WO2008037242A1

WO2008037242A1 - Air-conditioning system for standstill air-conditioning of a motor vehicle

Info

Publication number: WO2008037242A1
Application number: PCT/DE2007/001488
Authority: WO
Inventors: Manfred Pfalzgraf; Markus Bedenbecker; Matthias Boltze; Andreas Engl
Original assignee: Enerday Gmbh
Priority date: 2006-09-27
Filing date: 2007-08-22
Publication date: 2008-04-03
Also published as: DE102006045672A1

Abstract

The invention relates to an air-conditioning system (112) for standstill air-conditioning of a motor vehicle (110), having a fuel cell. Here, it is advantageously provided that the air-conditioning system (112) is designed to be arranged in a vehicle interior space (178) which is to be cooled. The invention also relates to a motor vehicle having an air-conditioning system of said type.

Description

Air conditioner for stationary air conditioning of a motor vehicle

The invention relates to an air conditioner for stationary air conditioning of a motor vehicle, with a fuel cell.

Furthermore, the invention relates to a motor vehicle with such an air conditioner.

From DE 102 23 949 Al an air conditioning system with a fuel cell for stationary air conditioning of a vehicle is known. However, retrofitting such air conditioning systems is often expensive.

The object of the present invention is the generic air conditioning in such a way that a simple retrofitting is guaranteed.

This object is solved by the features of claim 1.

Advantageous embodiments and modifications of the invention will become apparent from the dependent claims.

The air conditioning system according to the invention builds on the generic state of the art in that the air conditioning system is designed to be arranged in a vehicle interior to be cooled. This further development has the advantage that it is possible to dispense with the laying of air ducts in the motor vehicle and thus to realize a very simple retrofitting. - -

In addition, it may be advantageously provided that the air conditioning system is designed as a cooling tower with an independent cooling circuit. This independent functionality supports simple retrofitting.

Furthermore, it can be provided that the air conditioning system has a refrigerator. As a result, the functionality of the air conditioning system can be extended.

This embodiment can be developed in such a way that an evaporator associated with the refrigerator can be switched parallel to an evaporator for cooling the vehicle interior. As a result, the operation for cooling the vehicle interior is independent of the cooling of the refrigerator, which preferably takes place in continuous operation.

With the motor vehicle according to the invention, which has such an air conditioner, the advantages mentioned above can be achieved in a metaphorical manner.

Preferred embodiments of the invention will now be described by way of example with reference to the accompanying drawings.

Show it:

Figure 1 is a schematic representation of an air conditioner according to the invention;

Figure 2 is a schematic representation of a motor vehicle in which the air conditioner according to the invention is mounted; and

FIG. 3 is a flow chart of an air conditioning operation. Figure 1 shows a schematic representation of an air conditioner according to the invention. The air conditioning system 112 installed in a motor vehicle 110 (installation position, see FIG. 2) comprises as main elements a fuel cell system 14 and a refrigeration circuit 116. The air conditioning system 112 has the external appearance of an air conditioning tower 192 whose internal structure is outlined by the dashed line 194. The air conditioning tower 192 has an air outlet 196 and an air inlet 198. Further, a refrigerator 200 is disposed in the air conditioning tower 192.

The fuel cell system 14 comprises a reformer 18, to which fuel can be fed via a fuel train 20 from a fuel tank (not shown). Further, the reformer 18 at a second Brennstoffzuführstufe by means of a fuel strand 22 also from the fuel tank fuel can be supplied. Suitable fuel types are diesel, gasoline, natural gas and other types of fuel known from the prior art. Furthermore, that is

Reformer 18 via an oxidant strand 24 Oxidati- onsmittel, ie in particular air, can be fed. The reformate produced by the reformer 18 can be fed to a fuel cell stack 26. Alternatively, instead of the fuel cell stack 26, only one fuel cell may be provided. The reformate is a hydrogen-containing gas which is converted in the fuel cell stack 26 by means of cathode feeds conveyed via a cathode feed line 28 with generation of electrical energy and heat. The generated electrical energy can be fed via an electrical line 30 to an electric motor 32, a battery 34 and an electrical heating device 36 of the air conditioning system 112. This can be done directly or by feeding the energy over one central node in the electrical system of the motor vehicle 110. In the illustrated case, the anode exhaust gas via an anode exhaust line 38 of a mixing unit 40 of an afterburner 42 can be fed. Furthermore, fuel can be supplied to the afterburner 42 via a fuel line 44 from the fuel tank and via an oxidant strand 46 to oxidizing agent. In the fuel strands 20, 22 and 44 are suitable, not shown conveyors, such as pumps, arranged. Likewise, in the oxidant strands 24 and 46 corresponding, not shown conveyors, in this case, preferably blower arranged. These conveyors can be powered directly from the fuel cell stack 26 or from the battery 34. In the afterburner 42, a conversion of the depleted anode exhaust gas with the pumped fuel and oxidizing agent to a combustion exhaust gas, which is mixed in a mixing unit 48 with cathode exhaust air, which is conveyed via a Kathodenabuftstrang 50 from the fuel cell stack 26 to the mixing unit 48. The combustion exhaust gas, which almost no

Contains pollutants, flows through a heat exchanger 52 for preheating the cathode feed air and finally leaves the fuel cell system 14 via an exhaust gas outlet 54th

In the refrigerant circuit 116, a compressor 56, a condenser 58, an expansion element 60, an evaporator 62, and a refrigerator evaporator 202 connected in parallel to the evaporator 62 are arranged. The refrigerator evaporator 202 is disposed in the refrigerator 200. At the branches to the refrigerator evaporator 202, adjusting devices 204 are placed, with which either the evaporator 62, the refrigerator evaporator 202 or both can be integrated into the refrigeration circuit 116. The compressor 56 can be driven by the electric motor 32, which in turn preferably is supplied with energy by the fuel system cell stack 26 of the fuel cell system 14, but can also be supplied with energy from the battery 34 for a short time. The evaporator 62 is associated with a blower 64. Ambient air can be drawn in from the outside via an outside air line 66. The term "from the outside", as used in connection with this invention, in this case means from outside the interior 178, thus designates the surrounding the motor vehicle 110 air. The outside air duct 66 leads to an adjusting device 168, which can supply the outside air to the blower 64. The air directed from the actuator 168 to the fan 64 flows past the evaporator 62 as airflow 70. In this way, heat energy can be withdrawn from the air stream 70 by the evaporator 62. The cooled air flow can then be supplied via an adjusting device 72, an air guide 74 and the air outlet 196 to a vehicle interior 178. The adjusting device 72 can be realized, for example, by a solenoid valve or by check valves, which in each case allow only one flow from the two supply lines to the air guide 74. From the vehicle interior 178, the air flows via the air inlet 198 and an air guide 82 back to the adjusting device 168, where it is completely or partially discharged to the outside or back to the bubble 64 is passed. For the guidance of the air to the outside, a corresponding line is provided, which is not shown for reasons of clarity. The circuit of the adjusting device 168 can thus be realized either a fresh air or a recirculation concept in which air is sucked from the outside via the outside air duct 66 or the air is recirculated from the air duct 82. Mixed forms of these modes are possible. Furthermore, the condenser 58 is associated with a blower 206, with which an air flow 208 from a control unit tion 168 to an air guide 184 or opposite thereto can be generated. By means of the adjusting device 168 can be supplied via the outside air line 66 to the blower 206 air. The air flow 208 is conducted past the condenser 58, where heat energy is supplied to it, if the refrigeration circuit 116 is in operation. The thus preheated air flow is supplied to the air guide 184, which ends at an actuator 210. At the adjusting device 210, the preheated air flow can optionally additionally be acted upon by a fan 212 with waste heat from the hot parts of the fuel cell system 14. For this purpose, air sucked in by the blower 212 flows directly past hot parts of the fuel cell system 14 or through heat exchangers (not shown) which mediate between the intake air stream and the hot parts. The hot parts of the fuel cell system 14 are preferably the reformer 18, the fuel cell stack 26 and the afterburner 42. In this way, by the waste heat of the hot parts of the fuel cell system 14 heat energy can be supplied to the air flow. This warm air flow is forwarded in an air duct 190, which is provided with the electric heater 36. The electrical heater 36 is powered directly by an energy generated by the fuel cell stack 26 or stored by the battery 34 to further heat the airflow. This air continues to flow to the actuator 72 and thence to the air outlet 196. After passing through the interior 178, the airflow back to the actuator 168 via the air inlet 198 and the air duct 82 where it is either discharged to the outside or returned to the blower 206 , Here, too, can be on the circuit of the adjusting device 168 thus realize either in such a heating operation, a recirculation concept, in the air from the outside is sucked in via the outside air line 66 or the air from the air duct 82 is recirculated.

FIG. 2 shows a schematic illustration of a motor vehicle 110 in which the air conditioning system 112 according to the invention is mounted. The motor vehicle 110 is preferably a stretch limousine, in which the air conditioning system 112 is arranged in the form of a tower, preferably as a retrofittable unit. In addition to the described air conditioning system 112, the motor vehicle 110 has a conventional air conditioning system 92, in which a compressor of a conventional refrigeration circuit is mechanically drivable by a drive unit 94, preferably an internal combustion engine. During the journey of the motor vehicle 110 and the associated operation of the drive unit 94, the interior 178 can be cooled via the conventional on-board air conditioning system 92 in a generally known manner or heated by means of waste heat from the drive unit 94. When the drive unit 94 is at a standstill, the interior space 178 can be conditioned via the air conditioning system 112 according to the invention.

Below, various operating conditions are shown, which can be realized by means of the air conditioner 112; In this case, optionally or alternatively, the refrigerator evaporator 202 can be integrated into the refrigeration circuit 116 by means of the adjusting devices 204 in all operating states, so that, for example, drinks in the refrigerator can be cooled:

Cooling operation with circulating air circulation: In this operating state, the adjusting device 168 is switched so that air is guided from the interior 178 via the air inlet 198, the air guide 82 to the blower 64. This air flow 70 is cooled and discharged via the adjusting device 72, the air guide 74 and the air outlet 196 into the interior 178, whereby it is cooled. In order to avoid heating of the interior 178 during cooling operation, the waste heat of the fuel cell system 14 is guided by the blower 212 to the adjusting device 210. The actuator 210 directs the waste heat through the air duct 184 to the blower 206, which is operated so that the air from the air duct 184 is passed directly over the capacitor 58 to the adjusting device 168, whereby the waste heat of the capacitor 58 transmitted to the air becomes. This

Waste air flow is discharged from the actuator 168 to the outside. Alternatively, corresponding (not shown) additional fans and lines may be provided which dissipate the waste heat of the fuel cell system 14 and the waste heat of the capacitor 58 to the outside.

Cooling operation with external air supply: In this operating state, the adjusting device 168 is switched such that outside air is guided via the outside air line 66 to the blower 64. The air flow 70 is cooled and over the

Adjustment device 72, the air guide 74 and the air outlet 196 guided in the interior 178. The over the air guide 82 from the interior 178 leading air flow is discharged from the actuator 168 to the outside. With regard to the removal of the waste heat of the fuel cell system 14 and the capacitor 58, the measures explained in the context of the cooling operation described above are taken.

Heating mode with circulating air circulation: In this operating state, an air flow 208 is led to the blower 206 via the air inlet 198, the air duct 82 and the adjusting device 168. If the refrigerator 200 is to be cooled, the refrigeration circuit 116 is in operation such that the actuators 204 only the refrigerator evaporator 202 in the Integrate cooling circuit 116. By this operation of the refrigerant circuit 116, waste heat is released at the condenser 58. With this waste heat, the air flow 208 is preheated. The preheated air stream flows via the air guide 184 to the adjusting device 210, where the air flow can additionally be supplied with waste heat from the hot parts of the fuel cell system 14 via the blower 212. If the refrigerator evaporator 202 is not in operation, then here the air flow is heated for the first time. The preheated in this way air is guided by the air guide 190 to the electric heater 36 and on to the adjusting device 72. The electric heater 36 is operated to heat the air in the air guide 190 with e- lectric power. Subsequently, the heated air flows via the adjusting device 72, the air guide 74 and the air outlet 196 into the interior 178.

Heating mode with outside air supply: In this operating state, outside air is supplied via the outside air line 66 from the adjusting device 168 to the blower 206. If the condenser 58 generates waste heat by the cooling of the refrigerator 200, as described above, it preheats the air flow. This air flow, as in the operating state described above, via the Luftführung 184, the adjusting device 210 with the associated heating, the air guide 190, the electric heater 36, the actuator 72, the air guide 74 and the air outlet 196 in the interior 178th directed. Subsequently, the air is guided via the air guide 82 to the adjusting device 168, where it is discharged to the outside.

These different operating states are controlled by an electronic control unit which, depending on the temperature in the interior 178, outside temperature set Set temperatures and desired air conditioning operation selects the appropriate operating condition. This electronic control unit is not shown in the figures for reasons of clarity, but it is immediately apparent to those skilled in the art that these at least with the corresponding conveyors in the strands 20, 22, 24, 44 and 46 of the power distribution in the electrical line 30, the blowers 64, 206 and 212, the electric heater 36, the electric motor 32, the adjusting means 72, 168 and 204 and the corresponding temperature sensors is connected.

Alternatively, the air flow into or out of the vehicle interior 178 may be reversed, i. the air can be blown laterally on the air conditioning tower 192 and sucked up.

FIG. 3 shows a flowchart of the air conditioning operation of the air conditioner 112 according to the present invention. The routine of FIG. 3 executed by the electronic control unit starts in step S100 when the air conditioner 112 is turned on manually. At step SIOL, it is determined whether the power plant 94 is still operating. The process does not proceed to step S102 until the query in step S101 is negative. In step S102, it is determined whether the user has selected an automatic standby mode via a selection switch or a corresponding programming of the air conditioner 112. If not, the process proceeds to step S103, where it is determined whether the user manually selects

Standby air conditioning has selected. If this is not the case, then the process proceeds to step S104, where it is determined whether the user has manually selected comfort climate control. If this is answered with "YES" is th, the process proceeds to step S105 where comfort air-conditioning is performed. In this comfort air-conditioning, the interior 178 of the motor vehicle 110 is air-conditioned to a comfort temperature (eg 18 ° C.) by making a selection from the various heating and cooling modes from the electronic control unit. The subsequent step S106 determines that this feel-good air conditioning is automatically stopped when the power plant 94 is started. Accordingly, if it is determined in step S106 that the power plant 94 is not running yet, it is determined in S107 whether the air conditioner 112 has been turned off manually. For a manual shutdown, the process ends at step S112, otherwise the process returns to step S105. If the user has not selected feel-good conditioning in step S104, the process returns to step S110. If it has been determined in step S102 that an automatic standby air conditioning has been selected, then the process proceeds to step S08, where it is determined whether a comfortable air conditioning has been manually selected by the user. If so, then the process proceeds to step S105, where the well-being conditioning described above is performed. If it is determined in step S108 that the user has not selected feel-good air-conditioning, then the process proceeds to step S109 where the standby air conditioning according to the present invention is performed. In this standby air conditioning, the temperature in the interior 178 is regulated to a setpoint setpoint temperature (eg 25 ° C.), which differs from the comfort temperature. This is realized by suitably selecting the electronic control unit from the described heating and cooling modes. If the outside temperature is high, then the ready set temperature is greater than the comfort temperature. Is low against the outside temperature, then the ready set temperature is lower than the comfort temperature. Thus, for example, at high outside temperature, a heating of the interior 178 is prevented and, if necessary, ensures a very fast reaching the comfort temperature, because the interior 178 is already "pre-cooled". After step S109, the process proceeds to step S110, where it is checked if the power plant 94 has been started. If so, then the process returns to step S100. Otherwise, the process proceeds to step S11, where it is determined whether the user has manually turned off the air conditioning - if "YES", then the process ends in step S112 and if "NO", then the process returns to step S108.

The preferred operation of the air conditioner 112 in practice is to select automatic standby air conditioning. If the drive unit 94 is operated, then the interior 178 can be conditioned via the vehicle optimized, very effective and specially designed air conditioning 92. As soon as the drive unit 94 is switched off (and the occupants leave the motor vehicle 110 by mistake), the air conditioning system 112 starts the standby air conditioning, which cools the interior space at high outside temperature to, for example, 25 ° C. This standby air conditioning operation can be carried out with 12 liters of fuel without any problems for 12 days in continuous operation. The standby air conditioning operation is performed until the user selects a Wohlfühlklima- tisierung shortly before driving, which then cools the interior 178 to, for example 18 ⁰ C. The Wohlfühlklimatisierung is then carried out until the drive unit 94 is restarted. Although it has been described above that the air conditioner 112 is operated only when stationary, ie, when the power plant 94 is at a standstill, this is only the preferred mode of operation and it is also possible to operate the air conditioner 112 during operation of the power plant 94.

The features of the invention disclosed in the foregoing description, in the drawings and in the claims may be essential to the realization of the invention both individually and in any combination.

List of reference numbers:

14 fuel line system

18 reformers 20 fuel strands

22 fuel strands

24 oxidizer strand

26 fuel cell stack

28 cathode inlet air line 30 Electrical line

32 electric motor

34 battery

36 Electric heater

38 anode exhaust line 40 mixing unit

42 afterburner

44 fuel strands

46 Oxidizing agent strand

48 mixing unit 50 cathode exhaust line

52 heat exchangers

54 exhaust outlet

56 compressor

58 condenser 60 expansion element

62 evaporator

64 blowers

66 outside air line

70 air flow 72 adjusting device

74 air duct

82 air duct

92 Conventional air conditioning

94 drive unit 110 motor vehicle

112 air conditioning

116 refrigerant circuit

168 Control device 178 Interior

184 air duct

190 air duct

192 Air conditioning tower

194 Interior of the air conditioner 196 Air outlet

198 air intake

200 fridge

202 refrigerator evaporator

204 actuators 206 blower

208 airflow

210 adjusting device

212 blowers

Claims

An air conditioning system (112) for stationary air conditioning of a motor vehicle (110), comprising a fuel cell (26), characterized in that the air conditioning system (112) is designed to be arranged in a vehicle interior (178) to be cooled.

2. Air conditioning system (112) according to claim 1, characterized in that the air conditioning system (178) is designed as a cooling tower with independent cooling circuit.

3. Air conditioning system (112) according to one of the preceding claims, characterized in that the air conditioning system (112) has a refrigerator (200).

4. The air conditioner (112) according to claim 3, characterized in that a refrigerator (200) associated evaporator (202) parallel to an evaporator (62) for cooling the vehicle interior (178) is switchable.

5. motor vehicle (110) with an air conditioner (112) according to one of claims 1 to 4.