CN202586575U - Dome, cooling ventilation system and double-fed wind generator - Google Patents

Abstract

The utility model provides a guide cover, a cooling ventilation system and a double-fed wind power generator. The cooling and ventilation system is used for a wind power generator, the wind power generator includes a ring plate and a support plate for supporting the ring plate, and the cooling and ventilation system includes a shroud arranged at least at one end of the rotor. The shroud includes an annular portion and an arc portion extending along the inner peripheral surface of the annular portion. The radial cross-section of the arc is circular, and the inner diameter of the circular decreases gradually from the first end of the arc to the second end of the arc; the shroud is sleeved in the ring plate, and The ring plate is fixedly connected. The utility model installs a shroud at the end of the rotor, eliminating the need for an axial flow fan, and uses the wind pressure generated by the rotation of the radial ventilation holes of the rotor to drive the fluid to reach the inside of the stator winding for heat exchange, and uses the flow field at the rear end of the shroud It is divided into two paths, which avoids the eddy current loss caused by the collision with the fluid generated from the end of the rotor, makes a series of irregular stray flows tend to be orderly, and improves the air volume of the system.

Description

Shroud, cooling ventilation system and doubly-fed wind turbine

technical field

The utility model relates to the field of wind power generation, in particular to a wind deflector, a cooling ventilation system and a double-fed wind power generator.

Background technique

As a clean and renewable energy source, wind power has attracted worldwide attention. At present, the most widely used wind power generator is the doubly-fed wind power generator. When the double-fed wind turbine is working, the stator winding, rotor winding and iron core will generate a lot of heat, which needs to be cooled by the cooling system.

At present, the cooling method of double-fed wind turbines is mainly air cooling. The structure of the air cooling system is shown in Figure 1. The end ring plate 3' is installed on the annular support plate 8', and the windshield 2' is installed on the end ring. On the board 3', an axial flow fan 1' is installed under the windshield 2'. The rotor 5' is mounted on the rotor bracket 4', the rotor 5' is provided with axial ventilation holes 6' and radial ventilation holes 7', and the stator is provided with radial ventilation holes 9'. When cooling, the cooling air flows out from the air outlet of the cooler and then passes through the axial flow fan 1', the rotor bracket 4', the rotor axial ventilation hole 6', the rotor radial ventilation hole 7', the air gap between the rotor and the stator, The stator radial ventilation hole 9' enters the cooler for heat exchange and completes a cycle. The circulating air takes heat away from the rotor and stator, cooling them. However, this cooling method has the following disadvantages: the cooling air needs the axial flow fan 1' to pressurize it, and a mounting seat for installing the axial flow fan 1' needs to be provided, which makes the system structure complicated. In addition, the gas flowing out from the axial flow fan 1' collides with the fluid generated at the end of the rotor to generate eddy currents, resulting in excessive loss, which sharply reduces the flow of fluid passing through the stator and rotor, and the flow performance of the air inlet is poor, and the winding end Internal cooling could be improved.

Utility model content

The utility model provides a guide cover, which is used for the cooling and ventilation system of the wind power generator, which solves the problem of complex structure of the existing cooling system, large loss caused by eddy current generated by fluid collision during the cooling process, and winding end The internal cooling problem is not in place. Another aspect of the present invention also provides a cooling and ventilation system with the above-mentioned wind deflector and a doubly-fed wind power generator with the cooling and ventilation system.

On the one hand, the utility model provides a shroud, the shroud includes an annular portion and an arc portion extending along the inner peripheral surface of the annular portion; wherein the radial section of the arc portion is circular, and the circular The inner diameter of the arc portion gradually decreases from the first end of the arc portion to the second end of the arc portion.

Further, the ring portion and the arc portion are integrally formed.

The overall shape of the shroud in the utility model is streamlined, and it is a smooth transition from the ring part to the arc part. When the fluid flows through, it can reduce the resistance and reduce the loss, so that the fluid can maintain better flowability and higher pressure. head.

On the other hand, the utility model also provides a cooling ventilation system for a wind power generator. The wind power generator includes a ring plate and a support plate for supporting the ring plate. The cooling ventilation system includes a flow guide at least at one end of the rotor A shroud; wherein the shroud includes an annular portion and an arc portion extending along the inner peripheral surface of the annular portion; wherein the radial section of the arc portion is circular, and the inner diameter of the annular portion is from the first end of the arc portion It gradually decreases to the second end of the arc portion; the shroud is sleeved in the ring plate and fixedly connected with the ring plate.

Further, the ring portion and the arc portion are integrally formed.

Further, ventilation holes are provided on the support plate.

Further, the ventilation holes are evenly distributed along the circumference of the support plate.

Further, the radius of the radial section of the second end of the arc portion is smaller than or equal to the minimum radius of the radial section of the rotor winding.

Further, the distance from the annular portion of the shroud to the end of the stator close to the annular portion is 50-100 mm.

The utility model installs a shroud at the end of the rotor, which saves the axial flow fan, uses the wind pressure generated by the rotation of the radial ventilation holes of the rotor to drive the fluid to reach the inside of the stator winding for heat exchange, and avoids heat exchange with the rotor end. The eddy current loss caused by the collision of the fluid makes a series of irregular stray flows tend to be orderly and improves the air volume of the system.

In another aspect, the utility model also provides a doubly-fed wind power generator, which is provided with the cooling and ventilation system described in any one of the above.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the axial sectional view of existing doubly-fed wind turbine cooling system;

Fig. 2 is an axial sectional view of an embodiment of the cooling ventilation system of the present invention;

Fig. 3 is a perspective view of an embodiment of a shroud of the present invention;

Fig. 4 is a perspective view of the other side of the embodiment of the shroud of the utility model;

Fig. 5 is an axial cross-sectional view of an embodiment of the shroud of the present invention;

Fig. 6 is a top view of an embodiment of the shroud of the utility model;

7 is a perspective view of the rotor shaft in the embodiment of the cooling ventilation system of the present invention;

In the figure: 1. Shroud, 2. Support plate, 3. Cooler, 4. Rotor bracket, 5. Rotor, 6. Ring plate, 7. Stator, 8. Cavity at the end of stator and rotor winding, 9. Stator End cavity, 10, bolts, 11, air gap between stator and rotor, 12, radial baffle, 14, air inlet of motor frame, 110, ring part, 120, arc part, 130, connection hole, 51, rotor axial ventilation hole, 52, rotor radial ventilation hole, 71, stator radial ventilation hole, 21, support plate ventilation hole.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, not all of them. In the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other, and, based on the embodiments in the present invention, those of ordinary skill in the art can obtain all other Embodiments all belong to the protection scope of the present invention.

Embodiment of the shroud:

Referring to Fig. 3-Fig. 6, the preferred embodiment of the shroud of the utility model is shown in the figure. As shown in the figure, the shroud includes an annular portion 110 and an arc portion 120 extending along the inner peripheral surface of the annular portion 110. The radial section of the arc portion 120 is circular, and the outer diameter of the annular The first end of the portion 120 gradually decreases to the second end of the arc portion 120 . Wherein, the first end of the arc portion 120 is an end close to the ring portion 110 , and the second end is an end away from the ring portion 110 .

It can be seen from the figure that the annular portion 110 is a planar annular structure, and a connecting hole 130 is provided near the outer circumference of the structure. The arc portion 120 is arranged on the inner peripheral surface of the ring portion 110. The radial section of the arc portion 120 is a circular ring, and the axial section is a hyperbola symmetrical to the axis. The arc inner surface of the arc portion 120 can be more Good to reduce resistance, so that the fluid has a better flow state. The radius of the radial section of the arc portion 120 gradually decreases from the first end to the second end, so that the inner surface of the arc portion 120 is a smooth transition. In addition, from the inner peripheral surface of the annular portion 110 to the arc portion 120 is also Smooth transition. It should be noted that: in this embodiment, the inner circumferential surface is a circumferential surface close to the axis, and the outer circumferential surface is a circumferential surface far away from the axis.

During specific implementation, the ring portion 110 and the arc portion 120 are preferably processed into an integrated structure.

The overall shape of the shroud in the utility model is streamlined, and it is a smooth transition from the annular part 110 to the arc part 120. When the fluid flows through, it can reduce the resistance and reduce the loss, so that the fluid can maintain better flowability and higher the indenter.

Examples of cooling ventilation systems:

Referring to Fig. 2 and Fig. 7, the preferred embodiment of the cooling ventilation system of the present invention is shown in the figure. The cooling ventilation system is used for the cooling of the generator. The following uses the doubly-fed wind power generator as an example and describes it in detail with reference to the accompanying drawings.

Referring to Fig. 2, it should be understood in conjunction with the prior art that the doubly-fed wind generator includes a rotor 5, a stator 7, a support plate 2 installed at the end of the stator 7, and a ring plate 6 installed on the support plate 2, the ring plate 6 is set at the end of the stator 7. The rotor 5 is installed on the rotating shaft through the rotor bracket 4. The specific structure of the rotating shaft is shown in FIG. The baffles 12 form two symmetrical circulating air ducts on the left and right sides of the rotor 5 . The rotor bracket 4 is provided with ventilation holes, the rotor 5 is provided with rotor radial ventilation holes 52 , the stator 7 is provided with stator radial ventilation holes 71 , and the outside of the stator 7 is provided with a cooler 3 . The heat source of the doubly-fed wind generator is mainly the stator winding, the rotor winding and the rotor core. The cooling air enters the motor from the air inlet 14 of the motor frame, and then passes through the ventilation holes on the rotor bracket 4, the rotor axial ventilation holes 51, The radial ventilation holes 52 of the rotor, the air gap 11 between the stator and the rotor, and the radial ventilation holes 71 of the stator enter the cooler 3 for heat exchange.

This embodiment of the cooling ventilation system includes at least one wind deflector 1. The wind deflector 1 includes an annular portion 110 and an arc portion 120 extending from the inner peripheral surface of the annular portion 110. For the specific structure, please refer to the embodiment of the air deflector. , the utility model will not go into details here. The shroud 1 is arranged at the end of the rotor 5 and is sleeved in the ring plate 6 , and its ring portion 110 is fixedly connected with the ring plate 6 . Wherein, the shroud 1 is streamlined, which can effectively reduce resistance and loss. The shroud 1 is arranged at the end of the rotor 5, and uses the wind pressure generated by the radial ventilation holes 52 of the rotor 5 to drive the fluid to move. The circulation process is: the fluid flowing through the arc portion 120 of the shroud 1, driven by the wind pressure at the end of the rotor 5, passes through the rotor bracket 4, the rotor axial ventilation holes 51, the rotor radial ventilation holes 52, and the rotor in sequence. 5, the air gap 11 between the stator 7 and the stator radial ventilation hole 71 reach the back of the stator 7 (the side away from the rotor shaft), take away the heat in the rotor 5 and the stator 7, and then enter the cooler 3 for cooling. For heat exchange, the cold air after heat exchange from the cooler 3 enters the shroud 1 again from the air inlet 14 of the motor frame, and a cycle is completed so far. In this embodiment, when the fluid flows through the shroud 1, the resistance can be reduced, the loss can be reduced, and the fluid can maintain better flowability and higher pressure head; at the same time, when the rotor 5 rotates, its radial ventilation holes 52 The wind pressure generated at the end of the rotor 5 can drive the cooling air flowing out from the shroud 1 into the ventilation holes on the rotor bracket 4, and no additional axial fans are required, which simplifies the system structure. Those skilled in the art should understand that the cooling effect of this embodiment is directly related to the rotational speed of the rotor 5. The higher the rotational speed of the rotor 5, the greater the wind pressure generated by the rotor radial ventilation holes 52 at the end of the rotor 5, and the cooling air circulates. The faster the speed, the better the cooling effect on the stator and rotor.

Preferably, referring to FIG. 2 , the radius of the radial section of the second end of the shroud 1 is smaller than or equal to the minimum radius of the radial section of the rotor winding. At this time, the distance from the second end of the arc portion 120 of the shroud 1 to the rotor shaft is less than or equal to the minimum distance from the rotor winding to the rotor shaft. The purpose of such setting is to make the cooling air better enter the rotor axial ventilation hole 51 .

Preferably, referring to FIG. 2 , a support plate ventilation hole 21 is provided on the support plate 2 , and the setting of the support plate ventilation hole 21 can form a cooling air path at the end of the stator and rotor to achieve the purpose of cooling the end of the stator and rotor. The cycle process is as follows: after the cooling air flows through the shroud 1, part of the cooling air flows into the cavity 8 at the end of the stator and rotor windings, and then passes through the cavity 9 at the end of the stator and the ventilation holes 21 of the support plate to reach the cavity of the stator 7. back, and the fluid flowing out from the radial vent holes 71 of the stator joins and then enters the cooler 3 . The setting of the ventilation holes 21 on the support plate can effectively cool the end windings of the stator and rotor, so that the heat exchange of the end windings is more sufficient. At the same time, the setting of the ventilation holes 21 on the support plate can also effectively reduce the Reynolds number, and the flow field tending to laminar flow reduces the eddy current loss, and greatly exerts the role of the end of the rotor as a pressure head element. It should be noted that the diameter and number of the ventilation holes 21 of the support plate can be determined according to actual needs, and the present invention does not make any limitation thereto. Further preferably, the ventilation holes 21 of the support plate are evenly distributed along the circumference of the support plate 2 , and the uniform distribution can make the fluid flow evenly along the circumference of the support plate 2 , reducing eddy current and loss.

In a specific implementation, the distance from the annular portion 110 of the shroud 1 to the end of the stator close to the annular portion 110 may be 50-100 mm. The ring plate 6 is provided with a connection hole (not shown in the figure), and the bolt 10 passes through the connection hole and the connection hole 130 on the wind deflector 1 to fix the wind deflector 1 on the ring plate 6 .

During specific implementation, one wind deflector 1 may be arranged at one end of the rotor 5 , or one wind deflector 1 may be respectively disposed at both ends of the rotor 5 . When the shrouds 1 are installed on both sides of the rotor 5, the cooling gas circulation mode on both sides is the same, and one side is taken as an example for description below.

As shown in Figure 2, the cooling air circuit is: the cooling air flows out from the air outlet at the end of the cooler 3, and reaches the motor body through the air inlet 14 of the motor frame, and the air flows through the shroud 1 and is divided into two paths; After flowing through the ventilation holes on the rotor bracket 4, the rotor axial ventilation holes 51, the rotor radial ventilation holes 52, the air gap 11 between the stator and the rotor, and the stator radial ventilation holes 71, they reach the back of the stator 7; The cavity 8 at the end of the stator and rotor winding, the cavity 9 at the end of the stator, and the ventilation hole 21 of the support plate reach the back of the stator 7; the above two fluids converge after reaching the back of the stator 7, enter the cooler 3 for heat exchange, and then again Enter the motor body for the next cooling cycle.

Compared with the prior art, the utility model has the following advantages: the utility model does not need to be provided with an axial flow fan, a fan base and a baffle plate, but installs a shroud at the end of the stator and rotor (the distance from the end of the winding is within 10 minutes. within the allowable range of the electrical distance), and open the support plate ventilation holes on the support plate, and when the rotor rotates, the wind pressure generated by the radial ventilation holes at the end of the rotor drives the fluid to reach the inside and end of the stator winding. The heat exchange avoids the eddy current loss caused by the collision with the fluid generated from the end of the rotor, makes a series of irregular stray flows tend to be orderly, and improves the air volume of the system. In addition, since the support plate has ventilation holes on the support plate, the flow guide effect at the end of the stator and rotor is increased, so that the fluid cooled at the end of the stator can smoothly reach the back of the stator and then enter the cooler for heat exchange. In addition, the setting of the ventilation holes on the support plate also increases the overflow of the motor body, and the planar binary flow at the end tends to a slowly changing flow field, which reduces losses and improves the reliability of the system operation due to the cancellation of the axial flow fan.

Double-fed wind turbine embodiment:

The utility model also provides a doubly-fed wind power generator. The generator is provided with a cooling and ventilation system, and its specific structure can be referred to the above description, which will not be repeated in the utility model.

Since the cooling ventilation system has the above-mentioned effects, the doubly-fed wind generator with the cooling ventilation system also has the same technical effect.

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included in the Within the protection scope of the present utility model.

Claims (9)

1. A wind deflector, characterized in that the wind deflector comprises an annular portion (110) and an arc portion (120) extending along the inner circumferential surface of the annular portion (110); wherein The radial section of the arc portion (120) is circular, and the inner diameter of the circular portion is from the first end of the arc portion (120) to the second end of the arc portion (120). ends gradually decrease. 2. The wind deflector according to claim 1, characterized in that, the annular portion (110) and the arc portion (120) are integrally formed. 3. A cooling and ventilation system for a wind-driven generator, the wind-driven generator comprising a ring plate (6) and a support plate (2) for supporting the ring plate (6), characterized in that the cooling and ventilation system Including a shroud (1) arranged at least at one end of the rotor (5); wherein The shroud (1) includes an annular portion (110) and an arc portion (120) extending along the inner peripheral surface of the annular portion (110); wherein the radial section of the arc portion (120) is an annular shape, and the inner diameter of the annular shape gradually decreases from the first end of the arc portion (120) to the second end of the arc portion (120); The shroud (1) is sheathed in the ring plate (6) and is fixedly connected with the ring plate (6). 4. The cooling ventilation system according to claim 3, characterized in that, the annular portion (110) and the arc portion (120) are integrally formed. 5. The cooling ventilation system according to claim 4, characterized in that, the support plate (2) is provided with a support plate ventilation hole (21). 6. The cooling ventilation system according to claim 5, characterized in that, the ventilation holes (21) of the support plate are evenly distributed along the circumferential direction of the support plate (2). 7. The cooling ventilation system according to any one of claims 3-6, characterized in that, the radius of the radial section of the second end of the arc portion (120) is smaller than or equal to the minimum radius of the radial section of the rotor winding. 8. The cooling ventilation system according to claim 7, characterized in that, the distance from the annular portion (110) of the wind deflector (1) to the end of the stator close to the annular portion (110) is 50-100 mm. 9. A doubly-fed wind power generator, characterized in that it is provided with the cooling ventilation system according to any one of claims 3-8.

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