Synthetic transformer oil and preparation method and application thereof
Synthetic transformer oil was prepared by compounding polyalphaolefin base oil with mineral oil and adding aromatic compounds, which solved the problems of poor low-temperature performance and flammability of mineral oil, and achieved high-temperature safety and low-cost transformer oil application.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA PETROLEUM & CHEMICAL CORP
- Filing Date
- 2024-12-18
- Publication Date
- 2026-06-19
AI Technical Summary
Existing mineral-based transformer oils have poor low-temperature performance, low flash point, are flammable, and are prone to decomposition under high temperature and high electric field conditions, resulting in insufficient transformer safety and stability.
Synthetic transformer oil is prepared by blending polyalphaolefin base oil with mineral oil and adding aromatic compounds and antioxidants, meeting the national standards for low-temperature performance, flash point and gas evolution.
It improves the low-temperature fluidity and safety of transformer oil, expands its application range, reduces costs, and meets the standards of GB 2536-2011, IEC 60296:2020 and ASTM D3487-24.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of transformer oil technology, specifically relating to a synthetic transformer oil, its preparation method, and its application. Background Technology
[0002] A transformer is an electrical device used for power conversion. Transformer oil, as an indispensable component of a transformer, primarily serves functions such as insulation, heat dissipation, and arc suppression. During transformer operation, the oil temperature rises with the increase in operating load, typically remaining above 60℃ under normal conditions. To ensure the efficient operation of the transformer's coils, windings, regulators, switches, circuit breakers, and other mechanical components, the transformer oil must possess good fluidity and thermal conductivity. Transformer oil is filled between high-voltage electrodes. To prevent arcing and breakdown under the influence of a high-voltage electric field, the transformer oil must have excellent insulation properties. Simultaneously, the periodic changes in AC electrodes cause energy loss, which is measured using the dielectric loss factor. To minimize energy loss during power transmission, the selected transformer oil must have a low dielectric loss factor. Trace amounts of unstable components in the transformer, under high temperature, strong electric field, and the catalysis of metallic components, easily react with oxygen and moisture in the air to form sludge or polar compounds, leading to a decrease in insulation performance and ultimately transformer breakdown and failure. Therefore, when selecting transformer oil, it is essential to consider its comprehensive performance in all aspects to ensure the safe, stable, and long-term operation of the transformer.
[0003] In recent years, with the advancement of power grid construction and renovation projects, the demand for transformer oil has continued to grow. Currently, the market mainly offers two types: mineral oil and synthetic oil. Mineral oil dominates the market due to its lower cost, but its low-temperature performance is affected by its composition, resulting in poor low-temperature performance. Furthermore, mineral oil transformer oil has a low flash point (generally below 140℃), and the high temperature of the transformer arc can cause it to rapidly decompose, vaporize, and flash-ignite, leading to combustion accidents. PAO base oil, short for Poly Alpha Olefins, is a synthetic base oil. It is made from α-olefins produced by the polymerization of ethylene, which are then further polymerized and hydrogenated. Summary of the Invention
[0004] To address the current problems with transformer oil, this application provides a synthetic transformer oil, its preparation method, and its application. The synthetic transformer oil is prepared by blending polyalphaolefin base oil with mineral oil and adding aromatic compounds. The prepared synthetic transformer oil meets the requirements of national standards GB 2536-2011, IEC 60296:2020, and ASTM D3487-24 in terms of low-temperature performance, density, flash point, gas evolution properties, and polycyclic aromatic hydrocarbon content.
[0005] The technical solution of this application is as follows.
[0006] The first aspect of this invention provides a synthetic transformer oil.
[0007] The synthetic transformer oil includes base oil and aromatic compounds;
[0008] The base oil comprises polyalphaolefin base oil and mineral oil; the polyalphaolefin base oil comprises C16 to C24 olefins; and according to GB / T 265, the kinematic viscosity of the polyalphaolefin base oil at 40°C is 9 to 11 mm. 2 / s;
[0009] The aromatic compounds are selected from biphenyl compounds and benzyltoluene compounds.
[0010] Polyalphaolefin base oils exhibit good viscosity-temperature properties and low-temperature fluidity. By adding polyalphaolefin base oils to mineral oils and using auxiliary aromatic compounds, transformer oils can be synthesized, achieving a kinematic viscosity of 1066 mmHg at -40°C. 2 / s(NB / SH / T 0837), pour point can reach -48℃(GB / T 3535), flash point (closed cup) is 159℃-173.5℃(GB / T 261).
[0011] By blending with mineral oil, costs are reduced and the limitations of mineral oil in transformer oil applications are mitigated. Furthermore, there are no special requirements for the mineral oil, and the polyalphaolefin base oil in this application exhibits high compatibility.
[0012] In some embodiments of this application, the mineral oil includes mineral-based base oils with a distillation range of 270°C to 470°C.
[0013] In some embodiments of this application, the mineral-based base oil is derived from the hydrorefining process of crude oil and / or petroleum.
[0014] In some embodiments of this application, the mineral oil is added in an amount of 0 to 50 wt% of the transformer oil.
[0015] In some embodiments of this application, the benzyltoluene includes hydrogenated terphenyl and benzyltoluene;
[0016] In some embodiments of this application, the amount of the aromatic compound added is 0.1 to 10 wt% of the transformer oil.
[0017] The aromatic compounds of this application can be combined with polyalphaolefin base oil and mineral oil to ensure that the resulting transformer oil has a gas evolution rate of less than 30, thus expanding the applicability of the transformer oil.
[0018] In some embodiments of this application, the synthetic transformer oil further includes an antioxidant; the amount of antioxidant added is 0.20 wt% to 0.35 wt% of the transformer oil weight.
[0019] In some embodiments of this application, the antioxidant includes phenolic antioxidants, preferably 2,6-di-tert-butyl-p-cresol.
[0020] In some embodiments of this application, the flash point of the synthetic transformer oil is higher than 155°C; preferably, according to GB / T 261, the flash point of the transformer oil is between 155°C and 175°C; more preferably, the flash point of the transformer oil is between 159°C and 174°C.
[0021] In some embodiments of this application, the kinematic viscosity of the synthetic transformer oil at 40°C, as determined according to GB / T 265, is 12 mm². 2 Below / s, preferably 10-12mm 2 / s, more preferably 10.26~11.25mm 2 / s; kinematic viscosity at -10℃ at 1800 mm 2 Below / s, preferably 90-200mm 2 / s, more preferably 94–117 mm 2 / s; kinematic viscosity at -20℃ at 1800 mm 2 / s or less, preferably 1180-300 mm 2 / s, more preferably 180–245 mm 2 / s.
[0022] In some embodiments of this application, the pour point of the synthetic transformer oil, as determined by GB / T 3535, is 0 to -50°C, preferably -27°C to -48°C.
[0023] In some embodiments of this application, the density of the synthetic transformer oil at 20°C, as determined by SH / T 0604, is no greater than 895 kg / m³. 3 Preferably, the weight is no more than 830 kg / m³. 3 More preferably 800 kg / m 3 ~830kg / m 3 .
[0024] A second aspect of this invention protects a method for preparing the above-mentioned synthetic transformer oil, the method comprising mixing a mineral-based base oil with an optional distillation range of 270°C to 470°C, a polyalphaolefin base oil, an optional antioxidant, and an aromatic compound.
[0025] The third aspect of this invention protects the application of the above-described synthetic transformer oil or the synthetic transformer oil prepared by the above method in transformers.
[0026] All of the above-mentioned raw materials used in this invention can be prepared in-house or purchased commercially; this invention does not impose any particular limitations on them.
[0027] Beneficial effects of the present invention
[0028] This invention uses polyalphaolefin base oil or mineral oil with added polyalphaolefin base oil, antioxidants and aromatic compounds to develop transformer oil products that meet the requirements of national standard GB 2536-2011, IEC 60296:2020 and ASTM D3487-24, thus solving the problem of poor low-temperature performance of mineral-based transformer oil. Detailed Implementation
[0029] To make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments. These embodiments are for illustrative purposes only and are not limited to the scope of application of the present invention.
[0030] Example 1
[0031] Transformer oil is blended in different proportions. The specific preparation process is as follows: mineral oil with a distillation range of 270℃~470℃, polyalphaolefin base oil, antioxidants and aromatic compounds are mixed.
[0032] The mineral oil is a mineral-based base oil with a distillation range of 270℃ to 470℃ obtained from the hydrorefining process of crude oil and / or petroleum at Sinopec Gaoqiao Company.
[0033] The specific components of the examples and comparative examples are shown in Table 2.
[0034] Table 2 Transformer oil samples and comparative formulations
[0035]
[0036]
[0037] The effects of the transformer oils prepared in Examples 1 and 2 are analyzed, as detailed in Table 3.
[0038] Table 3 Performance Analysis of Synthetic Transformer Oil (Samples 1 and 2)
[0039]
[0040]
[0041] As can be seen from Table 3, the synthetic transformer oil obtained in this application complies with the relevant standards specified in the standard, is applicable to transformer applications under various conditions, and complies with domestic and international standards.
[0042] The effects of the transformer oils prepared in Comparative Examples 1-3 are analyzed, as detailed in Table 4.
[0043] Table 4 Performance Analysis of Synthetic Transformer Oil (Samples 3-6)
[0044]
[0045]
[0046] As shown in Table 4, Sample 6, prepared using hydrogenated terphenyl as the aromatic compound in Comparative Example 4, did not meet the requirements for gas evolution. Comparative Example 1, which did not contain polyalphaolefin base oil, failed to meet several requirements, such as gas evolution, pour point, and kinematic viscosity at -30°C. Comparative Examples 2 and 3, which used polyalphaolefin base oils, did not meet the requirements due to their low molecular weight. Some data (kinematic viscosity at -30°C and pour point) did not meet the standard requirements.
[0047] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.
Claims
1. A synthetic transformer oil, characterized in that, The synthetic transformer oil includes base oil and aromatic compounds; The base oil includes polyalphaolefin base oil and mineral oil; The polyalphaolefin base oil comprises C16 to C24 olefins; according to GB / T 265, the kinematic viscosity of the polyalphaolefin base oil at 40°C is 9 to 11 mm. 2 / s; The aromatic compounds are selected from biphenyl compounds and benzyltoluene compounds.
2. The synthetic transformer oil according to claim 1, wherein the mineral oil comprises a mineral-based base oil with a distillation range of 270℃ to 470℃; And / or, the mineral-based base oil is derived from the hydrorefining process of crude oil and / or petroleum; And / or, the mineral oil accounts for 0.1 to 50 wt% of the synthetic transformer oil.
3. The synthetic transformer oil according to claim 1 or 2, characterized in that, The polyalphaolefin base oil contains C 16 H 32 C 18 H 36 C 20 H 40 and C 24 H 48 At least one of them.
4. The synthetic transformer oil according to any one of claims 1-3, characterized in that, The aromatic compound is selected from hydrogenated terphenyl and benzyltoluene; And / or, the amount of the aromatic compound is 0.1 to 10 wt% of the synthetic transformer oil.
5. The synthetic transformer oil according to any one of claims 1-4, characterized in that, The synthetic transformer oil also includes antioxidants.
6. The synthetic transformer oil according to claim 5, characterized in that, The amount of the antioxidant is 0.20 wt% to 0.35 wt% of the synthetic transformer oil; and / or, the antioxidant includes phenolic antioxidants, preferably 2,6-di-tert-butyl-p-cresol.
7. The synthetic transformer oil according to any one of claims 1-6, characterized in that, The flash point of the synthetic transformer oil is higher than 155°C; preferably, according to GB / T 261, the flash point of the synthetic transformer oil is 155°C to 175°C; more preferably, the flash point of the transformer oil is 159°C to 174°C. And / or, according to GB / T 265, the kinematic viscosity of the synthetic transformer oil at 40°C is 12 mmHg. 2 Below / s, preferably 10-12mm 2 / s, more preferably 10.26~11.25mm 2 / s; kinematic viscosity at -10℃ at 1800 mm 2 Below / s, preferably 90-200mm 2 / s, more preferably 94–117 mm 2 / s; kinematic viscosity at -20℃ at 1800 mm 2 / s or less, preferably 1180-300 mm 2 / s, more preferably 180–245 mm 2 / s.
8. The synthetic transformer oil according to any one of claims 1-7, characterized in that, According to GB / T3535, the pour point of the synthetic transformer oil is 0 to -50℃, preferably -27℃ to -48℃. And / or, according to SH / T 0604, the density of the synthetic transformer oil at 20°C is not greater than 895 kg / m³. 3 Preferably, the weight is no more than 830 kg / m³. 3 More preferably 800 kg / m 3 ~830kg / m 3 .
9. The method for preparing the synthetic transformer oil according to any one of claims 1-8, characterized in that, The preparation method includes mixing a polyalphaolefin base oil, an optional mineral-based base oil with a distillation range of 270°C to 470°C, an optional antioxidant, and an aromatic compound.
10. A transformer, wherein the transformer is coated with synthetic transformer oil according to any one of claims 1-8 or synthetic transformer oil prepared by the preparation method according to claim 9.