN60. After they are added to the oil, the magnetic stirring is performed, then the dispersion is done on an ice bath using an ultrasonic device to achieve the result.Examples

[0048] This invention involves the production method for transformer oil using nanoparticles wherein a magnetic stirrer is used to achieve the final product.

[0049] [Pic. 1] Here the general process of nanohybrid oil preparation can be seen.

[0050] [Pic. 1]

[0051]

[0052] [Pic. 2] Here the electron microscope images of prepared metal oxide nanoparticles is shown.

[0053] [Pic. 2]

[0054]

[0055] The list of materials used to prepare a type of nanohybrid supplement is displayed below:

[0056] [Table 1] The ingredients of the nanohybrid supplement

[0057]

[0058] The list of equipment and machines used in the process is shown below:

[0059] [Table 2] Equipment and devices used

[0060]

[0061] The individual behavior of the ingredient used in the process is captured below:

[0062] [Table 3] Summary of expected properties from the presence of each nanoparticle in diesel fuel individually

[0063]

[0064] More specific details are displayed below:

[0065] [Table 4] The effect of different nanoparticles on the physical and professional properties of a hybrid nano oil with four nanoparticle components totaling 60 ppm and 2.5% by volume of oleic acid surface stabilizer.

[0066]

[0067] This patent may be very widely used in the electricity industry and power distribution units of any country. More specifically, this invention can be manufactured and supplied in 20 liter gallons, just like base oils, and after purchase, it can be injected into distribution and power transformers.

Claims

A production method is designed for a hybrid nanofluid supplement based on transformer oil using specific metal oxide nanoparticles and surface stabilizers.According to claim 1, the amount of nanoparticles varies between 10-100 ppm based on the size of the particles as well as the equipment used (distribution and power transformer).According to claim 1, the size of the nanoparticles varies between 10-70 nm based on the characteristics of the equipment used (distribution and power transformer) and based on the weather conditions of each region.According to claim 1, the nanoparticles used in the claimed method are titanium oxide and silicon oxide, which are prepared in hybrid form.According to claim 1 , the surface stabilizers, based on the type, amount and size of nanoparticles added, can include a variety of stabilizing materials such as Oleic acid, SPAN60, etc., which are added to the base oil at a maximum of 2.5% by volume.According to claim 1, the hybrid nano-oil is made via a method, wherein the nanoparticles added to the transformer oil, are first stirred by a magnetic stirrer three times for 15 minutes with a 5-minute break each turn, then the mix is dispersed on an ice bath for 30 minutes using an ultrasonic device with a probe.According to claim 1, the surface stabilizers will keep the supplement stable up to a maximum of 5 months.According to claim 1, the hybrid product can be used directly without the need to make changes in the distribution and power transformer.According to claim 1, the hybrid nano-oil can be designed using different combinations of nanoparticles, particle size and stabilizers according to the needs of power distribution transformers in each region.According to claim 1, the hybrid nano-oil can also be used as a supplement.According to claim 1, the hybrid nano oil supplement, depending on the amount, composition and size of added nanoparticles, can increase the voltage number up to 7%.According to claim 1, the hybrid nano oil supplement, depending on the amount, composition and size of added nanoparticles, can increase the amount of heat transfer and cooling up to 10%.

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