Permanent magnet synchronous motor rotor protection sleeve and preparation method thereof

Abstract

The application provides a permanent magnet synchronous motor rotor protection sleeve and a preparation method thereof. The method provided by the application is that carbon fibers are wound on a customized mold after being soaked in resin, and then the resin on the carbon fibers is crosslinked through solidification, so that a finished product is obtained, and then a special paint for sealing and coating insulation is applied to the finished product to prepare the rotor protection sleeve made of carbon fibers and resin material. The rotor protection sleeve made of this material has better heat resistance and thermal conductivity. The glue content of the rotor protection sleeve is controlled to be 25-35%, so that the rotor protection sleeve has better process performance, the finished product has better physical properties, and the magnetic field shielding effect of the carbon fiber material can be exerted; and the excellent performance can ensure the heat dissipation of the high-speed motor under long-time work and avoid the eddy current loss of the motor permanent magnet caused by the high-frequency magnetic field.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of motor parts preparation, and particularly relates to a permanent magnet synchronous motor rotor protection sleeve and a preparation method thereof. BACKGROUND

[0002] The alloy protection sleeve with high conductivity also generates a large amount of heat during the operation of the permanent magnet synchronous motor rotor, and therefore the rotor protection sleeve is required to have good heat conductivity. The carbon fiber material is a good conductor of heat and shields a high-frequency magnetic field, reducing the eddy current loss in the permanent magnet.

[0003] The existing carbon fiber rotor protection sleeve production process is a pipe winding process. The carbon fiber cloth is cut into the required size, wound on the mold layer by layer, and then prepared through curing, demolding, edge trimming and other processes. In the pipe winding process, the carbon fiber is not a whole, and the layers are disconnected. At high speed, the joint position is easy to separate, causing serious problems such as motor sweep, and leading to motor burnout. It is only suitable for producing low-speed (3000 rpm or less) motor rotor protection sleeves and cannot meet the requirements of high-speed motor performance. In high-end motors, especially in motor rotor protection sleeves with a rotor diameter of more than 100 mm and a speed of more than 20,000 rpm, a metal protection sleeve is generally used. The conventional method is to use a whole piece of metal material to process a whole piece of metal material, which has high processing cost and long cycle. SUMMARY

[0004] The application provides a permanent magnet synchronous motor rotor protection sleeve and a preparation method thereof, which can be used to prepare a rotor protection sleeve of a high-speed motor.

[0005] The preparation method of the permanent magnet synchronous motor rotor protection sleeve provided in the embodiment includes the following steps:

[0006] The first aspect of the application provides a preparation method of a permanent magnet synchronous motor rotor protection sleeve, including:

[0007] Step one, the carbon fiber wire is adjusted in tension by a tensioner, and is arranged in order and in line on the roller shaft by the roller shaft, and is soaked in resin;

[0008] Step two, the carbon fiber wire soaked in resin is wound on the mold by a winding machine to obtain a preform;

[0009] Step three, the preform on the mold is placed in a rotary curing oven for curing to obtain a rotor protection sleeve;

[0010] Step four, the rotor protection sleeve cured is demolded by using a demolding machine.

[0011] On this basis, the preparation method further comprises: step five, appearance finishing of the rotor protection sleeve after demolding; and sealing and insulation treatment of the surface of the finished rotor protection sleeve. The method can further protect the main structure of the rotor protection sleeve.

[0012] In an embodiment of the application, the resin in step one comprises any one of epoxy resin or modified epoxy resin. The epoxy resin or modified epoxy resin has better thermosetting and process performance, and the hardness and strength after curing are better matched with the carbon fiber filaments.

[0013] In an embodiment of the application, the viscosity of the epoxy resin is 1000-1500 mPa·s. Controlling the resin viscosity makes the carbon fiber filament gluing more smoothly, and has better process performance.

[0014] In an embodiment of the application, the winding method in step two is that the carbon fiber filaments are wound on the mold for n layers, n>2, and the number of winding layers is determined according to the thickness requirement of the actual product and the diameter of the carbon fiber filaments. The product thickness is generally 0.2-10 mm.

[0015] In an embodiment of the application, the included angle between the carbon fiber filaments and the axis of the mold is 15°-165°, and the direction intersection angle of every two layers of carbon fiber filaments is complementary.

[0016] In an embodiment of the application, the curing process in step three adopts gradient curing, and the temperature is 50-70℃ for 1-3 h of heat preservation and curing; the temperature is 80-110℃ for 1-3 h of heat preservation and curing; and the temperature is 160-180℃ for 40 min-80 min of heat preservation and curing. The curing process can ensure that the rotor protection sleeve is uniformly heated and chemically reacts, and the curing rate reaches 97%.

[0017] In an embodiment of the application, the environment humidity of the preparation method is 30-40%.

[0018] In an embodiment of the application, the environment temperature of the preparation method is controlled at 20-30℃. Maintaining a certain environment temperature and humidity can stabilize the viscosity of the resin system and ensure the glue content after the carbon fiber filaments are infiltrated.

[0019] Another aspect of the application provides a rotor protection sleeve prepared by the preparation method, and the rotor protection sleeve is used in a motor with a rotation speed of more than 3000 revolutions.

[0020] Compared with the prior art, the method provided by the application has the advantages and beneficial effects that: the method provided by the application is that carbon fibers are wound on a customized mold after being soaked in resin, the resin on the carbon fibers is crosslinked by curing, the finished product is sealed and coated with special paint for insulation, and a rotor protection sleeve made of carbon fiber and resin material is prepared. The rotor protection sleeve made of this material has better heat resistance and thermal conductivity. The glue content of the rotor protection sleeve of the application is controlled to be 25-35%, which has better process performance, the finished product has better physical properties, and the magnetic field shielding effect of the carbon fiber material can be exerted; the excellent performance can ensure the heat dissipation of the high-speed motor (3000 rpm and above) under long-time work and avoid the eddy current loss of the motor permanent magnet caused by the high-frequency magnetic field.

[0021] The carbon fiber filaments are tensioned and wound and then cured by resin, and the adhesion between the carbon fiber filaments in each layer is higher, so the rotor protection sleeve can also be made very thin. This method can be adapted to the production of rotor protection sleeves of various sizes by adjusting the size of the mold and the adjustment of the layup, and has strong universality.

[0022] The preparation method provided by the application is suitable for mass production, has high production efficiency, and the curing rate is above 97%, so the finished product after curing is not easy to deform at room temperature, and the product quality is stable. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 It is a process diagram of the preparation method of the rotor protection sleeve of the permanent magnet synchronous motor.

[0024] Figure 2 It is the influence of the ambient temperature on the infiltration performance of the carbon fiber filaments.

[0025] Table 1 is the parameter of the carbon fiber composite material.

[0026] Table 2 is the product strength detection. DETAILED DESCRIPTION

[0027] In order for those skilled in the art to better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0028] Example 1: Preparation method of rotor protection sleeve of permanent magnet synchronous motor

[0029] The preparation method of the rotor protection sleeve of the permanent magnet synchronous motor is shown in the process diagram as Figure 1 which includes the following steps:

[0030] Step one, carbon fiber yarn through tensioner adjust tension 40-150N, through the roller carbon fiber yarn according to the order neat unfolded arranged on the roller; arranged carbon fiber yarn soaked in resin; resin including epoxy resin, modified epoxy resin, etc. Different sources or kinds of resin viscosity has difference, therefore equipped with resin viscosity detector detects the viscosity of resin, generally the viscosity of resin is 1000-1500 mPa·s when the carbon fiber is soaked in the resin, the glue is uniform and stable.

[0031] Step two, carbon fiber yarn after soaking in resin through winding machine wound on the mold coated with release agent; obtain the preform;

[0032] The main components of the release agent are paraffin and silicone oil, and the release agent is evenly applied to the mold in one direction using cotton cloth; the amount is generally 5-20 grams according to the surface area of the mold;

[0033] In the present application, the winding machine winds the carbon fiber yarn on the mold according to a certain layering sequence. The carbon fiber yarn is wound on the mold for n layers, n>2, the number of layers is determined according to the thickness requirement of the actual product and the diameter of the carbon fiber yarn, and the product thickness is generally 0.2-10 mm. The included angle between the carbon fiber yarn and the axis of the mold is 15°-165° winding angle. The direction of every two layers of carbon fiber yarn is complementary, and the thickness of the wound preform is uniform.

[0034] Step three, the preform on the mold is put into a rotary curing oven for curing, and a rotor protection sleeve is obtained;

[0035] The curing process adopts gradient curing, the temperature is 55℃, the curing time is 1-3h; the temperature is 90℃, the curing time is 2h; the temperature is 180℃, the curing time is 40min-80min.

[0036] Step four, using the demolding machine to demold the cured rotor protection sleeve, and obtaining the rotor protection sleeve.

[0037] Step five, the rotor protection sleeve after demolding is finished; the lathe is used to determine the length and the short, so that the size of the finished product meets the requirements of the rotor protection sleeve; the surface treatment is carried out by grinding machine equipment, so that the smoothness is within ≤0.4. The surface of the finished rotor protection sleeve is sealed and insulated, and the present application adopts spraying flexible insulating paint. The paint is a special paint, which can prevent the fiber powder from falling off the surface of the rotor protection sleeve during the rotation of the rotor, avoid the conduction of the motor rotor and stator, and the motor sweep bore.

[0038] On the basis of the above preparation method, the resin viscosity is 1256 mPa·s, the number of winding layers is 12-18, the tension of carbon fiber yarn is 90N, the last 4 layers are 50N, the angle of odd layers is 75°, the angle of even layers is 105°, and 20 rotor protection sleeves with an inner diameter of 42mm, a length of 80mm and an outer diameter of 44.4-45.6mm are prepared.

[0039] After detection, the substandard products of insufficient curing were detected after curing, and the curing rate of all the rotor protective sleeves prepared reached 97%, preventing deformation after 3 days. Therefore, the curing effect is excellent. Therefore, the step-by-step curing can ensure that the rotor protective sleeve is uniformly heated and chemically reacted.

[0040] The appearance of the product is observed, the surface is smooth, there is no obvious lump, and it can be sealed and insulated after slight trimming and polishing.

[0041] Example 2: Influence of environmental temperature and humidity on product quality

[0042] Too high humidity will cause the fiber to be wet, and the moisture will block the fusion degree of the resin and the fiber. According to the actual process performance, the adhesion degree of the carbon fiber wire is generally controlled at 30-40% humidity.

[0043] The glue content of the carbon fiber after soaking is measured at an environmental humidity of 35%, and the results are shown in Table 2. Figure 1

[0044] According to the test results, it is shown that the higher the temperature, the lower the glue content, and the lower the temperature, the higher the glue content. According to the process requirements, when the glue content is controlled at 25-35%, the processing performance of the carbon fiber wire after impregnation is better, the appearance and performance requirements of the finished rotor protective sleeve are more excellent, and the finished product can play the magnetic field shielding effect of carbon fiber material. Therefore, the environmental temperature is controlled at 20-30℃.

[0045] Example 3: Performance of rotor protective sleeve

[0046] The rotor protective sleeve with an inner diameter of 42mm and a length of 80mm is designed, and the outer diameter is designed through simulation analysis.

[0047] 1. Simulation strength of rotor protective sleeve

[0048] The simulation conditions are as follows: rotor total amount 1.5kg', rotation speed 18,000r / min, and gap between stator and rotor 5mm.

[0049] The safety factor is set to 1.5 by software modeling. After the model is built, the simulation conditions and carbon fiber composite material parameters (Table 1) are input. When the model is running at 18,000r / min, the outer diameter size is increased one by one to see if it can meet the model requirements. The final result shows that the outer diameter size is 44.9mm. The number of layers of the process is 15, and the actual outer diameter is 45mm.

[0050] Table 1: Carbon fiber composite material parameters

[0051] Carbon fiber / epoxy material properties Units Longitudinal tensile modulus E θ ]] 120 GPa Transverse tensile modulus E r ]]> 8.8 GPa Shear modulus G θr = G θz ]]> 8.2 longitudinal GPa Shear modulus G rz ]] GPa Longitudinal-lateral Poisson ratio v θr = v θZ ]]> 0.31 -- Transverse-poisson ratio v rz ]]> -- Longitudinal tensile strength X 2100 MPa Longitudinal compression lightness X' 1200 MPa Transverse tensile strength Y 81.3 MPa Transverse compression lightness Y' MPa Density p 1.6-1.7 kg / m 3 ]]> Longitudinal thermal expansion coefficient 0.2 C^-1 Transverse thermal expansion coefficient 35 C^-1

[0052] ​2. Strength detection of finished rotor protection sleeve

[0053] The rotor protection sleeve prepared by the method of the present application is subjected to performance test according to GB / T 5349-2005, and the shear strength of the material of the product is tested, and the results are shown in Table 2.

[0054] Table 2: Strength detection of product

[0055] Product inner diameter*outer diameter*wall thickness / mm Tensile strength Tensile modulus Shear strength 42*45*80 2850 Mpa 650 Gpa 580 Mpa 55*58*70 mm 2760 Mpa 630 Gpa 550 Mpa

[0056] According to the test results in Table 2, it can be found that the rotor protection sleeve prepared by the preparation method of the present application has excellent strength. The carbon fiber material has excellent thermal conductivity and magnetic field effect, and the epoxy resin has stability at high temperature, combined with the high strength of the overall structure of the rotor protection sleeve, which can ensure that the rotor protection sleeve is not easily damaged under high-speed operation of the rotor.

[0057] After actual use test, the rotor protection sleeve of the present application is excellent not only for general low-speed motor (3000 revolutions or less), but also for high-speed motor of 3000 revolutions or more.

[0058] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, for those skilled in the art, the technical solutions recorded in the foregoing examples can still be modified, or some technical features can be replaced by equivalent; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions claimed by the present application.

Claims

1. A method for manufacturing a permanent magnet synchronous motor rotor protection sleeve, characterized in that, The method comprises the following steps: Step 1: Adjust the tension of the carbon fiber yarn to 40-150 N through a tensioner, and then arrange the carbon fiber yarn on the roller in order and soak the carbon fiber yarn in resin; Step 2: Wind the carbon fiber yarn soaked in resin on a customized mold through a winding machine, the number of winding layers n is greater than 2, and the winding angle of every two layers of carbon fiber yarn satisfies that the sum of the angles between the adjacent two layers of carbon fiber yarn and the mold axis is 180°; Step 3: Put the prefabricated product on the mold into a rotary curing furnace for curing by using a gradient curing process, specifically, curing at 50-70 ℃ for 1-3 h, curing at 80-110 ℃ for 1-3 h, and curing at 160-180 ℃ for 40-80 min; Step 4: Demold the rotor protection sleeve cured by using a demolding machine; Step 5: Perform appearance finishing on the demolded rotor protection sleeve, and spray insulating paint to seal and insulate the rotor protection sleeve.

2. The production method according to claim 1, characterized by, The resin in step 1 is epoxy resin or modified epoxy resin, and the viscosity is 1000-1500 mPa·s.

3. The preparation method according to claim 1, characterized in that The number of winding layers n in step 2 is determined according to the product thickness requirement and the diameter of the carbon fiber yarn, and the product thickness is 0.2-10 mm.

4. The method of claim 1, wherein, In the gradient curing process in step 3, the curing rate is greater than 97%.

5. The preparation method according to claim 1, characterized in that The environmental humidity of the preparation method is 30-40%, and the environmental temperature is 20-30 ℃.

6. A rotor jacket produced by the method of any one of claims 1 to 5, characterized in that The rotor protection sleeve is suitable for a permanent magnet synchronous motor with a rotating speed of greater than or equal to 3000 rpm.

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