WIND POWER GENERATOR SET, ELECTROMAGNETIC DEVICE, AND HEAT EXCHANGE OR DRYING DEVICE FOR IRON CORE
20210025371 ยท 2021-01-28
Assignee
Inventors
Cpc classification
H02K2203/09
ELECTRICITY
H02K7/1838
ELECTRICITY
H02K15/125
ELECTRICITY
F03D9/25
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D80/60
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
H02K9/08
ELECTRICITY
Y02E10/72
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H02K3/50
ELECTRICITY
International classification
F03D80/60
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F03D9/25
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
H02K3/24
ELECTRICITY
H02K3/50
ELECTRICITY
Abstract
A wind power generator set, an electromagnetic device and a heat exchange or drying device for an iron core. The heat exchange or drying device for an iron core includes a sprayer capable of feeding an airflow, wherein the sprayer is provided with a spraying hole, and the airflow can be sprayed to an end of the iron core through the spraying hole. The sprayer sprays a cold airflow or a hot airflow at the end of the iron core, creating a cooling and drying environment at the end of the iron core. This facilitates the heat dissipation of the iron core and also the maintenance of the insulation performance of an end of a winding, including the insulation of the winding itself and the insulation between the winding and the iron core, and also the protection of a magnetic pole and a protective covering layer thereof.
Claims
1. A heat exchange or drying device for an iron core, comprising a sprayer configured to introduce airflow, wherein the sprayer is provided with spray holes, and the airflow is allowed to be sprayed to an end portion of the iron core through the spray holes.
2. The heat exchange or drying device according to claim 1, wherein the sprayer comprises an annular spray pipe matching with an annular shape of the iron core, the annular spray pipe is provided at the end portion of the iron core, and the plurality of spray holes are provided in a circumferential direction of the annular spray pipe.
3. The heat exchange or drying device according to claim 2, wherein the annular spray pipe is mounted at an end face of the iron core.
4. The heat exchange or drying device according to claim 3, wherein windings are accommodated in slots of the iron core, the end face of the iron core is provided with an annular busbar, and connectors of the windings are connected to the busbar; and the annular spray pipe is located at an inner side or an outer side of the busbar or is arranged to axially facing the busbar directly, and the annular spray pipe is configured to spray the airflow to the busbar.
5. The heat exchange or drying device according to claim 2, wherein windings are accommodated in slots of the iron core, the windings are wound at the end portion of the iron core to form winding end portions, and the annular spray pipe is inserted into a through hole formed by all the winding end portions at the end portion of the iron core.
6. The heat exchange or drying device according to claim 2, wherein two or more airflow inlets are evenly distributed at the annular spray pipe in a circumferential direction, and the airflow inlets are configured for introducing the airflow; and an airflow dividing pipe is arranged inside the annular spray pipe at a position corresponding to one of the airflow inlets, the introduced airflow is allowed to enter into the airflow dividing pipe first, and the airflow dividing pipe is configured to spray the airflow from two ends, to guide the airflow to flow in the circumferential direction of the annular spray pipe and then be sprayed out from the spray holes.
7. The heat exchange or drying device according to claim 2, wherein the spray holes are provided at an inner side of the annular spray pipe or both the inner side and an intermediate portion of the annular spray pipe, and no spray hole is provided at and an outer side of the annular spray pipe; and the spray holes are configured to spray in a radial direction and/or an axial direction of the iron core.
8. The heat exchange or drying device according to claim 1, wherein the iron core is provided with a plurality of first iron core fasteners configured for tensioning the iron core in an axial direction, a spray hole is arranged at an end portion of each of the first iron core fasteners, and the first iron core fasteners are embodied as the sprayer.
9. The heat exchange or drying device according to claim 8, wherein the first iron core fastener is provided with an airflow passage extending in the axial direction and running through at least one end of the first iron core fastener, the airflow entering into the airflow passage is sprayed at least from the end, and an end portion of the airflow passage configured to spray the airflow is the spray hole.
10. The heat exchange or drying device according to claim 9, wherein the first iron core fastener is a stud bolt, the airflow passage runs through the stud bolt, and the spray hole is a portion of the airflow passage located at a head of the stud bolt.
11. The heat exchange or drying device according to claim 9, wherein a side wall passage is further provided, the side wall passage runs through a side wall of the first iron core fastener to be in communication with the airflow passage, the airflow enters into the airflow passage through the side wall passage, and the airflow is introduced from the side wall passage.
12. The heat exchange or drying device according to claim 11, wherein the airflow passage axially runs through two ends of the first iron core fastener, and the airflow is sprayed out from two ends of the airflow passage.
13. The heat exchange or drying device according to claim 11, further comprising a recovery passage, wherein the airflow passage runs through one end of the first iron core fastener, and the recovery passage runs through another end of the first iron core fastener; and the side wall passage comprises an inlet passage and an outlet passage isolated from each other, the airflow is introduced into the airflow passage from the inlet passage and be sprayed out from the end portion of the airflow passage; the sprayed airflow is allowed to perform heat exchange outside and then enter from an end portion of the recovery passage, and flow out through the recovery passage and the outlet passage for recovery.
14. The heat exchange or drying device according to claim 12, wherein the airflow passage comprises a first passage and a second passage isolated from each other, one of the first passage and the second passage is configured to introduce cold airflow, and the other is configured to introduce hot airflow.
15. The heat exchange or drying device according to claim 14, wherein the heat exchange or drying device further comprises a vortex flow separator, the vortex flow separator comprises a jet pipe and a vortex flow separation pipe, the vortex flow separation pipe comprises a vortex flow chamber, and a cold end pipe section and a hot end pipe section which are located at two ends of the vortex flow chamber respectively; the jet pipe is in communication with the vortex flow chamber, compressed airflow is allowed to flow through the jet pipe to form spiral airflow, and the spiral airflow is allowed to flow into the vortex flow chamber in a tangential direction of the vortex flow chamber; a cross-sectional area of the cold end pipe section is smaller than a cross-sectional area of the vortex flow chamber, and a cross-sectional area of the hot end pipe section is equal to or greater than the cross-sectional area of the vortex flow chamber; a valve having a valve port is arranged inside the hot end pipe section, the valve has a conical surface, and after the spiral airflow is introduced into the vortex flow separation pipe, external airflow of the spiral airflow is allowed to flow toward the valve port, be gradually heated to become the hot airflow, and then flow out through the valve port; central airflow of the spiral airflow is allowed to pass by the conical surface of the valve and flow back, be cooled to be the cold airflow, and then flow out from the cold end pipe section; and the cold airflow and the hot airflow are allowed to be introduced into the first passage and the second passage, respectively.
16. The heat exchange or drying device according to claim 15, wherein the iron core (204) is fastened to an iron core support, the vortex flow separator is arranged at an inner side of the iron core support, the hot airflow or cold airflow from the vortex flow separator is allowed to flow into the side wall passage; and the side wall passage further runs through a side wall of the iron core support, inserts into the iron core and runs through the side wall of the first iron core fastener, to be in communication with the airflow passage.
17. The heat exchange or drying device according to claim 1, wherein the heat exchange or drying device further comprises a vortex flow separator, the vortex flow separator comprises a jet pipe and a vortex flow separation pipe, the vortex flow separation pipe comprises a vortex flow chamber, and a cold end pipe section and a hot end pipe section which are located at two ends of the vortex flow chamber respectively; the jet pipe is in communication with the vortex flow chamber, compressed airflow is allowed to flow through the jet pipe to form a spiral airflow, and the spiral airflow is allowed to flow into the vortex flow chamber in a tangential direction of the vortex flow chamber; a cross-sectional area of the cold end pipe section is smaller than a cross-sectional area of the vortex flow chamber, and a cross-sectional area of the hot end pipe section is equal to or greater than the cross-sectional area of the vortex flow chamber; a valve having a valve port is arranged inside the hot end pipe section, the valve has a conical surface, and after the spiral airflow is introduced into the vortex flow separation pipe, external airflow of the spiral airflow is allowed to flow toward the valve port, be gradually heated to become the hot airflow, and then flow out through the valve port; central airflow of the spiral airflow is allowed to pass by the conical surface of the valve and flow back, be cooled to be the cold airflow, and then flow out from the cold end pipe section; and the hot airflow or the cold airflow is the airflow introduced into the sprayer.
18. The heat exchange or drying device according to claim 17, wherein one end of the vortex flow chamber is provided with a through hole, a pipe body of the cold end pipe section is in communication with the through hole; the vortex flow chamber and the hot end pipe section are integrally formed and have equal diameters; the valve comprises a conical throttling member, a conical end of the throttling member is arranged to face the cold end pipe section, the throttling member is located at a central portion of the hot end pipe section, and an annular clearance formed between the throttling member and an inner wall of the hot end pipe section is embodied as the valve port; and an axis of the cold end pipe section coincides with an axis of the throttling member.
19. An electromagnetic device, comprising an iron core, wherein the electromagnetic device further comprises a heat exchange or drying device, and the heat exchange or drying device is the heat exchange or drying device according to claim 1.
20. A wind turbine, comprising a generator, the generator comprising an iron core, wherein the wind turbine further comprises the heat exchange or drying device according to claim 1.
21. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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REFERENCE NUMERALS IN FIGS. 1 to 7
[0053] 100 nacelle, 101 external circulation drive motor, [0054] 102 external circulation induced draft fan, [0055] 103 external circulation airflow discharge port, [0056] 104 inlet connecting section of external circulation induced draft fan; [0057] 201 internal circulation driving motor, 202 internal circulation induced draft fan, [0058] 203 internal circulation confluence chamber, [0059] 204 inlet connecting section of external circulation induced draft fan; [0060] 300 surface type heat exchanger; [0061] 400 internal circulation airflow drawing and conveying pipe, [0062] 500 generator, 500a cooling airflow inlet orifice plate, [0063] 500b inlet orifice; [0064] 600 rotor; [0065] 010 stacking sheet, 010a tooth portion, [0066] 010b open slot, 010b winding slot; [0067] 030 structural support, 040 cooling ventilation duct, [0068] 050 hot air drawing and confluence device, [0069] 060 confluence device, 070 confluence passage;
REFERENCE NUMERALS IN FIGS. 8 to 28:
[0070] 200 generator, 201 magnetic yoke, [0071] 202 magnetic pole, 202a pressing bar, [0072] 203 winding, 203a winding end portion; [0073] 204 iron core, 204a tooth portion, [0074] 204b slot; [0075] 205 radial cooling passage, 206 slot wedge, [0076] 207 second iron core fastener, 208 iron core support, [0077] 209 tooth pressing plate, 210 first iron core fastener, [0078] 210t airflow passage, 210a first passage, [0079] 210b second passage, 210h recovery passage, [0080] 211 side wall passage, 212 busbar, [0081] 213 enclosing plate, 214 end cover sealing ring, [0082] 215 rotor end cover; [0083] 10 vortex flow separator, 101 vortex flow separation pipe, [0084] 101a vortex flow chamber, 101a1 end plate, [0085] 1101b hot end pipe section, 101c cold end pipe section, [0086] 101d cold end, 101e hot end, [0087] 102 jet pipe, 103 throttling member, [0088] annular spray pipe, 20a airflow dividing pipe, [0089] 20b connecting pipe, 40 cold airflow main pipe, [0090] 401 branch pipe, 50 hot airflow confluence pipe, [0091] air filter, 70 compressor, [0092] a air gap, s clearance.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0093] For making those skilled in the art better understand the technical solution of the present application, the present application will be described further in detail hereinafter in conjunction with the drawings and embodiments.
[0094] A heat exchange or drying device for an iron core according to the present embodiment includes a sprayer capable of introducing airflow. The airflow may be cold airflow or hot airflow, which is not limited to introduction of only the cold airflow or only the hot airflow, and the introduction of the cold airflow and the hot airflow can be switched in different periods according to actual needs. Introduction of the cold airflow can perform cooling and drying functions at the same time, and introduction of the hot airflow can better perform the drying function. The sprayer is provided with spray holes, and the airflow introduced into the sprayer can be sprayed to an end portion of the iron core through the spray holes, to cool and dry the end portion of the iron core.
FIRST EMBODIMENT
[0095] Referring to
[0096] As shown in
[0097] The iron core 204 is in an annular shape, therefore, in this embodiment, the sprayer is specifically an annular spray pipe 20 matching with the annular shape of the iron core 204. The annular spray pipe 20 is arranged at an end portion of the iron core 204, and multiple spray holes are provided in a circumferential direction of the annular spray pipe 20. The matching herein refers to that a diameter of the annular spray pipe 20 is substantially equal to that of the iron core 204, which means that the diameter of the annular spray pipe 20 may be equal to, or slightly greater than or slightly less than that that of the iron core 204, so that when the multiple spray holes of the annular spray pipe 20 sprays the airflow, the airflow can reach the whole annular end portion of the iron core 204. Diameters of the spray holes may be equal or different. For example, a spray hole closer to an airflow inlet of the annular spray pipe 20 may have a smaller diameter, and a spray hole farther away from the airflow inlet may have a larger diameter, so that spraying flow of all spray holes may be more uniform.
[0098] It can be understood that, for this purpose, the annular spray pipe 20 does not have to be a complete annular shape. For example, the annular spray pipe 20 may include a plurality of segments, and intervals may be provided between the plurality of segments; or, no interval is provided between the segments, and the segments are spliced or sleeved to form the annular shape. In an embodiment, the sprayer may also be an arc segment, which can rotate to achieve 360 degree spraying. Segmented arrangement is conducive to transportation and storage and convenient for replacement and maintenance, which reduces maintenance costs. It can be understood that the specific shape of the sprayer is not limited in this embodiment, and the requirements can be met as long as the whole annular end portion of the iron core 204 can be basically sprayed. Of course, in a case that the annular spray pipe 20 is annular, the introduction of the airflow is convenient to control.
[0099] As shown in
[0100] Two ends of the iron core 204 are provided with two end faces, respectively, so each of the two end faces of the iron core 204 may be provided with the annular spray pipe 20 shown in
[0101] As shown in
[0102]
[0103] As shown in
[0104] Or, a support foot is provided at the end face of the iron core 204, and the annular spray pipe 20 supported by the support foot may be arranged to face the windings 203 in the axial direction. In this case, the spray holes are arranged at the bottom of the annular spray pipe 20 to spray directly toward the windings 203 in the axial direction, and the airflow can enter into the windings 203 and the roots of the slots 204b. Of course, the spray holes in the annular spray pipe 20 may be arranged to be tilted, so as to achieve the above purpose. In addition, a nozzle may further be provided at the annular spray pipe 20, and an extending length and a spraying angle of the nozzle can be arranged according to needs, so as to control a target position of the spraying. The airflow may be sprayed in the axial direction or the radial direction, or both the axial and radial directions at the same time, and may also be sprayed with other angles.
[0105] As shown in
[0106] With continued reference to
[0107] In
[0108] The jet pipe 102 of the vortex flow separator 10, which serves as the cold source carried by the iron core 204 itself in the electromagnetic device, is an energy conversion component that converts pressure energy of compressed air into kinetic energy carried by high-speed airflow. The jet pipe 102 may include an inlet section, a body section, and an outlet section, and the outlet section is provided with a nozzle for spraying the airflow. The nozzle is a common energy conversion component of a thermal power device or a refrigeration device. Spiral airflow is formed after the airflow passes through the jet pipe 102, as shown in
[0109] Since the cross-sectional area of the cold end pipe section 101c is relatively small, as for the spiral airflow entering the vortex flow chamber 101a, resistance at the cold end 101d orifice plate is relatively large, and the airflow tangentially swirled into the vortex flow separation pipe 101 flows toward the hot end pipe section 101b in an opposite direction of the cold end 101d. Here, a cross-sectional area of the hot end pipe section 101b may be equal to or greater than that of the vortex flow chamber 101a, to ensure that the spiral airflow will flow toward the hot end pipe section 101b.
[0110] A valve having a conical surface is further provided in the hot end pipe section 101b, the valve is specifically embodied as a conical throttling member 103 as shown in
[0111] Central airflow of the spiral airflow will collide with the throttling member 103. After colliding with the conical surface of the throttling member 103, the airflow is guided by the conical surface of the throttling member 103, to flow swirlingly in an opposite direction to form reflux airflow. During the above flowing process, the airflow will be cooled down gradually, and a temperature of the cooling airflow can be greatly reduced to 50 to 10 C. The external airflow and the central airflow herein are defined with respect to a center line of the spiral airflow, the spiral airflow close to the center line is the central airflow, and the airflow away from the center line and close to a radially outermost side of the spiral airflow is the external airflow. In order to ensure that the spiral airflow flows to the hot end pipe section 101b and then flows reversely, to form the hot airflow and the cold airflow, the throttling member 103 may be arranged at a tail end of the hot end pipe section 101b.
[0112] In the above technical solution, since it is required that the spiral flow can flow reversely after passing through the valve, the conical throttling member 103 is provided. For forming the reflux spiral airflow, the valve is only required to have a certain range of a conical surface, for example, the valve is like a truncated cone (that is, a section of a cone without a cone tip), or a half cone formed by cutting a cone in an axial direction. However, it can be understood that, in order to better form a choking effect and to better guide the reflux spiral airflow, it is preferred that the valve is provided to be a complete cone as shown in
[0113] It can be seen that, the vortex flow separator 10 of the iron core 204 of the electromagnetic device which carries the cold source itself can generate a temperature separation effect that performs temperature separation to a stream of airflow, to obtain two streams of airflow, that is, cold airflow and hot airflow, and an extremely large temperature difference exists between the two streams of airflow. The vortex flow separator 10 is researched based on the phenomenon of tornadoes.
[0114] A tornado is a strong cyclone phenomenon in nature that occurs under certain atmospheric conditions. Oceanic vortices that travel vertically from a water surface to a seabed may also be generated in the ocean under certain atmospheric conditions. A typical tornado airflow structure shows that a tornado center is a funnel-like or trumpet-like pointed cone. This cone is a convolution zone of the tornado, a swirling direction of the cone is the same as that of rising hot airflow at a periphery filled with dust, but an axial flow direction of the airflow in the central cone is opposite to that of the rising airflow at the periphery, and the airflow in the central cone flows downward. Cold airflow in the central cone of a tornado is traced and measured in the natural environment, and a falling flow rate of the cold airflow can reach 17 m/s. Once a cone tip of the center cone diverges, the tornado is rapidly strengthened and the cone tip disappears and becomes a truncated cone. The hot airflow at the periphery swirls while rises, and when reaching a bottom surface of a cold cloud layer at an upper layer or the stratosphere, the airflow will immediately diverge swirlingly in a flare shape in a horizontal direction and change the swirling direction to be reversely thrown swirlingly. The air swirls rapidly around an axis of the tornado, being drawn due to extreme reduction of an air pressure at a center of the tornado, the airflow is drawn into a bottom of a vortex flow from all directions in a thin layer of air which is tens of meters thick close to the ground, and then becomes the vortex flow that swirls upward around the axis at a high speed. Therefore, the air in the tornado is always cyclonic, and a central air pressure is 10% lower than that of a surrounding air pressure, and the central air pressure is generally as low as 100 hPa, and a minimum value is 200 hPa. The tornado has a great sucking effect, which can suck sea water or lake water away from a sea surface or a lake surface, to form a water column to be connected with the cloud, commonly known as dragon sucking water.
[0115] The energy source of the tornado: one energy source is heat energy of the airflow at the periphery of the tornado, and another energy source is vacuum energy in a low pressure zone at a center of the vortex flow. High temperature air of the airflow at the periphery of the tornado interacts with the tornado, causing the thermal energy to be converted into rotational kinetic energy. The mechanism is explained by the Crocco theorem. The Crocco theorem is obtained in a fluid vortex flow field based on the first law of thermodynamics, that is, conservation of energy. The theorem quantitatively expresses a relationship among a gradient of thermodynamic enthalpy, a gradient of entropy and swirling intensity of the vortex flow in the vortex flow field. Temperature differences in the atmosphere and up and down convection are prerequisites for the formation of the tornado vortex flow, and the energy that enhances the tornado vortex flow comes from the surrounding heat energy. The gradient of the thermodynamic enthalpy formed between the rising hot airflow at the periphery of the tornado and the falling cold airflow at the center of the vortex flow becomes a key factor in the conversion of atmospheric heat energy into flowing kinetic energy of the vortex flow. After intensity of the tornado reaches a certain degree with the help of the heat energy, further intensification depends on the vacuum energy in the low pressure zone at the center of the vortex flow. A lower cone of the tornado center is in the same swirling direction as the peripheral airflow. The airflow in the lower cone swirls while falling and converges toward the center at the same time. After a centripetal accelerated speed exceeds a certain critical value, the swirling of the radial peripheral airflow is accelerated by viscous diffusion during the radial confluence process under an effect of Coriolis force.
[0116] That is, the tornado has a total temperature separation phenomenon. The vortex flow separator 10 according to this embodiment is similar to the tornado, and the jet pipe 102 is provided to make the compressed airflow form spiral airflow, which can be regarded as a spiral flow of a small-scale tornado. In this way, the total temperature separation of the tornado is simulated in the vortex flow separation pipe 101, and thereby the desired hot and cold airflow are formed.
[0117] The mechanism of this technical solution is sought hereinabove from the nature world, and the principle of the temperature separation effect of the vortex flow separator 10 will be described hereinafter.
[0118] Referring to
[0119] According to the law of energy conservation, a sum of the energy of the cold airflow and the hot airflow flowing out from the vortex flow separation pipe 101 should be equal to the energy of the compressed gas entering the jet pipe 102 of the vortex flow separator 10 (provided that the vortex flow separator 10 is well insulated). Therefore, there is necessarily a process of energy redistribution in the vortex flow separator 10 to transfer a portion of the energy from the cooling airflow to the hot airflow.
[0120] Firstly, the compressed gas is supplied to the jet pipe 102, which is hereinafter referred to as a high-pressure gas. A compressor may be provided and the compressed gas is provided by the compressor. To prevent the provided cooling airflow from affecting an internal environment of the iron core 204, an air filter may be provided at an inlet of the compressor.
[0121] The airflow of the compressed gas expands and accelerates in the jet pipe 102 of the vortex flow separator 10, and an airflow speed may approach the sound speed when the airflow is entering the vortex flow chamber 101a of the vortex flow separation pipe 101. In a case that a convergent-divergent jet pipe 102 is employed, the above airflow speed will exceed the sound speed. Since the airflow rapidly expands and passes through the jet pipe 102, which can be approximately regarded as an adiabatic process. The airflow speed is very high at the nozzle located at the outlet of the jet pipe 102, and a corresponding thermodynamic temperature of the airflow at the nozzle is much lower than a temperature of the airflow at the inlet of the jet pipe 102, that is, a primary controllable temperature drop is performed.
[0122] After the airflow enters the vortex flow chamber 101a of the vortex flow separation pipe 101 in the tangential direction, the airflow continues to move spirally along an inner wall of the vortex flow chamber 101a to form high-speed swirling airflow. When the airflow just flows out of the jet pipe 102, V=const or r=const, where V is a tangential speed of the airflow and is an angular speed. This type of swirling is also called the free vortex flow. As shown in
[0123] The formation of the hot airflow is as follows. Since the flowing of the airflow just coming out of the jet pipe 102 is the free vortex flow, the angular speed has a gradient in the radial direction, causing friction between radial layers of the airflow, such that an angular speed of the external airflow of the spiral airflow is gradually increased, and an angular speed of the central airflow of the spiral airflow is gradually reduced. However, because of the fast flow and short flowing path, the spiral airflow has not reached the full forced vortex flow, but progresses to a central portion thereof. The external airflow of the spiral airflow moves spirally in the hot end pipe section 101b, which includes both swirling movement and axial movement. During the movement, the external airflow rubs against an inner wall of the hot end pipe section 101b, thus the speed of the external airflow becomes lower and lower, the temperature of the external airflow gradually rises, and the external airflow eventually flows out through the annular clearance between the throttling member 103 and the hot end pipe section 101b. By adjusting the clearance between the throttling member 103 and the hot end pipe section 101b, a ratio of the cold airflow to the hot airflow can be adjusted.
[0124] The formation of the cold airflow is as follows. The airflow is embodied as the free vortex flow when the airflow just flows out of the jet pipe 102. Under an action of a centrifugal force, and being blocked by the cold end 101d orifice plate of the cold end pipe section 101c, the airflow will flow, near the inner wall of the hot end pipe section 101b, toward the throttling member 103. During the flowing process, due to gradual dissipation of an axial speed, when the spiral airflow moves to a certain position in the axial direction, the axial speed of the spiral airflow is already close to zero, the above position may be defined as a stagnation point. At this time, because the central airflow converges at the stagnation point, a pressure is continuously increased, and the pressure at the stagnation point is higher than a cold end 101d pressure at the outlet of the cold end pipe section 101c, thus reverse axial movement occurs in a central region of the hot end pipe section 101b, that is, reflux airflow starts from the stagnation point, and is gradually cooled down to form the cold airflow, that is, a secondary temperature drop is performed. At the stagnation point, a total temperature of the external airflow is higher than that of the central airflow. During the movement of the reverse flow to the cold end pipe section 101c, a portion of the spiral flow at an outer layer is continuously diverted to join the reverse flow, thus the reverse flow gradually expands, and a flow rate of the reverse flow reaches a maximum when the reverse flow reaches the cold end 101d orifice plate.
[0125] As shown in
[0126] In any cross section of the flow passage, a tangential speed of the airflow at any point is dominant. Near the nozzle of the jet pipe 102, both a radial speed and an axial speed of the airflow reach a maximum and then gradually decrease in respective directions.
[0127] As described above, after leaving the nozzle, the airflow enters the vortex flow separation pipe 101 in the tangential direction, and the airflow is divided into two regions. The external airflow tangentially swirls toward a hot end 101e outlet of the hot end pipe section 101b along the inner wall of the vortex flow separation pipe 101, that is, the external airflow in an outer layer region forms the free vortex flow. The central airflow flows back from the position where the throttling member 103 is arranged, due to driving of the surrounding free vortex flow, and then with the friction, an inner layer region (the central airflow) in which the airflow swirls like a rigid body is converted into or to be close to the forced vortex flow.
[0128] A boundary between external and central regions, that is, the external airflow and the reflux central airflow, depend on a magnitude of a cold airflow rate. The boundary between the cold and hot airflow can be seen in
[0129] A central airflow temperature of the central airflow is highest at the throttling member 103, the reverse flow is gradually cooled down, and the central airflow temperature is lowest when the airflow reaches the cold end 101d orifice plate. A maximum temperature difference occurs in a direction of the central axis, the highest temperature is at a position of the central axis corresponding to the throttling member 103, and the lowest temperature is at a position of the central axis corresponding to the cold end 101d orifice plate. As for the central airflow at the inner layer, that is, the cold airflow, a static temperature is lowest at the central axis and reaches the maximum at the boundary between the inner layer airflow and the outer layer airflow.
[0130] In any cross section of the flow passage of the vortex flow separation pipe 101, the total temperature is highest at a position near the inner wall surface of the vortex flow separation pipe 101 and lowest at the central axis. At the cross section of the flow passage at the nozzle, a temperature difference between a wall temperature of the vortex flow separation pipe 101 and a temperature at the central axis reaches a maximum value.
[0131] The total temperature separation effect of the vortex flow separator 10 may refer to
[0132] In
[0133] During the whole working process, it is impossible for the airflow to be isentropically expanded in the jet pipe 102. Due to a certain loss in kinetic energy exchange between airflow in the inner and outer layer regions in the vortex flow chamber 101a, and a heat transfer process toward a center in the vortex flow chamber 101a, the airflow is deviated from the adiabatic expansion process in the process from point 1 to point 2, causing the temperature T.sub.c of the cold airflow separated from the vortex flow separation pipe 101 to always be higher than the temperature T.sub.s of the cold airflow under the adiabatic expansion condition.
[0134] The cooling effect and heating effect of the vortex flow separator 10 in the above embodiment are described hereinafter.
[0135] During operation, the gas with a temperature T.sub.l is separated into cold airflow with the temperature T.sub.c and hot airflow with the temperature T.sub.h by the vortex flow separation pipe 101. Therefore, T.sub.c=T.sub.1T.sub.c is called the cooling effect of the vortex flow separation pipe 101, and T.sub.h=T.sub.hT.sub.1 is called the heating effect of the vortex pipe. T.sub.s=T.sub.1T.sub.s is defined as an isentropic expansion effect to represent a theoretical cooling effect of the vortex flow separation pipe 101. Therefore, cooling effectiveness of the vortex flow separation pipe 101 is expressed by a cooling efficiency .sub.c, that is:
[0136] where p.sub.1 represents an airflow pressure at the inlet of the vortex flow separator 10, p.sub.2 represents an airflow pressure after the airflow expands in the jet pipe 102 and enters into the vortex flow chamber 101, and k represents an adiabatic index of the gas (for example, the air).
[0137] In addition, there are balances of flow and heat during the operation of the vortex flow separator 10 which are described as follows.
[0138] If flow rates of the high-speed airflow entering the vortex flow separation pipe 101, the cold airflow at the cold end 101d, and the hot airflow at the hot end 101e are indicated by q.sub.m1, q.sub.mc and q.sub.mh, respectively, then q.sub.m1=q.sub.mc+q.sub.mh.
[0139] If specific enthalpy of the above airflow are indicated by h.sub.1, h.sub.c and h.sub.h (KJ/Kg), respectively, and the kinetic energy when the airflow flows out is neglected, then q.sub.m1h.sub.1=q.sub.mch.sub.c+q.sub.mhh.sub.h.
[0140] A cold airflow flow ratio is
[0141] A corresponding relationship between enthalpy and temperature of the gas is h=C.sub.pT.
[0142] The following formulas are obtained:
[0143] A cooling capacity of the vortex flow separation pipe 101 can also be obtained as follows: the cooling capacity Q.sub.0 (kW) of the vortex flow separation pipe 101 is Q.sub.0=q.sub.mcc.sub.p(T.sub.1T.sub.c)=.sub.cq.sub.m1c.sub.pT.sub.c; then, a cooling capacity per kilogram of the cold airflow is:
and for each kilogram of high pressure gas, its unit cooling capacity q.sub.0 can be expressed as:
[0144] A heating capacity Q.sub.h (kW) of the vortex flow separation pipe 101 is: Q.sub.0=q.sub.mhc.sub.p(T.sub.hT.sub.i)=(1.sub.c)q.sub.m1c.sub.pT.sub.h
[0145] The heating capacity per kilogram of the hot airflow is:
and for each kilogram of high pressure gas, its unit heating capacity can be expressed as:
[0146] The cooling effect T.sub.c=T.sub.1T.sub.c and the unit cooling capacity q.sub.0 of the vortex flow separator pipe 101 are related to the following factors, that is, a cold airflow component .sub.c, the working pressure p.sub.1 at the inlet of the jet pipe 102, and a water vapor content in the airflow.
[0147] As for the cold airflow component .sub.c, when a value of the cold airflow component changes, T.sub.c and q.sub.0 change correspondingly, and there are maximum values of T.sub.c and q.sub.0 in a range of .sub.c from 0 to 1. In a case that .sub.c ranges from 0.3 to 0.35, T.sub.c has the maximum value; in a case that .sub.c ranges from 0.6 to 0.7, q.sub.0 reaches the maximum value. Besides, the heating effect also changes with the change of .sub.c, T.sub.h continuously increases with the increase of .sub.c without limitation.
[0148] As for the working pressure pi at the inlet of the jet pipe 102, when p.sub.1 increases, both T.sub.c and qo increase. However, when T.sub.c and q.sub.0 increases, the maximum value of T.sub.c moves in a direction in which .sub.c decreases, and the maximum value of q.sub.0 moves in a direction in which .sub.c increases.
[0149] When the gas is moist, the water vapor in the cold airflow is condensed and heat is released, so a cooling temperature rises and the cooling efficiency decreases; a temperature rise of the hot airflow is reduced, and the heating effect is weakened.
[0150] The principle of the vortex flow separator 10 is described in detail above, the hot airflow and the cold airflow can be separated by the vortex flow separator 10. The cold airflow and the hot airflow are used as the airflow entering the sprayer in all the embodiments in the present application. Specifically, in the first embodiment, the cold airflow or the hot airflow separated by the vortex flow separator 10 is introduced into the annular spray pipe 20 mounted at the end face of the iron core 204. Certainly, the cold airflow or the hot airflow sprayed by the sprayer in the present embodiment and other following embodiments can also be provided by other equipment. For example, the cold airflow may be the internal circulation airflow as described in the background technology.
[0151] Referring to
[0152] The hot airflow from the outlet of the hot end pipe section 101b of the vortex flow separator (a right end of the vortex flow separator in
[0153] It can be understood that, two airflow inlets for the cold airflow and two airflow inlets for the hot airflow are provided. In order to ensure the uniformity of the airflow spraying, more airflow inlets may be added. The airflow inlets may also not distinguished for introducing the cold airflow or the hot airflow, instead, when the cold airflow is required to be sprayed, the cold airflow can be introduced to the airflow inlet, and when the hot airflow is required, the hot airflow can be introduced to the airflow inlet.
Second Embodiment
[0154] Referring to
[0155] It can be seen from
[0156] The annular spray pipe 20 is provided with multiple spray holes along its circumferential direction, and the hot airflow output by the vortex flow separator 10 can be conveyed to the annular spray pipe 20, such that the hot airflow can flow out from the spray holes and is sprayed to the winding end portions 203a, to perform the cooling and drying function. The drying function is not only for drying the winding end portions 203a, but more importantly, a dry environment is created at the end portions of the windings 203. As shown in
[0157] Of course, the cold airflow produced by the vortex flow separator 10 may also be introduced into the annular spray pipe 20, to cool the end portions of the windings 203, which is beneficial to heat dissipation of the windings 203 and the iron core 204. The cooling airflow in the annular spray pipe 20 may come directly from the vortex flow separator 10 described in the first embodiment, or from other airflow supply devices as described above.
[0158] With continued reference to
[0159] Furthermore, an airflow dividing pipe 20a may be arranged inside the annular spray pipe 20. After entering the airflow dividing pipe 20a, the cold airflow or the hot airflow are sprayed from two ends of the airflow dividing pipe 20a. As shown in
[0160] With continued reference to
[0161] Similar to the first embodiment, the cold airflow and the hot airflow may also be provided to the airflow supply device in the second embodiment by the vortex flow separator 10. In the second embodiment, a plurality of radial cooling passages 205 running through the iron core 204 are formed in the iron core 204. In this case, multiple vortex flow separators 10 may be arranged at an inner side of an iron core support 208. The cold airflow generated by the vortex flow separators 10 can be conveyed to the radial cooling passages 205 to further cool the iron core 204.
[0162] With continued reference to
[0163] In
[0164] Each of the branch pipes 401 may be provided with two vortex flow separators 10. One branch pipe 401 supplies the airflow to the jet pipes 102 of the two vortex flow separators 10 at the same time, and the two vortex flow separators 10 supply the cooling airflow to the adjacent two cooling passages 205. As shown in
[0165] The cold end pipe section 101c of vortex flow separation pipe 101 of the vortex flow separator 10 can be inserted into the radial cooling passage 205 of the iron core 204, for example, by means of shrink fit. The cold end pipe section 101c is cooled and then inserted into the radial cooling passage 205 to be tightly pressed by expansion; or, the cold end 101d of the cold end pipe section 101c may be welded to the radial cooling passage 205; or, a connector may be welded to the radial cooling passage 205 or connected to the radial cooling passage 205 by shrink fit, and the cold end 101d of the vortex flow separation pipe 101 is connected to and in communication with the connector, as long as the cold airflow at the cold end 101d can be conveyed into the radial cooling passage 205 (or be introduced to a confluence pipe tank and a confluence main pipe, and then be distributed into the radial cooling passage 205). The specific manner is not limited in this solution.
[0166] As shown in
[0167] In
[0168] The hot airflow separated by the vortex flow separator 10 can be gathered in a hot airflow confluence box 50. In addition to being conveyed to the annular spray pipe 20, the hot airflow may also be used to dry two sides of spaces of other air gaps (such as protective coating of the permanent magnetic pole at the rotor side and the insulating varnish on a stator surface) inside the generator 200 when the wind turbine is stopped. In a case that the drying is performed when the wind turbine is stopped, the hot airflow will not increase a thermal load of the generator.
[0169] The second embodiment is substantially the same as the first embodiment, and the arrangement and the communication manner of the vortex flow separator 10 in the second embodiment is applicable to the first embodiment. The annular spray pipe 20 of the second embodiment runs through the winding end portions 203a, in this way, a structure for fixing the annular spray pipe 20 can be omitted, which simplifies the mounting and can be better targeted at establishing a dry environment for the winding end portions 203a. Of course, the annular spray pipe 20 is arranged at the end portion of the iron core 204, which is not limited to running through the winding end portions 203a or being fixed on an end face of the iron core 204. For example, the annular spray pipe 20 may also be fastened to an inner side of the iron core 204, as long as the cold airflow or the hot airflow can be sprayed to the end portion of the iron core 204. Although the position where the annular spray pipe 20 is located is not limited, the two arrangements provided by the first embodiment and the second embodiment are convenient for the mounting of the annular spray pipe 20.
Third Embodiment
[0170] Referring to
[0171] As shown in the above embodiments, the iron core 204 is generally formed by superposing multiple stacking sheets in the axial direction. In order to ensure the reliability of the superposing of the stacking sheet, multiple first iron core fasteners 210 for axially tensioning the iron core 204 are provided. For example, the first iron core fastener 210 may be a stud bolt in
[0172] In this embodiment, the first iron core fastener 210 also serves as a sprayer, and a spray hole is arranged in the first iron core fastener 210. As shown in
[0173] Specifically, as shown in
[0174] In this embodiment, the airflow supply device is provided at an inner side of the iron core support 208, and a side wall passage 211 is further provided. The side wall passage 211 successively runs through the iron core support 208, gets into the iron core 204, and runs through a side wall of the first iron core fastener 210, and then is in communication with the airflow passage 210t. In this way, the airflow supply device located at the inner side of the iron core support 208 generates the required airflow, the airflow may enter into the airflow passage 210t through the side wall passage 211, and then is sprayed from the two ends of the airflow passage 210t. The airflow supply device herein may also be the vortex flow separator 10 described above, and the specific structure of the vortex flow separator 10 can be understood with reference to the above embodiments, which is not described herein. In this embodiment, the first iron core fastener 210 of the iron core 204 is skillfully used to form an airflow conveying passage, there is no need to arrange a special airflow conveying passage, and operations such the fastening of the passage is also not needed, which is more convenient. In addition, the airflow supply device can be arranged at the inner side of the iron core support 208 in this way. The inner side of the iron core support 208 has relatively sufficient space, which facilitates the arrangement of the airflow supply device.
[0175] With continued reference to
[0176] With continued reference to
[0177] As shown in
[0178] In this embodiment, the airflow is sprayed out of the two ends of the first iron core fastener 210, to perform heat exchange at the end portions of the iron core 204, so as to achieve the purpose of cooling and drying. After the heat exchange, the airflow flows inside the rotor, and when a certain amount of airflow is accumulated, the airflow can flow out from a clearance s shown in
Fourth Embodiment
[0179] Referring to
[0180] This embodiment is substantially the same as the third embodiment, except that in the third embodiment, the airflow enters into the airflow passage 210t and is sprayed out from the two ends thereof, and in the fourth embodiment, the airflow is sprayed from one end, and a recovery passage 210h is further provided.
[0181] As shown in
[0182] In this case, the side wall passage 211 also includes an inlet passage and an outlet passage isolated from each other. The airflow enters into the airflow passage 210t from the inlet passage and is sprayed out from an end portion of the airflow passage 210t. In
[0183] For the airflow passage 210t, the first passage 210a and the second passage 210b may be formed by dividing the airflow passage 210t, to introduce the cold airflow and the hot airflow respectively. In
[0184] With this arrangement, after the airflow is sprayed from one end of the airflow passage 210t, the heat exchange is performed near the end and the cooling and/or drying functions are realized, when the airflow is accumulated to a certain amount, the airflow will flow from an air gap a between the iron core 204 and a magnetic pole 202 to the other end of the first iron core fastener 210, to perform exchange heat at the other end and enter into the recovery passage 210h at the other end of the first iron core fastener 210, and then flows out from the side wall passage 211. The airflow flowing out can be recycled. For example, after performing heat exchange and being heated, the cold airflow may be used for drying, or may also be conveyed back to the compressor 70, or may be conveyed to other places required to be dried. Certainly, in this embodiment, in a case that there is a certain clearance s, part of the airflow may also flow out from the clearance s, which has the same function as that of the third embodiment. In a case that the sealing performance is better, the recovery effect is more significant.
[0185] In the above embodiments, the heat exchange or drying device for the iron core 204 is illustrated mainly by taking the generator 200 as an example. It can be understood that, in addition to the generator 200, the above solutions may be applicable to other electromagnetic devices having the iron core 204, such as a motor, a transformer and an electric reactor.
[0186] In a case that the generator 200 is applied to a wind turbine, the hot airflow separated by the vortex flow separator 10 or the recovered temperature-rised airflow may be conveyed to at least one of the following: a front edge of a blade, a rear edge of the blade, a hub, a pitch bearing, a wind measurement support at an upper portion of a nacelle and a yaw bearing. The yaw bearing is arranged between the generator 200 and the nacelle. The hot airflow may be conveyed to the inner front edge of the blade and the rear edge of the blade, to prevent the blade from icing and frosting. Specifically, the hot airflow may be conveyed to an inner chamber close to the front edge inside the blade or an outside of the blade, or an inner chamber close to the rear edge inside the blade or the outside of the blade. The hot airflow is also conveyed to the wind measurement support at the upper portion of the nacelle, which can perform the drying function, thereby maintaining the detection sensitivity of the wind measurement support. In a case that the wind turbine 200 is not working, the hot airflow may be conveyed to an exposed surface of the pitch bearing, an interior of the yaw bearing, a space inside the hub or other parts, to perform the drying function, and the thermal load will not be increased. When the hot airflow is conveyed to the space inside the hub, a gas slip ring may be provided. It can be seen that the generator 200 is not provided with the heat source and the cold source at the same time, a single device has a dual function of the cold source and the heat source at the same time, which is both the cold source and the heat source.
[0187] In the above embodiments, the sprayer is mainly provided to spray the cold airflow or the hot airflow at the end portion of the iron core 204, that is, the cold source and the drying source are generated in the heat source (the iron core 204 and the windings 203) to cool and dry the insulation of the windings 203 and the iron core 204, so as to create a cool and dry environment at the end portion of the iron core 204, which is conducive to the heat dissipation of the iron core and the maintenance of the insulation performance of end portion of the windings 203, including the insulation of the windings 203 itself and the insulation between the windings 203 and the iron core 204, and is also conducive to the protection of the magnetic poles 202 and the protective coating thereof. The essence of the cooling and drying method is that the internal airflow will not be affected by natural environment and will not carry multiphase airflow in natural environment, which improves the internal environment, and the internal moist airflow can be squeezed or carried out to be recycled.
[0188] It can be understood that the solution of the sprayer may be carried out individually or combined with the cooling solutions described in the background technology, or as described above, multichannel cooling may be carried out by combining the radial cooling passage 205 and the cooling passage of the second fastener 207. The solutions of the annular spray pipe 20 (the first embodiment or the second embodiment) of the sprayer and the first fastener 210 (the third embodiment or the fourth embodiment) may also be performed collaboratively, to establish a multi-dimensional heat dissipation channel, so as to better perform the cooling and drying function.
[0189] It should be noted that, in the third and fourth embodiments, the airflow is conveyed through the first iron core fastener 210. When the cold airflow is conveyed, in addition to creating a cooling environment at the end portion of the iron core 204, the more important is that it is equivalent to arranging a cooling passage inside the iron core 204, and thus the iron core 204 can be better cooled.
[0190] The above embodiments are only preferred embodiments of the present application. It should be noted that, for those skilled in the art, a few of modifications and improvements may be made to the present application without departing from the principle of the present application, and these modifications and improvements are also deemed to fall into the scope of the present application defined by the claims.