CN215486441U

CN215486441U - Air compressor system

Info

Publication number: CN215486441U
Application number: CN202121843764.9U
Authority: CN
Inventors: 尹书涛
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2021-08-09
Filing date: 2021-08-09
Publication date: 2022-01-11
Anticipated expiration: 2031-08-09

Abstract

The present invention relates to an air compressor system comprising at least: an air compressor having a first air inlet and a first air outlet for air and a first coolant inlet and a first coolant outlet for coolant; an intercooler having a second air inlet and a second air outlet and a second coolant inlet and a second coolant outlet, the second air inlet fluidly connected to the first air outlet, wherein the first coolant outlet of the air compressor is fluidly connected to the second coolant inlet of the intercooler. The utility model also relates to a fuel cell system. A compact configuration of the air compressor system and a full utilization of the coolant can be realized cost-effectively.

Description

Air compressor system

Technical Field

The present invention relates to an air compressor system, particularly for use in a fuel cell system. The utility model also relates to a corresponding fuel cell system.

Background

With the increasing prominence of energy scarcity and environmental issues, fuel cell technology is receiving more and more attention. The fuel cell can directly convert hydrogen and oxygen in the air into water through an electrode reaction and generate electric power. The fuel cell has the advantages of high efficiency, no pollution, low noise and the like.

Air compressors are important components of air supply subsystems for fuel cell systems. The air compressor can pressurize the air supplied to the stack and accordingly provide air with a specific pressure and flow rate, thereby enabling an increase in the operating efficiency of the fuel cell while maximally overcoming the disadvantage of insufficient oxygen supply and maintaining good dynamic performance over a wide range of air flow rates.

However, under high power operating conditions of the stack, since a large amount of air needs to be compressed at a high compression ratio, the temperature of the air compressed by the air compressor may be increased to about 100 to 150 ℃. The temperature of the compressed air is greater than the normal operating temperature of the fuel cell stack, for example, about 60 to 80 ℃, which may adversely affect the humidification efficiency of the humidifier of the fuel cell and the operating efficiency of the stack. In order to protect the stack and maintain the air entering the stack at a proper temperature, an intercooler is generally additionally provided to cool the compressed air before entering the stack. The intercooler requires additional cooling ducts, which increases system complexity and limits the application of high power fuel cells in miniaturized scenarios.

SUMMERY OF THE UTILITY MODEL

It is therefore an object of the present invention to provide an improved air compressor system which, for an intercooler, avoids the provision of additional cooling lines and the introduction of additional coolant, as a result of which a compact design of the air compressor system and a sufficient utilization of the coolant can be achieved in a cost-effective manner. The utility model also aims to provide a corresponding fuel cell system.

According to a first aspect of the present invention, there is provided an air compressor system comprising at least:

-an air compressor having a first air inlet and a first air outlet for air and a first coolant inlet and a first coolant outlet for coolant;

-an intercooler having a second air inlet and a second air outlet and a second coolant inlet and a second coolant outlet, the second air inlet being fluidly connected to the first air outlet,

wherein the first coolant outlet of the air compressor is fluidly connected with the second coolant inlet of the intercooler.

According to the present invention, it is possible to introduce air compressed by the air compressor having a higher temperature into the intercooler by fluidly connecting the second air inlet of the intercooler to the first air outlet of the air compressor, and it is possible to introduce the coolant having passed through the air compressor into the intercooler and to cool the compressed air having a higher temperature again therein by fluidly connecting the first coolant outlet of the air compressor to the second coolant inlet of the intercooler. Therefore, the internal components of the air compressor and the compressed air can be cooled by fully utilizing the coolant, and the introduction of extra coolant is avoided while the effective cooling of the compressed air is realized. It is also possible to eliminate the arrangement of the additional coolant line and achieve a compact configuration of the air compressor system as a whole.

According to a second aspect of the present invention, there is provided a fuel cell system having an air compressor system according to the present invention and an electric stack, the air compressor system being configured and adapted to supply compressed air to the electric stack.

Drawings

The principles, features and advantages of the present invention may be better understood by describing the utility model in more detail below with reference to the accompanying drawings. The drawings comprise:

FIG. 1 illustrates a circuit diagram of an air compressor system according to an exemplary embodiment of the present invention;

FIG. 2 illustrates a schematic diagram of an air compressor system according to an exemplary embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and exemplary embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and do not limit the scope of the utility model.

In the drawings, the size of each component, the thickness of a layer, or a region may be exaggerated for clarity. Accordingly, the shapes and sizes of each of the elements in the drawings are not to be considered true scale.

In the description of the present invention, it is to be understood that the terms "first", "second" and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

In the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may for example be fixedly connected or detachably connected; the connection can be material locking connection, or shape locking or force locking connection; either directly or indirectly through intervening components, or may be interconnected between two elements or in a relationship wherein two elements interact, unless expressly limited otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

FIG. 1 shows a circuit diagram of an air compressor system 100 according to an exemplary embodiment of the present invention. Here, the air compressor system 100 is exemplarily configured to supply compressed air to the stack 200 of the fuel cell system, where an electrochemical reaction occurs, water is generated from hydrogen and oxygen in the air, and an electric current is generated. Of course, the air compressor system 100 is also contemplated for use in other fields where deemed appropriate by one skilled in the art.

As shown in fig. 1, the air compressor system 100 has an air compressor 10, which is, for example, configured as a centrifugal air compressor, and generates centrifugal force by rotating gas at a high speed by an impeller, and generates compressed air continuously by increasing a flow velocity and a pressure of the gas after passing through the impeller due to a diffusion flow of the gas in the impeller. Of course, other types of air compressors, such as screw air compressors, are also contemplated. Here, air in the environment enters the air compressor 10 through the first air inlet 11, and is discharged through the first air outlet 12 after being compressed. Here, the solid arrows indicate the flow path of the air.

Here, in operation of the air compressor 10, electrical energy is converted into mechanical energy, so that the rotor including the impeller rotates at a high speed around the stator, thereby compressing air. However, in this process, electrical energy is also converted into thermal energy, so that the temperature of the components of the air compressor 10, in particular the stator, rises significantly, which adversely affects the operating performance of the air compressor 10 and, in the worst case, can even lead to a shutdown. Meanwhile, the molecular kinetic energy of the compressed air is increased, and the temperature of the compressed air is obviously increased. Illustratively, the temperature of the compressed air discharged from the first air outlet 12 reaches about 150 ℃.

As shown in fig. 1, air compressor 10 has a first coolant inlet 13 and a first coolant outlet 14 for a coolant that can reduce the temperature of components, particularly the stator, inside air compressor 10 to ensure proper operation of air compressor 10. The coolant is for example water. Here, the coolant enters the air compressor 10 through the first coolant inlet 13, flows through the component to be cooled, for example, a stator, and is discharged through the first coolant outlet 14. Here, the dashed arrows indicate the flow path of the coolant.

The air compressor system 100 further comprises, exemplarily, a coolant pump 30 arranged upstream of the first coolant inlet 13 and for controlling the flow of coolant. The coolant flow can be adjusted as required by the coolant pump 30 and the temperature of the air compressor 10 can be controlled thereby.

Since the temperature of the compressed air discharged from the first air outlet 12 is high, for example, up to about 150 ℃, while the operating temperature of the stack of the fuel cell system is limited to below 100 ℃ and the optimum operating temperature is 40 to 90 ℃, an excessively high temperature may cause a decrease in the water content of the proton exchange membrane, and the electrical conductivity and the electrode reaction rate may be drastically decreased, so that the compressed air still needs to be cooled before being supplied to the stack 200.

As shown in fig. 1, air compressor system 100 has an intercooler 20 disposed between air compressor 10 and electric stack 200 and configured to cool compressed air discharged from air compressor 10.

As shown in fig. 1, the intercooler 20 has a second air inlet 21 fluidly connected to the first air outlet 12 of the air compressor 10 and a second air outlet 22 connected to the stack 200. Therefore, the compressed air discharged from the air compressor 10 flows to the stack 200 of the fuel cell system through the intercooler 20.

As shown in fig. 1, the intercooler 20 has a second coolant inlet 23 and a second coolant outlet 24, which are fluidly connected to the first coolant outlet 14 of the air compressor 10. It is thereby possible to introduce the coolant discharged from the first coolant outlet 14 of the air compressor 10 into the intercooler 20 and cool the high-temperature compressed air with the coolant. Illustratively, the temperature of the coolant discharged from the first coolant outlet 14 is about 68 ℃ and the temperature of the compressed air discharged from the first air outlet 12 is about 150 ℃, the temperature difference between the two being over 80 ℃, whereby the coolant still achieves a good cooling effect and reduces the temperature of the compressed air to below 90 ℃, in particular below 75 ℃. By connecting the second coolant inlet 23 of the intercooler 20 with the first coolant outlet 14 of the air compressor 10, it is possible to make full use of the coolant supplied to the air compressor 10 and avoid introducing additional coolant, and it is also possible to eliminate the arrangement of additional coolant lines and achieve a compact configuration of the air compressor system 100.

FIG. 2 shows a schematic diagram of an air compressor system 100 according to an exemplary embodiment of the present invention.

As shown in fig. 2, the first air outlet 12 of the air compressor 10 is connected to the second air inlet 21 of the intercooler 20, and the first coolant outlet 14 of the air compressor 10 is connected to the second coolant inlet 23 of the intercooler 20. In this case, air in the environment enters the air compressor 10 through the first air inlet 11, enters the intercooler 20 through the first air outlet 12 and the second air inlet 21 after being compressed, and the coolant enters the air compressor 10 through the first coolant inlet 13 and enters the intercooler 20 through the first coolant outlet 14 and the second coolant inlet 23, where the coolant cools the compressed air.

Illustratively, the second coolant inlet 23 is joined directly to the first coolant outlet 14. This saves piping or hoses and makes the air compressor system 100 compact. In this case, the second coolant inlet 23 can be welded to the first coolant outlet 14, so that a fixed, sealed connection is achieved. However, other connection means which are considered to be expedient by the person skilled in the art, such as, for example, a threaded connection with a sealing washer, are also conceivable.

Illustratively, the intercooler 20 is integrated into the air compressor 10 by a fixed connection between the second coolant inlet 23 and the first coolant outlet 14. Thereby simplifying the assembly process.

Illustratively, the second air inlet 21 is connected to the first air outlet 12 by a conduit 40. By providing the line 40, the position of the second air inlet 21 and the first air outlet 12 can be selected more flexibly and the configuration of the air compressor system 100 can be adapted more flexibly. In particular, a hose can be used as the line 40.

The second air inlet 21 may also, for example, be joined directly to the first air outlet 12. This eliminates the line 40 and makes the air compressor system 100 more compact.

Illustratively, the intercooler 20 has an air passage through which compressed air flows and a coolant passage through which coolant flows, which are independent of and adjacent to each other. This enables good cooling of the compressed air. Here, the air channel and the coolant channel are exemplarily configured in a zigzag shape, thereby increasing a heat exchange area of the compressed air and the coolant.

The intercooler 20 is manufactured in one piece from aluminum, for example. Of course, other materials having good thermal conductivity are also contemplated for the intercooler 20.

Exemplarily, a temperature sensor 25 is provided at the second air outlet 22 of the intercooler 20, and is configured to detect a temperature of the compressed air discharged from the second air outlet 22. Here, when the temperature of the compressed air is higher than a predetermined value, the flow rate of the coolant may be increased by adjusting the coolant pump 30, for example, so that the temperature of the compressed air is reduced to be within a desired range.

The preceding explanations of embodiments describe the utility model only in the framework of said examples. Of course, the individual features of the embodiments can be freely combined with one another as far as technically expedient, without departing from the framework of the utility model.

Other advantages and alternative embodiments of the present invention will be apparent to those skilled in the art. Therefore, the utility model in its broader aspects is not limited to the specific details, representative structures, and illustrative examples shown and described. On the contrary, various modifications and substitutions may be made by those skilled in the art without departing from the basic spirit and scope of the utility model.

Claims

1. An air compressor system (100) comprising at least:

-an air compressor (10) having a first air inlet (11) and a first air outlet (12) and a first coolant inlet (13) and a first coolant outlet (14);

-an intercooler (20) having a second air inlet (21) and a second air outlet (22) and a second coolant inlet (23) and a second coolant outlet (24), the second air inlet (21) being fluidly connected to the first air outlet (12),

characterized in that the first coolant outlet (14) of the air compressor (10) is in fluid connection with the second coolant inlet (23) of the intercooler (20).

2. The air compressor system (100) of claim 1, wherein the second coolant inlet (23) is directly joined to the first coolant outlet (14).

3. The air compressor system (100) of claim 1 or 2, wherein the intercooler (20) is integrated onto the air compressor (10) through a fixed connection between the second coolant inlet (23) and the first coolant outlet (14).

4. The air compressor system (100) of claim 1 or 2, wherein the intercooler (20) has an air passage and a coolant passage that are independent and adjacent to each other.

5. The air compressor system (100) of claim 1 or 2, wherein the intercooler (20) is integrally manufactured from aluminum.

6. The air compressor system (100) of claim 1 or 2, wherein a temperature sensor (25) is provided at the second air outlet (22) of the intercooler (20).

7. The air compressor system (100) of claim 1 or 2, wherein the air compressor system (100) further comprises a coolant pump (30) arranged upstream of the first coolant inlet (13) and configured to control a flow of coolant.

8. The air compressor system (100) of claim 1 or 2, wherein the second air inlet (21) is connected to the first air outlet (12) by a conduit (40); or

The second air inlet (21) is joined directly to the first air outlet (12).

9. The air compressor system (100) of claim 1 or 2, wherein the air compressor (10) is configured as a centrifugal compressor.

10. A fuel cell system having an air compressor system (100) according to any one of claims 1 to 9 and a stack (200), the air compressor system being configured and adapted to supply compressed air to the stack.