JP4908686B2 - Temperature control device for supply gas supplied to fuel cell - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a temperature control device for a supply gas supplied to a fuel cell that appropriately controls the temperature of a humidifier in the fuel cell.
[0002]
[Prior art]
In recent years, clean and energy-efficient fuel cells have attracted attention as power sources for electric vehicles. In this fuel cell, oxygen is supplied to the cathode side and hydrogen is supplied to the anode side, and electricity is generated by the reaction of hydrogen and oxygen. In order to supply oxygen to the cathode side, air containing oxygen is supplied to the fuel cell by, for example, a compressor. At this time, in order to realize efficient power generation in the fuel cell, the air containing oxygen supplied to the fuel cell needs to be moistened to some extent. Therefore, a humidifier for humidifying air is provided between the compressor and the fuel cell.
[0003]
[Problems to be solved by the invention]
By the way, in order for the said humidifier to exhibit original humidification performance, it is necessary for air to be above a certain temperature. However, when the fuel cell is operated in a low load state, for example, when the rotation speed of the compressor is 3000 rpm or less, the amount of heat generated by the fuel cell is small, and the temperature of the exhaust air discharged from the fuel cell is also low. Therefore, the humidifier also has a problem that the temperature is likely to decrease. In addition, since the supply gas supplied from the compressor is at a high temperature, it is cooled by a radiator and then supplied to the fuel cell via a humidifier. When the fuel cell is operated in a low load state, The temperature of the radiator is also decreasing. For this reason, there is still a problem that the temperature of the humidifier tends to decrease.
[0004]
Further, since the fuel cell and the compressor are similarly cooled when the fuel cell is started, the same problem occurs.
[0005]
Therefore, the problem of the present invention is to maintain the humidifier at a constant temperature so that the humidifier can exhibit its original humidification performance even when the fuel cell is operated in a low load state. There is to do.
[0006]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention that has solved the above-described problems has a compressor that supplies a supply gas to a fuel cell, and a passage through which the supply gas flows between the compressor and the fuel cell. A humidifier for humidifying the supply gas and a radiator for cooling the supply gas provided between the compressor and the humidifier are provided in the passage and are supplied to the humidifier. The heat amount adjusting means for adjusting the heat amount of the supplied gas and the temperature of the supply gas at the inlet of the fuel cell detected by the temperature detecting means for detecting the temperature of the supply gas at the inlet of the fuel cell. by controlling the amount of heat adjusting means, and a control device for the humidifier to control the temperature of the humidifier to exert inherent humidifying performance, it is provided, wherein the heat adjusting means, the heat dissipation A flow rate adjusting valve for adjusting a flow rate ratio between the bypass passage and the passage provided between the compressor and the humidifier so as to bypass the supply gas and flow into the humidifier, or the radiator In the temperature control device for the supply gas supplied to the fuel cell, the heat dissipation amount adjustment means for controlling the heat dissipation amount of the supply gas in the fuel cell , wherein the humidifier is heated by the heat amount of the supply gas is there.
[0007]
In the invention which concerns on Claim 1, the calorie | heat amount adjustment means which adjusts the calorie | heat amount of the supply gas supplied to a humidifier from a compressor is provided. Since the temperature of the supply gas can be adjusted by adjusting the amount of heat of the supply gas by the heat amount adjusting means, a supply gas having a certain temperature or more can be supplied to the humidifier. Therefore, the humidifier can sufficiently exhibit the original humidification performance.
Further, the temperature of the supply gas at the inlet of the fuel cell is detected, and the heat amount adjusting means is controlled based on the temperature of the supply gas. For this reason, the temperature of supply gas can be adjusted so that it may become suitable temperature in order for a humidifier to exhibit original humidification performance.
In addition, since the supply air supplied from the compressor becomes high temperature due to adiabatic compression of the compressor, it is cooled by a radiator and then supplied to the humidifier. Therefore, in the invention according to claim 1, as a passage through which the supply gas supplied from the compressor to the humidifier passes, a bypass passage that bypasses the radiator is provided in addition to the passage in which the radiator is provided. During normal operation, the supply gas is cooled through the passage. When the temperature of the supply gas supplied to the humidifier is lowered, a part or all of the supply gas supplied from the compressor is passed through the bypass passage. Avoid cooling with a radiator. Thus, the supply gas heated by the compressor can be supplied to the humidifier as it is, and the humidifier can exhibit the original humidification performance.
Alternatively, in the invention according to claim 1, as the heat amount adjusting means, when the heat dissipation amount control means for controlling the heat dissipation amount of the radiator, for example, when the radiator is a water cooling type, the flow rate of the cooling water is adjusted. I have to. For this reason, in order to adjust the heat quantity which supplies supply gas to a humidifier, it is not necessary to provide a bypass passage. Therefore, it can contribute to the miniaturization of the entire apparatus.
[0008]
The invention according to claim 2, the cross-sectional area of the pre-Symbol bypass passage is a temperature control device of the feed gas supplied to the fuel cell according to claim 1, wherein the smaller than the cross-sectional area of said passageway.
The invention according to claim 3, the cross-sectional area of the bypass passage, the temperature control of the feed gas supplied to the fuel cell according to claim 2, characterized in that less than half of the cross-sectional area of the passageway Device.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a temperature control device for a supply gas supplied to a fuel cell according to an embodiment of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
First, a temperature control device (hereinafter referred to as a “temperature control device”) for supply gas supplied to the fuel cell of the first embodiment will be described.
In the drawings referred to in the first embodiment, FIG. 1 is an overall configuration diagram of a fuel cell system including the temperature control device of the first embodiment, and FIG. 2 is an explanatory diagram schematically illustrating the configuration of the fuel cell.
[0015]
A fuel cell system FCS shown in FIG. 1 is a power generation system having a fuel cell 1 including a fuel cell 1, an air supply device 2, a hydrogen supply device 3, a control device 4 and the like as a core. The temperature control device GS (GS1) includes an air supply device 2 and a control device 4. It is assumed that the fuel cell system FCS in this embodiment is mounted on a vehicle (fuel cell electric vehicle).
[0016]
As shown in FIG. 2, the fuel cell 1 is divided into a cathode electrode side (oxygen electrode side) and an anode electrode side (hydrogen electrode side) with an electrolyte membrane 1c interposed therebetween, and includes a platinum-based catalyst on each side. An electrode is provided to form a cathode electrode 1b and an anode electrode 1d. As the electrolyte membrane 1c, a solid polymer membrane, for example, a perfluorocarbon sulfonic acid membrane which is a proton exchange membrane is used. This electrolyte membrane 1c has a large number of proton exchange groups in the solid polymer, exhibits a low specific resistance of 20Ω-proton or less at room temperature when saturated with water, and functions as a proton conducting electrolyte. The catalyst included in the cathode electrode 1b is a catalyst that generates oxygen ions from oxygen, and the catalyst included in the anode electrode 1d is a catalyst that generates protons from hydrogen.
[0017]
Further, a cathode electrode side gas passage 1a through which the supply air A as an oxidant gas flows is provided in the cathode electrode 1b outside the cathode electrode 1b, and an anode electrode 1d as a fuel gas is provided outside the anode electrode 1d. An anode electrode side gas passage 1e through which the supply hydrogen H flows is provided. The inlet and outlet of the cathode electrode side gas passage 1 a are connected to the air supply device 2, and the inlet and outlet of the anode electrode side gas passage 1 e are connected to the hydrogen supply device 3. The fuel cell 1 in FIG. 2 is schematically represented as a single cell, but the actual fuel cell 1 is configured as a laminate in which about 200 single cells are stacked. . The fuel cell 1 has a cooling device (not shown) that cools the fuel cell 1 because it generates heat due to an electrochemical reaction during power generation.
[0018]
In the fuel cell 1, when supply air A is passed through the cathode electrode side gas passage 1a and supply hydrogen H is supplied to the anode electrode side gas passage 1e, hydrogen is ionized by the catalytic action at the anode electrode 1d and protonated. The generated protons move through the electrolyte membrane 1c and reach the cathode electrode 1b. The protons that reach the cathode electrode 1b immediately react with oxygen ions generated from oxygen in the supply air A in the presence of the catalyst to generate water. Supply air A containing generated water and unused oxygen is discharged from the cathode side outlet of fuel cell 1 as exhaust air Ae (exhaust air Ae contains a large amount of water). Further, when hydrogen is ionized at the anode 1d, electrons e− are generated. The generated electrons e− reach the cathode electrode 1b via an external load M such as a motor.
[0019]
Next, as shown in FIG. 1, the air supply device 2 constituting the temperature control device GS1 includes an air cleaner 21, a compressor 22, a radiator 23, a humidifier 24, a flow rate adjustment valve 25, a backflow prevention valve 26, and a pressure control. A valve 27 is provided. Among these, a radiator 23 is provided in a passage W <b> 1 between the compressor 22 and the fuel cell 1. Further, a flow rate adjustment valve 25 is provided on the downstream side of the position where the radiator 23 is disposed in the passage W1. Further, the bypass passage W <b> 2 between the compressor 22 and the fuel cell 1 is formed to bypass the radiator 23. Specifically, it branches from the passage W <b> 1 between the compressor 22 and the radiator 23 and joins the passage W <b> 1 between the flow rate adjustment valve 25 and the humidifier 24. Accordingly, the supply gas that passes through the bypass passage W <b> 2 does not pass through the radiator 23. Here, the sectional area of the bypass passage W2 is made smaller than the sectional area of the passage W1. Therefore, when the supply air A flows through the bypass passage W2, the pressure on the outlet side of the compressor 22 is higher than when the supply air A flows through the passage W1. As a result, the supply air A is heated to a higher temperature. Here, specifically, the cross-sectional area of the bypass passage W2 is desirably set to be equal to or less than half of the cross-sectional area of the passage W1. In addition, the air supply device 2 includes temperature sensors T <b> 1 and T <b> 2 that detect the temperature of the cooling water supplied to the supply air A and the radiator 23.
[0020]
The air cleaner 21 includes a filter (not shown) and the like, and filters the air (supply air A) supplied to the cathode electrode side of the fuel cell 1 to remove dust contained in the supply air A.
[0021]
The compressor 22 includes a supercharger (compressor) (not shown) and a motor that drives the supercharger. The compressor 22 adiabatically compresses supply air A used as an oxidant gas in the fuel cell 1 and pumps the compressed air to the fuel cell 1. The supply air A is heated during the adiabatic compression. The supply air A thus heated contributes to warming up of the fuel cell 1.
[0022]
The radiator 23 is provided with a cooling water passage through which cooling water flows, and the supply air supplied from the compressor 22 is cooled during normal operation of the fuel cell 1 by exchanging heat with the cooling water. . A radiator 23A is connected to the radiator 23, and the radiator 23A cools the supply air A by the radiator 23 and cools the cooling water heated by the heat by, for example, a cooling fan. The temperature of the supply air supplied from the compressor 22 during normal operation of the fuel cell 1 is normally about 120 ° C., but the fuel cell 1 is operated at a temperature of about 80 to 90 ° C. For this reason, the supply air A is cooled to about 65 to 80 ° C. and introduced into the fuel cell 1.
[0023]
The humidifier 24 is of a fuel cell exhaust gas supply type, and for example, a hollow fiber membrane bundle in which a large number, specifically, 5000 hollow fiber membranes are bundled is accommodated in the housing, and the hollow fiber membrane is provided. The supply air A passes inside, and the exhaust air Ae passes inside the housing and outside the hollow fiber membrane. In the fuel cell 1, water is generated with power generation, and the exhausted air Ae contains a large amount of moisture. Therefore, the moisture is exchanged with the supply air A to humidify the supply air A. In addition to the fuel cell exhaust gas supply type, the humidifier is composed of a venturi (not shown), a water storage tank, a siphon tube connecting the venturi and the water storage tank (a kind of carburetor), and water storage. It is possible to appropriately use a known one such as one that humidifies the supply air A by sucking and spraying the water for humidification stored in the tank by the venturi effect.
[0024]
The flow rate adjustment valve 25 is a valve capable of adjusting the opening degree of the flow path. The flow rate increases by increasing (opening) the opening degree, and the flow rate decreases by decreasing (closing) the opening degree. It is like that. Accordingly, when the flow rate adjustment valve 25 is opened, the flow rate of the supply air A flowing through the passage W1 increases, and the flow rate of the supply air A flowing through the bypass passage W2 decreases. Conversely, when the flow rate adjustment valve 25 is closed, the flow rate of the supply air A flowing through the passage W1 decreases, and the flow rate of the supply air A flowing through the bypass passage W2 increases.
[0025]
The backflow prevention valve 26 is provided in the bypass passage W <b> 2 and prevents the supply air A flowing from the compressor 22 in the direction of the humidifier 24 from backflowing.
[0026]
The pressure control valve 27 includes a butterfly valve (not shown) and a stepping motor that drives the butterfly valve. The pressure (discharge pressure) of the exhaust air Ae discharged from the fuel cell 1 is decreased / increased. Control by doing. Incidentally, when the opening degree of the pressure control valve 27 is decreased, the discharge pressure of the fuel cell 1 is increased, and the temperature rise width of the discharge air Ae is increased correspondingly. Further, when the opening degree of the pressure control valve 27 is increased, the discharge pressure of the fuel cell 1 is lowered, and the temperature rise width of the discharge air Ae is reduced correspondingly.
[0027]
The temperature sensor T <b> 1 includes a thermistor and the like, detects the temperature of the supply air A at the cathode electrode side inlet of the fuel cell 1, and transmits this detection signal to the control device 4.
[0028]
The temperature sensor T2 includes a thermistor and the like, similar to the temperature sensor T1, detects the temperature of the cooling water supplied from the radiator 23A to the radiator 23, and transmits this detection signal to the control device 4.
[0029]
As shown in FIG. 1, the hydrogen supply device 3 includes a hydrogen gas cylinder 31, a regulator 32, a hydrogen circulation pump 33, and the like.
[0030]
The hydrogen gas cylinder 31 is composed of a high-pressure hydrogen container (not shown), and stores supply hydrogen H introduced to the anode electrode side of the fuel cell 1. The supplied hydrogen H to be stored is pure hydrogen, and the pressure is 15 to 20 MPaG (150 to 200 kg / cm @ 2 G). The hydrogen gas cylinder 31 may be a hydrogen storage alloy type that stores a hydrogen at a pressure of about 1 MPaG (10 kg / cm @ 2 G) with a built-in hydrogen storage alloy.
[0031]
The regulator 32 is a pressure control valve that includes a diaphragm, a pressure adjusting spring, and the like (not shown), and reduces the supply hydrogen H stored at a high pressure to a predetermined pressure so that it can be used at a constant pressure.
[0032]
The hydrogen circulation pump 33 is composed of an ejector (not shown) or the like, and uses the flow of supplied hydrogen H toward the anode electrode side of the fuel cell 1 to supply hydrogen H after being used as fuel gas in the fuel cell 1, that is, The discharged hydrogen He discharged from the anode electrode side of the fuel cell 1 is sucked and circulated. The exhausted hydrogen is circulated because the supplied hydrogen H is pure hydrogen stored in the hydrogen gas cylinder 31.
[0033]
Next, the control device 4 includes a CPU, a memory, an input / output interface, an A / D converter, a bus, and the like (not shown), and controls the fuel cell system FCS as a whole and supplies it to the fuel cell 1. The temperature of the supply air A to be controlled is controlled. As described above, the control device 4 receives the detection signals from the temperature sensors T1 and T2. Further, the control device 4 transmits control signals for the compressor 22, the flow rate adjustment valve 25, and the pressure control valve 27. In this embodiment, the control device 4 adjusts the flow rate ratio of the supply air A flowing through the passage W1 and the bypass passage W2 by adjusting the opening degree of the flow rate adjustment valve 25 which is a calorie adjustment means, and supplies it to the humidifier 24. The amount of heat of the supplied air A is adjusted.
[0034]
Next, an example of the operation of the temperature control device GS1 at the time of low load of the fuel cell 1 according to the first embodiment will be described with reference to FIG. 3 (see FIG. 1 as appropriate).
Here, FIG. 3 is a control flow of the temperature control device of the fuel cell. The target temperature of the supply air A supplied to the fuel cell 1 is 65 ° C. to 80 ° C.
[0035]
When the temperature control of the supply air A is started, the target power generation amount of the fuel cell 1 is set based on an accelerator opening signal in a fuel cell electric vehicle (not shown), a required output from other auxiliary machines, and the like (S1). ). When the target power generation amount is set, the rotational speed of the compressor 22 corresponding to the target power generation amount is obtained and set with reference to the map shown in FIG. 4 (S2). The rotation speed of the compressor 22 here means the rotation speed of the motor that operates the compressor 22. Subsequently, it is detected whether or not the set rotation speed of the compressor 22 is less than 3000 rpm (S3). When the set rotation speed of the compressor 22 exceeds 3000 rpm, it can be determined that a certain amount of load is applied to the fuel cell 1 and normal power generation is being performed. Therefore, since it is not necessary to raise the temperature of the supply air A, the routine proceeds to the normal mode as it is (S4). That is, as shown in FIG. 4, a region where the rotation speed of the compressor 22 is 3000 rpm or less is a control region for performing temperature control according to the present embodiment.
On the other hand, when the rotation speed of the compressor 22 is 3000 rpm or less, the fuel cell 1 is in a low load state and the target power generation amount is low. When the target power generation amount of the fuel cell 1 is low, the temperature of the supply air A supplied to the humidifier 24 also decreases, and the temperature of the supply air A may deviate from the target value. Therefore, when the rotation speed of the compressor 22 is 3000 rpm or less in step S3, the temperature control of the supply air A is performed.
[0037]
In controlling the temperature of the humidifier 24, the amount of heat of the supply air that has been increased in temperature by the adiabatic compression of the compressor 22 and increased in temperature is used. More specifically, the supply air A that has been heated by the adiabatic compression of the compressor 22 includes a large amount of heat and has a high temperature. For this reason, the humidifier 24 is heated with the heat of the supply air A by supplying the supply air A that includes a large amount of heat and has a high temperature to the humidifier 24 that is at a low temperature in a low load state. To do.
[0038]
When the temperature control of the supply air A is started, first, the temperature indicated by the temperature sensor T1 is read in order to detect the temperature of the supply air A at the inlet of the fuel cell 1 by the temperature sensor T1 (S5). Supply air A is supplied from the compressor 22 to the humidifier 24. When the temperature of the supply air A is read by the temperature sensor T1, it is determined whether or not the temperature T1 is less than 65 ° C. (S6). When it is determined that the temperature T1 of the supply air A is 65 ° C. or higher, it is determined whether or not the temperature T1 of the supply air A detected by the temperature sensor T1 is 80 ° C. or lower (S7). As a result, when the temperature T1 of the supply air A is 80 ° C. or less, since the supply air A is within the target temperature range, the valve opening degree of the flow rate adjustment valve 25 is maintained (S8), and the process is terminated. . When the temperature T1 of the supply air A exceeds 80 ° C., the flow rate adjustment valve 25 is opened by 1 deg so as not to exceed the target upper limit value of the supply air A supplied to the fuel cell 1 (S9). When the flow rate adjustment valve 25 is opened, the flow rate of the supply air A flowing through the passage W1 increases and the flow rate of the supply air A flowing through the bypass passage W2 decreases. Since the supply air A flowing through the passage W1 is cooled by the radiator 23, the supply air A supplied to the humidifier 24 is cooled as a whole by increasing the flow rate of the supply air A flowing through the passage W1. Therefore, the supply air A is gradually cooled by opening the flow rate adjusting valve 25 by 1 deg.
[0039]
If it is determined in step S6 that the temperature T1 of the supply air A is 65 ° C. or less, the temperature of the supply air A supplied to the humidifier 24 is too low, so that the humidifier 24 has the original humidification performance. May not be possible. Therefore, the supply air A is supplied to the humidifier 24 at a high temperature. For this purpose, first, the temperature T2 of the cooling water in the radiator 23 is read by the temperature sensor T2 (S10). Subsequently, it is determined whether or not the coolant temperature T2 read by the temperature sensor T2 is higher than the temperature of the supply air A read by the temperature sensor T1 (S11). As a result, when the water temperature T2 of the cooling water is equal to or higher than the temperature T1 of the supply air A, the supply air A is not deprived of heat and cooled by the cooling water. Therefore, the process is finished without adjusting the opening degree of the flow rate adjusting valve 25. At this time, the supply air A passes through the passage W <b> 1 and is supplied from the compressor 22 to the humidifier 24. Accordingly, the supply air A passes through the radiator 23, but since the coolant temperature T <b> 2 in the radiator 23 is higher than the temperature T <b> 1 of the supply air A, the supply air A is not cooled by the radiator 23. Therefore, since the humidifier 24 can be heated with much heat contained in the supply air A, the original humidifying performance of the humidifier 24 can be exhibited.
[0040]
When the coolant temperature T2 is lower than the temperature T1 of the supply air A, the opening of the flow rate adjustment valve 25 is closed by 1 deg (S12). When closing the flow control valve 25, with the flow rate of the supply air A flowing through the bypass passage W2 is increased, the flow rate of the supply air A flowing through the passage W 1 is reduced. Since the bypass passage W2 is formed to bypass the radiator 23, the supply air A passing through the bypass passage W2 is supplied to the humidifier 24 without being cooled by the radiator 23. Therefore, the temperature of the supply air A supplied to the humidifier 24 gradually increases by closing the flow rate adjustment valve 25 by 1 deg and gradually increasing the flow rate of the supply air A flowing through the bypass passage W2. The humidifier 24 can be heated by the heat of A. As a result, the original humidification performance of the humidifier 24 can be exhibited.
[0041]
Then, after the adjustment of the opening degree of the flow rate adjustment valve 25 is completed, the process is finished.
[0042]
In this way, the temperature of the humidifier 24 can be controlled by adjusting the temperature of the supply air A supplied to the humidifier 24. By controlling the temperature of the humidifier 24, the original humidifying performance can be exhibited in the humidifier 24. Therefore, the fuel cell 1 can be operated in a good state.
[0043]
In this embodiment, as a condition for starting the temperature control of the supply air A, whether or not the fuel cell is in a low temperature state is determined based on the rotation speed of the compressor. The low temperature state of the fuel cell 1 can also be determined based on the temperature of the discharged air Ae.
[0044]
Further, in the start mode before the fuel cell starts normal operation, the rotation speed of the compressor 22 is normally kept low. Therefore, the humidifier 24 is warmed up in the same flow, and the hot supply air A is supplied. The humidifier 24 can be supplied. By supplying the high-temperature supply air A to the humidifier 24 in this way, the humidifier 24 can be warmed up early.
[0045]
[Second Embodiment]
Next, the temperature control apparatus of 2nd Embodiment is demonstrated. In addition, about the element, member, etc. which are the same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
Here, FIG. 5 is an overall configuration diagram of the fuel cell system including the temperature control device of the second embodiment.
[0046]
As shown in FIG. 5, the temperature control device GS2 of the second embodiment includes a flow rate adjusting valve 25 provided in the passage W1 and a backflow prevention valve 26 provided in the bypass passage W2 in the first embodiment shown in FIG. Not provided. Instead, a passage area proportional control switching valve 41 that adjusts proportionally to the respective passage areas is provided at the joining position of the passage W1 and the bypass passage W2. Other configurations are the same as those of the first embodiment. In the present embodiment, the flow rate ratio of the supply air A flowing through the passage W1 and the supply air A flowing through the bypass passage W2 can be adjusted by the opening degree of the passage area proportional control switching valve 41. Thus, by adjusting the flow rate ratio, the amount of heat of the supply air A supplied to the humidifier 24 can be adjusted.
[0047]
[Third Embodiment]
Then, the temperature control apparatus of 3rd Embodiment is demonstrated. In addition, about the element, member, etc. which are the same as 1st Embodiment and 2nd Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
Here, FIG. 6 is an overall configuration diagram of a fuel cell system including the temperature control device of the third embodiment.
[0048]
In this embodiment, compared with the first embodiment shown in FIG. 1, the bypass passage W2, the backflow prevention valve 26, and the flow rate adjustment valve 25 provided in the first embodiment are not provided. Instead, a pump 23B capable of adjusting the flow rate of the cooling water is provided between the radiator 23 and the radiator 23A. Moreover, this pump 23B is connected to the control device 4, and the flow rate of the cooling water can be controlled by the pump 23B.
[0049]
Next, the temperature control of the supply air in the present embodiment will be described with reference to FIG. 7. After setting the target power generation amount (S21), the rotation speed of the compressor is set (S22). Subsequently, it is determined whether or not the rotational speed of the compressor is 3000 rpm or less (S23), and when it exceeds 3000 rpm, the mode is shifted to the normal mode (S24). If it is 3000 rpm or less, the temperature sensor T1 is read (S25), the temperature of the supply air A is detected, and it is determined whether or not the temperature T1 of the supply air A is less than 65 ° C. (S26). The processes so far are the same as those in the first embodiment.
[0050]
When the temperature T1 of the supply air A is 65 ° C. or higher, it is determined whether or not the temperature T1 of the supply air A is 80 ° C. or lower (S27). When the temperature T1 of the supply air A is 80 ° C. or lower, the supply air A is supplied to the humidifier 24 at an appropriate temperature, so that the opening degree of the pump 23 is not adjusted and the flow rate of the cooling water remains as it is. Maintain (S28). Further, when the temperature T1 of the supply air A exceeds 80 ° C., it is necessary to reduce the amount of heat of the supply air A supplied to the humidifier 24. Therefore, the opening degree of the pump 23B is increased, and the flow rate of the cooling water supplied to the radiator 23 is gradually increased (S29). Since the cooling water cooled by the radiator 23A is supplied to the radiator 23, more heat can be taken from the supply air A supplied to the humidifier 24 by increasing the flow rate of the cooling water. . As a result, the amount of heat of the supply air A decreases and the temperature decreases. Thus, the temperature of the supply air A supplied to the humidifier 24 can be adjusted to an appropriate range.
[0051]
In addition, when the temperature T1 of the supply air A is 65 ° C. or lower in step S26, the temperature of the supply air A supplied to the humidifier 24 is too low, so it is necessary to increase the temperature by applying heat thereto. is there. Therefore, the temperature sensor T2 is read (S30), the temperature of the cooling water supplied to the radiator 23 is detected, and it is determined whether or not the water temperature T2 of the cooling water is lower than the temperature T1 of the supply air A (S31). ). As a result, when the temperature T2 of the cooling water supplied to the radiator 23 is equal to or higher than the temperature T1 of the supply air A supplied to the humidifier 24, the heat of the supply air A is not deprived by the cooling water. Therefore, the process is finished as it is. On the other hand, when the water temperature T2 of the cooling water is lower than the temperature T1 of the supply air A, the supply air A passes through the radiator 23, so that the heat is deprived by the cooling water and the temperature decreases. The operation speed of the pump 23B is decreased, and the flow rate of the cooling water is gradually decreased (S32). As the flow rate of the cooling water decreases, the amount of heat taken from the supply air A decreases, so that the temperature of the supply air A can be decreased accordingly.
Then, the process ends.
[0052]
By controlling the temperature of the supply air A in this way, the humidifying device 24 can exhibit the original humidifying performance. Therefore, the fuel cell 1 can be operated in a good state.
[0053]
The present invention is not limited to the embodiment of the invention described above, and can be widely modified.
For example, the hydrogen supply device is configured to supply hydrogen to a fuel cell from a hydrogen tank, but reforms a liquid raw fuel such as methanol with a reformer to produce a hydrogen-rich fuel gas, which is used as a fuel cell. It is good also as a structure supplied to. Further, the present invention may be applied to the hydrogen supply apparatus side regardless of whether or not the exhausted hydrogen is circulated.
[0054]
Note that the fuel cell does not consume oxygen and hydrogen unless it generates power (if electrons generated at the anode electrode do not move to the cathode electrode). By the way, if power generation is performed in the start mode, the fuel cell generates heat and contributes to the warming up of the fuel cell. (However, in the situation where the warming up is not sufficiently performed, the power generation efficiency is low and the heat generation is also low. Few). Further, the end of the start mode may be determined not by temperature but by time by providing a timer.
[0055]
【Effect of the invention】
According to the first aspect of the present invention described above, the heat amount of the supply gas is adjusted by the heat amount adjusting means for adjusting the heat amount of the supply gas supplied from the compressor to the humidifier. The temperature can be adjusted. Therefore, a supply gas having a certain temperature or higher can be supplied to the humidifier. The temperature of the humidifier can be controlled by the amount of heat of the supply gas. Therefore, the humidifier can fully exhibit the original humidification performance.
Further, the temperature of the supply gas at the inlet of the fuel cell is detected, and the heat amount adjusting means is controlled based on the temperature of the supply gas. For this reason, the temperature of supply gas can be adjusted so that it may become suitable temperature in order for a humidifier to exhibit original humidification performance.
[0056]
According to the first aspect of the present invention, when the temperature of the supply gas supplied to the humidifier is lowered, a part or all of the supply gas supplied from the compressor is passed through the bypass passage and cooled by the radiator. Do not do. Thus, the supply gas heated by the compressor can be supplied to the humidifier as it is, and the humidifier can exhibit the original humidification performance.
[0057]
According to the invention which concerns on Claim 1 , the calorie | heat amount taken from supply gas with a heat radiator with the calorie | heat amount adjustment means is adjusted. For this reason, in order to adjust the heat quantity which supplies supply gas to a humidifier, it is not necessary to provide a bypass passage. Therefore, it can contribute to the miniaturization of the entire apparatus.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a fuel cell system including a temperature control device according to a first embodiment.
FIG. 2 is an explanatory diagram schematically showing the configuration of the fuel cell of FIG. 1;
FIG. 3 is a control flow of the temperature control apparatus of the first embodiment.
4 is a graph showing the relationship between the power generation amount of the fuel cell of FIG. 2 and the rotation speed of the compressor.
FIG. 5 is an overall configuration diagram of a fuel cell system including a temperature control device of a second embodiment.
FIG. 6 is an overall configuration diagram of a fuel cell system including a temperature control device according to a third embodiment.
FIG. 7 is a control flow of the temperature control apparatus of the third embodiment.
[Explanation of symbols]
GS1 to GS3 Temperature control device FCS Fuel cell system 1 Fuel cell 2 Air supply device 3 Hydrogen supply device 4 Control device 22 Compressor 23 Radiator 23A Radiator 23B Pump (radiation amount adjustment means)
24 Humidifier 25 Flow rate adjustment valve (heat quantity adjustment means)
26 Backflow prevention valve 27 Pressure control valve W1 passage W2 Bypass passage A Supply air

Claims (3)

A compressor that supplies a supply gas to the fuel cell, and a passage through which the supply gas flows is formed between the compressor and the fuel cell; and a humidifier that humidifies the supply gas ; A radiator that is provided between the compressor and the humidifier and cools the supply gas ; and
A calorific value adjusting means for adjusting a calorific value of a supply gas supplied to the humidifier;
By controlling the calorific value adjustment means based on the temperature of the supply gas at the inlet of the fuel cell detected by the temperature detection means for detecting the temperature of the supply gas at the inlet of the fuel cell, the humidifier is originally And a control device for controlling the temperature of the humidifier so as to exhibit the humidification performance of
The heat amount adjusting means adjusts a flow rate ratio between a bypass passage and the passage provided between the compressor and the humidifier so that the supply gas flows into the humidifier bypassing the radiator. A flow rate adjusting valve, or a heat radiation amount adjusting means for controlling a heat radiation amount of the supply gas in the radiator,
The temperature control device for the supply gas supplied to the fuel cell, wherein the humidifier is heated by the amount of heat of the supply gas. The cross-sectional area of the bypass passage, the temperature control device of the feed gas supplied to the fuel cell according to claim 1, wherein the smaller than the cross-sectional area of said passageway. The apparatus for controlling the temperature of a supply gas supplied to a fuel cell according to claim 2 , wherein a cross-sectional area of the bypass passage is not more than half of a cross-sectional area of the passage.

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