A method for insulating a magnetic component for a rail vehicle and the component after the insulating process

Abstract

The application belongs to the field of insulation treatment, and particularly relates to a kind of insulation treatment method of magnetic component for railway vehicle and component after insulation treatment.The insulation treatment method provided by the application comprises the following steps: a) using nanocomposite insulating paint as impregnating liquid, vacuum pressure impregnation process is used to treat the magnetic component for railway vehicle;B) the magnetic component after impregnation treatment of step a) is subjected to gelation treatment, and the impregnated paint forms a gel layer;C) the magnetic component after gelation treatment of step b) is subjected to curing treatment, an insulation layer is formed, and the magnetic component after insulation treatment is obtained.The treatment method of the application combines "vacuum pressure impregnation process", "nanocomposite insulating paint" and "fine control curing process curve", which can effectively improve the problem of insufficient permeability of insulating paint, and the insulation layer of the treated component has good insulation, thermal conductivity and mechanical strength.

Description

Technical Field

[0001] This invention belongs to the field of insulation treatment, and particularly relates to an insulation treatment method for magnetic components used in rail vehicles and the component after insulation treatment. Background Technology

[0002] Rail vehicles, especially high-speed trains, operate under extremely harsh and complex conditions for extended periods. Their core magnetic components—such as transformers and reactors—are subjected to continuous high voltage and high current surges, electrical stresses from high-frequency switching, and intense mechanical vibrations generated during vehicle operation. This demanding working environment places unprecedentedly high demands on the interlayer insulation reliability and overall insulation performance of magnetic components primarily constructed from laminated silicon steel sheets. Currently, traditional insulation treatment processes commonly used in the industry, including brushing, spraying, or atmospheric pressure impregnation, suffer from a series of significant technical defects and limitations in practical applications.

[0003] First, traditional methods suffer from severely insufficient penetration. Due to the extremely tight stacked structure of silicon steel sheets, conventional insulating varnish cannot completely penetrate every tiny gap and corner of each sheet using its own fluidity. This incomplete penetration easily leaves tiny air gaps or insufficiently wetted dry spots inside the stack. These defects, under the influence of a high-voltage electric field, can become the initiation source of partial discharge (also known as corona discharge). Continuous partial discharge will slowly but irreversibly corrode the surrounding insulating material, and long-term accumulation may eventually lead to insulation failure or even catastrophic electrical breakdown accidents.

[0004] Secondly, the overall performance achieved by traditional insulation treatments is poor. The organic polymer coating formed after the curing of conventional insulating varnish typically has poor thermal conductivity, which severely hinders the timely dissipation of heat generated by losses such as hysteresis and eddy currents in the iron core during operation. Heat accumulation leads to excessively high component temperatures, which not only degrade the magnetic properties of magnetic materials (e.g., increasing iron losses and reducing permeability) but also accelerate the aging process of insulating materials, thus significantly shortening the overall service life of components. Furthermore, the mechanical strength of these organic coatings is relatively limited. Under the continuous and intense mechanical vibration environment of the traction drive system, the coating is prone to fatigue and microcracks. These cracks further compromise the integrity of the insulation, providing pathways for moisture and contaminants to infiltrate, and may expand into larger insulation defects, creating a vicious cycle that seriously threatens the long-term safety and reliability of the rail vehicle traction system. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide an insulation treatment method for magnetic components for rail vehicles and an insulation-treated component. The treatment method provided by the present invention can effectively improve the problem of insufficient penetration of insulating varnish, and the insulation layer of the treated component has good insulation, thermal conductivity and mechanical strength.

[0006] This invention provides an insulation treatment method for magnetic components used in rail vehicles, comprising the following steps:

[0007] a) Using nano-composite insulating varnish as the impregnation liquid, magnetic components for rail vehicles are treated by vacuum pressure impregnation process;

[0008] In step a), the nanocomposite insulating varnish comprises: 55-65 wt% matrix resin, 12-19 wt% nanofiller, 5-10 wt% reactive diluent, 10-15 wt% curing agent, 0.3-0.5 wt% accelerator, 0.8-1.2 wt% dispersant, 0.3-0.5 wt% antioxidant, and 0.2-0.4 wt% defoamer; the nanofiller comprises nano-alumina modified with coupling agent, nano-silica modified with coupling agent, nano-boron nitride modified with coupling agent, and nano-silicon carbide modified with coupling agent.

[0009] b) Perform gelation treatment on the magnetic components that have completed the impregnation treatment in step a) to form a gel layer from the impregnated paint;

[0010] In step b), the gelation treatment is performed at a temperature of 80-90°C for 30-60 minutes.

[0011] c) The magnetic component that has undergone gelation treatment in step b) is cured to form an insulating layer, resulting in an insulating magnetic component.

[0012] In step c), the curing process sequentially includes a low-temperature curing stage, a medium-temperature curing stage, a high-temperature curing stage, and a cooling stage; the heating rate of the low-temperature curing stage is 3~5℃ / h, the final temperature is 110~130℃, and the holding time is 1~3h; the heating rate of the medium-temperature curing stage is 4~6℃ / h, the final temperature is 140~160℃, and the holding time is 3~5h; the heating rate of the high-temperature curing stage is 4~6℃ / h, the final temperature is 170~190℃, and the holding time is 6~8h; the cooling rate of the cooling stage is ≤8℃ / h.

[0013] Preferably, the magnetic components for rail vehicles are preheated before undergoing the vacuum pressure impregnation process.

[0014] The preheating process has a heating rate of 5~10℃ / h, a final heating temperature of 105~115℃, and a holding time of ≥4h.

[0015] Preferably, the matrix resin is methyltetrahydrophthalic anhydride modified E-51 epoxy resin.

[0016] Preferably, the particle size of the nanofiller is 20~100nm.

[0017] Preferably, the coupling agent used to modify the nano-alumina is KH-550 silane coupling agent; the particle size of the nano-alumina is 30~50nm.

[0018] Preferably, the content of the coupling agent-modified nano-alumina in the nanocomposite insulating varnish is 6-9 wt%.

[0019] Preferably, the coupling agent used to modify the nano-silica is KH-560 silane coupling agent; the particle size of the nano-silica is 20~40nm.

[0020] Preferably, the content of the coupling agent-modified nano-silica in the nanocomposite insulating varnish is 2-3 wt%.

[0021] Preferably, the coupling agent used to modify the nano-boron nitride is KH-570 silane coupling agent; the particle size of the nano-boron nitride is 50~80nm.

[0022] Preferably, the content of the coupling agent-modified nano-boron nitride in the nanocomposite insulating varnish is 3-5 wt%.

[0023] Preferably, the coupling agent used to modify the nano-silicon carbide is a titanate coupling agent; the particle size of the nano-silicon carbide is 40~60nm.

[0024] Preferably, the content of the coupling agent-modified nano-silicon carbide in the nanocomposite insulating varnish is 1~2wt%.

[0025] Preferably, the reactive diluent is a glycidyl ether type reactive diluent;

[0026] And / or, the curing agent is methylhexahydrophthalic anhydride;

[0027] And / or, the promoter is 2-ethyl-4-methylimidazole;

[0028] And / or, the dispersant is a polycarboxylate polymeric dispersant;

[0029] And / or, the antioxidant is a hindered phenolic antioxidant;

[0030] And / or, the defoamer is an organosilicon defoamer.

[0031] Preferably, the specific process of treating magnetic components for rail vehicles using the vacuum pressure impregnation process includes:

[0032] The magnetic components for rail vehicles are placed in the impregnation equipment, and then the impregnation equipment is evacuated. After that, the nano-composite insulating varnish is injected into the impregnation equipment. Once the varnish has completely submerged the magnetic components, the evacuation of the impregnation equipment is stopped. Then, inert gas is injected into the impregnation equipment to increase the air pressure inside the equipment for pressure impregnation.

[0033] Preferably, the vacuuming process before injecting the nanocomposite insulating varnish specifically includes:

[0034] First, pump to -0.04 to -0.06 MPa and maintain for 8 to 15 minutes, then continue pumping to -0.09 to -0.1 MPa and maintain for 30 to 60 minutes.

[0035] Preferably, the nanocomposite insulating varnish is defoamed before being injected into the impregnation equipment.

[0036] Preferably, the injection rate of the nanocomposite insulating varnish is ≤5L / min.

[0037] Preferably, the specific process of injecting inert gas and performing pressure-holding impregnation includes:

[0038] First, the pressure inside the impregnation equipment is increased to 0.25~0.35MPa by injecting inert gas and held for 15~30 minutes. Then, the pressure inside the impregnation equipment is further increased to 0.5~0.8MPa and held for more than 60 minutes.

[0039] Preferably, after the pressure-holding impregnation is completed, the impregnation equipment is depressurized; the depressurization rate is ≤0.1MPa / min.

[0040] This invention provides an insulated component, which is obtained by treating a magnetic component for rail vehicles with the insulation treatment method described above.

[0041] Compared with the prior art, the present invention provides an insulation treatment method for magnetic components of rail vehicles and the insulation-treated components. The insulation treatment method provided by the present invention includes the following steps: a) using a nano-composite insulating varnish as an impregnating liquid and employing a vacuum pressure impregnation process to treat the magnetic components of rail vehicles; in step a), the nano-composite insulating varnish comprises: 55-65 wt% matrix resin, 12-19 wt% nanofiller, 5-10 wt% reactive diluent, 10-15 wt% curing agent, 0.3-0.5 wt% accelerator, 0.8-1.2 wt% dispersant, 0.3-0.5 wt% antioxidant, and 0.2-0.4 wt% defoamer; the nanofiller comprises coupling agent-modified nano-alumina, coupling agent-modified nano-silica, coupling agent-modified nano-boron nitride, and coupling agent-modified nano-silicon carbide; b) subjecting the magnetic components treated in step a) to gelation treatment, causing the impregnated varnish to form... Step b) involves forming a gel layer; in step c), the gelation treatment temperature is 80~90℃ and the time is 30~60min; step c) involves curing the magnetic component that has undergone gelation treatment in step b) to form an insulating layer, thereby obtaining an insulating magnetic component; in step c), the curing treatment sequentially includes a low-temperature curing stage, a medium-temperature curing stage, a high-temperature curing stage, and a cooling stage; the heating rate in the low-temperature curing stage is 3~5℃ / h, the final temperature is 110~130℃, and the holding time is 1~3h; the heating rate in the medium-temperature curing stage is 4~6℃ / h, the final temperature is 140~160℃, and the holding time is 3~5h; the heating rate in the high-temperature curing stage is 4~6℃ / h, the final temperature is 170~190℃, and the holding time is 6~8h; the cooling rate in the cooling stage is ≤8℃ / h. The key to this invention's processing method lies in the combination of "vacuum pressure impregnation (VPI) process," "nanocomposite insulating varnish," and "precise control of the curing process curve." Specifically: by employing the VPI process, the permeability of the insulating varnish is significantly improved; by using a specifically formulated nanocomposite insulating varnish, especially with optimized design of the nanofillers added to the varnish, the insulation performance, thermal conductivity, and mechanical strength of the insulating layer formed after curing are significantly enhanced, thereby effectively improving the overall performance of magnetic components for rail vehicles; by precisely controlling the curing process curve, the resin matrix in the varnish can be fully cross-linked and cured, and the nanofillers can be uniformly distributed, further improving the overall performance of the insulating layer formed after curing. The processing method provided by this invention can significantly improve the dielectric strength, thermal conductivity, mechanical strength, and corona resistance of the insulating layer of magnetic components for rail vehicles, thereby greatly enhancing the reliability and lifespan of magnetic components for rail vehicles under harsh operating environments. Detailed Implementation

[0042] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] This invention provides an insulation treatment method for magnetic components used in rail vehicles, comprising the following steps:

[0044] a) Using nano-composite insulating varnish as the impregnation liquid, magnetic components for rail vehicles are treated by vacuum pressure impregnation process;

[0045] b) Perform gelation treatment on the magnetic components that have completed the impregnation treatment in step a) to form a gel layer from the impregnated paint;

[0046] In step b), the gelation treatment is performed at a temperature of 80-90°C for 30-60 minutes.

[0047] c) The magnetic component that has undergone gelation treatment in step b) is cured to form an insulating layer, resulting in an insulating magnetic component.

[0048] In the processing method provided by this invention, in step a), the magnetic component for rail vehicles is preferably preheated before undergoing vacuum pressure impregnation to remove moisture and low-molecular-weight volatiles from the component. The preheating rate is preferably 5-10℃ / h to avoid stress deformation due to excessive temperature difference; specifically, it can be 5℃ / h, 5.5℃ / h, 6℃ / h, 6.5℃ / h, 7℃ / h, 7.5℃ / h, 8℃ / h, 8.5℃ / h, 9℃ / h, 9.5℃ / h, or 10℃ / h. The final temperature of the preheating is preferably 105-115℃, specifically 105℃ or 106℃. The temperatures are 107℃, 108℃, 109℃, 110℃, 111℃, 112℃, 113℃, 114℃, or 115℃; the preheating treatment is preferably held for ≥4h to thoroughly remove moisture and low-molecular-weight volatiles from the inside of the component, more preferably 4~10h, specifically 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h, or 10h.

[0049] In the processing method provided by the present invention, in step a), the nanocomposite insulating varnish comprises: 55-65 wt% matrix resin, 12-19 wt% nanofiller, 5-10 wt% reactive diluent, 10-15 wt% curing agent, 0.3-0.5 wt% accelerator, 0.8-1.2 wt% dispersant, 0.3-0.5 wt% antioxidant, and 0.2-0.4 wt% defoamer.

[0050] In the processing method provided by this invention, the matrix resin in the nanocomposite insulating varnish is preferably methyltetrahydrophthalic anhydride-modified E-51 epoxy resin. Compared with conventional E-51 epoxy resin, methyltetrahydrophthalic anhydride-modified E-51 epoxy resin, by introducing methyltetrahydrophthalic anhydride modification, can improve the resin's high-temperature resistance (long-term service temperature up to 180℃) and crosslinking density, thus solving the problem of high-temperature aging and cracking of conventional E-51 epoxy resin.

[0051] In the processing method provided by the present invention, the content of the matrix resin in the nanocomposite insulating varnish can be specifically 55wt%, 56wt%, 57wt%, 58wt%, 59wt%, 60wt%, 61wt%, 62wt%, 63wt%, 64wt%, or 65wt%.

[0052] In the processing method provided by this invention, the nanocomposite insulating varnish contains nano-fillers including nano-alumina (Al2O3) modified with coupling agent, nano-silicon oxide (SiO2) modified with coupling agent, nano-boron nitride (h-BN) modified with coupling agent, and nano-silicon carbide (SiC) modified with coupling agent. Specifically, the modified nano-alumina is mainly used to maintain the core thermal conductivity pathway of the insulating layer; the modified nano-silicon oxide is mainly used to ensure the dielectric strength and corona resistance of the insulating layer; the modified nano-boron nitride is mainly used to further improve the thermal conductivity of the insulating layer and enhance its arc resistance; and the modified nano-silicon carbide is mainly used to synergistically improve the mechanical strength and temperature resistance of the insulating layer and inhibit high-temperature aging and cracking of the insulating layer.

[0053] In the processing method provided by the present invention, the particle size of the nanofiller in the nanocomposite insulating varnish is preferably 20~100nm, specifically 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm or 100nm.

[0054] In the processing method provided by the present invention, the coupling agent for modifying the nano-alumina in the nano-composite insulating varnish is preferably KH-550 silane coupling agent; the particle size of the nano-alumina is preferably 30~50nm, specifically 30nm, 35nm, 40nm, 45nm or 50nm.

[0055] In the processing method provided by the present invention, the content of the nano-alumina modified by the coupling agent in the nano-composite insulating varnish is preferably 6 to 9 wt%, specifically 6 wt%, 6.2 wt%, 6.5 wt%, 6.7 wt%, 7 wt%, 7.2 wt%, 7.5 wt%, 7.7 wt%, 8 wt%, 8.2 wt%, 8.5 wt%, 8.7 wt%, or 9 wt%.

[0056] In the processing method provided by the present invention, the coupling agent for modifying the nano-silica in the nano-composite insulating varnish is preferably KH-560 silane coupling agent; the particle size of the nano-silica is preferably 20~40nm, specifically 20nm, 25nm, 30nm, 35nm or 40nm.

[0057] In the processing method provided by the present invention, the content of the nano-silica modified by the coupling agent in the nano-composite insulating varnish is preferably 2~3wt%, specifically 2wt%, 2.1wt%, 2.2wt%, 2.3wt%, 2.4wt%, 2.5wt%, 2.6wt%, 2.7wt%, 2.8wt%, 2.9wt%, or 3wt%.

[0058] In the processing method provided by the present invention, the coupling agent for modifying the nano-boron nitride in the nano-composite insulating varnish is preferably KH-570 silane coupling agent; the particle size of the nano-boron nitride is preferably 50~80nm, specifically 50nm, 55nm, 60nm, 65nm, 70nm, 75nm or 80nm.

[0059] In the processing method provided by the present invention, the content of the nano-boron nitride modified by the coupling agent in the nano-composite insulating varnish is preferably 3 to 5 wt%, specifically 3 wt%, 3.2 wt%, 3.5 wt%, 3.7 wt%, 4 wt%, 4.2 wt%, 4.5 wt%, 4.7 wt%, or 5 wt%.

[0060] In the processing method provided by the present invention, the coupling agent for modifying the nano-silicon carbide in the nano-composite insulating varnish is a titanate coupling agent (NDZ-311); the particle size of the nano-silicon carbide is preferably 40~60nm, specifically 40nm, 45nm, 50nm, 55nm or 60nm.

[0061] In the processing method provided by the present invention, the content of the nano-silicon carbide modified by the coupling agent in the nano-composite insulating varnish is preferably 1~2wt%, specifically 1wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%, or 2wt%.

[0062] In the processing method provided by this invention, the reactive diluent in the nanocomposite insulating varnish is preferably a glycidyl ether type reactive diluent (AGE-600). Compared with conventional non-reactive diluents, glycidyl ether type reactive diluents can effectively reduce the viscosity of the system (viscosity ≤ 500 mPa・s at 25℃), are non-volatile, leave no residue, and significantly improve the permeability of the varnish.

[0063] In the processing method provided by the present invention, the content of the active diluent in the nanocomposite insulating varnish can specifically be 5wt%, 5.5wt%, 6wt%, 6.4wt%, 6.5wt%, 7wt%, 7.5wt%, 8wt%, 8.5wt%, 9wt%, 9.5wt%, or 10wt%.

[0064] In the processing method provided by this invention, the curing agent in the nanocomposite insulating varnish is preferably methyl hexahydrophthalic anhydride (MHHPA). The use of methyl hexahydrophthalic anhydride in combination with a specific accelerator, 2-ethyl-4-methylimidazole, can make the curing reaction milder and avoid insulation layer defects caused by localized exothermic reactions.

[0065] In the processing method provided by the present invention, the content of the curing agent in the nanocomposite insulating varnish can specifically be 10wt%, 10.5wt%, 11wt%, 11.5wt%, 12wt%, 12.5wt%, 13wt%, 13.5wt%, 14wt%, 14.5wt%, or 15wt%.

[0066] In the processing method provided by this invention, the accelerator in the nanocomposite insulating varnish is preferably 2-ethyl-4-methylimidazole (EMI-2,4). The use of 2-ethyl-4-methylimidazole in combination with a specific curing agent, methyl hexahydrophthalic anhydride, can make the curing reaction milder and avoid insulation layer defects caused by localized exothermic reactions.

[0067] In the processing method provided by the present invention, the content of the accelerator in the nanocomposite insulating varnish can specifically be 0.3wt%, 0.32wt%, 0.35wt%, 0.37wt%, 0.4wt%, 0.42wt%, 0.45wt%, 0.47wt%, or 0.5wt%.

[0068] In the processing method provided by this invention, the dispersant in the nanocomposite insulating varnish is preferably a polycarboxylate polymeric dispersant (BYK-110). Polycarboxylate polymeric dispersants can specifically solve the agglomeration problem of nanofillers, reducing the settling rate of the fillers in the resin by more than 90% and improving storage stability to more than 6 months.

[0069] In the processing method provided by the present invention, the content of the dispersant in the nanocomposite insulating varnish can specifically be 0.8wt%, 0.82wt%, 0.85wt%, 0.87wt%, 0.9wt%, 0.92wt%, 0.95wt%, 0.97wt%, 1wt%, 1.02wt%, 1.05wt%, 1.07wt%, 1.1wt%, 1.12wt%, 1.15wt%, 1.17wt%, or 1.2wt%.

[0070] In the processing method provided by this invention, the antioxidant in the nanocomposite insulating varnish is preferably a hindered phenolic antioxidant. Hindered phenolic antioxidants can effectively inhibit resin oxidative degradation at high temperatures, improving the long-term stability of the insulation layer and extending its service life compared to conventional antioxidants.

[0071] In the processing method provided by the present invention, the content of the antioxidant in the nanocomposite insulating varnish can specifically be 0.3wt%, 0.32wt%, 0.35wt%, 0.37wt%, 0.4wt%, 0.42wt%, 0.45wt%, 0.47wt%, or 0.5wt%.

[0072] In the processing method provided by this invention, the defoamer in the nanocomposite insulating varnish is preferably an organosilicon defoamer (BYK-055). Organosilicon defoamers have low surface tension, enabling them to quickly break down microbubbles generated during impregnation and preventing pinhole defects in the insulation layer.

[0073] In the processing method provided by the present invention, the content of the defoamer in the nanocomposite insulating varnish can specifically be 0.2wt%, 0.23wt%, 0.25wt%, 0.27wt%, 0.3wt%, 0.32wt%, 0.35wt%, 0.37wt%, or 0.4wt%.

[0074] In the processing method provided by the present invention, step a) of the vacuum pressure impregnation process for processing magnetic components for rail vehicles preferably includes: placing the magnetic components for rail vehicles in an impregnation device, then evacuating the impregnation device, then injecting nano-composite insulating varnish into the impregnation device, stopping the evacuation of the impregnation device after the varnish has completely submerged the magnetic components, and then injecting inert gas into the impregnation device to increase the gas pressure inside the device for pressure-maintaining impregnation.

[0075] In the processing method provided by the present invention, the main purpose of vacuuming before injecting the nanocomposite insulating varnish during the above-mentioned vacuum pressure impregnation process is to ensure that the air in the micropores of the magnetic components of the rail vehicle is completely expelled, thus clearing the channels for the penetration of the insulating varnish.

[0076] In the processing method provided by the present invention, the vacuuming process before injecting the nanocomposite insulating varnish during the above-mentioned vacuum pressure impregnation process preferably includes: first evacuating to -0.04~-0.06MPa, maintaining for 8~15min, and then continuing to evacuate to -0.09~-0.1MPa, maintaining for 30~60min. Specifically, the vacuum level can be initially evacuated to -0.04 MPa, -0.042 MPa, -0.045 MPa, -0.047 MPa, -0.05 MPa, -0.052 MPa, -0.055 MPa, -0.057 MPa, or -0.06 MPa; the holding time after evacuating to a vacuum level of -0.04 to -0.06 MPa can be 8 min, 8.5 min, 9 min, 9.5 min, 10 min, 10.5 min, 11 min, 11.5 min, 12 min, 12.5 min, 13 min, 13.5 min, 14 min, 14.5 min, or 15 min. The vacuum level can be further evacuated to -0.09MPa, -0.091MPa, -0.092MPa, -0.093MPa, -0.094MPa, -0.095MPa, -0.096MPa, -0.097MPa, -0.098MPa, -0.099MPa, or -0.1MPa; the holding time after the vacuum level is evacuated to -0.09~-0.1MPa can be 30min, 32min, 35min, 37min, 40min, 42min, 45min, 47min, 50min, 52min, 55min, 57min, or 60min.

[0077] In the processing method provided by the present invention, during the above-mentioned vacuum pressure impregnation process, the nanocomposite insulating varnish is preferably degassed before being injected into the impregnation equipment in order to avoid the presence of air bubbles affecting the penetration of the insulating varnish.

[0078] In the processing method provided by the present invention, during the above-mentioned vacuum pressure impregnation process, the injection rate of the nanocomposite insulating varnish is preferably ≤5L / min to avoid generating new bubbles, and more preferably 0.5~5L / min, specifically 0.5L / min, 1L / min, 1.5L / min, 2L / min, 2.5L / min, 3L / min, 3.5L / min, 4L / min, 4.5L / min or 5L / min.

[0079] In the processing method provided by the present invention, the specific process of injecting inert gas and performing pressure-holding impregnation during the above-mentioned vacuum pressure impregnation process preferably includes: first, increasing the gas pressure in the impregnation equipment to 0.25~0.35MPa by injecting inert gas and holding the pressure for 15~30min, and then further increasing the gas pressure in the impregnation equipment to 0.5~0.8MPa and holding the pressure for impregnation for more than 60min. The inert gas is preferably nitrogen; the gas pressure can be initially increased to 0.25 MPa, 0.26 MPa, 0.27 MPa, 0.28 MPa, 0.29 MPa, 0.3 MPa, 0.31 MPa, 0.32 MPa, 0.33 MPa, 0.34 MPa, or 0.35 MPa; the pressure holding time after reaching 0.25~0.35 MPa can be 15 min, 16 min, 17 min, 18 min, 19 min, 20 min, 21 min, 22 min, 23 min, 24 min, 25 min, 26 min, 27 min, 28 min, 29 min, or 30 min; The specific pressure after the one-step pressurization can be 0.5MPa, 0.52MPa, 0.55MPa, 0.57MPa, 0.6MPa, 0.62MPa, 0.65MPa, 0.67MPa, 0.7MPa, 0.72MPa, 0.75MPa, 0.77MPa, or 0.8MPa; the pressure holding and impregnation time after the pressure is increased to 0.5~0.8MPa is preferably 60~120min, specifically 60min, 65min, 70min, 75min, 80min, 85min, 90min, 95min, 100min, 105min, 110min, 115min, or 120min.

[0080] In the processing method provided by this invention, during the vacuum pressure impregnation process, after the pressure-holding impregnation is completed, the impregnation equipment is depressurized. The depressurization rate is preferably ≤0.1 MPa / min to prevent the paint from flowing back and being lost due to a sudden drop in pressure, more preferably 0.01~0.1 MPa / min, specifically 0.01 MPa / min, 0.02 MPa / min, 0.03 MPa / min, 0.04 MPa / min, 0.05 MPa / min, 0.06 MPa / min, 0.07 MPa / min, 0.08 MPa / min, 0.09 MPa / min, or 0.1 MPa / min.

[0081] In the processing method provided by the present invention, the main purpose of the gelation treatment in step b) is to form a non-sticky gel layer to prevent the insulating varnish from flowing away and to ensure the uniformity of the varnish film. The preferred temperature for the gelation treatment is 80~90℃, specifically 80℃, 81℃, 82℃, 83℃, 84℃, 85℃, 86℃, 87℃, 88℃, 89℃ or 80℃. The preferred time for the gelation treatment is 30~60min, specifically 30min, 32min, 35min, 37min, 40min, 42min, 45min, 47min, 50min, 52min, 55min, 57min or 60min.

[0082] In the processing method provided by the present invention, step c) includes, in sequence, a low-temperature curing stage, a medium-temperature curing stage, a high-temperature curing stage, and a cooling stage.

[0083] In the processing method provided by this invention, during the curing process described above, the low-temperature curing stage is mainly used to allow the solvent in the insulating varnish to evaporate slowly, avoiding the generation of bubbles; the heating rate of the low-temperature curing stage is preferably 3~5℃ / h, specifically 3℃ / h, 3.2℃ / h, 3.5℃ / h, 3.7℃ / h, 4℃ / h, 4.2℃ / h, 4.5℃ / h, 4.7℃ / h, or 5℃ / h; the final temperature of the low-temperature curing stage is preferably 110~130℃, specifically 110℃, 112℃, 115℃, 117℃, 120℃, 123℃, 125℃, 127℃, or 130℃; the holding time of the low-temperature curing stage is preferably 1~3h, specifically 1h, 1.5h, 2h, 2.5h, or 3h.

[0084] In the processing method provided by this invention, during the above-mentioned curing process, the medium-temperature curing stage is mainly used to promote the initial cross-linking of the resin and nanofillers, thereby improving the adhesion of the insulating layer. The heating rate of the medium-temperature curing stage is preferably 4~6℃ / h, specifically 4℃ / h, 4.2℃ / h, 4.5℃ / h, 4.7℃ / h, 5℃ / h, 5.2℃ / h, 5.5℃ / h, 5.7℃ / h, or 6℃ / h. The heating endpoint temperature of the medium-temperature curing stage is preferably 140~160℃, specifically 140℃, 142℃, 145℃, 147℃, 150℃, 152℃, 155℃, 157℃, or 160℃. The holding time of the medium-temperature curing stage is preferably 3~5h, specifically 3h, 3.5h, 4h, 4.5h, or 5h.

[0085] In the processing method provided by this invention, during the above-mentioned curing process, the high-temperature curing stage is mainly used to completely cross-link and cure the resin to form a dense composite insulation structure; the heating rate of the high-temperature curing stage is preferably 4~6℃ / h, specifically 4℃ / h, 4.2℃ / h, 4.5℃ / h, 4.7℃ / h, 5℃ / h, 5.2℃ / h, 5.5℃ / h, 5.7℃ / h or 6℃ / h; the heating endpoint temperature of the high-temperature curing stage is preferably 170~190℃, specifically 170℃, 172℃, 175℃, 177℃, 180℃, 182℃, 185℃, 187℃ or 190℃; the holding time of the high-temperature curing stage is preferably 6~8h, specifically 6h, 6.5h, 7h, 7.5h or 8h.

[0086] In the processing method provided by the present invention, during the above-mentioned curing process, the cooling rate of the cooling stage is preferably ≤8℃ / h to avoid cracking of the insulation layer, more preferably 0.5~8℃ / h, specifically 0.5℃ / h, 1℃ / h, 1.5℃ / h, 2℃ / h, 2.5℃ / h, 3℃ / h, 3.5℃ / h, 4℃ / h, 4.5℃ / h, 5℃ / h, 5.5℃ / h, 6℃ / h, 6.5℃ / h, 7℃ / h, 7.5℃ / h or 8℃ / h.

[0087] In the processing method provided by the present invention, in step c), the thickness of the insulating layer is preferably 0.2~0.5mm, specifically 0.2mm, 0.23mm, 0.25mm, 0.27mm, 0.3mm, 0.32mm, 0.35mm, 0.37mm, 0.4mm, 0.42mm, 0.45mm, 0.47mm or 0.5mm.

[0088] The present invention also provides an insulating component, which is obtained by treating a magnetic component for rail vehicles according to the insulating treatment method described above.

[0089] For clarity, the following examples will be used to provide a detailed description.

[0090] Example 1

[0091] An insulation treatment method for magnetic components used in rail vehicles includes the following steps:

[0092] (1) Preheating treatment:

[0093] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0094] (2) Vacuum pressure impregnation:

[0095] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0096] Table 1 Formulation of Nanocomposite Insulating Varnish in Example 1

[0097]

[0098] (3) Preliminary gelation:

[0099] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0100] (4) Staged thermosetting:

[0101] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0102] Table 2 Curing procedure table for Example 1

[0103]

[0104] Comparative Example 1

[0105] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the nanocomposite insulating varnish used does not contain modified nano-h-BN and modified nano-SiC, while the total amount of nanofillers added remains the same. The specific preparation steps are described below:

[0106] (1) Preheating treatment:

[0107] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0108] (2) Vacuum pressure impregnation:

[0109] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 3 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0110] Table 3 Formulation of Comparative Example 1 Nanocomposite Insulating Varnish

[0111]

[0112] (3) Preliminary gelation:

[0113] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0114] (4) Staged thermosetting:

[0115] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0116] Comparative Example 2

[0117] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the nanofiller added to the nanocomposite insulating varnish is modified nano-Al2O3, while the total amount of nanofiller added remains the same. The specific preparation steps are described below:

[0118] (1) Preheating treatment:

[0119] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0120] (2) Vacuum pressure impregnation:

[0121] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. First, the pressure is evacuated to -0.05 MPa and maintained for 10 minutes. Then, the pressure is further evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 4 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. In the first step, the pressure is increased from atmospheric pressure to 0.3 MPa and maintained for 20 minutes. In the second step, the pressure is increased to 0.6 MPa and maintained for 90 minutes to impregnate the components. The pressure difference is used to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0122] Table 4 Formulation of Comparative Example 2 Nanocomposite Insulating Varnish

[0123]

[0124] (3) Preliminary gelation:

[0125] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0126] (4) Staged thermosetting:

[0127] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0128] Comparative Example 3

[0129] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the nanofiller added to the nanocomposite insulating varnish is modified nano-SiO2, while the total amount of nanofiller added remains the same. The specific preparation steps are described below:

[0130] (1) Preheating treatment:

[0131] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0132] (2) Vacuum pressure impregnation:

[0133] After preheating, the components are quickly transferred into the impregnation tank. The tank door is closed, and the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nano-composite insulating varnish (see Table 5 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0134] Table 5 Formulation of Comparative Example 3-Nano Composite Insulating Varnish

[0135]

[0136] (3) Preliminary gelation:

[0137] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0138] (4) Staged thermosetting:

[0139] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0140] Comparative Example 4

[0141] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the nanofiller added to the nanocomposite insulating varnish is modified nano-h-BN, while the total amount of nanofiller added remains the same. The specific preparation steps are described below:

[0142] (1) Preheating treatment:

[0143] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0144] (2) Vacuum pressure impregnation:

[0145] After preheating, the components are quickly transferred into the impregnation tank. The tank door is closed, and the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely expelled, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 6 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0146] Table 6 Formulation of Comparative Example 4 Nanocomposite Insulating Varnish

[0147]

[0148] (3) Preliminary gelation:

[0149] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0150] (4) Staged thermosetting:

[0151] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0152] Comparative Example 5

[0153] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the nanofiller added to the nanocomposite insulating varnish is modified nano-SiC, while the total amount of nanofiller added remains the same. The specific preparation steps are described below:

[0154] (1) Preheating treatment:

[0155] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0156] (2) Vacuum pressure impregnation:

[0157] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 7 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0158] Table 7 Formulation of Comparative Example 5-Nano Composite Insulating Varnish

[0159]

[0160] (3) Preliminary gelation:

[0161] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0162] (4) Staged thermosetting:

[0163] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0164] Comparative Example 6

[0165] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that, after impregnation with paint, a gelation treatment is not performed; instead, heat curing is carried out directly. The specific preparation steps are described below:

[0166] (1) Preheating treatment:

[0167] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0168] (2) Vacuum pressure impregnation:

[0169] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0170] (3) Staged thermosetting:

[0171] The components that have completed the impregnation process are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), so that the insulating varnish is completely cross-linked and cured to form a 0.35 mm thick insulating layer.

[0172] Comparative Example 7

[0173] An insulation treatment method for magnetic components used in rail vehicles, differing from Example 1 only in that the thermosetting process is not staged. The specific preparation steps are described below:

[0174] (1) Preheating treatment:

[0175] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0176] (2) Vacuum pressure impregnation:

[0177] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0178] (3) Preliminary gelation:

[0179] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0180] (4) Thermosetting:

[0181] The gel-treated parts are transferred to a curing oven and heated from 85°C (the final gel temperature) to 180°C at a rate of 5°C / h, and held at that temperature for 13h. Then, the parts are cooled from 180°C to room temperature at a rate of 6°C / h to form a 0.35mm thick insulating layer.

[0182] Example 2

[0183] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in the content of each component in the nanocomposite insulating varnish. The specific preparation steps are described below:

[0184] (1) Preheating treatment:

[0185] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0186] (2) Vacuum pressure impregnation:

[0187] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. First, the pressure is evacuated to -0.05 MPa and maintained for 10 minutes. Then, the pressure is further evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 8 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes. The pressure difference is used to push the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0188] Table 8 Formulation of Nanocomposite Insulating Varnish in Example 2

[0189]

[0190] (3) Preliminary gelation:

[0191] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0192] (4) Staged thermosetting:

[0193] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0194] Example 3

[0195] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in the content of each component in the nanocomposite insulating varnish. The specific preparation steps are described below:

[0196] (1) Preheating treatment:

[0197] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0198] (2) Vacuum pressure impregnation:

[0199] After preheating, the components are quickly transferred into the impregnation tank. The tank door is closed, and the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 9 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0200] Table 9 Formulation of Nanocomposite Insulating Varnish in Example 3

[0201]

[0202] (3) Preliminary gelation:

[0203] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0204] (4) Staged thermosetting:

[0205] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0206] Example 4

[0207] An insulation treatment method for magnetic components used in rail vehicles, differing from Example 1 only in that the gelation treatment temperature is 80°C and the treatment time is 60 min. The specific preparation steps are described below:

[0208] (1) Preheating treatment:

[0209] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0210] (2) Vacuum pressure impregnation:

[0211] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0212] (3) Preliminary gelation:

[0213] The parts that have completed the impregnation treatment are transferred to a gel oven, the oven temperature is raised to 80°C and held for 60 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0214] (4) Staged thermosetting:

[0215] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0216] Example 5

[0217] An insulation treatment method for magnetic components used in rail vehicles, differing from Example 1 only in that the gelation treatment temperature is 90°C and the treatment time is 30 minutes. The specific preparation steps are described below:

[0218] (1) Preheating treatment:

[0219] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0220] (2) Vacuum pressure impregnation:

[0221] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0222] (3) Preliminary gelation:

[0223] The parts that have completed the impregnation treatment are transferred to a gel oven, the oven temperature is raised to 90°C and held for 30 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0224] (4) Staged thermosetting:

[0225] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0226] Example 6

[0227] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in the staged thermosetting curing process. The specific preparation steps are described below:

[0228] (1) Preheating treatment:

[0229] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0230] (2) Vacuum pressure impregnation:

[0231] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0232] (3) Preliminary gelation:

[0233] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0234] (4) Staged thermosetting:

[0235] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 10 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0236] Table 10 Curing procedure table for Example 6

[0237]

[0238] Example 7

[0239] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in the staged thermosetting curing process. The specific preparation steps are described below:

[0240] (1) Preheating treatment:

[0241] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 110℃, controlling the heating rate at 5℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 6 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0242] (2) Vacuum pressure impregnation:

[0243] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0244] (3) Preliminary gelation:

[0245] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0246] (4) Staged thermosetting:

[0247] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 11 for details of the curing process), so that the insulating varnish is completely cross-linked and cured to form a 0.35 mm thick insulating layer.

[0248] Table 11 Curing procedure table for Example 7

[0249]

[0250] Example 8

[0251] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the preheating treatment has a heating rate of 10℃ / h, an endpoint temperature of 105℃, and a holding time of 8h. The specific preparation steps are described below:

[0252] (1) Preheating treatment:

[0253] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 105℃, controlling the heating rate at 10℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 8 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0254] (2) Vacuum pressure impregnation:

[0255] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0256] (3) Preliminary gelation:

[0257] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0258] (4) Staged thermosetting:

[0259] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0260] Example 9

[0261] An insulation treatment method for magnetic components used in rail vehicles differs from Example 1 only in that the preheating treatment has a heating rate of 7°C / h, an endpoint temperature of 115°C, and a holding time of 4h. The specific preparation steps are described below:

[0262] (1) Preheating treatment:

[0263] Place the assembled magnetic components (silicon steel sheet laminated core) into an oven; gradually raise the oven temperature from room temperature to 115℃, controlling the heating rate at 7℃ / h to avoid stress deformation of the components due to excessive temperature difference; after reaching the target temperature, maintain the temperature for 4 hours to ensure that the moisture and low molecular weight volatiles inside the magnetic components completely escape.

[0264] (2) Vacuum pressure impregnation:

[0265] After preheating, the components are quickly transferred into the impregnation tank. After closing the tank door, the vacuum pump is started. The pressure is first evacuated to -0.05 MPa and maintained for 10 minutes, then evacuated to -0.095 MPa and maintained for 45 minutes to ensure that the air in the overlap of the silicon steel sheets and the micropores of the components is completely removed, clearing the channels for the penetration of the insulating varnish. While maintaining a vacuum of -0.095 MPa, the pre-deaerated nanocomposite insulating varnish (see Table 1 for the complete formula of the varnish) is slowly injected at a rate of 2 L / min to avoid generating new air bubbles. After ensuring that the varnish completely submerges the components, the vacuum is stopped. Subsequently, nitrogen pressure is applied to the impregnation tank in two steps. The first step is to increase the pressure from atmospheric pressure to 0.3 MPa and maintain the pressure for 20 minutes. The second step is to continue to increase the pressure to 0.6 MPa and maintain the pressure for 90 minutes, using the pressure difference to drive the varnish to penetrate into the micro-gaps of the magnetic components. After impregnation, the pressure is slowly released to atmospheric pressure (the pressure release rate is 0.05 MPa / min) to prevent the varnish from flowing back and being lost due to a sudden drop in pressure.

[0266] (3) Preliminary gelation:

[0267] The parts that have completed the impregnation treatment are transferred to a gel oven, where the temperature is raised to 85°C and held for 45 minutes to allow the paint to initially cross-link and form a non-sticky gel layer.

[0268] (4) Staged thermosetting:

[0269] The gel-treated components are transferred to a curing oven and subjected to a multi-stage curing process, including a low-temperature stage, a medium-temperature stage, a high-temperature stage, and a cooling stage (see Table 2 for details of the curing process), to fully cross-link and cure the insulating varnish, forming a 0.35 mm thick insulating layer.

[0270] Performance Evaluation

[0271] The performance of the components treated in Example 1 and Comparative Example 1 was tested according to the test standards for insulation performance of magnetic components of rail vehicles (IEC 60664-1, GB / T 1408.1), and the results are shown in Table 12:

[0272] Table 12 Performance Evaluation Results

[0273]

[0274] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for insulating magnetic components used in rail vehicles, characterized in that, Includes the following steps: a) Using nano-composite insulating varnish as the impregnation liquid, magnetic components for rail vehicles are treated by vacuum pressure impregnation process; In step a), the nanocomposite insulating varnish comprises: 55-65 wt% matrix resin, 12-19 wt% nanofiller, 5-10 wt% reactive diluent, 10-15 wt% curing agent, 0.3-0.5 wt% accelerator, 0.8-1.2 wt% dispersant, 0.3-0.5 wt% antioxidant, and 0.2-0.4 wt% defoamer; the nanofiller comprises nano-alumina modified with coupling agent, nano-silica modified with coupling agent, nano-boron nitride modified with coupling agent, and nano-silicon carbide modified with coupling agent. b) Perform gelation treatment on the magnetic components that have completed the impregnation treatment in step a) to form a gel layer from the impregnated paint; In step b), the gelation treatment is performed at a temperature of 80-90°C for 30-60 minutes. c) The magnetic component that has undergone gelation treatment in step b) is cured to form an insulating layer, resulting in an insulating magnetic component. In step c), the curing process sequentially includes a low-temperature curing stage, a medium-temperature curing stage, a high-temperature curing stage, and a cooling stage; the heating rate of the low-temperature curing stage is 3~5℃ / h, the final temperature is 110~130℃, and the holding time is 1~3h; the heating rate of the medium-temperature curing stage is 4~6℃ / h, the final temperature is 140~160℃, and the holding time is 3~5h; the heating rate of the high-temperature curing stage is 4~6℃ / h, the final temperature is 170~190℃, and the holding time is 6~8h; the cooling rate of the cooling stage is ≤8℃ / h.

2. The insulation treatment method according to claim 1, characterized in that, The magnetic components for rail vehicles undergo preheating treatment before being processed by vacuum pressure impregnation. The preheating process has a heating rate of 5~10℃ / h, a final heating temperature of 105~115℃, and a holding time of ≥4h.

3. The insulation treatment method according to claim 1, characterized in that, The matrix resin is methyltetrahydrophthalic anhydride modified E-51 epoxy resin.

4. The insulation treatment method according to claim 1, characterized in that, The particle size of the nanofiller is 20~100nm.

5. The insulation treatment method according to claim 1, characterized in that, The coupling agent used to modify the nano-alumina is KH-550 silane coupling agent; the particle size of the nano-alumina is 30~50nm.

6. The insulation treatment method according to claim 1, characterized in that, The content of the nano-alumina modified with coupling agent in the nano-composite insulating varnish is 6~9wt%.

7. The insulation treatment method according to claim 1, characterized in that, The coupling agent used to modify the nano-silica is KH-560 silane coupling agent; the particle size of the nano-silica is 20~40nm.

8. The insulation treatment method according to claim 1, characterized in that, The content of the nano-silica modified with coupling agent in the nanocomposite insulating varnish is 2-3 wt%.

9. The insulation treatment method according to claim 1, characterized in that, The coupling agent used to modify the nano-boron nitride is KH-570 silane coupling agent; the particle size of the nano-boron nitride is 50~80nm.

10. The insulation treatment method according to claim 1, characterized in that, The content of the nano-boron nitride modified with coupling agent in the nanocomposite insulating varnish is 3~5wt%.

11. The insulation treatment method according to claim 1, characterized in that, The coupling agent used to modify the nano-silicon carbide is a titanate coupling agent; the particle size of the nano-silicon carbide is 40~60nm.

12. The insulation treatment method according to claim 1, characterized in that, The content of the nano-silicon carbide modified with coupling agent in the nanocomposite insulating varnish is 1~2wt%.

13. The insulation treatment method according to claim 1, characterized in that, The reactive diluent is a glycidyl ether type reactive diluent; And / or, the curing agent is methylhexahydrophthalic anhydride; And / or, the promoter is 2-ethyl-4-methylimidazole; And / or, the dispersant is a polycarboxylate polymeric dispersant; And / or, the antioxidant is a hindered phenolic antioxidant; And / or, the defoamer is an organosilicon defoamer.

14. The insulation treatment method according to claim 1, characterized in that, The specific process for treating magnetic components for rail vehicles using the vacuum pressure impregnation process includes: The magnetic components for rail vehicles are placed in the impregnation equipment, and then the impregnation equipment is evacuated. After that, the nano-composite insulating varnish is injected into the impregnation equipment. Once the varnish has completely submerged the magnetic components, the evacuation of the impregnation equipment is stopped. Then, inert gas is injected into the impregnation equipment to increase the air pressure inside the equipment for pressure impregnation.

15. The insulation treatment method according to claim 14, characterized in that, The vacuuming process before injecting the nanocomposite insulating varnish specifically includes: First, pump to -0.04 to -0.06 MPa and maintain for 8 to 15 minutes, then continue pumping to -0.09 to -0.1 MPa and maintain for 30 to 60 minutes.

16. The insulation treatment method according to claim 14, characterized in that, The nanocomposite insulating varnish undergoes a defoaming treatment before being injected into the impregnation equipment.

17. The insulation treatment method according to claim 14, characterized in that, The injection rate of the nanocomposite insulating varnish is ≤5L / min.

18. The insulation treatment method according to claim 14, characterized in that, The specific processes of injecting inert gas and performing pressure-holding impregnation include: First, the pressure inside the impregnation equipment is increased to 0.25~0.35MPa by injecting inert gas and held for 15~30 minutes. Then, the pressure inside the impregnation equipment is further increased to 0.5~0.8MPa and held for more than 60 minutes.

19. The insulation treatment method according to claim 14, characterized in that, After the pressure-holding impregnation is completed, the impregnation equipment is depressurized; the depressurization rate is ≤0.1MPa / min.

20. A component after insulation treatment, characterized in that, It is obtained by treating the magnetic components of rail vehicles with the insulation treatment method described in any one of claims 1 to 19.

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