JP5011980B2 - Coordinated cooling system for fuel cell and air conditioning - Google Patents

Description

  The present invention relates to a coordinated cooling system for a fuel cell and an air conditioner, and more particularly to a coordinated cooling system for a fuel cell and an air conditioner that performs coordinated control by sharing a refrigerant between the fuel cell cooling system and the air conditioning cooling system.

  Since there is little impact on the environment, fuel cells are installed in vehicles. In the fuel cell, for example, a fuel gas such as hydrogen is supplied to the anode side of the fuel cell stack, an oxidizing gas containing oxygen such as air is supplied to the cathode side, and necessary electric power is taken out by a reaction through the electrolyte membrane. The fuel cell generates heat due to this reaction, and a coolant such as cooling water is allowed to flow through the fuel cell stack for cooling, and this is cooled with a radiator or the like. When the temperature of the fuel cell is low, the refrigerant is heated to an appropriate temperature with a heater or the like in order to warm the fuel cell. In this way, the refrigerant is allowed to flow through the fuel cell stack and its temperature is adjusted.

  In general, a heat pump system that performs a compression and evaporation cycle of refrigerant gas can be used for cooling and heating the interior of a vehicle. However, waste of refrigerant such as cooling water used for cooling the fuel cell stack can be used. Heat can also be used.

  For example, Patent Document 1 describes the configuration of a vehicle air conditioner that uses a coolant circulation system for a fuel cell and a refrigerant circulation system for vehicle interior air conditioning. Vehicle interior air conditioning is performed by an indoor heat exchanger through which air-conditioning refrigerant passes and a hot water heater core that warms the air with hot water, and air conditioning is switched by heating the indoor heat exchanger through high-pressure refrigerant by operating a four-way valve, It is performed by cooling through a low-pressure refrigerant. Here, it is disclosed that the cooling water circulation system of the fuel cell can be separated into two of the first hot water circuit and the second hot water circuit by opening and closing two on-off valves, or these hot water circuits can be connected. Has been. When separated, the first hot water circuit can raise the water temperature by the waste heat of the fuel cell because the cooling water discharged from the fuel cell returns to the fuel cell again. When separated, the second hot water circuit circulates between the water refrigerant heat exchanger that exchanges heat between the circulating water and the high pressure refrigerant for air conditioning in the vehicle interior and the hot water heater core. The cooling water is heated, and the temperature of the hot water in the hot water heater core can be raised. When the two hot water circuits are connected, the cooling water is heated not only by the heat radiation of the air conditioning high-pressure refrigerant but also by the waste heat of the fuel cell and supplied to the hot water heater core. In addition, although the name of a heater core is used here, it does not have what is called an electric heater but is used to warm air using the heat of hot water. it can.

JP 2005-263200 A

  As described above, cooperative control of the fuel cell and the air conditioning is performed using the waste water of the cooling water circulation system of the fuel cell for the air conditioning in the vehicle interior using the hot water heat core. Here, the heat core functions as a heater that heats the air using the heat of hot water, but from another point of view, the heat core dissipates heat from the cooling water of the fuel cell simultaneously with heating. It also has a function. Therefore, it is convenient if the heat dissipation function of the heat core can be used when the heat dissipation capability of the radiator that is the cooling system on the fuel cell side is insufficient, such as in summer. However, since the heat core is also a heater, if it is left as it is, for example, heating will enter in the summer, which is inconvenient.

  An object of the present invention is to provide a fuel cell and air conditioning cooperative cooling system that can use a heat core as a radiator.

A coordinated cooling system for a fuel cell and an air conditioner according to the present invention is a coordinated cooling system that performs coordinated control by sharing a refrigerant between a fuel cell cooling system and an air conditioning cooling system, and is provided between a fuel cell stack and a radiator. The fuel cell-side circulation channel for circulating the refrigerant in the air-conditioner, the air-conditioning-side heat exchange channel for arranging the heat core that exchanges heat between the refrigerant and the air flow, and the connection flow that connects both ends of the air-conditioning-side heat exchange channel interrupting the air-conditioning-side circulation flow path, a control valve provided between the fuel cell side circulation flow path and the air-conditioning-side circulation flow path, and a fuel cell side circulation passage and the air conditioning side circulation flow path having a road Open the connection channel of the air conditioning side circulation channel and connect the air conditioning side heat exchange channel in parallel with the fuel cell side circulation channel to share the fuel cell side refrigerant and the air conditioning side refrigerant Control valve for switching between connected state and heat exchange with heat core The direction of blowing of, comprising a blowing switching means for switching on the inside and outside, the control valve is regardless of whether the air conditioning side of the heating demand, in accordance with the temperature of the fuel cell side refrigerant, the fuel cell side circulation The flow path and the air conditioning side circulation flow path are switched from a cut-off state to a connected state, the heat of the fuel cell side refrigerant is radiated through the heat core, and the fuel cell side circulation flow path and the air conditioning side circulation flow path are When the air conditioner side is switched from the shut-off state to the connected state, and there is a cooling request on the air conditioning side, the air blowing switching means switches the direction of the air blowing to the outside and transfers the heat of the fuel cell side refrigerant to the outside air via the heat core. It is radiated to the characterized Rukoto.

Further, in the fuel cell and air conditioning cooperative control system according to the present invention, when the control valve is switched from the cutoff state to the connected state between the fuel cell side circulation passage and the air conditioning side circulation passage , the air conditioning side When there is no cooling request, it is preferable that the air blowing switching means switch the air blowing direction into the room and dissipate the heat of the fuel cell side refrigerant into the room through the heat core.

In the fuel cell and air conditioning cooperative control system according to the present invention, the control valve includes three flow paths: a branch flow path from the fuel cell side circulation flow path, the air conditioning side heat exchange flow path, and the connection flow path. three-way valve der Rukoto provided at the connection point to gather are preferred.

  With the above configuration, the coordinated cooling system for the fuel cell and the air conditioner has the air blowing switching means for switching the direction of the air blowing after heat exchange with the heat core between the room and the outdoor. For example, by switching the air flow depending on whether or not the function of the heat core as a heater is used, the heat dissipation function of the heat core can be fully utilized.

  In addition, the control valve switches from the shut-off state to the connected state according to the temperature of the fuel cell side refrigerant regardless of whether the air conditioning side has a heating request, and dissipates the heat of the fuel cell side refrigerant through the heat core. The heat core can be used as the second radiator when the heat dissipation capability of the radiator, which is the fuel cell side cooling system, is insufficient.

  In addition, since the direction of the air flow is switched to the outside and the heat of the fuel cell side refrigerant is dissipated to the outside air through the heat core, the heat core heat dissipation function can be used even when the air conditioning system does not require heating. .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Below, although demonstrated as what uses cooling water as a common refrigerant | coolant used for the cooperative cooling system of a fuel cell and an air conditioning, fluid refrigerants other than cooling water may be sufficient. In addition, although the cooling system on the fuel cell stack side performs cooperative cooling with respect to the air compressor (ACP), a configuration that does not include cooperative cooling with respect to the ACP may be employed. In addition, the AC heat exchanger that exchanges heat between the common refrigerant and the air conditioning heat pump and the heat core will be described as being arranged in the cooling system on the air conditioning side. It can also be set as the structure included in. For example, an auxiliary heater or the like may be included in the air conditioning side cooling system. In some cases, the AC heat exchanger may be omitted.

  Since the fuel cell and air conditioning cooperative cooling system is a cooling system applied to the fuel cell operating system, the configuration of the fuel cell operating system will be described first, and then the fuel cell and air conditioning cooperative cooling system will be installed. State.

  FIG. 1 is a configuration diagram of a fuel cell operation system 10 to which a cooperative cooling system of a fuel cell and air conditioning is applied. The fuel cell operation system 10 includes an operation system main body 20 and a control unit 70 that controls each element of the operation system main body 20 as the entire system.

  The operation system main body 20 includes a fuel cell main body called a fuel cell stack 22 in which a plurality of fuel cells are stacked, elements for supplying hydrogen gas arranged on the anode side of the fuel cell stack 22, and a cathode side. It is comprised including each element for the air supply arrange | positioned.

  The fuel cell stack 22 is formed by laminating a plurality of unit cells in which separators are arranged and sandwiched on both outer sides of an MEA (Membrane Electrode Assembly) in which catalyst electrode layers are arranged on both sides of an electrolyte membrane. The fuel cell stack 22 has a function of supplying a fuel gas such as hydrogen to the anode side, supplying an oxidizing gas containing oxygen, for example, air, to the cathode side, generating power by a cell chemical reaction through the electrolyte membrane, and taking out necessary power. Have The generated power is detected by the FC generated power detection unit 68, and the data of the detected generated power is transmitted to the control unit 70.

  The anode-side hydrogen gas source 24 is a tank that supplies hydrogen as a fuel gas. The regulator 26 connected to the hydrogen gas source 24 has a function of adjusting the gas from the hydrogen gas source 24 to an appropriate pressure and flow rate. A pressure gauge 28 provided at the output port of the regulator 26 is a measuring instrument that detects the supply hydrogen pressure. The output port of the regulator 26 is connected to the anode side inlet of the fuel cell stack 22, and the fuel gas adjusted to an appropriate pressure and flow rate is supplied to the fuel cell stack 22.

  The flow divider 32 connected to the anode side outlet of the fuel cell stack 22 is for flowing the impurity gas concentration of the exhaust gas from the anode side outlet to the diluter 64 through the exhaust valve 34. The exhaust gas at this time is a hydrogen gas containing reaction product water in addition to nitrogen. The circulation booster 30 provided between the shunt 32 and the anode side inlet further has a function of increasing the hydrogen partial pressure of the gas returning from the anode side outlet and returning it to the anode side inlet for reuse. It has a hydrogen pump.

  The oxidant gas source 40 on the cathode side can actually use the atmosphere. The atmospheric air as the oxidizing gas source 40 is supplied to the cathode side through the filter 42. The flow meter 44 provided after the filter 42 is a flow meter that detects the total supply flow rate from the oxidizing gas source 40. The oxidizing gas thermometer 46 provided after the filter 42 has a function of detecting the temperature of the gas from the oxidizing gas source 40.

  The air compressor (ACP) 48 is a gas booster that compresses the volume of oxidizing gas by the motor 50 to increase its pressure. In addition, the ACP 48 has a function of providing a predetermined amount of oxidizing gas by changing the rotation speed (the number of rotations per minute) under the control of the control unit 70. That is, when the required flow rate of the oxidizing gas is large, the rotational speed of the motor 50 is increased. Conversely, when the required flow rate of the oxidizing gas is small, the rotational speed of the motor 50 is decreased. The ACP power consumption detection unit 52 is a measuring instrument having a function of detecting the power consumption of the ACP 48, specifically, the power consumption of the motor 50. The motor 50 increases power consumption when the rotation speed is increased, and decreases power consumption when the rotation speed is decreased. Therefore, the power consumption is closely related to the motor rotation speed or the oxidizing gas flow rate.

  The humidifier 54 has a function of appropriately humidifying the oxidizing gas and efficiently performing the fuel cell reaction in the fuel cell stack 22. The oxidizing gas appropriately moistened by the humidifier 54 is supplied to the cathode side inlet of the fuel cell stack 22 and exhausted from the cathode side outlet. At this time, water as a reaction product is also discharged together with the exhaust. Since the fuel cell stack 22 is heated to a high temperature by the reaction, the discharged water is water vapor, and this water vapor is supplied to the humidifier 54 to appropriately wet the oxidizing gas. As described above, the humidifier 54 has a function of appropriately giving water vapor to the oxidizing gas, and a gas exchanger using a so-called hollow fiber can be used.

  Here, the flow path connecting the oxidizing gas source 40 and the cathode side inlet of the fuel cell stack 22 can be referred to as an inlet side flow path. Correspondingly, the flow path connected from the cathode side outlet of the fuel cell stack 22 to the exhaust side can be called an outlet side flow path. The oxidizing gas path 66 that is an oxidizing gas path enters the fuel cell stack 22 from the inlet side channel through the humidifier 54 from the oxidizing gas source 40, and passes through the humidifier 54 from the outlet side channel. Extends to the open air.

  The pressure gauge 56 provided at the cathode side outlet of the outlet side channel has a function of detecting the gas pressure at the cathode side outlet. The pressure regulating valve 60 provided in the outlet side flow path is also referred to as a back pressure valve, and is a valve having a function of adjusting the gas pressure at the cathode side outlet and adjusting the flow rate of the oxidizing gas to the fuel cell stack 22. A valve that can adjust the effective opening of the flow path, such as a valve, can be used. Since the output port of the pressure regulating valve 60 is connected to the humidifier 54 described above, the gas that has exited the pressure regulating valve 60 supplies water vapor to the humidifier 54 and then returns to enter the diluter 64 and then to the outside. Discharged.

  The diluter 64 collects the waste water containing hydrogen from the exhaust valve 34 on the anode side and the exhaust gas containing hydrogen leaking through the MEA due to the water vapor on the cathode side, and discharges it to the outside as an appropriate hydrogen concentration. It is a buffer container.

  The control unit 70 controls the above-described elements of the operation system main body unit 20 as a whole system, and is sometimes called a so-called fuel cell CPU. For example, the control unit 70 has a function of controlling the rotational speed of the ACP 48 and controlling the pressure regulating valve 60 based on the required power generation amount and the generated power data transmitted from the FC generated power detection unit 68. Have. In addition, the control part 70 can have the function of the cooperation cooling control part 150 mentioned later. These functions can be realized by software, specifically, by executing a corresponding fuel cell operation program or the like. Some of these functions can also be realized by hardware.

  In such a fuel cell operation system 10, the fuel cell stack 22 generates heat due to a reaction between the fuel gas and the oxidizing gas. The ACP 48 also generates heat from the motor 50 and the like during its operation. Furthermore, it is preferable that the temperature of the oxidizing gas supplied to the cathode side of the fuel cell stack 22 is appropriate.

  In addition, when the fuel cell operation system 10 is mounted on a vehicle, an air conditioning system is provided for air conditioning in the vehicle interior, but waste heat from the fuel cell stack 22 is used, for example, when the vehicle interior is cold. If possible, it is desirable to use it to bring the interior of the vehicle to an appropriate temperature in a short time. On the other hand, if the low-temperature fuel cell stack 22 can be warmed up using elements of the air conditioning system at the time of starting the fuel cell stack 22, the fuel cell stack 22 can be operated at an early stage.

  As described above, the operation of the fuel cell and the air conditioning operation as a whole are performed by cooperatively controlling the cooling and the like between the elements constituting the fuel cell operation system 10 and the elements constituting the air conditioning system. It can be efficient. For this purpose, a cooperative cooling system for fuel cells and air conditioning is provided.

  In the following description, a cooling flow path for cooling the fuel cell stack with a radiator will be referred to as a main cooling flow path, and a cooling flow path for diverting refrigerant in parallel to the main cooling flow path will be described as a diversion cooling flow path. The refrigerant flowing through the main cooling flow path and the shunt cooling flow path is mainly composed of water. Then, the heat exchanger provided in the shunt cooling flow path will be described for cooling the ACP 48 and used for vehicle interior air conditioning.

  For the cooling of the ACP 48, the radiator is regarded as the first heat exchanger and is referred to as the second heat exchanger. In this case, the second heat exchanger is configured to be integrated as a cooling system by exchanging heat with an intercooler for independently cooling the conventional ACP 48 using the diverted refrigerant. The intercooler may be maintained as an independent cooling system as before, and the second heat exchanger may be used for cooling other elements.

  What is used for vehicle interior air conditioning is heat exchange between the heat of the divided refrigerant and the air blown from the blower, and heat exchange between the refrigerant gas of the air conditioning system and the refrigerant of the diverted cooling flow path. These are distinguished from each other, and the former will be referred to as a heat core and the latter as an AC heat exchanger. AC is an acronym for Air Conditioner and refers to an air conditioning system.

  The air conditioning system uses a so-called heat pump that performs cooling and heating by performing a cycle of compression and expansion of refrigerant gas. For example, when cooling is performed, the refrigerant gas is compressed by a compressor, heated to an air heat exchange with an outdoor heat exchanger, cooled with an expansion valve, cooled with an indoor heat exchanger to exchange air with the air, and the cold air is brought indoors. Send it in. When heating is performed, conversely, the refrigerant gas, which has been compressed and heated, is heat-exchanged with blown air by an indoor heat exchanger, and warm air is sent into the room. In the following description, it is assumed that a heat pump is used for cooling, and the indoor heat exchanger exchanges heat with air and sends cold air into the passenger compartment. And the AC heat exchanger is arrange | positioned in series with an outdoor heat exchanger, and the structure which flows the refrigerant gas which raised temperature into an AC heat exchanger is taken. As described above, an indoor heat exchanger and an outdoor heat exchanger are used in a heat pump type air conditioning system, which exchanges heat with cooling water that is a refrigerant used in the main cooling flow path or the diverted cooling flow path. Not what you want. The AC heat exchanger exchanges heat with the refrigerant gas of the air conditioning system and the cooling water that is the refrigerant used in the shunt cooling flow path, and is provided separately from the indoor heat exchanger and the outdoor heat exchanger.

  FIG. 2 is a diagram illustrating a configuration of a cooperative cooling system 80 for fuel cells and air conditioning. The fuel cell and air conditioning cooperative cooling system 80 includes a cooperative cooling system main body 82 and a cooperative cooling control unit 150. Here, FIG. 2 shows elements for cooperative cooling extracted from the fuel cell system for a vehicle. The fuel cell operation system 10 described in FIG. 1 and the cooperative cooling system for this fuel cell and air conditioning are shown in FIG. Together, they constitute one vehicle fuel cell system. Therefore, the cooperative cooling system main body 82 in FIG. 2 constitutes the system main body in the vehicle fuel cell system together with the operation system main body 20 in FIG. Further, as described above, the cooperative cooling control unit 150 can be configured as a part of the control unit 70 described in FIG.

  As shown in FIG. 2, the cooperative cooling system main body 82 includes a cooling system on the cathode side in the fuel cell operation system 10 and an air conditioning system 130. Of course, depending on the case, a cooling system on the anode side may be included. In addition, although it does not comprise the cooperative cooling system main-body part 82, the vehicle interior 8 is shown by FIG. 2 as an object to which the air-conditioned air is supplied.

  In FIG. 2, the fuel cell stack 22 is shown as elements of the fuel cell operating system 10, and the ACP 48, the motor 50, the humidifier 54, and the oxidizing gas path 66 are shown as elements on the cathode side. The oxidizing gas path 66 is indicated by a thin line, whereas the flow path through which the refrigerant flows is indicated by a thick line.

  The flow path through which the refrigerant flows is roughly divided into a fuel cell side circulation path for circulating the refrigerant between the fuel cell stack 22 and the radiator 100, and an air conditioning side for circulating the refrigerant for air conditioning in relation to the air conditioning system 130. It can be divided into a circulation channel. Here, the two are distinguished, and the former is called an FC circulation flow path and the latter is called an AC circulation flow path. FC is an acronym for Fuel Cell and refers to a fuel cell system. In the cooperative cooling, the FC circulation flow path and the AC circulation flow path are blocked or connected in accordance with the operation status of the fuel cell stack 22, the operation status of the air conditioning system 130, and the like. When both are cut off, the refrigerant flows through each circulation channel independently of each other. Therefore, the refrigerant flowing through the FC circulation channel and the AC circulation channel are physically the same, but the temperature, the flow rate, the flow velocity, and the like may be different. Can be referred to as the FC-side refrigerant, and the refrigerant flowing through the AC circulation channel can be referred to as the AC-side refrigerant.

  From another viewpoint, the cooperative cooling system main body 82 is provided with a main cooling flow path 84 as a flow path through which the refrigerant flows, and is further arranged in parallel with the main cooling flow path 84 to separate the same refrigerant. Cooling channels 86 and 90 are provided. The diversion cooling flow path 86 is for the ACP 48, and the diversion cooling flow path 90 is for air conditioning. Here, the main cooling flow path 84 and the diversion cooling flow path 86 for the ACP 48 constitute an FC circulation flow path. The shunt cooling channel 90 for air conditioning constitutes an AC circulation channel.

  As the refrigerant, LLC (Long Life Coolant) mainly composed of water can be used. Below, in order to distinguish with the refrigerant gas of the air conditioning system 130, the refrigerant | coolant which uses LLC etc. will only be called cooling water.

  In the main cooling flow path 84, the radiator 100 including the fan 102, the heater 104 for heating, the three-way valve 106 for appropriately diverting the cooling water to the heater 104, and the cooling water as the FC-side refrigerant are circulated. FC refrigerant pump (WP1) 108 is disposed for this purpose. The cooling water flowing through the main cooling flow path 84 circulates between the radiator 100 and the fuel cell stack 22, the heat of the fuel cell stack 22 whose temperature has risen is carried away by the cooling water, cooled by the radiator 100, and again the fuel cell. It has a function of returning to the stack 22.

  An FC cooling water thermometer 112 is provided on the outlet side of the fuel cell stack 22 in the main cooling flow path 84 as FC refrigerant temperature detecting means for detecting the cooling water temperature that is the temperature of the FC side refrigerant. Detection data of the FC cooling water thermometer 112 is transmitted to the cooperative cooling control unit 150.

  The humidifier 54 is arranged in parallel to the gas inlet and the gas outlet for supplying the oxidizing gas to the cathode side of the fuel cell stack 22 as described above, but the cooling water in the main cooling flow path 84 is supplied from the humidifier 54. Do not pass. That is, the humidifier 54 is not cooled by the cooling water in the main cooling channel 84. Of course, when the humidifier 54 needs to be cooled, the main cooling channel 84 is passed through the humidifier 54, and heat is exchanged with the humidifier by the cooling water of the main cooling channel 84. Also good.

  A shunt cooling channel 86 for the ACP 48 is arranged in parallel with the main cooling channel 84. Then, the cooling water is taken in from the discharge-side flow path in which the cooling water in the main cooling flow path 84 is returned from the fuel cell stack 22 toward the radiator 100, and the cooling water in the main cooling flow path 84 is transferred from the radiator 100 to the fuel cell stack 22. The cooling water that has been diverted to the supply-side flow path that flows toward is returned. The shunt cooling flow path 86 enters the second heat exchanger 110 from the motor 50 side of the ACP 48, where the compressed oxidizing gas supplied from the ACP 48 to the humidifier 54 and the fuel cell stack 22 flows to the oxidizing gas path 66. Heat exchange is then performed and then returned to the main cooling channel 84. Therefore, the second heat exchanger 110 has a function of adjusting the temperature of the oxidizing gas. Conventionally, this function is executed by an independent cooling system called an intercooler. However, in the configuration of FIG. 2, this conventional intercooler function is shared by the cooling system from the radiator 100 to the fuel cell stack 22 and the cooling water. It has become a form to be integrated.

  Here, the FC refrigerant pump 108 is provided in the supply side flow path of the main cooling flow path 84, and is provided downstream of the cooling water return diversion position of the diversion cooling flow path 86. Referring to FIG. 2, the second heat exchanger 110 receives cooling water from the downstream side of the radiator 100 and the upstream side of the FC refrigerant pump 108. That is, the radiator 100 and the second heat exchanger 110 are provided as the coolant flows upstream of the FC refrigerant pump 108, and the fuel cell stack 22 is provided as the coolant flows downstream of the FC refrigerant pump 108.

  Therefore, in this configuration, if the shunt cooling flow path 90 for air conditioning is separated, (the amount of cooling water flowing through the radiator 100) + (the amount of cooling water flowing through the second heat exchanger 110) = the total amount of cooling water = Therefore, a considerably large amount of cooling water can be supplied to the fuel cell stack 22. As a result, when the temperature of the fuel cell stack 22 is too high, the heat can be quickly carried out to the radiator 100 side. Further, the ratio of (the amount of cooling water flowing through the radiator 100) and (the amount of cooling water flowing through the second heat exchanger 110) can also be determined by the ratio of these flow path resistances, or the control for controlling the diversion ratio. Using the valves, the amount of cooling water flowing through these can be determined, and the radiator 100 and the second heat exchanger 110 can be operated cooperatively.

  Further, since the shunt cooling flow path 86 is provided in parallel with the main cooling flow path 84, the temperature of the cooling water discharged from the second heat exchanger 110 and the temperature of the cooling water discharged from the fuel cell stack 22 are The difference can be reduced. The former defines the oxidizing gas temperature on the oxidizing gas inlet side of the humidifier 54, and the latter defines the temperature of the oxidizing gas outlet of the humidifier 54, so that the temperature difference between both ends of the gas inlet of the humidifier 54 is determined. Even when a hollow fiber structure is used, damage due to temperature differences at both ends can be suppressed.

  In the cooperative cooling system main body 82 of FIG. 2, in addition to the shunt cooling flow path 86 for the ACP 48, a shunt cooling flow path 90 for air conditioning is further provided. The shunt cooling flow path 90 for air conditioning constitutes an AC circulation flow path as described above, and includes two heat exchangers and an AC refrigerant pump that circulates the AC-side refrigerant in the path ( WP2) 126. One of the two heat exchangers is a heat core 120 and the other is an AC heat exchanger 124. And the shunt cooling flow path 90 which is AC circulation flow path is comprised from the flow path in which these two heat exchangers are arrange | positioned, and the flow path which connects the both ends of the flow path. The former is called an AC heat exchange flow path 94 and the latter is called a connection flow path 92.

Both ends of the AC heat exchange flow path 94 are connected to the connection flow path 92, and the two connection points and the FC circulation flow path are connected by the branch flow path 85 and the extension flow path 91, respectively. Is done. And the three-way valve 96 is provided in the connection point where three flow paths, the AC heat exchange flow path 94, the connection flow path 92, and the branch flow path 85 from the FC circulation flow path gather. In the example of FIG. 2, the three-way valve is not provided at the connection point where the three heat flow paths 94, the connection flow path 92, and the extension flow path 91 to the FC circulation flow path gather. In some cases, a three-way valve can also be provided here.
The operation of the three-way valve 96 will be described later.

  The heat core 120 is a pipe member that flows cooling water, which is an AC-side refrigerant, and exchanges heat between the AC-side refrigerant and the air by flowing air from the blower 122 on the outside. For example, when the AC-side refrigerant is warm, the air from the blower 122 is warmed and supplied to the vehicle interior 8 to heat the vehicle interior. Thus, the heat core 120 performs air conditioning using the heat of hot water, so to speak, it is a hot water heater.

  The AC heat exchanger 124 performs heat exchange between the refrigerant gas of the air conditioning system 130 and the cooling water that is the AC-side refrigerant. As described above, the air conditioning system 130 is a heat pump type that performs a cycle of compression and evaporation of a refrigerant gas such as carbon dioxide gas, and the indoor heat exchanger 138 The cold air is sent into the passenger compartment and the waste heat of the compressed and heated refrigerant gas is released to the outside by the outdoor heat exchanger 134. In FIG. 2, as components of the air conditioning system 130, a compressor (CP) 132 that compresses refrigerant gas, an outdoor heat exchanger 134, an expansion valve (EV) 136 that expands refrigerant gas, an indoor heat exchanger 138, outdoor heat A fan 140 is shown for releasing waste heat in the exchanger 134 to the outside air. When there is a cooling request, the refrigerant gas circulates in a circulation path connecting the compressor 132, the AC heat exchanger 124, the outdoor heat exchanger 134, the expansion valve 136, and the indoor heat exchanger 138. Since the gas refrigerant of the air conditioning system 130 and the cooling water flow inside the AC heat exchanger 124, heat exchange can be performed between the gas refrigerant and the cooling water. For example, the heat of the hot gas refrigerant can be applied to the cooling water to warm the cooling water.

  In addition to the air conditioning system 130, air conditioning using the heat core 120 and the AC heat exchanger 124 can be performed as follows. When there is a cooling request from the user or the like, the compressor 132 is driven. Then, the compressed refrigerant gas is expanded by the expansion valve 136 to lower the temperature, and is exchanged with the blown air from the blower 122 in the indoor heat exchanger 138. The heat of the blown air is taken to cool air and is sent into the vehicle interior 8. When there is a heating request from a user or the like, warm water warmed by the fuel cell stack 22 and diverted from the main cooling flow path 84 is caused to flow to the heat core 120, and air blown from the blower 122 is warmed to warm air and sent into the passenger compartment. At this time, the AC heat exchanger 124 also performs heat exchange between the hot refrigerant gas and the cooling water, and the cooling water is warmed, so that the warm air can be more effectively generated. When a user or the like requests dry air blowing, the cool air in the indoor heat exchanger 138 driven by the compressor 132 and the warm air from the heat core 120 are intermittently sent into the vehicle interior. In this way, the waste heat of the fuel cell stack 22 and the waste heat of the air conditioning system 130 are used, and cooling, heating, and dry air blowing can be performed without providing a heater that uses electric power.

  As shown in FIG. 2, the blower 122 can serve both for blowing the heat core 120 and blowing the indoor heat exchanger 138 of the air conditioning system 130. In order to avoid interference between the warm air of the heat core 120 and the cool air of the indoor heat exchanger 138, a blowing direction switching mechanism 148 that changes the direction of blowing of the blower 122 can be provided. For example, when the air blowing direction switching mechanism 148 blows air into the vehicle interior only through the heat core 120, or when air flows into the vehicle interior only through the indoor heat exchanger 138, both the heat core 120 and the indoor heat exchanger 138 are used. When the air is blown into the vehicle interior via, it can be switched between. In addition, when the air is blown without passing through the heat core 120, the air blown through the heat core 120 can be discharged outside the passenger compartment. As such a blowing direction switching mechanism 148, for example, a valve that changes the blowing passage, a moving mechanism of the blowing wall, or the like can be used.

  FIG. 3 is a diagram illustrating a detailed configuration and operation of the air blowing direction switching mechanism 148. The blowing direction switching mechanism 148 is provided with a ventilation wall moving mechanism between the heat core 120 and the indoor heat exchanger 138, and the position of the blowing wall is changed by an actuator (not shown). If necessary, a shutter mechanism 139 may be provided in front of the indoor heat exchanger 138. Control of the blowing direction switching mechanism 148 is performed by the cooperative cooling control unit 150, and details of the control procedure will be described later.

  FIG. 3A shows a case where the air blowing direction switching mechanism 148 changes the position of the air blowing wall so that the direction of air blowing is from the heat core 120 toward the indoor heat exchanger 138. Here, since the air blown from the blower 122 is warmed through the heat core 120 and the indoor heat exchanger 138 and sent to the vehicle interior 8, it can be called a heating mode. For example, when the air conditioner receives a heating request or a dry blowing request, the blowing direction of the heating mode can be used.

  FIG. 3B shows a case where the air blowing direction switching mechanism 148 changes the position of the air blowing wall so that the direction of air blowing is directed from the heat core 120 toward the vehicle interior 8. Here, since the air blown from the blower 122 is warmed through the heat core 120 and sent to the vehicle interior 8, it is still one type of heating mode, but the temperature from the heat core 120 is not used without heating by the heat pump. This is the case when sufficient heating can be achieved with only wind.

  FIG. 3C shows a case where the air blowing direction switching mechanism 148 changes the position of the air blowing wall so that the direction of air blowing is directed from the heat core 120 toward the outside 9 of the passenger compartment. Here, the heat core 120 is used as a radiator, and the heat of the heat core 120 is taken away by the air blown from the blower 122 and released to the outside 9 of the passenger compartment. For example, when the vehicle interior 8 does not need heating, and when it is desired to dissipate the heat of the cooling water from the heat core 120, the air blowing direction in the heat dissipation mode can be used.

  Returning to FIG. 2 again, the fan 140 for the outdoor heat exchanger 134 of the air conditioning system 130 can also be used as the fan 102 used in the radiator 100 for the FC circulation flow path. Alternatively, the fan 140 and the fan 102 can be arranged in the same region, and both the radiator 100 and the outdoor heat exchanger 134 can be blown. When this arrangement is adopted, the amount of blown air can be adjusted according to the operating status of the fuel cell stack 22 and the operating status of the air conditioning system 130. For example, both the fan 102 and the fan 140 are driven to maximize the amount of air flow, or one of them is driven to reduce the amount of air flow to improve fuel efficiency. Any fan can stop driving if it can.

  The three-way valve 96 is a control valve whose connection is changed under the control of the cooperative cooling control unit 150. As described above, the three-way valve 96 gathers three flow paths, one end of the AC heat exchange flow path 94, one end of the connection flow path 92, the branch flow path 85 branched from the main cooling flow path 84. Provided at the junction. The control of the connection of the three-way valve 96 is performed by switching between the following two states based on the operating status of the fuel cell stack 22, the operating status of the air conditioning system 130, and the like.

  One is a blocking state in which the main cooling channel 84 of the FC circulation channel and the shunt cooling channel 90 which is the AC circulation channel are blocked. The other is a connection state in which the connection flow path 92 of the AC circulation flow path is opened and the AC heat exchange flow path 94 is connected in parallel to the FC circulation flow path to share the FC side refrigerant and the AC side refrigerant. is there. Specifically, the flow direction of the three-way valve 96 is a blocking state when the connection channel 92 and the AC heat exchange channel 94 are connected and not connected to the branch channel 85. The AC heat exchange flow path 94 and the branch flow path 85 are connected and the connection flow path 92 is not connected is in a connected state.

  FIG. 3 shows the shut-off state, and FIG. 4 shows the connected state. In the shut-off state, the FC circulation passage through which the cooling water on the fuel cell stack 22 circulates and the AC circulation passage through which the cooling water on the air conditioning side circulates are completely cut off. The flow path is completely separated. In the FC circulation flow path, the coolant that is the FC-side refrigerant circulates between the fuel cell stack 22 and the radiator 100 by the FC refrigerant pump 108. A shunt cooling channel 86 for the ACP 48 is provided in parallel with the main cooling channel 84. In the AC circulation flow path, the connection flow path 92 and the AC heat exchange flow path 94 are connected by a three-way valve 96, and the cooling water, which is the AC-side refrigerant, passes through the heat core 120 and the AC heat exchanger 124. Circulate by 126.

  As shown in FIG. 4, in the connected state, the AC circulation channel is connected in parallel to the FC circulation channel. That is, in the main cooling flow path 84 of the FC circulation flow path, the branch flow path 85 is branched from the upstream side of the radiator 100, the downstream side of the fuel cell stack 22, and the downstream side of the FC cooling water thermometer 112. The one-way side of the AC heat exchange channel 94 and the branch channel 85 are connected by the three-way valve 96, and the connection channel 92 is separated. The other end side of the AC heat exchange flow path 94 extends and becomes an extended flow path 91 connected to the main cooling flow path 84 of the FC circulation flow path. The extension channel 91 is connected to the downstream side of the radiator 100 and the downstream side of the FC refrigerant pump 108 and the upstream side of the fuel cell stack 22 in the main cooling channel 84 of the FC circulation channel. Therefore, in the connected state, the cooling water taken from the FC circulation flow path passes through the branch flow path 85, the AC heat exchange flow path 94, and the extension flow path 91 to pass through the AC refrigerant pump 126, the heat core 120, and the AC heat exchange. While flowing through the vessel 124, it is returned to the FC circulation flow path again.

  In this connected state, (amount of refrigerant flowing through radiator 100) + (amount of refrigerant flowing through second heat exchanger 110) = total amount of refrigerant = (amount of refrigerant flowing through fuel cell stack 22) + (heat core 120, AC heat exchange) Therefore, the refrigerant can be supplied for air conditioning while supplying an appropriate amount of refrigerant to the fuel cell stack 22.

  That is, with this configuration, it is possible to supply cooling water, which is a coolant that is warmed by the operation of the fuel cell stack 22 and maintained at an appropriate temperature by the radiator 100 and circulated, for air conditioning. When the fuel cell stack 22 is not sufficiently warmed, the cold refrigerant can be prevented from being fed into the AC circulation channel on the air conditioning side by closing the three-way valve 96.

  In this way, the refrigerant is shared between the FC circulation path for the fuel cell stack 22 and the AC circulation path for the passenger compartment air conditioning, and the three-way valve is set according to the temperature of the fuel cell stack 22 and the passenger compartment temperature. By controlling the opening and closing of 96, the cooling system of the fuel cell stack 22 and the passenger compartment air conditioning system can be integrated under cooperative control.

  Returning to FIG. 2 again, the cooperative cooling control unit 150 controls the above-described elements of the cooperative cooling system main body 82 as the entire system. The cooperative cooling control unit 150 can be configured by a computer, and as described above, can be configured as one computer such as a fuel cell CPU together with the function of the control unit 70 described in FIG.

  The cooperative cooling control unit 150 functions to cooperatively control the circulation of the cooling water on the fuel cell side and the circulation of the cooling water on the air conditioning side in accordance with the operation state of the fuel cell stack 22 and the operation state of the air conditioning system 130. Have In particular, here, the cooperative cooling control unit 150 performs switching control between the shut-off state and the connected state for the three-way valve 96 that is a control valve in accordance with the operation state of the fuel cell stack 22 and the operation state of the air conditioning system 130. The shut-off / connection switching module 152 to be executed and the blowing direction switching module 154 for switching the blowing direction of the blowing direction switching mechanism 148 based on the cooling water temperature of the fuel cell stack 22 are configured. These functions can be realized by software, specifically, by executing a corresponding cooling program for the fuel cell and air conditioning. Some of these functions can also be realized by hardware.

  A function of the air blowing direction switching module 154 will be described with reference to FIG. In the following description, the reference numerals in FIGS. 1 to 5 are used. FIG. 6 is a flowchart showing a procedure for switching the blowing direction in the cooperative cooling of the fuel cell and the air conditioning. These procedures correspond to the respective processing procedures of the cooperative cooling program for the fuel cell and the air conditioning.

  As described above, the air blowing direction switching mechanism 148 has the air blowing directions of the heating mode and the heat dissipation mode. When the three-way valve 96, which is a control valve, is in the shut-off state, it is appropriate between the three heating directions of the two heating modes and the heat dissipation mode depending on the condition of the air conditioning system, that is, the cooling, heating, and dry blowing requirements. Switching can be executed so as to achieve a proper air conditioning.

  When the three-way valve 96 is in the shut-off state, FC cooling water as FC refrigerant is circulated between the fuel cell stack 22 and the radiator 100 by the FC refrigerant pump 108, and the temperature of the fuel cell stack 22 is appropriately maintained. . However, since the heat dissipation capability of the radiator 100 is limited, if the heat dissipation capability is exceeded, the temperature of the FC cooling water may deviate from the temperature suitable for the operation of the fuel cell stack 22.

Therefore, as shown in FIG. 6, it is determined whether or not the FC cooling water temperature θ _FC detected by the FC cooling water thermometer 112 exceeds a predetermined threshold water temperature θ _H (S10). The threshold water temperature θ _H is a temperature at which it is better to use the heat dissipation capacity of the heat core 120 by connecting the FC circulation path and the AC circulation path, depending on the heat dissipation capacity of the radiator 100, the discharge capacity of the FC refrigerant pump 108, and the like. Set to For example, θ _FC can be set to about 75 ° C.

  If the determination is affirmed in S10, the process proceeds to S12, and the three-way valve 96, which is a control valve, is connected (S12). As a result, the high-temperature FC cooling water is diverted to the AC circulation channel via the branch channel 85. This function is executed by the cutoff / connection switching module 152 of the cooperative cooling control unit 150.

  Then, it is determined whether or not there is a cooling request in the air conditioning system (S14). When there is a cooling request, since the air radiated by the heat core 120 cannot be sent to the vehicle interior 8, a command is sent to the air flow direction switching mechanism 148, and the air blowing direction in the heat dissipation mode that directs the air direction of the blower 122 toward the outside 9 of the vehicle interior (S16). The air blowing direction in the heat dissipation mode is the direction described with reference to FIG. As a result, the heat of the high-temperature cooling water that has been diverted from the FC circulation channel is taken away by the blower 122 in the heat core 120, dissipates heat, and the temperature decreases. The cooling water whose temperature has decreased is returned to the FC circulation channel again via the extension channel 91, and acts to lower the temperature of the cooling water flowing through the FC circulation channel as a whole. In this manner, the heat core 120 can be used as a second radiator that supplements the function of the existing radiator 100 as a radiator for the cooling water of the fuel cell stack 22.

  If it is not determined that there is a cooling request in S14, the air radiated by the heat core 120 can be sent into the vehicle interior 8, so a command is issued to the air flow direction switching mechanism 148 and the air direction of the blower 122 is directed toward the vehicle interior 8. The air blowing direction in the heating mode is set (S18). The air blowing direction in the heating mode is the direction described with reference to FIGS. As a result, the heat of the high-temperature cooling water that has been diverted from the FC circulation channel is heat-exchanged with the blower 122 in the heat core 120, and the warmed wind is sent into the vehicle interior 8. At the same time, the heat of the high-temperature cooling water that has been diverted from the FC circulation channel is taken away by the heat core 120, and the heat is dissipated to lower the temperature. The cooling water whose temperature has decreased is returned to the FC circulation channel again via the extension channel 91, and acts to lower the temperature of the cooling water flowing through the FC circulation channel as a whole. Even in this case, the heat core 120 functions as a radiator for the cooling water of the fuel cell stack 22.

  In this way, regardless of whether there is a heating request on the air conditioning side, according to the temperature of the fuel cell side refrigerant, switching from the cut-off state to the connected state, by dissipating the heat of the fuel cell side refrigerant through the heat core, The temperature of the fuel cell side refrigerant can be lowered to an appropriate range. Further, at that time, by switching the direction of the air blow after heat exchange with the heat core between the vehicle interior and the exterior of the vehicle interior, it is possible to satisfy both the requirements of the air conditioning system and the heat radiation of the cooling water.

1 is a configuration diagram of a fuel cell operation system to which a cooperative cooling system of a fuel cell and an air conditioner according to an embodiment of the present invention is applied. In embodiment which concerns on this invention, it is a figure which shows the structure of the coordinated cooling system of a fuel cell and an air conditioning. In embodiment which concerns on this invention, it is a figure explaining the structure and effect | action of a ventilation direction switching function. In embodiment which concerns on this invention, it is a figure which shows the mode of the cooperative cooling system main-body part when a three-way valve is the interruption | blocking state. In embodiment which concerns on this invention, it is a figure which shows the mode of the cooperative cooling system main-body part when a three-way valve is a connection state. In embodiment which concerns on this invention, it is a flowchart which shows the procedure of the coordinated cooling of the fuel cell and air conditioning by ventilation direction switching.

Explanation of symbols

  8 Vehicle interior, 9 Outside vehicle compartment, 10 Fuel cell operation system, 20 Operation system main body, 22 Fuel cell stack, 24 Hydrogen gas source, 26 Regulator, 28 Pressure gauge, 30 Circulation booster, 32 Shunt, 34 Exhaust valve, 40 Oxidizing gas source, 42 Filter, 44 Flow meter, 46 Oxidizing gas thermometer, 48 ACP, 50 Motor, 52 ACP power consumption detector, 54 Humidifier, 56 Pressure gauge, 60 Pressure regulating valve, 64 Diluter, 66 Oxidizing gas Path, 68 FC generated power detection section, 70 control section, 80 cooperative cooling system, 82 cooperative cooling system main body section, 84 main cooling flow path, 85 branch flow path, 86, 90 branch flow cooling flow path, 91 extension flow path, 92 Connection flow path, 94 AC heat exchange flow path, 96,106 Three-way valve, 100 Radiator, 102,140 Fan, 104 106, three-way valve, 108 FC refrigerant pump, 110 second heat exchanger, 112 FC cooling water thermometer, 120 heat core, 122 blower, 124 AC heat exchanger, 126 AC refrigerant pump, 130 air conditioning system, 132 compressor, 134 Outdoor heat exchanger, 136 expansion valve, 138 indoor heat exchanger, 148 air blowing direction switching mechanism, 149 shutter mechanism, 150 cooperative cooling control unit, 152 shut-off / connection switching module, 154 air blowing direction switching module.

Claims (3)

A cooperative cooling system that performs cooperative control by sharing a refrigerant between a fuel cell cooling system and an air conditioning cooling system,
A fuel cell side circulation passage for circulating a refrigerant between the fuel cell stack and the radiator;
An air conditioning side heat exchange channel in which a heat core for exchanging heat between the refrigerant and the air flow is disposed , and an air conditioning side circulation channel having a connection channel connecting both ends of the air conditioning side heat exchange channel;
A control valve provided between the fuel cell side circulation flow path and the air-conditioning-side circulation flow path, a cut-off state in which the fuel cell-side circulating passage and the air conditioning side circulation flow passage, the air conditioning-side circulating passage A control valve for switching between a connection state in which the fuel cell side refrigerant and the air conditioning side refrigerant are shared by opening the connection flow path and connecting the air conditioning side heat exchange flow path in parallel to the fuel cell side circulation flow path ,
A ventilation switching means for switching the direction of ventilation after heat exchange with the heat core between indoors and outdoors,
Equipped with a,
Regardless of whether there is a heating request on the air conditioning side, the control valve switches between the fuel cell side circulation channel and the air conditioning side circulation channel from the cutoff state to the connected state according to the temperature of the fuel cell side refrigerant, The heat of the fuel cell side refrigerant is dissipated through the heat core,
When the control valve switches between the fuel cell side circulation channel and the air conditioning side circulation channel from the shut-off state to the connected state, and there is a cooling request on the air conditioning side, the air blowing switching means switched, the fuel cell and the air conditioning cooperative cooling system, characterized in Rukoto heat of the fuel cell-side refrigerant is radiated to the outside air through the heat core to. The fuel cell and air conditioning cooperative cooling system according to claim 1,
When the control valve is switched from the shut-off state to the connected state between the fuel cell side circulation channel and the air conditioning side circulation channel, if there is no cooling request on the air conditioning side, the air blowing switching means the switching, the fuel cell and the air conditioning cooperative cooling system, characterized in that to dissipate the heat of the fuel cell side refrigerant into the room through the heat core. The fuel cell and air conditioning cooperative cooling system according to claim 1 ,
Control valve, and wherein the three-way valve der Rukoto provided three flow paths gather connection points of the branch flow path and said air-conditioning-side heat exchange passage the connecting flow path from the fuel cell-side circulating passage Coordinated cooling system for fuel cell and air conditioning.

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