WO2024075215A1

WO2024075215A1 - Stationary fuel cell system and power generation plant

Info

Publication number: WO2024075215A1
Application number: PCT/JP2022/037282
Authority: WO
Inventors: 博之礒田; 昌弘臼田; 裕一佐藤
Original assignee: 日産自動車株式会社
Priority date: 2022-10-05
Filing date: 2022-10-05
Publication date: 2024-04-11

Abstract

This stationary fuel cell system comprises: an auxiliary machine structure including an auxiliary machine that performs a transfer of gas to and from a fuel cell stack; a power generation module comprising the fuel cell stack connected to at least one face of the auxiliary machine structure, the face found in the up/down direction; and a box-shaped frame formed by a plurality of frame members, the power generation module being disposed inside the frame. The auxiliary machine structure is coupled to a cross member that is provided to each of a pair of lateral faces opposing each other while sandwiching therebetween the power generation module in the frame.

Description

Stationary fuel cell system and power plant

The present invention relates to a stationary fuel cell system and a power generation plant.

JP2016-177883A discloses a stationary fuel cell system in which four fuel cell stacks are arranged inside a housing. Specifically, pillars extend downward from the four corners of the underside of the upper shelf, which is a rectangular plate-like member, and the four corners of the lower shelf, which is also a rectangular plate-like member, are supported by the pillars. Two fuel cell stacks are arranged on each of the upper and lower shelves, arranged in two rows and two columns when viewed from the front. In addition, a plate is provided that extends from the center of the width of the underside of the upper shelf to the center of the width of the upper surface of the lower shelf, and functions as a heat shield that separates the two fuel cell stacks arranged on the lower shelf.

For stationary fuel cell systems, it is desirable for them to be resistant to collapse even in the event of an external input such as an earthquake. This is to prevent deformation of the air and fuel gas supply pipes and bus bars for extracting electricity.

However, in the fuel cell system described in the above document, the upper and lower shelves on which the heavy fuel cell stack is placed are supported by only four pillars and one plate, leaving room for improvement in terms of preventing collapse due to external input.

The present invention aims to provide a fuel cell system and power generation plant that is less likely to collapse due to external inputs such as earthquakes.

According to one aspect of the present invention, there is provided a stationary fuel cell system comprising an auxiliary structure including auxiliary equipment for transferring gas between the fuel cell stack, a power generation module having a fuel cell stack connected to at least one of the vertical faces of the auxiliary structure, and a box-shaped frame formed of a plurality of frame members, with the power generation module disposed inside the frame. In this system, the auxiliary structure is connected to cross members provided on each of a pair of side faces of the frame that face each other across the power generation module.

FIG. 1 is a perspective view showing a schematic configuration of a stationary fuel cell system. FIG. 2 is a front view of the stationary fuel cell system. FIG. 3 is a rear view of the stationary fuel cell system. FIG. 4 is a left side view of the stationary fuel cell system. FIG. 5 is a diagram showing fuel system components of a stationary fuel cell system. FIG. 6 is a rear view of a pair of cross members and a power generation module before they are assembled. FIG. 7 is a front view of a power generation plant utilizing the fuel cell system of FIG.

Below, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing the schematic configuration of a stationary fuel cell system (hereinafter, simply referred to as a fuel cell system) 1 according to an embodiment of the present invention. FIG. 2 is a front view of the fuel cell system 1. FIG. 3 is a rear view of the fuel cell system 1. FIG. 4 is a left side view of the fuel cell system 1. FIG. 5 is a diagram showing selected fuel system components of the fuel cell system 1. In this embodiment, the height direction of the fuel cell system 1 is the up-down direction, the flow direction of the intake pipe 8 and exhaust pipe 9 described below is the left-right direction, and the direction perpendicular to the up-down direction and the left-right direction is the front-to-rear direction. In addition, with regard to the front-to-rear direction, the side where connections to the

pipes

13 and 14 of the auxiliary structure 7 described below are provided is the front (front). The left-right direction is based on a front view.

The fuel cell system 1 according to this embodiment is used for stationary purposes. The fuel cell used in the fuel cell system 1 is a solid oxide fuel cell.

The fuel cell system 1 comprises two power generation modules 2, one piping module 3, one power recovery module 4, and a frame 5 that supports these.

The power generation module 2 comprises an auxiliary structure 7, a first fuel cell stack 6A arranged on one of the vertical faces of the auxiliary structure 7, and a second fuel cell stack 6B arranged on the other face. The fuel cell stack 6 is made up of multiple unit cells stacked in the vertical direction. The vertical dimension of the first fuel cell stack 6A is greater than the vertical dimension of the second fuel cell stack 6B. In other words, the first fuel cell stack 6A has a greater number of stacked unit cells than the second fuel cell stack 6B.

When there is no need to distinguish between the first fuel cell stack 6A and the second fuel cell stack 6B, they will be referred to as fuel cell stack 6. In addition, in this embodiment, a configuration in which the fuel cell stacks 6 are arranged on both the top and bottom sides of the auxiliary structure 7 is described, but a configuration in which the fuel cell stack 6 is arranged on only one of the sides is also acceptable.

The auxiliary structure 7 is a housing that contains auxiliary equipment (e.g., a heat exchanger, a combustor, etc.) that exchanges gas with the fuel cell stack 6.

The power generation module 2 also includes a fuel injection unit 24 that injects fuel to be supplied to the fuel cell stack 6 of the power generation module 2. In this embodiment, the fuel injection unit 24 includes two fuel injection valves, but the number of fuel injection valves is not limited to this.

The piping module 3 includes an intake pipe 8 through which air to be supplied to the power generation module 2 flows, an exhaust pipe 9 through which gas exhausted from the power generation module 2 flows, a fuel pipe 11 through which fuel to be supplied to the power generation module 2 flows, and injection unit

cooling water pipes

10, 12 through which cooling water for cooling the fuel injection unit 24 flows. Note that the injection unit

cooling water pipes

10, 12 are sometimes simply referred to as "

cooling water pipes

10, 12" in the following explanation. The cooling water pipe 12 is also sometimes referred to as the inlet cooling water pipe 12, and the cooling water pipe 10 as the outlet cooling water pipe 10.

The power recovery module 4 includes a power box 19 that contains devices and wiring for recovering the power generated by the power generation module 2 and transmitting it to the power converter 43 described below, as well as devices and wiring for drawing the power required to drive auxiliary equipment from external equipment.

The frame body 5 is composed of multiple frame members, a cross member 20, and first and

second stays

21, 22, which are arranged to surround two power generation modules 2 and one piping module 3.

The two power generation modules 2 are stacked vertically inside the frame 5, with the piping module 3 disposed between them. Hereinafter, when it is necessary to distinguish between the upper and lower power generation modules 2, the upper one will be referred to as the upper power generation module 2A and the lower one as the lower power generation module 2B.

By arranging the two power generation modules 2 one on top of the other in the vertical direction, the area required for installation of the fuel cell system 1 can be made smaller than a configuration in which the two power generation modules 2 are installed on the same surface (hereinafter, also referred to as flat placement). Furthermore, in the case of flat placement, piping such as the intake pipe 8 and exhaust pipe 9 is placed between adjacent power generation modules 2, and piping branching out from there to each auxiliary structure 7 is installed. In contrast, in the fuel cell system 1 of this embodiment, the piping module 3 is placed between the power generation modules 2 that are arranged one on top of the other in the vertical direction, so that when viewed from above, the area occupied by the piping is smaller than in the case of flat placement. In other words, according to the fuel cell system 1 of this embodiment, it is possible to further reduce the area required for installation of the fuel cell system 1 having multiple power generation modules 2.

The frame 5 includes, for example, an upper portion surrounding the upper power generation module 2A, a lower portion surrounding the lower power generation module 2B, and an intermediate portion surrounding the piping module 3. The upper portion includes at least 12 frame members assembled in a box shape to surround the upper power generation module 2A, a cross member 20 arranged to cross the left and right side surfaces defined by the frame members in the front-to-rear direction, and a first stay 22 and a second stay 21 arranged to cross the front and rear side surfaces (i.e. the front and back) defined by the frame members in the left-to-right direction. The lower portion has the same configuration as the upper portion. The intermediate portion includes at least four frame members that connect the upper portion and the lower portion at a predetermined interval in the vertical direction.

In the upper power generation module 2A, the first fuel cell stack 6A is arranged above the auxiliary structure 7, and the second fuel cell stack 6B is arranged below. Hereinafter, this state is also referred to as the upright state. On the other hand, the lower power generation module 2B has the same structure as the upper power generation module 2A, but the first fuel cell stack 6A is arranged below the auxiliary structure 7, and the second fuel cell stack 6B is arranged above. In other words, the upper power generation module 2A is inverted upside down around an axis extending in the front-to-rear direction. Hereinafter, this state is also referred to as the inverted state. The part of the frame 5 surrounding the upper power generation module 2A and the part of the frame 5 surrounding the lower power generation module 2B are also in the same structure, but inverted upside down. In this way, by using two power generation modules 2 of the same structure, one in the upright state and the other in the inverted state, costs can be reduced compared to using multiple types of power generation modules 2. Furthermore, by using the same structure on the top and bottom, the same shapes and dimensions can be used for each pipe and wire between the piping module 3 and the power generation module 2, which also reduces costs.

The two power generation modules 2 are arranged at a position where the central axis Cm in the fore-and-aft direction is offset toward the rear side with respect to the central axis Cf in the fore-and-aft direction of the frame body 5 (see Figure 4). The power generation modules 2 are fixedly supported by a pair of cross members 20 provided on the right and left sides of the frame body 5 and a first stay 22 provided on the rear side of the frame body 5. The cross members 20 connect a pair of frame members that extend in the vertical direction out of the frame members that define the left and right sides of the frame body. The first stay 22 connects a pair of frame members that define the rear side of the frame body 5. The method of fixing the power generation modules 2 to the frame body 5 will be described later.

All of the pipes in the pipe module 3 are arranged so that the flow paths are oriented in the left-right direction of the frame body 5. The intake pipe 8 and exhaust pipe 9 are supported by the frame body 5 via stays (not shown) or the like. The fuel pipe 11 and the cooling

water pipes

10 and 12 are supported by brackets 25 provided on the frame body 5.

Flanges are provided on both the left and right ends of the intake pipe 8 and the exhaust pipe 9. As described below, when connecting multiple fuel cell systems 1 in the left and right direction, these flanges are fastened with bolts or the like.

The fuel pipe 11 and the cooling

water pipes

10, 12 are provided with ribs (not shown) on both ends. When connecting multiple fuel cell systems 1 in the left-right direction, the fuel pipes 11 and the cooling

water pipes

10, 12 of adjacent fuel cell systems 1 are connected to each other via rubber pipes (not shown) or the like.

The intake pipe 8 and the power generation module 2 are connected via an intake branch pipe 13. More specifically, the intake branch pipe 13 branched off from the intake pipe 8 is connected to an intake port 7A provided in the auxiliary structure 7.

The exhaust pipe 9 and the power generation module 2 are connected via an exhaust branch pipe 14. More specifically, the exhaust branch pipe 14 branched off from the exhaust pipe 9 is connected to an exhaust port 7B provided in the auxiliary structure 7.

As described above, the upper power generation module 2A is in an upright position, and the lower power generation module 2B is in an inverted position, with the piping module 3 disposed between the two power generation modules 2. As a result, for both power generation modules 2, the second fuel cell stack 6B, which has a shorter vertical dimension than the first fuel cell stack 6A, is disposed closer to the piping module 3. In other words, the distance from the piping module 3 to each auxiliary structure 7 is shorter than when the upper power generation module 2A is in an inverted position and the lower power generation module 2B is in an upright position.

The intake port 7A and exhaust port 7B are located on the front side of the auxiliary structure 7 when viewed from above. Also, as described above, the power generation module 2 is offset toward the rear side of the frame body 5. Therefore, the distance between the intake port 7A and exhaust port 7B and the frame body 5 is secured, and there is ample space for the intake branch pipe 13 and exhaust branch pipe 14 to be handled.

Furthermore, if either the intake port 7A or the exhaust port 7B is located on the rear side of the auxiliary structure 7 when viewed from above, the amount by which the power generation module 2 can be offset to the rear side is limited by the presence of piping connected thereto. As a result, void space is generated on the front and rear sides. On the other hand, in the fuel cell system 1 of this embodiment, the intake port 7A and the exhaust port 7B are concentrated on the front side, so the rear side of the power generation module 2 can be brought closer to the rear side of the frame body 5. In other words, according to this embodiment, the void space (IS in FIG. 4) generated between the rear side of the frame body 5 and the rear side of the power generation module 2 can be made smaller.

In addition, in the upper power generation module 2A, the intake port 7A is located on the left side and the exhaust port 7B is located on the right side when viewed from the front. On the other hand, in the lower power generation module 2B, the intake port 7A is located on the right side and the exhaust port 7B is located on the left side when viewed from the front. In other words, the arrangement of the intake port 7A and the exhaust port 7B is reversed between the upper power generation module 2A and the lower power generation module 2B. This allows the position of the connection part of the intake pipe 8 with the intake branch pipe 13 for the upper power generation module 2A and the connection part with the intake branch pipe 13 for the lower power generation module 2B to be shifted in the left-right direction. The intake branch pipe 13 has ancillary devices such as a control valve, a shutoff valve, and actuators that drive each valve body (none of which are shown), but by shifting the positions of the two connections in the left-right direction in this way, the positions of the ancillary devices can be dispersed, creating room for handling the two intake branch pipes 13. Also, if the two connections are located close to each other, problems such as air flowing less easily through one of the intake branch pipes 13 can occur, but by shifting the positions of the two connections left and right as described above, this problem can be solved. The same applies to the connections of the exhaust pipe 9 to the two exhaust branch pipes 14.

In this embodiment, the power generation modules 2 have the same structure, and therefore, as described above, the positions of the intake ports 7A and exhaust ports 7B are naturally reversed, as described above, since the power generation modules 2 are used in both the upright and inverted states. However, even if two power generation modules 2 with different structures are used, the positions of the intake ports 7A and exhaust ports 7B are reversed between the upper power generation module 2A and the lower power generation module 2B in order to solve the above-mentioned problem.

When the fuel cell system 1 is used in a power generation plant or the like, maintenance and inspection work is required, such as checking for leaks from each pipe and replacing consumables or defective parts. In the fuel cell system 1 of this embodiment, the power generation module 2 is offset toward the rear side of the frame 5, and the intake ports 7A and exhaust ports 7B of the upper and lower power generation modules 2 are all located on the front side, so that ancillary equipment such as shut-off valves (not shown) included in the piping module 3 can also be concentrated on the front side. Therefore, with the fuel cell system 1 of this embodiment, the amount of movement of workers during maintenance and inspection work is reduced, improving work efficiency.

Furthermore, during maintenance and inspection work, if the location of the part being worked on is low, the worker will have to bend over or even lie down. Conversely, if the location of the part being worked on is high, the worker will have to stretch or stand on a step stool. Either case will lead to poor workability. However, in the fuel cell system 1 of this embodiment, the upper power generation module 2A is upright and the lower power generation module 2B is inverted, and the piping module 3 is positioned between the two power generation modules 2. As a result, the auxiliary structure 7 of the upper and lower power generation modules 2 is positioned closer to the center of the fuel cell system 1 in the vertical direction, preventing poor workability.

The inventors' investigation revealed that deterioration of workability can be suppressed if the height of the part to be worked on from the installation surface is in the range of approximately 400 mm to 1500 mm. Therefore, although the dimensions of the power generation module 2 and the frame body 5 can be set arbitrarily, from the viewpoint of the above-mentioned workability, the dimensions of the power generation module 2 and the frame body 5 are set so that the height of the intake port 7A and exhaust port 7B of the upper and lower power generation modules 2 from the installation surface is within the range of 400 mm to 1500 mm.

The fuel injection unit 24 is fixedly supported by the second stay 21 provided on the front side of the frame 5. Fuel is supplied from the fuel pipe 11 to the fuel injection unit 24 via the fuel branch pipe 15, and from the fuel injection unit 24 to the power generation module 2 via the fuel supply pipe 26. The fuel injection unit 24 also has a cooling water gallery 27 that surrounds the injection part of the fuel injection valve. The cooling water gallery 27 and the inlet cooling water pipe 12 are connected by the first cooling water branch pipe 16, and the cooling water gallery 27 and the outlet cooling water pipe 10 are connected by the second cooling water branch pipe 17. In other words, the cooling water is supplied from the inlet cooling water pipe 12 to the cooling water gallery 27 via the first cooling water branch pipe 16, where it cools the fuel injection valve, and flows into the outlet cooling water pipe 10 via the second cooling water branch pipe 17.

The power box 19 is placed on the back of the frame body 5, between the upper and lower power generation modules 2. The power generation module 2 and the power box 19 are electrically connected via a bus bar 18. The bus bar 18 is taken out from the surface of the fuel cell stack 6 opposite the surface that contacts the auxiliary structure 7, and is connected to the power box 19 through a wiring passage 23 provided along the frame member of the frame body 5.

When two power generation modules 2 are laid flat, it is necessary to provide a space for installing the power box 19 separately from the installation space for the power generation modules 2, but with the configuration of this embodiment, this is not necessary. In other words, the area required for installing the fuel cell system 1 can be reduced.

Next, we will explain how to attach the power generation module 2 to the frame body 5 with reference to Figure 6.

Figure 6 shows the pair of cross members 20 and the power generation module 2 before assembly, viewed from the rear side. Note that at this stage, the first stay 22 has not been attached to the frame body 5.

A guide groove 33 is provided on the opposing surfaces of the pair of cross members 20, with at least the end on the rear side being an open end. The auxiliary structure 7 of the power generation module 2 is provided with a first slide portion 31 and a second slide portion 32 shaped to correspond to the guide groove 33. Note that in FIG. 6, the slide member 30 with the second slide portion 32 is made separately from the auxiliary structure 7 and attached to the auxiliary structure 7, but the second slide portion 32 may be formed integrally with the housing of the auxiliary structure 7.

Then, the rear surface of the frame body 5 is used as an insertion surface, and the power generation module 2 is moved from this insertion surface along the guide groove 33 with the first slide portion 31 and the second slide portion 32, thereby inserting the power generation module 2 into the frame body 5. After insertion, the power generation module 2 and the frame body 5 are rigidly connected using the first stay 22. This fixes the power generation module 2 to the frame body 5. At this time, if the guide groove 33 is provided from one end to the other end of the cross member 20, it is necessary to insert the power generation module 2 into the frame body 5 while checking the position of the power generation module 2, and position the power generation module 2. However, in this embodiment, the position of the front end of the guide groove 33 is aligned with the position of the first slide portion 31 when the power generation module 2 is appropriately positioned. This makes positioning easier. In addition, since the insertion surface is on the rear side and the connection parts between the auxiliary structure 7 and each piping are on the front side of the auxiliary structure 7, the power generation module 2 can be removed from the frame body 5 by releasing the connection with each piping. In other words, there is no need to remove the pipes from the frame 5 when replacing the power generation module 2, etc.

Furthermore, when the power generation module 2 is fixed to the frame body 5 as described above, the auxiliary structure 7 of the power generation module 2 in particular also functions as a structural member connecting a pair of cross members 20 provided on the left and right side surfaces of the frame body 5. The surface rigidity of the upper part of the frame body 5 is strengthened by the pair of cross members 20 on each of the left and right sides, by the second stays 21 on the front, and by the second stays 21 on the back, but the auxiliary structure 7 functions as a structural member that crosses each of the left and right sides, improving the rigidity of the upper part as a whole. The same is true for the lower part. This makes it possible to suppress deformation and collapse due to external forces such as earthquakes.

Next, a power generation plant using the fuel cell system 1 will be described with reference to FIG. 7.

Figure 7 is a front view of a power generation plant that uses the fuel cell system 1.

As shown in the figure, a plurality of fuel cell systems 1 are arranged adjacent to each other in the left-right direction, and the respective frame bodies 5 are rigidly connected to each other by bolts or the like. As a result, the pair of rigidly connected frame members function as reinforcing members to suppress deformation of the frame body 5. The intake pipes 8, exhaust pipes 9, fuel pipes 11, and cooling

water pipes

10, 12 of each fuel cell system 1 are also connected. The intake pipes 8 of adjacent fuel cell systems 1 are connected directly or via joint pipes. The same is true for the exhaust pipes 9. The fuel pipes 11 and cooling

water pipes

10, 12 of adjacent fuel cell systems 1 are connected via joint pipes (e.g., rubber pipes, etc.). As a result, the connected linear intake pipes 8, exhaust pipes 9, fuel pipes 11, and cooling

water pipes

10, 12 are arranged between the row of upper power generation modules 2A and the row of lower power generation modules 2B. The wiring contained in the power boxes 19 of adjacent fuel cell systems 1 are electrically connected.

As described above, the intake pipe 8, exhaust pipe 9, fuel pipe 11, and cooling

water pipes

10 and 12 are connected in a straight line, which reduces pressure loss compared to when there are bent sections. In addition, all of these pipes can be accessed from the front, making them easy to work with.

A second frame 40 is connected to one end (the right end in FIG. 7) in the left-right direction of a row (hereinafter also referred to as a fuel cell row) in which a plurality of fuel cell systems 1 are connected. The second frame 40 supports and fixes an intake air introduction pipe 41, one end of which is connected to the intake pipe 8, an exhaust discharge pipe 42, one end of which is connected to the exhaust pipe 9, a power converter 43, a fuel introduction pipe 45, one end of which is connected to the fuel pipe 11, a cooling water introduction pipe 44, one end of which is connected to the cooling water pipe 10, and a cooling water discharge pipe 46, one end of which is connected to the cooling water pipe 12. Hereinafter, the second frame 40, the intake air introduction pipe 41, the exhaust discharge pipe 42, the power converter 43, the fuel introduction pipe 45, the cooling water introduction pipe 44, and the cooling water discharge pipe 46 are collectively referred to as an external connection module 47.

At the other left-right end of the fuel cell row, the openings of the intake pipe 8, exhaust pipe 9, and fuel pipe 11 are closed with lids or plugs. In addition, the end of the cooling water pipe 10 and the end of the cooling water pipe 12 are connected.

The other end of the intake air introduction pipe 41 is connected to an intake system (not shown) equipped with a blower or the like, which is provided outside the fuel cell row. The other end of the exhaust outlet pipe 42 is open to the atmosphere. The other end of the exhaust outlet pipe 42 may also be connected to an exhaust treatment system (not shown) provided outside the fuel cell row.

The other end of the fuel inlet pipe 45 is connected to a fuel system (not shown) that includes a fuel tank, a pressure regulating valve, etc. The other ends of the cooling water inlet pipe 44 and the cooling water outlet pipe 46 are connected to a cooling system (not shown) that includes a cooling water tank, a circulation pump, a radiator, etc.

The power converter 43 is electrically connected to each power box 19 of the fuel cell row via power wiring. In other words, the power generated by each power generation module 2 of the fuel cell row is output via one power converter 43. By consolidating the power converter 43 into one in this way, the following effects can be obtained. First, the installation area of the power generation plant can be reduced compared to a configuration in which a power converter 43 is arranged in each fuel cell system 1. In addition, when a cooling mechanism for the power converter 43 is provided, the cooling target is one location, so the configuration of the cooling mechanism is simplified and costs can be reduced. If more fuel cell systems 1 are to be connected, a fuel cell row may be formed on the right side of the external connection module 47 in FIG. 7 in the same way as on the left side. In this case, the intake air introduction pipe 41, the exhaust discharge pipe 42, the fuel introduction pipe 45, the cooling water introduction pipe 44, and the cooling water discharge pipe 46 each branch off and are connected to the fuel cell row connected to the right side. The power wiring is similar, and the fuel cell row on the right side is also electrically connected to the power converter 43.

Next, we will explain the effects obtained by the above-mentioned fuel cell system 1 and the power generation plant using it.

The fuel cell system 1 of this embodiment is a stationary fuel cell system that includes an auxiliary structure 7 including auxiliary equipment that exchanges gas with a fuel cell stack 6, a power generation module 2 equipped with a fuel cell stack 6 connected to at least one of the vertical faces of the auxiliary structure 7, and a box-shaped frame 5 formed of multiple frame members, with the power generation module 2 disposed inside the frame 5. In this system, the auxiliary structure 7 is connected to cross members 20 provided on each of a pair of side faces of the frame 5 that face each other across the power generation module 2.

As a result, the auxiliary structure 7 also functions as a structural member connecting a pair of cross members 20 provided on the left and right sides of the frame body 5, improving the rigidity of the frame body 5 and reducing deformation and collapse due to external forces such as earthquakes.

In this embodiment, one of the sides of the frame body 5 perpendicular to either of the pair of sides on which the cross member 20 is provided is used as an insertion surface for inserting the power generation module 2 into the inside of the frame body 5, and a first stay 22 is further provided to rigidly connect the auxiliary structure 7 to a pair of opposing frame members that constitute the insertion surface. As a result, the first stay 22 functions as a structural member that increases the rigidity of the frame body 5.

In this embodiment, the second stay 21 is spanned between a pair of frame members including the first stay 22 and a pair of frame members facing each other with the power generation module 2 in between, and a fuel injection unit 24 that supplies fuel to the power generation module 2 and

pipes

10, 12 for cooling liquid that cools the fuel injection unit 24 are fixed to the second stay 21. This allows the second stay 21 to function as a structural member that increases the rigidity of the frame body 5.

In this embodiment, the power generation module 2 comprises a first fuel cell stack 6A connected to one of the vertical surfaces of the auxiliary structure 7, and a second fuel cell stack 6B connected to the other vertical surface of the auxiliary structure 7. This results in the auxiliary structure 7 being positioned in the middle of the power generation module 2 in the vertical direction. Note that "middle" here does not mean the center, but between the upper end and the lower end. As a result, the position of the cross member 20 is closer to the center of the frame member that surrounds the upper power generation module 2A and extends in the vertical direction, which makes it more effective at increasing surface rigidity. The same applies to the cross member 20 that secures the lower power generation module 2B.

According to this embodiment, a power generation plant is provided that includes multiple fuel cell systems 1. In this plant, each frame body 5 is closely arranged with the faces on which the cross members 20 are provided facing each other, and adjacent frame bodies 5 are rigidly connected to each other. This makes it possible to suppress deformation of the frame bodies 5.

　Although the embodiments of the present invention have been described above, the above embodiments merely show some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

Claims

an auxiliary structure including an auxiliary that transfers gas between the auxiliary structure and the fuel cell stack; and a power generation module including a fuel cell stack connected to at least one of the upper and lower faces of the auxiliary structure;
A box-shaped frame body formed by a plurality of frame members;
Equipped with
In a stationary fuel cell system in which the power generation module is disposed inside the frame,
A stationary fuel cell system, wherein the auxiliary structure is coupled to a cross member provided on each of a pair of opposing sides of the frame body with the power generation module in between.
2. The stationary fuel cell system according to claim 1,
one of the side surfaces of the frame body perpendicular to each of the pair of side surfaces on which the cross member is provided is defined as an insertion surface for inserting the power generation module into the inside of the frame body;
the stationary fuel cell system further comprising a first stay that rigidly connects the auxiliary structure to a pair of opposing frame members that constitute the insertion surface.
3. The stationary fuel cell system according to claim 2,
a second stay is spanned between the pair of frame members including the first stay and a pair of frame members opposed to each other with the power generation module interposed therebetween;
A fuel injection unit that supplies fuel to the power generation module and a coolant pipe that cools the fuel injection unit are fixed to the second stay.
2. The stationary fuel cell system according to claim 1,
The power generation module is a stationary fuel cell system comprising a first fuel cell stack connected to one of the vertical sides of the auxiliary structure, and a second fuel cell stack connected to the other vertical side of the auxiliary structure.
2. A power generation plant including a plurality of stationary fuel cell systems according to claim 1,
The power generation plant, wherein the frame bodies are closely arranged with the faces on which the cross members are provided adjacent to each other, and adjacent frame bodies are rigidly connected to each other.