A method for air gap bypass ventilation cooling of long iron core low speed wind turbine motor

Abstract

The present invention discloses a long iron core low-speed wind power motor air gap flow ventilation cooling method, which belongs to the technical field of wind power generators, and includes the following steps: S1, a stator frame with a ventilation cavity is arranged on the inner diameter side of the stator iron core, and an air gap is arranged between the stator and the rotor; S2, cooling air is passed into the cold air cavity in the cold air zone of the stator frame through a cooling fan; S3, cooling air enters the air gap through the cold air cavity and the stator iron core ventilation duct in turn, and then enters the hot air cavity in the hot air zone of the stator frame through the stator iron core ventilation duct, and cools the stator iron core and the stator coil embedded in the stator iron core slot. The present invention can not only greatly improve the uniformity of the circumferential cooling air volume through the air gap flow ventilation cooling method, but also the distribution of the wind speed through the stator iron core ventilation duct in the axial direction is more uniform than the traditional structure, which is conducive to greatly improving the cooling effect of the motor.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine generators, and in particular to an air gap flow-through ventilation cooling method for a long-core low-speed wind turbine motor. Background Art

[0002] The speed of low-speed permanent magnet wind turbine motor is low, only about 10r / min, and the pressure generated by the rotating parts is only a few Pa, which cannot drive the air to flow inside the motor to remove the loss of motor operation. Generally, a special fan is used as the main pressure source for air flow.

[0003] For larger capacity permanent magnet low-speed wind turbine motors, the core is longer and radial ventilation is adopted. After the cooling air passes through the stator, it enters the air gap and diffuses to both ends of the core, and finally passes through the stator winding end and the ventilation duct. The core is longer, and the ventilation path for the stator to be directly cooled is long. In addition, due to structural limitations, it is generally impossible to evenly arrange the fan around the base. As a result, due to the uneven circumferential temperature distribution of the stator coil and the core, the circumferential temperature difference can reach 30K-40K, making it difficult to further increase the electromagnetic load and affecting the economy of the motor.

[0004] A Chinese patent document with publication number CN110429747B and publication date November 20, 2020 discloses a method for reducing the circumferential temperature difference between a motor coil and an iron core, comprising the following steps:

[0005] a. Install a device for reducing the circumferential temperature difference between the large-diameter motor coil and the core on the wind turbine;

[0006] b. Install an oblique wind shield at the outlet of the air inlet pipe, the angle between the oblique wind shield and the first vertical plate is 30-60°, install an air volume adjustment plate on the air inlet hole, the air volume adjustment plate is hinged to the first circumferential ring plate, and the air circumferential resistance is adjusted by the air volume adjustment plate;

[0007] c. In a circumferentially symmetrical unit, the wind flow area at the fan end close to the fan axis is minimized, and the wind flow area at the fan end far from the fan axis is maximized;

[0008] The device for reducing the circumferential temperature difference between the coil and the core of a large-diameter motor comprises a rotor frame, a rotor core mounted on the rotor frame, and a plurality of rotor magnets arranged along the axial direction of the rotor core, and also comprises a plurality of stator core segments, a first core pressure plate, a second core pressure plate, and a tensioning screw, wherein the stator core segments are stacked by silicon steel sheets, the silicon steel sheets are provided with a slot body for placing the stator coil, a stator slot steel is connected between any two adjacent stator core segments, the two stator core segments and the stator slot steel form a stator ventilation groove for the circulation of cooling medium, the tensioning screw passes through the plurality of stator core segments, one end of the tensioning screw is fixedly connected to the first core pressure plate, and the other end of the tensioning screw is fixedly connected to the second core pressure plate, an air gap is arranged between the rotor magnet and the stator core segment, a first circumferential ring plate is fixedly connected to the plurality of stator core segments, and the first circumferential ring plate One end of the first iron core pressure plate is fixedly connected to the first circumferential ring plate, and the other end of the first circumferential ring plate is fixedly connected to the second iron core pressure plate, and at least three axial vertical plates are fixedly connected to the inner wall of the first circumferential ring plate, and an air inlet cavity and an air outlet cavity are formed between the first circumferential ring plate, the stator core segment and two adjacent axial vertical plates, and the air inlet cavity and the air outlet cavity are arranged at intervals, and the first circumferential ring plate is provided with a plurality of air inlet holes and a plurality of air outlet holes, and the air inlet holes are connected to the corresponding air inlet cavity, and the air outlet holes are connected to the corresponding air outlet cavity. The first vertical plate and the second vertical plate are fixedly connected to the outer wall of the first circumferential ring plate, and the second circumferential ring plate is fixedly connected between the first vertical plate and the second vertical plate, the first vertical plate is connected to an oblique wind shield plate through a plurality of connecting plates, the second circumferential ring plate is connected to an air outlet duct communicating with the air outlet cavity, and the first vertical plate is connected to an air inlet duct communicating with the air inlet cavity.

[0009] The method disclosed in the patent document for reducing the circumferential temperature difference between the motor coil and the core is simple and flexible to operate. However, the structure is complex to install and is not easy to implement, and the air volume distribution uniformity of the stator is poor, which affects the cooling effect. Summary of the invention

[0010] In order to overcome the defects of the above-mentioned prior art, the present invention provides an air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine motor. The present invention uses an air gap flow-through ventilation cooling method, which can not only greatly improve the uniformity of the circumferential cooling air volume, but also make the axial distribution of the wind speed through the stator core ventilation duct more uniform than the traditional structure, which is beneficial to greatly improve the cooling effect of the motor.

[0011] The present invention is achieved through the following technical solutions:

[0012] A method for air gap flow-through ventilation cooling of a long-core low-speed wind turbine motor comprises the following steps:

[0013] S1. A stator frame with a ventilation cavity is arranged on the inner diameter side of the stator core, and an air gap is arranged between the stator and the rotor;

[0014] S2, passing cooling air into the cold air cavity of the cold air zone of the stator frame through a cooling fan;

[0015] S3. The cooling air enters the air gap through the cold air cavity and the stator core ventilation duct in sequence, and then enters the hot air cavity in the hot air zone of the stator frame through the stator core ventilation duct to cool the stator core and the stator coil embedded in the stator core slot.

[0016] In S1, the stator includes a core pressure plate, a tightening screw, a stator coil, an iron core and a stator frame. The iron core is multi-section, and stator core slots are arranged on the iron core. A ventilation slot steel is arranged between any two adjacent iron cores. The tightening screw runs through the multi-section iron core, and the tightening screw is fixedly connected to the core pressure plate.

[0017] The stator frame includes a first ring plate, a cone cylinder, a second ring plate, a rib plate and a cylinder. There are multiple rib plates. The first ring plate, the cone cylinder, the second ring plate, the cylinder and the inner diameter of the core form an annular space. The rib plates divide the annular space into a number of evenly distributed cold air cavities and hot air cavities.

[0018] The cold air cavity and the hot air cavity are distributed at intervals along the circumference of the iron core.

[0019] In S1, the rotor includes a rotor frame and a magnetic steel, an inner diameter surface of the magnetic steel is provided with a heat insulating layer, and a heat conducting layer is provided between the outer diameter side of the magnetic steel and the rotor frame.

[0020] In S3, the stator core ventilation duct is formed by the ventilation channel steel, the stator coil and the core.

[0021] In S3, the stator coil is embedded and fixed in the stator core slot through the slot bottom pad, the interlayer pad, the wedge under pad and the slot wedge.

[0022] The outer diameter of the stator core is 10-15 mm larger than the outer diameter of the slot wedge distribution circle.

[0023] The heat insulation layer is made of stainless steel or plastic.

[0024] The heat-conducting layer is heat-conducting silica gel.

[0025] The beneficial effects of the present invention are mainly manifested in the following aspects:

[0026] 1. Compared with the prior art, the present invention can not only greatly improve the uniformity of the circumferential cooling air volume through the air gap flow ventilation cooling method, but also the axial distribution of the wind speed through the stator core ventilation duct is more uniform than the traditional structure, which is beneficial to greatly improve the cooling effect of the motor.

[0027] 2. The present invention adopts a specific air gap flow method. Compared with the traditional method of sending cooling air through the air gaps at both ends and cooling through the stator ventilation grooves, the ventilation wind resistance is significantly reduced, which is beneficial to the selection of cooling fans; the structure is simple to install and easy to implement.

[0028] 3. In the present invention, the outer diameter of the stator core is 10-15 mm larger than the outer diameter of the slot wedge distribution circle, so that the cooling air can flow circumferentially at each stator core ventilation duct, which greatly reduces the resistance to the circumferential flow of the cooling air and reduces the possibility of heat exchange between the air that has been heated up by heat exchange with the stator core and the coil and the magnetic steel, thereby reducing its heating effect on the magnetic steel.

[0029] 4. The present invention provides a heat insulation layer on the inner diameter surface of the magnet, wherein the heat insulation layer is made of stainless steel or plastic, thereby reducing the heat exchange between the magnet and the cooling air in the air gap, thereby preventing the magnet from being heated by air at a higher temperature, which may cause the magnet performance to deteriorate or even demagnetize.

[0030] 5. In the present invention, a heat-conducting layer is provided between the outer diameter side of the magnetic steel and the rotor base. The heat-conducting layer is a heat-conducting silicone rubber, which further strengthens the heat exchange with the rotor base. The eddy current loss caused by the stator harmonics on the magnetic steel is transferred to the rotor base through the magnetic steel and the high thermal conductivity material, and then is taken away by the heat exchange between the outer surface of the rotor and the atmosphere, thereby ensuring the performance of the magnetic steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0032] Figure 1 A longitudinal sectional view of the wind turbine of the present invention;

[0033] Figure 2 for Figure 1 AA view;

[0034] Figure 3 for Figure 2 The enlarged view of point A in the middle;

[0035] Figure 4 for Figure 2 The enlarged view of point B in the middle;

[0036] Markings in the figure: 1. stator, 2. core, 3. stator frame, 4. air gap, 5. cold air zone, 6. cold air cavity, 7. stator core ventilation duct, 8. hot air zone, 9. hot air cavity, 10. stator core slot, 11. stator coil, 12. core pressure plate, 13. tensioning screw, 14. ventilation channel steel, 15. first ring plate, 16. cone, 17. second ring plate, 18. rib plate, 19. cylinder, 20. rotor frame, 21. magnetic steel, 22. thermal insulation layer, 23. thermal conductive layer, 24. slot bottom pad, 25. interlayer pad, 26. wedge under pad, 27. slot wedge. DETAILED DESCRIPTION

[0037] Example 1

[0038] See also Figure 1 and Figure 2 , a long iron core low speed wind turbine motor air gap flow ventilation cooling method, comprising the following steps:

[0039] S1, a stator frame 3 with a ventilation cavity is arranged on the inner diameter side of the core 2 of the stator 1, and an air gap 4 is arranged between the stator 1 and the rotor;

[0040] S2, passing cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3 through a cooling fan;

[0041] S3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air area 8 of the stator frame 3 through the stator core ventilation duct 7 to cool the stator core 2 of the stator 1 and the stator coil 11 embedded in the stator core slot 10.

[0042] This embodiment is the most basic implementation method. Compared with the existing technology, the air gap flow ventilation cooling method can not only greatly improve the uniformity of the circumferential cooling air volume, but also the axial distribution of the wind speed through the stator core ventilation duct 7 is more uniform than the traditional structure, which is beneficial to greatly improve the cooling effect of the motor.

[0043] Example 2

[0044] See also Figure 1 and Figure 2 , a long iron core low speed wind turbine motor air gap flow ventilation cooling method, comprising the following steps:

[0045] S1, a stator frame 3 with a ventilation cavity is arranged on the inner diameter side of the core 2 of the stator 1, and an air gap 4 is arranged between the stator 1 and the rotor;

[0046] S2, passing cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3 through a cooling fan;

[0047] S3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air area 8 of the stator frame 3 through the stator core ventilation duct 7 to cool the stator core 2 of the stator 1 and the stator coil 11 embedded in the stator core slot 10.

[0048] Preferably, in S1, the stator 1 includes a core pressure plate 12, a tensioning screw 13, a stator coil 11, an iron core 2 and a stator frame 3. The iron core 2 is multi-section, and a stator core slot 10 is provided on the iron core 2. A ventilation slot steel 14 is provided between any two adjacent iron cores 2. The tensioning screw 13 passes through the multi-section iron core 2, and the tensioning screw 13 is fixedly connected to the core pressure plate 12.

[0049] The stator frame 3 includes a first ring plate 15, a cone cylinder 16, a second ring plate 17, a rib plate 18 and a cylinder 19. There are multiple rib plates 18. The first ring plate 15, the cone cylinder 16, the second ring plate 17, the cylinder 19 and the inner diameter of the core 2 form an annular space. The rib plates 18 divide the annular space into a plurality of evenly distributed cold air cavities 6 and hot air cavities 9.

[0050] This embodiment is a preferred implementation method, which adopts a specific air gap flow method. Compared with the traditional method of sending cooling air through the air gaps at both ends and cooling through the stator ventilation grooves, the ventilation wind resistance is significantly reduced, which is beneficial to the selection of cooling fans; the structure is simple to install and easy to implement.

[0051] Example 3

[0052] See also Figure 1-Figure 4 , a long iron core low speed wind turbine motor air gap flow ventilation cooling method, comprising the following steps:

[0053] S1, a stator frame 3 with a ventilation cavity is arranged on the inner diameter side of the core 2 of the stator 1, and an air gap 4 is arranged between the stator 1 and the rotor;

[0054] S2, passing cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3 through a cooling fan;

[0055] S3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air area 8 of the stator frame 3 through the stator core ventilation duct 7 to cool the stator core 2 of the stator 1 and the stator coil 11 embedded in the stator core slot 10.

[0056] In S1, the stator 1 includes a core pressure plate 12, a tensioning screw 13, a stator coil 11, an iron core 2 and a stator frame 3. The iron core 2 is multi-section, and a stator core slot 10 is provided on the iron core 2. A ventilation slot steel 14 is provided between any two adjacent iron cores 2. The tensioning screw 13 passes through the multi-section iron core 2, and the tensioning screw 13 is fixedly connected to the core pressure plate 12.

[0057] The stator frame 3 includes a first ring plate 15, a cone cylinder 16, a second ring plate 17, a rib plate 18 and a cylinder 19. There are multiple rib plates 18. The first ring plate 15, the cone cylinder 16, the second ring plate 17, the cylinder 19 and the inner diameter of the core 2 form an annular space. The rib plates 18 divide the annular space into a plurality of evenly distributed cold air cavities 6 and hot air cavities 9.

[0058] The cold air cavity 6 and the hot air cavity 9 are distributed at intervals along the circumference of the core 2 .

[0059] Further preferably, in S1, the rotor includes a rotor base 20 and a magnetic steel 21 , a heat insulating layer 22 is provided on the inner diameter surface of the magnetic steel 21 , and a heat conducting layer 23 is provided between the outer diameter side of the magnetic steel 21 and the rotor base 20 .

[0060] In S3 , the stator core ventilation passage 7 is formed by the ventilation channel steel 14 , the stator coil 11 and the core 2 .

[0061] In S3 , the stator coil 11 is embedded and fixed in the stator core slot 10 through the slot bottom pad 24 , the interlayer pad 25 , the wedge under pad 26 and the slot wedge 27 .

[0062] The outer diameter of the core 2 of the stator 1 is 10 mm larger than the outer diameter of the distribution circle of the slot wedges 27 .

[0063] This embodiment is another preferred implementation method. The outer diameter of the core 2 of the stator 1 is larger than the outer diameter of the distribution circle of the slot wedge 27, so that the cooling air can flow circumferentially at each stator core ventilation duct 7, which greatly reduces the resistance to the circumferential flow of the cooling air. At the same time, it reduces the possibility of heat exchange between the air that has been heated up by heat exchange with the stator core and the coil and the magnetic steel 21, thereby reducing its heating effect on the magnetic steel 21.

[0064] Example 4

[0065] See also Figure 1-Figure 4 , a long iron core low speed wind turbine motor air gap flow ventilation cooling method, comprising the following steps:

[0066] S1, a stator frame 3 with a ventilation cavity is arranged on the inner diameter side of the core 2 of the stator 1, and an air gap 4 is arranged between the stator 1 and the rotor;

[0067] S2, passing cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3 through a cooling fan;

[0068] S3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air area 8 of the stator frame 3 through the stator core ventilation duct 7 to cool the stator core 2 of the stator 1 and the stator coil 11 embedded in the stator core slot 10.

[0069] In S1, the stator 1 includes a core pressure plate 12, a tensioning screw 13, a stator coil 11, an iron core 2 and a stator frame 3. The iron core 2 is multi-section, and a stator core slot 10 is provided on the iron core 2. A ventilation slot steel 14 is provided between any two adjacent iron cores 2. The tensioning screw 13 passes through the multi-section iron core 2, and the tensioning screw 13 is fixedly connected to the core pressure plate 12.

[0070] The stator frame 3 includes a first ring plate 15, a cone cylinder 16, a second ring plate 17, a rib plate 18 and a cylinder 19. There are multiple rib plates 18. The first ring plate 15, the cone cylinder 16, the second ring plate 17, the cylinder 19 and the inner diameter of the core 2 form an annular space. The rib plates 18 divide the annular space into a plurality of evenly distributed cold air cavities 6 and hot air cavities 9.

[0071] The cold air cavity 6 and the hot air cavity 9 are distributed at intervals along the circumference of the core 2 .

[0072] In S1 , the rotor includes a rotor frame 20 and a magnetic steel 21 . A heat insulating layer 22 is provided on the inner diameter surface of the magnetic steel 21 , and a heat conducting layer 23 is provided between the outer diameter side of the magnetic steel 21 and the rotor frame 20 .

[0073] In S3 , the stator core ventilation passage 7 is formed by the ventilation channel steel 14 , the stator coil 11 and the core 2 .

[0074] In S3 , the stator coil 11 is embedded and fixed in the stator core slot 10 through the slot bottom pad 24 , the interlayer pad 25 , the wedge under pad 26 and the slot wedge 27 .

[0075] The outer diameter of the core 2 of the stator 1 is 12 mm larger than the outer diameter of the distribution circle of the slot wedges 27 .

[0076] The heat insulation layer 22 is made of stainless steel.

[0077] This embodiment is another preferred implementation manner. By setting a heat insulation layer 22 on the inner diameter surface of the magnetic steel 21, the heat insulation layer 22 is made of stainless steel. This can reduce the heat exchange between the magnetic steel 21 and the cooling air in the air gap 4, thereby preventing the magnetic steel 21 from being heated by air at a higher temperature, which may cause the performance of the magnetic steel 21 to deteriorate or even demagnetize.

[0078] Example 5

[0079] See also Figure 1-Figure 4 , a long iron core low speed wind turbine motor air gap flow ventilation cooling method, comprising the following steps:

[0080] S1, a stator frame 3 with a ventilation cavity is arranged on the inner diameter side of the core 2 of the stator 1, and an air gap 4 is arranged between the stator 1 and the rotor;

[0081] S2, passing cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3 through a cooling fan;

[0082] S3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air area 8 of the stator frame 3 through the stator core ventilation duct 7 to cool the stator core 2 of the stator 1 and the stator coil 11 embedded in the stator core slot 10.

[0083] In S1, the stator 1 includes a core pressure plate 12, a tensioning screw 13, a stator coil 11, an iron core 2 and a stator frame 3. The iron core 2 is multi-section, and a stator core slot 10 is provided on the iron core 2. A ventilation slot steel 14 is provided between any two adjacent iron cores 2. The tensioning screw 13 passes through the multi-section iron core 2, and the tensioning screw 13 is fixedly connected to the core pressure plate 12.

[0084] The stator frame 3 includes a first ring plate 15, a cone cylinder 16, a second ring plate 17, a rib plate 18 and a cylinder 19. There are multiple rib plates 18. The first ring plate 15, the cone cylinder 16, the second ring plate 17, the cylinder 19 and the inner diameter of the core 2 form an annular space. The rib plates 18 divide the annular space into a plurality of evenly distributed cold air cavities 6 and hot air cavities 9.

[0085] The cold air cavity 6 and the hot air cavity 9 are distributed at intervals along the circumference of the core 2 .

[0086] In S1 , the rotor includes a rotor frame 20 and a magnetic steel 21 . A heat insulating layer 22 is provided on the inner diameter surface of the magnetic steel 21 , and a heat conducting layer 23 is provided between the outer diameter side of the magnetic steel 21 and the rotor frame 20 .

[0087] In S3 , the stator core ventilation passage 7 is formed by the ventilation channel steel 14 , the stator coil 11 and the core 2 .

[0088] More preferably, in S3 , the stator coil 11 is embedded and fixed in the stator core slot 10 through the slot bottom pad 24 , the interlayer pad 25 , the wedge under pad 26 and the slot wedge 27 .

[0089] The outer diameter of the core 2 of the stator 1 is 15 mm larger than the outer diameter of the distribution circle of the slot wedges 27 .

[0090] The heat insulation layer 22 is made of plastic.

[0091] The heat-conducting layer 23 is made of heat-conducting silica gel.

[0092] This embodiment is the best implementation method. A heat-conducting layer 23 is provided between the outer diameter side of the magnetic steel 21 and the rotor frame 20. The heat-conducting layer 23 is a heat-conducting silicone rubber, which further strengthens the heat exchange with the rotor frame 20. The eddy current loss caused by the stator harmonics on the magnetic steel 21 is transmitted to the rotor frame 20 through the magnetic steel 21 and the high thermal conductivity material, and then is taken away by the heat exchange between the outer surface of the rotor and the atmosphere, thereby ensuring the performance of the magnetic steel 21.

[0093] The basic principles of the present invention are as follows:

[0094] By setting an air gap 4 between the stator 1 and the rotor, the cooling fan passes the cooling air into the cold air cavity 6 of the cold air zone 5 of the stator frame 3. The cooling air enters the air gap 4 through the cold air cavity 6 and the stator core ventilation duct 7 in turn, and then enters the hot air cavity 9 of the hot air zone 8 of the stator frame 3 through the stator core ventilation duct 7. Compared with the traditional method of sending the cooling air through the air gaps at both ends and cooling through the stator ventilation groove, this specific air gap flow bypass method significantly reduces the ventilation wind resistance, which is beneficial to the selection of the cooling fan; and due to the effects of the cold air cavity 6 and the hot air cavity 9, the axial distribution of the wind speed through the stator core ventilation duct 7 can be made more uniform than the traditional structure, which is beneficial to improving the cooling effect.

Claims

1. A long-core low-speed wind turbine air gap flow-through ventilation cooling method, characterized in that: The following steps are involved: S1, a stator frame (3) with a ventilation cavity is arranged on the inner diameter side of the iron core (2) of the stator (1), and an air gap (4) is arranged between the stator (1) and the rotor; S2, passing cooling air into the cold air cavity (6) of the cold air zone (5) of the stator frame (3) through a cooling fan; S3, cooling air enters the air gap (4) through the cold air cavity (6) and the stator core ventilation duct (7) in sequence, and then enters the hot air cavity (9) of the hot air zone (8) of the stator frame (3) through the stator core ventilation duct (7), thereby cooling the stator core (2) of the stator (1) and the stator coil (11) embedded in the stator core slot (10); In S1, the rotor comprises a rotor base (20) and a magnetic steel (21), the inner diameter surface of the magnetic steel (21) is provided with a heat insulation layer (22), and a heat conduction layer (23) is provided between the outer diameter side of the magnetic steel (21) and the rotor base (20); In the above-mentioned S3, the stator coil (11) is embedded and fixed in the stator core slot (10) through the slot bottom pad (24), the interlayer pad (25), the wedge under pad (26) and the slot wedge (27); The outer diameter of the iron core (2) of the stator (1) is 10-15 mm larger than the outer diameter of the distribution circle of the slot wedge (27); The heat-conducting layer (23) is heat-conducting silica gel.

2. The air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine according to claim 1 is characterized in that: In the S1, the stator (1) comprises a core pressure plate (12), a tensioning screw (13), a stator coil (11), a core (2) and a stator frame (3); the core (2) is multi-sectioned, the core (2) is provided with stator core slots (10), a ventilation slot steel (14) is provided between any two adjacent cores (2), the tensioning screw (13) passes through the multi-section core (2), and the tensioning screw (13) is fixedly connected to the core pressure plate (12).

3. The air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine according to claim 1 is characterized in that: The stator frame (3) comprises a first ring plate (15), a cone cylinder (16), a second ring plate (17), a rib plate (18) and a cylinder (19), wherein the rib plates (18) are multiple, and the first ring plate (15), the cone cylinder (16), the second ring plate (17), the cylinder (19) and the inner diameter of the core (2) form an annular space, and the rib plates (18) divide the annular space into a plurality of evenly distributed cold air cavities (6) and hot air cavities (9).

4. The air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine according to claim 1 is characterized in that: The cold air cavity (6) and the hot air cavity (9) are distributed at intervals along the circumference of the iron core (2).

5. The air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine according to claim 2 is characterized in that: In S3, the stator core ventilation duct (7) is formed by the ventilation channel steel (14), the stator coil (11) and the core (2).

6. The air gap flow-through ventilation cooling method for a long iron core low-speed wind turbine according to claim 1, characterized in that: The heat insulation layer (22) is made of stainless steel or plastic.

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