JP2010238428A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system which extends the remaining lifetime of a purifying section, when deterioration of the purifying section progresses. <P>SOLUTION: The fuel cell system has a purifying section 51, which is maintained periodically or irregularly, and a control section 7 which controls a transfer source 53. The control section 7, when deterioration of the purifying section 51 progresses; reduces the flow-rate per unit time of a fluid passing through the purifying section 51 and carries out a remaining lifetime extension treatment for extending the remaining lifetime of the purifying section 51; and delays the maintenance period of the purifying section 51. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel cell system having a purification unit represented by a filter for purifying a cathode fluid.

  Patent Document 1 discloses a fuel cell system in which maintenance parts are provided in the vicinity of a front panel of a housing so that maintenance can be easily performed. Maintenance parts include a filter that removes dust contained in the cathode gas, a desulfurizer that removes sulfur components contained in the fuel raw material that becomes the anode gas, and a purification device that removes water impurities from the heat recovery device. Yes. Patent Document 2 discloses a fuel cell system in which a dust removing filter is provided at an intake port for taking in a cathode gas.

JP 2006-140165 A JP 2007-123055 A

  According to the above-described technology, when the maintenance time of the maintenance part arrives, the user or the maintenance person appropriately maintains the maintenance part. The technology described above is not intended to extend the end of the remaining life of maintenance parts. Maintenance costs are affected by the price of maintenance parts. Furthermore, when there is no maintenance center nearby, for example, in remote locations or remote locations, the maintenance costs may be higher than necessary due to the influence of the transportation costs of the maintenance personnel. May not be ignored by the user.

  The present invention has been made in view of the above-described circumstances, and provides a fuel cell system capable of extending the remaining life of the purification unit and delaying the maintenance time of the purification unit as the purification unit progresses. Let it be an issue.

  A fuel cell system according to the present invention includes a fuel cell that is supplied with an anode fluid and a cathode fluid to generate power, a purification unit that purifies the fluid used in the fuel cell and that is regularly or irregularly maintained, and a fluid. A conveyance source for conveyance and a control unit for controlling the conveyance source are provided. The control unit reduces the flow rate per unit time of the fluid passing through the purification unit as the purification unit progresses, thereby purifying the purification unit. The remaining life extension process for extending the remaining life of the cleaning section is executed to delay the maintenance time of the purification section. As the purification unit progresses, the control unit reduces the flow rate per unit time of the fluid that passes through the purification unit, executes a remaining life extension process that extends the remaining life of the purification unit, and maintains the purification unit. Delay time.

  According to the present invention, even if deterioration of the purifying unit proceeds, the flow rate per unit time of the fluid passing through the purifying unit is decreased to extend the remaining life of the purifying unit. Thereby, the maintenance time of a purification | cleaning part can be delayed. This is advantageous when the maintenance cost is high in remote areas or remote areas.

1 is a diagram illustrating a concept of a fuel cell system according to Embodiment 1. FIG. It is a block diagram regarding a control part. It is a flowchart which a control part performs. It is a flowchart which a control part performs. It is a flowchart which a control part performs. It is a flowchart which a control part performs. It is a flowchart which a control part performs.

  The conveyance source is provided in the anode fluid supply passage or the cathode fluid supply passage, and conveys the fluid through the purification unit, and examples thereof include a pump, a fan, a compressor, and a blower. Examples of the purification unit include a filter that reduces the dust contained in the cathode fluid supplied to the cathode of the fuel cell to purify the cathode fluid. Furthermore, the purification unit includes a desulfurizer that purifies the fuel material by desulfurizing sulfur components contained in the fuel material of the anode fluid supplied to the anode of the fuel cell, and a water purifier that purifies and purifies the water in the system. At least one of them is exemplified. The above-described filters, desulfurizers, and water purifiers are often maintenance parts that are regularly or irregularly maintained. The above-described filters, desulfurizers, and water purifiers reduce the purification ability unless maintained. However, the maintenance cost may not be ignored by the user.

  According to the preferable form of this invention, the maintenance component maintained regularly or irregularly is provided in addition to the purification | cleaning part by which a remaining life extension process is carried out. In this case, the control unit has a storage unit for storing the next maintenance time of the maintenance part subjected to the remaining life extension process. In this case, in the remaining life extension process, the control unit reduces the flow rate per unit time of the fluid passing through the purification unit so that the next maintenance time of the purification unit matches the next maintenance time of the maintenance parts, The remaining life extending process for extending the remaining life of the purification unit is executed to delay the maintenance time of the purification unit.

  According to a preferred embodiment of the present invention, the control unit has a storage unit for storing the next maintenance time of maintenance parts other than the purification unit subjected to the remaining life extension process. In this case, in the remaining life extension process, the control unit passes through the purification unit as the purification unit progresses so that the next maintenance time of the maintenance unit other than the purification unit matches the next maintenance time of the purification unit. A remaining life extending process for extending the remaining life of the purification unit is performed by reducing the flow rate per unit time for transporting the fluid to the fuel cell, thereby delaying the maintenance time of the purification unit.

  According to a preferred embodiment, the purification unit can be a filter that purifies the cathode fluid supplied to the cathode of the fuel cell. Examples of maintenance parts other than the purification unit include a desulfurizer and / or a water purifier. In this case, according to a preferred embodiment of the present invention, the control unit has a storage unit for storing the next maintenance time of maintenance parts (desulfurizer and / or water purifier) other than the filter subjected to the remaining life extension process. In this case, in the remaining life extending process, the deterioration of the filter progresses so that the next maintenance time of the filter matches the next maintenance time of the maintenance parts (desulfurizer and / or water purifier) other than the filter. Then, the flow rate per unit time for transporting the fluid passing through the filter to the fuel cell is decreased, the remaining life of the filter is extended, the remaining life extending process is executed to delay the end of the remaining life, and the filter maintenance is performed. The time can be delayed.

  According to a preferred embodiment, the purification unit can be a desulfurizer that purifies the fuel material of the anode fluid. In this case, the maintenance parts other than the desulfurizer include a filter and / or a water purifier. In this case, according to a preferred embodiment of the present invention, the control unit has a storage unit for storing the next maintenance time of maintenance parts (filter and / or water purifier) other than the desulfurizer subjected to the remaining life extension process. In this case, in the remaining life extension process, the control unit causes the desulfurizer to deteriorate so that the next maintenance time of the filter is aligned with the next maintenance time of the maintenance parts (filter and / or water purifier) other than the desulfurizer. As it progresses, the flow rate per unit time for transporting the fuel raw material that passes through the desulfurizer is decreased, and the remaining life extension process for extending the remaining life of the desulfurizer is executed to delay the maintenance time of the desulfurizer. it can.

  According to a preferred embodiment, the purification unit can be a water purifier that purifies water in the system. In this case, the maintenance parts other than the water purifier include a filter and / or a desulfurizer. In this case, according to a preferred embodiment of the present invention, the control unit has a storage unit for storing the next maintenance time of maintenance parts (filter and / or desulfurizer) other than the water purifier subjected to the remaining life extension process. In this case, in the remaining life extension process, the control unit adjusts the water purifier next maintenance time to the next maintenance time of maintenance parts (filter and / or desulfurizer) other than the water purifier. When deterioration of the water purifier progresses, the flow rate per unit time for transporting the water that passes through the water purifier is decreased, and the remaining life extension process is performed to extend the remaining life of the water purifier, so that the maintenance time of the water purifier Can be delayed.

  According to a preferred embodiment, the remaining life of the desulfurizer is determined based on the anode activity such as the cumulative amount of fuel (cumulative molar amount) that passes through the desulfurizer, the cumulative amount of power generation, the cumulative operation time, the cumulative number of start / stops, It can be determined based on at least one of factors such as the substance utilization rate. According to a preferred embodiment, there is provided a setter for setting a threshold value that defines the content of the remaining life extension process. A threshold is set from a setting device in accordance with the installation location of the system and the content of the remaining life extension process is adjusted. According to a preferred form of the invention, the anode fluid is an anode gas supplied to the anode of the fuel cell and the cathode fluid is a cathode gas supplied to the cathode of the fuel cell.

(Embodiment 1)
FIG. 1 shows the concept of the first embodiment. A fuel cell system (hereinafter also referred to as a system) includes a stack 1 formed of a fuel cell, an anode gas supply system 2 that supplies fuel to the anode 10 of the stack 1, and a cathode that supplies cathode gas to the cathode 11 of the stack 1. It has a gas supply system 5, a cooling system 6 for cooling the stack 1, and a control unit 7. The anode gas supply system 2 is provided in the anode gas supply passage 20 that connects the fuel raw material source 21 and the anode 10 of the stack 1, the desulfurizer 31 provided in the anode gas supply passage 20, and the anode gas supply passage 20. A fuel valve 22 and a fuel pump 23 (a fuel raw material transport source); a reformer 24 provided in the anode gas supply passage 20 for reforming the fuel raw material with water vapor to form gaseous fuel; and the anode gas supply passage 20 A condenser 27 for reducing the moisture of the anode gas, an inlet valve 28 for opening and closing the anode gas supply passage 20, an anode off gas discharge passage 29 for discharging the anode off gas discharged from the anode 10 of the stack 1, and an anode And an outlet valve 30 provided in the off-gas discharge passage 29.

  As shown in FIG. 1, the desulfurizer 31 is provided upstream of the reforming unit 25 in the anode gas supply passage 20 and has a desulfurizing agent that reduces the sulfur component contained in the fuel material and purifies the fuel material. Maintenance parts that are regularly or irregularly maintained.

  The stack 1 has a large number of membrane electrode assemblies (MEAs). The MEA includes a solid polymer type ion conductive film 12 (for example, a fluorine-based film, a hydrocarbon-based film, an inorganic film, or a mixed organic and inorganic film) sandwiched between an anode 10 and a cathode 11. Have. A fuel cell generates electric energy by an oxidation-reduction reaction. The MEA may be a sheet type or a tube type. The stack 1 is connected to a commercial power source 49 through a circuit breaker 47 such as a breaker and an inverter 48, and is linked to the system. When the power of the stack 1 is insufficient, the control unit 7 adds the power of the commercial power supply 49 to generate a power load (for example, an internal load provided inside the system or an external load provided outside the system). Operate.

  Further, as shown in FIG. 1, the anode gas supply system 2 (anode fluid supply system) is provided in the branch path 40 that connects the anode gas supply path 20 and the burner 26, the air path 41, and the air path 41. And a pump 42 (combustion air conveyance source). The fuel material of the fuel material source 21 is supplied from the branch path 40 to the burner 26 as a combustion fuel. When the pump 42 is operated, combustion air is supplied to the burner 26. As a result, the combustion fuel is burned by the combustion air in the burner 26 to heat the reforming section 25. In addition, the fuel raw material reformed in the reforming unit 25 may be gaseous or liquid, and specifically, city gas (natural gas, etc.), LPG, kerosene, methanol, dimethyl ether, gasoline, biogas, etc. Is exemplified. The exhaust gas after being burned by the burner 26 is discharged to the outside air through the exhaust gas passage 90 and the condenser 91.

  As shown in FIG. 1, the cathode gas supply system 5 (cathode fluid supply system) includes a humidifier 50 having a moisture retaining member 50c that partitions the humidification path 50a and the moisture absorption path 50b, and the humidification path 50a of the humidifier 50. A cathode gas supply passage 52 (cathode fluid supply passage) for supplying the cathode gas (air) to the cathode 11 of the stack 1, and a cathode gas pump 53 (cathode fluid transport source, transport source) provided in the cathode gas supply passage 52 ), A dust removal filter 51 (purification unit) provided in the cathode gas supply passage 52, an inlet valve 54 for opening and closing the cathode gas supply passage 52, and a cathode off-gas discharged from the cathode 11 of the stack 1 The cathode off gas discharge passage 55 for discharging through the 50 moisture absorption paths 50b and the condenser 52x, and the cathode off A return path bypass circuit 56 that communicates with the gas discharge path 55 and bypasses the moisture absorption path 50 b of the humidifier 50, and a return path bypass valve 57 that flows the cathode off-gas discharged from the cathode 11 of the stack 1 to the bypass path 56. Have. The moisture retention member 50c of the humidifier 50 has moisture retention and gas barrier properties, and is formed of, for example, an ion exchange membrane. As can be understood from FIG. 1, the bypass valve 57 can change the ratio of the flow rate flowing in the moisture absorption path 50 b of the humidifier 50 and the flow rate flowing in the bypass path 56. Further, the detour 58 for the forward path that communicates with the cathode gas supply passage 52 and bypasses the humidification path 50 a of the humidifier 50, and the forward path for flowing the cathode gas immediately before being supplied to the cathode 11 of the stack 1 to the detour 58. And a bypass valve 59. The bypass valve 59 can change the ratio of the flow rate flowing through the humidification path 50 a of the humidifier 50 and the flow rate flowing through the bypass circuit 58. In some cases, the detour 58 for the forward path and the detour valve 59 for the forward path can be eliminated. The filter 51 reduces dust contained in the cathode gas, and is a maintenance component that is regularly or irregularly maintained.

  As shown in FIG. 1, a reformer 24 includes a reformer 25 that reforms a fuel material with gas-phase or liquid-phase water, and a burner that heats the reformer 25 so as to be suitable for the reforming reaction. 26 (heating unit). A reforming water system 34 for supplying reforming gas phase or liquid phase water to the reforming unit 25 is provided. The reforming water system 34 includes a tank 35 that receives condensed water condensed by the condenser of the system and stores it as reforming water, a reforming water passage 36 that connects the tank 35 and the reforming unit 25, and reforming. A water purifier 33 provided downstream of the tank 35 in the water passage 36, a water pump 37 (water transport source) and a water valve 38 provided in the reforming water passage 36, and liquid phase water is vaporized. And an evaporating section 39 that converts the water vapor into water vapor. The water purifier 33 has a water purification material such as an ion exchange resin that purifies the water by reducing impurities contained in water such as condensed water, and is regularly or irregularly maintained. Maintenance parts. The evaporation unit 39 may be separate from the reformer 24 or may be mounted on the reformer 24. The condensed water condensed in the condensers 52x, 91, 27 in the system is accumulated in the tank 35 disposed below the condensers 52x, 91, 27 in the direction of gravity. The water stored in the tank 35 is purified by the water purifier 33 to increase the purity of the water, and is supplied to the evaporating unit 39 as reforming water to be steamed.

  According to this embodiment, the above-described filter 51, desulfurizer 31 and water purifier 33 are maintenance parts, and are regularly or irregularly maintained. In order to reduce the maintenance cost as much as possible, at the time of designing the system, the filter 51, the desulfurizer 31 and the water are arranged so that the maintenance time of the filter 51, the desulfurizer 31 and the water purifier 33 can be basically the same. The capacity and material of the purifier 33 are set. However, when the installation location of the fuel cell system is changed, the maintenance time of the filter 51 may vary from the maintenance time of the desulfurizer 31 and the water purifier 33. The reason for this is that dust, etc. contained in the outside air, which is the cathode gas, is the place where the fuel cell system is installed (residential, industrial, mountainous, areas near highways, areas near unpaved roads, This is because it is easily affected by a large area).

  The cooling system 6 includes a circulation path 60 that communicates with the refrigerant passage 13 formed inside the stack 1, and a refrigerant pump 61 (refrigerant transport source) that circulates refrigerant (cooling liquid such as cooling water) in the circulation path 60. And a temperature sensor 62 that is provided in the circulation path 60 and detects the temperature of the refrigerant in the circulation path 60, and a heater 63 (power consumption element) that heats the refrigerant in the circulation path 60. When the refrigerant pump 61 is activated, the refrigerant circulates in the circulation path 60 and the refrigerant path 13 and can take heat of the stack 1. When the stack 1 is activated, the control unit 7 can preheat the stack 1 by causing the heater 63 to generate heat and preheating the refrigerant in the circulation path 60. The temperature of the refrigerant in the circulation path 60 substantially corresponds to the operating temperature of the stack 1.

  As shown in FIG. 1, a hot water storage system 8 is provided. The hot water storage system 8 includes a hot water storage passage 80, a heat exchanger 81 that exchanges heat between the circulation path 60 and the hot water storage passage 80, a pump 82 (a hot water supply source) that transfers water in the hot water storage passage 80, and the hot water storage passage 80. It has a hot water tank 85 that is connected, and a replenishment passage 84 that replenishes replenished water (for example, tap water) when the water in the hot water tank 85 is insufficient. When the pump 82 is activated, the water in the hot water storage passage 80 is conveyed, the thermal energy of the circulation path 60 is transmitted to the hot water storage passage 80, the water temperature of the hot water storage passage 80 rises, and the thermal energy (hot water) is eventually supplied to the hot water storage tank 85. Accumulated.

  As shown in FIG. 2, the control unit 7 includes an input processing unit 7a, a CPU 7c having a timer function, a memory 7d, and an output processing unit 7e. The fuel valve 22, fuel pump 23, pump 42, refrigerant pump 61, cathode gas pump 53, inlet valve 28, outlet valve 30, inlet valve 54, bypass valve 57, and the like are controlled. The control unit 7 defines the contents of the temperature sensor 72, the voltage sensor 1a for detecting the generated voltage of the stack 1, the current sensor 1c for detecting the generated current of the stack 1, and the remaining life extension process via the input processing unit 7a. Signals of a setting device 1d for setting a threshold, an execution switch 1e for executing the remaining life extension process, a cancel switch 1f for canceling the execution of the remaining life extension process, and a start switch 1x for starting the system are input.

  In a predetermined area of the memory 7d, data relating to the power consumption history in the time zone MA (for example, from Monday to Sunday one week before) can be stored. The data related to the power consumption history includes power generation data of power generated by the stack 1, the amount and cost of fuel material used, power data purchased from the commercial power source 49, and power cost purchased from the commercial power source 49. Further, in the predetermined area of the memory 7d, the previous maintenance time, the next maintenance time and the maintenance cost of the filter 51 are stored, and the previous maintenance time, the next maintenance time and the maintenance cost of the desulfurizer 31 are stored. In addition, the previous maintenance time, the next maintenance time, and the maintenance cost of the water exchanger 33 are stored. When the filter 51, the desulfurizer 31, and the water exchanger 33 are replaced, signals from the switch 51r of the filter 51, the switch 31r of the desulfurizer 31, and the switch 33r of the water exchanger 33 are input to the control unit 7, and the previous time Stored as the maintenance time (corresponding to the current maintenance time). The next maintenance time is calculated by the control unit 7 and stored in the area of the memory 7d. Instead of the signal from the switch, the operator (maintenance person) may input the previous maintenance time and / or the current maintenance time from the operation panel (such as the dip switch on the operation board). The previous maintenance time may be stored in the control unit 7 from the confirmation operation signal. Since the maintenance is performed in the order of the previous time and the next time, the previous maintenance time corresponds to the maintenance time performed this time.

  During the power generation operation of the stack 1, the control unit 7 operates the fuel pump 23 with the fuel valve 22 opened while the stack 1 and the electric load are electrically connected, and the hydrocarbon-based fuel source source 21. The fuel material is supplied to the reforming unit 25 of the reformer 24, and the water pump 37 is operated, and the reforming water in the water tank 35 is vaporized by the evaporation unit 39 and then supplied to the reforming unit 25. As a result, the fuel material is steam reformed in the reforming unit 25 to become 35 anode gas (hydrogen-containing gas). The anode gas is supplied to the anode 10 of the stack 1 through an open inlet valve 28 after excess moisture is removed by the condenser 27. Further, the control unit 7 operates the cathode gas pump 53 with the inlet valve 54 opened to allow the cathode gas to pass through the filter filter 51 and then humidify the humidification passage 50a of the humidifier 50, and then stack 1 To the cathode 11. As a result, the stack 1 performs a power generation operation.

  The anode off gas discharged from the anode 10 of the stack 1 is discharged from the anode off gas discharge passage 29 to the outside or the burner 26. Cathode off gas discharged from the cathode 11 of the stack 1 flows from the cathode off gas discharge passage 55 to the moisture absorption path 50b of the humidifier 50 and is absorbed by the moisture absorption path 50b. By controlling the bypass valve 57, it is possible to variably control the ratio between the flow rate of the cathode off gas flowing through the moisture absorption path 50b of the humidifier 50 and the flow rate of the cathode off gas flowing through the bypass circuit 56.

  If the cathode gas is supplied to the cathode 11 of the stack 1 at a relative flow rate of 100 per unit time, the control unit 7 instructs the pump 53 (conveying source) when the filter 51 is clogged. The indicated value gradually increases. The instruction value basically corresponds to the duty value of the pump 53. The higher the indicated value, the more the load on the pump 53 increases. When the accumulated time of the power generation operation of the stack 1 becomes longer, the clogging of the filter 51 functioning as a purification unit gradually proceeds. For this reason, when conveying the same amount of cathode gas to the stack 1, the indicated value of the pump 53 becomes high.

  When the deterioration (clogging) of the filter 51 proceeds, the flow rate of the cathode gas is restricted, and the power generation output of the stack 1 is reduced. However, it is preferable to replace the filter 51. However, there are times when the maintenance cost cannot be ignored by the user. In this regard, according to the present embodiment, when the deterioration (clogging) of the filter 51 proceeds, the control unit 7 causes the cathode gas (cathode fluid) passing through the filter 51 to be transported to the cathode 11 of the stack 1 per unit time. By reducing the flow rate, the remaining life of the filter 51 is extended, and the remaining life extending process for delaying the end of the life is executed.

  Specifically, when the indicated value of the pump 53 is longer than the predetermined value and continues for a predetermined time, the control unit 7 determines that the clogging of the filter 51 has progressed, and decreases the power generation instruction value of the stack 1. The indicated value of the pump 53 is lowered, and the flow rate per unit time of the cathode gas (air) that passes through the filter 51 and is supplied to the cathode 11 of the stack 1 is lowered.

  In this case, the control unit 7 also decreases the instruction value of the fuel pump 23 and decreases the flow rate of the fuel raw material per unit time that the fuel pump 23 supplies to the reforming unit 25. Similarly, the flow rate of reforming water per unit time supplied by the water pump 37 to the evaporator 39 is also reduced. In this case, the power generation output generated by the stack 1 decreases. If the power is insufficient, the inverter 48 is controlled by the control unit 7, and the power from the commercial power source 49 is supplied to the fuel cell system side to the power load side. Also in this embodiment, as in the embodiment described later, it is determined whether or not the end of the remaining life of the filter 51 can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, and the filter 51 If the end of the remaining life can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, the remaining life of the filter 51 may be extended so as to match.

(Embodiment 2)
FIG. 3 shows a second embodiment. FIG. 3 shows a flowchart executed by the control unit 7. The higher the indicated value (corresponding to the duty ratio) of the pump 53 corresponds to the higher rotation speed (driving amount) of the pump 53 per unit time for transporting the same amount of cathode gas, so the filter 51 is clogged. Presumed to be progressing. As illustrated in FIG. 3, the control unit 7 determines whether the power generation operation is performed in a state where the filter 51 is clogged. That is, the control unit 7 determines whether or not the indicated value of the pump 53 is P10 or more and continues for T10 min or more (step S102). If it is not continued (NO in step S102), it is estimated that the filter 51 is not clogged so much, so the process returns to the main routine without performing the remaining life extension process of the filter 51.

  If it continues (YES in step S102), it is estimated that clogging of the filter 51 has started to proceed considerably. Therefore, in order to extend the remaining life of the filter 51, the control unit 7 decreases the power generation instruction value of the stack 1 by ΔQ [W] until the power generation output of the stack 1 becomes equal to or lower than Q1 [W] (step S106). (Step S104). The power generation instruction value may or may not be an instruction value of the highest generated power of the stack 1 in the system. As described above, as the power generation instruction value of the stack 1 decreases, the control unit 7 also decreases the instruction value of the fuel pump 23, and the flow rate of the fuel raw material per unit time that the fuel pump 23 supplies to the reforming unit 25 also increases. Reduce. Similarly, the flow rate of reforming water per unit time supplied by the water pump 37 to the evaporator 39 is also reduced. Then, until the cumulative operation time of the stack 1 after the previous maintenance reaches Y1 (for example, 1000 hours), the power generation operation is performed in a state where the power generation output of the stack 1 is reduced to Q1 [W] or less. This extends the life of the filter 51 and delays the end of the life. When power is insufficient, power is automatically supplied from the commercial power supply 49.

  If the power generation output of the stack 1 decreases to Q1 or less due to clogging of the filter 51 (YES in step S106), the control unit 7 determines that the cumulative operation time of the stack 1 after the previous maintenance is Y1 (for example, 1000 hours). It is determined whether or not this is the case (step S108). If NO in step S108, it is estimated that the indicated value of the pump 53 is high and the clogging of the filter 51 is progressing despite the relatively short cumulative operation time of the stack 1 being Y1. The In this case, the power generation output of the system decreases and the power generation cost increases. For this reason, the control part 7 performs the notification 1 which notifies that to a user or a maintenance person (step S130). The notified user or maintenance person preferably maintains the filter 51. When the installation location of the system is a place with a lot of dust or the like, the filter 51 is clogged even when the cumulative operation time of the stack 1 after the previous maintenance is short. The installation environment of the system greatly affects the progress of clogging of the filter 51.

  After performing the notification 1, the control unit 7 determines whether or not the indicated value of the pump 53 is P11 or more (P11> P10) and continues for the time T11min or more (step S132). That is, the control unit 7 determines whether or not the filter 51 is further clogged in step S132. If it continues (YES in step S132), the accumulated operation time of the stack 1 is less than Y1, and the filter 51 is affected by the installation location of the system and the filter 51 is clogged despite being relatively short. Is estimated to progress early. For this reason, the control part 7 implements the electric power generation stop determination process (step S134) which determines whether the electric power generation of the stack 1 is stopped. In the power generation stop determination process (see FIG. 4), the control unit 7 reads the power consumption history data stored in the area of the memory 7d (step S180). Examples of the data related to the power consumption history include power generation data generated by the stack 1, the amount and cost of fuel material used, and power data purchased from the commercial power source 49.

  Next, the control unit 7 extends the remaining life of the clogged filter 51 until the next maintenance time of the filter 51, while reducing the power generation output of the stack 1 and operating the fuel at the expected cost C <b> 1. After interrupting the power generation in the battery system and maintaining the filter 51 by a maintenance person, a profit / loss calculation is performed to compare with the expected cost C2 when the fuel cell system is generated again (step S182). The expected cost C2 includes a maintenance cost.

  If the expected cost C1 is higher than the expected cost C2 and the power generation is lost (YES in step S184), the power generation of the stack 1 is stopped (step S186), and the user or maintenance person is notified of the maintenance of the filter 51 Is executed (step S188), and the process returns to the main routine. If the expected cost C1 is lower than the expected cost C2 and the power generation of the stack 1 is profitable (NO in step S184), the power generation operation of the stack 1 is continued with the filter 51 being clogged (NO in step S184). ).

  When the cumulative operation time of the stack 1 is equal to or longer than Y1 (eg, 1000 hours) as a result of the determination in step S108 described above (YES in step S108), the control unit 7 indicates that the indicated value of the pump 53 is P12 (P12> P10). As described above, it is determined whether or not it continues for time T12 min or longer (step S110). That is, the control unit 7 determines whether or not the filter 51 is further clogged.

  If not continued (NO in step S110), that is, the clogging of the filter 51 is within the allowable range, and the filter 51 is not abnormal. For this reason, the power generation operation is performed while reducing the power generation output of the stack 1 while the indicated value of the pump 53 is maintained. Thus, the control unit 7 allows the stack 1 to perform a power generation operation while reducing the power generation output of the stack 1 while allowing the filter 51 to be clogged and extending the remaining life of the filter 51. In this case, the supply flow rate per hour of the cathode gas supplied to the cathode of the stack 1 is reduced and the progress of clogging of the filter 51 is suppressed, so that the remaining life of the filter 51 through which the cathode gas passes is extended. .

  If the indicated value of the pump 53 is P12 (P12> P10) or more and continues for the time T12min or longer (YES in Step S110), it is considered that the filter 51 has further clogged. Therefore, the control unit 7 decreases the power generation instruction value of the stack 1 by ΔQ [W] until the power generation output of the stack 1 becomes equal to or lower than Q2 [W] (Q2 <Q1) (steps S112 and S114). A decrease in the power generation instruction value of the stack 1 corresponds to a decrease in the supply flow rate per hour of the cathode gas supplied to the cathode of the stack 1 via the filter 51, and the clogging of the filter 51 progresses. Delay. Therefore, the remaining life of the filter 51 through which the cathode gas passes is extended. That is, the controller 7 extends the remaining life of the filter 51 while reducing the power generation output of the stack 1. In this case, when the power is insufficient, power is supplied from the commercial power source 49.

  If the power generation output of stack 1 falls below Q2 [W] (YES in step S114), control unit 7 determines whether or not the cumulative operation time after the previous maintenance is Y2 (for example, 2000 hours) or more (step) S116). If the power generation output of the stack 1 is reduced to less than Q2 (NO in step S116) even though the cumulative operation time is less than Y2, it is estimated that the clogging of the filter 51 has progressed considerably. For this reason, the control part 7 performs the notification 3 which notifies a user or a maintenance person (step S140). Accordingly, it is preferable to perform maintenance of the user or maintenance person filter 51.

  Even after the notification 3 is executed, the control unit 7 continues to reduce the power generation output of the stack 1 until the indicated value of the pump 53 continues for P13 (P13> P10, P13> P12) and continues for the time T13min. The power generation operation is continued (step S142). That is, even when the clogging of the filter 51 is in progress, the control unit 7 reduces the power generation output of the stack 1 and reduces the remaining life of the filter 51 as long as the clogging is within an allowable range. Plan to extend If the indicated value of pump 53 is P13 (P13> P10) or more and continues for time T13min or more (YES in step S142), it is estimated that clogging of filter 51 has progressed considerably. For this reason, the control part 7 performs the electric power generation stop determination process of the stack 1 (step S144).

  In the power generation stop determination process, as described above, the control unit 7 performs the profit / loss calculation for comparing the predicted cost C1 and the predicted cost C2, and if the predicted cost C1 is higher than the predicted cost C2 and the power generation is a loss. Then, the power generation of the stack 1 is stopped, the passage for notifying the user or the maintenance person of that is executed, and the process returns to the main routine. If the expected cost C1 is lower than the expected cost C2 and the remaining life extension process is profitable, the power generation of the stack 1 is continued. Even if the power generation output of the stack 1 has decreased to Q2 [W] or less (YES in step S114), if the accumulated operation time is Y2 or more from the previous maintenance time (YES in step S116), the filter 51 Is within an allowable range, and the control unit 7 causes the stack 1 to perform a power generation operation while allowing a decrease in the power generation output and the filter 51 to be clogged.

  That is, the control unit 7 decreases Q2 [W] and changes Q2, P12, and Y2 in a direction to increase the instruction value P12 and the cumulative operation time Y2 (step S118). The change count is incremented by 1 (step S120). If the number of change counts is less than NA (NO in step S122), the process proceeds to step S110, and the same control (remaining life extension process of the filter 51) is executed. As a result, as the cumulative operation time from the previous filter maintenance becomes longer, the control unit 7 gradually reduces the power generation output of the stack 1 while extending the remaining life of the filter 51 and delays the end of the life. .

  If the power generation output of the stack 1 is equal to or greater than Q3 [W], the clogging of the filter 51 is within an allowable range, so the control unit 7 maintains the indicated value of the pump 53 and reduces the power generation output. The power generation is continued (NO in step S124). However, if the power generation output of stack 1 is less than Q3 [W] (YES in step S124), it is estimated that clogging of filter 51 has progressed considerably. Furthermore, the power generation output is reduced, and the power generation cost of the system is increased. For this reason, the control part 7 performs the electric power generation stop determination of the stack 1 (step S144). In the power generation stop determination process, as described above, the control unit 7 performs a profit / loss calculation for comparing the expected cost C1 and the expected cost C2. If the expected cost C1 is higher than the expected cost C2 and the power generation is a loss, the remaining life extension process is terminated, a passage for notifying the user or maintenance person is executed, and the process returns to the main routine. If the expected cost C1 is cheaper than the expected cost C2 and the remaining life extension process is profitable, the remaining life extension process is continued.

  According to the present embodiment, data such as the cumulative operation times Y1, Y2, times T10, T12, T13, the indicated values P10, P12, P13 of the pump 53, the power generation outputs Q1, Q2, Q3, and the number of times NA are filtered. 51 (Purification unit) functions as a threshold value that defines the content of the remaining life extension process, but can be arbitrarily stored in a predetermined area of the memory 7d from the setting device 75 by the user, system installer, maintenance person, etc. It is preferable that However, it may be set in advance. Note that T10 = T12 = T13 may be used. T10≈T12≈T13 may be used. Alternatively, T10 <T12 <T13 may be satisfied, or T10> T12> T13 may be satisfied. Further, the clogging of the filter 51 is greatly influenced by the installation location of the fuel cell system as compared with the desulfurizer 31 and the water purifier 33, and therefore can be arbitrarily set from the setting device 75 according to the installation location of the system. Is meaningful. In particular, it is significant that the cumulative operation time Y1, Y2, etc. can be arbitrarily set from the setting device 75 in accordance with the installation location of the system. Also in this embodiment, as in the embodiment described later, it is determined whether or not the remaining life of the filter 51 can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, and the remaining life of the filter 51 is determined. However, if it can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, the remaining life of the filter 51 may be extended so that it can be matched.

(Embodiment 3)
5 and 6 show the third embodiment. 5 and 6 show a flowchart of the remaining life extension process of the filter 51 (maintenance part) executed by the control unit 7. As shown in FIG. 5, the control unit 7 determines whether or not the filter 51 is clogged. In other words, the control unit 7 determines whether or not the indicated value of the pump 53 continues for a time T1min or more at P1 or more (step S204). If not continued (NO in step S204), it is estimated that the filter 51 is not clogged so much, so the determination in step S204 is continued. If the above continues, it is estimated that the filter 51 is clogged. Therefore, the control unit 7 decreases the maximum power generation output of the stack 1 by ΔQ [W] in order to extend the remaining life of the filter 51 (step S206). The maximum power generation output of the stack 1 means the maximum power generation output that can be generated by the stack 1 under the conditions.

  Here, the decrease in the maximum power generation output means that the maximum supply flow rate per unit time of the cathode gas supplied to the cathode of the stack 1 and the supply flow rate per unit time of the anode gas supplied to the anode of the stack 1 This corresponds to lowering the maximum value of the reforming water supply flow rate per unit time supplied to the evaporator 39. That is, the rotational speed (driving amount) of the cathode gas pump 53 per unit time, the rotational speed (driving amount) of the fuel pump 23 per unit time, and the rotational speed (driving amount) of the water pump 37 per unit time are reduced. It corresponds to.

  The control unit 7 waits until the stack 1 generates power at the maximum power generation output of the stack 1 in order to detect the magnitude of the maximum power generation output (NO in step S208). If the stack 1 is generating power at the maximum power generation output (YES in step S208), the control unit 7 determines whether or not the maximum power generation output of the stack 1 has decreased below Q1 [W] (step S210). . If the maximum power generation output of stack 1 exceeds Q1 [W] (NO in step S214), clogging of filter 51 is within an allowable range, and control unit 7 returns to step S204. As a result, the remaining life of the filter 51 can be extended while reducing the power generation output of the stack 1.

If the maximum power generation output of stack 1 has decreased to Q1 [W] or less (YES in step S210), control unit 7 determines whether or not the cumulative operation time from the previous maintenance of filter 51 is Y1 or more. (Step S214). Despite the short cumulative operation time from the previous maintenance being less than Y1 (NO in step S214), if the maximum power generation output of stack 1 has decreased to Q1 [W] or less (YES in step S210), the filter It is estimated that 51 clogging progresses early. The clogging of the filter 51 corresponds to the dirt of the outside air, and is because it is greatly influenced by the difference in whether the installation location of the system is a factory zone, a yellow sand generation zone, an agricultural land, or a residential area. If it is estimated that the filter 51 is clogged at an early stage, the control unit 7 performs notification 1 for informing the user or maintenance person (step S250). Accordingly, it is preferable that maintenance of the filter 51 is performed. Further, the control unit 7 determines whether or not the indicated value of the pump 53 is P11 (P11> P1) or more and continues for a time T11min or more (step S252). That is, the control unit 7 determines whether or not the filter 51 has been clogged.

  If not continued (NO in step S252), it is estimated that the filter 51 is clogged. For this reason, the control unit 7 continues the power generation operation of the stack 1 while maintaining the instruction value of the pump 53 (NO in step S252). Thereby, the remaining life of the filter 51 can be extended while reducing the power generation output of the stack 1. If it continues (YES of step S252), a power generation stop determination process is performed (step S254).

  As a result of the determination in step S214, the accumulated operation time from the previous maintenance has passed Y1 or more (YES in step S214), and the indicated value of the pump 53 is P2 (P2> P1) or more and continues for time T2min or more. Until this time, the control unit 7 maintains the maximum power generation output of the stack 1 at Q1 [W] (NO in step S216). Thereby, the remaining life of the filter 51 is extended.

  If the indicated value of the pump 53 is P2 (P2> P1) or more and continues for the time T2min or longer (YES in Step S216), the filter 51 is clogged. Therefore, the control unit 7 decreases the maximum power generation output of the stack 1 by ΔQ [W] (step S218). Further, the control unit 7 determines whether or not the stack 1 is generating power at the maximum power generation output in order to detect the maximum power generation output of the stack 1 (step S220). If the stack 1 is not generating power at the maximum power generation output, it waits until power is generated at the maximum power generation output (NO in step S220).

  If the stack 1 is generating power at the maximum power generation output (YES in step S222), the control unit 7 determines whether or not the maximum power generation output of the stack 1 has dropped below Q2 [W] (Q2 <Q1). (Step S222). If the maximum power generation output of the stack 1 is equal to or lower than Q2 [W] (YES in step S222), the control unit 7 determines that the cumulative operation time from the previous maintenance of the filter 51 is Y2 (for example, Y2 = 2000 hours, Y2> Y1) It is determined whether or not more than has elapsed (step S224).

  If the maximum power generation output is less than or equal to Q2 [W] (YES in step S222), and the accumulated operation time from the previous maintenance has passed Y2 or more (YES in step S224), the maximum power generation output is set to Q2 [W ], And the control unit 7 changes Q2, P2, and Y2 so that the indicated value P2 of the pump 53 and the cumulative operation time Y2 are increased (step S226). Further, the number of changes is incremented by 1 (step S228). The controller 7 repeats Steps S216 to S228 until the number of changes reaches NA times. In this case, the instruction value P2 of the pump 53 gradually increases so as to adapt to the degree of clogging of the filter 51. As a result, the cathode flow rate per unit time supplied to the stack 1 is reduced to reduce the power generation output of the stack 1, thereby delaying the progress of clogging of the filter 51. That is, the power generation operation is continued while the power generation output of the stack 1 is reduced, and the remaining life of the filter 51 is extended. In this way, the control unit 7 maintains the indicated value of the pump 53 until the maximum power generation output of the stack 1 becomes equal to or lower than Q3 [W] (Q3 <Q2 <Q1). If the maximum power generation output of stack 1 is as low as Q3 [W] or less (YES in step S234), the power generation output is considerably reduced and clogging of filter 51 has progressed considerably, and the power generation stoppage determination of stack 1 (step S294) is performed.

  Here, although the cumulative operation time from the previous maintenance is Y1 or more and less than Y2 (Y2> Y1) (NO in step S224), the maximum power generation output of the stack 1 is Q2 [W] or less. Because it is low (Q3 <Q2 <Q1), it is estimated that the filter 51 is clogged considerably. For this reason, the control part 7 implements the notification 3 which alert | reports that to a user or a maintenance person (step S290). Accordingly, it is preferable that maintenance of the filter 51 is performed. Thereafter, the control unit 7 generates power while maintaining the indicated value of the pump 53 until the filter 51 is further clogged.

  And the control part 7 determines whether the instruction | indication value of the pump 53 is more than P12 (P12> P2) and continues more than time T12min (step S292). If NO in step S292, the filter 51 is clogged. Therefore, the control unit 7 maintains the indicated value of the pump 53 and continues the power generation operation. If YES in step S292, power generation stoppage determination processing is performed (step S294), the profit / loss of power generation by the system is determined, and if it is a loss, power generation is stopped. If power generation is profitable, continue power generation.

  According to the present embodiment, the accumulated operation times Y1, Y2, times T1, T2, T11, T12, T13, the indicated values P1, P2, P11, P12 of the pump 53, the power generation outputs Q1, Q2, Q3, the number NA Is preferably stored in a predetermined area of the memory 7d by a user, a system installer, a maintenance person, or the like from the setting device 75. However, it may be preset as a fixed value. Since the clogging of the filter 51 is greatly influenced by the installation location of the fuel cell system as compared with the desulfurizer 31 and the water purifier 33, it can be arbitrarily set from the setting device 75 according to the installation location of the system. Meaningful. In particular, it is significant that the cumulative operation time Y1, Y2, etc. can be arbitrarily set from the setting device 75 in accordance with the installation location of the system. Also in this embodiment, as in the embodiment described later, it is determined whether or not the remaining life of the filter 51 can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, and the remaining life of the filter 51 is determined. However, if it can be matched with the next maintenance time of the desulfurizer 31 and the water purifier 33, the remaining life of the filter 51 may be extended so that it can be matched.

(Embodiment 4)
FIG. 7 shows a fourth embodiment. FIG. 7 shows a flowchart of the remaining life extension process executed by the control unit 7. As shown in FIG. 7, the control unit 7 determines whether or not the cumulative operation time is equal to or longer than Y7 (for example, 600 hours, Y7 <Y1, Y2) from the previous maintenance time of the filter 51 (step S402). Further, it is determined whether or not the maximum power generation output of the stack 1 is equal to or greater than Q7 [W] (Q7>Q1; step S404).

  If the indicated value of the pump 53 is P8 (P8 <P1) or more and continues for the time T8min or longer (YES in Step S406), the filter 51 is slightly clogged. If “YES” in the step S406, it is determined whether or not the indicated value of the pump 53 is not less than P9 (P8 <P9) and continues for a time T9min or more (step S408). If “YES” in the step S408, a time ΔT from the time determined as YES in the step S406 to the time determined as YES in the step S408 is obtained (step S410). The control unit 7 estimates the remaining life of the filter 51 based on the difference ΔP between the instruction value P8 of the pump and the instruction value P9 of the pump and the time ΔT (step S).

  Further, the control unit 7 reads the next maintenance time of the desulfurizer 31 and the next maintenance time of the water purifier 33 from a predetermined area of the memory 7d (step S414). Next, it is determined whether or not the remaining life of the filter 51 can be matched with the next maintenance time of the desulfurizer 31 (step S416). Further, it is determined whether or not the remaining life of the filter 51 can be matched with the next maintenance time of the water purifier 33 (step S418). If they can be matched (YES in step S416, YES in step S418), the control unit 7 performs a remaining life extension process for the filter 51 (step S430). The remaining life extension process is exemplified by the remaining life extension process described above, but is not limited to this. In short, the flow rate per unit time of the cathode gas supplied to the stack 1 is reduced to reduce the stack life of the stack 1. Any control that can extend the remaining life of the filter 51 while reducing the power generation output may be used. When the power is insufficient, it is preferable to purchase the insufficient power from the commercial power source 49. If they do not match, the control unit 7 instructs the normal power generation operation, not the remaining life extension process of the filter 51 (step S420), and notifies the user or the maintenance person that the remaining life extension process of the filter 51 is not performed. (Step S422).

  According to the present embodiment, data such as the accumulated operation time Y8, times T8 and T9, and the instruction values P8 and P9 of the pump 53 are stored in the memory 7d from the setting device 75 by the user, system installer, maintenance person, and the like. It is preferable that data can be stored in a predetermined area. Since the clogging of the filter 51 is greatly influenced by the installation location of the fuel cell system as compared with the desulfurizer 31 and the water purifier 33, it can be arbitrarily set from the setting device 75 according to the installation location of the system. It is meaningful. In particular, it is significant that the cumulative operation time Y8 can be arbitrarily set from the setting device 75 according to the installation location of the system.

  (Others) The present invention is not limited to the embodiment described above and shown in the drawings, and can be implemented with appropriate modifications within a range not departing from the gist. For example, the purification unit may be a desulfurizer 31 that purifies the fuel material by reducing the sulfur component of the fuel material of the anode gas. In this case, the maintenance parts other than the desulfurizer 31 include the filter 51 and / or the water purifier 33. In this case, the next maintenance time of maintenance parts (filter 51 and / or water purifier 33) other than the desulfurizer 31 to be subjected to the remaining life extension processing is stored in the area of the memory 7d. In this case, the control unit 7 performs the remaining life extending process for extending the remaining life of the desulfurizer 31 at the next maintenance time of the filter 51 and / or the water purifier 33 which are maintenance parts other than the desulfurizer 31. In order to adjust the next maintenance time of the desulfurizer 31, the flow rate per unit time for transporting the fuel raw material passing through the desulfurizer 31 is decreased to extend the remaining life of the desulfurizer 31. Maintenance time can be delayed. The stack 1 is not limited to a fixed polymer fuel cell, and may be a solid oxide fuel cell or a phosphoric acid fuel cell. The pumps 53, 37, 23, and 42 may be fans, compressors, and blowers as necessary.

  1 is a stack, 10 is an anode, 11 is a cathode, 20 is an anode gas supply passage (anode fluid supply passage), 31 is a desulfurizer (maintenance part), 33 is a water purifier (maintenance part), 35 is a tank, 49 is Commercial power supply, 51 is a filter (purification unit, maintenance parts), 52 is a cathode gas supply passage (cathode fluid supply passage), 53 is a cathode gas pump (conveyance source), 8 is a hot water storage system, 82 is a pump, 7 is a control unit, 7d indicates a memory (storage element), and 75 indicates a setting device.

Claims (5)

A fuel cell that is supplied with an anode fluid and a cathode fluid to generate electric power; a purification unit that purifies the fluid used in the fuel cell and that is regularly or irregularly maintained; a transport source that transports the fluid; A control unit for controlling the conveyance source,
When the deterioration of the purification unit proceeds, the control unit executes a remaining life extension process for reducing the flow rate per unit time of the fluid passing through the purification unit and extending the remaining life of the purification unit. A fuel cell system that delays maintenance time of the purification unit. In claim 1, in addition to the purification unit to be processed to extend the remaining life, comprising maintenance parts that are regularly or irregularly maintained,
The control unit has a storage unit for storing a next maintenance time of the maintenance part to be subjected to the remaining life extension process,
In the remaining life extension process, the control unit adjusts the flow rate per unit time of the fluid passing through the purification unit so that the next maintenance time of the purification part is matched with the next maintenance time of the maintenance part. A fuel cell system that delays maintenance time of the purifying unit by executing a remaining life extending process for extending the remaining life of the purifying unit by lowering the remaining life.   3. The fuel cell system according to claim 1, further comprising a setting device that sets a threshold value for executing the remaining life extension process.   4. The purification unit according to claim 1, wherein the purification unit includes a filter that reduces the dust contained in the cathode fluid to purify the cathode fluid, a desulfurizer that desulfurizes a fuel raw material of the anode fluid, and the system. The fuel cell system which is at least one of the water purifiers which purify the water.   5. The fuel cell system according to claim 4, wherein the maintenance component is at least one of the filter, the desulfurizer, and the purifier of the water purifier.

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