FIELD

The present application relates to the technical field of cooling, and in particular to a cooling system.

BACKGROUND

Wind energy is an open and safe renewable energy, and more and more attention is paid to the utilization of wind energy. As the most core equipment of wind power generation, the wind turbine is developing in the trend of being large-scale and more economical. With the increase of the capacity of a single unit, the loss of the entire wind turbine is also increasing. Especially with the rapid development of offshore units, the maintenance difficulty of the offshore units is much greater than that of onshore units due to the special environment where they are located. Therefore, the requirements for the reliability and easy maintenance of the offshore units are also continuously increasing.

A cooling system is one of the important components of the wind turbine, which is used to effectively perform heat dissipation and cooling to heat-generating components of the wind turbine, to ensure the efficient and stable operation of the wind turbine. Therefore, the improvement of the reliability of the cooling system is an important guarantee for the normal operation of the wind turbine.

However, the conventional cooling system can no longer meet the requirements of reliability, so a novel cooling system is required to be provided.

SUMMARY

In view of this, an object according to the present application is to provide a novel cooling system, to solve the problem that the conventional cooling system cannot meet the requirements of reliability.

According to one aspect of the present application, a cooling system is provided, which includes a heat exchange module, including at least a first passage and a second passage which are independent of each other; a first cooling circuit, connected to the first passage of the heat exchange module; and a second cooling circuit, connected to the first passage of the heat exchange module; where a first coolant in the first cooling circuit and/or a second coolant in the second cooling circuit is configured to flow through the first passage of the heat exchange module, to exchange heat with a third coolant which flows through the second passage of the heat exchange module.

According to the cooling system of the present application, with the arrangement of two cooling circuits, the reliability of the cooling system is improved. Therefore, the shutdown problem of the wind turbine can be reduced when the cooling system is applied to the wind turbine, and thus the availability of the wind turbine can be improved. In addition, according to the cooling system of the present application, with the arrangement of the heat exchange module having the heat exchange fins, the cooling efficiency of the cooling system can be further improved. In addition, according to the cooling system of the present application, the layout of the fault-tolerant structure of the two cooling circuits is simple and compact, which is easy to be implemented and maintained in a limited space. In addition, according to the cooling system of the present application, a reasonable component layout can be realized according to the cooling logic and technological requirements of the component to be cooled.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present application will become clearer through the following description of the embodiments in conjunction with the drawings. In the drawings:

FIG. 1 is a schematic block diagram of a cooling system according to a first embodiment of the present application;

FIG. 2 is a schematic block diagram of a cooling system according to a second embodiment of the present application;

FIG. 3 is a schematic block diagram of a cooling system according to a third embodiment of the present application; and

FIG. 4 is a schematic block diagram of a cooling system according to a fourth embodiment of the present application.

Reference numerals in the drawings:

1

circulating pump,

2

liquid inlet pipeline,

3

first temperature sensor,

4

first on-off valve,

5

first pressure transmitter,

6

first filter,

7

second pressure transmitter,

8

first heat exchanger,

8
a

first liquid inlet,

8
b

first liquid outlet,

8
c

second liquid inlet,

8
d

second liquid outlet,

8′
second heat exchanger,
8′a

first liquid inlet,

8′b

first liquid inlet,
8′c

second liquid inlet,

8′d

second liquid inlet,

9

third pressure transmitter,

10

second temperature sensor,

11

regulating valve,

12

liquid outlet pipeline,

13

third on-off valve,

14

third temperature sensor,

15

third coolant return pipeline,

16

sixth pressure transmitter,

17

fourth pressure transmitter,

18

third coolant supply pipeline,

19

second filter,

20

second on-off valve,

21

fifth pressure transmitter,

22

connecting pipeline,

23

three-passage heat exchanger,

24

liquid inlet header pipe,

25

liquid outlet header pipe,

26

check valve.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present application are described in detail with reference to the accompanying drawings. Examples of the embodiments are illustrated in the drawings, where same reference numerals represent same assemblies.

At present, a conventional small-capacity direct-drive wind turbine has relatively small load capacity and relatively few heat-generating components, especially for an onshore unit, due to the limitation of space layout and the consideration of cost, the unit generally operates with a single cooling system. When the cooling system fails, the wind turbine needs to be shut down to deal with the problem. With the increase of capacity of the single unit, the loss of heat-generating components of the wind turbine increases and the number of heat-generating components increases, so it is necessary to improve the reliability of the cooling system. However, for a single cooling system, once a failure occurs, the maintenance cost of the entire wind turbine and the loss of power generation will be increased.

Especially for an offshore unit, which is difficult to maintain, moreover, the number of components with heat dissipation demands has increased, the control process and logic of the components are different, and hence the requirements for the fault-tolerant structure and system layout are also different. In addition, with the continuous increase of the capacity of the unit, the loss of the unit itself increases. All the heat-generating components such as a generator, a shafting, a pitch controller, a nacelle cabinet, a nacelle, a converter cabinet, a transformer and so on need to be distributed with a predetermined cooling capacity to realize normal operation. Therefore, the composition of the cooling system is becoming more and more complex, and the number of cooling systems is increasing, and hence the cooling system needs to be implemented through different forms of fault-tolerant layout.

Therefore, based on the above demands, a novel cooling system is provided according to the present application, which can realize a reasonable layout of components according to the requirements of cooling logic and technology requirements of the components to be cooled. In addition, the cooling system employs a redundancy design with dual circuits as backup for each other, thus improving the reliability of the cooling system.

The cooling system is connected to the component to be cooled through two independent cooling circuits, and only heat is transferred between the two cooling circuits without mass transfer. Moreover, for different end structures of the component to be cooled, different connecting forms may be used by the cooling system, which can be adapt to and meet the requirements of different end structures. In a case that one of the two cooling circuits fails, the other cooling circuit can be started to work, so as to realize fault-tolerant operation of the two cooling circuits. Therefore, with this cooling system, fault tolerance of the cooling system can be realized under the condition that the requirements of heat dissipation of the component to be cooled are satisfied, thereby improving the reliability of the cooling system. When the cooling system is applied to the wind turbine, it can ensure that the wind turbine still operates normally without shutdown when one cooling system fails, thereby reducing the loss of power generation.

The cooling system includes a heat exchange module, a first cooling circuit and a second cooling circuit, and the coolants in the first cooling circuit and the second cooling circuit can exchange heat with a coolant of a heat source to be cooled (such as the heat-generating component in the wind turbine) in the heat exchange module. Herein, for convenience of description, the coolants in the first cooling circuit and the second cooling circuit are referred to as a first coolant and a second coolant respectively, and the coolant which directly absorbs heat from the heat source is referred to as a third coolant.

The heat exchange module includes at least a first passage and a second passage which are independent of each other, the first cooling circuit is connected to the first passage of the heat exchange module, and the second cooling circuit is connected to the first passage of the heat exchange module. The first coolant in the first cooling circuit and/or the second coolant in the second cooling circuit can flow through the first passage of the heat exchange module, so as to exchange heat with the third coolant which flows through the second passage of the heat exchange module.

In this way, the third coolant can be cooled by exchanging heat with the first coolant and/or the second coolant respectively. In addition, the first cooling circuit and the second cooling circuit can operate independently, once one of the cooling circuits fails, the other can be started at any time. Therefore, fault-tolerant operation of the cooling system is realized, thus ensuring the normal operation of the wind turbine without shutdown. Of course, the cooling system according to the present application is not limited to be applied to wind turbines, it can also be applied to various components to be cooled of other assembly systems.

The specific configuration of the cooling system according to the present application is described hereinafter with reference to FIGS. 1 to 4.

FIG. 1 is a schematic block diagram of a cooling system according to a first embodiment of the present application;

As shown in FIG. 1, the cooling system includes a first cooling circuit located at a left side, a second cooling circuit located at a right side, and a heat exchange module which includes a first heat exchanger 8 and a second heat exchanger 8′. The configurations of the first cooling circuit and the second cooling circuit may be substantially the same, and the configurations of the first heat exchanger 8 and the second heat exchanger 8′ may also be substantially the same.

Each of the first heat exchanger 8 and the second heat exchanger 8′ at least includes a first passage and a second passage which are independent of each other, the first coolant in the first cooling circuit can flow through the first passage of the first heat exchanger 8, so as to exchange heat with the third coolant in the second passage of the first heat exchanger 8. The second coolant can flow through the first passage of the second heat exchanger 8′, so as to exchange heat with the third coolant in the second passage of the second heat exchanger 8′. That is, the first coolant and the second coolant can exchange heat with the third coolant in the first heat exchanger 8 and the second heat exchanger 8′ respectively. When one of the first cooling circuit and the second cooling circuit fails, the other cooling circuit can continue operating, thus realizing non-stop operation. The first cooling circuit and the second cooling circuit may adopt full-load fault tolerance (one for use and the other one for standby), or full-load operation may be realized by the two circuits operating together.

Since the configurations of the first cooling circuit and the first heat exchanger 8 and connection between the first cooling circuit and the first heat exchanger 8 are similar to the configurations of the second cooling circuit and the second heat exchanger 8′ and connection between the second cooling circuit and the second heat exchanger 8′, the first cooling circuit and the first heat exchanger 8 are described hereinafter as an example.

As shown in FIG. 1, the first cooling circuit may include a circulating pump 1, where an outlet of the circulating pump 1 is connected to a first end (specifically, a first liquid inlet 8a) of the first passage of the first heat exchanger 8 through a liquid inlet pipeline 2, and a second end (specifically, a first liquid outlet 8b) of the first passage of the first heat exchanger 8 is connected to the circulating pump 1 through a liquid outlet pipeline 12. In this way, the first coolant can circulate in the first cooling circuit under the action of the circulating pump 1. A first heat dissipater 27 may be further provided in the first cooling circuit, so as to cool the first coolant. The first heat dissipater 27 may be an air-cooled heat dissipater.

The first coolant exchanges heat with the third coolant in the first heat exchanger 8, and the third coolant circulates in the second passage of the first heat exchanger 8, a third coolant supply pipeline 18 and a third coolant return pipeline 15. A first end of the third coolant supply pipeline 18 is connected to a first end (specifically, a second liquid inlet 8c) of the second passage of the first heat exchanger 8, and a first end of the third coolant return pipeline 15 is connected to a second end (specifically, a second liquid outlet 8d) of the second passage of the first heat exchanger 8. The third coolant can flow into the second passage of the first heat exchanger 8 through the third coolant supply pipeline 18 after absorbing heat from a heat source device, and can flow back to the heat source device through the third coolant return pipeline 15 after exchanging heat with the first coolant, so as to continuously cool the heat source device.

Specifically, under the action of the circulating pump 1, the first coolant enters the first passage of the first heat exchanger 8 through the liquid inlet pipeline 2 while the third coolant enters the second passage of the first heat exchanger 8 through the third coolant supply pipeline 18, and thus heat exchange between the first coolant and the third coolant can be realized in the first heat exchanger 8. Preferably, the first coolant and the third coolant may flow reversely in the first heat exchanger 8. After the heat exchange is completed, the first coolant flows, under the action of the circulating pump 1, back to the first heat dissipater 27 through the liquid outlet pipeline 12 after flowing through the first passage of the first heat exchanger 8, and then re-enters the first passage of the first heat exchanger 8 after being cooled by the first heat dissipater 27, to perform next circulation. The third coolant flowing through the second passage of the first heat exchanger 8 can flow back to the heat source device through the third coolant return pipeline 15 under the action of a power source.

Optionally, the liquid inlet pipeline 2 may be provided with a first filter 6. For example, the first filter 6 may be arranged between the circulating pump 1 and the first liquid inlet 8a of the first heat exchanger 8, so as to improve the cleanliness of the first coolant flowing into the first heat exchanger 8, thereby avoiding pipe blockage. In addition, a first pressure transmitter 5 may be provided at an inlet side of the first filter 6, and a second pressure transmitter 7 may be provided at an outlet side of the first filter 6, to monitor an operation state of the first filter 6. For example, the first filter 6 is required to be replaced in a case that a pressure difference ΔP1 between the first pressure transmitter 5 and the second pressure transmitter 7 reaches a preset pressure difference ΔP1. In addition, a third pressure transmitter 9 may be provided at an outlet side of the first heat exchanger 8, to monitor the blockage situation of the first passage of the first heat exchanger 8. For example, the first passage of the first heat exchanger 8 is required to be unblocked in a case that a pressure difference ΔP2 between the second pressure transmitter 7 and the third pressure transmitter 9 reaches a preset pressure difference ΔP2.

In addition, a first temperature sensor 3 may be provided in the liquid inlet pipeline 2, and a second temperature sensor 10 may be provided in the liquid outlet pipeline 12 for sensing temperatures of the first coolant entering and leaving the first heat exchanger 8, so as to get a heat exchange state between the first coolant and the third coolant based on the sensed temperatures. In addition, a first on-off valve 4 may be further provided in the liquid inlet pipeline 2, and/or, a regulating valve 11 may be provided in the liquid outlet pipeline 12. By providing the first on-off valve 4 and/or the regulating valve 11, the local pipeline can be cut off by closing the first on-off valve 4 and/or the regulating valve 11 when the cooling system is maintained or the component is replaced, thus facilitating corresponding maintenance and replacement.

Similar to the configuration of the first cooling circuit, a second filter 19 may be provided in the third coolant supply pipeline 18, so as to improve the cleanliness of the third coolant flowing into the second passage of the first heat exchanger 8. A fourth pressure transmitter 17 and a fifth pressure transmitter 21 may be provided at two sides of the second filter 19, to monitor an operation state of the second filter 19. For example, the second filter 19 is required to be replaced in a case that a pressure difference ΔP3 between the fourth pressure transmitter 17 and the fifth pressure transmitter 21 reaches a preset pressure difference ΔP3. A third temperature sensor 14 may be provided in the third coolant return pipeline 15, to adjust an opening degree of the regulating valve 11 in the first cooling circuit according to the temperature value sensed by the third temperature sensor 14, so as to ensure that the temperature of the third coolant is not lower than the temperature set according to the technological requirements of the component to be cooled during the cooling process. In addition, a sixth pressure transmitter 16 may be provided in the third coolant return pipeline 15, to monitor the blockage situation of the second passage of the first heat exchanger 8 in combination with the pressure value sensed by the fourth pressure transmitter 17. In addition, a second on-off valve 20 may be provided in the third coolant supply pipeline 18 and/or a third on-off valve 13 may be provided in the third coolant return pipeline 15, so as to cut off the local pipeline by closing the second on-off valve 20 and/or the third on-off valve 13 when the cooling system is maintained or the component is replaced, thus facilitating corresponding maintenance and replacement.

Preferably, the first heat exchanger 8 may include a plate heat exchanger, and the plate heat exchanger may include heat exchange fins. Therefore, when the first coolant exchanges heat with the third coolant, the heat exchange fins of the first heat exchanger 8 can exchange heat with the external air at the same time, so as to further enhance the efficiency of cooling the third coolant.

Similarly, the second heat exchanger 8′ may include a first liquid inlet 8′a, a first liquid outlet 8′b, a second liquid inlet 8′c and a second liquid outlet 8′d. The connections among the second heat exchanger 8′, the second cooling circuit, the third coolant supply pipeline and the third coolant return pipeline are similar to the connections among the first heat exchanger 8, the first cooling circuit, the third coolant supply pipeline and the third coolant return pipeline, which are not described herein.

FIG. 2 is a schematic block diagram of the cooling system according to a second embodiment of the present application.

The cooling principle of the second embodiment is similar to that of the first embodiment, with the difference that a connecting pipeline 22 which connects the first heat exchanger 8 with the second heat exchanger 8′ is provided in the second embodiment.

Different from the second heat exchanger 8′ in the first embodiment, as shown in FIG. 2, the second liquid inlet 8′c of the second heat exchanger 8′ in the first embodiment is used as a second liquid outlet in the second embodiment and is connected to the third coolant return pipeline 15, the second liquid outlet 8′d of the second heat exchanger 8′ in the first embodiment is used as a second liquid inlet in the second embodiment and is connected to the second liquid outlet 8d of the first heat exchanger 8 through the connecting pipeline 22, thus reducing the layout and number of the third coolant supply pipeline 18 and the third coolant return pipeline 15. That is, by providing the connecting pipeline 22, the series connection between the second passage of the first heat exchanger 8 and the second passage of the second heat exchanger 8′ is effectively realized, which reduces a path of the third coolant supply pipeline18 and a path of the third coolant return pipeline 15, and thus simplifies the layout of the pipelines.

In a case that the first heat exchanger 8 and the second heat exchanger 8′ are connected in series through the connecting pipeline 22, a first end of the third coolant supply pipeline 18 is connected to a second end (that is, a second liquid inlet 8c) of the second passage of the first heat exchanger 8, and a first end of the third coolant return pipeline 15 is connected to a second end (that is, a second liquid outlet) of the second passage of the second heat exchanger 8′. Of course, the positions of the third coolant supply pipeline 18 and the third coolant return pipeline 15 may be exchanged with each other.

The configuration and layout of other components of the cooling system are similar to the configuration and layout of components of the first embodiment, which are not described in detail herein.

With the above layout manner of the cooling system, not only the independent operation of the first cooling circuit and the second cooling circuit can be realized, thus when one of the two cooling circuits fails, the other cooling circuit is started to realize fault-tolerant operation, to ensure the cooling efficiency of the heat-generating components, but also the pipelines and components of the layout can be further simplified, which has certain advantages when a compact layout space is required.

FIG. 3 is a schematic block diagram of the cooling system according to a third embodiment of the present application.

The cooling principle of the third embodiment is similar to that of the first embodiment, with the difference that the heat exchanger module of the cooling system of the third embodiment employs a three-passage heat exchanger 23, thus the arrangement and layout of components can be further effectively simplified. After one cooling circuit in the cooling system fails, the other cooling circuit in the cooling system can still operate normally.

In the third embodiment, the three-passage heat exchanger 23 may include a first flow passage, a second flow passage and a third flow passage which are independent of one another. A first liquid inlet 23a is in communication with a first liquid outlet 23b through the first flow passage, a second liquid inlet 23c is in communication with a second liquid outlet 23d through the second flow passage, and a third liquid inlet 23e is in communication with a third liquid outlet 23f through the third flow passage. The first cooling circuit is connected to the first flow passage of the three-passage heat exchanger 23, the second cooling circuit is connected to the third flow passage of the three-passage heat exchanger 23, and the third coolant supply pipeline 18 and the third coolant return pipeline 15 are connected to two ends of the second flow passage of the three-passage heat exchanger 23 respectively. In this way, the first coolant in the first cooling circuit can flow through the first flow passage of the three-passage heat exchanger 23 and the second coolant in the second cooling circuit can flow through the third flow passage of the three-passage heat exchanger 23, so as to exchange heat with the third coolant in the second flow passage of the three-passage heat exchanger 23.

The configuration and layout of other components of the cooling system are similar to the configuration and layout of components in the first embodiment, which are not described herein.

With the above layout manner of the cooling system, not only the independent operation of the first cooling circuit and the second cooling circuit can be realized, thus when one of the two cooling circuits fails, the other cooling circuit is started to realize fault-tolerant operation, to ensure the cooling efficiency of the heat-generating components, but also the two heat exchanges are integrated into one heat exchanger, which further simplifies the pipelines and components of the layout, and thus can realize the redundant layout of the two cooling circuits in a limited space.

FIG. 4 is a schematic block diagram of the cooling system according to a fourth embodiment of the present application.

The cooling principle of the fourth embodiment is similar to that of the first embodiment, with the difference that the layout of the first cooling circuit, the second cooling circuit and the heat exchanger modules is different from the corresponding layout in the first embodiment.

As shown in FIG. 4, the first cooling circuit and the second cooling circuit are connected in parallel to be connected with the first passage of the heat exchange module. In this embodiment, the heat exchange module may be a single first heat exchanger 8 or multiple first heat exchangers 8 connected in series. The first cooling circuit and the second cooling circuit are connected with the first heat exchanger 8 in a manner that the first cooling circuit and the second cooling circuit are connected in parallel.

Specifically, the first heat exchanger 8 includes a first liquid inlet 8a, a liquid inlet header pipe 24 which is connected to the first liquid inlet 8a, a first liquid outlet 8b and a liquid outlet header pipe 25 which is connected to the first liquid outlet 8b, and the first cooling circuit and the second cooling circuit are connected in parallel between the liquid inlet header pipe 24 and the liquid outlet header pipe 25 of the first heat exchanger 8. That is, the confluence and distribution of the first cooling circuit and the second cooling circuit can be realized by the liquid inlet header pipe 24 and the liquid outlet header pipe 25. In this way, a part of pipelines of the two cooling circuits can be combined, which further simplifies the arrangement of the pipelines, thus realizing the compactness of the overall layout.

At least one of the first cooling circuit and the second cooling circuit may be provided with a check valve 26. For example, the check valve 26 may be arranged in the liquid inlet pipeline 2, which only allows one-way communication. In a case that one of the first cooling circuit and the second cooling circuit fails and stops operation, the other one of the first cooling circuit and the second cooling circuit can operate normally, and the coolant in the other cooling circuit flows into the first heat exchanger 8 through the liquid inlet header pipe 24. Since the check valve 26 is provided in the cooling circuit which is shut down due to failure, the coolant in the cooling circuit which operates normally cannot enter the failed cooling circuit, which ensures the cooling efficiency in the situation that a single small-capacity heat exchanger is provided. Therefore, fault-tolerant operation of the cooling system can be realized on the condition that the layout of the cooling system is greatly simplified.

In this embodiment, the liquid inlet pipeline 2 includes the liquid inlet header pipe 24 and pipelines connected between the circulating pump 1 and the first heat exchanger 8, and the liquid outlet pipeline 12 includes the liquid outlet header pipe 25 and pipelines connected between the circulating pump 1 and the first heat exchanger 8. In addition, in FIG. 4, the first filter 6 and the second pressure transmitter 7 are arranged in the liquid inlet header pipe 24, and the regulating valve 11 is arranged in the liquid outlet header pipe 25, but the arrangement is not limited to this. That is, the layout of the corresponding components in the first cooling circuit and the second cooling circuit can be arranged according to the actual situation, which is not limited to the example shown in the figures.

According to the cooling system of the present application, the reliability of the cooling system can be improved with the arrangement of the two cooling circuits. Therefore, when the cooling system is applied to the wind turbine, the shutdown problem of the wind turbine can be reduced, and thereby the availability of the wind turbine can be improved. In addition, according to the cooling system of the present application, the cooling efficiency of the cooling system can be further improved with the heat exchange module having the heat exchange fins being provided. In addition, according to the cooling system of the present application, the layout of the fault-tolerant structure of the two cooling circuits is simple and compact, and is easy to implement and maintain in a limited space. Moreover, according to the cooling system of the present application, a reasonable component layout can be realized according to the cooling logic and technological requirements of the component to be cooled.

Although the embodiments of the present application have been described above in detail, various modifications and variations can be made to the embodiments of the present application by those skilled in the art without departing from the spirit and scope of the present application. It should be understood by those skilled in the art that such modifications and variations still fall within the spirit and scope of the embodiments of the present application as defined by the claims.