A high starting torque 2-pole high speed high voltage motor

Abstract

This invention proposes a high-starting-torque 2-pole high-speed high-voltage motor, comprising a frame and a rotating shaft, rotor core, and stator core housed therein. The rotor core has axially distributed ventilation holes along its circumference and radial air ducts spaced along its axial direction. The stator core also has radial air ducts spaced along its axial direction. The frame has a first air inlet and a first air outlet, and contains a guide shroud and an axial fan. External air enters the frame through the first air inlet, is guided by the guide shroud to the axial fan, and then splits into three paths: the first path enters the rotor core through the axial ventilation holes, then exits through the rotor and stator radial air ducts; the second path enters the air gap between the rotor and stator, then exits through the stator radial air duct; the third path flows through the end of the stator coils, exits through the gap between the stator core and the coils. This invention, through multiple parallel cooling air paths, allows for sufficient heat exchange between the air and the heat-generating components, effectively reducing motor temperature rise, decreasing winding copper losses, and improving motor operating efficiency.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a high-starting-torque 2-pole high-speed high-voltage motor. Background Technology

[0002] 2P (two-pole) high-speed, high-voltage, high-power motors possess advantages such as high speed and high power density, and are widely used in industries such as petroleum, chemical, coal, and metallurgy. With the continuous increase in single-unit capacity, the problem of motor heat generation has become increasingly prominent. During motor operation, components such as the stator windings, rotor copper busbars, and iron core generate a large amount of heat. If this heat cannot be dissipated effectively and in a timely manner, it will lead to excessively high motor temperature rise, accelerated aging of winding insulation, and increased bearing temperature. This not only shortens the motor's service life but also easily causes equipment failure, affecting the safe and stable operation of the unit. Therefore, the design of the ventilation and cooling system has become a key aspect of the research and development of high-power, high-speed motors.

[0003] In existing technologies, the common cooling method for 2-pole high-speed, high-voltage, high-power motors is as follows: cooling air enters the motor cavity from both ends, cools the stator winding ends, stator and rotor cores, and other heat-generating components, and then exits. However, the airflow structure of traditional motors is relatively simple, and the airflow path inside the motor is short. This results in insufficient heat exchange between the air and the heat-generating components, leading to higher motor temperatures. Especially for high-voltage motors with longer cores and higher power, the heat-generating components distributed along the axial direction are difficult to cool evenly and effectively. Localized overheating easily occurs in the central axial region, severely affecting the motor's reliability and service life.

[0004] Therefore, optimizing the airflow layout, extending the flow path of cooling air, and ensuring that each heat-generating component is cooled sufficiently and evenly within a limited space are technical challenges that need to be addressed in 2-pole high-speed high-voltage motors. Summary of the Invention

[0005] This invention proposes a high-starting torque 2-pole high-speed high-voltage motor, which solves the problems of poor heat dissipation caused by the simple airflow structure and short flow path of cooling air inside the motor in traditional motors.

[0006] The technical solution of this invention is implemented as follows:

[0007] The present invention provides a high starting torque 2-pole high speed high voltage motor, including a frame, wherein the frame is provided with a rotating shaft, a rotor core and a stator core, the rotor core is provided with a plurality of axial ventilation holes distributed circumferentially, and a plurality of rotor radial air ducts are provided axially at intervals, and the stator core is provided with a plurality of stator radial air ducts axially at intervals.

[0008] The base is provided with a first air inlet and a first air outlet, and the base is provided with a flow guide and a fan. The flow guide is used to guide the airflow to the fan.

[0009] Air from outside the chassis enters the chassis through the first air inlet, is then guided by the air deflector to the axial fan, and is split into three streams: The first airflow enters the rotor core through the axial ventilation hole, then flows through the rotor radial air duct and the stator radial air duct in sequence before flowing out from the first air outlet; The second airflow enters the air gap between the stator core and the rotor core directly through the end, then flows through the stator radial air duct and exits from the first air outlet. The third airflow passes through the end of the stator coil for cooling, then flows through the gap between the stator core and the stator coil before exiting from the first air outlet.

[0010] Preferably, the stator radial air ducts and rotor radial air ducts are arranged in an alternating manner.

[0011] Furthermore, the width of the rotor radial air duct is n times the width of the stator radial air duct, and the number of rotor radial air ducts is 1 / n of the number of stator radial air ducts.

[0012] Preferably, a heat dissipation silencer is provided on one side of the base. The heat dissipation silencer includes a housing, with second air inlets at both ends of the housing and a second air outlet on the side of the housing.

[0013] The bottom of the housing is an open structure and is connected to the side of the base where the first air inlet and the first air outlet are located; the housing is equipped with two air inlet baffles, which are respectively located on both sides of the first air outlet to separate the first air outlet from the first air inlets on both sides; the second air outlet is located on the side of the housing between the two air inlet baffles.

[0014] Outside air enters the housing through the second air inlet, then enters the base through the first air inlet for heat exchange, then returns to the housing through the first air outlet, and finally exits the housing through the second air outlet.

[0015] Furthermore, an air inlet guide plate is provided between the air inlet baffle and the side walls at both ends of the box. The air inlet guide plate is used to guide the airflow to turn inside the box, so as to extend the flow path of the airflow inside the box.

[0016] The box is also equipped with several staggered air outlet guide plates to guide the airflow to turn within the box, thereby extending the flow path of the airflow within the box; several of the air outlet guide plates are located in the area between two air inlet baffles, and the air outlet guide plates are perpendicular to the air inlet guide plates and air inlet baffles.

[0017] Furthermore, both the second air inlet and the second air outlet are equipped with louvers. The inner walls of the housing and the louvers, as well as the sides of the air inlet baffle, air inlet guide plate and air outlet guide plate, are all covered with sound-absorbing cotton, and the outside of the sound-absorbing cotton is pressed and fixed by a perforated mesh plate.

[0018] Specifically, the rotor core is formed by stacking several rotor laminations, and the two ends of the rotating shaft are fitted with rotor pressure rings, retaining rings and balance rings. The rotor pressure rings are used to press the rotor core; a locking nut is provided on the outside of the rotor pressure rings for axially locking the rotor core.

[0019] An end ring is fitted around the outside of the rotor pressure ring, and the end ring is used to fix the rotor copper busbar; the retaining ring is fitted around the outside of the end ring and is used to radially limit the end ring; the balance ring is located outside the retaining ring and is used to install the balance block.

[0020] Furthermore, the outer end face of the rotor pressure ring is provided with a plurality of bushings along the circumferential direction. The outer surface of the bushing is an arc surface that matches the inner surface of the end ring. The end ring is sleeved on the outside of the plurality of bushings. The bushings are used to circumferentially limit the end ring.

[0021] Furthermore, an axial gap is reserved between the retaining ring and the end ring to release the axial expansion of the end ring under hot conditions; the rotor pressure ring, retaining ring and balance ring are all provided with several through holes communicating with the axial ventilation holes.

[0022] Preferably, the outer edge of the rotor core is provided with an irregularly shaped groove that is narrow on the outside and wide on the inside, and a rotor copper busbar that is narrow on the outside and wide on the inside is embedded in the irregularly shaped groove.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) By setting axial ventilation holes and rotor radial air channels on the rotor core and stator radial air channels on the stator core, and cooperating with the air inlet, air outlet, guide shroud and fan on the frame, the external air is divided into three paths, which flow through the rotor interior, the stator-rotor air gap and the stator coil respectively, so that the cooling air forms multiple parallel and independent long path heat dissipation air paths inside the motor, and achieves targeted cooling of the main heat-generating components and unified collection and discharge; compared with the traditional single-path ventilation structure, the heat exchange between the cooling air and each heat-generating component is more sufficient, significantly reducing the overall temperature rise of the motor, effectively reducing the stator winding resistance, reducing the winding copper loss, thereby improving the motor operating efficiency, realizing energy saving and consumption reduction, and extending the service life of the motor; (2) By setting the stator radial air duct and the rotor radial air duct to be staggered, and making the width of the rotor radial air duct greater than the width of the stator radial air duct and the number of rotor radial air ducts less than the number of stator radial air ducts, this air duct structure changes the traditional straight-through air duct alignment mode, extends the airflow path between the stator and rotor, significantly increases the contact area and time between the cooling air and the iron core and windings, and further improves the heat dissipation efficiency. (3) The present invention provides a heat dissipation silencer with independent air inlet and outlet areas on one side of the base, and connects to the base through the open structure at the bottom of the box. It uses the second air inlet at both ends of the box to intake air and the second air outlet on the side of the box to exhaust air. An air inlet baffle is set inside the box to separate the first air outlet from the first air inlet on both sides, so that the external cold air and the internal hot air can go their own way in the box without interfering with each other, thus avoiding crosstalk between intake and exhaust air. On this basis, the intake path is extended by the intake guide plate and the exhaust path is extended by the staggered exhaust guide plates, so that the airflow turns and flows in an orderly manner in the box, extending the residence time of the airflow in the box. The sound energy in the airflow is fully absorbed by the sound-absorbing cotton during multiple turns and reflections, effectively reducing exhaust noise. At the same time, by extending the exhaust path to reduce the air outlet wind speed, the aerodynamic noise when the airflow is discharged is further reduced. (4) The present invention uses a rotor pressure ring to press the rotor core and a locking nut to axially lock the rotor core, preventing the rotor core from moving axially under high speed rotation and hot conditions; the end ring is sleeved outside the rotor pressure ring and the end ring is radially limited by a retaining ring sleeved outside the end ring, ensuring dynamic balance stability under hot conditions; the end ring is limited by a liner on the outer end face of the rotor pressure ring under hot conditions, ensuring uniform circumferential expansion of the end ring under hot conditions, preventing uneven expansion of the end ring and centrifugal force from causing rotor dynamic imbalance and motor vibration exceeding limits; an axial gap is reserved between the retaining ring and the end ring to release the axial expansion of the end ring under hot conditions, avoiding structural interference caused by thermal expansion; at the same time, through holes communicating with axial ventilation holes are opened on the rotor pressure ring, retaining ring and balance ring to ensure the integrity of the rotor ventilation and heat dissipation path.

[0024] (5) The present invention opens an irregularly shaped slot with a narrow outer edge and a wide inner edge on the outer edge of the rotor core, and embeds a rotor copper busbar with a narrow outer edge and a wide inner edge in the irregularly shaped slot; this structure utilizes the skin effect to concentrate the current in the upper part of the copper busbar near the slot opening when the motor starts, which effectively increases the rotor resistance and thus significantly improves the starting torque of the motor; the increase in starting torque enables the motor to complete the starting process quickly, effectively shortens the starting time, reduces the power consumption during the starting process, and achieves energy saving effect. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the internal partial structure of a high-starting torque 2-pole high-speed high-voltage motor according to the present invention.

[0027] Figure 2 for Figure 1 Enlarged view of part A in the middle.

[0028] Figure 3 This is a schematic cross-sectional view of the heat dissipation silencer along its length in this embodiment.

[0029] Figure 4 This is a schematic cross-sectional view of the heat dissipation silencer along the width direction in this embodiment.

[0030] Figure 5 This is a schematic diagram of the installation structure of the sound-absorbing cotton in this embodiment.

[0031] Figure 6 This is a schematic diagram of a partial radial cross-sectional structure of the rotor lamination in this embodiment.

[0032] Figure 7 This is a schematic diagram of a partial axial cross-sectional structure of the rotor core in this embodiment.

[0033] Figure 8 This is a schematic diagram of the internal cooling airflow of the motor in this embodiment.

[0034] In the diagram: 1. Base; 2. Shaft; 3. Rotor core; 4. Stator core; 5. Axial ventilation hole; 6. Rotor radial air duct; 7. Stator radial air duct; 8. First air inlet; 9. First air outlet; 10. Draft shroud; 11. Fan; 12. Stator coil; 13. Housing; 14. Second air inlet; 15. Second air outlet; 16. Air inlet baffle; 17. Air inlet guide plate; 18. Air outlet guide plate; 19. Sound-absorbing cotton; 20. Perforated mesh plate; 21. Rotor laminations; 22. Rotor pressure ring; 23. Protective ring; 24. Balance ring; 25. Locking nut; 26. End ring; 27. Rotor copper busbar; 28. Liner block; 29. ​​Irregular groove. Detailed Implementation

[0035] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0036] Reference Figures 1 to 8This invention provides a high starting torque 2-pole high-speed high-voltage motor, including a frame 1. The frame 1 has a rotating shaft 2, a rotor core 3, and a stator core 4 inside. The rotor core 3 has a plurality of axial ventilation holes 5 distributed circumferentially, and a plurality of rotor radial air ducts 6 spaced axially. The stator core 4 has a plurality of stator radial air ducts 7 spaced axially. The rotor core 3 is formed by stacking a plurality of rotor laminations 21. The axial ventilation holes 5 are evenly distributed circumferentially on the rotor laminations 21, forming an axial channel penetrating the rotor core 3 after stacking. The rotor radial air ducts 6 are formed by setting ventilation slots between each rotor lamination 21 segment, and are spaced axially along the rotor core 3, forming a ventilation path radiating from the inside of the rotor outward. The stator radial air ducts 7 are formed by setting ventilation slots between each stator lamination segment, and are spaced axially along the stator core 4, forming a radial channel penetrating the stator core 4. In this way, a complete airflow path is formed inside the rotor, with axial air intake and radial air exhaust, and a radial channel for airflow is formed on the stator core 4.

[0037] The base 1 is provided with a first air inlet 8 and a first air outlet 9, and the base 1 is provided with a guide shroud 10 and a fan 11 (an axial flow fan in this embodiment). The guide shroud 10 is used to guide the airflow to the fan 11. The fan 11 is mounted on the rotating shaft 2 and rotates synchronously with the rotor to provide power for the flow of cooling air. The guide shroud 10 is located outside the fan 11 and is used to gather the air entering the base 1 and guide it to the air intake area of ​​the fan 11, reducing the diffusion loss of airflow before entering the fan 11 and improving the intake efficiency of the fan 11.

[0038] Air from outside the base 1 enters the interior of the base 1 through the first air inlet 8, and is then guided to the axial fan 11 by the guide shroud 10 and split into three streams. The first air inlet 8 is located at both ends of the side of the base 1. After the air with a lower external temperature enters the interior of the base 1 through the first air inlet 8, it flows to the fan 11 under the guidance of the guide shroud 10. After being pressurized by the fan 11, the speed increases and it is split into three streams that enter different cooling channels to cool multiple heat-generating parts of the motor at the same time.

[0039] The first airflow enters the rotor core 3 through the axial ventilation hole 5, then flows sequentially through the rotor radial air duct 6 and the stator radial air duct 7 before exiting from the first air outlet 9. During motor operation, the rotor copper busbar 27 and the rotor core 3 itself generate a large amount of heat. The first airflow enters the axial ventilation hole 5 from both ends of the rotor, exchanging heat with the rotor core 3. After reaching different axial positions of the rotor core 3, the airflow radiates outward from the inside of the rotor through the rotor radial air ducts 6, further exchanging heat with the rotor core 3. It then enters the stator radial air duct 7, further carrying away heat from the stator core 4. This path covers the main heat-generating components such as the rotor core 3 and stator core 4, providing the longest cooling path and the most thorough heat exchange.

[0040] The second airflow enters the air gap between the stator core 4 and the rotor core 3 directly through both ends of the stator and rotor, and then flows through the stator radial air duct 7 before exiting from the first air outlet 9. The air gap between the stator and rotor is the core area for electromagnetic energy conversion in the motor. During operation, this area generates a large amount of heat due to the high-frequency alternating magnetic field. The second airflow enters the air gap directly through the motor end, flows along the air gap axis, cools the surface of the stator and rotor, and then exits through the stator radial air duct 7 to further cool the interior of the stator core 4.

[0041] The third airflow passes through the end of the stator coil 12 for cooling, then flows through the gap between the stator core 4 and the stator coil 12 before exiting from the first air outlet 9. The end of the stator coil 12 is the part of the stator winding that extends beyond both ends of the stator core 4. This part has concentrated resistance loss, generates a large amount of heat, and is located at the end of the motor. The third airflow passes directly through the surface of the end of the stator coil 12 to cool this part specifically, and then exits through the gap between the stator core 4 and the stator coil 12, further cooling the stator core 4 and the stator coil 12.

[0042] The three airflows mentioned above flow in parallel inside the motor, cooling key heat-generating parts such as the rotor, stator, stator-rotor air gap, and stator coil 12 from different paths. Finally, they converge at the first air outlet 9 and are discharged, achieving comprehensive coverage and efficient cooling of all heat-generating components of the motor.

[0043] Preferably, such as Figure 2 As shown, the stator radial air ducts 7 and rotor radial air ducts 6 are arranged in an alternating manner. If the stator radial air ducts 7 and rotor radial air ducts 6 are aligned, the airflow will directly enter the stator radial air ducts 7 after exiting the rotor radial air ducts 6, resulting in a short residence time within the air ducts and insufficient heat exchange. This embodiment adopts an alternating arrangement, that is, the stator radial air ducts 7 and rotor radial air ducts 6 are axially offset rather than directly opposite each other. This causes the airflow to travel a certain distance along the air gap or inside the stator after exiting the rotor radial air ducts 6 before entering the stator radial air ducts 7. This prolongs the airflow path between the stator and rotor, increases the contact area and contact time between the air and the iron core, and makes heat exchange more sufficient. At the same time, it avoids the high-speed airflow noise generated by direct airflow paths.

[0044] Furthermore, such as Figure 2As shown, the width of the rotor radial air duct 6 is n times the width of the stator radial air duct 7 (twice in this embodiment), and the number of rotor radial air ducts 6 is 1 / n of the number of stator radial air ducts 7. The rotor radial air ducts 6 are wider and fewer in number, while the stator radial air ducts 7 are narrower and more numerous. The staggered arrangement of the two allows the airflow to flow out from the wide and sparse rotor radial air ducts 6, and after bypassing and diverting, enter the narrow and dense stator radial air ducts 7. This increases the flow path length of the airflow between the stator and rotor and the degree of airflow turbulence, further improving the heat dissipation effect.

[0045] Preferably, such as Figure 1 , 3 As shown in Figure 4, a heat dissipation silencer is provided on one side of the base 1. The heat dissipation silencer includes a housing 13. The two ends of the housing 13 are provided with second air inlets 14, and the side of the housing 13 is provided with a second air outlet 15. The heat dissipation silencer is located outside the base 1 and is used to guide external cold air into the motor, while absorbing the noise carried by the hot air discharged from the motor through the first air outlet 9.

[0046] The bottom of the housing 13 is open and connects to one side of the base 1 where the first air inlet 8 and the first air outlet 9 are located. The housing 13 has two air inlet baffles 16 inside, which are respectively located on both sides of the first air outlet 9 to separate the first air outlet 9 from the first air inlets 8 on both sides. The second air outlet 15 is located on the side of the housing 13 between the two air inlet baffles 16. The air inlet baffles 16 extend downward from the top of the housing 13 to connect with the surface of the base 1, dividing the interior of the housing 13 into air inlet areas on both sides and air outlet areas in the middle, so that the air inlet and air outlet do not interfere with each other inside the housing 13. External cold air enters the air intake areas on both sides through the second air inlets 14 at both ends of the housing 13 and then flows down to the first air inlet 8 to enter the base 1; hot air is discharged from the first air outlet 9 and then enters the air outlet area between the two air intake partitions 16, and is discharged through the second air outlet 15. The air intake path and the air outlet path are spatially independent of each other, which avoids crosstalk between the cold air entering the housing 13 and the hot air being discharged, and ensures that the air entering the motor is always the cool external cold air.

[0047] Outside air enters the housing 13 through the second air inlet 14, then enters the base 1 through the first air inlet 8 for heat exchange, and then returns to the housing 13 through the first air outlet 9, finally exiting the housing 13 through the second air outlet 15. The second air inlet 14 and the second air outlet 15 are separately arranged on the housing 13 and have different directions, further avoiding mutual interference between the air intake and exhaust.

[0048] Furthermore, such as Figure 3 , 4As shown, an air inlet guide plate 17 is provided between the air inlet baffle 16 and the side walls at both ends of the housing 13. The air inlet guide plate 17 is used to guide the airflow to turn within the housing 13, thereby extending the flow path of the airflow within the housing 13. The air inlet guide plate 17 is a plate-shaped component that is inclinedly set in the air inlet area. After the external cold air enters the housing 13 through the second air inlet 14, it turns multiple times along the inner wall of the housing 13 under the guidance of the air inlet guide plate 17 before entering the first air inlet 8. This extends the flow path of the airflow within the air inlet area, making the airflow more uniform and stable before entering the motor. At the same time, it extends the contact time between the airflow and the sound-absorbing cotton 19, reducing the air inlet noise.

[0049] The housing 13 is further provided with several staggered air outlet guide plates 18, which are used to guide the airflow to turn within the housing 13, thereby extending the flow path of the exhaust airflow within the housing 13. Several of these air outlet guide plates 18 are located in the area between two air inlet baffles 16, and the air outlet guide plates 18 are perpendicular to the air inlet guide plates 17 and the air inlet baffles 16 (because the second air inlet 14 and the second air outlet are located on adjacent sides of the housing 13, the second air inlet 14 is located on the left and right sides of the housing 13, and the second air outlet 15 is located on the front and rear sides of the housing 13). The air outlet guide plates 18 are plate-shaped components staggered within the air outlet area, extending downwards from the top wall of the housing 13 or upwards from the bottom of the housing 13 to the inner wall of the other side. Adjacent air outlet guide plates 18 extend alternately from opposite upper and lower inner walls to form a tortuous labyrinthine channel. After the hot air enters the air outlet area through the first air outlet 9, it turns multiple times along a tortuous path under the guidance of each air outlet guide plate 18 before reaching the second air outlet 15 for discharge. This prolongs the flow path and residence time of the hot air in the air outlet area, allowing the sound energy in the airflow to be fully absorbed and attenuated during the multiple turns and reflections, while also reducing the wind speed at the air outlet.

[0050] Furthermore, such as Figure 3-5As shown, both the second air inlet 14 and the second air outlet 15 are equipped with louvers. The inner walls of the housing 13 and the louvers, as well as the sides of the air inlet baffle 16, air inlet guide plate 17, and air outlet guide plate 18, are all covered with sound-absorbing cotton 19. The exterior of the sound-absorbing cotton 19 is pressed and fixed by a perforated mesh plate 20. The louvers consist of several parallel blades, ensuring smooth airflow while also providing some dust protection. The sound-absorbing cotton 19 is laid on the inner walls of the housing 13, the inner walls of the louvers, and the sides of each guide plate, forming a sound-absorbing layer covering the entire airflow channel. The noise energy carried by the airflow within the housing 13 is absorbed and dissipated by the fiber structure of the sound-absorbing cotton 19. The perforated mesh plate 20 covers the exterior of the sound-absorbing cotton 19 and is fixed to the surface of the housing 13 or the guide plate with screws. This is used to press and fix the sound-absorbing cotton 19, preventing high-speed airflow from blowing it away or causing it to fall off, thus ensuring the structural stability and long-term reliability of the sound-absorbing cotton 19. The sound-absorbing cotton 19 is laid to cover all the inner walls of the air inlet and outlet areas as well as the two sides of each guide plate, ensuring that the airflow can fully contact the sound-absorbing cotton 19 no matter what path it flows in the box 13, maximizing the noise reduction effect.

[0051] Specifically, such as Figure 6 , 7 As shown, the two ends of the rotating shaft 2 are fitted with rotor pressure rings 22, retaining rings 23, and balance rings 24. The rotor pressure rings 22 are used to press the rotor core 3. A locking nut 25 is provided on the outer side of the rotor pressure rings 22 for axially locking the rotor core 3. The rotor laminations 21 are stacked and pressed together from both ends by the rotor pressure rings 22, so that the laminations fit tightly together, preventing the increase of magnetic resistance or the laminations from loosening due to gaps between the laminations. The locking nut 25 is screwed onto the threaded section at the end of the rotating shaft 2 and abuts against the outer end face of the rotor pressure rings 22, fixing the rotor pressure rings 22 and the rotor core 3 as a whole onto the rotating shaft 2. The locking nut 25 provides a reliable axial locking force to prevent the rotor core 3 from moving axially due to thermal expansion under hot conditions.

[0052] An end ring 26 is fitted around the outside of the rotor pressure ring 22, and the end ring 26 is used to fix the rotor copper busbars 27. A retaining ring 23 is fitted around the end ring 26 to radially limit the end ring 26. A balance ring 24 is located outside the retaining ring 23 and is used to install balance blocks. The end ring 26 is a ring conductor, located at both ends of the rotor core 3, connecting the ends of all the rotor copper busbars 27 together to form a short-circuit ring for the squirrel-cage rotor bar circuit. The end ring 26 is fitted around the outside of the rotor pressure ring 22 with a clearance fit. The retaining ring 23 is a high-strength metal ring, heat-fitted around the end ring 26, and fixedly connected to the shaft 2, forming a radial constraint on the end ring 26 from the outside. During high-speed rotation, the end ring 26 is subjected to huge centrifugal force. The radial limiting effect of the retaining ring 23 on the end ring 26 keeps the radial expansion of the end ring 26 under centrifugal force within the allowable range, avoiding rotor dynamic imbalance due to excessive radial expansion of the end ring 26. The balance ring 24 is located outside the retaining ring 23 and is equipped with balance blocks through a dovetail groove structure. It is used to adjust the mass distribution of the rotor during rotor dynamic balancing tests and on-site calibration.

[0053] Furthermore, such as Figure 7 As shown, the outer end face of the rotor pressure ring 22 is provided with a plurality of bushings 28 along the circumferential direction. The outer surface of the bushings 28 is an arc surface adapted to the inner surface of the end ring 26. The end ring 26 is sleeved on the outside of the bushings 28, and the bushings 28 are used to circumferentially limit the end ring 26. The bushings 28 and the rotor pressure ring 22 are integrally formed (by machining). The radius of curvature of the outer arc surface of the bushings 28 is the same as the radius of curvature of the inner surface of the end ring 26. After the end ring 26 is sleeved on the outside of the bushings 28, the bushings 28 provide circumferential support and positioning for the end ring 26, so that the end ring 26 is uniformly stressed in the circumferential direction, avoiding uneven deformation of the end ring 26 in the circumferential direction due to centrifugal force and thermal expansion.

[0054] Furthermore, an axial gap is reserved between the retaining ring 23 and the end ring 26 to release the axial expansion of the end ring 26 under hot conditions. The rotor pressure ring 22, retaining ring 23, and balance ring 24 are all provided with several through holes communicating with the axial ventilation holes 5. The retaining ring 23 and the end ring 26 maintain a predetermined gap in the axial direction without contacting each other. When the motor is running in a hot state, the end ring 26 elongates axially due to temperature rise. This gap provides space for the axial thermal expansion of the end ring 26, preventing the end ring 26 from being squeezed against the retaining ring 23 after axial expansion, thus avoiding the retaining ring 23 being axially pushed and losing its radial limiting function. The through holes on the rotor pressure ring 22, retaining ring 23, and balance ring 24 are aligned and connected with the axial ventilation holes 5 on the rotor core 3, ensuring that the first cooling airflow can smoothly enter the axial ventilation holes 5 from the rotor end without being blocked by the aforementioned structural components, ensuring the integrity and unobstructedness of the internal ventilation path of the rotor.

[0055] In this embodiment, the retaining ring 23 and the rotating shaft 2 can be fitted with a heat-shrink fitting. That is, the retaining ring 23 is heated to expand its inner diameter and then fitted onto the rotating shaft 2. After cooling, it shrinks and tightens around the rotating shaft 2, forming a strong interference fit. The rotor core 3 and the rotating shaft 2 can also use an interference fit instead of the traditional key drive. The interference amount is determined based on the mechanical torque to be transmitted, which can reduce the weakening of the shaft strength caused by the keyway on the rotating shaft 2, and at the same time avoid the adverse effects of the keyway on the rotor dynamic balance.

[0056] In this embodiment, the two ends of the rotor copper busbar 27 can be chamfered to reduce thermal expansion and thermal stress under hot conditions.

[0057] Preferably, such as Figure 6 As shown, the outer edge of the rotor core 3 has a narrow-on-the-outer, wider-on-the-inner irregularly shaped slot 29, into which a rotor copper busbar 27, also narrow-on-the-outer, wider-on-the-inner shape, is embedded. The irregularly shaped slot 29 is a deep slot shape, with a narrower opening near the outer surface of the rotor and a wider bottom portion near the inner surface, exhibiting a radially narrow-on-the-outer, wider-on-the-inner shape. The rotor copper busbar 27 matches the shape of the irregularly shaped slot 29, also having a narrow-on-the-outer, wider-on-the-inner irregularly shaped cross-section. The rotor laminations 21 employ a parallel tooth structure, meaning the side walls of the teeth between adjacent irregularly shaped slots 29 are parallel to each other, and the tooth width remains consistent radially. During motor startup, the rotor frequency is high, resulting in a significant skin effect. The current concentrates in the upper narrow opening region of the copper busbar near the slot opening, effectively reducing the effective cross-sectional area of ​​the conductor and increasing the rotor resistance, thereby improving the starting torque. As the speed increases to the rated speed, the rotor frequency decreases, the skin effect weakens, and the current gradually expands towards the lower part of the copper busbar. The rotor resistance automatically returns to its normal value, ensuring the efficiency of the motor during normal operation. The parallel tooth structure eliminates local distortions in the magnetic flux density of the rotor teeth, reduces the saturation of the rotor teeth, and improves the electromagnetic performance and vibration characteristics of the motor.

[0058] like Figure 8 As shown, the heat dissipation process of the high-speed, high-voltage motor in this embodiment is as follows:

[0059] Cooler external air enters the housing 13 through the second air inlets 14 at both ends of the heat dissipation silencer. Guided by the air inlet guide plate 17, it flows in a directional direction within the housing 13 and then enters the motor through the first air inlet 8 on the base 1. The air entering the base 1 flows to the axial fan 11 under the guidance of the air guide shroud 10. After being pressurized by the fan 11, it is split into three streams:

[0060] The first airflow enters the axial ventilation hole 5 of the rotor core 3 from both ends of the rotor through the through holes on the balance ring 24, the retaining ring 23 and the rotor pressure ring 22, and passes through the interior of the rotor core 3 axially, directly carrying away the heat generated inside the rotor core 3; when the airflow reaches the rotor radial air duct 6 at each axial position of the rotor core 3, it radiates outward from the inside of the rotor and further carries away the heat inside the rotor core 3, and then enters the stator radial air duct 7 on the stator core 4 through the misaligned stator-rotor air gap to reach the first air outlet 9, and carries away the heat of the stator core 4.

[0061] The second airflow passes through both ends of the iron core and directly enters the air gap between the stator iron core 4 and the rotor iron core 3. It flows along the axial direction of the air gap, cools the inner surface of the stator and the outer surface of the rotor, and then reaches the first air outlet 9 through the stator radial air duct 7, further carrying away the heat inside the stator iron core 4.

[0062] The third airflow passes through the end of the stator coil 12, directly cooling the part of the stator coil 12 that extends beyond the two ends of the iron core. Then, it reaches the first air outlet 9 through the gap between the stator iron core 4 and the stator coil 12, and takes away the heat of the stator iron core 4 and the stator coil 12 in one step.

[0063] After the three airflows together cool the key heat-generating parts such as the rotor interior, stator interior, stator-rotor air gap, and stator coil 12, they converge from their respective paths to the first air outlet 9 on the base 1. The hot air carrying heat enters the heat dissipation silencer outlet area through the first air outlet 9 and flows along a tortuous path inside the housing 13 under the guidance of the air outlet guide plate 18. During the flow, the noise energy carried by the hot air is fully absorbed by the sound-absorbing cotton 19 laid on the inner wall of the housing 13 and the sides of each guide plate. Finally, it is discharged from the housing 13 through the second air outlet 15, completing the complete heat dissipation process.

[0064] 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 high-starting-torque 2-pole high-speed high-voltage motor, comprising a frame (1), wherein the frame (1) is internally provided with a rotating shaft (2), a rotor core (3), and a stator core (4), characterized in that, The rotor core (3) has several axial ventilation holes (5) distributed along the circumference and several rotor radial air ducts (6) spaced along the axial direction. The stator core (4) has several stator radial air ducts (7) spaced along the axial direction. The base (1) is provided with a first air inlet (8) and a first air outlet (9), and the base (1) is provided with a flow guide (10) and a fan (11) inside. The flow guide (10) is used to guide the airflow to the fan (11). Air from outside the base (1) enters the interior of the base (1) through the first air inlet (8), and is then guided by the guide shroud (10) to the axial fan (11) where it is split into three streams: The first airflow enters the rotor core (3) through the axial ventilation hole (5), then flows through the rotor radial air duct (6) and the stator radial air duct (7) in sequence, and then flows out from the first air outlet (9); The second airflow enters directly into the air gap between the stator core (4) and the rotor core (3) through the end, then flows through the stator radial air duct (7) and flows out from the first air outlet (9); The third airflow passes through the end of the stator coil (12) for cooling, then flows through the gap between the stator core (4) and the stator coil (12) and flows out from the first air outlet (9).

2. The high starting torque 2-pole high-speed high-voltage motor as described in claim 1, characterized in that, The stator radial air ducts (7) and rotor radial air ducts (6) are arranged in an alternating manner.

3. A high starting torque 2-pole high-speed high-voltage motor as described in claim 2, characterized in that, The width of the rotor radial air duct (6) is n times the width of the stator radial air duct (7), and the number of rotor radial air ducts (6) is 1 / n of the number of stator radial air ducts (7).

4. A high starting torque 2-pole high-speed high-voltage motor as described in claim 1, characterized in that, The base (1) is provided with a heat dissipation silencer on one side. The heat dissipation silencer includes a housing (13). The two ends of the housing (13) are provided with a second air inlet (14), and the side of the housing (13) is provided with a second air outlet (15). The bottom of the housing (13) is an open structure and is connected to the side of the base (1) where the first air inlet (8) and the first air outlet (9) are provided; the housing (13) is provided with two air inlet baffles (16), which are respectively located on both sides of the first air outlet (9) to separate the first air outlet (9) from the first air inlets (8) on both sides; the second air outlet (15) is located on the side of the housing (13) between the two air inlet baffles (16); External air enters the housing (13) through the second air inlet (14), then enters the base (1) through the first air inlet (8) for heat exchange, and then returns to the housing (13) through the first air outlet (9), and finally exits the housing (13) through the second air outlet (15).

5. A high starting torque 2-pole high-speed high-voltage motor as described in claim 4, characterized in that, An air inlet guide plate (17) is provided between the air inlet baffle (16) and the side walls at both ends of the box (13). The air inlet guide plate (17) is used to guide the airflow to turn inside the box (13) so as to extend the flow path of the air inlet in the box (13). The box (13) is also provided with several staggered air outlet guide plates (18) to guide the airflow to turn inside the box (13) so as to extend the flow path of the air outlet in the box (13); several of the air outlet guide plates (18) are located in the area between two air inlet baffles (16), and the air outlet guide plates (18) are perpendicular to the air inlet guide plates (17) and the air inlet baffles (16).

6. A high starting torque 2-pole high-speed high-voltage motor as described in claim 5, characterized in that, The second air inlet (14) and the second air outlet (15) are both equipped with louvers. The inner walls of the box body (13) and the louvers, as well as the sides of the air inlet baffle (16), air inlet guide plate (17) and air outlet guide plate (18), are all covered with sound-absorbing cotton (19), and the outside of the sound-absorbing cotton (19) is pressed and fixed by a perforated mesh plate (20).

7. A high starting torque 2-pole high-speed high-voltage motor as described in claim 1, characterized in that, The rotor core (3) is formed by stacking several rotor laminations (21). The two ends of the rotating shaft (2) are fitted with rotor pressure rings (22), retaining rings (23) and balance rings (24). The rotor pressure rings (22) are used to press the rotor core (3). The outer side of the rotor pressure rings (22) is provided with locking nuts (25) for axially locking the rotor core (3). An end ring (26) is fitted around the outside of the rotor pressure ring (22), and the end ring (26) is used to fix the rotor copper busbar (27); the guard ring (23) is fitted around the outside of the end ring (26) and is used to radially limit the end ring (26); the balance ring (24) is located outside the guard ring (23) and is used to install the balance block.

8. A high starting torque 2-pole high-speed high-voltage motor as described in claim 7, characterized in that, The outer end face of the rotor pressure ring (22) is provided with a plurality of liner blocks (28) along the circumferential direction. The outer surface of the liner block (28) is an arc surface that matches the inner surface of the end ring (26). The end ring (26) is sleeved on the outside of the plurality of liner blocks (28). The liner blocks (28) are used to circumferentially limit the end ring (26).

9. A high starting torque 2-pole high-speed high-voltage motor as described in claim 7, characterized in that, An axial gap is reserved between the retaining ring (23) and the end ring (26) to release the axial expansion of the end ring (26) under hot conditions; the rotor pressure ring (22), the retaining ring (23) and the balance ring (24) are all provided with several through holes that communicate with the axial ventilation holes (5).

10. A high-starting-torque 2-pole high-speed high-voltage motor as described in claim 1, characterized in that, The outer edge of the rotor core (3) is provided with a shaped groove (29) that is narrow on the outside and wide on the inside, and a rotor copper busbar (27) that is narrow on the outside and wide on the inside is embedded in the shaped groove (29).

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