JP7345388B2 - fuel cell system - Google Patents

Description

The present invention recovers water from the combustion exhaust gas obtained by burning fuel components in the anode exhaust gas discharged from the anode of the fuel cell section, and the recovered water is used for steam reforming of raw fuel in the reforming section. The present invention relates to fuel cell systems used in quality.

Patent Document 1 (Japanese Unexamined Patent Publication No. 2016-177998) describes a reforming section that steam-reforms raw fuel to generate fuel gas, a fuel cell section that has an anode and a cathode, and an anode exhaust gas discharged from the anode. A fuel cell system is described that includes a combustion section for combusting fuel components therein. This fuel cell system has a heat exchange section to which combustion exhaust gas discharged from the combustion section is supplied, and a hot water storage tank for storing hot water.The hot water taken out from the bottom of the hot water storage tank is supplied to the heat exchange section, and the By circulating the hot water that has flown through the exchange section and returning it to the upper part of the hot water storage tank, the heat exchange section is configured to recover the heat of the combustion exhaust gas in the hot water storage tank. In addition, this fuel cell system is equipped with a water tank that stores recovered water recovered from the combustion exhaust gas by cooling the combustion exhaust gas discharged from the combustion section using water stored in the hot water storage tank. The water stored in the reactor is used for steam reforming of raw fuel in the reforming section. In order to allow the fuel cell unit to continue operating without refilling the water tank, in other words, to achieve so-called water independence, the output of the fuel cell unit is controlled so that the water that can be collected in the water tank is The amount is adjusted.

JP2016-177998A

If there is no water outage, the water supply pressure is applied to the inside of the hot water storage tank via the water supply channel, so the hot water stored in the hot water storage tank is used for hot water purposes such as the kitchen and bathroom. Then, that amount of clean water is replenished into the hot water tank. However, if a water outage occurs, the water supply pressure is no longer applied inside the hot water storage tank, so even if the user opens the hot water tap, hot water will not flow from the hot water storage tank to the hot water tap, and water will not flow into the hot water storage tank. It will not be replenished. If the fuel cell section continues to operate in this condition, that is, if heat recovery from the combustion exhaust gas continues using the hot water stored in the hot water storage tank, the hot water will continue to accumulate in the hot water storage tank. As a result, low-temperature water is no longer supplied to the hot water tank. Eventually, the overall temperature of the hot water stored in the hot water storage tank will rise, and the hot water storage tank will no longer have low-temperature water that can sufficiently cool the combustion exhaust gas. As a result, the amount of water that can be recovered from the combustion exhaust gas decreases, potentially resulting in a shortage of water for steam reforming.

In this way, if the fuel cell section continues to operate while a water outage occurs, even if the output of the fuel cell section is adjusted as in the fuel cell system described in Patent Document 1, eventually, There is a possibility that there will be a shortage of water for steam reforming, making it impossible to continue operating the fuel cell section.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fuel cell system in which the operation of the fuel cell section can be continued even if a water cutoff occurs.

The characteristic configuration of the fuel cell system according to the present invention for achieving the above object includes a reforming section that steam-reforms raw fuel to generate fuel gas, and a supply of the fuel gas generated in the reforming section. a fuel cell section having an anode and a cathode to which oxygen gas is supplied, and a combustion section that burns fuel components in anode exhaust gas discharged from the anode after being used in a power generation reaction in the fuel cell section. and a heat exchange section to which combustion exhaust gas discharged from the combustion section is supplied, and a hot water storage tank for storing hot water, the hot water taken out from the lower part of the hot water storage tank is supplied to the heat exchange section, and the hot water is A heat recovery device configured to store heat of the combustion exhaust gas recovered in the heat exchange section in the hot water storage tank by circulating hot water so that the hot water flowing through the exchange section is returned to the upper part of the hot water storage tank. , a water tank for storing recovered water recovered from the combustion exhaust gas by cooling the combustion exhaust gas with the heat recovery device, and an operation control unit for controlling operation, wherein the water stored in the water tank is , a fuel cell system used for steam reforming of the raw fuel in the reforming section,
The hot water storage tank is connected to a hot water outlet that discharges hot water to the outside of the hot water storage tank, and a water supply channel that is connected to the lower part of the hot water storage tank, and the hot water inside the hot water storage tank is connected to the water supply channel through the water supply channel. When a predetermined water supply pressure is applied, water is supplied from the hot water supply channel into the hot water storage tank in response to hot water being discharged from the hot water supply channel,
comprising a water outage possibility prediction unit that predicts the occurrence and predicted time of occurrence of a water outage in which water will not be supplied from the water supply channel to the hot water storage tank in a district where the fuel cell unit is installed;
The operation control unit is configured to perform a water outage when a water outage is predicted to occur and a recovered water shortage condition indicating that the amount of recovered water in the water tank will tend to be insufficient after the predicted time of occurrence of the water outage is satisfied. Performing forced hot water discharging to discharge more than a set amount of hot water from the hot water storage tank through the hot water outlet path until the predicted occurrence time,
The operation control unit predicts that the predicted maximum temperature from the predicted time of occurrence of the water outage until after a predetermined period of time has passed is equal to or higher than the set temperature, and that the hot water is stored in the storage tank at the predicted time of occurrence of the water outage. The point is that it is determined that the recovered water shortage condition is satisfied when the predicted amount of heat storage is greater than or equal to the set amount of heat storage .

According to the characteristic configuration described above, the operation control unit performs forced hot water discharging, which discharges hot water of a set amount or more from the hot water storage tank via the hot water outlet path, until the predicted time of occurrence of water outage. Clean water is newly stored in the hot water storage tank. As a result, the amount of low-temperature hot water required to sufficiently cool the combustion exhaust gas increases in the hot water storage tank, so even if a water outage actually occurs, combustion will continue while the fuel cell unit is operating. Exhaust gas can be continuously cooled.
In a fuel cell system, as the temperature rises, the cooling performance for combustion exhaust gas decreases, and the amount of water that can be recovered from the combustion exhaust gas decreases. Furthermore, the greater the amount of heat stored in the hot water storage tank, the smaller the remaining capacity for cooling the combustion exhaust gas using the hot water stored in the hot water storage tank. Therefore, in this characteristic configuration, the operation control unit determines that the predicted maximum temperature from the predicted time of occurrence of water outage until after a predetermined period of time has passed is equal to or higher than the set temperature, and that the hot water is stored in the storage tank at the predicted time of occurrence of water outage. When the predicted amount of heat storage is greater than or equal to the set amount of heat storage, it is determined that the recovered water shortage condition is satisfied, and the forcible hot water extraction is performed. As a result, the amount of low-temperature hot water required to sufficiently cool the combustion exhaust gas increases in the hot water storage tank, so even if a water outage actually occurs, combustion will continue while the fuel cell unit is operating. Exhaust gas can be continuously cooled.
Therefore, it is possible to provide a fuel cell system in which the fuel cell section can continue to operate even if a water outage occurs.

Another characteristic configuration of the fuel cell system according to the present invention is that the operation control unit predicts that hot water in the hot water storage tank will be filled into the bathtub via the hot water outlet path until the predicted time of occurrence of water outage. In this case, the predicted amount of heat storage in the hot water storage tank at the predicted time of occurrence of water outage is predicted to be less than the set amount of heat storage.

When the hot water in the hot water storage tank is filled into the bathtub via the hot water outlet, the amount of heat stored in the hot water storage tank is significantly reduced.
Therefore, in the present characteristic configuration, if it is predicted that hot water in the hot water storage tank will be filled into the bathtub via the hot water outlet path before the predicted time of occurrence of water outage, the operation control unit may be configured to It is predicted that the predicted heat storage amount of the hot water storage tank at is less than the set heat storage amount.

Yet another feature of the fuel cell system according to the present invention is that the operation control section discharges the set amount of hot water from the hot water storage tank into the bathtub as the forced hot water discharge.

According to the above characteristic configuration, the bathtub is filled with hot water at the same time as the forced hot water discharge into the bathtub.

Still another characteristic configuration of the fuel cell system according to the present invention is that the water outage possibility prediction unit predicts the occurrence and predicted time of occurrence of the water outage based on atmospheric pressure data in the area where the fuel cell unit is installed. It is in the point of doing.

When a typhoon approaches an area where the fuel cell unit is installed, the atmospheric pressure in that area becomes lower and the rate of decrease in the atmospheric pressure value becomes faster. And it can be said that water outages are predicted to occur when a typhoon approaches.
Therefore, in this characteristic configuration, the water outage possibility predicting section can predict the occurrence and predicted time of occurrence of a water outage based on atmospheric pressure data in the area where the fuel cell section is installed.

FIG. 1 is a diagram showing the configuration of a fuel cell system. It is a flowchart explaining forced hot water tap determination processing for determining whether to perform forced hot water tap.

A fuel cell system according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing the configuration of a fuel cell system. As illustrated, the fuel cell system includes a reforming section 1, a fuel cell section FC, a combustion section 5, a heat recovery device H, a water tank 10, and an operation control section C that controls the operation. The water stored in the water tank 10 is used for steam reforming of raw fuel in the reforming section 1.

The reformer 1 steam-reforms raw fuel to generate fuel gas. In the fuel cell system shown in FIG. 1, raw fuel gas containing hydrocarbons (for example, city gas containing methane) is supplied to the reforming unit 1, and water stored in a water tank 10 is pumped to the pump 11. Powered by. The reforming section 1 then performs steam reforming of the raw fuel using combustion heat given from the combustion section 5, which will be described later. Fuel gas containing hydrogen as a main component obtained by steam reforming in the reforming section 1 is supplied to the anode 2 of the fuel cell section FC.

The fuel cell section FC includes an anode 2 to which fuel gas generated in the reforming section 1 is supplied, and a cathode 3 to which oxygen gas (air) is supplied. Specifically, the fuel cell section FC is formed by stacking a plurality of cells each having an anode 2 and a cathode 3 with an electrolyte 4 interposed between them. Electric power generated by the fuel cell unit FC is supplied to a power load device (not shown) via a power conversion unit (not shown). Note that in the anode 2, not all the supplied fuel gas is consumed in the power generation reaction, and fuel gas components such as hydrogen remain in the anode exhaust gas discharged from the anode 2.

The combustion section 5 burns the fuel gas component in the anode exhaust gas discharged from the anode 2 after being used in the power generation reaction in the fuel cell section FC. The combustion heat is then utilized in the reforming section 1. The combustion exhaust gas discharged from the combustion section 5 is supplied to the heat exchange section 6 of the heat recovery device H.

The heat recovery device H includes a heat exchange section 6 to which combustion exhaust gas discharged from the combustion section 5 is supplied, and a hot water storage tank 7 for storing hot water. The hot water storage tank 7 is connected to an exhaust heat recovery path 8 through which hot water taken out from the lower part of the hot water storage tank 7 flows while being returned to the upper part of the hot water storage tank 7. A pump 9 for flowing hot water and a heat exchange section 6 are provided in the middle of the exhaust heat recovery path 8. In other words, the heat recovery device H circulates the hot water by supplying the hot water taken out from the lower part of the hot water storage tank 7 to the heat exchange part 6 and returning the hot water that has flowed through the heat exchange part 6 to the upper part of the hot water storage tank 7. , the heat of the combustion exhaust gas recovered by the heat exchange section 6 is stored in the hot water storage tank 7. In this way, heat is stored in the hot water storage tank 7 in the form of hot water.

Since the combustion exhaust gas contains moisture, when heat is recovered from the combustion exhaust gas in the heat exchange section 6, that is, when the combustion exhaust gas is cooled, the moisture contained therein is condensed. The condensed water is collected in a water tank 10. That is, the water tank 10 plays a role of storing recovered water recovered from the combustion exhaust gas by cooling the combustion exhaust gas with the heat recovery device H. Note that a water purification section or the like may be provided to remove the electrolyte 4 and impurities that do not dissolve in water contained in the water collected in the water tank 10.

Hot water is stored in the hot water storage tank 7 in a state where temperature stratification is formed. Specifically, inside the hot water storage tank 7, relatively low temperature hot water is stored in the lower part, and relatively high temperature hot water is stored in the upper part. The temperature of the hot water stored in the hot water storage tank 7 is measured using temperature sensors T1, T2, T3, and T4. The measurement results of the temperature sensors T1 to T4 are transmitted to the operation control section C. For example, assuming that each of the temperature sensors T1, T2, T3, and T4 detects the temperature of four hot water portions stored from the top to the bottom in the hot water storage tank 7, the operation control unit C detects the temperature of each hot water portion. The current amount of heat stored in the hot water storage tank 7 can be derived based on the temperature detected by the temperature sensor and the amount of hot water detected by each temperature sensor. In this way, the relatively low-temperature hot water taken out from the lower part of the hot water storage tank 7 to the exhaust heat recovery path 8 undergoes heat exchange in the heat exchange section 6, and the combustion exhaust gas discharged from the combustion section 5 is retained. The heat is recovered (that is, the temperature of the hot water is raised), and the relatively high-temperature hot water flows into the upper part of the hot water storage tank 7.

Hot water stored in the hot water storage tank 7 can be supplied to the heat load section Lh. The heat load section Lh is a bathtub 14, a hot water supply application 15 such as a shower or a shower, and the like. The hot water storage tank 7 is connected to a hot water outlet path 12 that discharges hot water to the outside of the hot water storage tank 7 , and a water supply channel 13 that is connected to the lower part of the hot water storage tank 7 . Then, by applying a predetermined water supply pressure to the hot water inside the hot water storage tank 7 by the water supply channel 13, water is discharged from the water supply channel 13 in response to the hot water being discharged from the hot water outlet channel 12 to the heat load section Lh. The hot water is configured to be supplied into the hot water storage tank 7.

Hot water is supplied to the bathtub 14 via a solenoid valve 17 provided in the middle of the hot water outlet path 12. The opening/closing operation of this electromagnetic valve 17 is controlled by the operation control section C.

The heat load at the heat load section Lh is measured by the heat load measurement section 16, and the measurement result is transmitted to the operation control section C. For example, the heat load measuring section 16 is configured with a flow meter that measures the flow rate of hot water supplied to the heat load section Lh, and a thermometer that measures the temperature thereof. When the heat load measurement unit 16 continuously measures the heat load of the heat load section Lh, the measurement result is stored in the storage unit 25 in a form that allows the temporal change in the heat load to be understood.

The information input/output device 20 includes an output unit 21 that outputs information to a user, and an input reception unit 22 that has a plurality of switches that accept information input by the user. For example, the information input/output device 20 can be realized using a remote control device for hot water supply. The information input/output device 20 can send and receive information to and from the operation control section C. Methods for outputting information by the output unit 21 include outputting audio information and outputting image information such as characters and symbols. Further, the output section 21 and the input reception section 22 may be provided integrally using a touch panel type display device. In the illustrated example, the input receiving unit 22 includes an "on/off" switch 22a for switching execution/stop of the hot water supply function, and a "bath automatic bath" switch 22a for instructing the start of bath filling to store hot water in the bathtub 14. ” switch 22b, and a “reheating” switch 22c for instructing the start of bath reheating to heat the hot water stored in the bathtub 14 to a set temperature.

When the user turns on the "bath automatic" switch 22b, the operation control unit C opens the solenoid valve 17 and discharges the hot water stored in the hot water storage tank 7 into the bathtub 14. Fill the water with hot water. In this case, the operation control unit C may store in the storage unit 25 the time when the user turned on the “automatic bath” switch 22b.

The fuel cell system includes a water outage possibility prediction unit 26 that predicts the occurrence and predicted time of occurrence of a water outage in which water will not be supplied from the water supply channel 13 to the hot water storage tank 7 in the area where the fuel cell unit FC is installed. . For example, the water outage possibility prediction unit 26 is realized by a computer device or the like connected to the communication line 28. The information providing server device 27 collects information regarding, for example, weather, disasters, construction, events, etc., and provides the information to external devices such as the water outage possibility prediction unit 26 and the operation control unit C.

The water outage possibility prediction unit 26 receives information from the information providing server device 27. The water outage possibility predicting unit 26 predicts whether or not a water outage will occur in the area where the fuel cell unit FC is installed at a predetermined timing, such as on the hour or when information is received from the information providing server device 27. Predict the expected time of occurrence.

For example, if a typhoon is approaching the area where the fuel cell unit FC is installed, the atmospheric pressure in that area will be low and the rate of decrease in the atmospheric pressure value will be faster. And it can be said that water outages are predicted to occur when a typhoon approaches. Therefore, the water outage possibility predicting unit 26 predicts the occurrence and expected time of the water outage based on atmospheric pressure data as weather information in the area where the fuel cell unit FC is installed. In this case, the water outage possibility prediction unit 26 receives transmission of atmospheric pressure data from the information providing server device 27 that shows temporal changes in atmospheric pressure values in the area where the fuel cell unit FC is installed. Then, if the atmospheric pressure value and its rate of decrease are the same as when a typhoon is approaching, the water outage possibility prediction unit 26 determines that the area where the fuel cell unit FC is installed will be included in the storm area of a typhoon in the future. It is determined that water outage is predicted to occur. On the other hand, the water outage possibility predicting unit 26 determines that a water outage is not predicted to occur if it is predicted that the area will not be included in the stormy area of a typhoon in the future. Furthermore, what kind of information is provided from the information providing server device 27 to the water outage possibility prediction unit 26, and how the water outage possibility prediction unit 26 uses to determine that a water outage is predicted to occur? can be set as appropriate.

Then, when a water outage is predicted to occur in the area where the fuel cell unit FC is installed, the water outage possibility predicting unit 26 transmits information to that effect to the operation control unit C. In addition, the water outage possibility predicting unit 26 transmits the predicted time of occurrence of a water outage to the operation control unit C. Alternatively, the water outage possibility prediction unit 26 sends information to that effect to the operation control unit both when a water outage is predicted to occur in the area where the fuel cell unit FC is installed and when a water outage is not predicted to occur. It may be transmitted to C.

In the fuel cell system configured as described above, when there is no water outage, water supply pressure is applied to the inside of the hot water storage tank 7 via the water supply channel 13, so the water stored in the hot water storage tank 7 is When the hot water is used for filling the bathtub 14 or for hot water supply 15 for the kitchen, bathroom, etc., the hot water storage tank 7 is replenished with the same amount of clean water. However, when a water outage occurs, the water supply pressure is not applied to the inside of the hot water storage tank 7, so even if the user opens the hot water tap, hot water is not discharged from the hot water storage tank 7 to the hot water tap. Water is not being replenished. If the fuel cell unit FC continues to operate in this state, that is, if the hot water stored in the hot water storage tank 7 is used to continue recovering heat from the combustion exhaust gas, the hot water at a lower temperature will accumulate in the hot water storage tank 7. On the other hand, low-temperature tap water is not newly supplied to the hot water storage tank 7. Eventually, the overall temperature of the water stored in the hot water storage tank 7 rises, so that the hot water storage tank 7 no longer has low-temperature water that can sufficiently cool the combustion exhaust gas. As a result, the amount of water that can be recovered from the combustion exhaust gas decreases, potentially resulting in a shortage of water for steam reforming.

In this way, if the operation of the fuel cell section FC is continued during a water outage, there will eventually be a shortage of water for steam reforming, and the operation of the fuel cell section FC will not be able to continue. There is a possibility that it will disappear. Therefore, in the fuel cell system of this embodiment, the operation control unit C indicates that a water outage is predicted to occur and that the amount of recovered water in the water tank 10 will tend to be insufficient after the predicted time of occurrence of the water outage. When the recovered water shortage condition is satisfied, forced hot water is discharged from the hot water storage tank 7 via the hot water outlet path 12 until the predicted time when the water supply is interrupted.

FIG. 2 is a flowchart illustrating forced hot water tap determination processing for determining whether to perform forced hot water tap. The operation control unit C performs the control mode setting process shown in FIG. 2 at a predetermined timing, such as on the hour or when information (information indicating that a water outage is predicted to occur) is received from the water outage possibility prediction unit 26. I do.

In step #10, the operation control unit C determines whether a water outage is predicted to occur based on the information transmitted from the water outage possibility predicting unit 26. When the operation control unit C determines that a water outage is predicted to occur (“Yes” in step #10), the operation control unit C moves to step #11, and when it determines that a water outage is not predicted ( If "No" in step #10), the process moves to step #14.

In Step #11 and Step #12, the operation control unit C determines whether a recovered water shortage condition indicating that the amount of recovered water in the water tank 10 will tend to be insufficient after the predicted time of occurrence of water outage is satisfied. . For example, as the temperature rises, the performance of cooling combustion exhaust gas in the fuel cell system decreases, so it can be said that there is a high possibility that the amount of water collected in the water tank 10 tends to be insufficient. In addition, as the amount of heat stored in the hot water storage tank 7 increases, the amount of heat that can be additionally stored in the hot water storage tank 7 (thermal storage surplus) decreases. It can be said that there is a high possibility that the amount of water will tend to be insufficient. Therefore, in the present embodiment, the operation control unit C determines that the predicted maximum temperature from the predicted time of occurrence of the water outage until after a predetermined period of time has passed is equal to or higher than the set temperature ("Yes" in step #11), and when the water outage occurs. If the predicted heat storage amount predicted to be stored in the hot water storage tank 7 at the predicted time is equal to or greater than the set heat storage amount (“Yes” in step #12), it is determined that the recovered water shortage condition is satisfied.

For example, in step #11, the operation control unit C determines, based on the weather information provided from the information providing server device 27, that the predicted maximum temperature from the predicted time of occurrence of the water outage until after a predetermined period of time has passed is equal to or higher than the set temperature. Determine whether or not.

Further, in step #12, the operation control unit C determines whether there is a sufficient amount of heat (heat storage reserve) that can be additionally stored in the hot water storage tank 7 after the predicted time of occurrence of water outage. For example, the operation control unit C can derive the current amount of heat stored in the hot water storage tank 7 based on the temperatures detected by each of the temperature sensors T1, T2, T3, and T4. In addition, the operation control unit C can derive, based on the information stored in the storage unit 25, the amount of hot water that the user is expected to consume between the current time and the predicted time of the water outage. As a result, the operation control unit C can derive the predicted amount of heat storage in the hot water storage tank 7 at the predicted time of occurrence of water outage. Therefore, the operation control unit C can determine that there is little remaining heat storage capacity if the derived predicted heat storage amount is greater than or equal to the set heat storage amount, and can determine that the remaining heat storage capacity is large if the derived predicted heat storage amount is less than the set heat storage amount.

Note that there are various methods of deriving the amount of hot water that is predicted to be consumed by the user between the current time and the predicted time of occurrence of water outage, which is performed in step #12. For example, the operation control unit C determines, based on the information stored in the storage unit 25 about the time when the user turned on the “automatic bath” switch 22b in the past, between the current time and the predicted time when the water outage will occur. It is possible to predict whether the user will fill the bathtub 14 with hot water. Then, if the user fills the water with hot water, the operation control unit C predicts that the amount of hot water required for filling the water will be consumed by the user between now and the predicted time of occurrence of the water outage.
In addition, the operation control unit C predicts that the user will consume the heat between the current time and the predicted time of occurrence of the water outage, based on the past temporal changes in the load heat amount of the heat load unit Lh stored in the storage unit 25. The amount of heat generated can be predicted.

As described above, when the operation control unit C determines that the occurrence of water outage is predicted and the above-mentioned conditions for insufficient recovered water are satisfied, the operation control unit C moves to step #13. In step #13, the operation control unit C performs forced hot water discharging to discharge a set amount of hot water from the hot water storage tank 7 to the bathtub 14. For example, the operation control unit C discharges a set amount of hot water stored in the hot water storage tank 7 into the bathtub 14 by opening the solenoid valve 17 for a set period of time. As a result, the hot water storage tank 7 is replenished with the same amount of low-temperature tap water that was discharged from the hot water storage tank 7 into the bathtub 14. In other words, the amount of heat stored in the hot water storage tank 7 decreases.

The operation control unit C determines whether the water outage is not predicted to occur within the set time (No in step #10) or if the temperature after the predicted time of the water outage is less than the set temperature (step #11). If the predicted amount of heat storage at the predicted time of water outage is less than the set amount of heat storage (if “No” in step #12), proceed to step #14 and force hot water extraction. decide.

As described above, in the fuel cell system of the present embodiment, the operation control unit C performs forced hot water discharging to discharge more than a set amount of hot water from the hot water storage tank 7 via the hot water outlet path 12 until the predicted time of occurrence of water outage. By doing this, a new amount of low-temperature tap water that is higher than the set amount is stored in the hot water storage tank 7. As a result, in the hot water storage tank 7, the amount of low-temperature hot water required to sufficiently cool the combustion exhaust gas increases, so even if a water outage actually occurs, the fuel cell unit FC will continue to operate. , the combustion exhaust gas can be continuously cooled. Therefore, it is possible to provide a fuel cell system in which the fuel cell unit FC can continue to operate even if a water outage occurs.

<Another embodiment>
<1>
In the above embodiment, the configuration of the charging/discharging system has been described using a specific example, but the configuration can be changed as appropriate.
For example, in the above embodiment, the water tank 10 is configured to store only the recovered water recovered from the combustion exhaust gas, but other recovered water may be stored in the water tank 10. For example, the moisture contained in the cathode exhaust gas discharged from the cathode 3 may be cooled and condensed in the heat exchanger 6, and the condensed water may be stored in the water tank 10.

<2>
In the above embodiment, the recovered water shortage condition has been explained by giving an example, but other conditions may be used as the recovered water shortage condition.
For example, if the predicted maximum temperature in the area where the fuel cell unit FC is installed from the predicted time of water outage to after a predetermined period of time has passed is equal to or higher than the set temperature, the operation control unit C determines that the recovered water shortage condition is It is also possible to determine that the conditions are satisfied.

<3>
In the above embodiment, what kind of information is provided from the information providing server device 27 to the water outage possibility prediction unit 26, and what method the water outage possibility prediction unit 26 uses to predict whether or not a water outage will occur. It can be set as appropriate as to whether or not it is determined.
For example, the water outage possibility prediction unit 26 can receive information related to fire, earthquake, etc. as information related to disasters from the information providing server device 27. The water outage possibility prediction unit 26 refers to the transmitted fire prediction range information and predicts whether a fire will occur if the water distribution equipment for supplying water to the fuel cell unit FC is included in the fire prediction range. It can be determined that a water outage is predicted to occur during the predicted time period. In addition, the water outage possibility prediction unit 26 refers to the transmitted earthquake information and determines whether a strong earthquake is predicted to occur in the area where the fuel cell unit FC is installed, If the time period in which a strong earthquake is predicted to occur in the area where the earthquake is expected to occur is announced, it can be determined that a water outage is predicted to occur during that predicted time period.
In addition, the water outage possibility prediction unit 26 can receive information regarding construction of water pipes and the like and information regarding events such as planned power outages from the information providing server device 27 . For example, the water outage possibility prediction unit 26 refers to the transmitted water distribution pipe construction information, and determines whether the construction time period It can be determined that a water outage is predicted to occur in the area. In addition, the water outage possibility prediction unit 26 refers to the information on the planned power outage and determines whether the scheduled power outage will occur if the installation location of water distribution equipment for supplying water to the fuel cell unit FC is included in the scope of the planned power outage. It can be determined that a water outage is predicted to occur during the power outage period.

<4>
The configuration disclosed in the above embodiment (including another embodiment, the same applies hereinafter) can be applied in combination with the configuration disclosed in other embodiments, unless a contradiction occurs, and the configuration disclosed in this specification can be applied in combination with the configuration disclosed in other embodiments. The embodiments are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the purpose of the present invention.

INDUSTRIAL APPLICATION This invention can be utilized for the fuel cell system which can continue operation of a fuel cell part even if a water outage occurs.

1 Reforming section 2 Anode 3 Cathode 5 Combustion section 6 Heat exchange section 7 Hot water storage tank 10 Water tank 12 Hot water outlet 13 Water supply channel 14 Bathtub 26 Water cutoff possibility prediction section C Operation control section FC Fuel cell section H Heat recovery device

Claims (4)

a fuel cell section having a reforming section that steam-reforms raw fuel to produce fuel gas; an anode to which the fuel gas generated in the reforming section is supplied; and a cathode to which oxygen gas is supplied. a combustion section that burns fuel components in anode exhaust gas discharged from the anode after being used in the power generation reaction in the fuel cell section; and a heat exchange section to which the combustion exhaust gas discharged from the combustion section is supplied. and a hot water storage tank for storing hot water, the hot water taken out from the lower part of the hot water storage tank is supplied to the heat exchange part, and the hot water flowing through the heat exchange part is returned to the upper part of the hot water storage tank, so that the hot water is circulated. A heat recovery device configured to store the heat of the combustion exhaust gas recovered in the heat exchange section in the hot water storage tank; A fuel cell comprising a water tank for storing collected recovered water and an operation control section for controlling operation, wherein the water stored in the water tank is used for steam reforming of the raw fuel in the reforming section. A system,
The hot water storage tank is connected to a hot water outlet that discharges hot water to the outside of the hot water storage tank, and a water supply channel that is connected to the lower part of the hot water storage tank, and the hot water inside the hot water storage tank is connected to the water supply channel through the water supply channel. When a predetermined water supply pressure is applied, water is supplied from the hot water supply channel into the hot water storage tank in response to hot water being discharged from the hot water supply channel,
comprising a water outage possibility prediction unit that predicts the occurrence and predicted time of occurrence of a water outage in which water will not be supplied from the water supply channel to the hot water storage tank in a district where the fuel cell unit is installed;
The operation control unit is configured to perform a water outage when a water outage is predicted to occur and a recovered water shortage condition indicating that the amount of recovered water in the water tank will tend to be insufficient after the predicted time of occurrence of the water outage is satisfied. Performing forced hot water discharging to discharge more than a set amount of hot water from the hot water storage tank through the hot water outlet path until the predicted occurrence time,
The operation control unit predicts that the predicted maximum temperature from the predicted time of occurrence of the water outage until after a predetermined period of time has passed is equal to or higher than the set temperature, and that the hot water is stored in the storage tank at the predicted time of occurrence of the water outage. A fuel cell system that determines that the recovered water shortage condition is satisfied when a predicted amount of heat storage is equal to or greater than a set amount of heat storage . If it is predicted that hot water in the hot water storage tank will be filled into the bathtub via the hot water supply path before the predicted time of occurrence of water outage, the operation control unit may control the operation of the hot water storage tank at the predicted time of occurrence of water outage. The fuel cell system according to claim 1, wherein the predicted amount of heat storage is predicted to be less than the set amount of heat storage. 3. The fuel cell system according to claim 1 , wherein the operation control unit discharges the set amount of hot water from the hot water storage tank into a bathtub as the forced hot water discharge. The water outage possibility prediction unit predicts the occurrence of water outage and the predicted time of occurrence based on atmospheric pressure data in the area where the fuel cell unit is installed . fuel cell system.

Images