An ultra-high voltage motor stator end portion air path cooling structure

Abstract

The application relates to a stator end part air channel cooling structure of an ultrahigh-voltage motor, relates to the technical field of motor cooling, and comprises the following parts: a rotor comprising an inner fan; a stator comprising a stator coil; a shell provided with an inner cavity, a side wall of the shell being provided with a first air port and a second air port; a sealing and separating assembly comprising a first separating piece, a sealing filler and a second separating piece, the first separating piece being arranged between the stator coil and the side wall of the shell, the second separating piece being arranged between the stator coil and the inner fan, a gap existing between the first separating piece and the second separating piece for the stator coil to extend out, the sealing filler being filled between the gap and the stator coil, the sealing and separating assembly separating the inner cavity into a first cavity and a second cavity, the first air port being in communication with the first cavity, and the second air port being in communication with the second cavity. The application realizes air channel isolation through the sealing and separating assembly, the end part of the stator coil extends out through the gap, the gap is sealed and filled through the sealing filler, axial space occupation is reduced, the end part of the stator coil is cooled in a targeted manner, and the cooling efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of motor cooling technology, and in particular to a cooling structure for the stator end of an ultra-high voltage motor. Background Technology

[0002] Three-phase asynchronous squirrel-cage motors are widely used in industrial production due to their simple structure, reliable operation, and convenient maintenance. For medium and large-sized motors, especially when driving high-load equipment such as compressors, the enormous heat generated during operation requires an efficient cooling system to dissipate, ensuring the lifespan of the motor's insulation materials and operational reliability.

[0003] Currently, common internally cooled three-phase asynchronous squirrel-cage motors typically employ radial ventilation or a hybrid axial-radial ventilation structure. For example... Figure 1 As shown, in a high-speed 2-pole (2P) motor, the commonly used air cooling scheme is as follows: internal fans are installed at both ends of the motor rotor, and the cooling airflow is isolated and guided by the wind baffle (or air guide) fixed on the inner wall of the frame. The cooling air is forced to pass through the radial ventilation groove of the stator core under the drive of the fan, and at the same time, some airflow is blown to the end of the stator coil.

[0004] However, to achieve sufficient electrical insulation strength, the stator coil ends of ultra-high voltage motors are made very long to obtain a greater creepage distance. Therefore, when existing cooling structures are applied to ultra-high voltage (such as 22kV) and high-speed (2P) motors, their axial dimensions increase significantly. High-speed motors, to meet stringent mechanical and dynamic requirements such as rotor deflection and critical speed, must minimize the frame length to improve structural rigidity, resulting in extremely limited axial space. Furthermore, existing wind deflector structures require welding the air guide base to the inner wall of the thin-walled frame before installing the wind deflector. This component itself occupies considerable axial installation space, making installation difficult and hindering the compactness of motor designs. Existing wind deflector isolation airflow structures cannot suppress vibrations at the coil ends caused by high speeds through airflow design, nor can they achieve targeted heat dissipation of the coil ends by the cooling air, resulting in low cooling efficiency. Utility Model Content

[0005] The purpose of this application is to provide a cooling structure for the stator end of an ultra-high voltage motor to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the technical solution adopted in this application is as follows: This application provides a stator end cooling structure for an ultra-high voltage motor, including a rotor, a stator, a housing, and a sealing and partitioning assembly. The rotor includes a shaft and a rotor core, with two internal fans spaced axially on the shaft, and the rotor core positioned between the two internal fans. The stator includes a stator core and stator coils. The housing has an inner cavity that houses the rotor and stator. At least a first air vent and a second air vent are provided on the side wall of the housing away from the shaft. The first air vent corresponds to the axially outer region of the internal fans, and the second air vent corresponds to the stator core. The sealing and partitioning assembly includes a first partition, a sealing filler, and a second partition. The first partition is positioned between the stator coils and the side wall of the housing, and the second partition is positioned between the stator coils and the internal fans. A gap exists between the first and second partitions for the stator coils to extend out. The sealing filler is filled between the gap and the stator coils, so that the sealing and partitioning assembly divides the inner cavity into a first cavity and a second cavity. The first air vent communicates with the first cavity, and the second air vent communicates with the second cavity.

[0007] Furthermore, the first separator includes a first ring plate and a second ring plate. The side wall of the housing is provided with a mounting portion extending radially. The outer circular end of the first ring plate is fixedly connected to the mounting portion. The inner circular end of the first ring plate is fitted and fixed to the outer circular end of the second ring plate. The inner circular end of the second ring plate is in contact with the stator coil.

[0008] Furthermore, both the first ring plate and the second ring plate are provided with binding holes at the joint. The first ring plate and the second ring plate are fixed by passing binding ropes through the binding holes, and polysulfone felt is filled in the gap between the first ring plate and the second ring plate.

[0009] Furthermore, a stator pressure ring is provided on the stator core along its circumference, and a support screw extending axially is fixedly connected to the stator pressure ring. The end of the support screw away from the stator pressure ring is connected to the second ring plate.

[0010] Furthermore, the second ring plate is provided with a U-shaped slot, one end of the support screw passes through the U-shaped slot, and the second ring plate and the support screw are tightly connected by a polyester fiberglass rope.

[0011] Furthermore, the first ring plate is connected to the mounting part by bolts, and a gasket is provided between the first ring plate and the mounting part.

[0012] Furthermore, the sealing filler includes thermally expandable glass mat and sealant.

[0013] Furthermore, the second separator includes an insulating sleeve, which is fixed to the inner circle of the stator coil, and the outer end face of the insulating sleeve is in contact with the stator coil, and the insulating sleeve covers the inner fan.

[0014] Furthermore, the insulating sleeve is fixedly connected to the stator coil via a polyester fiberglass rope.

[0015] Furthermore, the housing includes a front cover plate, a rear cover plate, a top plate, a front bearing mechanism, and a rear bearing mechanism. The front cover plate is fixedly connected to the front bearing mechanism, and the front bearing mechanism is connected to the rotating shaft. The rear cover plate is fixedly connected to the rear bearing mechanism, and the rear bearing mechanism is connected to the rotating shaft. The top plate is fixedly connected to the front cover plate and the rear cover plate to form an inner cavity. The top plate is provided with a first air vent and a second air vent.

[0016] The beneficial effects of the technical solution provided in this application include at least the following: (1) This application achieves air path isolation through a sealing partition assembly, and the end of the stator coil extends through the gap between the first partition and the second partition, and is then sealed and filled by a sealing filler, thereby reducing the axial space occupied, meeting the space limitation of the ultra-high voltage motor, and enabling targeted heat dissipation of the end of the stator coil, avoiding the risk of overheating of the stator end of the ultra-high voltage motor, and extending the service life of the motor.

[0017] (2) This application fills the gap between the first partition and the second partition with a sealing filler to prevent cooling air leakage and direct the cooling air to flow through the stator core, effectively reducing heat dissipation efficiency loss and improving heat dissipation efficiency.

[0018] (3) This application limits the radial movement of the stator coil end by using the first separator and the second separator respectively, and uses the sealing filler to wrap and fill the coil end to form a fixed limit on the coil end, effectively limiting the radial vibration of the coil end, avoiding insulation wear or structural fatigue caused by the vibration of the coil, and improving the safety and stability of motor operation. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the embodiments of the present application to explain the application and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of an existing airflow cooling structure; Figure 2 This is a partial cross-sectional schematic diagram of the cooling structure of the stator end air passage of the ultra-high voltage motor in one embodiment of the present invention; Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0020] Explanation of key figure labels: 100. Housing; 111. First cavity; 112. Second cavity; 120. First air vent; 130. Second air vent; 140. Front cover plate; 150. Rear cover plate; 160. Top plate; 161. Mounting part; 171. Front bearing mechanism; 172. Rear bearing mechanism; 210. Rotating shaft; 220. Rotor core; 230. Internal fan; 310. Stator core; 311. Stator pressure ring; 320. Stator coil; 330. Support screw; 400. Sealing and partitioning assembly; 410. First partition; 411. First ring plate; 412. Second ring plate; 413. Gasket; 414. U-shaped slot; 420. Sealing filler; 430. Second partition. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] In this specification, identical components are represented by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "upper," and "lower" used in the following description refer to directions in the accompanying drawings, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions towards or away from a specific component, respectively. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this specification, "multiple" means two or more.

[0023] Example Please see Figures 2-3A stator end cooling structure for an ultra-high voltage motor includes a rotor, a stator, a housing 100, and a sealing and separating assembly 400. The rotor includes a shaft 210 and a rotor core 220. Two internal fans 230 are axially spaced on the shaft 210, and the rotor core 220 is disposed between the two internal fans 230. The stator includes a stator core 310 and stator coils 320. The housing 100 has an inner cavity that houses the rotor and stator. The side wall of the housing 100 away from the shaft 210 has at least a first air vent 120 and a second air vent 130. The first air vent 120 corresponds to the axially outer region of the internal fans 230, and the second air vent 130 is correspondingly disposed with respect to the stator core 310. The sealing and partitioning assembly 400 includes a first partition 410, a sealing filler 420, and a second partition 430. The first partition 410 is disposed between the stator coil 320 and the side wall of the housing 100, and the second partition 430 is disposed between the stator coil 320 and the internal fan 230. There is a gap between the first partition 410 and the second partition 430 for the stator coil 320 to extend out. The sealing filler 420 is filled between the gap and the stator coil 320 so that the sealing and partitioning assembly 400 divides the inner cavity into a first cavity 111 and a second cavity 112. The first air vent 120 is connected to the first cavity 111, and the second air vent 130 is connected to the second cavity 112.

[0024] In this embodiment, as Figure 1As shown, the rotating shaft 210 is a cylindrical structure, arranged horizontally along the axial direction of the motor. The axial direction of the rotating shaft 210 is horizontal, and it is the support and transmission component of the entire rotor. The inner fan 230 is a centrifugal or axial flow fan, which is fixed at both ends of the rotating shaft 210 at intervals along the axial direction of the rotating shaft 210. The blades of the inner fan 230 face the stator direction and can rotate synchronously with the rotating shaft 210. The rotor core 220 is an annular laminated structure, coaxially fixed on the rotating shaft 210, and located between the two inner fans 230. The outer circle of the rotor core 220 and the inner circle of the stator core 310 maintain a preset air gap to ensure the stability of the rotor during rotation. The positioning core is also a ring-shaped laminated structure, coaxially sleeved on the outside of the rotor core 220. Its axial length is adapted to the rotor core 220. The stator core 310 has a slot for the stator coil 320 to be embedded. The stator coil 320 can be formed by winding high-strength insulated wire. Its coil body is embedded in the slot of the stator core 310, and the coil ends at both ends extend axially out of the stator core 310, forming a structure with long extensions at both ends, which is adapted to the insulation and creepage distance requirements of the ultra-high voltage motor. The ends of the stator coil 320 and the housing 100 maintain a preset gap. The housing 100 is a hollow cylindrical structure with an inner cavity that houses the rotor and stator. The inner wall of the housing 100 is fixedly connected to the outer circumference of the stator core 310. A first air inlet 120 and a second air inlet 130 are provided on the outer wall of the housing 100. The first air inlet 120 serves as an air intake channel, evenly distributed along the circumference of the housing 100. Its location corresponds to the axial outer region of the inner fan 230's installation position, i.e., the side of the inner fan 230 away from the rotor core 220. The first air inlet 120 allows air to pass through... The housing 100 is provided with two sets of axially spaced air vents, each set being evenly distributed along the circumference of the housing 100. These two sets are respectively located in the axially outer region of the inner fan 230 to ensure that the airflow range of the first air vent 120 corresponds to that of the inner fan 230. The second air vent 130 is an air outlet channel, located in the region corresponding to the installation position of the stator core 310, that is, it is axially located between the two sets of first air vents 120. The second air vent 130 is also evenly distributed along the circumference of the housing 100, and the second air vent 130 is connected to the heat dissipation area of ​​the stator core 310.

[0025] A sealing and partitioning assembly 400 is installed in the radial gap between the rotating shaft 210 and the side wall of the housing to divide the inner cavity of the housing 100 and prevent air leakage. It includes a first partition 410, a second partition 430, and a sealing filler 420. The first partition 410 is fixed between the stator coil 320 and the side wall of the housing 100, and the second partition 430 is fixed between the stator coil 320 and the inner fan 230. A gap exists between the first partition 410 and the second partition 430, through which the end of the stator coil 320 can protrude. The protruding length is at least one-third of the length of the stator core 310. After the end of 0 extends out of the gap, a sealing filler 420 is filled in the gap between the gap and the stator coil 320, thereby further blocking the air path. The sealing separator is provided with two sets corresponding to the two internal fans 230 respectively, so that the sealing separator divides the inner cavity of the housing 100 into a first cavity 111, a second cavity 112 and a third cavity 111 along the axial direction. The end of the stator coil 320 is located in the first cavity 111, and the rotor core 220, the stator core 310 and part of the tail end of the stator coil 320 are located in the second cavity 112. The first cavity 111 is connected to the first air outlet 120, and the second cavity 112 is connected to the second air outlet 130.

[0026] In actual operation, when the motor starts, the shaft 210 drives the two internal fans 230 to rotate synchronously at high speed. The negative pressure generated by the internal fans 230 causes external cooling air (such as room temperature air or cooling medium) to enter the first cavity 111 through the first air inlet 120 on the side wall of the housing 100. At this time, the first cavity 111 becomes an independent air intake buffer area due to the isolation of the sealing and separating component 400. The cooling air gathers here and forms a stable airflow. The cooling air also performs heat exchange on the ends of the stator coil 320, carrying away the heat generated by the ultra-high voltage operation of the coil ends, thus providing heat for the stator coil. Cooling is provided at the end of the sub-coil 320. Then, under the air pressure of the internal fan 230, the cooling air in the first cavity 111 passes through the blades of the internal fan 230 and is guided to the second cavity 112. The cooling air flows to the stator core 310, passes through the ventilation slots or surface of the stator core 310, and exchanges heat with the stator core 310, carrying away the heat generated by core losses. The cooling air that has completed the heat exchange is discharged from the inner cavity of the housing 100 through the second air outlet 130 corresponding to the stator core 310 under the action of air pressure difference, realizing the unidirectional flow of cooling air. During motor operation, the internal fan 230 rotates continuously, and the external cooling air circulates continuously through the path of the first air outlet 120-first cavity 111-internal fan 230-second cavity 112-second air outlet 130, forming a stable directional cooling air path to ensure that the temperature of the stator end and the core is always controlled within a safe range.

[0027] In the above structure, the airflow isolation is achieved through the sealing and separating component 400, and the end of the stator coil 320 extends through the gap between the first separator 410 and the second separator 430, and is further sealed and filled by the sealing filler 420, thereby reducing the axial space occupied, meeting the space constraints of the ultra-high voltage motor, and meeting the motor frame length control requirements, ensuring that the deflection and critical speed meet the standards. It can also provide targeted heat dissipation for the end of the stator coil 320, avoiding the risk of overheating at the stator end of the ultra-high voltage motor and extending the service life of the motor. At the same time, the sealing filler 420 fills the gap between the first separator 410 and the second separator 430, preventing cooling air leakage and directing the cooling air to flow through the stator core 310, effectively reducing heat dissipation efficiency loss and improving heat dissipation efficiency. In addition, the first separator 410 and the second separator 430 respectively limit the radial movement of the stator coil 320 end, and together with the sealing filler 420 to wrap and fill the coil end, they form a limiting and fixing effect on the coil end, effectively limiting the radial vibration of the coil end, avoiding insulation wear or structural fatigue caused by the vibration of the coil, and improving the safety and stability of motor operation. In the specific structure of the first separator 410, the first separator 410 includes a first ring plate 411 and a second ring plate 412. The side wall of the housing 100 is provided with a radially extending mounting portion 161. The outer circular end of the first ring plate 411 is fixedly connected to the mounting portion 161, and the inner circular end of the first ring plate 411 is fitted and fixed to the outer circular end of the second ring plate 412. The inner circular end of the second ring plate 412 is in contact with the stator coil 320. The first ring plate 411 is connected to the mounting portion 161 by bolts, and a gasket 413 is provided between the first ring plate 411 and the mounting portion 161.

[0028] In this embodiment, as Figure 1 , Figure 2As shown, the first ring plate 411 is a circular plate structure. Its outer diameter matches the radial dimension of the mounting part 161 on the side wall of the housing 100, and its inner diameter matches the outer diameter of the second ring plate 412. Its plate thickness is determined according to the overall strength requirements of the motor. Multiple bolt holes are evenly opened on the first ring plate 411 along the circumferential direction. The diameter and number of these bolt holes correspond to the bolt holes on the mounting part 161 to achieve a fixed connection between the first ring plate 411 and the mounting part 161. The second ring plate 412 is also a circular plate structure, made of a material with excellent insulation properties and high temperature resistance, such as polyimide resin board or epoxy glass cloth board. Its outer diameter matches the inner diameter of the first ring plate 411, and its outer diameter can be larger than the inner diameter of the first ring plate 411. Therefore, when the first ring plate 411 and the second ring plate 412 are connected, there is an overlapping and contacting area between them, improving the stability of the connection. The inner diameter of the second ring plate 412 is adapted to the outer circumference of the stator coil 320 to ensure that the inner circular end of the second ring plate 412 is in contact with the stator coil 320. The mounting part 161 can be an integrated structure of the side wall of the housing 100, forming an annular protrusion extending radially inward along the housing 100. The mounting part 161 has bolt holes corresponding to the first ring plate 411. The gasket 413 is made of an elastic insulating material, such as silicone rubber or nitrile rubber.

[0029] In the connection between the first ring plate 411 and the mounting part 161, the gasket 413 is first fixed in the corresponding position of the mounting part 161, then the first ring plate 411 is placed over the gasket 413, making the bolt holes of the first ring plate 411 coaxial with the bolt holes of the gasket 413 and the mounting part 161. Finally, the bolts are passed through the bolt holes of the first ring plate 411 and the mounting part 161 in sequence to achieve a fixed connection between the first ring plate 411 and the mounting part 161, and the gasket 413 is tightly clamped between the first ring plate 411 and the mounting part 161 to form a sealing surface. In the connection between the first ring plate 411 and the second ring plate 412, the two are fixed by adhesive or bolt connection. The inner circular end face of the second ring plate 412 is polished to ensure a smooth and flat surface. After assembly, its inner circular end fits tightly against the outer circumferential surface of the stator coil 320 end without any obvious gaps. This achieves both radial positioning of the stator coil 320 and avoids damage to the coil insulation layer due to friction.

[0030] In the above structure, the first separator 410 adopts a split structure of a first ring plate 411 and a second ring plate 412. Compared with an integrated structure, by replacing the first ring plate 411 with different outer diameters, it can be adapted to housings 100 of different sizes; by replacing the second ring plate 412 with different inner diameters, it can be adapted to stator coils 320 of different specifications. This allows it to be adapted to ultra-high voltage motors of different power and voltage levels, reducing design and manufacturing costs and improving product versatility. At the same time, the bolt connection method facilitates installation and disassembly. If the separator needs to be replaced for motor maintenance in the future, only the bolts need to be removed, which is simple to operate and reduces maintenance time.

[0031] In the connection structure of the first ring plate 411 and the second ring plate 412, the first ring plate 411 and the second ring plate 412 are provided with binding holes at the joint. The first ring plate 411 and the second ring plate 412 are fixed by passing a binding rope through the binding holes, and polysulfone felt is filled in the gap between the first ring plate 411 and the second ring plate 412.

[0032] In this embodiment, binding holes are provided along their respective circumferential directions on the inner circular end face of the first ring plate 411 and the outer circular end face of the second ring plate 412, i.e., on the surfaces where the first ring plate 411 and the second ring plate 412 are in contact. This ensures that when the first ring plate 411 and the second ring plate 412 are in contact, their respective binding holes correspond to each other. The binding rope is made of a high-strength, high-temperature resistant, and excellent insulating material, such as fiberglass rope or aramid fiber rope. The first ring plate 411 and the second ring plate 412 are aligned and fitted together, making the binding holes coaxial. Then, one end of the binding rope is passed through a set of aligned binding holes, and the first ring plate 411 and the second ring plate 412 are fixed by cross-binding or circular wrapping. A high-temperature resistant insulating adhesive, such as silicone adhesive, is used to cure the knot to prevent it from loosening and to avoid wear caused by friction between the rope end and other components. The binding rope secures the first ring plate 411 and the second ring plate 412 in a circumferential direction through multiple sets of binding holes, effectively resisting the radial impact force and axial tension during motor operation, and preventing relative displacement or separation between the first ring plate 411 and the second ring plate 412.

[0033] Furthermore, before the first ring plate 411 and the second ring plate 412 are bonded together, the cut polysulfone felt is evenly laid on the inner circular end face of the first ring plate 411 (or the outer circular end face of the second ring plate 412), covering the entire area of ​​the bonding surface to ensure no gaps. Then, the second ring plate 412 is bonded to the first ring plate 411, and the tension of the binding ropes tightly compresses the polysulfone felt into the gap between the two, completely filling the gap without displacement or damage due to compression. The polysulfone felt filling the bonding gap between the first ring plate 411 and the second ring plate 412, with its elastic properties, can fully fill the tiny gaps within, further blocking the cooling air leakage channel between the first cavity 111 and the second cavity 112.

[0034] In addition, a stator pressure ring 311 is provided on the stator core 310 along its circumference. A support screw 330 extending axially is fixedly connected to the stator pressure ring 311. The end of the support screw 330 away from the stator pressure ring 311 is connected to the second ring plate 412. The second ring plate 412 is provided with a U-shaped slot 414. One end of the support screw 330 passes through the U-shaped slot 414, and the second ring plate 412 and the support screw 330 are tightly connected by a polyester fiberglass rope.

[0035] In this embodiment, the stator pressure ring 311 is an annular component, the inner diameter of which is adapted to the outer diameter of the stator core 310. The stator pressure ring 311 is provided with multiple threaded holes along the circumferential direction. The threaded holes are connected to the support screw 330. One end of the support screw 330 is fixedly connected to the stator pressure ring 311 and extends along the axial direction of the housing 100. The other end is connected to the second ring plate 412. A U-shaped slot 414 is opened on the second ring plate 412 along the circumferential direction corresponding to the position of the support screw 330. The U-shaped slot 414 extends to the outer circle. When connected, the support screw 330 is placed in the U-shaped slot 414. The polyester-glass rope is made of high-strength polyester-glass rope (made of polyester fiber and glass fiber blend). First, the end of the support screw 330 is placed into the U-shaped slot of the second ring plate 412. The position of the second ring plate 412 is adjusted so that the ring plate is horizontal and tightly attached to the stator coil 320. Then, the polyester-glass rope is wrapped around the connection between the support screw 330 and the second ring plate 412 and tightly bound together by figure-eight winding or double-strand cross binding. Finally, knots are tied at both ends of the polyester-glass rope, and the knots are cured with a high-temperature resistant insulating adhesive (such as epoxy adhesive) to prevent the knots from loosening and to avoid friction and wear between the rope ends and other parts.

[0036] The rigid connection between the stator pressure ring 311 and the support screw 330 provides reliable axial support for the second ring plate 412, effectively resisting the axial force caused by the wind pressure and stator coil 320 vibration generated by the internal fan 230 during motor operation, and preventing axial displacement or deformation of the second ring plate 412. The U-shaped slotted structure of the second ring plate 412 can compensate for the radial error of the support screw 330 during installation within a certain range, reducing the assembly accuracy requirements.

[0037] In the specific structure of the sealing filler 420, the sealing filler 420 includes a thermally expandable glass felt and a sealant. In this embodiment, the thermally expandable glass felt uses high-temperature resistant glass fiber (such as alkali-free glass fiber) as the base material, and uniformly mixes thermally expandable microspheres (the main component is a thermoplastic resin shell encapsulating a low-boiling-point solvent) inside. It is needle-punched to form a flexible felt-like structure, and its volume expansion rate after heating can reach 100%-300%, while maintaining good insulation performance and elasticity after expansion. The sealant can be a high-temperature resistant insulating sealant, such as epoxy-modified silicone sealant or organosilicon sealant, which has excellent high-temperature resistance, insulation performance and bonding strength, and has a certain elasticity after curing, which can adapt to the vibration and temperature changes during motor operation.

[0038] The cut thermally expandable glass felt is tightly adhered to the inner wall of the gap between the first separator 410 and the second separator 430 or to the outer circumferential surface of the stator coil 320, ensuring that there are no obvious gaps between the felt and the gap wall or the coil surface. The uniformly mixed sealant is then evenly filled into the tiny gaps between the thermally expandable glass felt and the gap wall or the stator coil 320 using a syringe or scraper. Subsequently, the entire motor is placed in a constant temperature environment of 80°C for preheating treatment. This accelerates the initial curing of the sealant and causes the thermally expandable glass felt to expand due to heat, increasing its volume and compressing the sealant, forcing the sealant to further fill the tiny gaps. After preheating, the motor is cooled to room temperature, and the sealant continues to cure until it is fully set. The thermally expandable glass felt maintains a stable shape after expansion and is tightly bonded to the cured sealant, completely filling all gaps between the first separator 410, the second separator 430, and the stator coil 320, achieving a leak-free seal.

[0039] In the specific structure of the second separator 430, the second separator 430 includes an insulating sleeve, which is fixed to the inner circle of the stator coil 320, and the outer end face of the insulating sleeve is in contact with the stator coil 320. The insulating sleeve covers the inner fan 230. The insulating sleeve is fixedly connected to the stator coil 320 by a polyester fiberglass rope.

[0040] In this embodiment, the insulating sleeve is made of high-strength, high-temperature resistant insulating material, such as epoxy glass cloth tube or polyimide resin tube, which has excellent insulation performance and structural stability. It can also withstand the wind pressure generated by the rotation of the inner fan 230 and the temperature fluctuations during motor operation. The insulating sleeve has a cylindrical tubular structure, and its inner diameter is determined according to the outer diameter of the inner fan 230. The outer diameter is adapted to the inner diameter of the stator coil 320, so that the outer circle of the sleeve can fit tightly against the inner circle of the stator coil 320. High-strength polyester-glass rope is selected. 3-4 sets of annular grooves are opened axially at intervals on the outer surface of the insulating sleeve. The groove width is adapted to the diameter of the polyester-glass rope to prevent slippage during binding. The polyester-glass rope is wrapped around the annular groove on the outer circle of the insulating sleeve and the outer circumference of the stator coil 320, and a spiral winding binding method is used to ensure that the insulating sleeve and the stator coil 320 are tightly fixed. Finally, knots are tied at both ends of the polyester-glass rope, and the knots are cured with high-temperature resistant insulating adhesive to prevent the knots from loosening and to avoid friction and wear between the rope ends and other components.

[0041] The insulating sleeve houses the inner fan 230, forming an annular airflow channel. This guides the cooling air generated by the inner fan 230 to flow directionally along the inner wall of the sleeve towards the stator core 310, preventing the cooling air from dispersing and leaking due to lack of guidance. Simultaneously, the tight fit between the outer circumference of the sleeve and the inner circumference of the stator coil 320 blocks the path of cooling air leakage from the gaps in the inner circumference of the coil. The insulating sleeve is tightly fixed to the stator coil 320 by a polyester fiberglass rope, providing radial restraint to the stator coil 320 from the inner circumference direction. This effectively prevents insulation wear or structural fatigue of the stator coil 320 due to vibration, extending the coil's service life.

[0042] In the specific structure of the housing 100, the housing 100 includes a front cover plate 140, a rear cover plate 150, a top plate 160, a front bearing mechanism 171, and a rear bearing mechanism 172. The front cover plate 140 is fixedly connected to the front bearing mechanism 171, and the front bearing mechanism 171 is connected to the rotating shaft 210. The rear cover plate 150 is fixedly connected to the rear bearing mechanism 172, and the rear bearing mechanism 172 is connected to the rotating shaft 210. The top plate 160 is fixedly connected to the front cover plate 140 and the rear cover plate 150 to form an inner cavity. The top plate 160 is provided with a first air vent 120 and a second air vent 130.

[0043] In this embodiment, both the front cover plate 140 and the rear cover plate 150 are circular plate-shaped components. Bearing mounting holes are provided in the center of both the front cover plate 140 and the rear cover plate 150. The top plate 160 is a cylindrical structure. A first air vent 120 and a second air vent 130 are provided on the side wall of the top plate 160. Flanges are provided at both ends of the top plate 160, corresponding to the front cover plate 140 and the rear cover plate 150 respectively. Both the front bearing mechanism 171 and the rear bearing mechanism 172 consist of a bearing housing, a rolling bearing, and a sealing cover. The bearing housing of the front bearing mechanism 171 is press-fitted into the central mounting hole of the front cover plate 140, and the end face of the bearing housing is fastened to the inner side of the cover plate with bolts. The assembly method of the rear bearing mechanism 172 is exactly the same as that of the rear cover plate 150. One end of the rotating shaft 210 passes through the bearing mechanism of the front cover plate 140, and the other end passes through the bearing mechanism of the rear cover plate 150. The bearings achieve radial and axial positioning of the rotating shaft 210.

[0044] In the embodiments disclosed in this application, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linking" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments disclosed in this application according to the specific circumstances.

[0045] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A cooling structure for the stator end of an ultra-high voltage motor, characterized in that, include: A rotor includes a shaft and a rotor core, wherein two internal fans are spaced apart along the axial direction on the shaft, and the rotor core is disposed between the two internal fans; The stator includes the stator core and the stator coils; The housing has an inner cavity that houses the rotor and stator. The side wall of the housing away from the rotating shaft has at least a first air vent and a second air vent. The first air vent corresponds to the axial outer region of the inner fan, and the second air vent is corresponding to the stator core. A sealing and partitioning assembly includes a first partition, a sealing filler, and a second partition. The first partition is disposed between the stator coil and the side wall of the housing, and the second partition is disposed between the stator coil and the internal fan. A gap exists between the first partition and the second partition for the stator coil to extend out. The sealing filler is filled between the gap and the stator coil so that the sealing and partitioning assembly divides the inner cavity into a first cavity and a second cavity. The first air outlet communicates with the first cavity, and the second air outlet communicates with the second cavity.

2. The ultra-high voltage motor stator end airflow cooling structure according to claim 1, characterized in that, The first separator includes a first ring plate and a second ring plate. The side wall of the housing is provided with a mounting portion extending radially. The outer circular end of the first ring plate is fixedly connected to the mounting portion. The inner circular end of the first ring plate is fitted and fixed to the outer circular end of the second ring plate. The inner circular end of the second ring plate is in contact with the stator coil.

3. The ultra-high voltage motor stator end airflow cooling structure according to claim 2, characterized in that, Both the first ring plate and the second ring plate have binding holes at their joints. The first ring plate and the second ring plate are fixed by passing a binding rope through the binding holes, and polysulfone felt is filled in the gap between the first ring plate and the second ring plate.

4. The ultra-high voltage motor stator end airflow cooling structure according to claim 2, characterized in that, The stator core is provided with a stator pressure ring along its circumference, and a support screw extending axially is fixedly connected to the stator pressure ring. The end of the support screw away from the stator pressure ring is connected to the second ring plate.

5. The ultra-high voltage motor stator end airflow cooling structure according to claim 4, characterized in that, The second ring plate has a U-shaped slot, one end of the support screw passes through the U-shaped slot, and the second ring plate and the support screw are tightly connected by a polyester fiberglass rope.

6. The ultra-high voltage motor stator end airflow cooling structure according to claim 2, characterized in that, The first ring plate is connected to the mounting part by bolts, and a gasket is provided between the first ring plate and the mounting part.

7. The ultra-high voltage motor stator end airflow cooling structure according to claim 1, characterized in that, The sealing filler includes thermally expandable glass mat and sealant.

8. The ultra-high voltage motor stator end airflow cooling structure according to claim 1, characterized in that, The second separator includes an insulating sleeve, which is fixed to the inner circle of the stator coil and the outer end face of the insulating sleeve is in contact with the stator coil. The insulating sleeve covers the inner fan.

9. The ultra-high voltage motor stator end airflow cooling structure according to claim 8, characterized in that, The insulating sleeve is fixedly connected to the stator coil by a polyester fiberglass rope.

10. The ultra-high voltage motor stator end airflow cooling structure according to claim 1, characterized in that, The housing includes a front cover plate, a rear cover plate, a top plate, a front bearing mechanism, and a rear bearing mechanism. The front cover plate is fixedly connected to the front bearing mechanism, and the front bearing mechanism is connected to the rotating shaft. The rear cover plate is fixedly connected to the rear bearing mechanism, and the rear bearing mechanism is connected to the rotating shaft. The top plate is fixedly connected to the front cover plate and the rear cover plate to form the inner cavity. The top plate is provided with a first air vent and a second air vent.

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