CN118041016A - Motor stator winding manufacturing method, motor stator winding and insulation test method - Google Patents

Abstract

The embodiment of the application provides a motor stator winding manufacturing method, a motor stator winding and an insulation test method, wherein the stator winding comprises a stator iron core and an armature winding, the armature winding is arranged into a ring shape by a stator bar, and the stator iron core is wound in the middle of the stator bar; the manufacturing method comprises the following steps: winding alkali-free glass fiber tapes impregnated with silicon carbide high-resistance paint around the periphery of the part of the stator bar outside the stator core; and winding an alkali-free glass fiber tape impregnated with graphite paint around the part of the stator bar in the cladding area of the stator core. The motor stator winding obtained by the motor stator winding manufacturing method provided by the embodiment of the application is placed in a vacuum environment, so that the corona voltage can be increased, the motor stator winding is not easy to generate corona discharge phenomenon under higher current frequency, the service life of the stator is prolonged, and the reliability of the motor is also improved.

Description

Motor stator winding manufacturing method, motor stator winding and insulation test method

Technical Field

The present application relates to motor insulation technology, and in particular, to a method for manufacturing a motor stator winding, and an insulation test method.

Background

The rotor of the motor generates high heat by friction with air in the high-speed rotation process, the motor structure is easy to damage, and the motor can be placed in a vacuum environment to solve the problem, so that the high heat generated by friction between the rotor and air is reduced. However, in a vacuum environment, corona discharge phenomenon can be generated on the surface of a wire rod of a motor stator, insulating materials on the surface of the stator are eroded, the aging process of the stator is accelerated, and the safe operation of the motor is seriously influenced.

In addition, for a high-speed motor, the current frequency of the motor stator winding can reach 500Hz-1kHz, and the corona initial voltage is more easily reached in a vacuum environment to generate insulation breakdown.

Disclosure of Invention

In order to solve one of the technical defects, an embodiment of the application provides a motor stator winding manufacturing method, a motor stator winding and an insulation test method.

According to a first aspect of an embodiment of the present application, there is provided a method for manufacturing a stator winding of an electric motor, the stator winding including a stator core and an armature winding, the armature winding being arranged in a ring shape by a stator bar, the stator core being wound around a middle portion of the stator bar; the manufacturing method comprises the following steps:

Winding alkali-free glass fiber tapes impregnated with silicon carbide high-resistance paint around the periphery of the part of the stator bar outside the stator core;

and winding an alkali-free glass fiber tape impregnated with graphite paint around the part of the stator bar in the cladding area of the stator core.

According to a second aspect of an embodiment of the present application, there is provided a motor stator winding comprising: the stator iron core and the armature winding are arranged into a ring shape by a stator bar, and the stator iron core is wound in the middle of the stator bar;

an alkali-free glass fiber tape impregnated with silicon carbide high-resistance paint is wound around the periphery of the part of the stator bar, which is positioned outside the stator core;

And an alkali-free glass fiber tape impregnated with graphite paint is wound around the periphery of the part of the stator bar, which is positioned in the cladding area of the stator core.

According to a third aspect of the embodiment of the present application, there is provided an insulation test system for performing insulation test on the stator winding of the above-mentioned motor, including: the device comprises an alternating current power supply, a transformer, a capacitive voltage divider and a vacuum test cabin; the alternating current power supply and the transformer are used for providing an excitation power supply for the motor stator winding to be tested; the capacitive divider is used to measure the operating voltage of the motor stator windings.

According to a fourth aspect of an embodiment of the present application, there is provided an insulation testing method for testing a stator winding of an electric motor using the insulation testing system as above, comprising:

Placing a motor stator winding in a vacuum test cabin;

regulating the air pressure in the vacuum test cabin to reach preset air pressure;

Adjusting the frequency of the alternating current power supply to reach a preset frequency;

And regulating the voltage of the alternating current power supply to gradually rise, and acquiring the current working voltage of the motor stator winding when the motor stator winding is determined to generate corona.

According to the technical scheme provided by the embodiment, an alkali-free glass fiber belt which is soaked in the silicon carbide high-resistance paint is wound around the periphery of the part of the stator bar, which is positioned outside the stator core; the stator winding of the motor, which is obtained by the manufacturing method, is placed in a vacuum environment, so that the corona voltage can be increased, the corona discharge phenomenon of the stator winding of the motor is not easy to occur under higher current frequency, the service life of the stator is prolonged, and the reliability of the motor is also improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute a limitation on the application. In the drawings:

Fig. 1 is a schematic view of a part of a stator winding of a motor according to a first embodiment of the present application;

Fig. 2 is a front view and a right side view of a part of a structure of a stator winding of a motor according to a first embodiment of the present application;

FIG. 3 is a schematic cross-sectional view of a stator winding of an electric machine according to a first embodiment of the present application;

FIG. 4 is a flow chart of a potting method according to a first embodiment of the present application;

FIG. 5 is a schematic diagram of an insulation testing system according to a first embodiment of the present application;

FIG. 6 is a flowchart of an insulation testing method according to a first embodiment of the present application;

FIG. 7 is a schematic diagram of test results without insulation treatment;

FIG. 8 is a schematic diagram of a test result in an insulation test method according to a first embodiment of the present application;

Fig. 9 is a cross-sectional view of a flywheel energy storage motor according to a second embodiment of the present application;

Fig. 10 is a partial cross-sectional view of a flywheel energy storage motor according to a second embodiment of the present application;

Fig. 11 is a partial cross-sectional view of a flywheel energy storage motor according to a second embodiment of the present application;

fig. 12 is a partial cross-sectional view of a flywheel energy storage motor according to a second embodiment of the present application;

Fig. 13 is a schematic structural diagram of a flow guide tube in a flywheel energy storage motor according to a second embodiment of the present application;

Fig. 14 is a top view of a rotor in a flywheel energy storage motor according to a second embodiment of the present application;

Fig. 15 is a schematic structural diagram of a flywheel energy storage system according to a second embodiment of the present application;

fig. 16 is a cross-sectional view of a flywheel motor rotor according to a third embodiment of the present application;

FIG. 17 is a cross-sectional view of another flywheel motor rotor according to a fourth embodiment of the present application;

fig. 18 is a schematic cross-sectional structure of a flywheel energy storage device according to a fifth embodiment of the present application;

fig. 19 is a schematic view of the internal structure of a vacuum pumping assembly according to a fifth embodiment of the present application.

Detailed Description

In order to make the technical solutions and advantages of the embodiments of the present application more apparent, the following detailed description of exemplary embodiments of the present application is provided in conjunction with the accompanying drawings, and it is apparent that the described embodiments are only some embodiments of the present application and not exhaustive of all embodiments. It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other.

Example 1

As shown in fig. 1 and 2, the present embodiment provides a motor stator winding 1 including a stator core 11 and an armature winding 12, the armature winding 12 being arranged in a ring shape by stator bars in order, the armature winding 12 being embedded in the stator core 11. The stator core 11 is wound around the middle of the stator bar, and both axial ends of the stator bar are located outside the stator core 11.

For the above-described motor stator winding 1, the present embodiment provides a manufacturing method including: and an alkali-free glass fiber tape impregnated with silicon carbide high-resistance paint is wound around the part of the stator bar outside the stator core 11, and the high-resistance band 13 is formed by utilizing the nonlinear resistance characteristic of the material. And winding an alkali-free glass fiber tape impregnated with graphite paint around the periphery of the part of the stator bar in the cladding region of the stator core 11 to form a low stop band 14, so as to prevent corona generation.

In the above scheme, the glass fiber ribbon can be wound around the periphery of the stator bar correspondingly, and then the wound stator bar is arranged into the stator winding; or the stator bars can be arranged into stator windings first and then the glass fiber strips are correspondingly wound.

The motor stator winding obtained by the manufacturing method is placed in a vacuum environment, so that the corona voltage can be increased, the motor stator winding is not easy to generate corona discharge phenomenon under higher current frequency, the service life of the stator is prolonged, and the reliability of the motor is also improved.

On the basis of the technical scheme, the iron-bearing asbestos belt is wound on the periphery of the part of the stator bar, which is positioned in the cladding area of the stator core. The iron-containing asbestos belt and the alkali-free glass fiber belt soaked in graphite paint can be alternately wound, and also can be wound in a lamination way.

As shown in fig. 3, for a high-power flywheel energy storage motor, the power frequency is approximately 500Hz-1khz, the air pressure level is approximately less than 100Pa, and the first semi-conductive self-adhesive tape 21, the insulating self-adhesive tape 22 and the second semi-conductive self-adhesive tape 23 can be further wound around the periphery of the stator bar around which the glass fiber tape is wound.

The solution can be adapted to the irregular geometric stepped end of the stator bar. First, the first semi-conductive self-adhesive tape 21 is wound at the uneven position of the stator bar, and is wound for one circle in a lap-winding mode for the uneven electric field of the uniform conductor, so as to prevent the uneven discharge phenomenon or corona phenomenon. Then, 2-3 layers of insulating self-adhesive tapes 22 are wound on the first semiconductor self-adhesive tape 21 in a lap-wrapping mode, and the insulating self-adhesive tapes 22 can be 10kV or 35kV insulating self-adhesive tapes, so that the main insulating function of the motor stator winding is realized. Finally, a layer of second semi-conductive self-adhesive tape 23 is wound outside the insulating self-adhesive tape 22 in a lap-wrapping mode and is used for shielding an external electric field and field intensity at uneven irregular positions, preventing corona from generating and achieving the effect of enhancing insulation.

In addition to the above, the enhanced insulation may be provided in the following manner: the armature full-epoxy resin encapsulation mode is adopted to insulate the stator winding, the encapsulating material is thermosetting flame-retardant casting epoxy resin, and specifically can be thermosetting flame-retardant casting epoxy resin with liquid latency and premixed filler, the weight ratio of the main agent to the curing agent is 10:7, and the armature full-epoxy resin encapsulation type heat-insulating stator winding has good electric strength and heat-conducting property, and can bear high-low temperature impact at-40 ℃ to 180 ℃ and high flame retardance.

A specific scheme is as follows: as shown in fig. 4, the motor housing and windings are first treated with a potting mold and then the stator windings are placed in a vacuum potting apparatus. And then mixing the main agent and the curing agent for 0.5-3 hours at room temperature under the air pressure with the vacuum degree of 50Pa-800Pa to obtain the mixed filler, and properly stirring in the mixing process. After stirring is completed, pouring the mixed filler into the stator winding in a vacuum environment, and sequentially controlling the filler speed in the pouring process to ensure uniform pouring and no irregular shape. Curing treatment is carried out after casting is finished, wherein the curing treatment is carried out for 4 hours under the environment of 80 ℃ and for 8 hours under the environment of 140 ℃; or cured for 4 hours at 80 ℃ and 10 hours at 130 ℃ to ensure temperature and time to complete the cure. After curing, the temperature is gradually reduced to room temperature.

The insulation strength of the motor stator winding can be effectively improved by adopting the encapsulating mode.

Based on the above-described scheme, the present embodiment further provides a motor stator winding 1, including: the stator core 11 and the armature winding 12, the armature winding 12 is arranged in a ring shape by a stator bar, and the stator core 11 is wound on the middle part of the stator bar. An alkali-free glass fiber tape impregnated with silicon carbide high-resistance paint is wound around the periphery of the part of the stator bar, which is positioned outside the stator core 11; and an alkali-free glass fiber tape impregnated with graphite paint is wound around the periphery of the part of the stator bar, which is positioned in the cladding region of the stator core 11.

Further, the part of the periphery of the stator bar, which is positioned in the cladding area of the stator core 11, is also wound with an iron-containing asbestos belt.

Further, the periphery of the stator bar is further wound with a first semiconducting self-adhesive tape 21, an insulating self-adhesive tape 22 and a second semiconducting self-adhesive tape 23 in sequence. The first and second semi-conductive self-adhesive strips 21, 23 may be of the same material or of different materials.

Reference is made to the above for a specific embodiment of the stator winding of an electric machine.

On the basis of the technical scheme, the embodiment also provides an insulation test system for insulation test of the motor stator winding.

As shown in fig. 5, the insulation test system includes: an alternating current power supply 3, a transformer 4, a capacitive voltage divider 5 and a vacuum test chamber 6. The vacuum test cabin 6 can provide air pressure of 10Pa-101kPa for accommodating the test piece 9, and the vacuum test cabin 6 is also provided with an observation window, so that corona conditions in the vacuum test cabin 6 with darker light can be observed conveniently. The components are correspondingly and electrically connected, and the electronic wire rod can be used as a test piece 9 to be placed in the vacuum test chamber 6.

The outer wall of the vacuum test cabin 6 is provided with a cabin penetrating flange 7, and the connecting cable penetrates into the vacuum test cabin 6 through the cabin penetrating flange 7 to be connected with the test piece 9. The alternating current power supply 3 is specifically a controllable alternating current power supply, the alternating current power supply 3 and the transformer 4 are used for providing an excitation power supply for a test piece 9 to be tested, the capacitive voltage divider 5 is used for measuring the working voltage of the test piece 9, and high-frequency high-voltage excitation of 10kV/500Hz can be realized at maximum and is continuously adjustable, so that corona initial voltages under different air pressures and different frequencies can be measured, and the insulation strength of a motor stator winding is determined.

As shown in fig. 6, on the basis of the above technical solution, this embodiment further provides an insulation testing method for testing a stator winding of a motor by using the insulation testing system, including:

First, the stator bar is placed in the vacuum test chamber 6 and connected to the cable. The air pressure in the vacuum test chamber 6 is then adjusted to a preset air pressure, for example, 20Pa, 50Pa, 100Pa, 200Pa, 500Pa, 1kPa, 5kPa, 10kPa, 101kPa, or the like. The frequency of the ac power source 3 is adjusted to a preset frequency, which may be 50Hz, 250Hz, 500Hz or others.

Then, the voltage of the ac power supply 3 is adjusted to gradually rise from 0V, and the current stator bar operating voltage is obtained as the corona onset voltage when it is determined that the stator bar is corona-generating.

A specific scheme is as follows: during the adjustment of the voltage of the ac power supply 3 to gradually rise from 0V, it was observed whether corona occurred in the stator bar. After a set of tests was completed, the frequency of the ac power source 3 was adjusted, and then the voltage of the ac power source 3 was readjusted to gradually increase from 0V, and continued observation as to whether corona was generated. Thus, corona onset voltages at different pressures and different frequencies can be obtained.

Fig. 7 shows the corona test results without insulation treatment: test data show that after the air pressure is reduced to 1kPa, the corona onset voltage is reduced sharply with the air pressure, at 500Pa the corona onset voltage of the bare stator bar has been reduced to 0.62kV, at 200Pa to 0.51kV, and at 20Pa to a minimum of 0.36kV.

Fig. 9 shows the corona test results using the protocol provided in this example: the test data show that the corona onset voltage of the stator bar was re-measured at 50Hz and 500Hz voltages, respectively, where 4kV indicates that no corona occurred at 4 kV.

After insulation treatment, the corona initial voltage excited by 500Hz in a 500Pa environment is increased to 1.58kV, and the corona initial voltage is reduced along with the increase of the electric frequency, so that the corona initial voltage of the stator bar at 250Hz can be considered to be effectively increased to more than 1.58kV, and the insulation treatment can effectively increase the corona initial voltage in a vacuum environment.

Example two

As shown in fig. 9, this embodiment provides a flywheel energy storage motor, including: the housing 4 and the rotor 1.2 and the stator 3 arranged in the housing 4. The stator 3 is fixed in the casing 4, the rotor 1.2 is rotatably disposed in the casing 4 and located in an area surrounded by the stator 3, one end of the rotor 1.2 is connected with the flywheel 1.1 (i.e. the flywheel body 1 in fig. 1), and the rotor 1.2 and the flywheel 1.1 synchronously rotate along the same axis. A magnetic steel 2 is arranged between the rotor 1.2 and the stator 3. The stator 3 may employ the above-described scheme.

The other end of the rotor 1.2 (i.e. the end facing away from the flywheel 1.1) is provided with a heating element 6, and the heating element 6 is fixedly connected with the rotor 1.2. The inner surface of the shell 4 is provided with a receiving body 7, the surface of the receiving body 7 is opposite to the surface of the heating body 6, and the heating body 6 absorbs the heat of the rotor 1.2 and conducts the heat to the receiving body 7 so as to accelerate the heat dissipation of the rotor.

A cooling flow passage 42 for accommodating a cooling liquid is provided in the housing 4 at a position where the receiver 7 is provided. The cooling flow passage 42 is connected to a liquid cooling device, which supplies cooling liquid to the cooling flow passage 42, and the cooling liquid can absorb heat of the receiver 7, thereby further accelerating heat dissipation to the rotor.

According to the technical scheme, the heating body is arranged at the end part of the rotor, the receiving body is correspondingly arranged on the inner surface of the shell, heat of the rotor can be conducted to the receiving body through the arrangement of the heating body and the surface of the receiving body, and the heat is quickly dissipated through cooling liquid in the cooling flow channel in the shell, so that the radiating speed of the rotor is improved, the temperature rise of the rotor is reduced, the magnetic steel temperature is prevented from being too high, and the reliability of the flywheel energy storage motor is improved.

On the basis of the above-described aspects, as shown in fig. 9 and 10, at least two heat generating fins 61 are provided on the heat generating body 6, and at least two receiving fins 71 are provided on the receiving body 7. The heat generating fins 61 and the receiving fins 71 are alternately arranged, and the surfaces of the heat generating fins 61 and the surfaces of the receiving fins 71 are arranged opposite to each other, so that the heat exchange area is increased, the heat conduction speed is increased, and the heat dissipation of the rotor can be further accelerated.

A specific scheme is as follows: two heat fins 61 are provided, three receiving fins 71 are provided, and one heat fin 61 is provided between two adjacent receiving fins 71. So that both sides of the heat fin 61 can conduct heat rapidly.

The surfaces of the heat generating fins 61, the receiving fins 71 may be coated with a high emissivity coating to increase the surface emissivity thereof. The gap between the heat generating fins and the receiving fins 71 is greater than the motor air gap length.

As shown in fig. 9 and 11, in addition to the above technical solution, a heat pipe mounting hole 12 extending in the axial direction of the rotor is provided in the end surface of the rotor 1.2 where the heating element is provided, and the heat pipe 5 is inserted into the heat pipe mounting hole 12. The heat pipe 5 can be made of a material with good heat conduction performance, and can conduct heat of the rotor rapidly to realize heat dissipation.

Further, the heat pipe 5 is fixedly adhered in the heat pipe mounting hole 12 by heat conducting glue, and the heat conducting glue can improve heat conducting capability.

Further, the heat pipe 5 is internally provided with a phase change heat conducting material, the phase change heat conducting material is used for converting between liquid and gas, the heat conducting speed is greatly improved, the heat of the rotor is rapidly conducted to the end part, and the heat is dissipated through the heating body and the receiving body. The lower end of the heat pipe 5 is an evaporation end, and the phase-change heat-conducting material absorbs the heat of the rotor and is converted into a gaseous state; the upper end of the heat pipe 5 is a condensation end, and the heat of the phase-change heat-conducting material is released and then converted into a liquid state.

One embodiment is that: the number of the heat pipe installation holes 12 is plural, and the heat pipe installation holes are uniformly distributed along the circumferential direction of the rotor 1.2.

As shown in fig. 12, in the above-described embodiment, a nozzle mounting hole 11 extending in the axial direction of the rotor is provided in the middle of the end surface of the rotor 1.2 where the heating element 6 is provided. The honeycomb duct 8 is inserted in the honeycomb duct mounting hole 11, is equipped with the feed liquor passageway in the honeycomb duct 8, and the outer wall of honeycomb duct 8 is equipped with out the cistern. In addition, a rotary connector 9 is further arranged in the casing 4, a liquid supply channel of the rotary connector 9 is communicated with a liquid inlet channel of the flow guide pipe 8, and a return channel of the rotary connector 9 is communicated with a liquid outlet groove of the flow guide pipe 8.

The rotary connector 9 provides cooling liquid for the liquid inlet channel of the flow guide pipe 8, the cooling liquid reaches the flow guide pipe mounting hole 11 to absorb the heat of the rotor 1.2, and then the cooling liquid is recycled to the rotary connector 8 through the liquid outlet groove of the flow guide pipe 8, and can penetrate into the rotor to absorb the heat of the rotor, so that the rapid heat dissipation is realized.

As shown in fig. 12 to 14, one specific scheme is as follows: the liquid outlet groove is spiral along the outer wall of the guide pipe 8, and the cooling liquid flows back to the rotary connector 8 along the spiral guide pipe 8. The rotary connector 8 is a high-speed rotary connector, so that cooling liquid flows orderly inside and outside the guide pipe, and the cooling liquid flows along the spiral liquid outlet grooves, thereby prolonging the contact time of the liquid and the rotor and increasing the heat conduction quantity.

As shown in fig. 15, on the basis of the above technical solution, this embodiment further provides a flywheel energy storage system, including: the liquid cooling device is communicated with the cooling flow passage in the shell 4 and is used for providing cooling liquid for the cooling flow passage so as to accelerate heat conduction to the heating body and the receiving body.

Further, a spiral stator liquid cooling channel 41 is provided in the casing 4, and the liquid cooling device also supplies cooling liquid to the stator liquid cooling channel 41 for cooling the stator and the windings.

The liquid cooling device also supplies cooling liquid to the spinner 9 to dissipate heat from the rotor through the draft tube 8.

In the above scheme, on one hand, the liquid cooling device is connected with the stator liquid cooling channel 41 of the casing 4 through the stator liquid inlet pipeline and the stator liquid outlet pipeline respectively, and the cooling liquid provided by the liquid cooling device circularly flows in the stator liquid cooling channel 41 and is used for radiating the stator. On the other hand, the liquid cooling device is connected with the cooling flow channel 42 of the casing 4 through the liquid inlet pipeline of the receiving body and the liquid outlet pipeline of the receiving body respectively, and the cooling liquid provided by the liquid cooling device circularly flows in the cooling flow channel 42 and is used for radiating the heat of the receiving body 7. On the other hand, the liquid cooling device is respectively connected with the rotary connector 9 through a rotor liquid inlet pipeline and a rotor liquid outlet pipeline, cooling liquid provided by the liquid cooling device circularly flows in the guide pipe 8 and the guide pipe mounting hole 11 and is used for radiating the rotor, so that the combination of radiation and liquid cooling is realized, the stator and the rotor are radiated, the better radiating effect is realized, flywheel energy storage systems with different power sections can be used, the flywheel energy storage systems from hundred watts to megawatts are covered, and the reliability is improved.

And the three liquid cooling channels can be simultaneously cooled by sharing one liquid cooling device, so that the complexity, the system consumption and the occupied area of the liquid cooling system are reduced, and the volume and the cost required by the liquid cooling system are greatly reduced. And, can adjust the heat dissipation mode according to flywheel energy storage system's temperature, for example: when the temperature of the rotor is not high, only the heating element and the receiving body can be adopted for heat dissipation; when the temperature of the rotor is higher, the rotary connector can be further started to radiate the rotor through the flow guide pipe. The temperature of the stator and the rotor is controlled in a proper temperature range by adjusting the temperature and the flow of the cooling liquid.

Example III

On the basis of the technical scheme, the embodiment also provides an implementation mode of the flywheel motor rotor:

As shown in fig. 16, the flywheel motor rotor provided in this embodiment includes: rotor core 1 and magnet steel 2. Wherein, rotor core 1 is equipped with rotor pivot 3 in the rotor core. The outer side surface of the rotor core 1 is curved, and specifically, along the circumferential direction, the curved track of the outer side surface of the rotor core 1 is a sinusoidal line.

The magnet steel 2 is embedded in the rotor core 1, and a plurality of magnet steels 2 are arranged around the axis of the rotor core 1. The magnetic steel 2 is a permanent magnet.

According to the technical scheme provided by the embodiment, the rotor core is trimmed to form sine lines, so that uneven air gaps are formed, a sine air gap magnetic field is generated by descending under the condition of the same excitation magnetic potential, the fundamental wave duty ratio of the air gap magnetic field is improved, the harmonic wave duty ratio is reduced, loss is reduced, and the magnet demand can be reduced. In addition, by utilizing a plurality of permanent magnet steel blocking technologies, the eddy current path can be blocked, and loss can be restrained.

Based on the above technical solution, this embodiment provides a specific implementation manner: the rotor core 1 is provided with a magnetic steel groove, and the magnetic steel 2 is embedded in the magnetic steel groove. The magnetic steels 2 are divided into six groups, the six groups of magnetic steels 2 are distributed to form a regular hexagon, and gaps are reserved between two adjacent groups of magnetic steels.

One embodiment is: each group comprises two magnetic steels 2, and a gap is reserved between the two magnetic steels 2. The two magnetic steels in a group are collinear and are arranged in axisymmetric relation with the radius of the rotor shaft 3 passing through the gap between the two magnetic steels 2. Specifically, the opposite surfaces of two magnetic steels 2 in a group are planes, and two side surfaces of each magnetic steel 2 are perpendicular to the planes. The surfaces of two magnetic steels 2 in a group, which are opposite to each other, are irregularly shaped.

An insulating coating can be arranged between the magnetic steels 2 to further block the eddy current path.

The curved track at the position corresponding to the gap 4 between the two magnetic steels 2 is the peak of the sine line. Further, curved surface tracks at positions corresponding to the magnetic steels of each group are the same, namely tracks of sine lines corresponding to the six groups of magnetic steels are the same. And the curved surfaces at the corresponding positions of the gaps between two groups of adjacent magnetic steels 2 are in smooth transition.

In addition, the slot opening width of the stator core punching sheet can be reduced, the air gap length can be increased, and proper pole slot matching and winding modes can be selected, so that the harmonic loss is finally reduced.

Example IV

On the basis of the technical scheme, the embodiment also provides an implementation mode of the flywheel motor rotor:

As shown in fig. 17, the motor rotor provided in this embodiment includes: rotor shaft 3, rotor core 2 and magnet 1. Wherein, rotor core 2 cover is located rotor pivot 3.

The magnet 1 is formed by mixing and bonding permanent magnet powder and resin glue and through a magnet die, and is inserted into the rotor core 2.

According to the technical scheme provided by the embodiment, the magnet is formed by mixing and bonding permanent magnetic powder and resin glue and through a magnet die, so that the conductivity of the magnet can be effectively reduced, and the high-frequency eddy current loss on the surface of the magnet is reduced. And the method of mould forming is adopted, so that the shape and the size of the magnet are not limited by the shape and the cost of the raw materials of the rare earth permanent magnet, and the magnet is convenient to repair.

For example, the magnets can be formed into a sine shape through a sine-shaped die, so that the sine degree of the air-gap magnetic field can be effectively improved, and the loss is further reduced.

The number of the magnets 1 is plural, the magnets 1 are annular, and gaps are reserved between the magnets 1. The magnets 1 are divided into six groups, each group comprising two magnets 1; the two magnets 1 in each group are collinear, and the six groups of magnets 1 enclose a regular hexagon.

The two magnets 1 in a group are arranged in an axisymmetric way, and the symmetry axis is the radius of the rotor rotating shaft 3 passing through the gap between the two magnets 1.

The scheme adopts a rotor structure with an embedded magnet, and the high-frequency harmonic wave of the air gap magnetic field is filtered by the rotor core 2, so that the high-frequency harmonic wave magnetic field penetrating into the surface of the magnet 1 is reduced. Moreover, by adopting the embedded magnet type rotor structure, the roundness of the outer surface of the rotor can be effectively ensured, and the wind friction loss of the rotor at high speed can be reduced conveniently.

Further, the carbon fiber sheath 4 is sleeved on the periphery of the rotor core, and the carbon fiber sheath 4 has certain toughness and strength and can protect the rotor. Moreover, the embedded magnet type rotor structure can effectively ensure the roundness of the outer surface of the rotor, is more convenient for winding the carbon fiber sheath 4, and ensures the strength of the rotor.

The rotor core 2 is formed by laminating a plurality of silicon steel sheets, a magnet is inserted into the rotor core 2, the whole rotor core is installed on the rotor rotating shaft 3 through a heating sleeving process, and a carbon fiber sheath 4 is wrapped on the outer surface of the rotor core 2 to form a whole rotor structure.

The resin adhesive is specifically epoxy resin, permanent magnetic powder and the epoxy resin are mixed in a ratio of 1:1 and then are placed into a die to be bonded to form the magnet 1 with low conductivity, so that the conductivity of the magnet can be effectively reduced, and the high-frequency eddy current loss on the surface of the magnet is reduced. After the magnet 1 is embedded in the embedded rotor core 2, the whole body is magnetized by using a pulse magnetizing machine. The shape of the magnet 1 is determined by the mold shape structure, which can be modified to have an arc-shaped surface with better air gap magnetic field sine.

Based on the scheme, the flywheel energy storage motor comprises a stator and the motor rotor provided by any content, wherein the stator is sleeved outside the rotor, and the rotor can rotate relative to the stator.

The stator includes: a stator core 5 and a stator armature winding 6. The stator core 5 is formed by laminating annular silicon steel sheets, and the stator armature winding 6 is embedded in the stator core 5. The stator winding 6 adopts a form of winding a plurality of wires in parallel into a short-distance multi-phase winding, such as a six-phase winding, which can effectively restrain fifth and seventh harmonics.

According to the scheme, the magnet is formed by bonding the magnetic powder with the epoxy resin, so that the conductivity of the magnet can be reduced, the sine degree of an air gap magnetic field can be improved, the eddy current loss of a rotor body is restrained, the abrasion of rotor wind is restrained through the design of retaining the roundness of the outer surface of the rotor, and the winding form of the multiphase motor is used for further restraining magnetic field harmonic waves. Therefore, the scheme provided by the embodiment realizes the low-loss structural design of the motor rotor by simultaneously optimizing and suppressing the eddy current loss, wind friction loss and magnetic field harmonic waves.

In addition, the low-conductivity magnet 1 formed by bonding magnetic powder is inserted into a silicon steel sheet mounting hole of the rotor core 2, the magnet 1 realizes free repair through a die, the sine degree of an air gap magnetic field is effectively improved, and finally the whole magnetizing is used for completing the excitation process. The outer surface of the rotor core 2 does not need to adopt a repair design, so that the roundness of the outer surface of the rotor is ensured, the rotor loss can be effectively restrained, the temperature rise of a magnet is reduced, and the carbon fiber sheath 4 is convenient to wind to increase the strength of the rotor.

Example IV

On the basis of the technical scheme, the embodiment also provides a flywheel energy storage device, which is also called a flywheel energy storage motor, so as to solve the problems that the existing flywheel energy storage device needs to be additionally provided with a static seal or dynamic seal structure, and has excessive system auxiliary equipment and large volume.

Referring to fig. 18 and 19, the flywheel energy storage device provided in the present embodiment includes: the flywheel rotating shaft 2 is rotatably connected in the shell 1 through a bearing, and one end of the flywheel rotating shaft 2 extends to the outer side of the shell 1.

The vacuum suction assembly is positioned on the outer side of the shell 1; the vacuum suction assembly comprises a vacuum shell 4 and an impeller 3, the impeller 3 is fixed on the flywheel rotating shaft 2 and is driven by the flywheel rotating shaft 2 to rotate, and the vacuum shell 4 is covered on the outer side of the impeller 3 and is eccentrically arranged with the impeller 3; the casing 1 is provided with an air exhaust hole 6 communicated with the inner cavity of the casing 1 and the inner cavity of the vacuum casing 4, and the vacuum casing 4 is provided with an air exhaust hole 7 communicated with the inner cavity and the outside.

The inner cavity of the vacuum shell 4 is provided with a working medium 5, and in the rotating process of the impeller 3, the working medium 5 forms a closed ring body in the circumferential direction to obtain positive displacement vacuum, and the working medium is pumped from the shell 1 through a pumping hole 6 and is discharged from a vent hole 7 along with rotation.

The shell 1 is a cylindrical barrel body, a hollow cavity is formed in the shell 1, the shell 1 is preferably of a split type structure and comprises a shell body and a cover body which are detachably and fixedly connected, bearings are respectively arranged on the top wall and the bottom wall of the shell 1, and two ends of an airplane rotating shaft are respectively and rotatably connected with the shell 1 through the bearings; in one embodiment, the bearings are magnetic bearings, specifically, an upper magnetic bearing and a lower magnetic bearing are respectively arranged at two longitudinal ends of the casing 1, and two ends of the flywheel rotating shaft 2 are respectively connected with the casing 1 through the upper magnetic bearing and the lower magnetic bearing. The friction resistance between the flywheel rotating shaft 2 and the shell 1 is further reduced through the magnetic bearing, and the energy consumption is reduced.

One end of the flywheel rotating shaft 2 extends to the outer side of the casing 1, an impeller 3 is fixed at the tail end of the flywheel rotating shaft 2, the impeller 3 rotates under the driving of the flywheel rotating shaft 2, meanwhile, a vacuum shell 4 is covered on the outer side of the impeller 3 and eccentrically arranged with the impeller 3, an air suction hole 6 is formed at the assembling position of the shaft end of the flywheel rotating shaft 2 and the casing 1, a working medium 5 is arranged in the vacuum shell 4, the flywheel rotating shaft 2 drives the impeller 3 to rotate, and in the rotating process of the impeller 3, a closed ring body is formed by tool media in the circumferential direction to obtain a volume type pump structure, and the specific working principle is as follows: the vacuum shell 4 and the rotating shaft of the impeller 3 are eccentrically designed, the diameter of the impeller 3 is smaller than the inner diameter of the vacuum shell 4, the tail end of the high-speed rotating shaft of the flywheel is utilized to drive the impeller 3 to rotate, the impeller 3 rotates to enable oil in the vacuum working cavity to form an oil ring with equal thickness under the action of centrifugal force, at the moment, the oil ring on one side of the inner cavity of the vacuum shell 4 is just tangential to the hub of the impeller 3, and the oil ring on the other side is tangential to the top ends of blades. At this time, crescent spaces with different volumes formed by blade division are formed among the inner surface of the oil ring, the hub of the impeller 3 and the blades of the impeller 3.

When the impeller 3 rotates, the volume of the crescent space at the left side in fig. 2 is changed from small to large, so that the air pressure of the space is gradually reduced, and the space is designed to be communicated with the air suction hole 6, so that the air can be sucked into the inner cavity of the vacuum shell 4 from the flywheel cavity; in contrast, the crescent space on the right side of the figure is increased from small to large in volume, so that the air pressure of the space is gradually increased, the space is designed to be communicated with the external exhaust hole 7, and then the air can be discharged from the working cavity of the vacuum shell 4 to the surrounding environment, so that the complete air suction and exhaust process is realized, and the vacuum of the flywheel cavity is obtained.

The assembly position of the shaft end of the flywheel rotating shaft 2 and the flywheel shell 1 is directly used as the air suction hole 6 of the flywheel cavity and is directly connected with the vacuum suction assembly, so that the unidirectional flow of air can be ensured, and the air suction assembly also directly becomes a vacuum sealing structure at the position, and an additional static sealing cover or a dynamic sealing structure is not required to be designed, so that the vacuum acquisition and the vacuum sealing coupling of the flywheel energy storage device are integrated.

In a preferred embodiment, the working medium 5 is oil; specifically, the working medium 5 is cooling or lubricating medium oil within the casing 1.

The vacuum shell 4 can realize the oil rings with equal thickness and the working cavity by using oil as the working medium 5, and can directly utilize cooling or lubricating medium oil in the flywheel, thereby coupling the vacuum suction assembly, the vacuum sealing structure and the vacuum oil cooling structure into a system and realizing the great simplification of an auxiliary system of the flywheel energy storage device.

In one embodiment, the impeller 3 comprises an impeller 3 hub and a plurality of blades, wherein each blade is annularly and equidistantly arranged on the circumferential outer wall of the impeller 3 hub, and the distance between every two adjacent blades is gradually increased from inside to outside along the radial direction. Preferably, the impeller 3 is a straight blade impeller 3; and the impeller 3 hub and the blades are integrally arranged. Preferably, the impeller 3 is in key connection with the flywheel shaft 2 to facilitate assembly and disassembly.

In a preferred embodiment, the vacuum housing 4 is removably attached to the enclosure 1 by a fixed connection, such as a threaded fastener or the like, to facilitate removal.

The vacuum pumping assembly of the device is composed of an impeller 3 directly arranged at the tail end of a flywheel rotating shaft 2, a vacuum shell 4 and working medium 5 oil in the vacuum shell, the flywheel rotating shaft 2 is utilized to drive the impeller 3 to rotate, and a positive displacement vacuum obtaining structure is formed by the vacuum pumping assembly and an oil ring formed by the vacuum pumping assembly; the assembly position of the shaft end of the flywheel rotating shaft 2 and the flywheel shell 1 is used as an air extraction hole 6 of the flywheel cavity and is directly connected with the vacuum suction assembly, so that the vacuum sealing structure of the vacuum suction assembly is coupled into a whole, and the auxiliary system of the flywheel energy storage device is greatly simplified; and meanwhile, cooling or lubricating medium oil in the flywheel is used as a working medium 5, so that the structure of the flywheel energy storage device is further simplified.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element in question must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; may be mechanically connected, may be electrically connected or may communicate with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit or scope of the application. Thus, it is intended that the present application also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.

Claims (11)

1. The manufacturing method of the motor stator winding is characterized in that the stator winding comprises a stator core and an armature winding, wherein the armature winding is arranged into a ring shape by a stator bar, and the stator core is wound in the middle of the stator bar; the manufacturing method comprises the following steps:

Winding alkali-free glass fiber tapes impregnated with silicon carbide high-resistance paint around the periphery of the part of the stator bar outside the stator core;

and winding an alkali-free glass fiber tape impregnated with graphite paint around the part of the stator bar in the cladding area of the stator core.

2. The method as recited in claim 1, further comprising: and wrapping the iron-bearing asbestos belt around the part of the stator bar, which is positioned in the cladding area of the stator core.

3. The method according to claim 1 or 2, further comprising:

and sequentially winding a first semi-conductive self-adhesive tape, an insulating self-adhesive tape and a second semi-conductive self-adhesive tape around the periphery of the stator bar around which the glass fiber tape is arranged.

4. The method according to claim 1 or 2, further comprising:

The armature full-epoxy resin encapsulation mode is adopted to carry out insulation treatment on the stator winding, the encapsulating material is thermosetting flame-retardant casting epoxy resin, and the weight ratio of the main agent to the curing agent is 10:7.

5. The method of claim 4, wherein insulating the stator winding by means of armature full epoxy potting comprises:

Placing the stator winding in vacuum potting equipment;

mixing the main agent and the curing agent for 0.5-3 hours under the air pressure with the vacuum degree of 50Pa-800Pa to obtain mixed filler;

Pouring the mixed filler into the stator winding in a vacuum environment;

And (5) performing curing treatment.

6. A motor stator winding comprising: the stator iron core and the armature winding are arranged into a ring shape by a stator bar, and the stator iron core is wound in the middle of the stator bar;

an alkali-free glass fiber tape impregnated with silicon carbide high-resistance paint is wound around the periphery of the part of the stator bar, which is positioned outside the stator core;

And an alkali-free glass fiber tape impregnated with graphite paint is wound around the periphery of the part of the stator bar, which is positioned in the cladding area of the stator core.

7. The motor stator winding of claim 6 wherein the portion of the stator bar that is located within the stator core cladding area is further wrapped with an iron-containing asbestos tape.

8. A stator winding for an electrical machine according to claim 6 or claim 7 wherein the stator bar is further provided with a first semi-conductive self-adhesive tape, an insulating self-adhesive tape and a second semi-conductive self-adhesive tape wound around the periphery thereof in sequence.

9. An insulation testing system for insulation testing of a stator winding of an electric machine as claimed in any one of claims 6 to 8, comprising: the device comprises an alternating current power supply, a transformer, a capacitive voltage divider and a vacuum test cabin; the alternating current power supply and the transformer are used for providing an excitation power supply for the motor stator winding to be tested; the capacitive divider is used to measure the operating voltage of the motor stator windings.

10. An insulation testing method for testing a stator winding of an electric machine using the insulation testing system of claim 9, comprising:

Placing a motor stator winding in a vacuum test cabin;

regulating the air pressure in the vacuum test cabin to reach preset air pressure;

Adjusting the frequency of the alternating current power supply to reach a preset frequency;

And regulating the voltage of the alternating current power supply to gradually rise, and acquiring the current working voltage of the motor stator winding when the motor stator winding is determined to generate corona.

11. A flywheel energy storage motor, comprising: a motor stator winding and a motor rotor as claimed in any one of claims 1-8.