A production method of 800V high-voltage corona-resistant enery drive motor enameled copper flat wire

Abstract

This invention discloses a method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors. The steps are: conductor annealing and plasma activation treatment, corner strengthening pre-coating, gradient dielectric constant insulation layer construction, multi-temperature zone hot air curing, surface lubrication layer coating, and finished wire winding. This application uses a pre-coating mold with guiding microgrooves for primary coarse adjustment, followed by a narrow-slit extrusion coating head for secondary fine adjustment, achieving targeted strengthening and thickening of the corner enamel film, effectively addressing the problem of concentrated electric fields at the corners under 800V high-voltage conditions. The inner layer with low εr (3.0) reduces the macroscopic electric field on the conductor surface, the outer layer with high εr (4.5) homogenizes the electric field distribution, and the middle corona-resistant functional layer provides the main protection. The three layers work together to make the electric field distribution of the insulation system more reasonable, improving PDIV and fully meeting the requirements of the 800V high-voltage environment. This invention has the advantage of meeting the requirements of the 800V high-voltage platform.

Description

Technical Field

[0001] This invention relates to the field of enameled wire technology, and in particular to a method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors. Background Technology

[0002] As new energy vehicles develop towards 800V high-voltage platforms, the insulation system of drive motor windings faces more stringent electrical stress challenges. The pulse voltage output by high-frequency inverters has a fast rise time (on the order of 100ns), which induces partial discharge in the flat-wire motor windings, leading to corona aging of the insulating varnish film.

[0003] In the prior art, the existing patent CN202111612403 discloses a flat enameled wire coating mold, which uses the rounded protrusions and recesses on the mold components to form an insulating film of uniform thickness around the flat wire by utilizing the surface tension and leveling principle of the paint liquid.

[0004] While this solution addresses the issue of thinning paint film at the four corners, it has the following drawbacks:

[0005] 1. Equal thickness design cannot cope with high voltage electric field concentration: Under an 800V high voltage platform, there is an electric field concentration effect at the four corners (R-angle) of a rectangular conductor, with an electric field concentration coefficient K. t It can reach 1.5 to 2.0. The uniform thickness of the paint film means that the electric field strength at the four corners is still significantly higher than that in the planar area. Partial discharge preferentially starts at the four corners. The uniform thickness design can only achieve passive defense and cannot actively homogenize the electric field.

[0006] 2. Design without considering dielectric constant gradient: The electric field distribution cannot be controlled by the insulating layer with a single dielectric constant. The local electric field enhancement coefficient β≈3~5 at the micro-protrusions on the conductor surface is much higher than the average field strength, which leads to PDIV limitation.

[0007] Therefore, there is an urgent need to develop an effective method for producing corona-resistant enameled copper flat wires for 800V high-voltage platforms. Summary of the Invention

[0008] The purpose of this invention is to provide a method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors. This invention has the advantage of meeting the requirements of an 800V high-voltage platform.

[0009] The technical solution of the present invention:

[0010] A method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors includes the following steps:

[0011] S1. Conductor Annealing and Plasma Activation Treatment: The copper flat wire conductor undergoes continuous annealing, followed by plasma activation treatment of the conductor surface. After plasma activation, the conductor proceeds directly to the coating process. The annealing temperature is 500℃~600℃, and the protective gas is nitrogen or a nitrogen-hydrogen mixture. The plasma activation treatment gas is a mixture of argon and oxygen, with a volume ratio of Ar:O2=4:1 and a power density of 0.5W / cm³. 2 ~2.0W / cm 2 The processing time is 10s to 30s, which forms a nanoscale pit rough structure with a depth of 50nm to 100nm on the surface of the conductor and introduces oxygen-containing active groups. The oxygen-containing active groups form hydrogen bonds / coordination bonds with the imide groups in the first layer of paint film that is subsequently coated, and generate a mechanical interlocking effect through the nano-pit rough structure, thereby improving the interfacial adhesion.

[0012] S2, Four-corner reinforcement pre-coating: A mold compensation-narrow slit extrusion combined pre-coating device is used to pre-coat the R-corner area of ​​the conductor with high dielectric constant corner filler paint. The pre-coating device adopts a two-stage synergy of coarse adjustment and fine adjustment. After pre-coating, it is preheated at 120℃~150℃ for 10s~20s by an online infrared preheating device to make the four-corner pre-coated paint film surface dry. The thickness of the four-corner pre-coated filler layer is 0.02mm~0.04mm, which is greater than the thickness of the adhesion layer in the planar area.

[0013] S3. Construction of gradient dielectric constant insulating layer: Three layers of gradient dielectric constant insulating layer are constructed sequentially on the conductor surface and the four corner pre-coating layers through a multi-pass mold coating process. During the coating process, the mold angle is flipped to ensure uniformity of the coating film. From the inside to the outside, they are low dielectric constant adhesion layer, corona resistant functional layer and high dielectric constant equalization layer.

[0014] S4. Multi-temperature zone hot air curing: Multi-temperature zone hot air curing is carried out through a vertical high-speed enameling oven, which is divided into four temperature control zones, each with independent hot air circulation speed control.

[0015] The first preheating zone has a temperature of 120℃~150℃, a hot air circulation speed of 8m / s~12m / s, and a residence time of 30s~60s per pass.

[0016] The second gelation zone has a temperature of 200℃~250℃, a hot air circulation speed of 10m / s~15m / s, and a residence time of 30s~60s per pass.

[0017] The third curing zone has a temperature of 350℃~380℃, a hot air circulation speed of 12m / s~18m / s, and a dwell time of 30s~60s per pass, which achieves synergistic cross-linking and curing of polyamide-imide, polyester-imide, and polyimide.

[0018] The fourth annealing zone has a temperature of 280℃~300℃, a hot air circulation velocity of 6m / s~10m / s, and a residence time of 30s~60s per pass.

[0019] S5. Surface lubrication layer coating: After the cured enameled wire is cooled to below 80°C by air cooling, a self-lubricating polyimide topcoat is coated on the outermost layer. The self-lubricating polyimide topcoat contains polytetrafluoroethylene micro powder with a particle size of 1μm to 5μm, a mass fraction of 3% to 5%, and a film thickness of 0.01mm to 0.02mm.

[0020] S6. Finished wire collection: Inspect the finished enameled wire and collect it.

[0021] In the aforementioned method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, the secondary synergy described in step S2 specifically refers to:

[0022] First-stage coarse adjustment - pre-coating mold: The inner cavity of the mold is provided with rounded protrusions in the corresponding four corner R-corner areas of the conductor. The curvature of the rounded protrusions is greater than the curvature of the conductor R-corner, and a first paint-receiving gap (gap height 50μm~100μm) is formed between the rounded protrusions and the conductor R-corner. The surface of the rounded protrusions is provided with guiding microgrooves, which use the surface tension of the paint liquid to guide the paint liquid to flow directionally from the center of the rounded protrusions to the edge, solving the fundamental problem of insufficient paint liquid supply in the four corner areas, so that the paint film thickness in the four corners reaches 80%~90% of the target value.

[0023] Secondary fine-tuning - narrow-slit extrusion corner coating head: Located 30cm to 50cm downstream of the pre-coating mold, it has four narrow-slit outlets corresponding to the four R-corners of the conductor. The narrow-slit width is 0.1mm to 0.3mm, and the distance between the narrow-slit outlet and the conductor surface is 0.05mm to 0.15mm. The distance is adjusted in real time by a servo motor (response time <0.5s) to compensate for the residual thickness fluctuation (±0.01mm) caused by the randomness of leveling in the pre-coating mold, and to precisely control the coating thickness at the four corners within the range of ±0.003mm of the target value.

[0024] In the aforementioned method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, the guide microgrooves have a groove width of 0.1mm to 0.3mm and a groove depth of 0.02mm to 0.05mm, and are distributed in a spiral or radial pattern.

[0025] The corner filler paint is a polyamide-imide-based paint containing barium titanate nanoparticles with a mass fraction of 15% to 20%, the barium titanate particle size is 20nm to 50nm, and the viscosity is 80mPa·s to 120mPa·s.

[0026] In the aforementioned production method of enameled copper flat wire for 800V high voltage corona resistant new energy drive motor, the corner filling paint further includes a dispersant, which is BYK-9076 or BYK-110, and the amount added is 2% to 5% of the mass of barium titanate.

[0027] In the aforementioned production method of enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, the online infrared preheating device is set between the pre-coating mold and the vertical high-speed enameling machine oven, and adopts far-infrared radiation heating with a wavelength of 2.5μm to 3.5μm, which matches the inherent absorption frequency of the resin material in the polyamide-imide paint; the power of the online infrared preheating device is adjusted in real time according to the feedback of the coating amount of the narrow-slit extrusion corner coating head, and the power is increased synchronously when the coating amount increases, to ensure consistent surface drying.

[0028] In the aforementioned method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, the three-layer gradient dielectric constant insulation layer mentioned in step S3 specifically refers to...

[0029] Low dielectric constant adhesion layer: Fluorine-modified polyamide-imide varnish, with a relative dielectric constant εr = 2.8~3.2 and a film thickness of 0.03mm~0.05mm, used to reduce the macroscopic electric field intensity on the conductor surface;

[0030] Corona-resistant functional layer: Polyesterimide paint modified with nano-silica and nano-alumina, with nano-silica particle size of 30nm~60nm and mass fraction of 8%~12%, nano-alumina particle size of 20nm~40nm and mass fraction of 3%~6%, relative permittivity εr=3.5~4.0, and paint film thickness of 0.08mm~0.12mm;

[0031] High dielectric constant equalization layer: polyimide varnish containing aluminum nitride nanoparticles and a mass fraction of 8%–12%, with aluminum nitride particle size of 50nm–100nm, relative dielectric constant εr = 4.2–4.8, and varnish film thickness of 0.04mm–0.06mm;

[0032] The dielectric constants of the three insulating layers satisfy a gradient increasing relationship: εr1 < εr2 < εr3, and the ratio of the thickness of each layer of the coating is d1:d2:d3 = 1:(2~2.5):(0.8~1.2).

[0033] In the aforementioned method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, the nano-silica and nano-alumina composite particles are surface-modified with a silane coupling agent before use. The silane coupling agent is γ-aminopropyltriethoxysilane or γ-glycidoxypropyltrimethoxysilane.

[0034] In the aforementioned production method of enameled copper flat wire for 800V high voltage corona resistant new energy drive motor, the total number of coating passes for the three-layer gradient dielectric constant insulation layer is 12 to 16, and the wet film thickness of each pass is 0.015mm to 0.025mm.

[0035] In the aforementioned production method of enameled copper flat wire for 800V high voltage corona resistant new energy drive motor, the total processing time of multi-temperature zone hot air curing in step S4 is 8 min to 12 min, of which the residence time in the third curing zone accounts for 40% to 50% of the total time.

[0036] Compared with the prior art, the beneficial effects of this application are as follows:

[0037] 1. The first-stage coarse adjustment is achieved through the pre-coated mold guide micro-groove, and the second-stage fine adjustment is achieved through the narrow-slit extrusion coating head, so as to achieve targeted reinforcement and thickening of the paint film at the four corners (the thickness is greater than that of the flat area), which effectively solves the problem of electric field concentration at the four corners under the 800V high voltage platform;

[0038] 2. The four corners are pre-coated with barium titanate nanoparticles (εr>100) to form local high dielectric constant regions, thereby achieving active electric field homogenization;

[0039] 3. The inner layer with low εr (3.0) reduces the macroscopic electric field on the conductor surface, the outer layer with high εr (4.5) homogenizes the electric field distribution, and the middle layer with corona resistance undertakes the main protection. The three layers work together to make the electric field distribution of the insulation system more reasonable, improve PDIV, and fully meet the requirements of 800V high voltage environment.

[0040] 4. Nano-silica provides resistance to corona erosion, while nano-alumina provides high thermal conductivity, which can quickly dissipate corona heat and prevent local overheating and carbonization. The synergy of the two improves the corona resistance life compared to single nanoparticles. Attached Figure Description

[0041] Figure 1 This is a flowchart of the production method of the present invention. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0043] Example 1.

[0044] A method for producing 800V high-voltage corona-resistant enameled copper flat wire for new energy drive motors, with specifications of 2.0mm × 4.0mm (narrow side × wide side, R angle 0.5mm) for 800V corona-resistant enameled copper flat wire, such as... Figure 1 As shown, the steps are as follows:

[0045] S1. Using TU1 oxygen-free copper rod, copper flat wire of the target size is obtained through continuous extrusion and multi-pass precision rolling; continuous annealing treatment is performed at a temperature of 550℃ under nitrogen-hydrogen mixed gas protection (H2 3%); subsequently, it enters the plasma treatment chamber with an Ar:O2 = 4:1 mixed gas and a power density of 1.0W / cm³. 2 After processing for 20 seconds, the surface water contact angle decreased from 85° to 25°, forming a nano-pit structure with a depth of about 60nm; after processing, it proceeds to the coating process.

[0046] S2. A mold compensation-narrow slot extrusion combined pre-coating device is adopted, specifically:

[0047] S2.1, First-level coarse adjustment - pre-coating mold: The inner cavity has rounded protrusions in the four corner R-corner areas. The curvature of the rounded protrusions is greater than the curvature of the conductor R-corner, forming the first paint-accepting gap (gap height 80μm); the surface of the rounded protrusions is provided with spiral guiding microgrooves (groove width 0.2mm, groove depth 0.03mm, pitch 1.0mm).

[0048] S2.2, Secondary Fine Adjustment - Narrow Slit Extrusion Corner Touch-up Head: Located 40cm downstream of the pre-coating mold, with a narrow slit width of 0.2mm and a distance of 0.1mm from the conductor surface. The servo motor adjusts in real time based on online eddy current thickness measurement feedback.

[0049] Corner filling paint: PAI paint containing 18wt% barium titanate nanoparticles (particle size 30nm, εr≈120) and dispersant BYK-9076 (3wt%) (viscosity 95mPa·s), with a coating speed of 12m / min;

[0050] Surface drying was performed using an online infrared preheating device (temperature 130℃, preheating time 15s), resulting in approximately 60% solvent evaporation and no cross-linking of the paint film.

[0051] The pre-coated filler layer at the four corners is 0.03 mm thick, and the adhesion layer on the flat area is 0.01 mm thick. The thickness at the four corners is three times that of the flat area.

[0052] S3. Multi-pass coating is performed using a vertical high-speed enameling machine, employing standard coating molds:

[0053] S3.1, First layer (low εr adhesion layer): Fluorine-containing PAI paint (εr=3.0, actual measurement), 4 passes, wet film thickness of 0.02mm per pass, baking temperature 220℃ / 40s (second stage gelation zone), total dry film thickness 0.03mm;

[0054] S3.2, Second layer (corona-resistant functional layer): Modified polyesterimide varnish composed of nano-SiO2 (particle size 40nm, content 10wt%) and nano-Al2O3 (particle size 30nm, content 5wt%) (εr=3.8, actual measurement), 8 coats, wet film thickness of 0.018mm per coat, baking temperature 360℃ / 45s (third curing zone), total dry film thickness 0.10mm;

[0055] S3.3, Third layer (high εr uniform pressure layer): PI paint containing 10wt% aluminum nitride nanoparticles (particle size 80nm) + dispersant (εr=4.5, actual measurement), 3 passes, wet film of 0.02mm per pass, baking temperature 360℃ / 50s (third curing zone), total dry film thickness 0.05mm;

[0056] S4. Multi-zone hot air curing via a vertical high-speed enameling oven, with four temperature control stages:

[0057] S4.1 First preheating zone: 120℃ / 10m / s, 40s per pass;

[0058] S4.2, Second gelation zone: 220℃ / 12m / s, 45s per pass;

[0059] S4.3, Third curing zone: 360℃ / 15m / s, 50s per pass (PAI / polyesterimide / PI synergistic curing);

[0060] S4.4, Fourth Annealing Zone: 290℃ / 8m / s, 40s per pass; Total processing time: 10min;

[0061] S5, air-cooled to below 80℃, surface coated with PTFE modified PI lubricating layer, 2 passes, total thickness 0.015mm;

[0062] S6. Finished wire winding: Inspect the continuity and thickness of the paint film. If qualified, the winding tension is controlled at 8% of the conductor breaking strength.

[0063] Sampling offline testing: PDIV=1850V (pulse voltage method, effective value), corona resistance life (155℃, ±1500V, 20kHz square wave) median 450h, thermal shock 240℃ / 1d pass, softening breakdown temperature 285℃.

[0064] Example 2. A method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors, which is the same as in Example 1, except that the enameled copper flat wire produced has a specification of 1.5mm × 3.0mm (R angle 0.4mm);

[0065] The specific process has been adjusted as follows:

[0066] In step S2, the guide microgroove has a depth of 0.025 mm, a barium titanate content of 16 wt%, and a pre-coating thickness of 0.025 mm.

[0067] In S3, the first layer has 3 passes (total thickness 0.035mm), the second layer has 7 passes (total thickness 0.09mm), and the third layer has 4 passes (total thickness 0.06mm); in S4, the curing temperature is reduced by 10℃.

[0068] Test results: Total film thickness 0.20mm, corner thickness 0.23mm, surface thickness 0.19mm, corner / surface thickness ratio 1.21, PDIV=1820V, median corona resistance life 420h, meeting the 800V platform requirements.

Claims

1. A production method of enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motor, characterized in that, Includes the following steps: S1. Conductor Annealing and Plasma Activation Treatment: The copper flat wire conductor undergoes continuous annealing, followed by plasma activation treatment of the conductor surface. After plasma activation, the conductor directly proceeds to the coating process. The annealing temperature is 500℃~600℃, and the protective gas is nitrogen or a nitrogen-hydrogen mixture. The plasma activation treatment uses a mixture of argon and oxygen, with a volume ratio of Ar:O2=4:1 and a power density of 0.5W / cm³. 2 ~2.0W / cm 2 Processing time: 10s to 30s; S2, Four-corner reinforcement pre-coating: A high dielectric constant corner filler paint is pre-coated in the R-corner area of ​​the four corners of the conductor using a pre-coating device. The pre-coating device adopts a two-stage synergy of coarse and fine adjustment. After pre-coating, the paint film is preheated at 120℃~150℃ for 10s~20s by an online infrared preheating device to make the four-corner pre-coated paint film surface dry. The thickness of the four-corner pre-coated filler layer is 0.02mm~0.04mm, which is greater than the thickness of the adhesion layer in the planar area. S3. Construction of gradient dielectric constant insulating layer: Three layers of gradient dielectric constant insulating layer are constructed sequentially on the conductor surface and the four corner pre-coating layers. During the coating process, the mold angle is flipped to ensure the uniformity of the coating film. From the inside to the outside, they are low dielectric constant adhesion layer, corona resistant functional layer and high dielectric constant equalization layer. S4. Multi-temperature zone hot air curing: Multi-temperature zone hot air curing is carried out through a vertical high-speed enameling oven, which is divided into four temperature control zones, each with independent hot air circulation speed control. The first preheating zone has a temperature of 120℃~150℃, a hot air circulation speed of 8m / s~12m / s, and a residence time of 30s~60s per pass. The second gelation zone has a temperature of 200℃~250℃, a hot air circulation speed of 10m / s~15m / s, and a residence time of 30s~60s per pass. The third curing zone has a temperature of 350℃~380℃, a hot air circulation speed of 12m / s~18m / s, and a residence time of 30s~60s per pass. The fourth annealing zone has a temperature of 280℃~300℃, a hot air circulation velocity of 6m / s~10m / s, and a residence time of 30s~60s per pass. S5. Surface lubrication layer coating: After the cured enameled wire is cooled to below 80°C by air cooling, a self-lubricating polyimide topcoat is coated on the outermost layer. The self-lubricating polyimide topcoat contains polytetrafluoroethylene micro powder with a particle size of 1μm to 5μm, a mass fraction of 3% to 5%, and a film thickness of 0.01mm to 0.02mm. S6. Finished wire collection: Inspect the finished enameled wire and collect it.

2. The method for producing enameled copper flat wire for an 800V high-voltage corona-resistant new energy drive motor according to claim 1, characterized in that, The secondary collaboration mentioned in step S2 specifically refers to: First-level coarse adjustment - pre-coating mold: The inner cavity of the mold is provided with rounded protrusions in the R-corner areas of the corresponding conductors. The curvature of the rounded protrusions is greater than the curvature of the conductor R-corner. A first paint-accepting gap is formed between the rounded protrusions and the conductor R-corner. The surface of the rounded protrusions is provided with guide microgrooves. Secondary fine-tuning - narrow-slit extrusion corner coating head: Located 30cm to 50cm downstream of the pre-coating mold, it has four narrow-slit outlets corresponding to the four R-corners of the conductor. The narrow-slit width is 0.1mm to 0.3mm, and the distance between the narrow-slit outlet and the conductor surface is 0.05mm to 0.15mm.

3. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 2, characterized in that: The flow-guiding microchannels have a width of 0.1mm to 0.3mm and a depth of 0.02mm to 0.05mm, and are distributed in a spiral or radial pattern. The corner filler paint is a polyamide-imide-based paint containing barium titanate nanoparticles with a mass fraction of 15% to 20%, the barium titanate particle size is 20nm to 50nm, and the viscosity is 80mPa·s to 120mPa·s.

4. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 3, characterized in that: The corner filler paint also contains a dispersant, which is BYK-9076 or BYK-110, and the amount added is 2% to 5% of the mass of barium titanate.

5. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 2, characterized in that: The online infrared preheating device is located between the pre-coating mold and the vertical high-speed enameling machine oven, and uses far-infrared radiation heating with a wavelength of 2.5μm to 3.5μm. The power of the online infrared preheating device is adjusted in real time according to the feedback of the coating amount of the narrow-slit extrusion corner coating head. When the coating amount increases, the power increases synchronously to ensure consistent surface drying.

6. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 1, characterized in that, The three-layer gradient dielectric constant insulating layer mentioned in step S3 is specifically as follows: Low dielectric constant adhesion layer: Fluorine-modified polyamide-imide varnish, with a relative dielectric constant εr = 2.8~3.2 and a film thickness of 0.03mm~0.05mm, used to reduce the macroscopic electric field intensity on the conductor surface; Corona-resistant functional layer: Polyesterimide paint modified with nano-silica and nano-alumina, with nano-silica particle size of 30nm~60nm and mass fraction of 8%~12%, nano-alumina particle size of 20nm~40nm and mass fraction of 3%~6%, relative permittivity εr=3.5~4.0, and paint film thickness of 0.08mm~0.12mm; High dielectric constant equalization layer: polyimide varnish containing aluminum nitride nanoparticles and a mass fraction of 8%–12%, with aluminum nitride particle size of 50nm–100nm, relative dielectric constant εr = 4.2–4.8, and varnish film thickness of 0.04mm–0.06mm; The dielectric constants of the three insulating layers satisfy a gradient increasing relationship: εr1 < εr2 < εr3, and the ratio of the thickness of each layer of the coating is d1:d2:d3 = 1:(2~2.5):(0.8~1.2).

7. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 6, characterized in that: The nano-silica and nano-alumina composite particles are surface-modified with a silane coupling agent before use. The silane coupling agent is γ-aminopropyltriethoxysilane or γ-glycidoxypropyltrimethoxysilane.

8. The method for producing enameled copper flat wire for an 800V high-voltage corona-resistant new energy drive motor according to claim 6, characterized in that: The total number of coating passes for the three-layer gradient dielectric constant insulating layer is 12 to 16, and the wet film thickness of each pass is 0.015 mm to 0.025 mm.

9. The method for producing enameled copper flat wire for 800V high-voltage corona-resistant new energy drive motors according to claim 1, characterized in that: The total processing time for multi-temperature zone hot air curing in step S4 is 8 min to 12 min, of which the dwell time in the third curing zone accounts for 40% to 50% of the total time.

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