Cooling and heat dissipation structure for rotor core of switched reluctance motor
By designing the spiral cooling channel and cooling channel on the rotor core of the switched reluctance motor, the cooling channel on the support wall is solved, and the problems of oil agitation and heat dissipation caused by oil accumulation in the hollow shaft oil injection cooling technology are achieved, and a more efficient cooling and heat dissipation effect is achieved.
Patent Information
- Application Number
- CN202411972721.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-11
AI Technical Summary
When the rotor core of the switched reluctance motor with high speed and high power density is used to use the hollow shaft oil injection cooling technology, the oil gathers in the concave surface of the convex electrode structure, resulting in increased oil agitation loss and difficult heat to dissipate, which can easily cause the core to demagnetize at high temperature.
A cooling and heat dissipation structure of the rotor core of the switched reluctance motor is designed, and the cooling flow path is constructed using the spiral cooling channel on the outer wall of the inner cylinder, the cooling inflow channel and the cooling outflow channel on the support wall. The cooling oil flows spirally along the spiral cooling channel, taking away the heat of the rotor core.
By constructing a cooling flow path from the inside, the direct injection of cooling oil into the end of the rotor core is avoided, the oil agitation loss is reduced, the efficiency of heat dissipation is improved, and the high-temperature demagnetization of the core is avoided.
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Figure CN119813626A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the technical field of cooling and heat dissipation design of switched reluctance motors, and specifically relates to a cooling and heat dissipation structure of a rotor core of a switched reluctance motor. Background Art
[0002] The switched reluctance motor has the advantages of simple structure, low cost and high speed, and has great application potential in aviation equipment.
[0003] The working principle of the switched reluctance motor is based on the principle of minimum reluctance, that is, the magnetic flux always closes along the path with the minimum reluctance, and the tangential magnetic pull generated by the distortion of the magnetic field forms a torque. Compared with the general permanent magnet motor, the stator and rotor of the switched reluctance motor both adopt a double salient pole structure, and the number of stator and rotor poles is different. The special structure of the rotor, on the one hand, will make the alternating amplitude of the magnetic field density inside the switched reluctance motor larger, and on the other hand, it will decompose more harmonic components in the air gap, which will cause a large amount of eddy current loss inside the permanent magnet. When the heat cannot be discharged in time, it will cause the permanent magnet to demagnetize and cause failure.
[0004] At present, for general high-power density smooth rotor permanent magnet motors, the heat dissipation of the rotor mostly adopts the technical solution of hollow shaft oil injection. A spray hole is opened at a position corresponding to the end of the rotor on the hollow shaft. When the rotor rotates at high speed, the cooling oil is sprayed out from the spray hole at a high speed, flushing the end of the rotor and taking away the heat generated by the iron core, thereby achieving the purpose of cooling the iron core.
[0005] The high-speed, high-power density switched reluctance motor can reach a speed of 16474r / min and a power density capacity of 250kVA. If the hollow shaft oil injection technology is used to cool the salient pole rotor, some oil will gather in the concave surface of the rotor core, resulting in large oil stirring losses, causing heat to accumulate on the surface of the core and difficult to dissipate, which can easily cause high-temperature demagnetization of the core.
[0006] This application is proposed in view of the above-mentioned technical defects. Summary of the invention
[0007] The purpose of the present application is to provide a cooling and heat dissipation structure for a rotor core of a switched reluctance motor, so as to overcome or alleviate at least one aspect of the known technical defects.
[0008] The technical solution of this application is:
[0009] A cooling and heat dissipation structure for a rotor core of a switched reluctance motor, comprising a rotor core, an inner cylinder, and a rotating shaft;
[0010] The rotor core is sleeved on the outer periphery of the inner cylinder, and the outer wall of the inner cylinder has multiple spiral cooling channels;
[0011] The rotating shaft is a hollow shaft, which passes through the inner cylinder and is connected to the inner wall of the inner cylinder through a plurality of supporting walls to form a bracket structure;
[0012] A baffle is provided inside the rotating shaft, dividing the rotating shaft into a cooling inlet flow chamber and a cooling outlet flow chamber, wherein the inlet of the cooling inlet flow chamber is at one end of the rotating shaft, and the outlet of the cooling outlet flow chamber is at the other end of the rotating shaft;
[0013] Each support wall is provided with a cooling inlet channel and a cooling outlet channel. The cooling inlet channel on each support wall connects each spiral cooling channel with the cooling inlet cavity, and the cooling outlet channel connects each spiral cooling channel with the cooling outlet cavity.
[0014] According to at least one embodiment of the present application, in the above-mentioned switched reluctance motor rotor core cooling and heat dissipation structure, the inner cylinder, the rotating shaft, and the supporting wall are an integrally formed structure.
[0015] According to at least one embodiment of the present application, in the above-mentioned switched reluctance motor rotor core cooling and heat dissipation structure, the number of spiral cooling channels and their supporting walls on the outer wall of the inner cylinder is four, and the four supporting walls are distributed at 90° intervals.
[0016] According to at least one embodiment of the present application, in the above-mentioned switched reluctance motor rotor core cooling and heat dissipation structure, the width of each spiral cooling channel is 9 mm;
[0017] The depth of each spiral cooling channel is 1 / 2 to 1 / 3 of the wall thickness of the inner tube.
[0018] According to at least one embodiment of the present application, in the above-mentioned switched reluctance motor rotor core cooling and heat dissipation structure, the cross-section of each spiral cooling channel is rectangular, semicircular or trapezoidal.
[0019] According to at least one embodiment of the present application, in the above-mentioned switched reluctance motor rotor core cooling and heat dissipation structure, the bottom wall of each spiral cooling channel has a small-sized spiral groove, or the bottom wall of the spiral cooling channel is corrugated, or has transverse stripes.
[0020] This application has at least the following beneficial technical effects:
[0021] A cooling and heat dissipation structure for a rotor core of a switched reluctance motor is provided, a cooling flow path is constructed, and the rotor core is cooled and dissipated from the inside, so that cooling oil is not sprayed directly to the end of the rotor core, so that oil is gathered in the concave surface of the rotor core, resulting in large oil stirring loss, causing heat to accumulate on the surface of the rotor core and difficult to dissipate, causing the problem of high-temperature demagnetization of the rotor core. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 is a schematic diagram of a cooling and heat dissipation structure of a rotor core of a switched reluctance motor provided in an embodiment of the present application;
[0023] Figure 2 It is a schematic diagram of the combination of the rotating shaft, the inner cylinder, and the supporting wall provided in the embodiment of the present application;
[0024] Figure 3 is a schematic diagram of a cooling flow path provided in an embodiment of the present application at an angle;
[0025] Figure 4 is a schematic diagram of a cooling flow path provided in an embodiment of the present application from another angle;
[0026] in:
[0027] 1- rotor core; 2- inner cylinder; 3- rotating shaft; 4- supporting wall;
[0028] A- spiral cooling channel; B- cooling inlet cavity; C- cooling outlet cavity; D- cooling inlet channel; E- cooling outlet channel.
[0029] In order to better illustrate the present embodiment, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. In addition, the drawings are only used for illustrative purposes and should not be construed as limitations on the present application. DETAILED DESCRIPTION
[0030] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.
[0031] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.
[0032] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.
[0033] A cooling and heat dissipation structure for the rotor core of a switched reluctance motor, such as Figure 1 As shown, it includes a rotor core 1, an inner cylinder 2, and a rotating shaft 3.
[0034] The rotor core 1 is sleeved on the outer periphery of the inner cylinder 2, and the outer wall of the inner cylinder 2 has a plurality of spiral cooling channels A.
[0035] The rotating shaft 3 is a hollow shaft, which passes through the inner cylinder 2 and is connected to the inner wall of the inner cylinder 2 through a plurality of supporting walls 4 to form a support structure. Figure 2 shown.
[0036] The rotating shaft 3 is provided with a baffle plate, which divides the rotating shaft 3 into a cooling inlet flow chamber B and a cooling outlet flow chamber C. The inlet of the cooling inlet flow chamber B is at one end of the rotating shaft 3, and the outlet of the cooling outlet flow chamber C is at the other end of the rotating shaft 3.
[0037] Each support wall 4 has a cooling inlet channel D and a cooling outlet channel E. The cooling inlet channel D on each support wall 4 connects each spiral cooling channel A with the cooling inlet cavity B, and the cooling outlet channel E connects each spiral cooling channel A with the cooling outlet cavity C.
[0038] In the cooling and heat dissipation structure of the switched reluctance motor rotor core disclosed in the above embodiment, a cooling flow path is constructed by using a cooling inlet flow cavity B in the rotating shaft 3, a cooling inlet flow channel D in the supporting wall 4, a spiral cooling channel A on the outer wall of the inner cylinder 2, a cooling outlet flow channel E in the supporting wall 4, and a cooling outlet flow cavity C in the rotating shaft 3, such as Figure 3-Figure 4 As shown, in specific applications, cooling oil can be introduced into the cooling inlet cavity B from the inlet at the end of the rotating shaft 3. The cooling oil then enters each spiral cooling channel A through each cooling inlet channel D under the action of centrifugal force, flows in a spiral along the spiral cooling channel A, takes away the heat of the rotor core 1 along the way, cools the rotor core 1, and then flows into the cooling outlet cavity C through each cooling outlet channel E, and flows out from the outlet at the end of the rotating shaft 3.
[0039] The cooling and heat dissipation structure of the switched reluctance motor rotor core disclosed in the above-mentioned embodiment constructs a cooling flow path to cool the rotor core 1 from the inside, thereby avoiding directly spraying cooling oil to the end of the rotor core 1, causing the oil to gather in the concave surface of the rotor core 1, resulting in large oil stirring losses, causing heat to accumulate on the surface of the rotor core 1 and difficult to dissipate, causing the problem of high-temperature demagnetization of the rotor core 1.
[0040] In the cooling and heat dissipation structure of the switched reluctance motor rotor core disclosed in the above embodiment, since the cooling oil flows spirally along the spiral cooling channel A and the shaft 3 rotates at high speed, the cooling oil has an extremely high convection heat transfer capacity for the rotor core 1, which is much higher than the general forced convection heat transfer, and can effectively ensure the cooling and heat dissipation effect of the rotor core 1. In addition, the design adopts multiple parallel flow channels, which can effectively reduce the local resistance loss caused by the inlet and outlet of the end of the shaft 1 and reduce the power consumption of the external pump.
[0041] The inner tube 2, the rotating shaft 3 and the supporting wall 4 are an integrally formed structure. In addition, considering the structural size and weight, the number of the spiral cooling channels A and the supporting walls 4 on the outer wall of the inner tube 2 is designed to be four, and the four supporting walls 4 are distributed at 90° intervals.
[0042] With the help of CFD fluid simulation analysis software, it is found that the wider the size of the spiral cooling channel A on the outer wall of the inner tube 2, the smaller the coolant flow resistance, the larger the contact area with the inner side of the rotor core 1, and the better the cooling and heat dissipation effect of the rotor core 1. However, the distribution density of the spiral cooling channel A will increase, the processing difficulty will increase, the strength of the inner tube 2 will be reduced, and the spiral cooling channel A will be distributed close to the edge of the inner tube 2, making it difficult to ensure a reliable sealing effect and prone to cooling oil leakage. Taking all factors into consideration, the width of the spiral cooling channel A is designed to be 9 mm.
[0043] In order to ensure the strength of the inner tube 2 and the flow resistance of the coolant, the depth of the spiral cooling channel A on the outer wall of the inner tube 2 is designed to be 1 / 3 to 1 / 2 of the wall thickness of the inner tube 2.
[0044] In order to facilitate processing, the cross-section of the spiral cooling channel A on the outer wall of the inner tube 2 can be designed to be rectangular, or semicircular or trapezoidal. In addition, in order to enhance the cooling and heat dissipation effect of the coolant on the rotor core 1, the bottom wall of the spiral cooling channel A can be further designed to have a small-sized spiral groove, or the bottom wall of the spiral cooling channel A can be designed to be corrugated, or have transverse stripes.
[0045] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.
Claims
1. A cooling and heat dissipation structure for a switched reluctance motor rotor core, characterized in that: It comprises a rotor core (1), an inner cylinder (2), and a rotating shaft (3); The rotor core (1) is sleeved on the outer periphery of the inner cylinder (2), and the outer wall of the inner cylinder (2) has a plurality of spiral cooling channels (A); The rotating shaft (3) is a hollow shaft, which passes through the inner cylinder (2) and is connected to the inner wall of the inner cylinder (2) via a plurality of supporting walls (4) to form a support structure. A baffle is provided inside the rotating shaft (3), dividing the rotating shaft (3) into a cooling inlet chamber (B) and a cooling outlet chamber (C); the inlet of the cooling inlet chamber (B) is at one end of the rotating shaft (3), and the outlet of the cooling outlet chamber (C) is at the other end of the rotating shaft (3); Each support wall (4) is provided with a cooling inlet channel (D) and a cooling outlet channel (E); the cooling inlet channel (D) on each support wall (4) connects each spiral cooling channel (A) with the cooling inlet cavity (B), and the cooling outlet channel (E) connects each spiral cooling channel (A) with the cooling outlet cavity (C).
2. The cooling and heat dissipation structure of the switched reluctance motor rotor core according to claim 1, characterized in that: The inner cylinder (2), the rotating shaft (3) and the supporting wall (4) are an integrally formed structure.
3. The cooling and heat dissipation structure of the switched reluctance motor rotor core according to claim 2, characterized in that: The number of the spiral cooling channel (A) and its supporting walls (4) on the outer wall of the inner tube (2) is four, and the four supporting walls (4) are distributed at 90° intervals.
4. The cooling and heat dissipation structure of the switched reluctance motor rotor core according to claim 3, characterized in that: The width of each spiral cooling channel (A) is 9 mm; The depth of each spiral cooling channel (A) is 1 / 2 to 1 / 3 of the wall thickness of the inner tube (2).
5. The switched reluctance motor rotor core cooling and heat dissipation structure according to claim 4, characterized in that: The cross section of each spiral cooling channel (A) is rectangular, semicircular or trapezoidal.
6. The cooling and heat dissipation structure of the rotor core of the switched reluctance motor according to claim 5, characterized in that: The bottom wall of each spiral cooling channel (A) has a small-sized spiral groove, or the bottom wall of the spiral cooling channel (A) is corrugated, or has transverse stripes.