JP4707948B2 - Humidification system for fuel cell - Google Patents

Description

  The present invention relates to a fuel cell humidification system used in a fuel cell automobile and the like, and more particularly, to a fuel cell humidification system including a moisture permeable humidifier.

Conventionally, a fuel cell using a solid polymer membrane as an electrolyte membrane is known. In this type of fuel cell, power is generated by electrons generated by an electrochemical reaction between supplied oxygen and hydrogen flowing through a solid electrolyte membrane. In order to efficiently generate power, it is necessary to increase the conductivity of the solid polymer film and reduce the resistance when electrons generated by the reaction move. By the way, since water is generated by the reaction in the fuel cell, the off-gas discharged after the reaction of the fuel cell contains a lot of moisture. Therefore, there has been proposed a fuel cell humidification system including a moisture permeable humidifier that uses off-gas discharged after the fuel cell reaction as a humidification gas and humidifies the reaction gas used in the fuel cell reaction.
In the fuel cell humidification system equipped with the humidifier, in order to adjust the humidification amount of the reaction gas, a bypass path that bypasses the humidifier is provided in the reaction gas supply path that reaches the fuel cell through the humidifier. The thing by which the flow volume adjustment valve which can adjust the bypass flow volume of a reactive gas was attached to the bypass path is proposed.

As a humidifying system for a fuel cell in which a humidifier is provided with a bypass, for example, due to the humidification state and the magnitude of the load current, when the solid polymer electrolyte becomes excessively dry, the output begins to gradually decrease. When the voltage characteristic falls below, there is one in which the flow rate adjustment valve of the bypass passage is operated to control the humidification amount (see Patent Document 1).
In addition, there is also a control that periodically repeats a cycle in which a humidifier is supplied for a predetermined time and then supplied to a circuit bypassing the humidifier for a predetermined time (Patent Document). 2).
Furthermore, there is also a control that determines whether or not the cell voltage, which is the voltage of each solid polymer membrane in the fuel cell, is greater than a threshold value and operates the flow rate adjustment valve (see Patent Document 3).
Japanese Patent Laid-Open No. 5-47394 JP-A-10-64569 JP 2001-216984 A

  However, in a humidifying system for a fuel cell in which a bypass path is provided in the humidifier, a water permeable membrane is formed in the moisture permeable humidifier provided in the humidifying system for the fuel cell. When the valve fails, the temperature of the water permeable membrane rises by transferring heat from the fuel cell to these water permeable membranes. As a result, if the temperature of the water permeable membrane exceeds the endurance temperature, the function of the water permeable membrane is impaired, the humidifier breaks down, and the function of the fuel cell humidification system is impaired. There is a problem of causing failure. Therefore, there has been a demand for a fuel cell humidification system having a function of preventing a humidifier failure and a fuel cell output drop or failure by detecting a failure of the flow rate adjusting valve.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a humidifying system for a fuel cell that prevents a failure of the humidifier and a decrease in output or failure of the fuel cell.

The present invention employs the following means in order to solve the above problems. That is, the heat exchange between the reaction gas and the off-gas with humidifying the fuel cell water in off-gas discharged reaction gases used in the reaction of (for example, a fuel cell 1 in the embodiment) after the reaction of the fuel cell A humidifier (for example, the humidifier 7 in the embodiment), a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier (for example, the bypass path 8 in the embodiment), and a reaction that passes through the bypass path In a humidification system for a fuel cell including a flow rate adjustment valve (for example, the flow rate adjustment valve 9 in the embodiment) provided in the bypass path for adjusting the flow rate of gas or off gas, the opening degree of the flow rate adjustment valve is controlled. The flow control valve control means to be performed (for example, the control unit 13 in the embodiment) and the temperature of at least one of the reaction gas and the off gas are set. The temperature detecting means (for example, the sensors 10, 11, 12 in the embodiment), the temperature of at least one of the reaction gas and the off-gas detected by the temperature detecting means at least downstream of the humidifier, Whether the flow rate adjustment valve is malfunctioning by comparing the temperature of at least one of the reaction gas and the off-gas when the flow rate adjustment valve control means normally controls the opening degree of the flow rate adjustment valve. It is characterized by comprising opening degree control determining means (for example, the control unit 13 in the embodiment) for determining whether or not.

  If the control of the opening of the flow control valve is not normally performed by the flow control valve control means, the flow control valve should be opened or closed even though it should be opened. However, since it is opened, the flow rate of the reaction gas or off gas passing through the bypass path is different from the flow rate that should normally be. As a result, the temperature of the reaction gas or off-gas that passes through the bypass passage is different from the temperature of the reaction gas or off-gas that does not pass through the bypass passage, so that the temperature of the reaction gas or off-gas is higher or lower than those during normal times. . Therefore, when it is detected by the temperature detection means that the temperature of the reaction gas or off-gas is different from those at normal times, the control of the opening degree of the flow rate adjustment valve is controlled by the flow rate adjustment valve control means. It is possible to detect a failure of the flow rate adjustment valve by determining that the operation is not normally performed.

The humidification system for a fuel cell according to the invention described in claim 1 humidifies the reaction gas used for the reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell, and the reaction gas and the off-gas. A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to open the flow control valve, said temperature sensing hand downstream of the humidifier Reaction gas temperature of the reaction gas is detected, passing through the temperature sensing means downstream of the humidifier when the opening control of the flow control valve by the flow rate adjusting valve control means is successful by if the temperature upper limit value or more, wherein said flow control valve has a opening control determining means for determining that a failure.

A humidification system for a fuel cell according to a second aspect of the present invention humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell, and combines the reaction gas and the off-gas. A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to close the flow control valve, said temperature sensing hand downstream of the humidifier Reaction gas temperature of the reaction gas is detected, passing through the temperature sensing means downstream of the humidifier when the opening control of the flow control valve by the flow rate adjusting valve control means is successful by If it is lower than the temperature lower limit value, wherein said flow control valve has a opening control determining means for determining that a failure.

  The off-gas discharged from the fuel cell is high in temperature due to the reaction heat of the fuel cell. This off gas is used as a humidifying gas, and the reaction gas used for the reaction of the fuel cell is humidified by the off gas. Therefore, when the flow rate adjustment valve is closed, the reaction gas downstream of the humidifier is humidified by the off gas and becomes higher than a predetermined temperature. On the other hand, if the flow regulating valve is opened, the proportion of the reaction gas that is not affected by the reaction of the fuel cell in the reaction gas downstream of the humidifier increases, so that the reaction gas downstream of the humidifier is less than the predetermined temperature. It becomes low temperature. Therefore, when the temperature of the reaction gas detected by the temperature detection means on the downstream side of the humidifier is equal to or higher than a predetermined value, even though control is performed to open the flow rate adjustment valve, the flow rate adjustment valve is closed. Therefore, it can be determined that the flow rate adjustment valve is malfunctioning. Similarly, when the temperature of the reaction gas detected by the temperature detection means on the downstream side of the humidifier is not more than a predetermined value despite the control for closing the flow rate adjustment valve, the flow rate adjustment valve is Since it is considered to be open, it can be determined that the flow rate adjustment valve has failed.

A humidifying system for a fuel cell according to a third aspect of the present invention humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell, and combines the reaction gas and the off-gas. A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to open the flow control valve, said temperature sensing hand on the upstream side of the humidifier And temperature off-gas detected by the difference between the temperature of the humidifier reaction gas detected by the temperature detecting means on the downstream side of the normal opening control of the flow control valve by the flow rate adjusting valve control means The lower temperature limit value of the difference between the temperature of the off-gas passing through the temperature detection means on the upstream side of the humidifier and the temperature of the reaction gas passing through the temperature detection means on the downstream side of the humidifier If it is less, wherein said flow control valve has a opening control determining means for determining that a failure.

According to a fourth aspect of the present invention, there is provided a fuel cell humidification system that humidifies a reaction gas used for a reaction of a fuel cell with moisture in an off gas discharged after the reaction of the fuel cell and A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to close the flow control valve, said temperature sensing hand on the upstream side of the humidifier And temperature off-gas detected by the difference between the temperature of the humidifier reaction gas detected by the temperature detecting means on the downstream side of the normal opening control of the flow control valve by the flow rate adjusting valve control means The upper temperature limit value of the difference between the temperature of the off gas passing through the temperature detection means upstream of the humidifier and the temperature of the reaction gas passing through the temperature detection means downstream of the humidifier When it is above, it has the opening degree control judgment means which judges that the said flow regulating valve is out of order, It is characterized by the above-mentioned.

  When the flow rate adjustment valve is closed, the reaction gas downstream of the humidifier is humidified by the off gas and becomes high temperature, so that the temperature difference from the off gas becomes a predetermined value or less. On the other hand, when the flow rate adjustment valve is opened, the reaction gas downstream of the humidifier becomes low temperature by increasing the proportion of the reaction gas downstream of the humidifier that is not affected by the reaction of the fuel cell. The temperature difference from the off-gas becomes a predetermined value or more. Therefore, despite the control to open the flow rate adjustment valve, the temperature of the off-gas detected by the temperature detection means upstream of the humidifier and the reaction detected by the temperature detection means downstream of the humidifier When the difference from the gas temperature is equal to or less than the predetermined value, it is considered that the flow rate adjusting valve is closed, and therefore it can be determined that the flow rate adjusting valve is malfunctioning. Similarly, despite the control for closing the flow rate adjusting valve, the temperature of the off-gas detected by the temperature detecting means upstream of the humidifier and the temperature detecting means detected downstream of the humidifier. When the difference from the temperature of the reaction gas is equal to or greater than a predetermined value, it is considered that the flow rate adjustment valve is open, so that it can be determined that the flow rate adjustment valve has failed.

A humidifying system for a fuel cell according to a fifth aspect of the present invention humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell, and combines the reaction gas and the off-gas. A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to open the flow control valve, said temperature sensing hand downstream of the humidifier And the temperature of the reaction gas detected by the difference between the temperature of the reaction gas detected by said temperature detecting means at the upstream side of the humidifier, opening control of the flow control valve by the flow rate adjusting valve control means The temperature of the difference between the temperature of the reaction gas that passes through the temperature detection means on the downstream side of the humidifier and the temperature of the reaction gas that passes through the temperature detection means on the upstream side of the humidifier in a normal operation. If it is more than the upper limit value, characterized in that the flow control valve has a opening control determining means for determining that a failure.

According to a sixth aspect of the present invention, there is provided a fuel cell humidification system that humidifies a reaction gas used for a reaction of a fuel cell with moisture in an off-gas discharged after the reaction of the fuel cell, and A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas and detecting means, when the pre-Symbol flow control valve control means is controlled so as to close the flow control valve, said temperature sensing hand downstream of the humidifier And the temperature of the reaction gas detected by the difference between the temperature of the reaction gas detected by said temperature detecting means at the upstream side of the humidifier, opening control of the flow control valve by the flow rate adjusting valve control means The temperature of the difference between the temperature of the reaction gas that passes through the temperature detection means on the downstream side of the humidifier and the temperature of the reaction gas that passes through the temperature detection means on the upstream side of the humidifier in a normal operation. If it is less than the lower limit value, characterized in that the flow control valve has a opening control determining means for determining that a failure.

  When the flow rate adjustment valve is closed, the reaction gas downstream of the humidifier is humidified by the off gas and becomes high temperature, so that the temperature difference with the reaction gas upstream of the humidifier becomes a predetermined value or more. On the other hand, when the flow rate adjustment valve is opened, the reaction gas downstream of the humidifier becomes low temperature by increasing the proportion of the reaction gas downstream of the humidifier that is not affected by the reaction of the fuel cell. The temperature difference with the reaction gas upstream of the humidifier becomes a predetermined value or less. Therefore, in spite of performing control to open the flow rate adjusting valve, the temperature of the reaction gas detected by the temperature detection means on the downstream side of the humidifier and the temperature detection means on the upstream side of the humidifier are detected. When the difference from the temperature of the reaction gas is equal to or greater than a predetermined value, it is considered that the flow rate adjustment valve is closed, and therefore it can be determined that the flow rate adjustment valve is malfunctioning. Similarly, the temperature of the reaction gas detected by the temperature detection means on the downstream side of the humidifier and the temperature detection means on the upstream side of the humidifier are detected despite the control for closing the flow rate adjusting valve. When the difference between the reaction gas temperature and the temperature is equal to or less than a predetermined value, it is considered that the flow rate adjustment valve is open, and therefore it can be determined that the flow rate adjustment valve is malfunctioning.

The humidification system for a fuel cell according to the invention described in claim 7 humidifies the reaction gas used for the reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and A humidifier that performs heat exchange, a bypass path that bypasses the humidifier and is connected to the downstream side of the humidifier, and is provided in the bypass path to adjust the flow rate of the reaction gas or off-gas that passes through the bypass path In the humidifying system for a fuel cell provided with the flow rate adjusting valve, the flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, and the temperature for detecting the temperature of at least one of the reaction gas and the off gas detecting means and, before SL when controlled to close the flow control valve controls the flow rate adjusting valve which has been opened by means or closed which was the flow When controlled so as to open the regulating valve, it is determined that the flow rate control valve when the temperature of the humidifier reaction gas detected by the temperature detecting means on the downstream side of a constant is faulty opening And a control judging means .

  When the flow regulating valve is closed, the reaction gas downstream of the humidifier is humidified by the off gas and becomes high temperature. On the other hand, when the flow rate adjustment valve is opened, the ratio of the reaction gas that is not affected by the reaction of the fuel cell in the reaction gas downstream of the humidifier increases, so the reaction gas downstream of the humidifier becomes low temperature. Therefore, when control is performed to close the flow control valve that has been opened, the reaction gas detected by the temperature detector on the downstream side of the humidifier, even though the reaction gas on the downstream side of the humidifier changes from low temperature to high temperature. When the gas temperature is constant, it is considered that the flow rate adjusting valve has not changed since the flow rate adjusting valve is opened, and therefore it can be determined that the flow rate adjusting valve has failed. Similarly, when control is performed to open the closed flow rate adjustment valve, the reaction gas on the downstream side of the humidifier was detected by the temperature detection means on the downstream side of the humidifier, despite the change from high temperature to low temperature. When the temperature of the reaction gas is constant, it is considered that the flow rate adjustment valve has not changed since the flow rate adjustment valve is closed, so that it can be determined that the flow rate adjustment valve has failed.

The fuel cell humidification system according to claim 8 , wherein the bypass path is provided in a reaction gas supply path (for example, the reaction gas supply path 4 in the embodiment) that reaches the fuel cell through the humidifier. It is characterized by being.
By bypassing the humidifier to the reaction gas supply path, it is possible to adjust the humidification amount of the reaction gas while passing the reaction gas through the bypass path.

The fuel cell humidification system according to claim 9 , wherein the bypass path is provided in an off-gas discharge path (for example, the off-gas discharge path 6 in the embodiment) discharged from the fuel cell via the humidifier. It is characterized by being.
By bypassing the humidifier to the off gas supply path, the amount of humidification of the off gas is adjusted while passing the off gas through the bypass path, and the amount of humidification of the reaction gas is adjusted by supplying the off gas supplied to the humidifier to the reaction gas. It becomes possible.

Further, the failure detection method of the fuel cell humidification system is a humidification method in which a reaction gas used for a reaction of a fuel cell (for example, the fuel cell 1 in the embodiment) is humidified by moisture in an off-gas discharged after the reaction of the fuel cell. (For example, the humidifier 7 in the embodiment), a bypass path for bypassing the humidifier (for example, the bypass path 8 in the embodiment), and a flow rate adjusting valve for adjusting the flow rate of the reaction gas passing through the bypass path (for example, implementation) In a failure detection method for a fuel cell humidification system comprising a flow rate adjustment valve 9) in the embodiment, the reaction gas determines whether or not the flow rate adjustment valve is normally opened or closed. Alternatively, it is characterized by detecting the temperature of off-gas.

  If the flow regulating valve is not normally opened or closed, it is closed regardless of whether the flow regulating valve should be opened, or opened even though it should be closed. The flow rate of the reaction gas or off gas passing through the path is different from the normal flow rate. As a result, the temperature of the reaction gas or off-gas becomes higher or lower than their normal temperature. Therefore, if it is detected that the temperature of the reaction gas or off-gas is different from those at normal times, it is determined that the flow regulating valve is not normally opened or closed, and a failure of the flow regulating valve is detected. It becomes possible.

According to the present invention, when the temperature detecting means detects that the temperature of the reaction gas or the off gas is different from those at the normal time, the opening degree control determining means controls the opening degree of the flow rate adjusting valve. Since it is possible to detect the malfunction of the flow regulating valve by judging that the regulating valve control means is not normally performed, it is possible to prevent the malfunction of the humidifier and the decrease or malfunction of the fuel cell. it can.

According to the invention described in claim 1 or 2, when the temperature of the reaction gas detected by the temperature detecting means on the downstream side of the humidifier is a predetermined value or a value exceeding the predetermined value, the flow regulating valve is Since it can be determined that there is a failure, it is possible to prevent the failure of the humidifier and the output reduction or failure of the fuel cell.

According to the invention described in claim 3 or 4 , the temperature of the off gas detected by the temperature detection means upstream of the humidifier and the temperature of the reaction gas detected by the temperature detection means downstream of the humidifier. When the difference is a predetermined value or a value exceeding the predetermined value, it can be determined that the flow rate adjustment valve has failed, thus preventing a humidifier failure and a fuel cell output drop or failure in advance. be able to.

According to the invention described in claim 5 or 6 , the temperature of the reaction gas detected by the temperature detection means on the downstream side of the humidifier, and the temperature of the reaction gas detected by the temperature detection means on the upstream side of the humidifier Because the difference between the two is a predetermined value or a value exceeding the predetermined value, it can be determined that the flow rate adjustment valve has failed, thus preventing a humidifier failure and a fuel cell output drop or failure in advance. can do.

According to the seventh aspect of the present invention, when the temperature of the reaction gas detected by the temperature detecting means is constant on the downstream side of the humidifier, it can be determined that the flow rate adjusting valve has failed. Therefore, it is possible to prevent the failure of the humidifier and the output reduction or failure of the fuel cell.

According to the invention described in claim 8 or 9 , since it becomes possible to adjust the humidification amount of the reaction gas while allowing the reaction gas to pass through the bypass path, the humidification control of the fuel cell humidification system can be performed directly and quickly. Can be done.

According to the failure detection method of the fuel cell humidification system, if it is detected that the temperature of the reaction gas or off-gas is different from those during normal operation, it is determined that the flow control valve is not normally opened or closed. As a result, it is possible to detect a failure of the flow regulating valve, so that it is possible to prevent a failure of the humidifier and a decrease or failure of the output of the fuel cell.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a fuel cell humidification system to which the present invention is applied.
This fuel cell humidification system is used, for example, in a fuel cell vehicle. In the figure, reference numeral 1 denotes a fuel cell. The fuel cell 1 includes a large number of solid polymer membranes, and constitutes an anode electrode and a cathode electrode. Each solid polymer membrane functions as a conductive electrolyte due to proton exchange groups present in the molecule by saturation and hydration while isolating oxygen and hydrogen. And the humidifier mentioned later is used in order to humidify a solid polymer film and to improve electroconductivity.

  The gas inlets 2 and 2a of the fuel cell 1 are each supplied with a reaction gas used for the reaction of the fuel cell, specifically, air supplied from the air supply system 3 or hydrogen gas supplied from the hydrogen supply system 3a. The reaction gas supply paths 4 and 4a are connected. The reaction gas supply path 4 extends from the air supply system 3 through the humidifier 7 to the gas inlet 2 of the fuel cell 1. The reaction gas supply path 4a extends from the hydrogen supply system 3a to the gas inlet 2a of the fuel cell 1.

The gas outlets 5 and 5 a of the fuel cell 1 are connected to off-gas discharge paths 6 and 6 a for off-gas discharged from the fuel cell 1 after the reaction is completed. A humidifier 7 is provided as a moisture permeable cathode humidifier across the reaction gas supply path 4 and the offgas discharge path 6 to humidify the reaction gas air with moisture in the offgas.
The reaction gas supply path 4 is provided with a bypass path 8 that bypasses the humidifier 7. The bypass path 8 is provided with a flow rate adjusting valve 9 that adjusts the flow rate of air passing through the bypass path 8.

  A sensor 10 as a temperature detecting means for detecting the temperature of air supplied to the fuel cell 1 is provided on the upstream side of the fuel cell 1 and on the downstream side of the bypass passage 8, and the fuel cell 1 is provided on the downstream side of the fuel cell 1. A sensor 11 is provided as temperature detecting means for detecting the temperature of the air discharged from the air. Further, a sensor 12 is provided on the upstream side of the bypass path 8 as temperature detecting means for detecting the temperature of the air supplied from the air supply system 3 to the humidifier 7 or the bypass path 8.

This fuel cell humidification system is provided with a control unit 13 as a flow rate adjusting valve control means for controlling the flow rate adjusting valve 9. The control unit 13 inputs a signal related to the temperature detected by the sensors 10, 11, and 12 as temperature detecting means, and outputs a signal for driving the air supply system 3, the hydrogen supply system 3 a, and the flow rate adjustment valve 9. It is like that.
Further, the control unit 13 determines whether or not the control of the opening degree of the flow rate adjusting valve 9 is normally performed based on the temperature of the reaction gas or off gas detected by the sensors 10, 11, and 12. It has a function as an opening degree control determination means.

  A method of detecting a failure of the fuel cell humidification system in the fuel cell humidification system having the above configuration will be described with reference to a flowchart. In addition, the method of detecting the failure of the humidification system for fuel cells is the following (1) to (4), and those flowcharts are shown in FIGS. FIG. 6 is a graph showing the reaction gas temperature and off-gas temperature when the flow rate adjusting valve 9 is closed, and FIG. 7 is a graph showing the reaction gas temperature and off-gas temperature when the flow rate adjusting valve 9 is opened. It is a graph which shows temperature.

(1) Method for Detecting Failure of Fuel Cell Humidification System from Reaction Gas Temperature Detected by Sensor 10 First, the controller 13 recognizes the upper temperature limit value and the lower temperature limit value of the reaction gas passing through the sensor 10 in advance. (Step S1).
After driving the air supply system 3 and the hydrogen supply system, the control unit 13 selects whether to open or close the flow rate adjusting valve 9 (step S2).

When the control unit 13 selects to open the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas, and the control unit 13 recognizes the temperature of the reaction gas detected by the sensor 10 (step S3). Then, the detected temperature of the reaction gas is compared with the temperature upper limit value recognized in advance (step S4).
If the detected temperature of the reaction gas is equal to or higher than the temperature upper limit value, it is determined that the flow rate adjusting valve 9 has failed (step S5). On the other hand, if the detected temperature of the reaction gas is not equal to or higher than the temperature upper limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S2.

When the control unit 13 selects to close the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas, and the control unit 13 recognizes the temperature of the reaction gas detected by the sensor 10 (step S6). Then, the detected temperature of the reaction gas is compared with the temperature lower limit value recognized in advance (step S7).
If the detected temperature of the reaction gas is equal to or lower than the temperature lower limit value, it is determined that the flow rate adjustment valve 9 has failed (step S5). On the other hand, if the detected temperature of the reaction gas is not lower than the temperature lower limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S2.

  Here, when control of the opening degree of the flow rate adjusting valve 9 is not normally performed by the control unit 13, the flow rate adjusting valve 9 should be opened or should be closed even though it should be opened. In spite of being, it is in a state to be opened. Therefore, in this state, the flow rate of the reaction gas or off gas passing through the bypass 8 is different from the flow rate that should normally be. As a result, the temperature of the reaction gas or off-gas is different from the temperature of the reaction gas or off-gas that does not pass through the bypass, so that the temperature is higher or lower than those temperatures during normal operation. Therefore, when the sensor 10 detects that the temperature of the reaction gas or off-gas is different from those at the normal time, the control unit 13 controls the opening of the flow rate adjusting valve 9 normally. Therefore, it is possible to detect a failure of the flow rate adjusting valve 9.

  In this case, the off gas discharged from the fuel cell 1 is at a high temperature because it involves the reaction heat of the fuel cell 1. This off gas is used as a humidified gas, and the reaction gas used for the reaction of the fuel cell 1 is humidified by the off gas. Therefore, when the flow rate adjusting valve 9 is closed, the reaction gas downstream of the humidifier 7 is humidified by the off gas and becomes higher than a predetermined temperature. On the other hand, when the flow regulating valve 9 is opened, the proportion of the reaction gas that is not affected by the reaction of the fuel cell 1 in the reaction gas downstream of the humidifier 7 increases. The temperature is lower than a predetermined temperature. Therefore, in the case where the temperature of the reaction gas detected by the sensor 10 on the downstream side of the humidifier 7 is equal to or higher than the temperature upper limit value despite the control for opening the flow rate adjustment valve 9, the flow rate adjustment valve 9 is considered to be closed, it can be determined that the flow rate adjusting valve 9 is out of order. Similarly, the flow rate adjustment is performed when the temperature of the reaction gas detected by the sensor 10 on the downstream side of the humidifier 7 is equal to or lower than the temperature lower limit value despite the control for closing the flow rate adjustment valve 9. Since it is considered that the valve 9 is open, it can be determined that the flow rate adjusting valve 9 is out of order.

(2) Method for Detecting Failure of Humidification System for Fuel Cell from Difference between Temperature of Reactive Gas Detected by Sensor 10 and Temperature of Reactive Gas Detected by Sensor 11 First, the control unit 13 passes the sensor 10 in advance. The temperature lower limit value and the temperature upper limit value regarding the difference between the temperature of the reaction gas and the temperature of the off gas passing through the sensor 11 are recognized (step S11).
After driving the air supply system 3 and the hydrogen supply system, the control unit 13 selects whether to open or close the flow rate adjustment valve 9 (step S12).

When the control unit 13 selects to open the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas (step S13), the sensor 11 detects the off-gas temperature (step S14), and the control unit 13 Reactant gas and offgas temperatures detected by the sensor 10 and the sensor 11 are recognized. Then, the difference between the temperature of the reaction gas detected by the sensor 10 and the temperature of the off gas detected by the sensor 11 is compared with the temperature lower limit value recognized in advance (step S15).
If the detected temperature of the reaction gas is equal to or lower than the temperature lower limit value, it is determined that the flow rate adjustment valve 9 has failed (step S16). On the other hand, if the detected temperature of the reaction gas is not lower than the temperature lower limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S12.

When the control unit 13 selects to close the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas (step S17), the sensor 11 detects the off-gas temperature (step S18), and the control unit 13 Reactant gas and offgas temperatures detected by the sensor 10 and the sensor 11 are recognized. Then, the difference between the temperature of the reaction gas detected by the sensor 10 and the temperature of the off gas detected by the sensor 11 is compared with the temperature upper limit value recognized in advance (step S19).
If the detected temperature of the reaction gas is equal to or higher than the temperature upper limit value, it is determined that the flow rate adjustment valve 9 has failed (step S16). On the other hand, if the detected temperature of the reaction gas is not equal to or higher than the temperature upper limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S12.

  In this case, the off gas discharged from the fuel cell 1 is at a high temperature because it involves the reaction heat of the fuel cell 1. This off gas is used as a humidified gas, and the reaction gas used for the reaction of the fuel cell 1 is humidified by the off gas. Therefore, when the flow rate adjusting valve 9 is closed, the reaction gas downstream of the humidifier 7 is humidified by the off gas and becomes high temperature, so that the temperature difference from the off gas becomes equal to or lower than the temperature lower limit value. On the other hand, when the flow rate adjusting valve 9 is opened, the proportion of the reaction gas that is not affected by the reaction of the fuel cell 1 in the reaction gas downstream of the humidifier 7 increases, so that the reaction gas downstream of the humidifier 7 is reduced. Since the temperature is low, the temperature difference from the off gas is equal to or greater than the temperature upper limit value. Therefore, the temperature of the off-gas detected by the sensor 11 on the upstream side of the humidifier 7 and the reaction detected by the sensor 10 on the downstream side of the humidifier, despite the control for opening the flow regulating valve 9. When the difference from the gas temperature is equal to or lower than the lower temperature limit value, it is considered that the flow rate adjusting valve 9 is closed, and therefore it can be determined that the flow rate adjusting valve 9 is out of order. Similarly, the temperature of the off-gas detected by the sensor 11 on the upstream side of the humidifier 7 and the sensor 10 on the downstream side of the humidifier 7 are detected despite the control for closing the flow rate adjusting valve 9. If the difference from the temperature of the reaction gas is equal to or higher than the upper temperature limit value, it is considered that the flow rate adjusting valve 9 is open, so that it can be determined that the flow rate adjusting valve 9 is out of order.

(3) Method of Detecting Failure of Humidification System for Fuel Cell from Difference between Temperature of Reactive Gas Detected by Sensor 10 and Temperature of Reactive Gas Detected by Sensor 12 First, the control unit 13 passes through the sensor 10 in advance. The temperature upper limit value and the temperature lower limit value regarding the difference between the temperature of the reaction gas and the temperature of the reaction gas passing through the sensor 12 are recognized (step S21).
After driving the air supply system 3 and the hydrogen supply system, the control unit 13 selects whether to open or close the flow rate adjustment valve 9 (step S22).

When the control unit 13 selects to open the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas (step S23), the sensor 12 detects the temperature of the reaction gas (step S24), and the control unit 13 Recognizes the temperature of the reaction gas detected by the sensor 10 and the sensor 12, respectively. Then, the difference between the temperature of the reaction gas detected by the sensor 10 and the temperature of the reaction gas detected by the sensor 12 is compared with the temperature upper limit value recognized in advance (step S25).
If the detected temperature of the reaction gas is equal to or higher than the temperature upper limit value, it is determined that the flow rate adjustment valve 9 has failed (step S26). On the other hand, if the detected temperature of the reaction gas is not equal to or higher than the temperature upper limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S22.

When the control unit 13 selects to close the flow rate adjusting valve 9, the sensor 10 detects the temperature of the reaction gas (step S27), the sensor 12 detects the temperature of the reaction gas (step S28), and the control unit 13 Recognizes the temperature of the reaction gas detected by the sensor 10 and the sensor 12, respectively. Then, the difference between the temperature of the reaction gas detected by the sensor 10 and the temperature of the reaction gas detected by the sensor 12 is compared with a temperature lower limit value recognized in advance (step S29).
If the detected temperature of the reaction gas is equal to or lower than the temperature lower limit value, it is determined that the flow rate adjustment valve 9 has failed (step S26). On the other hand, if the detected temperature of the reaction gas is not lower than the temperature lower limit value, it is determined that the flow rate adjusting valve 9 is functioning normally, and the process returns to step S22.

  In this case, the off gas discharged from the fuel cell 1 is at a high temperature because it involves the reaction heat of the fuel cell 1. This off gas is used as a humidified gas, and the reaction gas used for the reaction of the fuel cell 1 is humidified by the off gas. Therefore, when the flow rate adjusting valve 9 is closed, the reaction gas downstream of the humidifier 7 is humidified by the off gas and becomes high temperature, so that the temperature difference with the reaction gas upstream of the humidifier 7 is equal to or higher than the temperature upper limit value. Become. On the other hand, when the flow rate adjusting valve 9 is opened, the proportion of the reaction gas that is not affected by the reaction of the fuel cell 1 in the reaction gas downstream of the humidifier 7 increases, so that the reaction gas downstream of the humidifier 7 is reduced. Since the temperature is low, the temperature difference with the reaction gas upstream of the humidifier 7 is equal to or lower than the temperature lower limit value. Therefore, the temperature of the reaction gas detected by the sensor 10 on the downstream side of the humidifier 7 and the sensor 12 on the upstream side of the humidifier 7 are detected despite the control for opening the flow rate adjusting valve 9. If the difference from the temperature of the reaction gas is equal to or higher than the upper temperature limit value, it is considered that the flow rate adjusting valve 9 is closed, and therefore it can be determined that the flow rate adjusting valve 9 is out of order. Similarly, the temperature of the reaction gas detected by the sensor 10 on the downstream side of the humidifier 7 and the sensor 12 on the upstream side of the humidifier 7 in spite of the control for closing the flow rate adjusting valve 9. When the difference between the temperature of the reaction gas and the temperature is equal to or lower than the lower temperature limit value, it is considered that the flow rate adjusting valve 9 is open, and therefore it can be determined that the flow rate adjusting valve 9 is broken. .

(4) Method for Detecting Failure of Fuel Cell Humidification System from Change in Temperature of Reactive Gas Detected by Sensor 10 The control unit 13 drives the air supply system 3 and the hydrogen supply system, and then controls the flow rate adjustment valve 9 It is selected whether to open or close (step S31).
Thereafter, when it is selected that the flow rate adjustment valve 9 is to be opened, the control unit 13 selects whether to open or close the flow rate adjustment valve 9 again (step S32). If the flow rate adjusting valve 9 is not switched, this selection is repeated until the flow rate adjusting valve 9 is switched.

When the control unit 13 selects to close the opened flow rate adjustment valve 9, the sensor 10 detects the temperature of the reaction gas before switching the flow rate adjustment valve 9 (step S33), and closes the flow rate adjustment valve 9 ( In step S34), the sensor 10 detects the temperature of the reaction gas after switching the flow rate adjusting valve 9 (step S35), and the control unit 13 recognizes the temperature of the reaction gas detected by the sensor 10, respectively. Then, the temperature of the reaction gas detected before the sensor 10 switches the flow rate adjustment valve 9 is compared with the temperature of the reaction gas detected after the sensor 10 switches the flow rate adjustment valve 9 (step S36).
If the detected temperature of the reaction gas is constant, it is determined that the flow rate adjustment valve 9 has failed (step S37). On the other hand, if the detected temperature of the reaction gas is not constant, it is determined that the flow rate adjustment valve 9 is functioning normally, and the process returns to step S31.

When the control unit 13 selects to close the flow rate adjustment valve 9 in step S31, the control unit 13 selects whether to open or close the flow rate adjustment valve 9 again (step S38). If the flow rate adjusting valve 9 is not switched, this selection is repeated until the flow rate adjusting valve 9 is switched.
When the control unit 13 selects to open the closed flow control valve 9, the sensor 10 detects the temperature of the reaction gas before switching the flow control valve 9 (step S39), and opens the flow control valve 9 ( Step S40), the sensor 10 detects the temperature of the reaction gas after switching the flow rate adjusting valve 9 (step S41), and the controller 13 recognizes the temperature of the reaction gas detected by the sensor 10, respectively. Then, the temperature of the reaction gas detected before the sensor 10 switches the flow rate adjustment valve 9 is compared with the temperature of the reaction gas detected after the sensor 10 switches the flow rate adjustment valve 9 (step S42).
If the detected temperature of the reaction gas is constant, it is determined that the flow rate adjustment valve 9 has failed (step S37). On the other hand, if the detected temperature of the reaction gas is not constant, it is determined that the flow rate adjustment valve 9 is functioning normally, and the process returns to step S31.

  In this case, the off gas discharged from the fuel cell 1 is at a high temperature because it involves the reaction heat of the fuel cell 1. This off gas is used as a humidified gas, and the reaction gas used for the reaction of the fuel cell 1 is humidified by the off gas. Therefore, when the flow regulating valve 9 is closed, the reaction gas downstream of the humidifier 7 is humidified by the off gas and becomes high temperature. On the other hand, when the flow regulating valve 9 is opened, the proportion of the reaction gas that is not affected by the reaction of the fuel cell 1 in the reaction gas downstream of the humidifier 7 increases. It becomes low temperature. Therefore, when the control for closing the opened flow rate adjusting valve 9 is performed, the reaction gas on the downstream side of the humidifier 7 is detected by the sensor 10 on the downstream side of the humidifier 7 despite the change from the low temperature to the high temperature. If the temperature of the reaction gas is constant before and after the switching of the flow regulating valve 9, it is considered that the flow regulating valve 9 is not changed from the opened state. Judgment can be made. Similarly, when control is performed to open the closed flow regulating valve 9, the reaction gas on the downstream side of the humidifier 7 is detected by the sensor 10 on the downstream side of the humidifier 7 even though the reaction gas changes from high temperature to low temperature. When the temperature of the reaction gas is constant before and after the switching of the flow regulating valve 9, the flow regulating valve 9 is broken because it is considered that the flow regulating valve 9 has not changed from the closed state. It can be judged.

According to the fuel cell humidification system having the above-described configuration, when the sensors 10, 11, and 12 detect that the temperature of the reaction gas or the off gas is different from those at the normal time, the control unit 13 adjusts the flow rate. Since it is determined that the control of the opening degree of the valve 9 is not normally performed by the control unit 13 and a failure of the flow rate adjusting valve 9 can be detected, the failure of the humidifier 7 and the output of the fuel cell 1 are detected. A drop or failure can be prevented in advance.
In addition, by humidifying the reaction gas supply path 4 with the humidifier 7 by the bypass path 8, it is possible to adjust the humidification amount of the reaction gas while passing the reaction gas through the bypass path 8. Therefore, the humidification control of the fuel cell humidification system can be performed directly and quickly.

  Note that the method of detecting a failure of the fuel cell humidification system shown in the above (1) to (4) is particularly effective in a state where the output values of the temperature sensors 10, 11, 12 and the power generation of the fuel cell 1 are stable. It is. Therefore, for example, when the temperature of each component is low, such as when the fuel cell 1 is started up, or when the output change amount of the fuel cell 1 is a predetermined value or more, the temperature of the reaction gas and off-gas is unstable. This may cause erroneous detection of temperature by the temperature sensors 10, 11, and 12. Therefore, it is preferable not to detect a failure. However, even in these cases, when the off-gas temperature is equal to or higher than a predetermined value and the temperature change of the off-gas is within a predetermined temperature range, the output values of the temperature sensors 10, 11 and 12 and the fuel cell It may be considered that power generation 1 is stable.

Next, a second embodiment of the present invention will be described with reference to the drawings.
FIG. 8 is a block diagram showing a fuel cell humidification system to which the present invention is applied.
In FIG. 8, the same components as those in FIG. 1 in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The off gas discharge path 6 is provided with a bypass path 8a that bypasses the humidifier. The bypass path 8a is provided with a flow rate adjusting valve 9a for adjusting the flow rate of air passing through the bypass path 8a.
A sensor 10 for detecting the temperature of air supplied to the fuel cell 1 is provided upstream of the fuel cell 1, and a sensor 11 for detecting the temperature of air discharged from the fuel cell 1 is provided downstream of the fuel cell 1. Is provided. A sensor 12 that detects the temperature of the air supplied from the air supply system 3 to the humidifier 7 is provided on the upstream side of the humidifier 7.

The fuel cell humidification system having the above-described configuration also uses the same method for detecting a failure in the fuel cell humidification system as in (1) to (4) in the first embodiment, and as a result, the fuel in the first embodiment. As in the case of the battery humidification system, when the sensors 10, 11, and 12 detect that the temperature of the reaction gas or off gas is different from those at the normal time, the opening of the flow rate adjusting valve 9 is controlled by the control unit 13. Therefore, it is possible to detect the failure of the flow rate adjusting valve 9 and to detect the failure of the humidifier 7 and the output reduction or failure of the fuel cell 1. Can be prevented.
Further, by bypassing the humidifier 7 to the off gas supply path 6 by the bypass path 8a, the amount of humidification of the off gas is adjusted while passing the off gas to the bypass path 8a, and the off gas supplied to the humidifier 7 is supplied to the reaction gas. Thus, it becomes possible to adjust the humidification amount of the reaction gas. Therefore, the humidification control of the fuel cell humidification system can be performed directly and quickly.

It is a block diagram of the humidification system for fuel cells concerning a 1st embodiment in the present invention. It is a flowchart of the humidification system for fuel cells which concerns on 1st Embodiment in this invention. It is a flowchart of the humidification system for fuel cells which concerns on 1st Embodiment in this invention. It is a flowchart of the humidification system for fuel cells which concerns on 1st Embodiment in this invention. It is a flowchart of the humidification system for fuel cells which concerns on 1st Embodiment in this invention. It is a graph which shows the temperature of the humidification reaction gas for fuel cells and off-gas which concern on 1st Embodiment in this invention. It is a graph which shows the temperature of the humidification reaction gas for fuel cells and off-gas which concern on 1st Embodiment in this invention. It is a block diagram of the humidification system for fuel cells which concerns on 2nd Embodiment in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell 3 Air supply system 3a Hydrogen supply system 4, 4a Reaction gas supply path 6, 6a Off-gas discharge path 7 Humidifier 8, 8a Bypass path 9, 9a Flow control valve 10, 11, 12 Sensor (temperature detection means)
13 Control unit (flow rate adjusting valve control means, opening degree control judgment means)

Claims (9)

A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow rate adjusting valve control unit is controlled to open the flow rate adjusting valve, the temperature of the reaction gas detected by the temperature detecting unit on the downstream side of the humidifier is controlled by the flow rate adjusting valve control unit. When the opening degree control of the flow rate adjusting valve is normally performed, the flow rate adjusting valve fails when it is equal to or higher than the temperature upper limit value of the reaction gas passing through the temperature detecting means on the downstream side of the humidifier. A fuel cell humidification system, comprising: an opening degree control determination unit that determines that the fuel cell is open. A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow rate adjusting valve control unit controls the flow rate adjusting valve to close, the temperature of the reaction gas detected by the temperature detecting unit on the downstream side of the humidifier is controlled by the flow rate adjusting valve control unit. When the opening control of the flow rate adjusting valve is normally performed, the flow rate adjusting valve fails when it is below the lower temperature limit value of the reaction gas passing through the temperature detecting means on the downstream side of the humidifier. A fuel cell humidification system, comprising: an opening degree control determination unit that determines that the fuel cell is open. A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow regulating valve is controlled to open the flow regulating valve, the off-gas temperature detected by the temperature detecting means upstream of the humidifier and the downstream of the humidifier The difference between the temperature of the reaction gas detected by the temperature detection means and the temperature detection on the upstream side of the humidifier when the flow rate adjustment valve control means normally controls the opening degree of the flow rate adjustment valve. When the temperature of the off-gas passing through the means and the temperature of the reaction gas passing through the temperature detecting means downstream of the humidifier is equal to or lower than the temperature lower limit value, it is determined that the flow rate adjusting valve has failed. And a fuel cell humidification system comprising: an opening degree control determination means for performing the operation. A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow control valve is controlled to close the flow control valve by the flow control valve control means, the temperature of the off-gas detected by the temperature detection means upstream of the humidifier and the downstream of the humidifier The difference between the temperature of the reaction gas detected by the temperature detection means and the temperature detection on the upstream side of the humidifier when the flow rate adjustment valve control means normally controls the opening degree of the flow rate adjustment valve. If the temperature difference between the temperature of the off-gas passing through the means and the temperature of the reaction gas passing through the temperature detection means on the downstream side of the humidifier is equal to or higher than the temperature upper limit value, it is determined that the flow regulating valve has failed. And a fuel cell humidification system comprising: an opening degree control determination means for performing the operation. A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow regulating valve is controlled to open the flow regulating valve, the temperature of the reaction gas detected by the temperature detecting means on the downstream side of the humidifier and the upstream side of the humidifier. The difference from the temperature of the reaction gas detected by the temperature detection means is that the temperature on the downstream side of the humidifier when the opening control of the flow rate adjustment valve is normally performed by the flow rate adjustment valve control unit. When the temperature of the reaction gas passing through the detection means and the temperature upper limit value of the difference between the temperature of the reaction gas passing through the temperature detection means on the upstream side of the humidifier are equal to or higher than the upper limit temperature, the flow rate adjustment valve has failed. A fuel cell humidification system comprising: an opening degree control determination means for determining A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When the flow control valve is controlled to close the flow control valve, the temperature of the reaction gas detected by the temperature detection device on the downstream side of the humidifier and the upstream side of the humidifier. The difference from the temperature of the reaction gas detected by the temperature detection means is that the temperature on the downstream side of the humidifier when the opening control of the flow rate adjustment valve is normally performed by the flow rate adjustment valve control unit. When the temperature of the reaction gas passing through the detection means is equal to or lower than the temperature lower limit value of the difference between the temperature of the reaction gas passing through the temperature detection means on the upstream side of the humidifier, the flow rate adjustment valve has failed. A fuel cell humidification system comprising: an opening degree control determination means for determining A humidifier that humidifies a reaction gas used for a reaction of the fuel cell with moisture in the off-gas discharged after the reaction of the fuel cell and performs heat exchange between the reaction gas and the off-gas, and bypasses the humidifier and In a fuel cell humidification system comprising a bypass path connected to a downstream side of a humidifier, and a flow rate adjusting valve provided in the bypass path for adjusting a flow rate of a reaction gas or an off gas passing through the bypass path,
A flow rate adjusting valve control means for controlling the opening degree of the flow rate adjusting valve, a temperature detecting means for detecting the temperature of at least one of the reaction gas and the off gas,
When controlling to close the flow regulating valve that has been opened by the flow regulating valve control means, or when controlling to open the flow regulating valve that has been closed, the downstream side of the humidifier 7. An opening degree control determining means for determining that the flow rate adjusting valve is broken when the temperature of the reaction gas detected by the temperature detecting means is constant. A humidification system for a fuel cell according to claim 1.   The fuel cell humidification system according to any one of claims 1 to 7, wherein the bypass path is provided in a reaction gas supply path that reaches the fuel cell through the humidifier. The bypass passage, humidification system for a fuel cell according to any one of claims 1 to 7, characterized in that provided in the off-gas discharge passage is discharged through the humidifier from the fuel cell.

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