JP6167280B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell that generates power using an oxidant gas and a fuel gas.

  A fuel cell is a device that generates water and heat by generating electricity through an electrochemical reaction between a fuel gas containing hydrogen and an oxidant gas containing oxygen. Fuel cells are attracting attention because of their high power generation efficiency because they can be directly taken out as electrical energy without converting the chemical energy of fuel into mechanical energy, but it cannot be said that the cost has been reduced sufficiently. Along with the popularization of battery systems, it has become a major issue to reduce costs.

  A fuel cell system including a fuel cell that is a power generation unit that generates power by reacting a fuel gas and an oxidant gas has a first circulation path for circulating cooling water for cooling the fuel cell in order to perform stable power generation. And a cooling water tank for storing cooling water. And a fuel cell power generator comprising a condensate water tank for recovering the produced water obtained by condensing water vapor contained in the off-oxidant gas that is the oxidant gas discharged from the fuel cell main body and the off-combustion gas discharged from the burner Known (see, for example, Patent Document 1 and Patent Document 2).

  Patent Document 1 has a water filling mode in which water necessary for a fuel cell system is automatically filled with water from the outside of the fuel cell system (hereinafter referred to as “automatic water supply”), so that a tank for storing water is troublesome. It is possible to add water without applying water. Patent Document 2 discloses that the water quality of water supplied to the cooling water tank is adjusted by the water treatment means at the start and / or end of the operation of the fuel cell system, and then supplied to the cooling water tank. It is configured to maintain the water quality.

JP 2006-107893 A JP 2002-141095 A

  In a conventional fuel cell system, when operating when the fuel cell system is installed (for example, when operating for the first time after installation or when operating after draining water for maintenance, etc.), it is necessary for the operation of the fuel cell system. It was necessary to supply water to the cooling water tank (hereinafter referred to as “water filling operation”). Thus, conventionally, from the outside of the fuel cell system, it has been performed by city water tap pressure and automatic water supply using city water, the viewpoint of simplifying the configuration of the fuel cell system and realizing stable operation There was room for improvement.

  As described above, the present invention simplifies the configuration of the fuel cell system when manually supplying water to the fuel cell system, and can save space and power, improving workability, An object is to provide a power generation system that can be stably operated without impairing reliability.

In the configuration of the conventional fuel cell system, the inventors of the present application need to seal the city water with a stop valve (electromagnetic valve) after the automatic water supply in the automatic water supply using the city water tap pressure. It was found that there was room for improvement in terms of cost increase, simplification of configuration, space saving, and power saving.

  On the other hand, it is possible to eliminate the shut-off valve and minimize the purifier by supplying the water necessary for the operation of the fuel cell system by hand (hereinafter referred to as “manual water supply”). become.

  Therefore, for example, a method of performing manual water supply from a condensed water tank can be considered. However, since it is necessary to store the water required for water filling operation in the condensate tank and then supply it to the cooling water tank, it is not possible to supply water that exceeds the capacity of the condensate water tank, and the number of water supply increases. The time required for water filling operation of the system became long, and there was a problem from the viewpoint of improving workability.

  Therefore, by using purified water as the water necessary for the operation of the fuel cell system, the water that was conventionally supplied from the condensed water tank to the cooling water tank via the purifier is directly supplied to the cooling water tank. It is possible to reduce the number of times of water supply during water filling operation and improve workability such as time for water filling operation.

  However, in a fuel cell system configured on the assumption that purified water is supplied, the water supplied to the fuel cell system should be referred to as unpurified tap water (hereinafter referred to as “city water” as appropriate). Is misused, water with high conductivity is supplied from the cooling water tank into the cooling water path of the fuel cell. Moreover, in the fuel cell system described in Patent Document 2, water is purified by an ion removal filter when the fuel cell system starts up and / or ends. However, in this method, since the conductive ions are dissolved from the heat exchanger after the fuel cell system has been operated for a predetermined time, the cooling water is purified by the ion removal filter at the start of operation and / or at the end of the operation. Therefore, it is assumed that the purification of the cooling water is executed after operating for a predetermined time. Therefore, the cooling water is not purified in the trial operation process after manual water supply. Therefore, in manual water supply to the cooling water tank, water with high conductivity is introduced into the cooling water path of the fuel cell, and the conduction of the water causes a short circuit in the cooling water path of the fuel cell, resulting in a decrease in power generation. The present inventors have found that this problem occurs.

In order to solve the above-described conventional problems, a fuel cell system according to the present invention circulates a fuel cell that generates power using an oxidant gas and a fuel gas, and cooling water that absorbs heat generated by the fuel cell. A first circulation path, a cooling water tank disposed on the first circulation path and configured to be supplied with cooling water via a water supply unit ; a fuel cell disposed at a position lower than the cooling water tank; Condensation for storing water contained in at least one of the off-fuel gas that is discharged from the fuel cell and the off-oxidant gas that is the oxidant gas discharged from the fuel cell
A water tank, a second circulation path configured to return the cooling water discharged from the cooling water tank to the cooling water tank via the condensed water tank, and a second circulation path disposed on the second circulation path. A water purifier for purifying the cooling water flowing through the second circulation path, a first water circulation pump that circulates the cooling water in the second circulation path, and a cooling water tank and a condensed water tank in communication with each other. A cooling water drainage path for returning the cooling water of the tank to the condensate water tank, and a controller for executing a purification step for purifying the cooling water with the water purifier , wherein the controller supplies water to the cooling water tank. After the process is started and water supply to the cooling water tank is started, the first water circulation pump is operated, the cooling water in the condensed water tank is circulated through the water purifier, and then the second circulation path is set. To the cooling water tank, and the cooling water tank To perform the purification step of returning the cooling water in the click to the condensed water tank via the cooling water discharge passage, a fuel cell system.

  According to the fuel cell system of the present invention, when performing manual water supply to the fuel cell system, even when city water is supplied, the cooling water can be purified before power generation of the fuel cell. It is possible to improve and improve the stability of operation.

1 is a block diagram schematically showing a schematic configuration of a fuel cell system according to Embodiment 1 of the present invention. The flowchart which shows the sequence of the fuel cell system in Embodiment 1 of this invention. The flowchart which shows the sequence of the fuel cell system in the modification 1 of Embodiment 1 of this invention. FIG. 2 is a block diagram schematically showing a schematic configuration of a fuel cell system according to Modification 2 of Embodiment 1. Flowchart showing the sequence of the fuel cell system in the second modification of the first embodiment. Flowchart showing the sequence of the fuel cell system in Modification 3 of Embodiment 1. Flowchart showing the sequence of the fuel cell system in Modification 4 of Embodiment 1.

A first aspect of the invention is a fuel cell that generates power using an oxidant gas and a fuel gas, a first circulation path through which cooling water that absorbs heat generated by the fuel cell circulates, and a first circulation path. A cooling water tank configured to be supplied with cooling water through a water supply unit , an off-fuel gas that is disposed at a position lower than the cooling water tank and is discharged from the fuel cell, and A condensed water tank that stores moisture contained in at least one off-oxidant gas that is an oxidant gas discharged from the fuel cell, and cooling water discharged from the cooling water tank is cooled through the condensed water tank. A second circulation path configured to return to the water tank; a water purifier disposed on the second circulation path for purifying cooling water flowing through the second circulation path; and disposed on the second circulation path. Cooling to the second circulation path A first water circulation pump for circulating a cooling water tank the condensed water tank is communicated with a cooling water drain passage for returning the cooling water in the cooling water tank to the condensation water tank, a purifying step of purifying cooling water in the water purifier A controller that executes the first water circulation pump during the water supply process in which water is supplied to the cooling water tank and after the water supply to the cooling water tank is started , After circulating the cooling water in the condensed water tank through the water purifier, the cooling water is supplied to the cooling water tank via the second circulation path, and the cooling water in the cooling water tank is supplied to the condensed water tank via the cooling water drainage path. The purification step to return to is performed. With this configuration, even when city water is supplied to the cooling water tank during manual water supply, the city water can be purified by a purifier before generating power in the fuel cell. It becomes possible to prevent a short circuit in the cooling water passage of the battery.
Also, with this configuration, the cooling water discharged from the cooling water tank during manual water supply is also supplied to the condensed water tank, and the cooling water supplied to the condensed water tank returns to the cooling water tank via the water purifier. Therefore, the conventional process of supplying water from the condensed water tank to the cooling water tank becomes unnecessary, and the number of times of water supply during manual water supply can be reduced.
Also, with this configuration, when supplying cooling water to the cooling water tank during manual water supply, cooling water can be supplied from the cooling water tank to the condensed water tank by natural fall using gravity, and a new supply pump can be installed. It becomes possible to supply cooling water to the condensed water tank without adding.

In a second aspect based on the first aspect , the controller is stored in the cooling water tank, the condensed water tank, the second circulation path and the cooling water drainage path when manually supplying the cooling water to the cooling water tank. A manual water storage amount that is a water storage amount is stored in advance, and in the purification step, the first water circulation pump is controlled so that more cooling water than the manual water storage amount passes through the water purifier. With this configuration, even when city water is supplied via the cooling water tank during manual water supply, the city water can be purified without exceeding the amount of stored water, and the conductivity in the cooling water path of the fuel cell can be reduced. In addition, it is possible to prevent carbonization in the cooling water passage of the fuel cell and to minimize the water filling operation time during manual water supply.

According to a third aspect of the present invention, in the first or second aspect of the present invention , a conductivity measuring device for measuring the conductivity of the cooling water is provided, and the controller has a predetermined conductivity value measured by the conductivity measuring device. If it is greater than or equal to the first threshold, control is performed to execute the purification step. With this configuration, it is possible to control so that the purification step can be executed only when the cooling water supplied by manual water supply is city water with high conductivity, and the water filling operation time during manual water supply can be minimized.

4th invention is equipped with the 2nd water circulation pump arrange | positioned on the 1st circulation path in 1st- 3rd invention, and a controller purifies before operating a 2nd water circulation pump after manual water supply operation | movement. when complete the step, to complete the purification step. With this configuration, even when the cooling water supplied by manual water supply is city water, after the purification of the city water is completed, the second water circulation pump is operated, so that the conduction in the cooling water path of the fuel cell It is possible to prevent a short circuit in the coolant passage of the fuel cell.
A fifth invention includes the second water circulation pump disposed on the first circulation path in the third invention, and the controller purifies the electrical conductivity when the conductivity value falls below a first threshold value set in advance. Complete the step. With this configuration, even when the cooling water supplied by manual water supply is city water, if the conductivity is lowered below a predetermined first threshold value, the fuel cell is operated by an unnecessary purification operation by completing the purification step. It is possible to prevent a reduction in system operation time.

A sixth invention is the invention according to any one of the first to third inventions, wherein the controller is at least one of a case where the fuel cell system is installed and performing a test operation, and a case where a test operation after maintenance is performed. If so, control is performed to perform the purification step. With this configuration, the fuel cell system performs the purification step only when the fuel cell system is installed and a test operation is performed and when a test operation after maintenance is performed, and the operation time of the fuel cell system due to an unnecessary purification operation Can be prevented.
According to a seventh aspect of the invention, there is provided a fuel cell that generates power using an oxidant gas and a fuel gas, a first circulation path through which cooling water that absorbs heat generated by the fuel cell circulates, and a first circulation path A cooling water tank configured to be supplied with cooling water via a water supply unit, a first water circulation pump disposed at a position lower than the cooling water tank, and a cooling water drainage path from the cooling water tank. The cooling water discharged via the second circulation path configured to return to the cooling water tank via the first water circulation pump, and the cooling water arranged on the second circulation path and flowing through the second circulation path A water purifier that purifies the cooling water and a controller that executes a purification step for purifying the cooling water with the water purifier, and the controller is in a water supply process in which manual water is supplied to the cooling water tank, and After manual water supply to the cooling water tank is started The first water circulation pump is operated, and the cooling water discharged from the cooling water tank via the cooling water drainage path is circulated through the water purifier via the first water circulation pump and then cooled via the second circulation path. A purification step is performed to return to the water tank. With this configuration, even when city water is supplied to the cooling water tank during manual water supply, the city water can be purified by a purifier before generating power in the fuel cell. It becomes possible to prevent a short circuit in the cooling water passage of the battery.

  Hereinafter, embodiments of the present invention will be specifically exemplified. In all the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted. Further, in all the drawings, only components necessary for explaining the present invention are extracted and illustrated, and other components are not illustrated. Furthermore, the present invention is not limited to the following embodiment.

(Embodiment 1)
FIG. 1 is a block diagram schematically showing a schematic configuration of a fuel cell system according to Embodiment 1 of the present invention.

  As shown in FIG. 1, a fuel cell system 100 according to Embodiment 1 of the present invention includes a hydrogen generator 1, a fuel cell 5, a first circulation path 8, a second water circulation pump 10, a cooling water tank 11, and condensed water. A tank 12, a first water circulation pump 13, a purifier 14, a second circulation path 15, a water supply unit 23, a water supply path 24, and a controller 101 are provided. In addition, a fuel cell device including a hydrogen generator 1 and a fuel cell 5 is disposed.

  The hydrogen generator 1 has a reformer 1a and a combustor 1b for heating the reformer. An off-fuel gas path 4 b that connects the fuel cell 5 and the combustor 1 b is connected to the combustor 1 b of the hydrogen generator 1. The combustor 1b burns off-fuel gas that is fuel gas discharged from the fuel cell 5 via the off-fuel gas path 4b to generate combustion exhaust gas. In addition, you may directly form the path | route for supplying a raw material separately in the combustor 1b.

  Here, the raw material means a gas or liquid having at least hydrocarbon as a component, for example, natural gas, coal, petroleum, fossil fuel such as methane hydrate, and city gas.

  The combustion exhaust gas generated by the combustor 1 b of the hydrogen generator 1 is heated to the reformer 1 a and then discharged to the off-combustion gas path 9, and from the off-combustion gas path 9 through the exhaust unit 22, the fuel cell system 100. Discharged outside.

A raw material supply unit 2 and a water supply unit 3 are connected to the reformer 1 a of the hydrogen generator 1. The raw material supply unit 2 is configured to supply a raw material gas, which is a gaseous raw material, to the reformer 1a while adjusting the flow rate. As the raw material supply part 2, for example, a flow rate adjusting valve and a pump may be configured, or a flow rate adjustable pump may be configured.

  The water supply device 3 is provided with a water supply device (not shown) for supplying condensed water stored in the condensed water tank 12 to the reformer 1a. The water supply device 3 may be in any form as long as it is configured to supply condensed water while adjusting the flow rate to the reformer 1a. It may be comprised, and may be comprised with the pump which can adjust flow volume. Since the condensed water stored in the condensed water tank 12 contains some impurities, the condensed water is purified through the purifier 14 provided with an ion exchange resin and supplied to the water supplier 3.

  The reformer 1a of the hydrogen generator 1 is configured to generate a fuel gas containing hydrogen by causing a reforming reaction between the raw material gas and water. The fuel gas generated by the reformer 1a is supplied to the anode (not shown) of the fuel cell 5 through the fuel gas supply path 4a.

  The fuel cell 5 has an anode and a cathode (not shown). As the fuel cell 5, various fuel cells such as a polymer electrolyte fuel cell, a direct internal reforming solid oxide fuel cell, and an indirect internal reforming solid oxide fuel cell can be used.

  In the first embodiment, the hydrogen generator 1 and the fuel cell 5 are separately configured. However, the present invention is not limited to this, and the hydrogen generator 1 and the fuel cell 5 are not limited to this. The fuel cell 5 may be integrally formed. In this case, the hydrogen generator 1 and the fuel cell 5 are configured as one unit covered with a common heat insulating material, and the combustor 1b of the hydrogen generator 1 heats not only the reformer 1a but also the fuel cell 5. To do. Moreover, in the direct internal reforming solid oxide fuel cell, the anode of the fuel cell 5 has the function of the reformer 1a, so that the anode of the fuel cell 5 and the reformer 1a of the hydrogen generator 1 are connected. You may be comprised integrally. Furthermore, since the structure of the fuel cell 5 is the same as that of a general fuel cell, its detailed description is omitted.

  An oxidant gas containing oxygen (air is used in the present embodiment) is supplied from the blower 6 through the oxidant gas path 7 to the cathode of the fuel cell 5. Then, the fuel gas supplied to the anode and the oxidant gas supplied to the cathode react to generate water, and electricity and heat are generated. The fuel gas that has not been used in the fuel cell 5 is supplied to the combustor 1b of the hydrogen generator 1 through the off-fuel gas path 4b as off-fuel gas. Further, oxidant gas (not shown) that has not been used in the fuel cell 5 is discharged out of the fuel cell system 100 via the exhaust air path and the exhaust part 22.

  The generated electricity is supplied to an external power load (for example, home electrical equipment) by a power regulator (not shown). The generated heat is recovered by the cooling water flowing through the first circulation path 8.

  In the first embodiment, the exhaust heat recovery water path 27 is provided so that a part thereof is located outside the fuel cell system 100. In the exhaust heat recovery water path 27, an exhaust gas heat exchanger 16, an exhaust air heat exchanger 17, and a cooling water heat exchanger 18 are provided in this order. Then, the first heat medium in the exhaust heat recovery water passage 27 flows through each heat exchanger while exchanging heat with the other heat medium. As the first heat medium, water or an antifreeze liquid (for example, an ethylene glycol-containing liquid) can be used.

The exhaust gas heat exchanger 16 is provided so as to contact the exhaust heat recovery water path 27 and the off combustion gas path 9, and the first heat medium and the off combustion gas path 9 flowing through the exhaust heat recovery water path 27. It is configured to exchange heat with the off-combustion gas flowing therethrough. In addition, by exchanging heat with the first heat medium in the exhaust gas heat exchanger 16, the water vapor in the off-combustion gas is condensed to generate condensed water. The generated condensed water is collected in the condensed water tank 12 through the exhaust gas condensed water path 19. The off-combustion gas after the condensed water is recovered is discharged out of the fuel cell system 100 through the exhaust unit 22. With this configuration, only the condensed water in the off-combustion gas is collected in the condensed water tank 12.

  The exhaust air heat exchanger 17 is provided so as to contact the exhaust heat recovery water path 27 and the exhaust air path (not shown), and the first heat medium flowing through the exhaust heat recovery water path 27 Heat is exchanged with the off-oxidant gas flowing through the exhaust air flow path. In addition, by exchanging heat with the first heat medium in the exhaust air heat exchanger 17, the water vapor in the off-oxidant gas is condensed and condensed water is generated. The generated condensed water is collected in the condensed water tank 12 through the exhaust air condensed water path 20. The off-oxidant gas after the condensed water is recovered is discharged out of the fuel cell system 100 through the exhaust unit 22. With this configuration, only the condensed water in the off-oxidant gas is collected in the condensed water tank 12.

  The cooling water heat exchanger 18 is provided so as to contact the exhaust heat recovery water path 27 and the first circulation path 8, and the first heat medium and the first circulation path 8 flowing through the exhaust heat recovery water path 27. It is configured to exchange heat with the cooling water flowing therethrough. The second water circulation pump 10 is disposed on the first circulation path 8 and circulates cooling water between the fuel cell 5 and the cooling water tank 11. With this configuration, the heat generated by the fuel cell 5 can be recovered in the exhaust heat recovery water path 27.

  Next, the structure of the cooling water tank 11, the condensed water tank 12, and the water supply part 23 which are the characterizing parts of this invention is demonstrated.

  The cooling water tank 11 is configured to be supplied with cooling water via the water supply unit 23 and the water supply path 24, and the cooling water tank 11 and the condensed water tank 12 communicate with each other via the cooling water drain path 25. doing. Further, the cooling water tank 11 and the water supply unit 23 are arranged at a higher position in the vertical direction than the condensed water tank 12. With this configuration, the cooling water supplied from the water supply unit 23 is supplied to the cooling water tank 11 and then supplied to the condensed water tank 12 through the cooling water drainage path 25. When the cooling water supplied to the condensed water tank 12 is excessive, it is discharged out of the fuel cell system 100 via the drainage path 26. In addition, although the water supply part 23 illustrates the form comprised by the funnel type, as long as it can supply water, what kind of aspect may be sufficient as it.

  Further, the condensed water tank 12 is communicated with the second circulation path 15 so that the cooling water discharged from the cooling water tank 11 returns to the cooling water tank 11, and the purifier 14 is placed on the second circulation path 15. The 1st water circulation pump 13 which is arrange | positioned and circulates cooling water is provided. With this configuration, the cooling water discharged from the cooling water tank 11 can be returned to the cooling water tank 11 after passing through the purifier 14, and the cooling water tank 11 and the condensed water tank 12 Both the cooling waters can be purified by the purifier 14.

  The controller 101 may be in any form as long as it is a device that controls each device constituting the fuel cell system 100. The controller 101 includes an arithmetic processing unit exemplified by a microprocessor, a CPU, and the like, and a storage unit configured by a memory or the like that stores a program for executing each control operation. Then, in the controller 101, the arithmetic processing unit reads out a predetermined control program stored in the storage unit and executes it to process the information, and the fuel cell system 100 including these controls. Various controls are performed.

Note that the controller 101 is not only configured as a single controller, but also configured as a controller group in which a plurality of controllers cooperate to execute control of the fuel cell system 100. I do not care. The controller 101 may be composed of a microcomputer, and an MPU
, PLC (Programmable Logic Controller), logic circuit, etc.
[Operation of fuel cell system]
Next, the operation of the fuel cell system 100 according to Embodiment 1 will be described with reference to FIGS. The power generation operation in the fuel cell system 100 is performed in the same manner as the power generation operation of a general fuel cell system, and thus detailed description thereof is omitted.

  FIG. 2 is a flowchart schematically showing the cooling water purification operation of the fuel cell system according to the first embodiment.

As shown in FIG. 2, the controller 101 confirms whether or not a test operation command for the fuel cell system 100 has been input (step S101). Here, as a case where a test operation command for the fuel cell system 100 is input, for example, an installer of the fuel cell system 100 operates a remote controller (not shown) to activate the test operation after the fuel cell system 100 is installed. The case where it instruct | indicates, the case where the user of the fuel cell system 100 instruct | indicates to operate the test run of the fuel cell system 100 after a long absence, etc. are mentioned. In the flowchart showing the cooling water purification operation of the fuel cell system according to the first embodiment, an example in which it is confirmed whether or not a test operation command for the fuel cell system has been input (step S101) is illustrated. The opening / closing detector of the unit 23 may detect the opening / closing of the water supply unit 23 and confirm whether or not the trial operation command of the fuel cell system 100 has been input.
Moreover, when operating trial run in manual water supply, the case where the water supply process by manual water supply is completed previously before a driving | running is mentioned.

  When the test operation command for the fuel cell system 100 is not input (No in Step S101), the controller 101 repeats Step S101 until the test operation command for the fuel cell system 100 is input. On the other hand, when the test operation command for the fuel cell system 100 is input (Yes in Step S101), the controller 101 proceeds to Step S102.

  In step S102, the controller 101 operates the first water circulation pump. Thus, the cooling water in the condensed water tank 12 is supplied to the cooling water tank 11 after flowing through the purifier 14. In addition, the cooling water supplied from the condensed water tank 12 to the cooling water tank 11 returns to the condensed water tank 12 through a cooling water drainage path 25 that connects the cooling water tank 11 and the condensed water tank 12. .

  In step S103, a storage amount of cooling water that can be supplied by manual water supply (hereinafter referred to as “manual storage amount”) is stored in advance, and it is determined whether or not the amount of water that has passed through the purifier 14 exceeds the manual storage amount. . Specifically, the manual water storage amount is an amount that fills the supplied cooling water tank 11, the condensed water tank 12, and each cooling water supply path with the cooling water. Therefore, it is determined from the cooling water supply capability of the first water circulation pump 13 that supplies cooling water to the purifier 14 whether or not the cooling water that has passed through the purifier 14 is equal to or greater than the manual water storage amount.

  When the controller 101 passes the purifier 14 more than the manual water storage amount (Yes in step S103), it can be considered that all city water supplied by manual water supply has been purified, so this program is finish.

  Thus, in the fuel cell system 100 according to the first embodiment, both the cooling water tank 11 and the condensed water tank 12 are cooled even when city water is supplied to the cooling water supplied by manual water supply. Water can be purified before the fuel cell system 100 is started.

For this reason, in the fuel cell system 100 according to the first embodiment, only the purified cooling water is supplied to the fuel cell 5, and therefore, in the cooling water passage of the fuel cell due to the conduction in the cooling water passage of the fuel cell. It is possible to prevent the short circuit, and it is possible to stably operate without impairing the reliability of the fuel cell system 100.
[Modification 1]
Next, Modification Example 1 of the fuel cell system 100 according to Embodiment 1 will be described.

  FIG. 3 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 of the first modification in the first embodiment.

  The basic configuration of the fuel cell system 100 according to the first modification is the same as that of the fuel cell system 100 according to Embodiment 1, except that the operation of the second water circulation pump 10 is added to the flowchart.

  As shown in FIG. 3, the controller 101 confirms whether or not a test operation command for the fuel cell system 100 has been input (step S201). Here, as a case where a test operation command for the fuel cell system 100 is input, for example, an installer of the fuel cell system 100 operates a remote controller (not shown) to activate the test operation after the fuel cell system 100 is installed. The case where it instruct | indicates, the case where the user of the fuel cell system 100 instruct | indicates to operate the test run of the fuel cell system 100 after a long absence, etc. are mentioned. Moreover, when operating trial run in manual water supply, the case where the water supply process by manual water supply is completed previously before trial run etc. is mentioned.

  When the test operation command for the fuel cell system 100 is not input (No in step S201), the controller 101 repeats step S201 until the test operation command for the fuel cell system 100 is input. On the other hand, when the test operation command for the fuel cell system 100 is input (Yes in Step S201), the controller 101 proceeds to Step S202.

  In step S202, the controller 101 operates the first water circulation pump. Thus, the cooling water in the condensed water tank 12 is supplied to the cooling water tank 11 after flowing through the purifier 14. In addition, the cooling water supplied from the condensed water tank 12 to the cooling water tank 11 returns to the condensed water tank 12 through a cooling water drainage path 25 that connects the cooling water tank 11 and the condensed water tank 12. .

  In step S203, the storage amount of the cooling water supplied by manual water supply is stored in advance, and it is determined whether or not the purifier 14 has passed beyond the manual storage amount. Specifically, the manual water storage amount is an amount that fills the supplied cooling water tank 11, the condensed water tank 12, and each cooling water supply path with the cooling water. Therefore, it is determined from the cooling water supply capability of the first water circulation pump 13 that supplies cooling water to the purifier 14 whether or not the cooling water that has passed through the purifier 14 is equal to or greater than the manual water storage amount.

  When the controller 101 passes through the purifier 14 more than the amount of manual water storage (Yes in step S203), it can be considered that all city water supplied by manual water supply has been purified, so the process proceeds to step S204. move on. On the other hand, when not passing through the purifier 14 more than the amount of manual water storage (No in step S203), the city water supplied by manual water supply has not been completely purified, and thus step S203 is repeated.

  In step S204, the controller 101 operates the second water circulation pump 10. As a result, the purified cooling water that has passed through the purifier 14 is supplied to the fuel cell 5 via the first circulation path 8, and the program ends.

Thus, in the first modification of the fuel cell system 100 according to the first embodiment, even when city water is supplied to the cooling water supplied by manual water supply, after the cooling water is purified by the purifier 14, The cooling water can be supplied to the fuel cell 5.

For this reason, in the first modification of the fuel cell system 100 according to the first embodiment, only the purified cooling water is supplied to the fuel cell 5, so that the conductivity of the fuel cell is reduced by the conduction in the cooling water path of the fuel cell. It is possible to prevent a short circuit in the cooling water passage, and the fuel cell system 100 can be stably operated without impairing the reliability of the fuel cell system 100.
[Modification 2]
Next, Modification Example 2 of the fuel cell system 100 according to Embodiment 1 will be described.

  FIG. 4 is a schematic diagram showing a schematic configuration of Modification 2 of the fuel cell system 100 according to Embodiment 1. As shown in FIG.

  As shown in FIG. 4, the basic configuration of the fuel cell system 100 of the second modification is the same as that of the fuel cell system 100 according to the first embodiment, but the conductivity of water is set in the cooling water tank 11. A conductivity measuring device 21 for measuring is provided, and the conductivity measuring device 21 is different in that it is configured to output the detected conductivity to the controller 101.

  FIG. 5 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 according to the second modification of the first embodiment.

  As shown in FIG. 5, the controller 101 confirms whether or not a test operation command for the fuel cell system 100 has been input (step S301). Here, as a case where a test operation command for the fuel cell system 100 is input, for example, an installer of the fuel cell system 100 operates a remote controller (not shown) to activate the test operation after the fuel cell system 100 is installed. The case where it instruct | indicates, the case where the user of the fuel cell system 100 instruct | indicates to operate the test run of the fuel cell system 100 after a long absence, etc. are mentioned. Moreover, when operating trial run in manual water supply, the case where the water supply process by manual water supply is completed previously before trial run etc. is mentioned.

  When the test operation command for the fuel cell system 100 is not input (No in step S301), the controller 101 repeats step S301 until the test operation command for the fuel cell system 100 is input. On the other hand, when the test operation command for the fuel cell system 100 is input (Yes in Step S301), the controller 101 proceeds to Step S302.

  In step S302, it is determined whether or not the conductivity measured by the conductivity measuring device 21 is equal to or greater than a predetermined first threshold value. Specifically, the conductivity measuring device 21 determines whether or not the supply water supplied by manual water supply is city water. Therefore, the conductivity threshold is about 100 which is the conductivity of general tap water. A value of ˜200 μS / cm or less is set.

  When the threshold value of the conductivity measurement value is equal to or lower than the first threshold value (No in step S302), the controller 101 can consider that the city water is not supplied into the cooling water tank 11, so this program Exit. On the other hand, if the threshold value of the conductivity measurement value is equal to or greater than the first threshold value (Yes in step S302), the controller 101 proceeds to step S303.

  In step S303, the controller 101 operates the first water circulation pump. Thus, the cooling water in the condensed water tank 12 is supplied to the cooling water tank 11 after flowing through the purifier 14. In addition, the cooling water supplied from the condensed water tank 12 to the cooling water tank 11 returns to the condensed water tank 12 through a cooling water drainage path 25 that connects the cooling water tank 11 and the condensed water tank 12. .

  In step S304, the storage amount of the cooling water supplied by manual water supply is stored in advance, and it is determined whether or not the purifier 14 has passed beyond the manual storage amount. Specifically, the manual water storage amount is an amount that fills the supplied cooling water tank 11, the condensed water tank 12, and each cooling water supply path with the cooling water. Therefore, it is determined from the cooling water supply capability of the first water circulation pump 13 that supplies cooling water to the purifier 14 whether or not the cooling water that has passed through the purifier 14 is equal to or greater than the manual water storage amount.

  When the controller 101 passes through the purifier 14 more than the manual water storage amount (Yes in step S304), it can be considered that all city water supplied by manual water supply has been purified, so the process proceeds to step S305. move on. On the other hand, if the purifier 14 is not passed beyond the manual water storage amount (No in step S304), the city water supplied by manual water supply has not been completely purified, and step S303 is repeated.

  In step S305, the controller 101 operates the second water circulation pump 10. As a result, the purified cooling water that has passed through the purifier 14 is supplied to the fuel cell 5 via the first circulation path 8, and the program ends.

  Thus, in the fuel cell system 100 according to the second modification of the first embodiment, whether or not city water is supplied with the conductivity value measured by the conductivity measuring device 21 during the trial operation of the fuel cell system 100. Even if city water is supplied, the cooling water can be supplied to the fuel cell 5 after the cooling water is purified by the purifier 14.

  For this reason, in the fuel cell system 100 according to the second modification of the first embodiment, only the purified cooling water is supplied to the fuel cell 5, so that the conductivity of the fuel cell is reduced by the conduction in the cooling water path of the fuel cell. It is possible to prevent a short circuit in the cooling water passage, and the fuel cell system 100 can be stably operated without impairing the reliability of the fuel cell system 100.

With the fuel cell system 100 of Modification 2 configured as described above, the water filling operation time at the time of manual water supply is minimized while achieving the same effects as the fuel cell system 100 according to Embodiment 1. It becomes possible.
[Modification 3]
Next, Modification Example 3 of the fuel cell system 100 according to Embodiment 1 will be described.

  FIG. 6 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 of the third modification example in the first embodiment.

  The fuel cell system 100 of the third modification has the same basic configuration as that of the fuel cell system 100 according to the second modification of the first embodiment, except that the operation of the flowchart is changed.

  FIG. 6 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 of the third modification example in the first embodiment.

As shown in FIG. 6, the controller 101 confirms whether or not a test operation command for the fuel cell system 100 has been input (step S401). Here, as a case where a test operation command for the fuel cell system 100 is input, for example, an installer of the fuel cell system 100 operates a remote controller (not shown) to activate the test operation after the fuel cell system 100 is installed. The case where it instruct | indicates, the case where the user of the fuel cell system 100 instruct | indicates to operate the test run of the fuel cell system 100 after a long absence, etc. are mentioned. Moreover, when operating trial run in manual water supply, the case where the water supply process by manual water supply is completed previously before trial run etc. is mentioned.

  If the test operation command for the fuel cell system 100 is not input (No in step S401), the controller 101 repeats step S401 until the test operation command for the fuel cell system 100 is input. On the other hand, when the test operation command for the fuel cell system 100 is input (Yes in Step S401), the controller 101 proceeds to Step S402.

  In step S402, it is determined whether or not the conductivity measured by the conductivity measuring device 21 is equal to or greater than a predetermined first threshold value. Specifically, the conductivity measuring device 21 determines whether or not the supply water supplied by manual water supply is city water. Therefore, the conductivity threshold is about 100 which is the conductivity of general tap water. A value of ˜200 μS / cm or less is set.

  When the threshold value of the measured conductivity value is equal to or lower than the first threshold value (No in step S402), the controller 101 can be regarded that the city water is not supplied into the cooling water tank 11, so this program Exit. On the other hand, if the threshold value of the conductivity measurement value is equal to or greater than the first threshold value (Yes in step S402), the controller 101 proceeds to step S403.

  In step S403, the controller 101 operates the first water circulation pump. Thus, the cooling water in the condensed water tank 12 is supplied to the cooling water tank 11 after flowing through the purifier 14. In addition, the cooling water supplied from the condensed water tank 12 to the cooling water tank 11 returns to the condensed water tank 12 through a cooling water drainage path 25 that connects the cooling water tank 11 and the condensed water tank 12. .

  In step S404, it is determined whether or not the conductivity measured by the conductivity measuring device 21 is equal to or less than a predetermined first threshold value. Specifically, the conductivity measuring device 21 determines whether or not the supply water supplied by manual water supply has been sufficiently purified, and therefore, the conductivity threshold is the conductivity of general tap water. A value of about 100 to 200 μS / cm or less is set.

  When the threshold value of the conductivity measurement value is equal to or lower than the first threshold value (Yes in step S404), the controller 101 can consider that the city water has been sufficiently purified in the cooling water tank 11, Proceed to step S405. On the other hand, if the threshold value of the conductivity measurement value is equal to or greater than the first threshold value (No in step S404), the city water supplied by manual water supply has not been sufficiently purified, and step S403 is repeated.

  In step S405, the controller 101 operates the second water circulation pump 10. As a result, the purified cooling water that has passed through the purifier 14 is supplied to the fuel cell 5 via the first circulation path 8, and the program ends.

  Thus, in the fuel cell system 100 according to the third modification of the first embodiment, whether or not city water is supplied with the conductivity value measured by the conductivity measuring device 21 during the trial operation of the fuel cell system 100. Even if city water is supplied, the cooling water can be supplied to the fuel cell 5 after the cooling water is purified by the purifier 14. Further, it is possible to determine whether or not the cooling water has been sufficiently purified based on the threshold value of the conductivity of the cooling water.

  For this reason, in the fuel cell system 100 according to the third modification of the first embodiment, only the purified cooling water is supplied to the fuel cell 5, and therefore, the fuel cell system is connected by the conduction in the cooling water path of the fuel cell. It is possible to prevent a short circuit in the cooling water passage, and the fuel cell system 100 can be stably operated without impairing the reliability of the fuel cell system 100.

With the fuel cell system 100 of Modification 3 configured as described above, the water filling operation time at the time of manual water supply is minimized while achieving the same effects as the fuel cell system 100 according to Embodiment 1. It becomes possible.
[Modification 4]
Next, Modification 4 of the fuel cell system 100 according to Embodiment 1 will be described.

  FIG. 7 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 according to Modification 4 of Embodiment 1.

  The fuel cell system 100 according to the fourth modification has the same basic configuration as the fuel cell system 100 according to the second modification of the first embodiment, except that the operation of the flowchart is changed.

  FIG. 7 is a flowchart schematically showing the cooling water purification operation of the fuel cell system 100 according to Modification 4 of Embodiment 1.

  As shown in FIG. 7, the controller 101 confirms whether or not water is supplied to the fuel cell system 100 from the outside (step S501). Here, as a case where water is supplied to the fuel cell system 100 from the outside, for example, when the installer of the fuel cell system 100 additionally supplies water from the water supply unit 23 after installing the fuel cell system 100, etc. Can be mentioned.

  In step S501, it is determined whether or not the conductivity measured by the conductivity measuring device 21 is equal to or greater than a predetermined first threshold value. Specifically, the conductivity measuring device 21 determines whether the supply water additionally supplied by manual water supply is city water or not, and therefore, the conductivity threshold is the conductivity of general tap water. A value of about 100 to 200 μS / cm or less is set.

  When the threshold value of the conductivity measurement value is equal to or lower than the first threshold value (No in step S501), the controller 101 can be regarded that the city water is not supplied into the cooling water tank 11, so this program Exit. On the other hand, if the threshold value of the conductivity measurement value is equal to or greater than the first threshold value (Yes in step S501), the controller 101 proceeds to step S502.

  In step S502, the controller 101 operates the first water circulation pump. Thus, the cooling water in the condensed water tank 12 is supplied to the cooling water tank 11 after flowing through the purifier 14. In addition, the cooling water supplied from the condensed water tank 12 to the cooling water tank 11 returns to the condensed water tank 12 through a cooling water drainage path 25 that connects the cooling water tank 11 and the condensed water tank 12. .

  In step S503, it is determined whether or not the conductivity measured by the conductivity measuring device 21 is equal to or less than a predetermined first threshold value. Specifically, the conductivity measuring device 21 determines whether or not the supply water additionally supplied by manual water supply has been sufficiently purified. Therefore, the conductivity threshold value includes the conductivity of general tap water. A value of about 100 to 200 μS / cm or less is set.

  When the threshold value of the conductivity measurement value is equal to or lower than the first threshold value (Yes in step S503), the controller 101 can consider that the city water has been sufficiently purified in the cooling water tank 11, The process proceeds to step S504. On the other hand, if the threshold value of the conductivity measurement value is equal to or greater than the first threshold value (No in step S503), the city water supplied by manual water supply has not been sufficiently purified, and step S502 is repeated.

  In step S504, the controller 101 operates the second water circulation pump 10. As a result, the purified cooling water that has passed through the purifier 14 is supplied to the fuel cell 5 via the first circulation path 8, and the program ends.

  As described above, in the fuel cell system 100 according to the fourth modification of the first embodiment, when water is supplied to the fuel cell system 100 from the outside, the electric conductivity value measured by the conductivity measuring device 21 is used as the city water. Even when city water is supplied, it is possible to supply the cooling water to the fuel cell 5 after purifying the cooling water with the purifier 14. Further, it is possible to determine whether or not the cooling water has been sufficiently purified based on the threshold value of the conductivity of the cooling water.

  For this reason, in the fuel cell system 100 according to the fourth modification of the first embodiment, only the purified cooling water is supplied to the fuel cell 5, and therefore, the fuel cell system 100 It is possible to prevent a short circuit in the cooling water passage, and the fuel cell system 100 can be stably operated without impairing reliability.

  In the fuel cell system 100 of the fourth modification configured as described above, the same operational effects as those of the fuel cell system 100 according to Embodiment 1 can be obtained even in operation after water is supplied from the outside. Is possible.

  The fuel cell system of the present invention is useful in the field of fuel cells because it can operate stably without impairing reliability even when city water is supplied during manual water supply.

DESCRIPTION OF SYMBOLS 1 Hydrogen generator 1a Reformer 1b Combustor 2 Raw material supply part 3 Water supply device 4a Fuel gas supply path 4b Off fuel gas path 5 Fuel cell 6 Blower 7 Oxidant gas path 8 First circulation path 9 Off combustion gas path 10 Second water circulation pump 11 Cooling water tank 12 Condensed water tank 13 First water circulation pump 14 Purifier 15 Second circulation path 16 Exhaust gas heat exchanger 17 Exhaust air heat exchanger 18 Cooling water heat exchanger 19 Exhaust gas condensate path 20 Exhaust air Condensate path 21 Conductivity measuring instrument 22 Exhaust part 23 Water supply part 24 Water supply path 25 Cooling water drainage path 26 Drainage path 27 Waste heat recovery water path 100 Fuel cell system 101 Controller

Claims (7)

A fuel cell that generates power using oxidant gas and fuel gas;
A first circulation path through which cooling water that absorbs heat generated by the fuel cell circulates;
A cooling water tank disposed on the first circulation path and configured to be supplied with cooling water via a water supply unit;
An off-gas at least one of an off-fuel gas, which is a fuel gas discharged from the fuel cell, and an off-oxidant gas, which is an oxidant gas discharged from the fuel cell, is disposed at a position lower than the cooling water tank. A condensed water tank for storing water contained in
A second circulation path configured such that the cooling water discharged from the cooling water tank returns to the cooling water tank via the condensed water tank;
A water purifier disposed on the second circulation path and purifying cooling water flowing through the second circulation path;
A first water circulation pump disposed on the second circulation path and circulating cooling water through the second circulation path;
A cooling water drainage path for communicating the cooling water tank and the condensed water tank and returning the cooling water of the cooling water tank to the condensed water tank;
A controller for performing a purification step of purifying the cooling water with the water purifier ,
The controller is in a water supply process in which water is supplied to the cooling water tank, and after the water supply to the cooling water tank is started , the controller operates the first water circulation pump, and the inside of the condensed water tank After the cooling water is circulated through the water purifier, the cooling water is supplied to the cooling water tank through the second circulation path, and the cooling water in the cooling water tank is supplied to the condensed water through the cooling water drainage path. Causing the purification step to return to the tank ,
Fuel cell system. The controller is
When manually supplying cooling water to the cooling water tank, a manual water storage amount that is stored in the cooling water tank, the condensed water tank, the second circulation path, and the cooling water drainage path is stored in advance. And
In the purification step, the first water circulation pump is controlled so that more cooling water than the manual water storage amount passes through the water purifier.
The fuel cell system according to claim 1 . Equipped with a conductivity meter that measures the conductivity of the cooling water,
The controller is configured to perform the purification step when the conductivity value measured by the conductivity measuring device is equal to or greater than a predetermined first threshold;
The fuel cell system according to claim 1 or 2 . A second water circulation pump disposed on the first circulation path;
Wherein the controller, when to complete the purification step before operating the second water circulation pump after a manual water supply operation, to complete the pre-Symbol purification step,
The fuel cell system according to any one of claims 1 to 3 . A second water circulation pump disposed on the first circulation path;
The controller completes the purification step when a conductivity value falls below the predetermined first threshold;
The fuel cell system according to claim 3. The controller is configured to perform the purification step in at least one of a case where the fuel cell system is installed and a trial operation is performed and a trial operation after maintenance is performed,
The fuel cell system according to any one of claims 1 to 3 . A fuel cell that generates power using oxidant gas and fuel gas;
A first circulation path through which cooling water that absorbs heat generated by the fuel cell circulates;
A cooling water tank disposed on the first circulation path and configured to be supplied with cooling water via a water supply unit;
A first water circulation pump disposed at a position lower than the cooling water tank;
A second circulation path configured to return the cooling water discharged from the cooling water tank via the cooling water drainage path to the cooling water tank via the first water circulation pump;
A water purifier disposed on the second circulation path and purifying cooling water flowing through the second circulation path;
A controller for performing a purification step of purifying the cooling water with the water purifier,
The controller operates the first water circulation pump during a water supply process in which manual water supply is performed to the cooling water tank and after manual water supply to the cooling water tank is started, and the cooling water tank The cooling water discharged from the tank via the cooling water drainage path is circulated through the water purifier via the first water circulation pump, and then returned to the cooling water tank via the second circulation path. A fuel cell system that performs a purification step.