Rotor insulation structure of high-rotating-speed oil-cooled motor

Abstract

The invention relates to the technical field of motors, in particular to a high-rotating-speed oil-cooled motor rotor insulation structure and a preparation method thereof.The high-rotating-speed oil-cooled motor rotor insulation structure comprises a sleeve, the sleeve is arranged on the side face of a winding, the sleeve is used for fixing the end of a leading-out wire of a rotor and leading out the leading-out wire, and the sleeve extends out of the rotor through a through hole formed in a hollow shaft; and the motor is connected with a rotary rectifier diode of the motor. According to the rotor insulation structure, under the working conditions of high temperature, high rotating speed, oil liquid soaking and scouring, insulation material falling objects of paint and binding wires are effectively reduced, the insulation material falling objects caused by sleeve cracking are avoided, the risk of oil way blocking and insulation faults are reduced, and the reliability of an oil-cooled motor is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric machines, in particular to a high-speed oil-cooled motor rotor insulation structure and a preparation method thereof. BACKGROUND

[0002] With the increase of power density and high speed of the aviation oil-cooled motor, the speed has reached more than 25000r / min, and the highest temperature of the winding end has reached 200℃. The oil-cooled motor is prone to cause the insulation materials such as insulation paint, binding tape and sleeve to block the oil path under the working conditions of high temperature, high speed, oil immersion and scouring. The lead sleeve is prone to cracking under the working condition of high-speed rotation, which causes insulation failure and affects the reliability of the oil-cooled motor.

[0003] The existing high-thermal-conductivity coil insulation structure includes an insulation structure slot, a magnetic slot wedge, a high-thermal-conductivity slot insulation, a high-thermal-conductivity insulation pad strip, a high-thermal-conductivity wave belt, a high-thermal-conductivity polyimide film, a high-thermal-conductivity mica tape and an electromagnetic wire. On the basis of not losing the insulation performance and mechanical performance, the thermal conductivity coefficient of each part is fully considered in the design of the high-thermal-conductivity insulation structure, the temperature rise, electrical insulation performance, mechanical performance and heat resistance of the linear motor are effectively reduced, the impregnated paint of the epoxy anhydride, organic silicon and polyester imine system has good compatibility, and the thermal conductivity coefficient of the motor insulation structure is fundamentally improved.

[0004] However, the existing technology has not studied the problem of the falling objects of the high-speed high-power-density oil-cooled motor.

[0005] Therefore, it is necessary to provide a high-speed oil-cooled motor rotor insulation structure to solve the above problems. SUMMARY

[0006] In view of the problem of the falling objects of the high-speed high-power-density oil-cooled motor in the prior art, the present application provides a high-speed oil-cooled motor rotor insulation structure to solve the existing problems.

[0007] The high-speed oil-cooled motor rotor insulation structure of the present application adopts the following technical scheme, comprising: A sleeve is arranged on the side surface of the winding, which is used for fixing the lead-out end of the rotor and leading out the lead-out wire. The sleeve extends to the outside of the rotor through the through hole arranged on the hollow shaft and is connected with the rotating rectifier diode of the motor.

[0008] The through hole of the hollow shaft is concentrically provided with a bushing, and the inner ring of the bushing is sleeved on the sleeve. The bushing is used for limiting the radial direction of the centrifugal effect of the sleeve when the rotor rotates.

[0009] The sleeve is made of a polyimide film material.

[0010] The further technical solution of the present application is that a section of the sleeve is fixed on the axial side of the winding through a binding belt.

[0011] The further technical solution of the present application is that the binding belt adopts long-fiber polyaramid fiber and is soaked through impregnation paint.

[0012] The further technical solution of the present application is that the impregnation paint is unsaturated polyester-imide resin impregnation paint or epoxy-modified unsaturated polyester solvent-free resin impregnation paint.

[0013] The further technical solution of the present application is that the electromagnetic wire of the rotor adopts polyimide or polyamide-imide material.

[0014] The further technical solution of the present application is that the wire-embedding slot of the rotor core is provided with a slot wedge, and the material of the slot wedge adopts polyamide-imide laminated glass cloth board, polyimide laminated board or double-maleimide laminated glass cloth board.

[0015] The further technical solution of the present application is that the wire-embedding slot of the rotor core is provided with slot insulation and interlayer insulation, and the materials of the slot insulation and the interlayer insulation both adopt polyaramid fiber paper, imine film polyaramid fiber paper composite material or polyimide film.

[0016] The beneficial effects of the present application are: The temperature resistance grade of the rotor insulation structure provided by the present application can reach 200 DEG C, which can meet the design requirements of the rotor with a rotation speed of 25000r / min or above, so that the rotor insulation structure can effectively reduce the falling of the insulation materials such as paint and binding wire under the working conditions of high temperature, high rotation speed, oil immersion and flushing, avoid the falling of the insulation materials caused by the cracking of the sleeve, reduce the risk of oil passage blockage and insulation failure, and improve the reliability of the oil-cooled motor. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0018] Figure 1 FIG. 1 is a general structure schematic diagram of an embodiment of a high-speed oil-cooled motor rotor insulation structure of the present application; Figure 2 FIG. 2 is a side view of the embodiment of the high-speed oil-cooled motor rotor insulation structure of the present application; Figure 1 FIG. 3 is an enlarged view of the part A in FIG. 2; Figure 3 FIG. 4 is a sectional view of the part B in FIG. 2; Figure 2 FIG. 5 is an enlarged view of the part C in FIG. 4; FIG. 6 is an enlarged view of the part D in FIG. 4;Figure 4 For Figure 2 the cross-sectional view at B-B; Figure 5 is the stress nephogram of the lead-out wire at 17000r / min in the embodiment of the present application; Figure 6 is the stress nephogram of the lead-out wire at 25000r / min in the embodiment of the present application.

[0019] In the figure: 1, sleeve; 2, binding wire; 3, iron core; 4, electromagnetic wire; 5, hoop; 6, bushing; 7, hollow shaft; 8, slot wedge; 9, slot insulation; 10, interlayer insulation. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0021] An embodiment of the high-speed oil-cooled motor rotor insulation structure of the present application, as shown in Figure 1 , comprises: a sleeve 1 arranged on the winding side, which is used for fixing the end of the lead-out wire of the rotor and guiding the lead-out wire out of the rotor, and the sleeve 1 extends to the outside of the rotor through the through hole arranged on the hollow shaft 7 and is connected with the rotating rectifier diode of the motor.

[0022] Exemplarily, as shown in Figure 2 and Figure 3 , in one specific embodiment, the bushing 6 is concentrically arranged in the through hole on the hollow shaft 7, and the inner ring of the bushing 6 is sleeved on the sleeve 1, and the bushing 6 is used for limiting the sleeve 1 in the radial direction when the rotor rotates, so as to effectively avoid the sleeve scratching, prevent the sleeve from cracking and falling off to generate the excess of the oil-cooled motor during the rotation of the rotor, and avoid the lead-out wire from being damaged to cause the short circuit of the motor.

[0023] Exemplarily, in one specific embodiment, the sleeve 1 is made of polyimide film material. It should be noted that, since the sleeve 1 in the rotor insulation structure bears a large stress when the rotor rotates, in the embodiment, the rotor lead-out wire model is established: the inner surface of the hollow shaft is fixed, and the rotor is respectively given a rotation speed of 17000r / min and 25000r / min; the simulation result at 17000r / min is shown in Figure 5 , and the maximum stress of the lead-out wire is 51.8MPa. The simulation result at 25000r / min is shown in Figure 6The maximum stress of the lead wire is 83.3 MPa. However, current standards and IEC standards for 200℃ temperature-resistant sleeves, such as silicone rubber or silicone resin sleeves, have poor resistance to aviation lubricating oil. Uncoated fiberglass hoses are prone to fiber shedding under the scouring of high-temperature oil, and they harden after being impregnated with insulating varnish, making them unsuitable for aviation oil-cooled motors. The tensile strength of PTFE tubing is typically (15~35) MPa, with a Φ3.6×0.2 PTFE sleeve having a tensile strength of 33.9 MPa. The tensile strength of PTFE tubing is typically (20~30) MPa, with a Φ3.6×0.2 PTFE sleeve having a tensile strength of 32.9 MPa. Furthermore, both PTFE and PTFE tubing exhibit high wear rates under high-speed friction, failing to meet the insulation requirements of the lead wires in the rotor insulation structure of high-speed oil-cooled motors. Polyimide film materials typically have a tensile strength of 100–130 MPa, but they are relatively rigid. However, by controlling the molecular chain orientation and internal defects after the film is made into a thin film, it can become strong and tough, withstanding repeated bending without breaking, while still meeting the strength requirements of the lead wire. In this embodiment, the sleeve is made of polyimide film material, which is formed by flat-rolling and thermally bonding polyimide film. The Φ3.6×0.2 polyimide sleeve, after being impregnated with unsaturated polyesterimide resin or epoxy-modified unsaturated polyester solvent-free resin, shows a fracture strength reduction rate of less than 15% in the oil resistance test (aging in 4050 aviation lubricating oil at 200°C for 96 hours) after impregnation with unsaturated polyesterimide resin or epoxy-modified unsaturated polyester solvent-free resin. The polyimide sleeve adopts a film winding structure, which can balance the flexibility and rigidity of the material. At the same time, the polyimide film has excellent wear resistance, and it can withstand the centrifugal force of the rotor rotation, the friction of the contact material, and the tangential force of the through hole during operation.

[0024] For example, in one specific embodiment, a section of the sleeve 1 is fixed to the axial side of the winding by a binding strap 2.

[0025] For example, in one specific embodiment, the binding strap 2 is made of long-fiber polyaramid fiber and is impregnated with an impregnating varnish. The impregnating varnish is either an unsaturated polyesterimide resin impregnating varnish or an epoxy-modified unsaturated polyester solvent-free resin impregnating varnish. It should be noted that the binding strap made of long-fiber polyaramid fiber has good compatibility with the impregnating varnish and aviation lubricating oil. The impregnating varnish can uniformly penetrate into the binding strap made of long-fiber polyaramid fiber material, resulting in a smooth surface. After impregnation with the unsaturated polyesterimide resin or epoxy-modified unsaturated polyester solvent-free resin impregnating varnish, the tensile strength increases by 0.84%. After impregnation with the unsaturated polyesterimide resin or epoxy-modified unsaturated polyester solvent-free resin, an oil resistance test (aging in 4050 aviation lubricating oil at 200°C for 96 hours) is conducted, and its tensile strength still reaches 230N. Both unsaturated polyesterimide resin and epoxy-modified unsaturated polyester solvent-free resin exhibit adhesive strength greater than 30N at 180℃, and their adhesive strength decreases by less than 30% after an oil resistance test (aging in 4050 aviation lubricating oil at 200℃ for 96 hours). These resins demonstrate excellent high-temperature adhesion and resistance to aviation lubricating oil. Furthermore, the use of an electrically heated dripping process avoids resin residue on non-impregnated areas, preventing flaking from oil-cooled motors.

[0026] For example, such as Figure 4 As shown, in one specific embodiment, the electromagnetic wire 4 of the rotor is made of polyimide or polyamide-imide material, with a temperature resistance rating of 220°C or higher; the winding slot of the rotor core 3 is provided with slot wedges 8, which are made of polyamide-imide laminated glass cloth, polyimide laminate, or bismaleimide laminated glass fiber cloth, with a temperature resistance rating of 180°C or higher. The winding slot of the rotor core 3 is provided with slot insulation 9 and interlayer insulation 10, both of which are made of polyaramid fiber paper, polyaramid fiber paper composite material, or polyimide film.

[0027] The present invention will be described below with reference to specific embodiments: Example 1 In this embodiment, the electromagnetic wire of the rotor insulation structure is made of polyimide electromagnetic wire, the slot wedge is made of polyimide laminated glass cloth board, the binding tape is made of long fiber polyaramid fiber material, the slot insulation is made of polyaramid fiber paper, the impregnation varnish is made of unsaturated polyesterimide resin material, and the sleeve is a flat-wound polyimide sleeve. The specific process is as follows: 1) An automatic winding machine is used to wind electromagnetic wire to obtain a coil assembly; 2) Place slot insulation polyaramid fiber paper in the core slot of the un-inserted rotor assembly; 3) The coil assembly is embedded in the slot. During the winding process, interlayer polyaramid fiber paper is placed as needed, slot wedges are inserted, and the slot is sealed. 4) Use binding tape to bind the winding ends of non-lead wire ends starting from any slot, and apply loctite 415 instant adhesive evenly to the binding wire ends.

[0028] 5) For winding leads that are not leads, use flat-wound polyimide sleeves. The sleeves should be wrapped from the root of the lead and then tied tightly with binding tape. The sleeves should be inserted into the winding end face, and the binding wire ends should be evenly coated with loctite 415 instant adhesive.

[0029] 6) Electric heating process: The rotor insulation structure is coated with unsaturated polyesterimide resin by motor hot dripping, thus obtaining the rotor insulation structure.

[0030] Example 2 In this embodiment, the electromagnetic wire of the rotor insulation structure is a polyamide-imide electromagnetic wire, the slot wedge is a bismaleimide laminated fiberglass cloth board, the binding tape is a long-fiber polyaramid fiber binding tape, the slot insulation uses an imide film polyaramid fiber paper composite material, the impregnation varnish uses an epoxy-modified unsaturated polyester solvent-free resin material, and the bushing is a flat-rolled polyimide bushing. The specific process is as follows: 1) An automatic winding machine is used to wind electromagnetic wire to obtain a coil assembly; 2) Slot insulation is placed in the core winding slot of the unwound rotor assembly; 3) The coil assembly is embedded in the slot. During the winding process, interlayer polyurethane film and polyaramid fiber paper are placed as needed, and slot wedges are inserted and the slot is sealed. 4) Use binding tape to bind the winding ends of non-lead wire ends starting from any slot, and apply loctite 415 instant adhesive evenly to the binding wire ends.

[0031] 5) For leads that are not at the lead-out end, insert the sleeve. The sleeve should be wrapped around the base of the lead-out and then tied tightly with a binding tape. The sleeve should be inserted into the end of the winding. Apply loctite 415 instant adhesive evenly to the end of the binding wire.

[0032] 6) Electric heating process: The rotor insulation structure is electrically heated and dripped with epoxy-modified unsaturated polyester solvent-free resin.

[0033] Example 3 In this embodiment, the electromagnetic wire in the rotor insulation structure is a polyimide electromagnetic wire, the slot wedge is a polyimide laminate, the binding tape is a long-fiber polyaramid fiber binding tape, the slot insulation is a polyimide film, the impregnating varnish is an unsaturated polyesterimide resin material, and the bushing is a flat-wound polyimide bushing. The specific process is as follows: 1) An automatic winding machine is used to wind electromagnetic wire to obtain a coil assembly; 2) Place polyaramid fiber paper in the core slot of the un-inserted rotor assembly; 3) The coil assembly is embedded in the slot. During the winding process, interlayer polyimide film is placed as needed, and slot wedges are inserted and the slot is sealed. 4) Use binding tape to bind the winding ends of non-lead wire ends starting from any slot, and apply loctite 415 instant adhesive evenly to the binding wire ends.

[0034] 5) Insert the non-lead-out end of the winding lead into the bushing. The bushing should be wrapped from the root of the lead, and then the bushing should be tightly tied with a binding tape. The bushing should be inserted into the end of the winding. Apply Loctite 415 instant adhesive evenly to the end of the binding wire.

[0035] 6) Electric heating process: The rotor insulation structure is electrically heated and dripped with unsaturated polyesterimide resin.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A rotor insulation structure for a high-speed oil-cooled motor, characterized in that, include: The bushing, which is located on the side of the winding, is used to fix the ends of the rotor leads and to lead them out. The bushing extends to the outside of the rotor through a through hole provided on the hollow shaft and is connected to the rotating rectifier diode of the motor.

2. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, A bushing is concentrically installed in the through hole on the hollow shaft. The inner ring of the bushing is fitted onto the sleeve. The bushing is used to limit the centrifugal force of the sleeve in the radial direction when the rotor rotates.

3. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, The sleeve is made of polyimide film material.

4. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, One end of the bushing is fixed to the axial side of the winding by a binding strap.

5. The high-speed oil-cooled motor rotor insulation structure according to claim 4, characterized in that, The binding straps are made of long-fiber polyaramid fibers and are impregnated with varnish.

6. The high-speed oil-cooled motor rotor insulation structure according to claim 5, characterized in that, The impregnation varnish is an unsaturated polyester imide resin impregnation varnish or an epoxy-modified unsaturated polyester solvent-free resin impregnation varnish.

7. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, The electromagnetic wires of the rotor are made of polyimide or polyamide-imide.

8. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, The rotor core has slot wedges in its winding slots. The slot wedges are made of polyamine-imide laminated glass cloth, polyimide laminate, or bismaleimide laminated glass fiber cloth.

9. The high-speed oil-cooled motor rotor insulation structure according to claim 1, characterized in that, The rotor core is equipped with slot insulation and interlayer insulation in the winding slots. The materials for both slot insulation and interlayer insulation are polyaramid fiber paper, polyaramid fiber paper composite material, or polyimide film.

10. A method for preparing a rotor insulation structure for a high-speed oil-cooled motor, characterized in that, include: A coil assembly is obtained by winding electromagnetic wire using an automatic winding machine; Place slot insulation inside the winding slot of the iron core; The coil assembly is embedded in the slotted insulated groove. During the winding process, interlayer insulation is placed as needed, and slot wedges are inserted and the groove is sealed. Use cable ties to bind the winding ends that are not leads, and apply loctite 415 instant adhesive evenly to the ends of the cable ties. Insert the lead wire into the sleeve, wrap the sleeve from the root of the lead wire, and then tie the sleeve tightly with a binding strap. The sleeve needs to be inserted into the winding end face. Apply loctite 415 instant adhesive evenly to the end of the binding wire. The rotor insulation structure is obtained by applying unsaturated polyesterimide resin to the rotor insulation structure using motor thermal dripping.

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