JP2007038950A - Air conditioning system for vehicles equipped with fuel cells - Google Patents

Abstract

An object of the present invention is to realize an air conditioner for a vehicle equipped with a fuel cell that uses waste heat from equipment necessary for the system and does not provide a new heat source.
Therefore, in a vehicle air conditioner equipped with a fuel cell including a heating unit, a compressor, and a cooler having a cooling function unit and a heating function unit, the cooling water passage is provided with cooling water for the fuel cell. A communication passage connecting the discharge side and the cooler, and three parallel passages in the middle of the passage connecting the cooler and the cooling water pump, the three passages being a first passage connected to the heating means, and a cooling water The second passage connected to the cooling radiator and the third passage bypassing the second passage are provided with an opening / closing valve on the cooler side of the heating means of the first passage, and the cooling water is supplied to the second passage. And a switching valve that flows only in one of the third passages, the open / close valve is opened when the cooling water temperature is higher than the first set value and heating is used, and the switching valve is switched according to the cooling water temperature value in the heating usage state It is done.
[Selection] Figure 1

Description

  The present invention relates to an air conditioner for a vehicle equipped with a fuel cell, and in particular, an air conditioner for a vehicle equipped with a fuel cell that uses waste heat from equipment necessary for a system equipped with a fuel cell and does not provide a new heat source. It relates to the device.

  A fuel cell mounted on a vehicle, for example, a solid polymer electrolyte membrane fuel cell, generates electricity by an electrochemical reaction using a fuel gas mainly containing hydrogen and an oxidant gas containing oxygen. As a result of the electrochemical reaction, water is the only substance that is discharged, and has attracted attention as a clean power generator.

Japanese Patent No. 3141606 Japanese Patent Laid-Open No. 2004-243829 JP 2003-118396 A

  By the way, in a vehicle air conditioner equipped with a conventional fuel cell, usually, in a four-wheeled vehicle, waste heat from an internal combustion engine is used as a heat source for winter heating and defrost.

  However, in a vehicle equipped with a fuel cell, the waste heat temperature is lower than that of the internal combustion engine (about 60 degrees ± 10 degrees), and it becomes insufficient as a heat source.

  In the case of a pure hydrogen type that does not have a reforming system or the like, the tendency is particularly remarkable.

  As a solution to such a problem, there is a method of adding an auxiliary heat source. For example, in the above-mentioned Patent Document 1, burner heating is used.

  However, when a new heat source is added in this way, there is an inconvenience that the vehicle efficiency during heating is lowered and the fuel consumption is lowered.

  Moreover, in the above-mentioned patent document 2, it utilizes for the dehumidification of an air conditioning.

  Furthermore, in above-mentioned patent document 3, utilizing as a heat source is also considered.

  However, in such a case, there is an inconvenience that it is necessary to prepare a special part in which the cooling radiator and the compressed air cooling cooler are integrated.

  An object of the present invention is to realize a vehicle air conditioner equipped with a fuel cell that uses waste heat from equipment necessary for a system equipped with a fuel cell and does not provide a new heat source.

  Therefore, in order to eliminate the above disadvantages, the present invention provides heating means using heat discharged from a cooling water passage for cooling the fuel cell as a heat source, and a compressor for compressing air supplied to the fuel cell. And a cooler having a cooling function part for cooling the air compressed by the compressor and a heating function part for heating the cooling water in the cooling water passage by heat discharged when the air is cooled. In a vehicle air conditioner equipped with a fuel cell, the cooling water passage includes a communication passage connecting the cooling water discharge side of the fuel cell and the cooler, and a passage connecting the cooler and the cooling water pump. The three passages include a first passage connected to the heating means, a second passage connected to the cooling water cooling radiator, and a third passage bypassing the second passage. Through And an on-off valve is provided on the cooler side of the heating means of the first passage, and the cooling water is switched so as to flow only to one of the second passage and the third passage. A switching valve is provided, and the on-off valve has a cooling water temperature higher than the first set value and is opened when heating is used, and the switching valve is switched in a heating use state and according to the value of the cooling water temperature. It is characterized by.

  As described above in detail, according to the present invention, heating means using heat discharged from the cooling water passage for cooling the fuel cell as a heat source, a compressor for compressing air supplied to the fuel cell, and a compressor Equipped with a fuel cell comprising a cooling function part for cooling the air compressed in the air and a cooler having a heating function part for heating the cooling water in the cooling water passage by the heat discharged when cooling the air In the vehicle air conditioner, the cooling water passage includes a communication passage connecting the cooling water discharge side of the fuel cell and the cooler, and three parallel passages in the middle of the passage connecting the cooler and the cooling water pump. The three passages include a first passage connected to the heating means, a second passage connected to the cooling water cooling radiator, and a third passage bypassing the second passage, Passage heating means An on-off valve is provided on the side of the cooler, a switching valve is provided to switch the cooling water so that it flows only to one of the second passage and the third passage. Higher than the value and opened when heating is used, and the switching valve is switched according to the cooling water temperature value by switching according to the cooling water temperature value in the heating usage state. Therefore, it is possible to properly distribute the heat source that has been waste heat from the cooler to the heating heat source and the function to warm up the fuel cell, and use the waste heat from the equipment required for the system equipped with the fuel cell Therefore, it is not necessary to provide a new heat source, which can simplify the system and increase the efficiency from the viewpoint of energy consumption.

  By inventing as described above, the on-off valve is opened when the cooling water temperature is higher than the first set value and heating is used, and the switching valve is switched according to the value of the cooling water temperature in the heating use state. Valve switching is controlled according to the value of the water temperature, and the heat source that is waste heat from the cooler is properly assigned to the heating heat source and the function to warm up the fuel cell, and the equipment required for the system equipped with the fuel cell Since the waste heat from is used, it is not necessary to provide a new heat source, thereby improving the efficiency from the viewpoint of simplification of the system and energy consumption.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  1 to 3 show an embodiment of the present invention. In FIG. 2, 2 is an air conditioner for a vehicle equipped with a fuel cell, and 4 is a fuel cell.

  As shown in FIG. 2, the air conditioner 2 compresses air supplied to the fuel cell 4 and heating means 8 using heat discharged from a cooling water passage 6 for cooling the fuel cell 4 as a heat source. Cooling having a compressor 10, a cooling function part that cools the air compressed by the compressor 10, and a heating function part that heats the cooling water in the cooling water passage 6 using heat discharged when the air is cooled. And a container 12.

  The heating means 8 includes a heater core 14 and a blower 16 that blows air to the heater core 14.

  Further, as shown in FIG. 2, an air introduction passage 18 for introducing air is connected to the upstream side of the compressor 10 and the compressed compressed air is supplied to the fuel cell 4 on the downstream side of the compressor 10. A compressed air introduction passage 20 to be introduced is connected and provided.

  In other words, in a vehicle equipped with the fuel cell 4, compressed air is supplied to improve the output density of the fuel cell 4, but because of the adiabatic compression by the compressor 10, the temperature becomes 180 degrees or more immediately after compression, When the fuel cell 4 is supplied, it is necessary to cool the compressed air compressed by the compressor 10 to an appropriate temperature, for example, 60 degrees ± 10 degrees.

  In order to cope with this, the cooler 12 is disposed immediately downstream of the compressor 10. The cooler 12 includes a cooling function unit that cools the air compressed by the compressor 10 and a heating function unit that heats the cooling water in the cooling water passage 6 using heat discharged when the air is cooled. It functions as a heat exchanger.

  Further, the cooling water passage 6 includes three communication passages 22 connecting the cooling water discharge side of the fuel cell 4 and the cooler 12, and three passages connecting the cooler 12 and the cooling water pump 24. The parallel passage 26, which is a three passage, includes a first passage 28 that is connected to the heating means 8, a second passage 32 that is connected to the cooling water cooling radiator 30, and the second passage 32. And a third passage 34 that bypasses the passage 32 of the first passage 28. An opening / closing valve 36 is provided on the cooler 12 side of the heating means 8 of the first passage 28, and cooling water is supplied to the second passage 32 and the third passage 34. A switching valve 38 for switching so as to flow only to one of the third passages 34 is provided, and the on-off valve 36 is opened when the cooling water temperature is higher than the first set value and heating is used, and the switching is performed. When the valve 38 is in a heating use state, A configuration that is switched according to the value of the coolant temperature.

  More specifically, the cooling water passage 6 includes three parallel passages connecting the cooling water discharge side of the fuel cell 4 and the cooling device 12, and connecting the cooling device 12 and the cooling water pump 24. The first to third passages 28, 32 and 34, which are the passage 26, and the supply passage 40 that connects the cooling pump 24 and the coolant supply side of the fuel cell 4.

  A water temperature sensor 42 is provided in the middle of the supply passage 40. Reference numeral 44 denotes a radiator blower provided in the cooling water cooling radiator 30.

  The on-off valve 36 is opened when the cooling water temperature TW is higher than a first set value, for example, the first threshold value Tth1, and heating is used.

  The switching valve 38 connects the b port and the c port to enable the second passage 32, and connects the a port and the b port to bypass the second passage 32. It comprises a three-way valve having ports a through c that allow the passage 34 to be used.

  At this time, the switching valve 38 switches between the b port and the c port according to the value of the cooling water temperature TW, that is, when the cooling water temperature TW is higher than the second threshold value Tth2, which is a set value. The second passage 32 can be connected and used, and the cooler 12 and the second passage 32 are switched to communicate with each other.

  Further, when the coolant temperature TW is lower than the second threshold value Tth2, the switching valve 38 can use the third passage 34 that connects the a port and the b port and bypasses the second passage 32. Are switched as follows.

  The first threshold value Tth1 that is the first set value and the second threshold value Tth2 that is the set value are given hysteresis characteristics as shown in FIG. Thus, by providing the hysteresis characteristic, frequent switching of the operation is prevented.

  In other words, when the temperature drops due to this hysteresis characteristic, when the cooling water temperature TW becomes equal to or lower than the second threshold value Tth2 in the state of (3) in FIG. 3, the cooling system is switched to the state of (2) in FIG. When the cooling water temperature TW becomes equal to or lower than the first threshold value Tth1 during any operation, the on-off valve 36 is closed and the switching valve 38 is switched to connect the a port and b port to the second port. A third passage 34 that bypasses the passage 32 can be used to minimize heat dissipation from the cooling system.

  Here, if the flow of the cooling water in the cooling water passage 6 is additionally described, the cooling water discharged from the fuel cell 4 reaches the cooler 12 through the communication passage 22 as shown in FIG.

  In this cooler 12, the air compressed by the compressor 10 is cooled by the cooling function unit, and the cooling water in the cooling water passage 6 is heated by the heat discharged when the air is cooled by the heating function unit. The so-called heat exchange is performed, and the heated cooling water reaches the first to third passages 28, 32, 34 which are the parallel passages 26.

  When the on-off valve 36 disposed in the middle of the first passage 28 is in an open state, the cooling water flows in the first passage 28. At this time, the cooling water passes through the heater core 14 constituting the heating means 8 and reaches the cooling water pump 24.

  Further, if the second port 32 can be used by connecting the b port and the c port by the switching valve 38, the cooling water flows in the second passage 32. At this time, the cooling water passes through the cooling water cooling radiator 30 and reaches the cooling water pump 24.

  Further, when the switching valve 38 enables the use of the third passage 34 that connects the a port and the b port and bypasses the second passage 32, the third passage 34 is used instead of the second passage 32. Cooling water will flow inside. At this time, the cooling water reaches the cooling water pump 24 directly.

  Then, the coolant that has reached the coolant pump 24 reaches the supply passage 40 and is supplied to the fuel cell 4 through the water temperature sensor 42.

  Next, the operation will be described along the control flowchart of the air conditioner for the vehicle equipped with the fuel cell of FIG.

  When the control program is started and the system is started (102), the first threshold value Tth1 is set to 55 degrees, the second threshold value Tth2 is set to 60 degrees (104), and the on-off valve 36 is closed. At the same time, the switching valve 38 formed of a three-way valve is connected to the a port and the b port so that the third passage 34 that bypasses the second passage 32 can be used (106).

  Then, the process proceeds to a determination (108) as to whether or not the coolant temperature TW is equal to or higher than the first threshold Tth1, and when the determination (108) is NO, the first threshold Tth1 is set to 55 degrees (110). Then, the process proceeds to determination (132) of whether or not a failure has occurred, which will be described later. If determination (108) is YES, the first threshold value Tth1 is set to 50 degrees (112) and whether there is a heating request, That is, the process proceeds to the determination (114) of whether or not heating is being used.

  In the determination (114) of whether or not there is a heating request, that is, whether or not heating is being used, if the heating is not used, the on-off valve 36 is closed and the switching is performed. The valve 38 is switched to connect the b-port and the c-port so that the second passage 32 can be used (116). When the heater is turned on, the cooling water temperature TW is set to the second threshold value. The process proceeds to determination (118) of whether or not Tth2 or more.

  After the process (116) in which the on-off valve 36 is closed and the switching valve 38 is switched to connect the b-port and the c-port so that the second passage 32 can be used. The cooling water temperature TW is raised to 65 degrees by adjusting the amount of water and the air flow of the radiator blower 44 as a fan, and this cooling water temperature TW is maintained (120). Transition.

  Further, in the determination (118) of whether or not the coolant temperature TW is equal to or higher than the second threshold Tth2, if the determination (118) is NO, the second threshold Tth2 is set to 60 degrees (122), and the determination is made. If (118) is YES, the second threshold Tth2 is set to 55 degrees (124).

  Then, after the process (122) for setting the second threshold Tth2 to 60 degrees, the on-off valve 36 is opened, and the switching valve 38 is switched to connect the a port and the b port. The third passage 34 that bypasses the passage 32 is made available (126), and the process proceeds to the determination (132) of whether or not a failure occurs, which will be described later.

  Further, after the processing (124) for setting the second threshold value Tth2 to 55 degrees, the on-off valve 36 is opened, and the switching valve 38 is switched to connect the b port and the c port. The passage 32 can be used (128), and the cooling water temperature TW is increased to 65 degrees by adjusting the pump water supply amount and the air volume of the radiator blower 44, which is a fan, and the cooling water temperature TW is maintained (120). Then, the process proceeds to the determination (132) of whether or not a failure has occurred.

  In the determination (132) of whether or not a failure has occurred, if the determination (132) is YES, a fail process (134) is performed, and the system shifts to a system stop (140) for terminating a control program described later. If the determination (132) is NO, the process proceeds to determination (136) as to whether or not the vehicle is stopped.

  In the determination (136) of whether or not the vehicle is in a stopped state, if the determination (136) is NO, the process proceeds to the determination (138) of whether or not the second threshold Tth2 is 55 degrees or more. If the determination (136) is YES, the process proceeds to a system stop (140) for terminating a control program described later.

  In the determination (138) of whether or not the second threshold Tth2 is 55 degrees or more, if the determination (138) is YES, the on-off valve 36 is closed and the switching valve 38 formed of a three-way valve is used. Is returned to the processing (106) in which the third passage 34 for connecting the a port and the b port to bypass the second passage 32 is usable, and if the determination (138) is NO, the cooling is performed. The process returns to the determination (108) of whether or not the water temperature TW is equal to or higher than the first threshold value Tth1.

  As a result, the cooling water passage 6 is arranged in the middle of the passage 22 connecting the cooling water discharge side of the fuel cell 4 and the cooler 12 and the passage connecting the cooler 12 and the cooling water pump 24. The parallel passage 26, which is three passages, includes a first passage 28 connected to the heating means 8, a second passage 32 connected to the cooling water cooling radiator 30, and the second passage 32. And a third passage 34 that bypasses the second passage 32, an on-off valve 36 is provided on the cooler 12 side of the heating means 8 of the first passage 28, and the cooling water is connected to the second passage 32. A switching valve 38 for switching so as to flow only to one of the third passages 34 is provided, and the on-off valve 36 is opened when the cooling water temperature is higher than the first set value and heating is used. The switching valve 38 is in a heating use state. In addition, since the switching of the valve is controlled according to the value of the cooling water temperature by switching according to the value of the cooling water temperature, the heat source waste heat from the cooler 12 is used as a heating heat source and the fuel cell 4 is heated. Since the waste heat from the equipment necessary for the system equipped with the fuel cell 4 is used, it is not necessary to provide a new heat source. It is possible to improve efficiency from the viewpoint of simplification and energy consumption.

  Further, when the cooling water temperature TW is higher than the second threshold value Tth2, which is a set value, the switching valve 38 connects the b port and the c port and enables the use of the second passage 32. By switching so as to communicate with the second passage 32, even if the cooling water is used for heating, when the cooling water temperature is high, it is possible to control the heat radiation amount only by switching the passage.

  The present invention is not limited to the above-described embodiments, and various application modifications are possible.

  For example, in the embodiment of the present invention, a simple switching type three-way valve is used as the switching valve, but an adjustment type valve can be used instead of the three-way valve. is there.

  Then, the temperature adjustment of the cooling water can be controlled more finely by the adjustment type valve.

It is a flowchart for control of the air conditioner of the vehicle carrying the fuel cell which shows the Example of this invention. It is a figure which shows a hysteresis characteristic. 1 is a system configuration diagram of a vehicle air conditioner equipped with a fuel cell.

Explanation of symbols

2 Vehicle air conditioners equipped with fuel cells,
4 Fuel Cell 6 Cooling Water Passage 8 Heating Means 10 Compressor 12 Cooler 14 Heater Core 16 Blower 18 Air Introduction Passage 20 Compressed Air Introduction Passage 22 Communication Passage 24 Cooling Water Pump 26 Parallel Passage 28 First Passage 30 Cooling Water Cooling Radiator 32 Second passage 34 Third passage 36 On-off valve 38 Switching valve 40 Supply passage 42 Water temperature sensor 44 Radiator blower

Claims (2)

  Heating means using heat discharged from a cooling water passage for cooling the fuel cell as a heat source, a compressor for compressing air supplied to the fuel cell, and a cooling function unit for cooling the air compressed by the compressor And an air conditioner for a vehicle equipped with a fuel cell comprising: a cooler having a heating function unit that heats the cooling water in the cooling water passage by heat discharged when cooling air; The passage includes a communication passage that connects the cooling water discharge side of the fuel cell and the cooler, and three parallel passages in the middle of the passage that connects the cooler and the cooling water pump. The first passage connected to the heating means, the second passage connected to the cooling water cooling radiator, and the third passage bypassing the second passage, the heating of the first passage Colder than means An on-off valve is provided on the vessel side, and a switching valve is provided for switching so that the cooling water flows only to one of the second passage and the third passage. The on-off valve has a cooling water temperature of the first temperature. An air conditioner for a vehicle equipped with a fuel cell, wherein the air conditioner is higher than a set value and is opened when heating is used, and the switching valve is switched according to a cooling water temperature value in a heating use state.   2. The vehicle equipped with the fuel cell according to claim 1, wherein the switching valve is switched so that the cooler communicates with the second passage when the value of the coolant temperature is higher than a set value. Air conditioner.

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