WO2003083313A1

WO2003083313A1 - Compressor unit

Info

Publication number: WO2003083313A1
Application number: PCT/EP2003/003273
Authority: WO
Inventors: Rudi Dittmar; Peter Fischer
Original assignee: Nash_Elmo Industries Gmbh
Priority date: 2002-03-28
Filing date: 2003-03-28
Publication date: 2003-10-09
Also published as: DE10214307A1; AU2003224009A1

Abstract

The invention relates to a compressor unit (1) for a gaseous medium (3), comprising at least one compressor (5) and a drive unit (7) that is coupled thereto, at least one inlet (9) for the gaseous medium (3), and at least one outlet (11) for the gaseous medium (3). The aim of the invention is to supply a compact compressor unit in which the temperature of the compressed gaseous medium can be influenced in a simple manner. Said aim is achieved by a guiding system (13) for the gaseous medium (3), which is arranged between one outlet (12) of the compressor (5) and the outlet (11) of the compressor unit (1).

Description

description

Nerdichtereinheit

The invention relates to a ner poet unit according to the preamble of claim 1.

Compressor units of this type, in particular for compressing gaseous media, are known, for example, from the document “Siemens Energietechnik, special issue pumps and compressors (publisher and publisher: Siemens AG, Berlin / Munich; Siemens Energietechnik 7 (1985)). The compressor unit has at least one compressor, a drive unit through which the compressor can be driven, at least one inlet and at least one outlet each for the gaseous medium such as air, oxygen, nitrogen, etc. The gaseous medium is compressed by the compression within such a compressor unit. According to the thermodynamic laws, the compressed medium is heated. High temperatures can occur during heating. The compressed gaseous medium is usually fed to a subsequent unit. If the subsequent unit for the gaseous medium provides a certain temperature range in which the gaseous medium must be located, the compressed medium is unsuitable for the subsequent unit because of a temperature outside the permissible temperature range. The subsequent unit can be a chemical process step, for example. Compressed gaseous media can be used in a variety of ways, such as in chemistry, physics or electrical engineering. For fuel cells, for example, compressed air is required which does not exceed a certain temperature. Conventional compressors are therefore unsuitable for fuel cells, for example, because the compressed air escaping, ie the _. gaseous medium, too high a temperature. Since gaseous media can occur in some chemical processes even at very low temperatures, which have to be compressed in a compressor in order to be used for further use, but which require a minimum temperature of the compressed gaseous medium, previous compressor units cannot be used, if the temperature rise between an inlet of the compressor and an outlet of the compressor unit is too small.

To use previous compressors in the cases mentioned above, additional devices are always necessary which bring about a certain temperature of the compressed gaseous medium, i.e. either a temperature increase or a temperature reduction.

The object of the invention is to provide a compact compressor unit in which the temperature of the compressed gaseous medium can be influenced in a simple manner.

The object is achieved according to the invention by a compressor unit for a gaseous medium, which has at least one compressor and a drive unit coupled to it, at least one inlet for the gaseous medium and at least one outlet for the gaseous medium

Guide system for the gaseous medium, is arranged between an outlet of the compressor and the outlet of the compressor unit.

The compression process within the compressor changes the pressure of the gaseous medium as well as the temperature in accordance with the thermodynamic laws. So far, the output of the compressor forms from the outlet of the compressor unit. The guide system according to the invention separates the outlet of the compressor from the outlet of the compressor unit, at least by the guide system. This alone already results in a Flow of the gaseous medium through the guide system. The influencing results among other things from the fact that the kinetic energy of the gaseous medium is changed by the guide system. Another influence arises from the delivery of thermal energy of the gaseous medium via the guide system. The thermal energy is released in a simple manner by convection. In addition, the thermal energy delivery is forced through a device for energy delivery.

The compressor unit for compressing gaseous media, which has at least one compressor, a drive unit through which the compressor can be driven and has at least one inlet and at least one outlet for the medium, is thus designed such that the gaseous medium is at least partially between the compressor and the outlet can be guided by a guide system, the guide system being placed in a thermally conductive contact with a temperature-influencing medium, such as a cooling medium, by a device for influencing the temperature. The device for influencing the temperature is furthermore in direct thermal contact with the drive unit for dissipating heat loss.

The compressor unit is preferably designed in such a way that the guide system runs at least partially within the temperature influencing device which contains the temperature influencing medium.

The device for influencing the temperature is, for example, a device for air cooling and / or also a device for liquid cooling. The temperature influencing medium is consequently e.g. Air and / or a liquid.

If the drive unit of the compressor module is an electric motor, this can be a self-ventilated motor. With the cooling air of the self-ventilated engine, which at least partially stroking the guide system, it is possible to influence and cool the temperature of the gaseous medium compressed by the compressor. The device for influencing the temperature then also has at least one fan. The guide system also belongs, at least in part, to the device for influencing the temperature. The device for influencing temperature is to be understood as meaning those parts which are required for influencing the temperature. If a fan is used, it is a self-ventilator or an external ventilator, as with a forced-ventilation motor.

The device for influencing the temperature can also be designed as a device with a liquid as the temperature-influencing medium. In one embodiment, the temperature-influencing medium acts as a cooling liquid. If the guidance system runs at least partially in the liquid, then thermal energy can be released to the liquid or can also be absorbed by it. In this case, the device for influencing the temperature has at least one means which absorbs the liquid for influencing the temperature. This means is, for example, a tube or a container, such as a type of closed trough, in which the guide system is also at least partially located. In the case of pipes, pipes can also be guided into one another - pipe inside the pipe - whereby the temperature-influencing medium runs in one pipe and the compressed gaseous medium is transported in another pipe (guide system). Even with a liquid temperature-influencing medium, this enables simultaneous cooling of the drive unit (e.g. electric motor).

The device for influencing the temperature can have two cooling directions depending on the type of use. If the emerging compressed gaseous medium, such as air, is to be cooled, the cooling effect of the device for temperature Door influence on the compressed gaseous medium. If the compressed gaseous medium is very cool and should therefore be heated, the heating can be caused by the heat losses of the drive unit. This results in a cooling effect of the device for influencing the temperature with respect to the drive unit, which is, for example, an electric motor.

Advantageously, the gaseous medium is thus separated by the liquid used for cooling, e.g. Cooling water, heatable.

In a further advantageous embodiment, the liquid cools the gaseous medium.

In many areas of technology, for example in vehicle construction, compressor assemblies with high power density, ie small construction volumes and low weight with high compression performance, are desired. Further requirements with regard to such compressor units, ie compressor units, are, for example, a low noise level, a controllable speed, low exhaust air temperature and / or a high degree of freedom from maintenance. Compressor units are becoming increasingly important, particularly when it comes to the self-sufficient energy supply of vehicles at a standstill, so that devices such as air conditioning, heating, radio equipment, etc. can still be operational. This is made possible for example by Brennsto fzellensysteme, ^■ which are preferably compact build because of the small space. Compressor systems are required to operate fuel cell systems of this type, which are advantageously also specially optimized for these applications. The requirements of the fuel cell systems are to be met by a compressor unit constructed according to the invention. The compressor unit itself is driven, for example, by a drive unit, such as an asynchronous motor, a synchronous motor, a reluctance motor or other motor types. Such motors are preferably fed by a converter. In an advantageous embodiment of the compressor unit, such a compressor unit consequently also has a converter which feeds the drive unit. This also accommodates a compact structure.

Both the drive unit and the converter itself generate heat loss during operation. Thanks to the device for influencing the temperature, it is now possible in a simple manner to additionally cool the converter. Of course, it is also possible not only to remove the waste heat, but also to use it. Good cooling is particularly advantageous due to the low thermal capacity of converters compared to motors. Not only the lifespan, but also the power density can be increased in this way.

To power the drive unit, i.e. of a motor, air-cooled converters can also be used in addition to water-cooled converters. A ^ .ch the engine is air-cooled as a drive unit. In an advantageous embodiment, the motor is self-ventilated. The motor's own ventilation can also be used to cool the converter. In addition to the cooling of the converter, the self-ventilation of the motor also allows the compressed gaseous medium to be cooled by the cooling air passing the guide system in which the compressed gaseous medium is located. One advantage of air-based devices for influencing temperature is their robustness.

In an advantageous embodiment of the invention, the device for influencing the temperature is designed at least as a partial casing of the compressor unit, the partial casing receiving a water bath and at least parts of the cooling system running in the water bath. Water cooling is a particularly effective way of cooling. If the cooling system now has a water bath which is formed at least in a partial casing of the compressor unit, the guide system of the compressed gaseous medium can run at least partially therein, so that the compressed gaseous medium is cooled by such an arrangement. Since the heat capacity of the water is limited, it is advantageous to replace the water that has already been heated. This requires a water outlet and a water inlet. Of course, this also applies to other liquids, the water is only an example of a liquid. When selecting the liquid, environmental conditions must always be taken into account, so that, for example, the use of deionized water may also be necessary.

In a further embodiment of the compressor unit, the device for influencing the temperature has cooling coils as a guide system, which run in a spiral around the drive unit. The round design of motors is used.

If the compressor unit has a housing which functions as a casing and has a rectangular outer contour, the cooling coils of the device for influencing the temperature, which act as a guide system, advantageously run in the corners of the housing, which is thus all the more compact. The course in the corners of the housing is advantageous because this area is otherwise unused due to the round design of the motors. As a replacement or supplement to a water bath, a special heat exchanger can also be provided as a device for influencing the temperature, and consequently also as a cooling device. Such a heat exchanger allows heat energy from the compressed medium to be released to the liquid for cooling. Because of the cylindrical design of motors, a disc-shaped heat exchanger can be easily integrated into the compressor unit. The disk-shaped heat exchanger has a surface which faces the converter, which has at least one power semiconductor component on a carrier plate, or is at least thermally conductively connected to the carrier plate. Power semiconductor components are the components within a converter that emit a particularly large amount of thermal energy and are sensitive to excessive temperatures with failure. IGBTs are an example of this. For this reason, the power semiconductor components are cooled in a combined device for influencing the temperature together with the compressed gaseous medium.

The compressor unit is constructed, for example, as a side channel compressor. Side channel compressors, like other compressors, can also be built up from different compressors, whereby this includes both a parallel connection of compressors and a series connection of compressors, which together again form a compressor.

Various configurations of the invention can be found in the subclaims.

To further explain the invention, reference is made to the drawing, in which embodiments of the compressor unit or parts thereof are illustrated schematically. Show it:

1 shows a compressor unit with converter motor and compressor in a water bath,

2 shows a compressor unit with a motor and compressor in a water bath,

3 shows a connection side of a compressor unit, 4 shows a longitudinal section through a compressor unit,

5 shows a further longitudinal section through a compressor unit,

6 shows a three-dimensional representation of a spiral-shaped guide system,

7 shows a three-dimensional longitudinal view of parts of a compressor unit,

8 shows a detail of a longitudinal view of a compressor unit, and

9 shows a connection side of a compressor unit.

The illustration according to FIG. 1 shows a compressor unit 1 which has a casing 23, which can also be designed as a housing for the compressor unit 1. Inside the shell

23 there is a power converter 19, followed by a drive unit 7 and a compressor 5. Since the illustration is a longitudinal section through the compressor unit 1, there are cuts with respect to a guide system 13. The guide system 13 has tubes, in which a gaseous medium 3 can be guided, the direction of guidance being partially identified by circles with a point or a cross. The guide system 13 is fed via an outlet 12 of the compressor 5. The compressor 5 is located together with the drive unit 7 and the converter 19 within a liquid 17 which fills up the space between the casing 23 and the elements just described. The guide system 13 runs within the liquid 17, thermal energy being exchangeable between the gaseous medium 3 and the liquid 17, which forms a water bath 25. Advantageously, not only the compressed gaseous medium, which runs through the guiding system 13, is cooled, but also the drive unit 7 and the converter 19. The guiding system 13 can be constructed in such a way that only the compressed gaseous medium 3 is in heat exchange with the liquid 17, or that the gaseous medium which has not yet been compressed Medium is in heat exchange with the liquid 17, and / or that a combination results.

The illustration according to FIG. 2 shows a compressor unit 1 similar to that in FIG. 1, but the inlet or outlet of the gaseous medium 3 is indicated schematically in this figure. Arrows also schematically sketch the entry or exit of the liquid from the water bath. Reference number 9 indicates the inlet and reference number 11 the outlet for the gaseous medium 3. The outlet 12 of the compressor unit 1 is one end of the guide system 13 and the outlet 12 of the compressor 5 is the other end of the guide system 13. In comparison to FIG. 1, the converter in FIG. 2 is located outside the liquid 17 or the water bath 25 The voltage supply 51 of the converter 19 is symbolized by an arrow.

The illustration according to FIG. 3 shows a cover 45 of the compressor unit 1, the cover 45 closing the water bath 25. The diagram shows the power supply 47, the outlet 11, the inlet 9, and ^'as the flow direction in the corresponding apertures 53, 54 for the gaseous Me- dium 3. The rectangular cover 31 has corners 33 of the housing. Since, in particular, the motor can also be produced as a drive unit 7 with a circular outer contour, there is space for the guide system 13 in the corners 33.

The illustration according to FIG. 4 shows a compressor unit 1 with an angular housing 29, the guide system 13 being inside the liquid 17 in the corners of the housing. The FIG. 4 shows a longitudinal section through the compressor unit 1. As already mentioned above, the compressor 5 is followed by the drive unit 7 and then the converter 19. A characteristic of this system is the guide system 13 which has been laid in a space-saving manner and which, for example, has laid pipe coils for cooling the are compressed gaseous medium. The cooling is, for example, a final cooling of the gaseous compressed medium 3 or an intermediate cooling in a multi-stage compressor. The housing 29 can expediently be produced from deep-drawn, rustproof material, such as, for example, stainless steel. The compressor unit 1 is advantageously vibration-damped and / or insulated from other units by dampers integrated in the housing 29. All connections, such as the power supply 47, an interface 49, an inlet 9 and an outlet 11, and openings 53, 54 for the supply and discharge of the gaseous medium 3 are integrated in the cover 45. The interface 49 is used, for example, to control the speed of the converter, which can be made possible by a bus system. Advantageously, the cover 45 is attached to the housing 29 with the aid of a flange, snap or press connection. The seals on the cover 45 to the housing 29 and bushings can be made with rubber or plastic press connections. Depending on the conditions of use of such a compressor unit 1, these can be configured such that the connections on the compressor unit 1 are arranged in a distributed manner.

The compressor unit (1) shown enables an effective cooling effect of the overall system of converter 19, drive unit 7 and compressor 5 to be achieved with a very space-saving design. The enveloping housing 29 results in a low-noise solution for the construction of the compressor unit 1. An optimized vibration damping over wide speed ranges of the drive unit 7 results from the damping via the dampers 43 at several points of the compressor unit 1. Because the connections in the cover 45 are integrated, there is an easy and clear handling of the Connectivity. The compressor unit 1 is also easy to install and fasten in connection with other modules, for example a fuel cell. The compact design of the compressor unit 1 described enables simple removal, particularly in the event of a fault. With a suitable choice of material for the materials used for the compressor unit 1, there is a high degree of maintenance-free operation. If water is used as the liquid 17, rusting of metallic parts can be avoided by using, for example, stainless steel.

The illustration according to FIG. 5 shows a compressor unit 1, in which the converter 19 lies outside the liquid 17. A heat exchanger 35 is located between the drive unit 7 and the converter 19, which can also be referred to as a converter. The liquid 17 is guided through this heat exchanger 35. The heat exchanger 35 is adjacent to both the drive unit 7 and the converter and can thus cool both devices. The converter 19 has a carrier plate 41. On this carrier plate 41 there is at least one power semiconductor component 39 which emits thermal energy to the carrier plate 41. The carrier plate 41 in turn emits the thermal energy to the heat exchanger 35, via which the heat can be released from the system through the liquid 17. As already shown in FIG. 4, the compressor unit has an interface 49. This interface 49 can be used for various signals both for the motor and for the converter. Examples of this are the speed setpoint and actual value, temperature setpoint and actual values and / or other signals which can be transmitted in analog and / or digital form, for example via a BUS system such as CAN bus or Profibus.

The representation according to FIG. 6 shows the three-dimensional representation of a spiral-shaped guide system 13 of the device (15) for influencing the temperature. This design of the guide system 13 also means that voltage as a cooling coil 27, through which the drive unit 7 is wrapped.

The representation according to Figure 7 shows - similarly to figure 6 - a three-dimensional representation of a combination of compressor 5 and drive unit 7, along with ^'a device (15) for influencing the temperature.

The view according to FIG. 8 shows, in perspective, a section of a side view of the compressor unit 1. In the upper half of the figure, the outlet 11 for the gaseous medium 3 is shown, the outlet 11 bordering the guide system 13, which is via the inlet 9 is fed with the gaseous medium 3. The guide system 13 has cooling coils 27 which are in a liquid 17. The liquid 17 is kept in a closed volume by a partial casing 21. The exchange of the liquid 17 takes place via the cooling water inlet 55 and the cooling water outlet 57. The cooling of the motor 7 is also ensured by the exchange of cooling water, ie the liquid 17.

The illustration according to FIG. 9 shows the top view of the connection side of the compressor unit 1. The connection side is designed as a cover 45, which has an inlet for a power supply 47. Furthermore, an interface 49 for connection e.g. a CAN controller. The cooling water enters the cooling water inlet 61 as liquid 17 and flows out of the cooling water outlet 59 out of the system of the compressor unit 1. The air entry is via the inlet 9 and the air outlet is via the outlet 11.

Claims

claims

1. Compressor unit (1) for a gaseous medium (3) which has at least one compressor (5) and a drive unit (7) coupled to it, at least one inlet (9) for the gaseous medium (3) and at least one outlet (11) for the gaseous medium (3) is characterized by a guide system (13) for the gaseous medium (3), which is arranged between an outlet (12) of the compressor (5) and the outlet (11) of the compressor unit (1), and by a device (15) for influencing the temperature, which contains a temperature-influencing medium, the device (15) for influencing the temperature being arranged in direct thermal contact both with the drive unit (7) and with the guide system (13).

2. Compressor unit (1) according to claim 1, d a d u r c h g e k e n n z e i c h n e t that the temperature-influencing medium is air.

3. Compressor unit (1) according to claim 1, so that the temperature-influencing medium is a liquid (17).

4. Compressor unit (1) according to one of claims 1 to 3, so that the gaseous medium (3) can be heated by the temperature-influencing medium (17).

5. Compressor unit (1) according to one of claims 1 to 4, characterized in that the gaseous medium (3) can be cooled by the temperature-influencing medium (17).

6. Compressor unit (1) according to one of the preceding claims, that the drive unit (7) can be cooled by the temperature-influencing medium (17).

7. Compressor unit (1) according to one of the preceding claims, so that the compressor unit (1) has a converter (19) which feeds the drive unit (7).

S. Compressor unit (1) according to one of the preceding claims, so that the converter (19) can be cooled by the temperature-influencing medium (17).

9. Compressor unit (1) according to one of claims 3 to 8, d a d u r c h g e k e n n e z e i c h n e t that the device (15) for influencing temperature at least as one

Partial envelope (21) of the compressor unit (1) is formed, the partial envelope (21) receiving a liquid bath (25) and at least parts of the guide system (13) running in the liquid bath (25).

10. Compressor unit (1) according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the device (15) for influencing temperature cooling coils

(27) as a guide system (13) which run in a spiral around the drive unit (7).

11. Compressor unit (1) according to one of claims 1 to 9, since you rchgek characterized in that the compressor unit (1) has a housing (29) with an angular outer contour (31), the device (15) for influencing the temperature cooling coils (27) as has a guide system (13) which run in corners of the housing (29).

12. Compressor unit (1) according to one of the preceding claims, that the device (15) for influencing the temperature is a heat exchanger (35) by means of which thermal energy of the compressed medium (3) can be delivered to the temperature-influencing medium.

13. Compressor unit (1) according to claim 12, so that the heat exchanger (35) is disc-shaped.

14. Compressor unit (1) according to claim 12 or 13, characterized in that the disk-shaped heat exchanger (35) has a surface (37) and the converter (19) has a power semiconductor component (39) on a carrier plate (41), the Carrier plate (41) with the surface (37) of the heat exchanger (35) is thermally connected.

15. Compressor unit (1) according to one of the preceding claims, so that the compressor (5) is a side-channel compressor.

16. Nerdichtereinheit (1) according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the compressor (5) has at least two compressors.

17. Compressor unit (1) according to one of the preceding claims, so that the drive unit (7) is an electric motor.