Low-viscosity electrical insulating oil and preparation method thereof

Abstract

The invention discloses low-viscosity electrical insulating oil and a preparation method thereof, and relates to the technical field of insulating oil, and the low-viscosity electrical insulating oil is prepared from the following raw materials in parts by weight: 80-90 parts of base oil, 0.1-5 parts of an antioxidant, 1-8 parts of oleic acid coated inorganic heat-conducting particles and 1-8 parts of a viscosity modifier. According to the method disclosed by the invention, the problem of high viscosity of the insulating oil at low temperature caused by separation of the crystals is effectively reduced by carrying out breaking treatment on non-uniform and irregular crystals separated from the freezing points of the high-melting-point glyceride and wax in the base oil through ultrasonic waves. In addition, the super-hydrophilic adsorbent is adopted for adsorption treatment of the insulating oil, polar molecules of the insulating oil are greatly reduced, and therefore the volume resistivity of the insulating oil is improved. In addition, the oleic acid-coated inorganic heat-conducting particles are added, so that the heat conduction rate of the insulating oil can be increased, and the performance of electrical equipment is improved.

Description

Technical Field

[0001] The invention relates to the field of insulating oil, and in particular to low-viscosity electrical insulating oil and a preparation method thereof. Background Art

[0002] Electrical insulating oil is a kind of oil used in electrical equipment such as transformers and mutual inductors. It serves as both an insulating medium for electrical equipment and a heat-conducting medium for conducting heat energy of electrical equipment. It mainly plays the role of insulation and cooling. With the continuous development of the power industry, the power grid and power load are increasing, and users' safety requirements for electrical equipment such as transformers and oil are also increasing. In particular, power grids in remote and cold areas have put forward higher requirements on the low-temperature viscosity performance of oil-immersed transformers. However, the viscosity of existing insulating oils at the flow point or low temperature is not ideal, so it needs to be improved. Summary of the invention

[0003] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a low-viscosity electrical insulating oil and a preparation method thereof.

[0004] The technical solution of the present invention is as follows:

[0005] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0006] 80-90 parts of base oil, 0.1-5 parts of antioxidant, 1-8 parts of oleic acid coated inorganic thermal conductive particles, and 1-8 parts of viscosity modifier.

[0007] As a preferred embodiment of the present invention, the base oil comprises vegetable oil and mineral oil, and the vegetable oil accounts for 3-7% of the total mass of the base oil.

[0008] As a preferred embodiment of the present invention, the antioxidant is a phenolic antioxidant, specifically tert-butyl polyphenol, but not limited thereto.

[0009] As a preferred embodiment of the present invention, the viscosity modifier is a mixture of poly-α-olefin and polymethacrylate.

[0010] As a preferred embodiment of the present invention, a metal passivator is also included, which can be a methylbenzotriazole derivative, accounting for 0.1-0.5% of the mass of the base oil.

[0011] As a preferred embodiment of the present invention, the preparation method of the oleic acid-coated inorganic thermally conductive particles is as follows:

[0012] The inorganic thermal conductive particles are dispersed in an organic solvent, and then oleic acid is added and stirred to obtain.

[0013] The present invention also discloses a method for preparing low-viscosity electrical insulating oil, comprising the following steps:

[0014] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0015] As a preferred embodiment of the present invention, the preparation method of the super hydrophilic adsorbent is as follows:

[0016] The vermiculite is calcined at 600-900°C, then immersed in the mixed solution for 3-5 hours and dried.

[0017] As a preferred embodiment of the present invention, the mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate.

[0018] As a preferred embodiment of the present invention, the conditions of the ultrasonic treatment are: power of 50-200W, and ultrasonic time of 20-30min.

[0019] The beneficial effects of the present invention are:

[0020] The present invention uses ultrasound to break up the uneven and irregular crystals precipitated from the solidification point of high melting point glycerides and wax in the base oil, effectively reducing the problem of high viscosity of the insulating oil at low temperatures caused by the precipitation of the above crystals. In addition, the present invention uses a super-hydrophilic adsorbent to adsorb the insulating oil, greatly reducing the polar molecules of the insulating oil, thereby improving the volume resistivity of the insulating oil. In addition, the present invention adds oleic acid-coated inorganic thermal conductive particles, which can accelerate the thermal conductivity of the insulating oil, thereby improving the performance of electrical equipment. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. If no specific techniques or conditions are specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used that do not specify the manufacturer are all conventional products that can be obtained commercially.

[0022] Example 1

[0023] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0024] 80 parts of base oil, 0.2 parts of antioxidant, 3 parts of oleic acid coated inorganic thermal conductive particles, and 5 parts of viscosity modifier.

[0025] The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 3% of the total mass of the base oil.

[0026] The antioxidant is a phenolic antioxidant, specifically tert-butyl polyphenol.

[0027] The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate in a mass ratio of 3:1.

[0028] It also includes a metal deactivator, specifically a methylbenzotriazole derivative, accounting for 0.1% of the base oil mass.

[0029] The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows:

[0030] 3 parts by weight of inorganic thermally conductive particles are dispersed in 20 parts by volume of chloroform and sodium dodecylbenzenesulfonate (volume ratio 1:0.1), and then 8 parts by volume of oleic acid are added and stirred to obtain.

[0031] A method for preparing low-viscosity electrical insulating oil comprises the following steps:

[0032] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0033] The preparation method of the super hydrophilic adsorbent is as follows:

[0034] The vermiculite was calcined at 700°C, then immersed in the mixed solution for 3 h and dried.

[0035] The mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate in a mass ratio of 3:1:3:1.

[0036] The conditions of the ultrasonic treatment are: power of 180 W and ultrasonic time of 25 min.

[0037] Example 2

[0038] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0039] 85 parts of base oil, 1 part of antioxidant, 3 parts of oleic acid coated inorganic thermal conductive particles, and 5 parts of viscosity modifier.

[0040] The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 3% of the total mass of the base oil.

[0041] The antioxidant is a phenolic antioxidant, specifically tert-butyl polyphenol.

[0042] The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate in a mass ratio of 3:1.

[0043] It also includes a metal deactivator, specifically a methylbenzotriazole derivative, accounting for 0.2% of the base oil mass.

[0044] The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows:

[0045] 3 parts by weight of inorganic thermally conductive particles are dispersed in 20 parts by volume of chloroform and sodium dodecylbenzenesulfonate (volume ratio 1:0.1), and then 8 parts by volume of oleic acid are added and stirred to obtain.

[0046] A method for preparing low-viscosity electrical insulating oil comprises the following steps:

[0047] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0048] The preparation method of the super hydrophilic adsorbent is as follows:

[0049] The vermiculite was calcined at 750°C, then immersed in the mixed solution for 3 h and dried.

[0050] The mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate in a mass ratio of 3:1:3:1.

[0051] The conditions of the ultrasonic treatment are: power of 180 W and ultrasonic time of 25 min.

[0052] Example 3

[0053] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0054] 90 parts of base oil, 2 parts of antioxidant, 7 parts of oleic acid coated inorganic thermal conductive particles, and 3 parts of viscosity modifier.

[0055] The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 3% of the total mass of the base oil.

[0056] The antioxidant is a phenolic antioxidant, specifically tert-butyl polyphenol.

[0057] The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate in a mass ratio of 3:1.

[0058] It also includes a metal deactivator, specifically a methylbenzotriazole derivative, accounting for 0.3% of the base oil mass.

[0059] The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows:

[0060] 3 parts by weight of inorganic thermally conductive particles are dispersed in 20 parts by volume of chloroform and sodium dodecylbenzenesulfonate (volume ratio 1:0.1), and then 8 parts by volume of oleic acid are added and stirred to obtain.

[0061] A method for preparing low-viscosity electrical insulating oil comprises the following steps:

[0062] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0063] The preparation method of the super hydrophilic adsorbent is as follows:

[0064] The vermiculite was calcined at 800°C, then immersed in the mixed solution for 3 h and dried.

[0065] The mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate in a mass ratio of 3:1:3:1.

[0066] The conditions of the ultrasonic treatment are: power of 180 W and ultrasonic time of 25 min.

[0067] Example 4

[0068] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0069] 89 parts of base oil, 3 parts of antioxidant, 4 parts of oleic acid coated inorganic thermal conductive particles, and 5 parts of viscosity modifier.

[0070] The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 3-7% of the total mass of the base oil.

[0071] The antioxidant is a phenolic antioxidant, specifically tert-butyl polyphenol.

[0072] The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate.

[0073] It also includes a metal deactivator, specifically a methylbenzotriazole derivative, accounting for 0.4% of the base oil mass.

[0074] The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows:

[0075] 3 parts by weight of inorganic thermally conductive particles are dispersed in 20 parts by volume of chloroform and sodium dodecylbenzenesulfonate (volume ratio 1:0.1), and then 8 parts by volume of oleic acid are added and stirred to obtain.

[0076] A method for preparing low-viscosity electrical insulating oil comprises the following steps:

[0077] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0078] The preparation method of the super hydrophilic adsorbent is as follows:

[0079] The vermiculite was calcined at 700°C, then immersed in the mixed solution for 3 h and dried.

[0080] The mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate in a mass ratio of 3:1:3:1.

[0081] The conditions of the ultrasonic treatment are: power of 180 W and ultrasonic time of 25 min.

[0082] Example 5

[0083] A low-viscosity electrical insulating oil comprises the following raw materials in parts by weight:

[0084] 90 parts of base oil, 5 parts of antioxidant, 5 parts of oleic acid coated inorganic thermal conductive particles, and 7 parts of viscosity modifier.

[0085] The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 4% of the total mass of the base oil.

[0086] The antioxidant is a phenolic antioxidant, tert-butyl polyphenol.

[0087] The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate in a mass ratio of 4:1.

[0088] It also includes a metal deactivator, specifically a methylbenzotriazole derivative, accounting for 0.4% of the base oil mass.

[0089] The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows:

[0090] 3 parts by weight of inorganic thermally conductive particles are dispersed in 20 parts by volume of chloroform and sodium dodecylbenzenesulfonate (volume ratio 1:0.1), and then 8 parts by volume of oleic acid are added and stirred to obtain.

[0091] A method for preparing low-viscosity electrical insulating oil comprises the following steps:

[0092] The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

[0093] The preparation method of the super hydrophilic adsorbent is as follows:

[0094] The vermiculite was calcined at 700°C, then immersed in the mixed solution for 3 h and dried.

[0095] The mixed solution includes a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate in a mass ratio of 3:1:3:1.

[0096] The conditions of the ultrasonic treatment are: power of 180 W and ultrasonic time of 25 min.

[0097] Comparative Example 1

[0098] This comparative example is a variation of Example 2, specifically, no oleic acid-coated inorganic thermally conductive particles are added.

[0099] Comparative Example 2

[0100] This comparative example is a variation of Example 2, specifically, no ultrasonic treatment is performed.

[0101] Comparative Example 3

[0102] This comparative example is a variation of Example 2, specifically, no super-hydrophilic adsorbent is used for treatment.

[0103] The performance of the above embodiments and comparative examples were tested, and the test results are shown in Table 1.

[0104] Table 1 Performance test results of embodiments and comparative examples

[0105]

[0106]

[0107] As can be seen from the above table, the performance of the embodiment is better than that of the comparative example. The main reason may be that the oleic acid-coated inorganic thermally conductive particles are added in the embodiment, which can accelerate the thermal conductivity of the insulating oil, thereby improving the performance of the electrical equipment; the uneven and irregular crystals precipitated from the solidification point of the high melting point glycerides and wax in the base oil are broken by ultrasound, which effectively reduces the problem of high viscosity of the insulating oil at low temperatures caused by the precipitation of the above crystals; in addition, the present invention uses a super hydrophilic adsorbent to adsorb the insulating oil, which greatly reduces the polar molecules of the insulating oil, thereby improving the volume resistivity of the insulating oil.

[0108] The above-mentioned embodiments only express the preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all these changes and deformations should fall within the scope of protection of the claims of the present invention.

Claims

1. A low-viscosity electrical insulating oil, characterized in that: The invention comprises the following raw materials in parts by weight: 80-90 parts of base oil, 0.1-5 parts of antioxidant, 1-8 parts of oleic acid coated inorganic thermal conductive particles, and 1-8 parts of viscosity modifier.

2. A low-viscosity electrical insulating oil according to claim 1, characterized in that: The base oil includes vegetable oil and mineral oil, and the vegetable oil accounts for 3-7% of the total mass of the base oil.

3. The low-viscosity electrical insulating oil according to claim 1, characterized in that: The antioxidant is a phenolic antioxidant.

4. A low-viscosity electrical insulating oil and a preparation method thereof according to claim 1, characterized in that: The viscosity modifier is a mixture of poly-α-olefin and polymethacrylate.

5. The low-viscosity electrical insulating oil according to claim 1, characterized in that: It also includes a metal deactivator, a methylbenzotriazole derivative, accounting for 0.1-0.5% of the base oil mass.

6. The low-viscosity electrical insulating oil according to claim 1, characterized in that: The preparation method of the oleic acid coated inorganic thermally conductive particles is as follows: The inorganic thermal conductive particles are dispersed in an organic solvent, and then oleic acid is added and stirred to obtain.

7. A method for preparing low-viscosity electrical insulating oil, characterized in that: The following steps are involved: The base oil, antioxidant and oleic acid coated inorganic thermal conductive particles are firstly mixed uniformly, and then ultrasonically treated; while ultrasonicating, a viscosity adjuster and a super hydrophilic adsorbent are added for treatment, and after the treatment, the mixture is filtered to obtain the product.

8. The method for preparing a low-viscosity electrical insulating oil according to claim 7, characterized in that: The preparation method of the super hydrophilic adsorbent is as follows: The vermiculite is calcined at 600-900°C, then immersed in the mixed solution for 3-5 hours and dried.

9. The method for preparing a low-viscosity electrical insulating oil according to claim 8, characterized in that: The mixed solution comprises a mixed solution of sodium citrate, sodium tartrate, sodium hexadecyl sulfonate and disodium ethylenediaminetetraacetate.

10. The method for preparing a low-viscosity electrical insulating oil according to claim 7, characterized in that: The conditions of the ultrasonic treatment are: power of 50-200W, and ultrasonic time of 20-30min.

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