JP2016192282A - Fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve reduction in the apparatus failure probability, and load reduction of apparatus control during steady operation of a fuel cell unit.SOLUTION: A plurality of fuel cell units 2 include a reformer 22 generating fuel gas, a fuel cell 23 of a solid oxide, and a housing 21 for housing the reformer 22 and fuel cell 23. An activation unit 3 is sequentially connected with the plurality of fuel cell units 2 removably, and is used for the startup operation of the fuel cell units 2 connected. At the time of startup operation of the second and subsequent fuel cell units 2, power is supplied to the activation unit 3 or the second and subsequent fuel cell units 2, from a started fuel cell unit 2 that has completed startup operation. After ending startup operation of the fuel cell units 2, the activation unit 3 can be removed therefrom. Consequently, reduction in the apparatus failure probability during steady operation of the fuel cell units 2, and load reduction of apparatus control can be achieved.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a fuel cell system.

  Conventionally, various fuel cell systems that generate power using fuel cells have been proposed. In the fuel cell system of Patent Document 1, the inside of the housing is divided into a module part, a fluid supply part, and an electrical component part. The module unit accommodates a fuel cell module and a combustor that raises the temperature of the fuel cell module. The fluid supply unit includes a fuel gas supply device, an oxidant gas supply device, and a water supply device. A power converter that converts DC power generated in the combustion cell module and a control device that controls the amount of power generated by the fuel cell module are disposed in the electrical component. The fluid supply unit is disposed on the first side surface of the module unit, and the electrical component unit is disposed on the second side surface of the module unit. Thereby, since a fluid supply part and an electrical equipment part comprise the outer wall part of a housing | casing, the high temperature of a fluid supply part and an electrical equipment part is suppressed.

  In the fuel cell systems of Patent Document 2 and Patent Document 3, a self-supporting operation of water used for steam reforming is achieved. Further, in the fuel cell module of Patent Document 4, a self-sustained operation is achieved. In the fuel cell system of Patent Document 5, water self-sustained operation and heat self-sustained operation are promoted. In the fuel cell device of Patent Document 6, a heat exchanger that performs heat exchange between the exhaust gas from the fuel cell and the oxygen-containing gas or fuel supplied to the fuel cell is provided, and the oxygen-containing gas after heat exchange or The power generation efficiency is improved by further heating the fuel.

JP 2008-235108 A JP 2011-210448 A JP 2013-2222577 A JP 2012-238537 A JP2013-62217A JP 2014-10895 A

  By the way, in the fuel cell system of Patent Document 1, the combustor used for raising the temperature of the fuel cell module during start-up operation is connected to the fuel gas supply device via the switching valve and the raw fuel branch passage in the housing. Is done. In addition, the combustor is connected to the oxidant gas supply device through the switching valve and the air branch passage in the housing. In the fuel cell system, the switching valve and the branch passage that are not used during steady operation are also held in the casing.

  As described above, when there are many devices in the fuel cell system, the probability of occurrence of a failure increases, and the operation rate of the fuel cell system may decrease. In addition, when the fuel cell system is in steady operation, it is necessary to monitor owned equipment that is not used, which may increase the control load of the fuel cell system. Furthermore, there is a possibility that the power transmission end power of the fuel cell system may decrease due to standby power of the owned equipment that is not used during steady operation.

  The above problem is the same in the other fuel cell systems described above. For example, in the fuel cell system of Patent Document 2, water self-sustained operation during steady operation is achieved, but water tanks and pumps that supply water that are not used when water self-sustained operation is realized include: Held in the fuel cell system. In order to maintain such a water tank or pump, it is necessary to stop the entire fuel cell system. Further, when the pump or the like fails, the entire fuel cell system is stopped, and the entire fuel cell system is replaced as necessary.

  The present invention has been made in view of the above-described problems, and an object thereof is to realize a reduction in the probability of equipment failure during steady operation of a fuel cell unit and a reduction in equipment control load.

  The invention according to claim 1 is a fuel cell system, which is a reformer that reforms raw fuel to generate fuel gas, and a solid oxide type that generates power using the fuel gas and oxidant gas. A plurality of fuel cell units each including a fuel cell unit, a reformer and a housing for housing the fuel cell, and a plurality of fuel cell units that are sequentially and detachably connected to each other, and starting the connected fuel cell unit An activation unit used for operation, and the activation unit is started from the activated fuel cell units that have completed the activation operation at the time of the activation operation of the second and subsequent fuel cell units among the plurality of fuel cell units. Power is supplied to at least one of the second and subsequent fuel cell units.

  Invention of Claim 2 is the fuel cell system of Claim 1, Comprising: The heat | fever which generate | occur | produces in the said started fuel cell unit at the time of start-up operation of the said 2nd unit or later fuel cell unit, This is used as a heating source for the second and subsequent fuel cell units.

  A third aspect of the present invention is the fuel cell system according to the first or second aspect, further comprising a moving vehicle on which the activation unit is loaded.

  The invention according to claim 4 is the fuel cell system according to any one of claims 1 to 3, wherein the reformer performs steam reforming on the raw fuel, and the start-up unit stores water. And a water supply unit for supplying the water to the reformer, a heating energy supply unit for supplying energy used for heating the interior of the housing, and an activation for supplying a starting material to the reformer And at least two supply units among the material supply unit.

  Invention of Claim 5 is a fuel cell system, Comprising: The reformer which reforms raw fuel and produces | generates fuel gas, The solid oxide form which produces electric power using the said fuel gas and oxidant gas A plurality of fuel cell units each comprising a fuel cell, a reformer and a housing for housing the fuel cell, and removably connected to the plurality of fuel cell units, respectively, and activation of the connected fuel cell unit A plurality of activation units each used for driving.

  In the present invention, it is possible to reduce the probability of equipment failure during steady operation of the fuel cell unit and to reduce equipment control load.

It is a figure which shows the structure of the fuel cell system which concerns on 1st Embodiment. It is a figure which shows the structure of a fuel cell unit and a starting unit. It is a perspective view which shows the connection part of a water supply part and a fuel cell unit. It is a figure which shows the structure of the fuel cell system which concerns on 2nd Embodiment.

  FIG. 1 is a diagram showing a configuration of a fuel cell system 1 according to a first embodiment of the present invention. The fuel cell system 1 includes a plurality of fuel cell units 2, one activation unit 3, and one vehicle 61. The activation unit 3 is loaded on the loading unit of the moving vehicle 61. In the following description, the activation unit 3 and the vehicle 61 are collectively referred to as “activation vehicle 6”.

  Each fuel cell unit 2 is a power generation unit that generates power using a fuel cell. The starting unit 3 is sequentially connected to the plurality of fuel cell units 2 in a detachable manner, and is used for starting operation (so-called cold start) of the connected fuel cell units 2. The start-up operation of the fuel cell unit 2 means changing the state of the fuel cell unit 2 from a stopped state to a steady operation state in which power generation is constantly performed.

  FIG. 2 is a diagram showing a configuration of one fuel cell unit 2 and an activation unit 3 connected to the fuel cell unit 2. The structure of the other fuel cell unit 2 is the same as that of the fuel cell unit 2 shown in FIG. 2, and the connection mode when the start unit 3 is connected is also the same. In FIG. 2, the fuel cell unit 2 and the starting unit 3 are surrounded by broken lines. Moreover, illustration of the vehicle 61 is abbreviate | omitted in FIG.

  The fuel cell unit 2 includes a housing 21, a reformer 22, a fuel cell 23, and a temperature raising unit 24. The reformer 22, the fuel cell 23 and the temperature raising unit 24 are accommodated in the housing 21. The fuel cell unit 2 also includes an impurity removing unit 41, a first heat exchanger 42, a blower 43, a second heat exchanger 44, a condensing unit 45, a water vapor generating unit 46, and an exhaust gas burning unit 47. And a raw fuel supply source 48. The fuel cell unit 2 further includes a battery unit control unit 49 and a power receiving unit 40. The power receiving unit 40 is connected to an external power source (not shown) and the like, and supplies power to each component of the fuel cell unit 2. The battery unit control unit 49 controls each component of the fuel cell unit 2.

  The inner surface of the housing 21 is formed of a heat insulating material. As the housing 21, for example, a metal container whose entire inner surface is covered with a heat insulating material is used. The fuel cell 23 is a solid oxide fuel cell (SOFC), and is, for example, a cell stack in which a plurality of cells (unit cells) (not shown) are stacked. Fuel gas is supplied to the negative electrode (anode) of the fuel cell 23, and oxidant gas is supplied to the positive electrode (cathode). As a result, an electrochemical reaction occurs in the fuel cell 23 to generate power. The electrochemical reaction in the fuel cell 23 is an exothermic reaction, and the generated heat is used for heating the reformer 22 or the like. The power generation by the fuel cell 23 is performed at a high temperature of 600 to 1000 degrees, for example. The fuel gas is, for example, hydrogen gas, and the oxidant gas is, for example, oxygen gas.

  The reformer 22 reforms the raw fuel to generate a reformed gas containing a fuel gas. As the raw fuel, for example, LP gas, city gas, natural gas, kerosene, biogas, bioethanol and the like are used. In the reformer 22, the raw fuel is reformed by, for example, a steam reforming method, a partial oxidation reforming method, an autothermal reforming method, or the like. In the example shown in FIG. 2, the reformer 22 reforms the LP gas as the raw fuel at a high temperature by the steam reforming method to generate a reformed gas containing hydrogen gas as the fuel gas.

  The reformer 22 is connected to the negative electrode of the fuel cell 23 by a fuel gas supply pipe 251. The reformed gas generated by the reformer 22 is supplied to the negative electrode of the fuel cell 23 via the fuel gas supply pipe 251. Negative electrode exhaust gas, which is gas discharged from the negative electrode of the fuel cell 23, is discharged out of the housing 21 through the negative electrode exhaust gas discharge pipe 252 and guided to the exhaust gas combustion unit 47. The negative electrode exhaust gas includes water vapor generated when hydrogen gas, which is a fuel gas, is used for power generation in the fuel cell 23, and unused fuel gas that has not been used for power generation in the fuel cell 23.

  The reformer 22 is connected to a raw fuel supply source 48 disposed outside the housing 21 via a raw fuel supply pipe 261. On the raw fuel supply pipe 261, an impurity removing unit 41 and a first heat exchanger 42 are provided. The impurity removal unit 41 removes impurities (for example, sulfur-based impurities) from the raw fuel supplied from the raw fuel supply source 48 to the reformer 22. In the first heat exchanger 42, the raw fuel supplied to the reformer 22 is preheated using the high temperature negative exhaust gas discharged from the negative electrode of the fuel cell 23 and flowing through the negative exhaust gas exhaust pipe 252.

  The negative electrode exhaust gas that has passed through the first heat exchanger 42 is guided to the condensing unit 45. In the condensing part 45, the water vapor | steam in a negative electrode waste gas is condensed and water is produced | generated. The water generated by the condensing unit 45 is supplied to the water vapor generating unit 46. In the water vapor generation unit 46, water is heated to generate water vapor. The steam generated by the steam generation unit 46 is guided to the raw fuel supply pipe 261 through the water supply pipe 262, and is supplied to the reformer 22 together with the raw fuel that has passed through the impurity removal unit 41, so that the above-described steam is supplied. Used for reforming.

  The positive electrode of the fuel cell 23 is connected to a blower 43 disposed outside the housing 21 by an oxidant gas supply pipe 253. The blower 43 supplies air containing oxygen gas, which is an oxidant gas, to the positive electrode of the fuel cell 23 via the oxidant gas supply pipe 253. A positive exhaust gas that is a gas discharged from the positive electrode of the fuel cell 23 is discharged out of the housing 21 through a positive exhaust gas discharge pipe 254. The positive exhaust gas exhaust pipe 254 passes through the second heat exchanger 44 provided on the oxidant gas supply pipe 253. In the second heat exchanger 44, air supplied to the fuel cell 23 is preheated using the high-temperature positive exhaust gas that is discharged from the positive electrode of the fuel cell 23 and flows through the positive exhaust gas exhaust pipe 254.

  The positive exhaust gas exhaust pipe 254 that has passed through the second heat exchanger 44 joins the negative exhaust gas exhaust pipe 252 at a junction 471 before (that is, upstream) the exhaust gas combustion unit 47. In the exhaust gas combustion section 47, the merged negative electrode exhaust gas and positive electrode exhaust gas are combusted. Thereby, unused fuel gas etc. which are contained in anode exhaust gas are burned. The combustion heat generated in the exhaust gas combustion unit 47 is used for, for example, heating of water in the water vapor generation unit 46 or power generation using a turbine. Further, the exhaust gas combustion part 47 may be provided in the housing 21, and the combustion heat of the exhaust gas combustion part 47 may be used for heating the reformer 22. For example, a catalytic combustor is used as the exhaust gas combustion unit 47.

  In the steady operation of the fuel cell unit 2, as described above, the fuel cell 23 generates power using the fuel gas and the oxidant gas. The heat generated during power generation in the fuel cell 23 is applied to the reformer 22 and used for steam reforming of the raw fuel in the reformer 22. Further, the raw fuel supplied to the reformer 22 is preheated using the negative electrode exhaust gas discharged from the fuel cell 23, and the fuel cell 23 is used using the positive electrode exhaust gas discharged from the fuel cell 23. The air supplied to is preheated. Thereby, in the fuel cell unit 2, the steady operation can be performed without applying the heat required in the system during the steady operation from outside the system. Furthermore, in the fuel cell unit 2, by using the water vapor contained in the negative electrode exhaust gas for the steam reforming performed in the reformer 22, the water required in the system during steady operation is given from outside the system. The steady operation can be performed without any problem. In other words, the fuel cell unit 2 at the time of steady operation can perform a heat independent operation and a water independent operation.

  Next, the starting operation of the fuel cell unit 2 will be described. The startup unit 3 used for the startup operation of the fuel cell unit 2 includes a water supply unit 31, a startup material supply unit 32, a heating energy supply unit 33, a startup power supply unit 34, a startup control unit 35, And an activation unit housing 36 (see FIG. 1). The water supply unit 31, the activation material supply unit 32, the heating energy supply unit 33, the activation power supply unit 34, and the activation control unit 35 are accommodated in the activation unit housing 36. The activation control unit 35 controls the water supply unit 31, the activation material supply unit 32, the heating energy supply unit 33, and the activation power supply unit 34 based on, for example, the state of the fuel cell unit 2. The startup power supply unit 34 supplies power to the water supply unit 31, the startup material supply unit 32, the heating energy supply unit 33, and the startup control unit 35. The activation power supply unit 34 is, for example, a small generator or a battery, and the activation control unit 35 is a computer. The small power generator is driven using, for example, gasoline, light oil, kerosene, alcohol, LP gas, or the like as fuel.

  The water supply unit 31 stores water and supplies the water to the reformer 22 of the fuel cell unit 2 when the fuel cell unit 2 is activated. The water supply unit 31 includes, for example, a water storage unit 311, a pump 312, and a startup water pipe 313. The water storage unit 311 is a tank that stores water (for example, pure water). The water storage unit 311 is detachably connected to the water vapor generation unit 46 of the fuel cell unit 2 via the startup water pipe 313. The pump 312 is provided on the activation water pipe 313 and supplies the water stored in the water storage unit 311 to the water vapor generation unit 46.

  The starting material supply unit 32 supplies the starting material to the reformer 22 during the starting operation of the fuel cell unit 2. The starting material supply unit 32 includes, for example, a starting material supply source 321 and a starting material pipe 322. The starting material supply source 321 is, for example, a gas cylinder that stores the starting material. The starting material supply source 321 is detachably connected to the raw fuel supply pipe 261 of the fuel cell unit 2 via the starting material pipe 322. In other words, the starting material supply source 321 is detachably connected to the reformer 22 via the starting material pipe 322 and the raw fuel supply pipe 261. As the starting material, for example, nitrogen, hydrogen, LP gas similar to raw fuel, city gas, bioethanol and the like are used.

  The heating energy supply unit 33 supplies energy used for heating the inside of the housing 21 of the fuel cell unit 2 during the start-up operation of the fuel cell unit 2. The heating energy supply unit 33 is connected to the temperature raising unit 24 in the housing 21. In the example shown in FIG. 2, the temperature raising unit 24 is a burner that burns fuel to heat the inside of the housing 21. The heating energy supply unit 33 includes, for example, a heating fuel supply source 331, a heating fuel pipe 332, and a heating blower 333. The heating fuel supply source 331 is, for example, a gas cylinder that stores heating fuel. The heating blower 333 delivers air. The heating fuel supply source 331 and the heating blower 333 are detachably connected to the temperature raising unit 24 via the heating fuel pipe 332. As the heating fuel, for example, LP gas, city gas, light oil or the like is used.

  In the start-up operation of the first fuel cell unit 2 among the plurality of fuel cell units 2, first, the heating fuel from the heating fuel supply source 331 and the air from the heating blower 333 are used for the above heating. The energy used is supplied to the temperature raising unit 24. And the inside of the housing 21 is heated when the heating fuel burns in the temperature raising section 24. Thereby, the reformer 22 and the fuel cell 23 are heated.

  Subsequently, the starting material from the starting material supply source 321 passes through the impurity removal unit 41 and is supplied to the reformer 22. Further, water from the water supply unit 31 is supplied to the steam generation unit 46, converted into water vapor by the steam generation unit 46, and then supplied to the reformer 22. Then, the starting material is steam reformed by the reformer 22 to generate fuel gas, which is supplied to the negative electrode of the fuel cell 23. Air containing an oxidant gas is supplied to the positive electrode of the fuel cell 23 by the blower 43 described above. Thereby, power generation by the fuel cell 23 is performed, and the reformer 22 is further heated by heat generated during power generation. Further, the water generated in the condensing unit 45 from the negative electrode exhaust gas from the fuel cell 23 is supplied to the water vapor generating unit 46.

  In the fuel cell system 1, until the reformer 22 and the fuel cell 23 reach a predetermined temperature and the output from the fuel cell 23 reaches a predetermined power generation amount and stabilizes, that is, the fuel cell unit 2 is in a steady operation state. Until it becomes, the above-mentioned starting operation is continued. When the steady operation of the fuel cell unit 2 is started and the water self-sustaining and the heat self-sustaining are established, the starting unit 3 is stopped. Specifically, in the starting unit 3, the supply of water from the water supply unit 31, the supply of the starting material from the starting material supply unit 32, and the energy from the heating energy supply unit 33 (that is, for heating) The supply of fuel and air) is stopped. In parallel with this, in the fuel cell unit 2, the supply of raw fuel from the raw fuel supply source 48 to the reformer 22 is started.

  And the connection part 310 of the water supply part 31 and the fuel cell unit 2, the connection part 320 of the starting material supply part 32 and the fuel cell unit 2, and the connection of the heating energy supply part 33 and the fuel cell unit 2 The connection in the unit 330 is released, and the starting unit 3 is removed from the fuel cell unit 2. Valves and check valves are provided on both sides of the connecting portions 310, 320, and 330 (that is, the starting unit 3 side and the fuel cell unit 2 side), and even after the starting unit 3 is removed, the steady state of the fuel cell unit 2 is provided. Driving will continue without hindrance.

  As described above, the start-up unit 3 can be detached from the fuel cell unit 2 after the start-up operation of the fuel cell unit 2 is completed (that is, after the start of steady operation). For this reason, it is possible to reduce the number of owned devices in the fuel cell unit 2 during steady operation, and it is possible to reduce the device failure probability during steady operation and reduce the load of device control. Moreover, the fall of the power transmission end power of the fuel cell unit 2 by the standby electric power etc. of the possessed apparatus which is not used at the time of steady operation can also be suppressed. As a result, the reliability of the fuel cell system 1 can be improved.

  In the fuel cell system 1, by providing the start-up power supply unit 34 in the start-up unit 3, it is possible to reduce power demand during start-up operation in the fuel cell unit 2. As a result, the capacity of the power receiving unit 40 of the fuel cell unit 2 can be reduced.

  In the fuel cell system 1 shown in FIG. 1, when the startup operation of the first fuel cell unit 2 is completed, the startup vehicle 6 moves and the second fuel cell unit 2 of the plurality of fuel cell units 2 moves. The activation unit 3 is arranged in the vicinity. As described above, since the activation unit 3 is loaded on the loading portion of the moving vehicle 61, the movement of the activation unit 3 between the plurality of fuel cell units 2 can be facilitated. Thereby, the some fuel cell unit 2 can be started easily. As the vehicle 61 of the starting vehicle 6, for example, a light truck is used, and the starting unit 3 is loaded on a loading platform that is a loading unit of the light truck.

  Considering the in-vehicle start unit 3, the weight of the start unit 3 is preferably 350 kg or less, and the length, width and height of the start unit housing 36 of the start unit 3 are 1900 mm or less, 1400 mm or less, 1500 mm or less, respectively. It is preferable that Further, in order to reduce the vibration of each structure during movement, the water supply unit 31, the activation material supply unit 32, the heating energy supply unit 33, the activation power supply unit 34, and the activation control unit 35 (see FIG. 2) The starter unit housing 36 is preferably securable. The water supply unit 31, the activation material supply unit 32, the heating energy supply unit 33, the activation power source unit 34, and the activation control unit 35 are preferably installed on a vibration isolation table.

  In the start-up operation of the second fuel cell unit 2, first, the water supply unit 31, the start-up material supply unit 32 and the heating energy supply unit 33 of the start-up unit 3, and the second fuel cell unit 2 Are connected at connection portions 310, 320, and 330, respectively, as in the case shown in FIG.

  FIG. 3 is a perspective view showing an example of a connection part 310 between the water supply part 31 and the fuel cell unit 2. The connection part 310 includes a connection end part 310a on the water supply part 31 side and a connection end part 310b on the fuel cell unit 2 side. In FIG. 3, in order to facilitate understanding of the drawing, piping extending from the connection end portions 310a and 310b is drawn with a broken line. The connection end portions 310a and 310b are substantially cylindrical, and a flow path through which water flows is provided in the central portion. A substantially quadrangular prism-shaped convex portion 310c extending in the radial direction is provided on the end surface of the connection end portion 310a. Further, a concave portion 310d having substantially the same shape as the convex portion 310c is provided on the end surface of the connection end portion 310b. When the water supply unit 31 and the fuel cell unit 2 are connected, the connection end portions 310a and 310b are fixed to each other while the convex portion 310c is fitted into the concave portion 310d.

  In the fuel cell system 1, the water supply unit 31, the starting material supply unit 32, and the heating energy supply unit 33 and the connection units 310, 320, and 330 of the fuel cell unit 2 have different shapes. Have. For example, similarly to the connection part 310 shown in FIG. 3, the connection parts 320 and 330 are also provided with projections and depressions on the end surface of the connection end part, and the shape, number or arrangement of the projections and depressions are connected. The portions 310, 320, and 330 are different from each other. Thereby, when connecting the starting unit 3 and the fuel cell unit 2, the water supply unit 31, the starting material supply unit 32, the heating energy supply unit 33, and the fuel cell unit 2 are connected without error. be able to.

  When the connection between the start unit 3 and the second fuel cell unit 2 is completed, the heating fuel from the heating fuel supply source 331 shown in FIG. The air from the heating blower 333 is supplied to the temperature raising unit 24, and the heating fuel is combusted, whereby the inside of the housing 21 is heated. Thereby, the reformer 22 and the fuel cell 23 are heated.

  Subsequently, the starting material from the starting material supply source 321 and the water vapor from the water supply unit 31 via the water vapor generating unit 46 are supplied to the reformer 22, and the starting material is steam reformed. Fuel gas is generated and supplied to the negative electrode of the fuel cell 23. Air containing an oxidant gas is supplied to the positive electrode of the fuel cell 23 by the blower 43. Thereby, power generation by the fuel cell 23 is performed, and the reformer 22 is further heated by heat generated during power generation. Further, the water generated in the condensing unit 45 from the negative electrode exhaust gas from the fuel cell 23 is supplied to the water vapor generating unit 46.

  Then, until the reformer 22 and the fuel cell 23 reach a predetermined temperature and the output from the fuel cell 23 reaches a predetermined power generation amount and stabilizes, that is, the second fuel cell unit 2 is in a steady operation state. Until it becomes, the above-mentioned starting operation is continued. When the steady operation of the second fuel cell unit 2 is started and the water self-sustaining and the heat self-sustaining are established, the starting unit 3 is stopped and removed from the fuel cell unit 2.

  During the start-up operation of the second fuel cell unit 2, the start-up unit 3 and the second fuel from the first fuel cell unit 2 (that is, the already-started fuel cell unit 2 that has completed the start-up operation). Electric power is supplied to at least one of the battery units 2.

  Specifically, for example, the output terminal from the fuel cell 23 of the first fuel cell unit 2 is configured such that the water supply unit 31, the starting material supply unit 32, the heating energy supply unit 33, and the like of the starting unit 3. A part or all of the power output from the fuel cell 23 is supplied to the configuration of the activation unit 3. Further, for example, the output terminal of the first fuel cell unit 2 from the fuel cell 23 is connected to the power receiving unit 40 of the second fuel cell unit 2, and a part of the power output from the fuel cell 23. Alternatively, the whole is supplied to the configuration of the fuel cell unit 2 such as the reformer 22 and the blower 43 via the power receiving unit 40. Alternatively, in the first fuel cell unit 2, power generation by the turbine is performed using the combustion heat generated in the exhaust gas combustion unit 47, and the power generated by the power generation is used as the starting unit 3 or the second fuel cell unit. 2 may be supplied. The electric power from the first fuel cell unit 2 may be supplied to both the starting unit 3 and the second fuel cell unit 2.

  Further, during the start-up operation of the second fuel cell unit 2, the heat generated in the first fuel cell unit 2 (that is, the activated fuel cell unit 2) is converted into the second fuel cell unit 2. It is used as a heating source.

  Specifically, for example, the combustion heat generated in the exhaust gas combustion unit 47 of the first fuel cell unit 2 is heated by the water vapor generation unit 46 in the second fuel cell unit 2 and a reformer. It is used as a heat source for preheating the starting material supplied to 22 and preheating the air supplied to the fuel cell 23. Further, for example, the negative electrode exhaust gas or the positive electrode exhaust gas of the first fuel cell unit 2 is heated through the heat exchanger to heat the water in the steam generation unit 46 and to preheat the starting material supplied to the reformer 22. It is used as a heating source for preheating the air supplied to the fuel cell 23. Alternatively, the air is heated by the combustion heat or the exhaust gas of the first fuel cell unit 2, and the heated air is supplied into the housing 21 of the second fuel cell unit 2. The internal reformer 22 and the fuel cell 23 may be heated.

  The above-described power supply by the activated fuel cell unit 2 is the same during the startup operation of the third and subsequent fuel cell units 2. That is, in the fuel cell system 1, the start-up unit 3 and the second and subsequent fuel cells are started from the already-started fuel cell unit 2 in which the start-up operation is completed at the start-up operation of the second and subsequent fuel cell units 2. Electric power is supplied to at least one of the units 2. Thereby, at the time of start-up operation of the second and subsequent fuel cell units 2 in the fuel cell system 1, at least one of the power generated by the start-up unit 3 and the power supplied from the outside of the fuel cell system 1 is reduced. be able to. In the start-up operation of the third and subsequent fuel cell units 2, even if there is only one start-up fuel cell unit 2 that supplies power to the fuel cell unit 2 in which the start-up operation is performed, There may be.

  When electric power is supplied from the activated fuel cell unit 2 to the activation unit 3, it is possible to reduce the power that needs to be generated by the activation power supply unit 34 in the activation unit 3. When the power supplied from the activated fuel cell unit 2 to the activation unit 3 is relatively large, for example, the power required by the activation unit 3 is activated without driving the activation power source 34. The power from the fuel cell unit 2 can be covered. When electric power is supplied from the activated fuel cell unit 2 to the second and subsequent fuel cell units 2, the electric power supplied from the outside of the fuel cell system 1 to the second and subsequent fuel cell units 2 is reduced. be able to.

  The above-described use of the activated fuel cell unit 2 as a heating source is the same during the startup operation of the third and subsequent fuel cell units 2. That is, in the fuel cell system 1, during the startup operation of the second and subsequent fuel cell units 2, the heat generated in the activated fuel cell unit 2 that has completed the startup operation is the fuel for the second and subsequent units. Used as a heating source for the battery unit 2. Thereby, at the time of starting operation of the second and subsequent fuel cell units 2 in the fuel cell system 1, the second and subsequent fuel cell units 2 can be quickly heated, and the time required for the starting operation can be shortened. Can do. Alternatively, the energy supplied from the starting unit 3 to the second and subsequent fuel cell units 2 can be reduced. In the start-up operation of the third and subsequent fuel cell units 2, even if there is only one start-up fuel cell unit 2 used as a heating source of the fuel cell unit 2 in which the start-up operation is performed, It may be a stand.

  In the fuel cell system 1, during the steady operation of each fuel cell unit 2, water self-sustained operation is not performed, and it is necessary to continuously supply water stored in the water supply source to the reformer 22 as water vapor. In this case, steam may be supplied from the water supply source to the reformer 22 even during the start-up operation. In this case, the water supply unit 31 may be omitted from the activation unit 3. Further, when the starting material contains water necessary for reforming in the reformer 22 such as undistilled bioethanol, the water supply unit 31 may be omitted from the starting unit 3.

  The starting material supplied to the reformer 22 from the starting material supply unit 32 may be, for example, a gas different from the raw fuel. When the starting material is nitrogen gas that does not become a raw fuel or hydrogen gas that is a fuel gas, the steam reforming in the reformer 22 is not required during the starting operation of the fuel cell unit 2, so that the water supply unit 31 may be omitted from the activation unit 3.

  In the fuel cell system 1, when the starting material supplied from the starting material supply unit 32 to the reformer 22 is the same as the raw fuel supplied from the raw fuel supply source 48 described above, During the starting operation, the raw fuel from the raw fuel supply source 48 may be supplied to the reformer 22 as a starting material. In this case, the activation material supply unit 32 may be omitted from the activation unit 3.

  In the fuel cell system 1, when the heating fuel supplied from the heating energy supply unit 33 to the temperature raising unit 24 is the same as the raw fuel supplied from the raw fuel supply source 48, the start-up operation of the fuel cell unit 2 is performed. At this time, the raw fuel from the raw fuel supply source 48 may be supplied to the temperature raising unit 24 as a heating fuel. In addition, air may be supplied to the temperature raising unit 24 using the blower 43 of the fuel cell unit 2. As described above, when the heating fuel and air are supplied from the raw fuel supply source 48 and the blower 43 to the temperature raising unit 24, the heating energy supply unit 33 may be omitted from the activation unit 3.

  In addition, when the fuel cell unit 2 is in a steady operation, the heat self-sustaining operation is not performed, and when the heating in the housing 21 by the temperature raising unit 24 is necessary, the fuel cell unit 2 has a fuel supply source for heating. The heating fuel and air may be supplied from the heating fuel supply source and the blower 43 of the fuel cell unit 2 to the temperature raising unit 24. Also in this case, the heating energy supply unit 33 may be omitted from the activation unit 3.

  As described above, the activation unit 3 may include at least two supply units among the water supply unit 31, the activation material supply unit 32, and the heating energy supply unit 33. Even in this case, the activation unit 3 can be removed from the fuel cell unit 2 after the steady operation of each fuel cell unit 2 is started, as described above. For this reason, it is possible to realize a reduction in the equipment failure probability during steady operation of each fuel cell unit 2 and a reduction in equipment control load. In addition, it is possible to suppress a decrease in power transmission end power of each fuel cell unit 2 due to standby power of the owned equipment that is not used during steady operation. Furthermore, after the start-up operation of the plurality of fuel cell units 2 is completed, the start-up unit 3 can be maintained in parallel with the steady operation of the plurality of fuel cell units 2.

  Further, each of the connection parts between the at least two supply parts and each fuel cell unit 2 has a different shape, so that each of the at least two supply parts and each fuel cell unit 2 is similar to the above. Can be connected without error.

  However, the activation unit 3 preferably includes all of the water supply unit 31, the activation material supply unit 32, and the heating energy supply unit 33. Thereby, the starting operation of the fuel cell unit 2 having various structures can be easily performed. Therefore, even when the fuel cell system 1 includes a plurality of fuel cell units 2 having different structures, the start-up operation of the plurality of fuel cell units 2 can be easily performed by a single start-up unit 3. it can.

  FIG. 4 is a diagram showing a configuration of a fuel cell system 1a according to the second embodiment of the present invention. The fuel cell system 1 a includes a plurality of fuel cell units 2 and a plurality of activation units 3. In the example shown in FIG. 4, the number of activation units 3 is the same as the number of fuel cell units 2. The configuration of each fuel cell unit 2 and the configuration of each activation unit 3 are the same as those shown in FIG.

  Each of the plurality of fuel cell units 2 is a power generation unit that generates power using a fuel cell. The plurality of start-up units 3 are detachably connected to the plurality of fuel cell units 2 and are used for start-up operations of the connected fuel cell units 2, respectively. In the fuel cell system 1a, the startup operations of the plurality of fuel cell units 2 are performed in parallel by the plurality of startup units 3.

  In the fuel cell system 1a, as in the fuel cell system 1 shown in FIG. 1, each start unit 3 is removed from the fuel cell unit 2 after the start operation of the fuel cell unit 2 is completed (that is, after the start of steady operation). be able to. For this reason, it is possible to reduce the number of owned devices in each fuel cell unit 2 during steady operation, and it is possible to reduce the device failure probability during steady operation and reduce the load of device control. In addition, it is possible to suppress a decrease in power transmission end power of each fuel cell unit 2 due to standby power of the owned equipment that is not used during steady operation. Furthermore, maintenance of each starting unit 3 can be performed in parallel with the steady operation of the plurality of fuel cell units 2. As a result, the reliability of the fuel cell system 1a can be improved.

  In the fuel cell system 1a, as described above, since the startup operations of the plurality of fuel cell units 2 are performed in parallel, the time required to complete the startup operations of all the fuel cell units 2 can be shortened. Even if some of the startup units 3 fail, the startup operation of the plurality of fuel cell units 2 can be performed by using another startup unit 3 instead of the startup unit 3. . Thereby, the reliability of the fuel cell system 1a can be further improved. The number of activation units 3 provided in the fuel cell system 1a is not necessarily the same as the number of fuel cell units 2, and may be larger or smaller than the number of fuel cell units 2.

  Various modifications are possible in the fuel cell systems 1 and 1a described above.

  For example, in the fuel cell systems 1 and 1a, the water supply unit 31, the activation material supply unit 32, the heating energy supply unit 33, and the connection units 310, 320, and 330 of the heating unit 2 and the fuel cell unit 2, respectively, It is sufficient if they have different shapes from each other, and the shapes may be various shapes other than the above-described concavity and convexity fitting.

  The temperature raising unit 24 is not necessarily a burner, and may be, for example, a hot air injecting unit that injects hot air into the housing 21. In this case, for example, the heating energy supply unit 33 supplies air to the heating fuel supply source 331 that stores the heating fuel, the heating fuel combustion unit that burns the heating fuel, and the heating fuel combustion unit. And a blower 333 for heating. For example, when an oil burner using light oil as a fuel is used as the heating fuel combustion unit, a diesel generator driven by the light oil may be used as the startup power supply unit 34. Alternatively, a diesel generator may be used as the heating fuel combustion unit and the startup power supply unit 34, and the waste heat of the diesel generator may be used as heating energy supplied to the temperature raising unit 24. Further, a gas turbine generator using LP gas as fuel is used as a heating fuel combustion unit and a starting power supply unit 34, and the high temperature exhaust gas of the gas turbine generator is used as heating energy supplied to the temperature raising unit 24. It may be used.

  When the heating fuel in the temperature raising unit 24 is the same as the raw fuel (for example, LP gas or city gas) supplied from the raw fuel supply source 48, the heating fuel supply from the heating energy supply unit 33 is performed. The source 331 may be omitted, and the raw fuel from the raw fuel supply source 48 may be supplied to the heating fuel combustion unit as the heating fuel. When air is supplied to the heating fuel combustion unit using the blower 43 of the fuel cell unit 2, the heating blower 333 may be omitted from the heating energy supply unit 33.

  The temperature raising unit 24 may be an electric heater. In this case, the heating energy supply unit 33 includes, for example, a power supply unit that supplies power to the temperature raising unit 24. For example, a small generator or a battery is used as the power supply unit. The small power generator is driven using, for example, gasoline, light oil, kerosene, alcohol, LP gas, or the like as fuel. Or the above-mentioned starting power supply part 34 may be utilized as the said electric power supply part.

  In the fuel cell systems 1 and 1a described above, the water vapor contained in the negative electrode exhaust gas from the fuel cell 23 is taken out as water in the condensing unit 45 and then supplied to the water vapor generating unit 46. A part of the gas may be supplied to the reformer 22 in a gaseous state. Even in this case, it is possible to realize the water self-sustained operation in the fuel cell unit 2 in the steady operation.

  In the fuel cell unit 2, a plurality of fuel cells 23 may be disposed in the housing 21.

  In the fuel cell systems 1 and 1a, the activation unit 3 is used for the activation operation of the fuel cell unit 2, and the activation operation of the fuel cell unit 2 is not necessarily performed by the activation unit 3 alone. For example, the starting operation of the fuel cell unit 2 may be performed by using the starting unit 3 together with another configuration.

  In the fuel cell system 1 shown in FIG. 1, for example, when the starter unit 3 can be easily connected to each fuel cell unit 2 without moving, the moving vehicle 61 is omitted, and the starter unit 3 has a predetermined position. May be arranged.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1,1a Fuel cell system 2 Fuel cell unit 3 Starting unit 21 Housing 22 Reformer 23 Fuel cell 31 Water supply part 32 Starting material supply part 33 Heating energy supply part 61 Vehicle

Claims (5)

A fuel cell system,
A reformer that reforms raw fuel to generate fuel gas, a solid oxide fuel cell that generates power using the fuel gas and oxidant gas, and the reformer and the fuel cell are housed. A plurality of fuel cell units each comprising a housing;
An activation unit that is sequentially connected to the plurality of fuel cell units in a detachable manner and is used for the activation operation of the connected fuel cell units;
With
When starting the second and subsequent fuel cell units among the plurality of fuel cell units, the startup unit and the second and subsequent fuel cell units are changed from the already started fuel cell units. A fuel cell system, wherein power is supplied to at least one of the fuel cell systems. The fuel cell system according to claim 1,
A fuel cell characterized in that heat generated in the activated fuel cell units is used as a heat source for the second and subsequent fuel cell units during the startup operation of the second and subsequent fuel cell units. system. The fuel cell system according to claim 1 or 2,
A fuel cell system, further comprising a moving vehicle on which the activation unit is loaded. The fuel cell system according to any one of claims 1 to 3,
The reformer performs steam reforming on the raw fuel,
The activation unit is
A water supply section for storing water and supplying the water to the reformer;
An energy supply unit for heating for supplying energy used for heating the interior of the housing;
A starting material supply unit for supplying a starting material to the reformer;
A fuel cell system comprising at least two supply units. A fuel cell system,
A reformer that reforms raw fuel to generate fuel gas, a solid oxide fuel cell that generates power using the fuel gas and oxidant gas, and the reformer and the fuel cell are housed. A plurality of fuel cell units each comprising a housing;
A plurality of starter units each detachably connected to the plurality of fuel cell units, each used for start-up operation of the connected fuel cell units;
A fuel cell system comprising:

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