JP2010089568A - Vehicle compartment air-conditioning/fuel cell cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle compartment air-conditioning/fuel cell cooling device for obtaining a high cooling effect of cooling water of a fuel cell even when a radiator for exchanging heat between outside air and the cooling water for cooling the fuel cell is arranged on the leeward side of an outdoor device for an air-conditioning function with respect to the flow of the outside air. <P>SOLUTION: During cooling operation, an air-conditioning coolant whose temperature is raised by a compressor 11 is moved into a water/coolant heat exchanger 13 before achieving to the outdoor device 16, and an FC cooling water (fuel cell cooling water) which has cooled the fuel cell 2 is moved into the water/coolant heat exchanger 13 before achieving to the radiator 42. After that, heat is transferred from the air-conditioning coolant to the FC cooling water in the water/coolant heat exchanger 13. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle interior air conditioner / fuel cell cooling device that is mounted on a vehicle using a fuel cell as a driving source for driving and has an air conditioning function in the vehicle interior and also a function of cooling the fuel cell.

  Conventionally, in a fuel cell vehicle using a fuel cell as a driving source for travel, it has been required to maintain the fuel cell at a suitable temperature (for example, 80 ° C.). For this purpose, fuel is produced using circulating cooling water. The battery is designed to cool. Further, vehicle interior air conditioners that perform the air conditioning function in the vehicle interior of the vehicle are widely used.

  In many cases, a radiator for exchanging heat between cooling water for cooling a fuel cell and outside air is arranged on the leeward side of an outdoor unit for air conditioning function with respect to the flow of outside air (for example, Patent Document 1).

  In such a case, since the outside air once passes through the outdoor unit and then reaches the radiator, the temperature of the outside air when reaching the radiator becomes higher than the temperature of the outside air before reaching the outdoor unit. Therefore, in order to sufficiently cool the cooling water of the fuel cell, the radiator must be enlarged.

  As a method for reducing the size of the radiator, Patent Document 2 proposes a technique in which cooling performance is improved by spraying water discharged from the fuel cell to the radiator and using sensible heat and latent heat of the water.

However, since the operating temperature of the fuel cell is about 80 ° C., the saturated vapor pressure is high and most of the water discharged from the fuel cell is water vapor, and the amount of liquid water is small. Therefore, the effect of reducing the size of the radiator by this method is small.
JP 2002-67708 A JP 2002-372385 A

  In view of the above points, the present invention is mounted on a vehicle having a fuel cell as a driving source for traveling, and has an air conditioning function in the passenger compartment, and also has a function of cooling the fuel cell. Even if the radiator for heat exchange between the cooling water for cooling the fuel cell and the outside air is arranged on the leeward side of the outdoor unit for the air conditioning function with respect to the flow of the outside air, the cooling water for the fuel cell The purpose is to increase the cooling effect.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a vehicle interior air conditioner / fuel cell cooling device mounted on a vehicle having the fuel cell (2) as a driving source for driving, for cooling the vehicle interior of the vehicle. A first flow path (10a to 10h) for flowing a coolant for cooling, a second flow path (40a to 40i) for flowing cooling water for cooling the fuel cell, and the first flow path (10a) -10h), the compressor (11) for compressing the refrigerant, and the refrigerant (outside air) disposed in the first flow path (10a to 10h) and increased in temperature by the compressor (11). An outdoor unit (16) that performs heat exchange of the above, a radiator (42) that is disposed in the second flow path (40a to 40i) and performs heat exchange between the cooling water and outside air, and the first In the flow path (10a to 10h), the compressor (1 ), The temperature of the refrigerant before it reaches the outdoor unit (16) is cooled by cooling the fuel cell (2) in the second flow path (40a to 40i) and the radiator (42). ) To the cooling water before arriving at (), a water-refrigerant heat exchanger (13) to be moved, and with respect to the flow of outside air used for heat exchange between the outdoor unit (16) and the radiator (42) The outdoor unit (16) is disposed on the windward side of the radiator (42).

  Thus, the water-refrigerant heat exchanger (13) transfers the heat of the refrigerant before reaching the outdoor unit (16) after the temperature rises by the compressor (11) to the cooling water. Therefore, since the temperature of the refrigerant entering the outdoor unit (16) is lowered, the heat radiation amount of the outdoor unit (16) is reduced. Therefore, the outdoor unit (16) can be thinned. When the thickness of the outdoor unit (16) is reduced, the amount of outside air passing through the outdoor unit (16) increases. When the amount of outside air increases, the temperature rise of the outside air due to passing through the outdoor unit (16) also decreases, so that the outside air temperature entering the radiator (42) decreases. Therefore, the cooling effect of the cooling water of the fuel cell (2) can be enhanced, and as a result, the radiator (42) can be reduced in size.

  In addition, as described in claim 2, the vehicle interior air conditioning / fuel cell cooling device is disposed in the first flow path (10a to 10h), and the heat of the refrigerant whose temperature is increased by the compressor (11). And the first heater core (12) for heating the vehicle interior and the second flow path (40a to 40i) and the cooling water after cooling the fuel cell (2) And a second heater core (48) for heating the vehicle interior using heat.

  In this case, when the vehicle interior is heated by the first heater core (12) and the second heater core (48), the water-refrigerant heat exchanger (13) is connected to the second flow path (13 40a to 40i) become downstream of the second heater core (48), and the water-refrigerant heat exchanger (13) heats the vehicle interior in the first heater core (12). The heat of the refrigerant may be transferred to the cooling water after heating the vehicle interior in the second heater core (48).

  In this way, even when the vehicle interior is heated, in the water-refrigerant heat exchanger (13), the heat of the refrigerant for air conditioning is transferred to the cooling water for the fuel cell (2). Even when the cooling water becomes excessively low for room heating, the temperature of the cooling water can be raised by recovering the excess heat of the air-conditioning refrigerant. Moreover, in the air-conditioning refrigerant, it is possible to prevent deterioration in air-conditioning efficiency due to downsizing of the outdoor unit (16) by passing surplus heat during heating to the cooling water.

  According to a third aspect of the present invention, the vehicle interior air conditioning / fuel cell cooling device includes a water pump (44) for returning the cooling water to the fuel cell (2) in the second flow path (40a to 40i). ) May be provided. The second flow paths (40a to 40i) have branch paths (40d, 40e, 40f, 40g) and a return path (40i), and the branch paths (40d, 40e, 40f, 40g) When cooling the vehicle interior through the water-refrigerant heat exchanger (13) and the second heater core (48), the cooling water that has cooled the fuel cell (2) branches, However, in the branch passages (40d, 40e, 40f, 40g), the water-refrigerant heat exchanger (13) and the second heater core (48) pass in this order, and then merge with the other of the cooling water, When heating the vehicle interior, in the portion including the water-refrigerant heat exchanger (13) and the second heater core (48) in the branch path (40d, 40e, 40f, 40g), Some cooling water is in cooling And the part of the cooling water is led from the branch path (40d, 40e, 40f, 40g) to the suction side of the water pump 44 through the return path (40i), The cooling water may be combined with the remaining cooling water.

  In this way, by using the pressure difference between the outlet of the fuel cell (2) and the inlet of the water pump (44) in the second flow path (40a to 40i), the cooling is performed. Sometimes, it is not necessary to separately provide a water pump for flowing cooling water to the second heater core (48) and the water-refrigerant heat exchanger (13), and power consumption can be suppressed.

  In addition, the code | symbol in the bracket | parenthesis in the said and the claim shows the correspondence of the term described in the claim, and the concrete thing etc. which illustrate the said term described in embodiment mentioned later. .

  The first embodiment of the present invention will be described below. FIG. 1 shows configurations of a vehicle interior air conditioning / fuel cell cooling device 1 and a fuel cell 2 according to the present embodiment. A vehicle interior air-conditioning / fuel cell cooling device 1 and a fuel cell 2 shown in FIG. 1 are mounted on the vehicle.

  The vehicle interior air conditioning / fuel cell cooling device 1 is a device that realizes an air conditioning function in the vehicle interior and a function of cooling the fuel cell. The fuel cell 2 is a battery that generates electricity by causing an electrochemical reaction between an oxidant gas and a fuel gas, and functions as a driving source for driving the vehicle.

  The fuel cell 2 generates electric power by utilizing an electrochemical reaction between hydrogen and oxygen. In this embodiment, a solid polymer electrolyte type fuel cell is used as the fuel cell 2, and a plurality of cells serving as basic units are stacked. The present invention can also be applied to fuel cells other than the solid polymer electrolyte type.

In the fuel cell 2, the following electrochemical reaction between hydrogen and oxygen occurs to generate power. Note that hydrogen corresponds to the fuel gas of the present invention, and oxygen (air) corresponds to the oxidant gas of the present invention.
Anode (hydrogen electrode) 2H ₂ → 4H + + 4e-
Cathode (oxygen electrode) 4H ++ O ₂ + 4e− → 2H ₂ O
Overall 2H ₂ + O2 → 2H ₂ O
The fuel cell 2 generates heat with power generation. For this reason, the vehicle interior air-conditioning / fuel cell cooling device 1 circulates cooling water (hereinafter referred to as FC cooling water) to cool the fuel cell 2 so that the operating temperature is efficient (around 80 ° C.). It is trying to become. As the FC cooling water, for example, an ethylene glycol aqueous solution can be used.

  The vehicle interior air conditioning / fuel cell cooling device 1 includes an air conditioning flow path (corresponding to a first flow path) through which a refrigerant (hereinafter referred to as air conditioning refrigerant) for cooling and heating the vehicle interior of the vehicle, and fuel It has an FC cooling flow path (corresponding to the second flow path) for flowing FC cooling water for cooling the battery. More specifically, it has piping for forming the air conditioning channel and the FC cooling channel.

  Further, the vehicle interior air conditioning / fuel cell cooling device 1 includes a compressor 11, a heating indoor unit 12, a shut valve 14, an expansion valve 15, an outdoor unit 16, a shut valve 17, a shut valve 18, which are disposed in an air conditioning flow path. An expansion valve 19 and a cooling indoor unit 20 are provided. Further, the vehicle interior air conditioning / fuel cell cooling device 1 is different from the vehicle interior air conditioning / fuel cell cooling device 1 in the radiator 42, the three-way valve 43, the water pump 44, the three-way valve 45, and the shut valve 46. The water pump 47 and the heater core 48 are provided. Further, the vehicle interior air conditioning / fuel cell cooling device 1 has one water-refrigerant heat exchanger 13 disposed in both the air conditioning channel and the FC cooling channel. The vehicle interior air conditioning / fuel cell cooling device 1 further includes a vehicle interior blower fan 31, an outside air introduction fan 32, and an air mix door 33.

  Further, the vehicle interior air conditioning / fuel cell cooling device 1 includes an air conditioning case 30 that constitutes an air passage through which air conditioning air supplied to the vehicle interior flows. In the air conditioning case 30, the above-described vehicle interior fan 31, the heating indoor unit 12, the cooling indoor unit 20, the heater core 48, and the air mix door 33 are provided.

  The compressor 11 is a device that sucks air-conditioning refrigerant in the air-conditioning flow path and compresses and discharges the sucked air-conditioning refrigerant. The temperature of the discharged air-conditioning refrigerant increases as compared with that before suction. The heating indoor unit 12 is a heat exchanger, that is, a heater core, for heating the air flowing into the vehicle interior by performing heat exchange between the air flowing into the vehicle interior and the compressed air-conditioning refrigerant.

  The water-refrigerant heat exchanger 13 is a heat exchanger that transfers heat from the higher temperature to the lower temperature between the air-conditioning refrigerant and the FC cooling water. The shut valves 14, 17, 18, 46 are valves that can be switched between open and closed. The expansion valves 15 and 19 are valves that suck in the air-conditioning refrigerant in the air-conditioning flow path and decompress the sucked air-conditioning refrigerant.

  The outdoor unit 16 is a heat exchanger that exchanges heat between the outside air and the air-conditioning refrigerant using outside air passing through the outdoor unit 16 (that is, air outside the vehicle). Heat is dissipated, and the air-conditioning refrigerant absorbs heat when heating the passenger compartment. The radiator 42 is a heat exchanger that radiates the FC cooling water by performing heat exchange between the outside air and the FC cooling water using the outside air passing through the radiator 42.

  The outdoor unit 16 and the radiator 42 are arranged in series with respect to a direction 50 in which outside air used for heat exchange flows. More specifically, the outdoor unit 16 is disposed on the windward side of the radiator 42. Therefore, the outside air reaches the radiator 42 after passing through the outdoor unit 16.

  The cooling indoor unit 20 is a heat exchanger for cooling the air flowing into the vehicle interior by performing heat exchange between the air flowing into the vehicle interior and the decompressed air-conditioning refrigerant. The three-way valves 43 and 45 are connected to the FC cooling water flow path in three directions, and the open / close state can be changed so that the FC cooling water can flow between any two of the three directions. It is a valve.

  The water pumps 44 and 47 are devices that pump FC cooling water by actively sucking and discharging the FC cooling water in the FC cooling flow path, thereby increasing the flow rate of the FC cooling water. The water pump 44 functions as a power source for returning the FC cooling water to the fuel cell 2. The heater core 48 is a heat exchanger for heating the air flowing into the vehicle interior by exchanging heat between the air flowing into the vehicle interior and the FC cooling water.

  The vehicle interior blowing fan 31 is a blower for sending air into the vehicle interior. The outside air introduction fan 32 is a fan for flowing outside air in the direction 50 from the outdoor unit 16 to the radiator 42. The air mix door 33 is an open / close door that controls a path through which air-conditioning air sent to the vehicle interior by the vehicle interior blower fan 31 passes.

  Here, the arrangement relationship among the indoor unit 12 for heating, the air mix door 33, and the heater core 48 will be described. These members 12, 33, and 48 are arranged in series in order of the air mix door 33, the heater core 48, and the heating indoor unit 12 in order from the upstream with respect to the air-conditioning air flowing into the vehicle interior from the vehicle interior fan 31. ing. Accordingly, when the air-conditioning air passes through the heater core 48 and the heating indoor unit 12, the air-conditioning air first passes through the heater core 48, and the air-conditioning air after passing through the heater core 48 passes through the heating indoor unit 12. .

  Moreover, the air-conditioning flow path has flow paths 10a to 10h. The flow path 10 a extends from the discharge side of the compressor 11 to the indoor unit 12. The flow path 10 b extends from the indoor unit 12 to the water-refrigerant heat exchanger 13. The flow path 10c extends from the water-refrigerant heat exchanger 13 and branches into two, and extends to the shut valve 14 and the expansion valve 15, respectively. The flow path 10d extends from each of the shut valve 14 and the expansion valve 15 to join each other, and extends to the outdoor unit 16 after joining.

  The flow path 10 e extends from the outdoor unit 16 to the indoor unit 20. And the shut valve 18 is arrange | positioned in the middle of the flow path 10e. Further, an expansion valve 19 is disposed in the middle of the flow path 10 e and between the shut valve 18 and the indoor unit 20.

  Further, the flow path 10 f extends from the position of the flow path 10 e between the outdoor unit 16 and the shut valve 18 to the suction side of the compressor 11. And the shut valve 17 is arrange | positioned in the middle of the flow path 10f. Further, the flow path 10 h extends from the indoor unit 20 to between the shut valve 17 and the compressor 11 in the flow path 10 f.

  The FC cooling flow path has flow paths 40a to 40i. The flow path 40 a extends from the fuel cell 2 to the radiator 42. The flow path 40 h extends from the radiator 42 to the three-way valve 43. The flow path 40 b extends from the three-way valve 43 to the fuel cell 2. A water pump 44 that pumps FC cooling water toward the fuel cell 2 is disposed in the flow path 40b.

  Further, the flow path 40 c is arranged from the middle of the flow path 40 a to the three-way valve 43. Further, in the flow path 40b, the flow path 40i extends from between the three-way valve 43 and the water pump 44 to the three-way valve 45. A flow path 40d extends from the three-way valve 45 to the middle of the flow path 40a. It should be noted that the junction point between the channel 40a and the channel 40d is closer to the fuel cell 2 than the junction point between the channel 40a and the channel 40c.

  Further, the flow path 40e exits from the three-way valve 45, branches into two, passes through the shut valve 46 and the water pump 47, and then joins, and after joining, extends to the water-refrigerant heat exchanger 13. The flow path 40 f extends from the water-refrigerant heat exchanger 13 to the heater core 48. The flow path 40g extends from the heater core 48 to the middle of the flow path 40a. Note that the confluence of the flow path 40a and the flow path 40g is closer to the fuel cell 2 than the confluence of the flow path 40a and the flow path 40c, and moreover than the confluence of the flow path 40a and the flow path 40b. Located on the radiator 42 side.

  Moreover, the vehicle interior air conditioning / fuel cell cooling device 1 includes an ECU 100 shown in FIG. The ECU 100 has a known microcomputer provided with a CPU, RAM, ROM and the like. Various operations of the ECU 100 are realized by the CPU executing the program read from the ROM to the RAM. In the present embodiment, the ECU 100 operates when the compressor 11, the shut valve 14, the expansion valve 15, the shut valve 17, the shut valve 18, the vehicle interior blower fan 31, the outside air introduction fan 32, the air mix door 33, These devices are controlled by outputting control signals to the three-way valve 43, the water pump 44, the three-way valve 45, the shut valve 46, and the water pump 47.

  The vehicle interior air conditioning / fuel cell cooling device 1 has a water temperature sensor (not shown). This water temperature sensor detects the temperature of the FC cooling water in the portion of the flow path 40a from the fuel cell 2 to the branch point to the flow path 40d, and outputs the detected temperature to the ECU 100 as a detection signal. It has become.

  Hereinafter, the operation of the vehicle interior air conditioning / fuel cell cooling device 1 having the above-described configuration will be described separately for the case of cooling the vehicle interior and the case of heating. The ECU 100 determines whether to perform cooling and whether to perform heating according to the operation content of the occupant on the operation device (not shown).

(1) During cooling (see FIG. 3):
When the vehicle interior is cooled, the ECU 100 operates the compressor 11, opens the shut valve 14, deactivates the expansion valve 15, closes the shut valve 17, opens the shut valve 18, and opens the interior fan 31. , The outside air introduction fan 32 is activated, the water pump 44 is activated, the shut valve 46 is closed, and the water pump 47 is activated.

  Further, at this time, the ECU 100 maintains the water temperature of the FC cooling water from the fuel cell 2 in the vicinity of the optimum temperature (for example, 80 ° C.) for the fuel cell operation based on the detection signal output from the water temperature sensor. Thus, the open / close state of the three-way valve 43 is feedback-controlled.

  Specifically, when the water temperature indicated by the detection signal output from the water temperature sensor exceeds a threshold temperature (for example, a temperature 5 ° C. higher than the optimum temperature), the ECU 100 controls the open / close state of the three-way valve 43 to The FC cooling water flows between 40h and the flow path 40b, and the FC cooling water is prevented from flowing through the flow path 40c. That is, the control is performed so that the FC cooling water is cooled through the radiator 42.

  Further, when the water temperature indicated by the detection signal output from the water temperature sensor falls below the threshold temperature, the open / close state of the three-way valve 43 is controlled, and the FC cooling water flows between the flow path 40c and the flow path 40b. The FC cooling water is prevented from flowing through the passage 40h. That is, control is performed so that the FC cooling water does not pass through the radiator 42.

  At this time, the ECU 100 controls the open / closed state of the three-way valve 45 so that the FC cooling water flows between the flow paths 40d and 40e and the FC cooling water does not flow through the flow paths 40i. At this time, the ECU 100 controls the air mix door 33 so that the air flowing into the vehicle compartment passes through the cooling indoor unit 20 and does not pass through the heater core 48 and does not pass through the heating indoor unit 12.

  In this case, in the air conditioning flow path, the air conditioning refrigerant is compressed by the compressor 11 and rises in temperature, and then enters the heating indoor unit 12 through the flow path 10a and exits from the heating indoor unit 12 through the flow path 10b. The water-refrigerant heat exchanger 13 is entered.

  The temperature of the air-conditioning refrigerant discharged from the compressor 11 is about 120 ° C., for example. Since the air flowing into the passenger compartment does not pass through the heating indoor unit 12 during cooling, the air-conditioning refrigerant reaches the water-refrigerant heat exchanger 13 while the temperature hardly decreases even when passing through the heating indoor unit 12.

  In the water-refrigerant heat exchanger 13, the air-conditioning refrigerant exchanges heat with FC cooling water (for example, 80 ° C.) having a temperature lower than that of the air-conditioning refrigerant, as will be described later. As a result, heat (that is, thermal energy) moves from the air-conditioning refrigerant to the FC cooling water, and the temperature of the air-conditioning refrigerant decreases (for example, to 100 ° C.).

  The air-conditioning refrigerant that has exited the water-refrigerant heat exchanger 13 enters the channel 10d through the shut valve 14 from the channel 10c and further enters the outdoor unit 16. In the outdoor unit 16, the air-conditioning refrigerant and the outside air exchange heat, so that the air-conditioning refrigerant dissipates heat, and the temperature of the air-conditioning refrigerant decreases to a temperature slightly higher than the outside air temperature (for example, 30 ° C.).

  The air-conditioning refrigerant that has exited the outdoor unit 16 passes through the shut valve 18 in the flow path 10e and is depressurized by the expansion valve 19 to drop in temperature and enter the cooling indoor unit 20. In the cooling indoor unit 20, the air entering the passenger compartment and the air conditioning refrigerant exchange heat, whereby the air conditioning refrigerant evaporates and takes the heat of the air. The air-conditioning refrigerant exiting the cooling indoor unit 20 enters the flow path 10f through the flow path 10h, and then returns to the compressor 11.

  In this case, in the FC cooling flow path, FC cooling water whose temperature has been increased by cooling the fuel cell 2 (for example, up to 80 ° C.) enters the flow path 40a. The flow rate of the FC cooling water entering this flow path 40a is, for example, 100 liters / minute. Part of the FC cooling water that has entered the flow path 40a (for example, 1/10) enters the flow path 40d at the junction of the flow path 40a and the flow path 40d, and the rest proceeds through the flow path 40a.

  The FC cooling water that has entered the flow path 40d passes through the three-way valve 45, enters the flow path 40e, is pumped by the waterpo 7, and then enters the water-refrigerant heat exchanger 13. The temperature of the FC cooling water when it reaches the water-refrigerant heat exchanger 13 (for example, 80 ° C.) is lower than the temperature of the air-conditioning refrigerant that has entered the water-refrigerant heat exchanger 13. Therefore, as described above, heat is transferred from the air-conditioning refrigerant to the FC cooling water by heat exchange, and as a result, the temperature of the FC cooling water rises (for example, from 82 ° C. to 83 ° C.).

  The FC cooling water exiting the water-refrigerant heat exchanger 13 enters the heater core 48 through the flow path 40f. Since the air flowing into the passenger compartment does not pass through the heater core 48 during cooling, the FC cooling water enters the flow path 40g with the temperature hardly decreasing even after passing through the heater core 48, and then merges with the flow path 40a.

  The FC cooling water after the merge (for example, temperature 81 to 81.5 ° C.) enters the radiator 42 through the flow path 40a or passes through the flow path 40c depending on the open / close state of the three-way valve 43. 42 is bypassed and enters the flow path 40b.

  When entering the radiator 42 through the flow path 40a, in the radiator 42, the FC cooling water and the outside air exchange heat, whereby the FC cooling water dissipates heat, and the temperature of the FC cooling water decreases. The FC cooling water exiting the radiator 42 passes through the flow path 40h, the three-way valve 43, and the flow path 40b in this order, is further pumped by the water pump 44, and returns to the fuel cell 2 again to cool the fuel cell 2. .

  In this way, during cooling, the air-conditioning refrigerant before reaching the outdoor unit 16 after the temperature rises by the compressor 11 enters the water-refrigerant heat exchanger 13, and after cooling the fuel cell 2 to the radiator 42. The FC cooling water before reaching the water-refrigerant heat exchanger 13. And in the water-refrigerant heat exchanger 13, heat moves from the air-conditioning refrigerant to the FC cooling water.

  Therefore, compared with the case where heat exchange is not performed in the water-refrigerant heat exchanger 13, the temperature of the air-conditioning refrigerant entering the outdoor unit 16 is lowered, and thus the heat radiation amount of the outdoor unit 16 is reduced. Therefore, the outdoor unit 16 can be reduced in thickness, and is actually reduced in thickness. That is, the thickness of the outdoor unit 16 in the direction of the inflow direction 50 of the outside air is smaller than that of the related art.

  The amount of outside air that passes through the outdoor unit 16 (specifically, the flow rate per unit time) increases as the thickness of the outdoor unit 16 is reduced. When the amount of the outside air passing through the outdoor unit 16 increases, the temperature increase amount of the outside air due to passing through the outdoor unit 16 also decreases, so that the temperature of the outside air entering the radiator 42 decreases. Therefore, the cooling effect of the cooling water of the fuel cell 2 can be enhanced, and as a result, the radiator 42 can also be reduced in size.

  As described above, in the FC cooling channel, the FC cooling water is branched at the junction of the channel 40a and the channel 40d, one of them is heated by the water-refrigerant heat exchanger 13, and then merged. Yes. This is because when all of the air-conditioning refrigerant flows into the water-refrigerant heat exchanger 13, the flow rate of the air-conditioning refrigerant decreases due to resistance in the water-refrigerant heat exchanger 13 and the heating indoor unit 12. Because. However, if the flow rate of the air-conditioning refrigerant may decrease, all of the air-conditioning refrigerant may flow into the water-refrigerant heat exchanger 13.

(2) During heating (see Fig. 4):
When heating the passenger compartment, the ECU 100 operates the compressor 11, closes the shut valve 14, operates the expansion valve 15, opens the shut valve 17, closes the shut valve 18, and closes the blower fan 31 in the passenger compartment. The external air introduction fan 32 is activated, the water pump 44 is activated, the shut valve 46 is opened, and the water pump 47 is deactivated.

  At this time, the ECU 100 determines that the temperature of the FC cooling water from the fuel cell 2 is the optimum temperature for operating the fuel cell (for example, 80 ° C.) based on the detection signal output from the water temperature sensor, as in the case of cooling. The feedback control is performed on the open / closed state of the three-way valve 43 so as to be maintained in the vicinity. However, it is rarely necessary to control the three-way valve 43 so that the FC cooling water passes through the radiator 42 during heating.

  At this time, the ECU 100 controls the open / closed state of the three-way valve 45 so that the FC cooling water flows between the flow paths 40i and 40e and the FC cooling water does not flow through the flow paths 40d. At this time, the ECU 100 controls the air mix door 33 so that the air-conditioning air flowing into the vehicle compartment passes through the cooling indoor unit 20, the heater core 48, and then the heating indoor unit 12.

  In this case, in the air conditioning flow path, the air-conditioning refrigerant is compressed by the compressor 11 (for example, up to 120 ° C.) and rises in temperature, and then enters the heating indoor unit 12 through the flow path 10a.

  Since the air flowing into the vehicle compartment passes through the heating indoor unit 12, the air-conditioning refrigerant heats the air flowing into the vehicle interior by exchanging heat with the air in the heating indoor unit 12. Thereby, the air-conditioning refrigerant dissipates heat, and the temperature of the air-conditioning refrigerant decreases (for example, from 30 ° C. to 40 ° C.). And the air-conditioning refrigerant | coolant which temperature fell enters the water-refrigerant heat exchanger 13 through the flow path 10b.

  In the water-refrigerant heat exchanger 13, the air-conditioning refrigerant exchanges heat with FC cooling water (for example, 10 ° C.) having a temperature lower than that of the air-conditioning refrigerant as will be described later. As a result, heat is transferred from the air-conditioning refrigerant to the FC cooling water, and the temperature of the air-conditioning refrigerant is reduced (for example, to 20 ° C.).

  The air-conditioning refrigerant that has exited the water-refrigerant heat exchanger 13 enters the expansion valve 15 from the flow path 10c and is depressurized. The air-conditioning refrigerant that has been decompressed and lowered to a temperature lower than the outside air temperature (for example, a temperature that is 2 ° C. to 3 ° C. lower than the outside air temperature) enters the outdoor unit 16 through the flow path 10d. In the outdoor unit 16, the air-conditioning refrigerant exchanges heat with the outside air, so that the air-conditioning refrigerant takes heat from the outside air, and the air-conditioning refrigerant changes phase from the liquid phase to the gas phase. The air-conditioning refrigerant exiting from the outdoor unit 16 then enters the shut valve 17 through the flow path 10e, and further reaches the compressor 11 through the flow path 10f.

  In this case, in the FC cooling channel, FC cooling water whose temperature has been increased by cooling the fuel cell 2 (for example, up to 80 ° C.) enters the channel 40a. The flow rate of the FC cooling water entering this flow path 40a is, for example, 100 liters / minute. Part of the FC cooling water that has entered the flow path 40a (for example, 1/10) enters the flow path 40g at the junction of the flow path 40a and the flow path 40g, and the rest proceeds through the flow path 40a. The flow of FC cooling water that does not enter the flow path 40g and proceeds through the flow path 40a is the same as that during cooling.

  The FC cooling water that has entered the flow path 40 g enters the heater core 48. Since the air flowing into the vehicle interior passes through the heater core 48, the FC cooling water heats the air flowing into the vehicle interior by exchanging heat with the air in the heater core 48. Thereby, the FC cooling water dissipates heat, and the temperature of the FC cooling water decreases (for example, to 10 ° C.). Then, the FC cooling water whose temperature has decreased enters the water-refrigerant heat exchanger 13 through the flow path 40f.

  As described above, the temperature of the FC cooling water when it reaches the water-refrigerant heat exchanger 13 (for example, 10 ° C.) is the temperature of the air-conditioning refrigerant that has entered the water-refrigerant heat exchanger 13 (for example, 30 ° C. to 40 ° C.). Lower). That is, the temperature of the FC cooling water after passing through the heater core 48 is lower than the temperature of the air-conditioning refrigerant after passing through the heating indoor unit 12.

  This temperature relationship is due to the following three reasons. The first reason is that the temperature of the FC cooling water immediately before entering the heater core 48 is higher than the temperature of the air-conditioning refrigerant before entering the heating indoor unit 12. The second reason is that the portion of the FC cooling water that enters the heater core 48 is only a small part (for example, 1/10) of the entire FC cooling water, so that it is easy to cool rapidly.

  The third reason is the arrangement of the heater core 48 and the heating indoor unit 12. That is, the heater core 48 is upstream of the heating indoor unit 12 with respect to the flow of the air conditioning air, and the air conditioning air passes through the heater core 48 and then passes through the heating indoor unit 12. Therefore, the air for air conditioning passes through the heating indoor unit 12 after being heated by the FC cooling water in the heater core 48. That is, the temperature of the air for air conditioning is higher when passing through the heating indoor unit 12 than when passing through the heater core 48. As a result, the FC cooling water is cooled more strongly than the air-conditioning refrigerant. Therefore, the temperature of the FC cooling water after passing through the heater core 48 is lower than the temperature of the air-conditioning refrigerant after passing through the heating indoor unit 12.

  Thus, the temperature of the FC cooling water when it reaches the water-refrigerant heat exchanger 13 (for example, 10 ° C.) is the temperature of the air-conditioning refrigerant that has entered the water-refrigerant heat exchanger 13 (for example, 30 ° C. to 40 ° C.). Lower than. Therefore, as described above, heat is transferred from the air-conditioning refrigerant to the FC cooling water by heat exchange, and as a result, the temperature of the FC cooling water rises.

  The FC cooling water exiting the water-refrigerant heat exchanger 13 enters the three-way valve 45 through the shut valve 46 of the flow path 40e, and then joins the flow path 40h through the flow path 40i. The fuel cell 2 is cooled by returning to the fuel cell 2 again.

  Thus, when the vehicle interior is heated by the heating indoor unit 12 and the heater core 48, the water-refrigerant heat exchanger 13 is on the downstream side of the heater core 48 in the FC cooling flow path. On the other hand, as described above, FC cooling water flows from the water-refrigerant heat exchanger 13 toward the heater core 48 during cooling. Therefore, the upstream-downstream relationship between the water-refrigerant heat exchanger 13 and the heater core 48 is reversed during cooling and heating.

  The water-refrigerant heat exchanger 13 moves the heat of the air-conditioning refrigerant after heating the vehicle interior in the heating indoor unit 12 to the cooling water after heating the vehicle interior in the heater core 48. Yes. The reason why the temperature of the air-conditioning refrigerant is higher than that of the FC cooling water during heating in the water-refrigerant heat exchanger 13 is that the air-conditioning refrigerant becomes hotter than the temperature of the fuel cell 2 by the compressor 11, Both of the air-conditioning refrigerants are used for heating the passenger compartment and lower the temperature.

  With this configuration, when the vehicle interior is heated, the heat of the air-conditioning refrigerant is transferred to the FC cooling water for the fuel cell 2 in the water-refrigerant heat exchanger 13. Therefore, even if the cooling water becomes excessively low, the temperature of the cooling water can be raised by recovering the excess heat of the air conditioning refrigerant. In the air conditioning refrigerant, surplus heat at the time of heating is passed to the FC cooling water, so that deterioration in air conditioning efficiency due to downsizing of the outdoor unit 16 can be prevented.

  Further, the ECU 100 of the vehicle interior air conditioning / fuel cell cooling device 1 causes the FC cooling water to branch in the FC cooling flow path during cooling, and one of them is connected to the water pump 47, the water-refrigerant heat exchanger 13, and the heater core 48. It flows through the branch paths 40d, 40e, 40f, and 40g that are sequentially passed, and then merges with the other. During heating, the ECU 100 causes a portion of the FC cooling water to flow in a direction opposite to that during cooling in a portion including the water-refrigerant heat exchanger 13 and the heater core 48 in the branch path. The FC cooling water is guided from the branch path to the suction side of the water pump 44 through the flow path 40i (corresponding to an example of the return path), where it is merged with the remaining FC cooling water.

  In this way, by utilizing the pressure difference between the outlet of the fuel cell 2 in the FC cooling flow path and the inlet of the water pump 44, the heater core 48 and the water-refrigerant heat exchange are performed during cooling. It is not necessary to separately provide a water pump for flowing cooling water to the vessel 13, and power consumption can be suppressed.

(Other embodiments)
As mentioned above, although embodiment of this invention was described, the scope of the present invention is not limited only to the said embodiment, The various form which can implement | achieve the function of each invention specific matter of this invention is included. It is.

  For example, in the above-described embodiment, the three-way valve 45 is used to realize an operation in which the flow path 40d and the flow path 40e are communicated during cooling and the flow path 40i and the flow path 40e are communicated during heating. However, other than the three-way valve 45 may be used as long as such an operation can be realized.

  Further, for example, when heating the passenger compartment, the ECU 100 controls the open / close state of the three-way valve 43 when the temperature of the fuel cell 2 exceeds a predetermined temperature, so that the flow path between the flow path 40h and the flow path 40b is controlled. The FC cooling water may flow, and the FC cooling water may flow through the flow path 40c. By doing in this way, FC cooling water is cooled because FC cooling water passes the radiator 42 also at the time of heating.

It is a figure which shows the structure of the vehicle interior air conditioner and the fuel cell cooling device. It is a block diagram which shows the control object of ECU100. It is a figure which shows the action | operation of the vehicle interior air conditioning and the fuel cell cooling device 1 at the time of air_conditioning | cooling. It is a figure which shows the action | operation of the vehicle interior air conditioning and the fuel cell cooling device 1 at the time of heating.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Car interior air conditioning and fuel cell cooling device 2 Fuel cell 10a-10h Air-conditioning flow path 11 Compressor 12 Heating indoor unit 13 Water-refrigerant heat exchangers 14, 17, 18, 46 Shut valve 15, 19 Expansion valve 16 Outdoor unit 20 Cooling indoor unit 31 Blower fan 32 Outside air introduction fan 33 Air mix doors 40a to 40i Cooling flow path 42 Radiators 43 and 45 Three-way valve 43
44, 47 Water pump 48 Heater core 50 Inflow direction of outside air 100 ECU

Claims (3)

A vehicle interior air conditioning / fuel cell cooling device mounted on a vehicle using the fuel cell (2) as a driving source for traveling,
A first flow path (10a to 10h) for flowing a refrigerant for cooling the passenger compartment of the vehicle;
A second flow path (40a to 40i) for flowing cooling water for cooling the fuel cell;
A compressor (11) disposed in the first flow path (10a to 10h) and compressing the refrigerant;
An outdoor unit (16) that is arranged in the first flow path (10a to 10h) and performs heat exchange between the refrigerant whose temperature has been raised by the compressor (11) and the outside air;
A radiator (42) disposed in the second flow path (40a to 40i) and performing heat exchange between the cooling water and outside air;
After the temperature rises by the compressor (11) in the first flow path (10a to 10h), the heat of the refrigerant before reaching the outdoor unit (16) is converted into the second flow path (40a to 40i). And a water-refrigerant heat exchanger (13) to be moved to the cooling water after cooling the fuel cell (2) before reaching the radiator (42),
The outdoor unit (16) is arranged on the windward side of the radiator (42) with respect to the flow of outside air used for heat exchange between the outdoor unit (16) and the radiator (42). Air conditioning / fuel cell cooling system. A first heater core (12) disposed in the first flow path (10a to 10h) for heating the vehicle interior with heat of the refrigerant whose temperature has been raised by the compressor (11);
A second heater core (48) that is disposed in the second flow path (40a to 40i) and that heats the vehicle interior using heat of the cooling water after cooling the fuel cell (2). ) And
When the vehicle interior is heated by the first heater core (12) and the second heater core (48), the water-refrigerant heat exchanger (13) is connected to the second flow path (40a to 40i). ) On the downstream side of the second heater core (48), and the water-refrigerant heat exchanger (13) heats the refrigerant after heating the vehicle interior in the first heater core (12). 2. The vehicle interior air conditioning / fuel cell cooling device according to claim 1, wherein the second heater core is moved to the cooling water after the vehicle interior is heated in the second heater core. A water pump (44) for returning the cooling water to the fuel cell (2) in the second flow path (40a to 40i);
The second flow path (40a to 40i) has a branch path (40d, 40e, 40f, 40g) and a return path (40i),
The branch passages (40d, 40e, 40f, 40g) pass through the water-refrigerant heat exchanger (13) and the second heater core (48),
When the vehicle interior is cooled, the cooling water that has cooled the fuel cell (2) branches, and one of the cooling water exchanges the water-refrigerant heat exchange in the branch passages (40d, 40e, 40f, 40g). Passing through the vessel (13) and the second heater core (48) in this order, and then joining the other of the cooling water,
When heating the vehicle interior, in the portion including the water-refrigerant heat exchanger (13) and the second heater core (48) in the branch path (40d, 40e, 40f, 40g), A part of the cooling water flows in a direction opposite to that during cooling, and the part of the cooling water passes through the return path (40i) from the branch path (40d, 40e, 40f, 40g) and the water pump. The vehicle interior air conditioning / fuel cell cooling device according to claim 2, wherein the vehicle interior air conditioning / fuel cell cooling device is combined with the remaining cooling water by being guided to the suction side of 44.

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