阅读说明：本技术 一种电动汽车电机用耐atf油、耐电晕漆包线及其制备方法 (ATF oil-resistant corona-resistant enameled wire for electric automobile motor and preparation method thereof ) 是由 徐伟红 夏宇 周成 李果 于 2020-04-14 设计创作，主要内容包括：本发明公开了一种电动汽车电机用耐ATF油、耐电晕漆包线及其制备方法,属于绝缘材料领域。其中耐ATF油、耐电晕漆包线,包括铜导体与绝缘层,而绝缘层由内到外依次为耐油耐电晕防护涂层、耐电晕聚酰胺酰亚胺涂层、耐油耐电晕防护涂层、耐电晕聚酰胺酰亚胺涂层、耐油耐电晕防护涂层。本发明的耐ATF油、耐电晕漆包线具有应用工艺性好、耐电晕性能优异、耐ATF油,制造成本低等优势,适用于油冷型电动汽车电机散绕组线圈的制备。(The invention discloses an ATF oil-resistant and corona-resistant enameled wire for an electric automobile motor and a preparation method thereof, and belongs to the field of insulating materials. The ATF oil-resistant and corona-resistant enameled wire comprises a copper conductor and an insulating layer, wherein the insulating layer is sequentially provided with an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating, an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating and an oil-resistant and corona-resistant protective coating from inside to outside. The ATF oil-resistant and corona-resistant enameled wire has the advantages of good application manufacturability, excellent corona resistance, ATF oil resistance, low manufacturing cost and the like, and is suitable for preparing the motor bulk winding coil of the oil-cooled electric automobile.)

1. The utility model provides an ATF oil resistant, corona resistant enameled wire for electric automobile motor, includes copper conductor and insulating layer, its characterized in that: the insulating layer is sequentially provided with an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating, an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating and an oil-resistant and corona-resistant protective coating from inside to outside.

2. The enameled wire according to claim 1, wherein: the oil-resistant and corona-resistant protective coating, the corona-resistant polyamideimide coating, the oil-resistant and corona-resistant protective coating, the corona-resistant polyamideimide coating and the oil-resistant and corona-resistant protective coating respectively account for 5-12 percent of the coating thickness, 30-45 percent of the coating thickness, 5-12 percent of the coating thickness, 30-45 percent of the coating thickness and 5-12 percent of the coating thickness.

3. The enameled wire according to claim 2, wherein: the coating thickness ratio of 5 to 8 percent, 35 to 40 percent, 6 to 9 percent, 38 to 40 percent and 8 to 10 percent respectively.

4. The enamel wire according to any of claims 1 to 3, characterized in that: the corona-resistant polyamideimide coating is formed by coating corona-resistant polyamideimide wire enamel prepared by modifying nano silicon dioxide and/or aluminum oxide.

5. The enameled wire according to claim 4, wherein: the average grain diameter of the nano silicon dioxide and the aluminum oxide is 40-60 nm.

6. The enamel wire according to any of claims 1 to 3, characterized in that: the oil-resistant corona-resistant protective coating is formed by coating nano particle modified engineering plastic paint, wherein the preparation method of the paint comprises the following steps:

(1) adding a dispersing agent into N, N-dimethyl pyrrolidone for dispersion, then adding an inorganic filler for emulsification, and then cooling to obtain nano slurry;

(2) adding the nano slurry obtained in the step (1) into an engineering plastic solution, stirring, and then grinding to obtain a material 1;

(3) and (3) adding N, N-dimethyl pyrrolidone into the material 1 obtained in the step (2), and stirring to obtain the nano particle modified engineering plastic paint.

7. The enameled wire according to claim 6, wherein: the mass ratio of the N, N-dimethyl pyrrolidone, the dispersing agent and the inorganic filler in the step (1) is 18-30:1: 20-28.

8. The enameled wire according to claim 6, wherein: the engineering plastic in the step (2) is one or more of polycarbonate, polyformaldehyde, polyphenylene sulfide, polyether sulfone and polyether ether ketone.

9. The enameled wire according to claim 6, wherein: the milled particle size D50<100nm as described in step (2).

10. The method for preparing an enamel wire according to claim 1, comprising the steps of:

s1: paying off a copper conductor; s2: annealing at 490 deg.C/470 deg.C for 20-150 s; s3: painting by a mould method; s4: baking at 560 ℃ and 580 ℃ for 3-10 min; s5: cooling and monitoring on-line pinholes; s6: and (6) automatically collecting the disc.

Technical Field

The invention belongs to the field of insulating materials, and particularly relates to an ATF oil-resistant and corona-resistant enameled wire for an electric automobile motor and a preparation method thereof, in particular to an ATF oil-resistant and corona-resistant enameled wire and a preparation method thereof, which are mainly applied to preparation of a scattered winding coil of an oil-cooled electric automobile motor.

Background

The cooling mode of the electric automobile motor is divided into a water cooling mode and an oil cooling mode. The oil cooling type is cooled by using transmission oil (ATF oil), in the using process, an insulating material is directly contacted with the ATF oil, and part of the insulating material is corroded by the ATF oil for a long time due to poor oil resistance, so that the performance is obviously reduced, and the service life and the operation reliability of the motor are seriously influenced.

The corona-resistant enameled wire is used as a main insulating material of the motor, and the performance of the corona-resistant enameled wire plays a decisive role in the service life of the motor and the like. The corona-resistant enameled wire used for the electric automobile motor in the market at present is mainly a 200-grade corona-resistant polyester imide/polyamide imide composite enameled wire, and the ATF oil resistance of the corona-resistant enameled wire is poor through tests, so that the corona-resistant enameled wire is gradually limited in application in the field of oil-cooled electric automobile motors. The technology of Japan is relatively advanced, and the corona-resistant polyamideimide single-coating enameled wire is researched and prepared, has good ATF oil resistance, and is widely applied to the oil-cooled motor field internationally, but the technology monopoly exists, and the corona-resistant polyamideimide single-coating enameled wire is expensive, so that the manufacturing cost of the corona-resistant enameled wire is very high, and after the ATF oil resistance test, the adhesive force and corona-resistant service life performance of a paint film are reduced by more than 80%, and the performance needs to be further improved and optimized.

CN105219233B discloses corona-resistant wire enamel and a preparation method thereof. The preparation method mainly comprises the steps of adding an inorganic oxide raw material into an organic solution, dispersing, grinding to obtain an inorganic oxide pre-dispersion liquid, adding a coupling agent into the inorganic oxide pre-dispersion liquid to form a corona-resistant modifier, and stirring the corona-resistant modifier and a paint body to prepare the corona-resistant wire enamel. The total solid content of the frequency conversion resistant wire enamel for the variable frequency motor prepared by the method is 41.97-43.8%, the viscosity is 320-. The corona-resistant wire enamel prepared by the invention has the advantages of high solid content, low viscosity, good corona resistance and long-term storage stability, can meet the requirements of a normal-temperature wire coating process, and is convenient to use and low in cost.

CN106675401A discloses corona-resistant wire enamel and a preparation method thereof. The corona-resistant wire enamel mainly comprises nano silicon dioxide, nano titanium dioxide, nano aluminum oxide, KH-560, nonylphenol polyoxyethylene ether, sulfonated polyetheramine-hyperbranched polypyrrolone copolymer, deionized water and N-methylpyrrolidone. The preparation method comprises the steps of mixing and stirring all the raw materials, and discharging to obtain the corona-resistant wire enamel. The prepared corona-resistant electromagnetic wire is subjected to performance test, the performance of a sample is found to be qualified after 30min at the temperature of 220 ℃ of hot impact, the corona resistance service life is 255h under the breakdown voltage of 48kV, and the corona resistance service life is 156h under the breakdown voltage of 30 kV. However, the raw materials used in the experiment have more components and the preparation process is complex.

CN106543890B provides a method for preparing corona-resistant polyamideimide wire enamel by chemical nano-doping. The preparation method mainly comprises the steps of firstly carrying out polycondensation on aluminum isopropoxide and methyltriethoxysilane to obtain a nano silicon/aluminum oxide dispersion liquid, then mixing N-methyl pyrrolidone, trimellitic anhydride and formic acid, then sequentially adding the nano silicon/aluminum oxide dispersion liquid, 4' -diphenylmethane diisocyanate, xylene and benzyl alcohol, heating and cooling, finally adding a mixed solvent of N-methyl pyrrolidone and xylene to adjust the solid content, and then adding a high-temperature curing catalyst to obtain the chemical nano doped corona-resistant wire enamel. The performance of a prepared sample is tested in an experiment, the chemical nano-doping method with the inorganic nano-doping amount of 20 wt.% is used for preparing the corona-resistant PAI wire enamel, the corona-resistant service life is 40h under the conditions of normal temperature, power frequency and electric field intensity of 60kV/mm, and is more than 20 times of that of the unmodified wire enamel. However, the wire enamel prepared by the method has short breakdown-resistant life and complex preparation process, and is not suitable for large-scale industrial production.

At present, corona-resistant wire enamel with excellent performance has good corona-resistant service life and larger storage stability, but is expensive, high in cost and not suitable for industrial production. Therefore, it is urgently needed to develop an enameled wire with low manufacturing cost, excellent ATF oil resistance and corona resistance to meet the technical requirements of development and application of an oil-cooled electric vehicle motor.

Disclosure of Invention

Aiming at the defects brought forward by the background technology, the invention provides an ATF oil-resistant corona-resistant enameled wire for an electric automobile motor and a preparation method thereof. The prepared corona-resistant enameled wire has excellent corona-resistant service life, easily obtained raw materials and low preparation cost.

In order to achieve the purpose, the invention adopts the following technical scheme:

the insulating layer is sequentially provided with an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating, an oil-resistant and corona-resistant protective coating, a corona-resistant polyamideimide coating and an oil-resistant and corona-resistant protective coating from inside to outside.

Further, the oil-resistant and corona-resistant protective coating, the corona-resistant polyamideimide coating and the oil-resistant and corona-resistant protective coating respectively account for 5-12% of the coating, 30-45% of the coating, 5-12% of the coating, 30-45% of the coating and 5-12% of the coating.

Further preferably, the 5 coating thickness ratios are 5-8%, 35-40%, 6-9%, 38-40% and 8-10%, respectively.

Further, the corona-resistant polyamideimide coating is formed by coating corona-resistant polyamideimide wire enamel prepared by modifying nano silicon dioxide and/or aluminum oxide, wherein the preparation method of the enamel comprises the following steps: adding 5-10% of nano powder with the total mass of 25-38% of the polyamide-imide paint liquid into the polyamide-imide paint liquid, and carrying out homogeneous dispersion for 1-2h (cooling by using cooling water, and controlling the material temperature to be less than or equal to 60 ℃) under the condition of 5000-; transferring the materials to a nano grinder for grinding and dispersing for 3-5h (cooling by using cooling water, controlling the temperature of the materials to be less than or equal to 60 ℃) until the D50 is less than or equal to 100nm, and performing high-pressure filtration by a filter bag with 3000 meshes to obtain the corona-resistant polyamide imide wire enamel.

Further, the nano powder is nano silicon dioxide and/or aluminum oxide, wherein the average grain diameter of the nano silicon dioxide and the average grain diameter of the aluminum oxide are 30-60 nm.

Further, the oil-resistant corona-resistant protective coating is formed by coating nano particle modified engineering plastic paint, wherein the preparation method of the paint comprises the following steps:

(1) adding a dispersing agent into N, N-dimethyl pyrrolidone for dispersion, then adding an inorganic filler for emulsification, and then cooling to obtain nano slurry;

(2) adding the nano slurry obtained in the step (1) into an engineering plastic solution, stirring, and then grinding to obtain a material 1;

(3) and (3) adding N, N-dimethyl pyrrolidone into the material 1 obtained in the step (2), and stirring to obtain the nano particle modified engineering plastic paint.

Further, the mass of the N, N-dimethyl pyrrolidone in the step (1) is 75-100 kg.

Further, the mass of the dispersant in the step (1) is 3-5 kg.

Further, the mass of the inorganic filler in the step (1) is 75-100 kg.

Further, the inorganic filler is added in the step (1) within 20-30 min.

Further preferably, the mass ratio of the N, N-dimethylpyrrolidone, the dispersant and the inorganic filler in the step (1) is 18-30:1: 20-28.

Further, the dispersant in the step (1) is one or more of BYK110, BYK163 and KH 560.

Further, the inorganic filler in the step (1) is nano silicon dioxide and/or aluminum oxide.

Further, the speed of the dispersion in the step (1) is 2000-25000r/min, and the time is 3-5 min.

Further, the speed of emulsification in the step (1) is 8000-9000r/min, and the emulsification time is 2-3 h.

Further, the cooling temperature in the step (1) is 50 ℃ or lower.

Further, the solid content of the nano slurry in the step (1) is controlled to be 40-50%.

Further, the mass of the nano slurry in the step (2) is 5-15 kg.

Further, the preparation method of the engineering plastic solution in the step (2) comprises the following steps: adding a certain amount of engineering plastic into N, N-dimethyl pyrrolidone (controlling the mass content of solid to be 30-40%) and stirring, wherein the mass ratio of the engineering plastic to the N, N-dimethyl pyrrolidone is 1:1.5-2.5, and the stirring speed is 500-1500r/min, stirring until the engineering plastic is uniformly dissolved, thereby obtaining the engineering plastic solution.

Further, the engineering plastic in the step (2) is one or more of polycarbonate, polyformaldehyde, polyphenylene sulfide, polyether sulfone and polyether ether ketone.

Further, the mass of the engineering plastic solution in the step (2) is 60-100 kg.

Further, the stirring speed in the step (2) is 500-.

Further, the milled particle size D50<100nm as described in step (2).

Further, the mass of the N, N-dimethyl pyrrolidone in the step (3) is 12-35 kg.

Further, the stirring temperature in the step (3) is 30-60 ℃ and the time is 1-2 h.

Further, the solid content of the nanoparticle modified engineering plastic paint in the step (3) is 25-35%.

The invention also provides a preparation method of the enameled wire, which comprises the following steps:

s1: paying off a copper conductor; s2: annealing at 490 deg.C/470 deg.C (490 deg.C for the first section of the inlet and 470 deg.C for the second section of the outlet) for 20-150 s; s3: painting by a mould method; s4: baking at 560 ℃ and 580 ℃ for 3-10 min; s5: cooling and monitoring on-line pinholes; s6: and (6) automatically collecting the disc.

Compared with the prior art, the invention has the beneficial effects that:

(1) the ATF oil resistance of the enameled wire prepared by the invention is obviously improved, and the performance index retention rate is more than 80% in a high-temperature and low-temperature cycle 8-cycle test of ATF oil.

(2) The corona resistance service life of the enameled wire prepared by the invention is excellent. According to the test of national standard, the corona-resistant service life of the secondary paint film corona-resistant enameled wire with the wire gauge of 0.8mm can be more than 100 h.

(3) The enameled wire prepared by the invention has good self-lubricating effect, can meet the requirement of high-slot-fullness stator coil inserting, avoids the friction damage of the enameled wire paint film, and has low preparation cost and easily obtained raw materials.

Drawings

FIG. 1 is a structural view of a wire, wherein 1-copper conductor; 2-oil-resistant corona-resistant protective coating; 3-corona resistant polyamideimide coating; 4-oil-resistant corona-resistant protective coating; 5-corona resistant polyamideimide coating; 6-oil-resistant corona-resistant protective coating.

Detailed Description

For a better understanding of the present invention, the present invention is further described in conjunction with the following specific examples, wherein the terminology used in the examples is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention. The raw materials used in the examples are all common commercial products, and therefore, the sources thereof are not particularly limited.