WO2021140852A1

WO2021140852A1 - Fuel cell power generating system

Info

Publication number: WO2021140852A1
Application number: PCT/JP2020/046872
Authority: WO
Inventors: 竹内　良昭; 正和久原
Original assignee: 三菱重工業株式会社
Priority date: 2020-01-09
Filing date: 2020-12-16
Publication date: 2021-07-15
Also published as: JP2021111508A; JP7446113B2

Abstract

This fuel cell power generating system has a plurality of fuel cell cartridges, the fuel cell power generating system comprising: a plurality of fuel cell units configured by two or more cell groups each formed as a minimum unit of electrical output by a plurality of cell stacks built into the fuel cell cartridge; and a plurality of power conversion devices that are provided for each of the plurality of fuel cell units, the power conversion devices performing power conversion of the output power of the fuel cell units, two or more cell groups being serially connected in the fuel cell unit.

Description

Fuel cell power generation system

This disclosure relates to a fuel cell power generation system that generates power using a fuel cell.

A fuel cell that generates electricity by chemically reacting a fuel gas with an oxidizing gas has characteristics such as excellent power generation efficiency and environmental friendliness. Of these, solid oxide fuel cells (Solid Oxide Fuel Cell: SOFC) use ceramics such as zirconia ceramics as the electrolyte, and gasify hydrogen, city gas, natural gas, petroleum, methanol, and carbon-containing raw materials. Gas such as gasification gas produced in the above is supplied as fuel gas and reacted in a high temperature atmosphere of about 700 ° C. to 1000 ° C. to generate power.

A fuel cell power generation system that generates electricity from such a fuel cell is composed of a fuel cell module in which a plurality of fuel cell cartridges in which a plurality of cell stacks are assembled by a fuel supply header or the like are modularized, and a fuel cell module. A power conversion device (inverter, etc.) such as a power conditioner (PCS) for converting the output DC power into a predetermined AC power and supplying it to a power supply destination (for example, a load facility or a power system). (See Patent Documents 1 to 3). For example, in the electric power system of Patent Document 1, a PCS is provided for each fuel cell module, and a plurality of these PCSs are connected in parallel to the bus and connected to the electric power system via a switching unit. ing.

Japanese Unexamined Patent Publication No. 2018-50428 Japanese Unexamined Patent Publication No. 2005-222863 Japanese Unexamined Patent Publication No. 2014-71998

For example, as shown in Patent Document 1, a fuel cell power generation system is configured to obtain a predetermined output by using one or more fuel cell modules, and as a specific configuration of the fuel cell module, for example, as shown in FIG. The system configuration is conceivable. In FIG. 6, a plurality of fuel cell cartridges constituting the fuel cell power generation system are grouped into one or more groups (four groups in FIG. 6), and the fuel cell cartridges are connected in series within each group. At this time, after grouping the plurality of cell stacks of each fuel cell cartridge into a plurality of groups (hereinafter referred to as cell groups) which are the minimum units of electric output, each cell group is a cell group of another fuel cell cartridge. It is connected in series so that it is connected to either one. Then, it is connected to one inverter via a chopper (DC / DC converter) provided for each group of fuel cell cartridges described above, and is output to a power supply destination such as a power system via this inverter. Therefore, the PCS is composed of a plurality of choppers and inverters.

However, in the fuel cell power generation system as shown in FIG. 6, one PCS (inverter) is provided for all the fuel cell cartridges constituting the fuel cell module, and the electric system is one system. Therefore, if a trouble such as a failure occurs in the PCS or one of the plurality of fuel cell cartridges connected in series, the electric output from the fuel cell module may not be possible. Further, since a plurality of cell groups are connected in parallel in each fuel cell cartridge, the output current of the fuel cell cartridge is large, the wiring connecting the fuel cell cartridges is thickened by that amount, and the power transmission loss is also large. Further, the PCS needs to be selected or custom-made according to the output of the fuel cell module, which tends to increase the cost.

In view of the above circumstances, at least one embodiment of the present invention aims to provide a fuel cell power generation system that is highly reliable and can be constructed at low cost.

The fuel cell power generation system according to at least one embodiment of the present invention is
A fuel cell power generation system having multiple fuel cell cartridges.
A plurality of fuel cell units composed of two or more cell groups each formed as a minimum unit of electric output by a plurality of cell stacks built in the fuel cell cartridge, and a plurality of fuel cell units.
A plurality of power conversion devices for converting the output power of the fuel cell unit, which are provided for each of the plurality of fuel cell units, are provided.
In the fuel cell unit, the two or more cell groups are connected in series.

According to at least one embodiment of the present invention, a fuel cell power generation system that is highly reliable and can be constructed at low cost is provided.

It is a figure which shows schematic the structure of the fuel cell power generation system which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of the fuel cell cartridge which concerns on one Embodiment of this invention. It is a figure which shows typically the fuel cell unit which consists of the cell group which has two fuel cell cartridges which concerns on one Embodiment of this invention. It is a figure which shows the temperature of each fuel cell cartridge controlled by the control device which concerns on one Embodiment of this invention. It is a figure which shows the output of each fuel cell cartridge in the case of FIG. 4A. It is a figure which shows the temperature of each fuel cell cartridge when the current is controlled as shown in FIG. 5B, and is the reference figure with respect to FIG. 4A. It is a reference figure with respect to FIG. 4B which is the reference figure which shows the output of each fuel cell cartridge corresponding to FIG. 5A. It is a reference figure which shows roughly the structure of the fuel cell power generation system. It shows one aspect of the cell stack which concerns on one Embodiment of this invention. It shows one aspect of the SOFC module which concerns on one Embodiment of this invention. The cross section of the SOFC cartridge according to the embodiment of the present invention is shown, and the upper portion shown corresponds to FIG.

Hereinafter, an embodiment of the fuel cell power generation system 1 according to the present invention will be described with reference to the drawings. FIG. 1 is a diagram schematically showing a configuration of a fuel cell power generation system 1 according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing the configuration of the fuel cell cartridge 203 according to the embodiment of the present invention. Further, FIG. 3 is a diagram schematically showing a fuel cell unit 3 composed of a cell group G included in the two fuel cell cartridges 203 according to the embodiment of the present invention.

As shown in FIG. 1, this fuel cell power generation system 1 is a power generation system having a plurality of fuel cell cartridges 203. These plurality of fuel cell cartridges 203 may be modularized, and the fuel cell power generation system 1 may include one or more fuel cell modules 201. In the fuel cell cartridge 203, a plurality of cell stacks 101 are assembled by, for example, a fuel supply header such as a casing 229 (229a, 229b) described later (see FIGS. 2 and 9). Further, the fuel cell module 201 is the maximum unit of the fuel cell including the fuel cell cartridge 203 and the pressure vessel 205.

Then, as shown in FIG. 1, the fuel cell power generation system 1 includes a plurality of fuel cell units 3 each composed of cell groups G included in one or more fuel cell cartridges 203, and each of the plurality of fuel cell units 3. A plurality of power conversion devices 4 (PCS, etc.) provided for the above are provided. Each of these configurations will be described.
A detailed description of the fuel cell module 201 and the fuel cell cartridge 203 will be described at the end.

The fuel cell unit 3 is composed of two or more cell groups G formed by a part of a plurality of cell stacks 101 built in the fuel cell cartridge 203. More specifically, as shown in FIG. 2, the plurality of cell stacks 101 included in each fuel cell cartridge 203 are grouped into a plurality of cell groups G, and then connected to the current collector plate 241 for each cell group G. To. A current collector rod 242 is connected to each current collector plate 241 so that the DC power generated from each current collector rod 242 can be taken out to the outside. That is, the cell group G is the minimum unit of the electric output from the fuel cell cartridge 203.

For example, as shown in FIGS. 1 and 3, each fuel cell unit 3 is composed of a cell group G included in one or more fuel cell cartridges 203. That is, as shown in FIG. 1, each fuel cell unit 3 may be composed of a plurality of cell groups G included in one fuel cell cartridge 203. Alternatively, as shown in FIG. 3, each fuel cell unit 3 may be composed of a cell group G included in each of the plurality of fuel cell cartridges 203. Further, in FIGS. 1 and 3, all cell groups G included in one fuel cell cartridge 203 belong to any fuel cell unit 3, but in some other embodiments, one fuel cell. Each of the plurality of cell groups G included in the cartridge 203 may belong to any of the plurality of fuel cell units 3 different from each other. In other words, the plurality of fuel cell units 3 may be configured to include different cell groups G of the same fuel cell cartridge 203.

This makes it possible to set the number of cell groups G included in the fuel cell unit 3 to a desired number. As will be described later, a plurality of cell groups G are connected in series in the fuel cell unit 3. Therefore, by setting the number of cell groups G included in the fuel cell unit 3 according to the operating point of the connected power conversion device 4, the voltage of the fuel cell unit 3 is increased according to the operating point. Is possible. Therefore, it is possible to adopt a general-purpose low-priced power conversion device 4, and it is possible to construct the fuel cell power generation system 1 at a lower cost than in the case of FIG.

In the embodiment shown in FIGS. 1 and 3, the fuel cell module 201 includes 20 fuel cell cartridges 203. Further, each fuel cell cartridge 203 includes four cell groups G. Then, in the embodiment shown in FIG. 1, in each fuel cell unit 3, one fuel cell unit 3 is assembled in all (four in total) cell groups G included in one fuel cell cartridge 203. That is, the fuel cell unit 3 is assembled for each fuel cell cartridge 203. On the other hand, in the embodiment shown in FIG. 3, each fuel cell unit 3 is assembled by all the cell groups G each of the two fuel cell cartridges 203, and is assembled by a total of eight cell groups G. That is, the fuel cell unit 3 is assembled for each of the two fuel cell cartridges 203.

The power conversion device 4 is a device provided for each of the plurality of fuel cell units 3 described above to perform power conversion of the output power of the fuel cell unit 3. More specifically, each power converter 4 includes a DC / DC converter (not shown) such as a chopper connected to each fuel cell unit 3 and an inverter (not shown) connected to the DC / DC converter. For example, a power conditioner (PCS: Power Conditioning Subsystem) or the like.

In the embodiment shown in FIG. 1, since the fuel cell unit 3 is composed of one fuel cell cartridge 203, the fuel cell module 201 includes a total of 20 fuel cell units 3 which is the same number as the fuel cell cartridge 203. ing. Therefore, the total number of power conversion devices 4 is 20. On the other hand, in the embodiment shown in FIG. 3, since the fuel cell unit 3 is composed of two fuel cell cartridges 203, the fuel cell module 201 includes a total of 10 fuel cell units 3. Therefore, the total number of power conversion devices 4 is 10.

The number of DC / DC converters included in one power converter 4 is arbitrary, and may be determined in consideration of cost, controllable power range, withstand voltage, and the like. That is, in order to reduce the cost, it is better that the number of DC / DC converters is small, but there is a limit to the magnitude of the DC current that can be input to one DC / DC converter, and it is determined by the balance. Further, the number of power conversion devices 4 provided for one fuel cell unit 3 is arbitrary, and a plurality of power conversion devices 4 may be connected in parallel to one fuel cell unit 3.

As described above, each fuel cell unit 3 is composed of two or more cell groups G. As shown in FIGS. 1 and 3, in each fuel cell unit 3, two or more cells possessed by each fuel cell unit 3 Group G is connected in series.
Specifically, in the embodiment shown in FIG. 1, adjacent cell groups G are connected in series so that a plurality of (four) cell groups G arranged in parallel with each other in one fuel cell cartridge 203 are connected in series. It is connected by wiring (first wiring 41). Further, cell groups G located at both ends of each fuel cell cartridge 203 are connected to the power conversion device 4 by wiring (third wiring 43). As a result, a total of four cell groups G serially connected to each fuel cell unit 3 and a connection between the fuel cell unit 3 and the power conversion device 4 are formed.

On the other hand, in the embodiment shown in FIG. 3, a plurality (four) arranged in parallel with each other in each fuel cell cartridge 203 so that a total of eight cell groups G included in the two fuel cell cartridges 203 are connected in series. The cell groups G adjacent to each other are connected in series by the first wiring 41, and the cell groups G located at the same side ends between the two fuel cell cartridges 203 are connected to each other by wiring (second wiring 42). ing. Further, two cell groups G located at the ends of the two fuel cell cartridges 203 on the side opposite to the side where the second wiring 42 is located are connected to the power conversion device 4 by the third wiring 43, respectively. As a result, a total of eight cell groups G serially connected to each fuel cell unit 3 and a connection between the fuel cell unit 3 and the power conversion device 4 are formed.

In the embodiment shown in FIGS. 1 and 3, a plurality of cell groups G included in one fuel cell cartridge 203 are connected by the first wiring 41 in the order in which they are arranged, but a series connection is formed in the other order. You may have. Further, in the embodiment shown in FIG. 3, when one fuel cell unit 3 is configured by two fuel cell cartridges 203, the second wiring 42 is one, but two or more second wirings 42 A series connection may be formed by wiring such that is used.

In the fuel cell power generation system 1 having the above-described configuration, even if a trouble such as a failure occurs in any of the power conversion devices 4 or the fuel cell cartridge 203, the fuel cell cartridge 203 is electrically independent for each fuel cell unit 3. Therefore, the fuel cell unit 3 composed of the cell group G of the other fuel cell cartridge 203 is not affected, and the supply of the generated power can be continued. Specifically, even if any one of the fuel cell cartridges 203 fails, power can be output from the remaining 19 fuel cell cartridges 203 (fuel cell unit 3) in FIG. 1, and the remaining power can be output in FIG. Power can be output from the 18 fuel cell cartridges 203 (the remaining 9 fuel cell units 3), improving system redundancy. Further, by adjusting the number of cell groups G constituting each fuel cell unit 3 to adjust the output voltage, for example, a PCS (power conversion device 4) for a solar cell can be used.

According to the above configuration, the fuel cell power generation system 1 includes a plurality of fuel cell cartridges 203, and the plurality of cell stacks 101 incorporated in each fuel cell cartridge 203 are a plurality of units which are the minimum units of electric output. It is divided into cell groups G. The fuel cell unit 3 is composed of two or more of such cell groups G, and by providing a power conversion device 4 for each fuel cell unit 3, power conversion is performed for each fuel cell unit 3. It is configured as follows. Then, all the cell groups G belonging to each fuel cell unit 3 are connected in series.

As a result, even if a trouble such as a failure occurs in any of the plurality of power conversion devices 4 and the fuel cell cartridge 203, the fuel cell composed of the remaining power conversion device 4 and the remaining fuel cell cartridge 203 The power from the unit 3 can be output to a power supply destination 7 such as a power system, and the system can be made redundant, so that a highly reliable fuel cell power generation system 1 can be provided. For example, when one power conversion device 4 is provided for the fuel cell module 201 (when there is only one electric system), if the power conversion device 4 fails, the fuel cell power generation system 1 cannot output. According to the above configuration, the fuel cell power generation system 1 can continue to supply power. Further, the output current output from each fuel cell unit 3 can be reduced as compared with connecting the fuel cell cartridges 203 in series (see FIG. 6). Therefore, it is possible to reduce the current collection loss by such a low current, and it is also possible to reduce the power transmission loss by using a thinner wiring.

Further, by providing the power conversion device 4 for each fuel cell unit 3 as described above, it is possible to adopt a general-purpose low-priced power conversion device 4 for solar power generation, for example. Therefore, it is not necessary to prepare a power conversion device 4 capable of power conversion of all the fuel cell cartridges 203 included in the fuel cell power generation system 1 by special order, and the fuel cell power generation system 1 can be constructed at a lower cost. it can.

In some embodiments, as shown in FIGS. 1 and 3, the number of cell groups G constituting the fuel cell unit 3 described above may be an even number. When this number is an even number, it is possible to unify the power extraction unit (collecting rod 242) from the fuel cell unit 3 to either the upper part or the lower part of the fuel cell cartridge 203.

In the embodiment shown in FIGS. 1 and 3, in the fuel cell cartridge 203, the directions of the positive terminal (+) and the negative terminal (−) of the four cell groups G alternate at the upper or lower part of the fuel cell cartridge 203. They are arranged side by side. In the embodiment shown in FIG. 1, since the number of cell groups G included in the fuel cell cartridge 203 is an even number, the directions of the terminals of the cell groups G on both ends of the fuel cell cartridge 203 are opposite to each other. That is, when the positive terminal of the cell group G on one end side is on the upper part of the fuel cell cartridge 203, the negative terminal of the cell group G on the other end side is on the same upper part. Similarly, in the embodiment shown in FIG. 3, the fuel cell unit 3 has eight cell groups G by being composed of the same two fuel cell cartridges 203 as those in FIG. 1, and is a power conversion device. The directions of the terminals of the two cell groups G connected to 4 are reversed. Therefore, both of the two third wirings 43 connecting the power conversion device 4 and the fuel cell unit 3 are unified at the upper part.

According to the above configuration, the power extraction unit from the fuel cell cartridge 203 can be unified to either the upper part or the lower part of the fuel cell cartridge 203, and the construction can be facilitated.

Further, in some embodiments, as shown in FIG. 1, in the fuel cell power generation system 1, at least a part of the output power output by the plurality of power conversion devices 4 described above is, for example, a power system or a load facility. A power output circuit 5 for outputting to the power supply destination 7 is further provided. That is, the power output circuit 5 is provided between the plurality of power conversion devices 4 included in the fuel cell power generation system 1 and the power supply destination 7. The power output circuit 5 has a plurality of switches 51 capable of switching the connection state between the plurality of power conversion devices 4 and the power supply destination 7. That is, each power conversion device 4 is connected to the power supply destination 7 via the switch 51, and when the switch 51 is turned on, the power conversion device 4 is electrically connected to the power supply destination 7 and is turned off. Then the connection is released. This makes it possible to individually disconnect the plurality of fuel cell units 3 from the fuel cell power generation system 1.

In the embodiment shown in FIG. 1, the power supply destination 7 is a power system. Further, the power output circuit 5 includes an AC step-up transformer 52, and the plurality of switches 51 described above are each connected to the AC step-up transformer 52. Then, the AC step-up transformer 52 boosts the output voltage of the fuel cell module 201 so as to match the voltage of the power system, so that the fuel cell power generation system 1 becomes the power system.

According to the above configuration, the connection between each of the plurality of power conversion devices 4 and the power supply destination 7 can be individually disconnected by a switch included in the power output circuit. As a result, the fuel cell unit 3 in which the failure has occurred can be easily separated. Therefore, the remaining fuel cell unit 3 can be used to continue supplying electric power to the electric power supply destination, and maintenance work such as replacement and repair of the failed fuel cell unit 3 can be facilitated.

Next, an embodiment relating to control of the current value output from the fuel cell cartridge 203 will be described with reference to FIGS. 4A to 5B. FIG. 4A is a diagram showing the temperature of each fuel cell cartridge 203 controlled by the control device 6 according to the embodiment of the present invention. FIG. 4B is a diagram showing the output of each fuel cell cartridge 203 in the case of FIG. 4A. FIG. 5A is a diagram showing the temperature of each fuel cell cartridge 203 when the current is controlled as in FIG. 5B, and is a reference diagram with respect to FIG. 4A. Further, FIG. 5B is a reference diagram showing the output of each fuel cell cartridge 203 corresponding to FIG. 5A, and is a reference diagram with respect to FIG. 4B.

For example, the output of a single cell of a fuel cell such as an SOFC cell, which will be described later, increases as the temperature rises, but the temperature corresponds to the current value due to self-reaction heat generation. However, the upper limit temperature is determined from the durability of the cell, and the load (resistance value) of the power conversion device 4 to which the fuel cell cartridge 203 is connected is adjusted so that the upper limit temperature is not exceeded from the fuel cell cartridge 203. It is necessary to adjust the output current.

Here, the plurality of fuel cell cartridges 203 included in the fuel cell module 201 are housed in the pressure vessel 205 described later (see FIG. 7), and the fuel cell cartridges located at the ends of the pressure vessel 205 with respect to the central portion. The heat dissipation of the one is relatively large. Therefore, the temperature of the fuel cell cartridge 203 located at the end of the pressure vessel 205 is relatively lower than that at the center. Further, when there is a performance difference of the fuel cell cartridge 203 due to an assembly accuracy, a performance variation of the fuel cell 105, or the like, the temperature of the fuel cell cartridge 203 located at the center of the pressure vessel 205 also varies.

At this time, for example, when the power converter 4 (DC / DC converter) is controlled so that the current becomes constant, for example, the maximum value, as shown in FIG. 5B, the heat dissipation is relatively large as shown in FIG. 5A. The temperature of the fuel cell cartridge 203 on the end side of the pressure vessel 205 drops. Further, as shown in FIG. 5B, the temperature varies in the central portion of the pressure vessel 205. As a result, each fuel cell cartridge 203 having a temperature less than the upper limit temperature is generating electricity in a state where the maximum performance is not fully achieved.

Therefore, in some embodiments, as shown in FIG. 1, the fuel cell power generation system 1 includes a plurality of temperature measuring units 62 for detecting the temperature of each of the plurality of fuel cell cartridges 203, and a plurality of these temperature measuring units 62. Further, a control device 6 configured to control the output (output power) of each of the plurality of power conversion devices 4 so that each temperature of the fuel cell cartridge 203 becomes a specified temperature Tc (see FIG. 4A). You may prepare. Specifically, the control device 6 may control the output of each of the plurality of power conversion devices 4 by adjusting the load of each. With this control, the temperature of each fuel cell cartridge 203 can be brought close to the upper limit temperature to generate electricity, so that the maximum performance can be brought out.

The above-mentioned specified temperature Tc is, for example, a temperature equal to or less than the above-mentioned upper limit temperature. The closer the specified temperature Tc is to the upper limit temperature, the higher the output of the fuel cell cartridge 203. Therefore, the specified temperature Tc is set to a value smaller than the upper limit temperature by α temperature so as to avoid exceeding the upper limit temperature or the upper limit temperature. It may be set.

Further, the control device 6 executes control for each power conversion device 4. The control device 6 may be configured by a computer. That is, it includes a CPU (processor) (not shown) and a storage unit such as a ROM or RAM. Then, the CPU operates (data calculation, etc.) according to the instruction of the program loaded in the memory (main storage device) to execute the above control.

In the embodiment shown in FIG. 1, the temperature measuring unit 62 is a thermocouple and is installed in the center of the power generation chamber 215 of the fuel cell cartridge 203, which will be described later, to measure the temperature of each. Further, the temperature measured by each fuel cell cartridge 203 is input to the control device 6 by being connected to, for example, a plurality of temperature measuring units 62. Then, as shown in FIG. 4A, the control device 6 controls the load of each power conversion device so that the temperature of the measured temperature of each fuel cell cartridge 203 becomes the specified temperature Tc. More specifically, the control device 6 positions the load of the power conversion device 4 provided on the fuel cell cartridge 203 located on the end side of the pressure vessel 205 at the center of the pressure vessel 205. , The load is smaller than the load of the power conversion device 4 provided for the fuel cell cartridge 203.

The horizontal axis (No.) in FIG. 4A indicates each fuel cell cartridge 203, and the vertical axis corresponds to the temperature. As shown in FIG. 4A, the temperatures of the total of 20 fuel cell cartridges 203 included in the fuel cell power generation system 1 are constant under the control of the control device 6. As a result, as shown in FIG. 4B, the currents of the first (No. 1) and 20th (No. 20) fuel cell cartridges 203 located at both ends of the pressure vessel 205 are different (No. 2 to No. 2 to). It is higher than No. 19), and the current is higher by that amount, and the power generation performance is improved.

According to the above configuration, the output power of each power conversion device 4 is adjusted so that the temperature of each fuel cell unit 3 becomes the specified temperature Tc. Thereby, when the output of the fuel cell cartridge 203 becomes higher as the temperature is higher, the output performance of the fuel cell power generation system 1 can be improved.

Hereinafter, the configurations of the fuel cell cartridge 203 and the fuel cell module 201 will be described in detail with reference to FIGS. 7 to 9.

In the following, for convenience of explanation, the positional relationship of each component described using the expressions “upper” and “lower” with respect to the paper surface indicates the vertically upper side and the vertically lower side, respectively. Further, in the present embodiment, the one that can obtain the same effect in the vertical direction and the horizontal direction is not necessarily limited to the vertical vertical direction on the paper surface, but may correspond to the horizontal direction orthogonal to the vertical direction, for example. Good.
Further, in the following, a cylindrical (cylindrical) cell stack will be described as an example of the solid oxide fuel cell (SOFC) cell stack, but this is not necessarily the case, and for example, a flat cell stack. May be good. The fuel cell is formed on the substrate, but the electrode (fuel electrode or air electrode) is formed thicker instead of the substrate, and the substrate may also be used.

First, a cylindrical cell stack using a substrate tube will be described as an example of the present embodiment with reference to FIG. 7. When the base tube is not used, for example, the fuel electrode may be formed thick and the base tube may also be used, and the use of the base tube is not limited. Further, although the substrate tube in the present embodiment will be described using a cylindrical shape, the substrate tube may be tubular, and the cross section is not necessarily limited to a circular shape, and may be, for example, an elliptical shape. A cell stack such as a flat cylinder in which the peripheral side surface of the cylinder is vertically crushed may be used. Here, FIG. 7 shows an aspect of the cell stack 101 according to the embodiment of the present invention. As an example, the cell stack 101 includes a cylindrical base tube 103, a plurality of fuel cell 105 formed on the outer peripheral surface of the base tube 103, and an interconnector 107 formed between adjacent fuel cell 105. .. The fuel cell 105 is formed by laminating a fuel electrode 109, a solid electrolyte membrane 111, and an air electrode 113. Further, the cell stack 101 is attached to the air electrode 113 of the fuel cell 105 formed at one end of the plurality of fuel cell 105 formed on the outer peripheral surface of the base tube 103 in the axial direction of the base tube 103. A lead film 115 electrically connected via an interconnector 107 is provided, and a lead film 115 electrically connected to a fuel pole 109 of a fuel cell 105 formed at the other end of the end is provided.

Substrate tube 103 is made of a porous material, for example, CaO-stabilized _ZrO 2 (CSZ), a mixture of CSZ and nickel oxide (NiO) (CSZ + NiO) , or _Y 2 _{O 3} stabilized _ZrO 2 (YSZ), or The main component is _{MgAl 2} O _{4 and the like.} The base tube 103 supports the fuel cell 105, the interconnector 107, and the lead film 115, and the fuel gas supplied to the inner peripheral surface of the base tube 103 is supplied to the inner peripheral surface of the base tube 103 through the pores of the base tube 103. It is diffused in the fuel electrode 109 formed on the outer peripheral surface of the above.

The fuel electrode 109 is composed of an oxide of a composite material of Ni and a zirconia-based electrolyte material, and for example, Ni / YSZ is used. The thickness of the fuel electrode 109 is 50 μm to 250 μm, and the fuel electrode 109 may be formed by screen printing the slurry. In this case, in the fuel electrode 109, Ni, which is a component of the fuel electrode 109, has a catalytic action on the fuel gas. This catalytic action reacts a fuel gas supplied via the substrate tube 103, for example, _{a mixed gas of methane (CH 4} ) and water vapor, and _{reforms it into hydrogen (H 2} ) and carbon monoxide (CO). It is a thing. Further, in the fuel electrode 109, hydrogen (H ₂ ^{) and carbon monoxide (CO) obtained by reforming and oxygen ions (O 2-} ) supplied via the solid electrolyte membrane 111 are combined with the solid electrolyte membrane 111. _{Water (H 2} O) and carbon dioxide (CO ₂ ) are produced by electrochemical reaction in the vicinity of the interface between the two. At this time, the fuel cell 105 generates electricity by the electrons emitted from the oxygen ions.
The fuel gases that can be supplied and used for the fuel electrode 109 of the solid oxide fuel cell include _{hydrocarbon gases such as hydrogen (H 2} ), carbon monoxide (CO), and methane (CH ₄ ), city gas, and natural gas. In addition, gasification gas produced by gasifying equipment for carbon-containing raw materials such as petroleum, methanol, and coal can be mentioned.

As the solid electrolyte membrane 111, YSZ having airtightness that makes it difficult for gas to pass through and high oxygen ion conductivity at high temperature is mainly used. The solid electrolyte membrane 111 ^{moves oxygen ions (O 2-} ) generated at the air electrode to the fuel electrode. The film thickness of the solid electrolyte film 111 located on the surface of the fuel electrode 109 is 10 μm to 100 μm, and the solid electrolyte film 111 may be formed by screen printing the slurry.

The air electrode 113 is composed of, for example, a LaSrMnO _3- based oxide or a LaCoO _3- based oxide, and the air electrode 113 is coated with a slurry by screen printing or using a dispenser. The air electrode 113 dissociates oxygen in an oxidizing gas such as air to be supplied in the vicinity of the interface with the solid electrolyte membrane 111 to generate ^{oxygen ions (O 2-).}
The air electrode 113 may have a two-layer structure. In this case, the air electrode layer (air electrode intermediate layer) on the solid electrolyte membrane 111 side is made of a material showing high ionic conductivity and excellent catalytic activity. The air electrode layer (air electrode conductive layer) on the air electrode intermediate layer may be composed of a perovskite-type oxide represented by _{Sr and Ca-doped LaMnO 3.} By doing so, the power generation performance can be further improved.
The oxidizing gas is a gas containing approximately 15% to 30% of oxygen, and air is typically preferable. However, in addition to air, a mixed gas of combustion exhaust gas and air, a mixed gas of oxygen and air, etc. Can be used.

The interconnector 107 is _{composed of a conductive perovskite-type oxide represented by M 1-x} L _x TiO ₃ (M is an alkaline earth metal element and L is a lanthanoid element) such as _{SrTiO 3 system, and screen prints a slurry.} To do. The interconnector 107 has a dense film so that the fuel gas and the oxidizing gas do not mix with each other. Further, the interconnector 107 has stable durability and electrical conductivity in both an oxidizing atmosphere and a reducing atmosphere. In the adjacent fuel cell 105, the interconnector 107 electrically connects the air electrode 113 of one fuel cell 105 and the fuel electrode 109 of the other fuel cell 105, and the adjacent fuel cell 105 are connected to each other. Are connected in series.

Since the lead film 115 needs to have electron conductivity and a coefficient of thermal expansion close to that of other materials constituting the cell stack 101, Ni such as Ni / YSZ and a zirconia-based electrolyte material are used. It is composed of M1-xLxTiO ₃ (M is an alkaline earth metal element and L is a lanthanoid element) such as a composite material and SrTiO _{3 system.} The lead film 115 derives the DC power generated by the plurality of fuel cell 105s connected in series by the interconnector 107 to the vicinity of the end portion of the cell stack 101.

Next, the SOFC module and the SOFC cartridge according to the present embodiment will be described with reference to FIGS. 8 and 9. Here, FIG. 8 shows one aspect of the SOFC module according to the embodiment of the present invention. Further, FIG. 9 shows a cross-sectional view of one aspect of the SOFC cartridge according to the embodiment of the present invention, and the upper portion shown corresponds to FIG.

As shown in FIG. 8, the SOFC module (corresponding to the above fuel cell module 201) 201 accommodates, for example, a plurality of SOFC cartridges (corresponding to the above fuel cell cartridge 203) 203 and the plurality of SOFC cartridges 203. A pressure vessel 205 is provided. Although FIG. 8 illustrates a cylindrical SOFC cell stack 101, this is not necessarily the case, and a flat cell stack may be used, for example. Further, the SOFC module 201 includes a fuel gas supply pipe 207, a plurality of fuel gas supply branch pipes 207a, a fuel gas discharge pipe 209, and a plurality of fuel gas discharge branch pipes 209a. Further, the SOFC module 201 includes an oxidizing gas supply pipe (not shown), an oxidizing gas supply branch pipe (not shown), an oxidizing gas discharge pipe (not shown), and a plurality of oxidizing gas discharge branch pipes (not shown). And.

The fuel gas supply pipe 207 is provided outside the pressure vessel 205, is connected to a fuel gas supply unit that supplies fuel gas having a predetermined gas composition and a predetermined flow rate according to the amount of power generated by the SOFC module 201, and a plurality of fuel gas supply pipes 207. It is connected to the fuel gas supply branch pipe 207a. The fuel gas supply pipe 207 branches and guides a predetermined flow rate of fuel gas supplied from the above-mentioned fuel gas supply unit to a plurality of fuel gas supply branch pipes 207a. Further, the fuel gas supply branch pipe 207a is connected to the fuel gas supply pipe 207 and is also connected to a plurality of SOFC cartridges 203. The fuel gas supply branch pipe 207a guides the fuel gas supplied from the fuel gas supply pipe 207 to the plurality of SOFC cartridges 203 at a substantially equal flow rate, and substantially equalizes the power generation performance of the plurality of SOFC cartridges 203. ..

The fuel gas discharge branch pipe 209a is connected to a plurality of SOFC cartridges 203 and is also connected to the fuel gas discharge pipe 209. The fuel gas discharge branch pipe 209a guides the exhaust fuel gas discharged from the SOFC cartridge 203 to the fuel gas discharge pipe 209. Further, the fuel gas discharge pipe 209 is connected to a plurality of fuel gas discharge branch pipes 209a, and a part of the fuel gas discharge pipe 209 is arranged outside the pressure vessel 205. The fuel gas discharge pipe 209 guides the exhaust fuel gas led out from the fuel gas discharge branch pipe 209a at a substantially equal flow rate to the outside of the pressure vessel 205.

Since the pressure vessel 205 is operated at an internal pressure of 0.1 MPa to about 3 MPa and an internal temperature of atmospheric temperature to about 550 ° C., it has a proof stress and corrosion resistance against an oxidizing agent such as oxygen contained in an oxidizing gas. The material you have is used. For example, a stainless steel material such as SUS304 is suitable.

Here, in the present embodiment, a mode in which a plurality of SOFC cartridges 203 are assembled and stored in the pressure vessel 205 will be described, but the present invention is not limited to this, and for example, the SOFC cartridge 203 is not assembled and the pressure is increased. It can also be stored in the container 205.

As shown in FIG. 9, the SOFC cartridge 203 includes a plurality of cell stacks 101, a power generation chamber 215, a fuel gas supply header 217, a fuel gas discharge header 219, an oxidizing gas (air) supply header 221 and an oxidizing property. It includes a gas discharge header 223. Further, the SOFC cartridge 203 includes an upper tube plate 225a, a lower tube plate 225b, an upper heat insulating body 227a, and a lower heat insulating body 227b. In the present embodiment, in the SOFC cartridge 203, the fuel gas supply header 217, the fuel gas discharge header 219, the oxidizing gas supply header 221 and the oxidizing gas discharge header 223 are arranged as shown in FIG. The structure is such that the fuel gas and the oxidizing gas flow opposite to the inside and the outside of the cell stack 101, but this is not always necessary, for example, the inside and the outside of the cell stack 101 flow in parallel. , Or the oxidizing gas may flow in a direction orthogonal to the longitudinal direction of the cell stack 101.

The power generation chamber 215 is a region formed between the upper heat insulating body 227a and the lower heat insulating body 227b. The power generation chamber 215 is a region in which the fuel cell 105 of the cell stack 101 is arranged, and is a region in which the fuel gas and the oxidizing gas are electrochemically reacted to generate electricity. Further, the temperature in the vicinity of the central portion of the cell stack 101 in the longitudinal direction of the power generation chamber 215 is monitored by the temperature measuring unit 62 (temperature sensor, thermocouple, etc.), and is approximately 700 ° C. to higher during steady operation of the fuel cell module 201. It becomes a high temperature atmosphere of 1000 ° C.

The fuel gas supply header 217 is an area surrounded by the upper casing 229a and the upper pipe plate 225a of the SOFC cartridge 203, and the fuel gas supply branch pipe 207a is provided by the fuel gas supply hole 231a provided in the upper part of the upper casing 229a. Is communicated with. Further, the plurality of cell stacks 101 are joined by an upper pipe plate 225a and a seal member 237a (seal ring), and the fuel gas supply header 217 is supplied from the fuel gas supply branch pipe 207a through the fuel gas supply hole 231a. The fuel gas to be produced is guided into the base pipes 103 of the plurality of cell stacks 101 at a substantially uniform flow rate, and the power generation performance of the plurality of cell stacks 101 is substantially made uniform.

The fuel gas discharge header 219 is an area surrounded by the lower casing 229b and the lower pipe plate 225b of the SOFC cartridge 203, and the fuel gas discharge branch pipe 209a (not shown) is provided by the fuel gas discharge hole 231b provided in the lower casing 229b. Is communicated with. Further, the plurality of cell stacks 101 are joined to the lower pipe plate 225b by the seal member 237b, and the fuel gas discharge header 219 passes through the inside of the base pipe 103 of the plurality of cell stacks 101 and the fuel gas discharge header 219. The exhaust fuel gas supplied to the fuel gas is collected and guided to the fuel gas discharge branch pipe 209a through the fuel gas discharge hole 231b.

Corresponding to the amount of power generated by the SOFC module 201, an oxidizing gas having a predetermined gas composition and a predetermined flow rate is branched into an oxidizing gas supply branch pipe and supplied to a plurality of SOFC cartridges 203. The oxidizing gas supply header 221 is a region surrounded by the lower casing 229b, the lower tube plate 225b, and the lower heat insulating body 227b of the SOFC cartridge 203, and is provided by the oxidizing gas supply hole 233a provided on the side surface of the lower casing 229b. , It is communicated with an oxidizing gas supply branch pipe (not shown). The oxidizing gas supply header 221 generates a predetermined flow rate of oxidizing gas supplied from an oxidizing gas supply branch pipe (not shown) through the oxidizing gas supply hole 233a through the oxidizing gas supply gap 235a described later. It leads to room 215.

The oxidizing gas discharge header 223 is a region surrounded by the upper casing 229a, the upper pipe plate 225a, and the upper heat insulating body 227a of the SOFC cartridge 203, and is provided by the oxidizing gas discharge holes 233b provided on the side surface of the upper casing 229a. , It communicates with an oxidizing gas discharge branch pipe (not shown). The oxidizing gas discharge header 223 transfers the oxidative gas supplied from the power generation chamber 215 to the oxidative gas discharge header 223 via the oxidative gas discharge gap 235b, which will be described later, through the oxidative gas discharge hole 233b. It leads to an oxidizing gas discharge branch pipe (not shown).

In the upper casing 225a, the upper casing 229a is provided so that the top plate of the upper casing 229a and the top plate of the upper casing 229a and the upper heat insulating body 227a are substantially parallel to each other between the top plate of the upper casing 229a and the upper heat insulating body 227a. It is fixed to the side plate of. Further, the upper tube plate 225a has a plurality of holes corresponding to the number of cell stacks 101 provided in the SOFC cartridge 203, and the cell stacks 101 are inserted into the holes, respectively. The upper tube plate 225a airtightly supports one end of the plurality of cell stacks 101 via one or both of the sealing member 237a and the adhesive member, and also provides a fuel gas supply header 217 and an oxidizing gas discharge header. It isolates from 223.

The upper heat insulating body 227a is arranged at the lower end of the upper casing 229a so that the upper heat insulating body 227a, the top plate of the upper casing 229a, and the upper tube plate 225a are substantially parallel to each other, and is fixed to the side plate of the upper casing 229a. There is. Further, the upper heat insulating body 227a is provided with a plurality of holes corresponding to the number of cell stacks 101 provided in the SOFC cartridge 203. The diameter of this hole is set to be larger than the outer diameter of the cell stack 101. The upper heat insulating body 227a includes an oxidizing gas discharge gap 235b formed between the inner surface of the hole and the outer surface of the cell stack 101 inserted through the upper heat insulating body 227a.

The upper heat insulating body 227a separates the power generation chamber 215 and the oxidizing gas discharge header 223, and the atmosphere around the upper pipe plate 225a becomes high in temperature, resulting in a decrease in strength and corrosion by the oxidizing agent contained in the oxidizing gas. Suppress the increase. The upper tube plate 225a and the like are made of a metal material having high temperature durability such as Inconel, but the upper tube plate 225a and the like are exposed to the high temperature in the power generation chamber 215 and the temperature difference in the upper tube plate 225a and the like becomes large. It prevents thermal deformation. Further, the upper heat insulating body 227a guides the oxidative gas that has passed through the power generation chamber 215 and exposed to high temperature to the oxidative gas discharge header 223 by passing through the oxidative gas discharge gap 235b.

According to the present embodiment, due to the structure of the SOFC cartridge 203 described above, the fuel gas and the oxidizing gas flow toward the inside and the outside of the cell stack 101. As a result, the oxidative gas exchanges heat with the fuel gas supplied to the power generation chamber 215 through the inside of the base tube 103, and the upper tube plate 225a and the like made of a metal material buckle and the like. It is cooled to a temperature at which it does not deform and is supplied to the oxidizing gas discharge header 223. Further, the fuel gas is heated by heat exchange with the oxidative gas discharged from the power generation chamber 215 and supplied to the power generation chamber 215. As a result, the fuel gas preheated to a temperature suitable for power generation can be supplied to the power generation chamber 215 without using a heater or the like.

The lower tube plate 225b is attached to the side plate of the lower casing 229b so that the bottom plate of the lower tube plate 225b, the bottom plate of the lower casing 229b, and the lower insulation body 227b are substantially parallel to each other between the bottom plate of the lower casing 229b and the lower heat insulating body 227b. It is fixed. Further, the lower tube plate 225b has a plurality of holes corresponding to the number of cell stacks 101 provided in the SOFC cartridge 203, and the cell stacks 101 are inserted into the holes, respectively. The lower tube plate 225b airtightly supports the other end of the plurality of cell stacks 101 via one or both of the sealing member 237b and the adhesive member, and also provides a fuel gas discharge header 219 and an oxidizing gas supply header. It is intended to isolate 221.

The lower heat insulating body 227b is arranged at the upper end of the lower casing 229b so that the bottom plate of the lower heat insulating body 227b, the bottom plate of the lower casing 229b, and the lower pipe plate 225b are substantially parallel to each other, and is fixed to the side plate of the lower casing 229b. .. Further, the lower heat insulating body 227b is provided with a plurality of holes corresponding to the number of cell stacks 101 provided in the SOFC cartridge 203. The diameter of this hole is set to be larger than the outer diameter of the cell stack 101. The lower heat insulating body 227b includes an oxidizing gas supply gap 235a formed between the inner surface of the hole and the outer surface of the cell stack 101 inserted through the lower heat insulating body 227b.

The lower heat insulating body 227b separates the power generation chamber 215 and the oxidizing gas supply header 221, and the atmosphere around the lower tube plate 225b becomes high in temperature, resulting in a decrease in strength and corrosion by the oxidizing agent contained in the oxidizing gas. Suppress the increase. The lower tube plate 225b or the like is made of a metal material having high temperature durability such as Inconel, but the lower tube plate 225b or the like is exposed to a high temperature and the temperature difference in the lower tube plate 225b or the like becomes large, so that the lower tube plate 225b or the like is thermally deformed. It is something to prevent. Further, the lower heat insulating body 227b guides the oxidizing gas supplied to the oxidizing gas supply header 221 to the power generation chamber 215 through the oxidizing gas supply gap 235a.

According to the present embodiment, due to the structure of the SOFC cartridge 203 described above, the fuel gas and the oxidizing gas flow toward the inside and the outside of the cell stack 101. As a result, the exhaust fuel gas that has passed through the inside of the base pipe 103 and passed through the power generation chamber 215 is heat-exchanged with the oxidizing gas supplied to the power generation chamber 215, and the lower pipe plate 225b made of a metal material is exchanged. Etc. are cooled to a temperature at which deformation such as buckling does not occur and supplied to the fuel gas discharge header 219. Further, the oxidizing gas is heated by heat exchange with the exhaust fuel gas and supplied to the power generation chamber 215. As a result, the oxidizing gas heated to the temperature required for power generation can be supplied to the power generation chamber 215 without using a heater or the like.

The DC power generated in the power generation chamber 215 is led out to the vicinity of the end of the cell stack 101 by a lead film 115 made of Ni / YSZ or the like provided in the plurality of fuel cell 105, and then the current collecting rod of the SOFC cartridge 203 (not). Electric power is collected through a current collecting plate (not shown) on the (shown), and is taken out to the outside of each SOFC cartridge 203. The DC power derived to the outside of the SOFC cartridge 203 by the current collector rod connects the generated power of each SOFC cartridge 203 to a predetermined number of series and parallel numbers, and is led out to the outside of the SOFC module 201. It is converted into a predetermined AC power by a power conversion device (inverter or the like) such as a power conditioner (not shown), and is supplied to a power supply destination 7 (for example, a load facility or a power system).

The present invention is not limited to the above-described embodiment, and includes a modified form of the above-described embodiment and a combination of these embodiments as appropriate.

(Additional note)
(1) The fuel cell power generation system (1) according to at least one embodiment of the present invention is
A fuel cell power generation system (1) having a plurality of fuel cell cartridges (203).
A plurality of fuel cell units composed of two or more cell groups (G) each formed as a minimum unit of electric output by a part of a plurality of cell stacks (101) built in the fuel cell cartridge (203). (3) and
A plurality of power conversion devices (4) for converting the output power of the fuel cell unit (3), which are provided for each of the plurality of fuel cell units (3), are provided.
In the fuel cell unit (3), the two or more cell groups (G) are connected in series.

According to the configuration of the above (1), the fuel cell power generation system (1) includes a plurality of fuel cell cartridges (203), and a plurality of cell stacks (101) built in each fuel cell cartridge (203). Is grouped into a plurality of cell groups (G), which is the minimum unit of electric output. The fuel cell unit (3) is composed of two or more of such cell groups (G), and each fuel cell unit (3) is provided with a power conversion device (4) (power conditioner, etc.). By doing so, it is configured to perform power conversion for each fuel cell unit (3). Then, all the cell groups (G) belonging to each fuel cell unit (3) are connected in series.

As a result, even if a trouble such as a failure occurs in any of the plurality of power conversion devices (4) and the fuel cell cartridge (203), the remaining power conversion device (4) and the remaining fuel cell cartridge (remaining fuel cell cartridge) ( The power from the fuel cell unit (3) configured by 203) can be output to the power supply destination (7) such as the power system, and the system can be made redundant, so that the fuel is highly reliable. A battery power generation system (1) can be provided. For example, when one power conversion device (4) is provided for the fuel cell module (201) (when there is only one electric system), if the power conversion device (4) fails, the fuel cell power generation system (1) ) Will not be able to output, but according to the above configuration, the fuel cell power generation system (1) will be able to continue the power supply. Further, the output current output from each fuel cell unit (3) can be reduced as compared with the case where each fuel cell cartridge (203) is connected in series (see FIG. 6). Therefore, it is possible to reduce the current collection loss by such a low current, and it is also possible to reduce the power transmission loss by using a thinner wiring.

Further, by providing the power conversion device (4) for each fuel cell unit (3) as described above, it is possible to adopt a general-purpose low-priced power conversion device (4) for, for example, for photovoltaic power generation. .. Therefore, it is not necessary to prepare a power conversion device (4) capable of power conversion of all the fuel cell cartridges (203) provided in the fuel cell power generation system (1) by custom-ordering, and as compared with the case of FIG. The fuel cell power generation system (1) can be constructed at a lower cost.

(2) In some embodiments, in the configuration of (1) above,
The fuel cell unit (3) is composed of the cell group (G) included in one or more fuel cell cartridges (203).

According to the configuration of (2) above, for example, one fuel cell unit (3) is configured by the cell group (G) of one or a plurality of fuel cell cartridges (203). Thereby, the cell groups (G) included in the fuel cell unit (3) can be set to a desired number. Although the number (number of divisions) of cell groups (G) that can be provided in the fuel cell cartridge (203) is limited, fuel can be fueled by using the cell groups (G) of one or more fuel cell cartridges (203). By assembling the battery unit (3), the fuel cell unit (3) can be increased in voltage within a desired range. Therefore, the number of cell groups (G) possessed by the fuel cell unit (3) can be set according to the operating point of the connected power conversion device (4), so that general-purpose low-cost power conversion can be performed. The device (4) can be adopted, and the fuel cell power generation system (1) can be constructed at a lower cost.

(3) In some embodiments, in the above configurations (1) and (2),
The number of the cell groups (G) constituting the fuel cell unit (3) is an even number.
According to the configuration of (3) above, the power extraction unit from the fuel cell cartridge (203) can be unified to either the upper part or the lower part of the fuel cell cartridge (203) to facilitate the construction. Can be done.

(4) In some embodiments, in the configurations (1) to (3) above,
A power output circuit (5) capable of outputting at least a part of the output power output by the plurality of power converters (4) to the power supply destination (7) is further provided.
The power output circuit (5) has a plurality of switches (51) capable of switching the connection state between the plurality of power conversion devices (4) and the power supply destination (7).

According to the configuration of (4) above, the connection between each of the plurality of power converters (4) and the power supply destination (7) can be individually disconnected by the switch (51) of the power output circuit (5). It has become. As a result, the fuel cell unit (3) in which the failure has occurred can be easily separated. Therefore, the remaining fuel cell unit (3) can be used to continue supplying power to the power supply destination (7), and maintenance work such as replacement and repair of the failed fuel cell unit (3) can be facilitated. Can be planned.

(5) In some embodiments, in the configurations (1) to (4) above,
A plurality of temperature detecting means for detecting the temperature of each of the plurality of fuel cell cartridges (203), and
A control device (6) configured to control the output of each of the plurality of power conversion devices (4) so that the temperature of each of the plurality of fuel cell cartridges (203) becomes a specified temperature (Tc). , Further prepared.

According to the configuration of (5) above, the output power of each power converter (4) is adjusted so that the temperature of each fuel cell unit (3) becomes the specified temperature (Tc). Thereby, when the output of the fuel cell cartridge (203) becomes higher as the temperature is higher, the output performance of the fuel cell power generation system (1) can be improved.

(6) In some embodiments, in the configuration of (5) above,
The control device (6) is configured to control the output of each of the plurality of power conversion devices (4) by adjusting the load of the power conversion device (4).
According to the configuration of (6) above, by adjusting the load of each power conversion device (4), the temperature of each fuel cell unit (3) can be controlled to be a specified temperature (Tc).

(7) In some embodiments, in the configuration of (6) above,
The control device (6) is a power conversion device (6) provided for the fuel cell cartridge (203) located on the end side of a pressure vessel (205) accommodating the plurality of fuel cell cartridges (203). The load of 4) is configured to be smaller than that located at the center of the pressure vessel (205).

According to the configuration of (7) above, the load of each power conversion device is adjusted in consideration of the difference in heat dissipation in the pressure vessel (205). Thereby, the temperature of each of the plurality of fuel cell cartridges (203) can be controlled to be the specified temperature (Tc).

1 Fuel cell power generation system 3 Fuel cell unit 4 Power conversion device 41 1st wiring 42 2nd wiring 43 3rd wiring 5 Power output circuit 51 Switch 52 Boost transformer 6 Control device 62 Temperature measuring unit 7 Power supply destination 101 Cell stack 103 Base Pipe 105 Fuel cell cell 107 Interconnector 109 Fuel pole 111 Solid electrolyte membrane 113 Air pole 115 Lead membrane 201 Fuel cell module (SOFC module)
203 Fuel cell cartridge (SOFC cartridge)
205 Pressure vessel 207 Fuel gas supply pipe 207a Fuel gas supply branch pipe 209 Fuel gas discharge pipe 209a Fuel gas discharge branch pipe 215 Power generation room 217 Fuel gas supply header 219 Fuel gas discharge header 221 Oxidizing gas supply header 223 Oxidizing gas discharge header 225a Upper tube plate 225b Lower tube plate 227a Upper heat insulating body 227b Lower heat insulating body 229 Casing 229a Upper casing 229b Lower casing 231a Fuel gas supply hole 231b Fuel gas discharge hole 233a Oxidizing gas supply hole 233b Oxidizing gas discharge hole 235a Oxidizing gas Supply gap 235b Oxidizing gas discharge gap

237a Seal member

237b Seal member 241 Current collector plate 242 Current collector rod G Cell group Tc Specified temperature

Claims

A fuel cell power generation system having multiple fuel cell cartridges.
A plurality of fuel cell units composed of two or more cell groups each formed as a minimum unit of electric output by a plurality of cell stacks built in the fuel cell cartridge, and a plurality of fuel cell units.
A plurality of power conversion devices for converting the output power of the fuel cell unit, which are provided for each of the plurality of fuel cell units, are provided.
A fuel cell power generation system in which the two or more cell groups are connected in series in the fuel cell unit.
The fuel cell power generation system according to claim 1, wherein the fuel cell unit is composed of the cell group included in one or more fuel cell cartridges.
The fuel cell power generation system according to claim 1 or 2, wherein the number of the cell groups constituting the fuel cell unit is an even number.
A power output circuit capable of outputting at least a part of the output power output by the plurality of power conversion devices to the power supply destination is further provided.
The fuel cell power generation system according to any one of claims 1 to 3, wherein the power output circuit has a plurality of switches capable of switching the connection state between the plurality of power conversion devices and the power supply destination. ..
A plurality of temperature detecting means for detecting the temperature of each of the plurality of fuel cell cartridges, and
Any of claims 1 to 4, further comprising a control device configured to control the output of each of the plurality of power conversion devices so that the temperature of each of the plurality of fuel cell cartridges reaches a specified temperature. The fuel cell power generation system according to item 1.
The fuel cell power generation system according to claim 5, wherein the control device is configured to control the output of each of the plurality of power conversion devices by adjusting the load of the power conversion device.
The control device positions the load of the power conversion device provided for the fuel cell cartridge located on the end side of the pressure vessel accommodating the plurality of fuel cell cartridges at the center of the pressure vessel. The fuel cell power generation system according to claim 6, which is configured to be smaller than the one to be used.