Power generating system

Abstract

To stop power generation of a fuel cell in a case where a fuel gas leak occurs in at least one of a tank compartment and a fuel cell compartment.SOLUTION: A power generation system includes: a fuel cell compartment where a fuel cell is installed; a tank compartment where a fuel tank storing fuel is installed; and a fuel supply pipe for supplying fuel from the fuel tank to the fuel cell. The fuel supply pipe includes at least two cutoff valves, namely a tank side cutoff valve installed in the tank compartment and a fuel cell side cutoff valve installed in the fuel cell compartment. The fuel cell system further includes a fuel exhaust pipe branched from the fuel supply pipe between the tank side cutoff valve and the fuel cell side cutoff valve, and a discharge valve installed in the fuel exhaust pipe. When a fuel gas detector detects that a concentration of the fuel gas is at or above a stipulated value, the tank side cutoff valve and the fuel cell side cutoff valve are sealed, while the discharge valve is opened.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power generation system. [Background technology]

[0002] BACKGROUND ART Conventionally, a fuel cell ship has been proposed in which fuel gas (for example, hydrogen gas) is supplied from a fuel tank to a fuel cell, and a propulsion device is driven by the electricity generated by the fuel cell (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-92815 Summary of the Invention [Problem to be solved by the invention]

[0004] Fuel gas is a flammable gas. For this reason, in fuel cell ships, it may be required that the fuel tank that stores the fuel gas and the fuel cell to which the fuel gas is supplied are installed in separate compartments. The compartment in which the fuel tank is installed will be referred to as the "tank compartment" below. The compartment in which the fuel cell is installed will be referred to as the "fuel cell compartment" below. If a fuel gas leak were to occur in at least one of the tank compartment and the fuel cell compartment, it would create a dangerous situation, so some kind of countermeasure must be taken.

[0005] The present invention has been made to solve the above problems, and its purpose is to provide a power generation system that can stop fuel cell power generation in the unlikely event that a fuel gas leak occurs in at least one of the tank compartment and the fuel cell compartment. [Means for solving the problem]

[0006] A power generation system according to one aspect of the present invention is a fuel cell system that generates electricity and supplies the electricity supplied from the fuel cell to a propulsion device or onboard equipment, and includes a fuel cell compartment in which the fuel cell is installed, a tank compartment in which a fuel tank that stores the fuel is installed, and a fuel supply pipe that supplies the fuel from the fuel tank to the fuel cell, and the fuel supply pipe has at least two shut-off valves, a tank-side shut-off valve installed in the tank compartment and a fuel cell-side shut-off valve installed in the fuel cell compartment, and further includes a fuel discharge pipe that branches off from the fuel supply pipe between the tank-side shut-off valve and the fuel cell-side shut-off valve, and a release valve installed in the fuel discharge pipe, and when a fuel gas detector detects that the concentration of the fuel gas is above a standard value, the tank-side shut-off valve and the fuel cell-side shut-off valve are closed, while the release valve is opened. [Effects of the Invention]

[0007] According to the above configuration, in the unlikely event that a fuel gas leak occurs in at least one of the tank compartment and the fuel cell compartment, power generation by the fuel cell can be stopped. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is an explanatory diagram showing a schematic configuration of a fuel cell ship according to an embodiment of the present invention; [Figure 2] FIG. 2 is an explanatory diagram schematically illustrating the internal structure of the fuel cell ship. [Figure 3] 10 is a flowchart showing a processing flow according to an example of control of opening and closing of a shutoff valve of the fuel cell ship. [Figure 4] 10 is a flowchart showing a process flow according to another example of the shutoff valve opening / closing control. [Figure 5] 10 is a flowchart showing a processing flow when further control of opening and closing of a discharge valve of the fuel cell ship is performed. [Figure 6] 10 is a flowchart showing a process flow according to another example of the opening / closing control of the release valve. [Figure 7]10 is a flowchart showing a process flow according to still another example of the opening / closing control of the release valve. [Figure 8] 10 is a flowchart showing a processing flow according to an example of the opening and closing control of the shutoff valve and the release valve, taking into consideration the detection of fuel gas in the duct section of the fuel cell ship. [Figure 9] 10 is a flowchart showing a processing flow according to an example of the opening and closing control of the shutoff valve and the release valve, taking into consideration the detection of fuel gas by a gas detector inside the vent pipe of the fuel cell ship. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the present invention will be described below with reference to the drawings. In this specification, directions are defined as follows: First, the direction from the stern of a fuel cell ship toward the bow is defined as "forward," and the direction from the bow toward the stern is defined as "rearward." The lateral direction perpendicular to the fore-aft direction is defined as the left-right direction. In this case, when the fuel cell ship is moving forward, the left side as seen from the operator is defined as "left," and the right side is defined as "right." Furthermore, the upstream side of the direction of gravity perpendicular to the fore-aft and left-right directions is defined as "up," and the downstream side is defined as "down."

[0010] [1. Overview of fuel cell ship configuration] First, a fuel cell ship SH according to this embodiment will be described with reference to Figure 1. Figure 1 is an explanatory diagram showing the general configuration of the fuel cell ship SH. The fuel cell ship SH comprises a hull 1 and a cabin 2. The cabin 2 is disposed on the upper surface of the hull 1.

[0011] The fuel cell ship SH further includes a fuel cell system 3, a fuel gas storage unit 4, a battery system 5, a propulsion device 6, a plurality of peripheral devices 11, and a control device 12. In Fig. 1, control signal or high-voltage power supply lines are indicated by solid lines, and control signal or low-voltage power supply lines are indicated by dashed lines.

[0012] The fuel cell system 3 functions as a main power source. The fuel cell system 3 consumes fuel gas to generate electric power (specifically, DC power). The fuel gas is an example of a fuel, such as a combustible gas. Typically, the fuel gas is hydrogen gas. The fuel cell system 3 supplies the generated electric power to the propulsion device 6 and peripheral devices 11. The fuel cell system 3 can also supply electric power to the storage battery system 5 to charge the storage battery system 5.

[0013] The fuel gas storage unit 4 stores the fuel gas to be supplied to the fuel cell system 3. The fuel gas is supplied from the fuel gas storage unit 4 to the fuel cell system 3 via a fuel gas supply pipe 32 (see FIG. 2) which will be described later.

[0014] The storage battery system 5 has a storage battery. The storage battery is, for example, a lithium secondary battery, but may also be a nickel-cadmium storage battery, a nickel-metal hydride storage battery, or the like. The storage battery system 5 functions as an auxiliary power source that supplies stored power (specifically, DC power) to the propulsion device 6 and peripheral devices 11. In this way, the storage battery system 5 functions as an auxiliary power source, making it possible to compensate for a shortage of power supplied from the fuel cell system 3 to the propulsion device 6, etc. The storage battery system 5 may also supply power to the control device 12.

[0015] The propulsion device 6 is driven by power supplied from a fuel cell 31 (see FIG. 2 ), which will be described later, of the fuel cell system 3, and generates a propulsive force for the hull 1. In other words, the fuel cell ship SH is equipped with the propulsion device 6 that generates a propulsive force for the hull 1 using the power supplied from the fuel cell 31.

[0016] The propulsion device 6 may be driven solely by power supplied from the storage battery of the storage battery system 5, or may be driven by power supplied from both the fuel cell 31 and the storage battery. In other words, the propulsion device 6 may be driven by power supplied from at least one of the fuel cell and the storage battery to generate a propulsive force for the hull 1.

[0017] The propulsion device 6 includes a power converter 6a, a propulsion motor 6b, and a propeller 6c. The power converter 6a converts the power supplied from the fuel cell system 3 into power conforming to the specifications of the propulsion motor 6b. For example, the power converter 6a converts DC power into AC power. In this case, the power converter 6a includes, for example, an inverter. The propulsion motor 6b is driven by the power (for example, AC power) supplied from the power converter 6a. When the propulsion motor 6b is driven, the rotational force of the propulsion motor 6b is transmitted to the propeller 6c. As a result, the propeller 6c rotates, generating a propulsive force for the hull 1. Note that a marine gear may be provided between the propulsion motor 6b and the propeller 6c.

[0018] The peripheral devices 11 include, for example, compressors, electromagnetic valves, pumps, etc. The peripheral devices 11 also include electrical devices such as lighting equipment and air conditioners, but the types of the peripheral devices 11 are not particularly limited.

[0019] The control device 12 controls the fuel cell system 3, the fuel gas storage unit 4, the battery system 5, the propulsion device 6, and a plurality of peripheral devices 11. The control device 12 is configured, for example, with one or more computers. The computer is, for example, a programmable logic controller (PLC), but may also be an electronic control unit (ECU). The control device 12 is supplied with power from a battery (not shown, for example, a lead battery) or a storage battery of the battery system 5.

[0020] The control device 12 includes a control unit 12a and a memory unit 12b. The control unit 12a includes a processor such as a CPU (Central Processing Unit). The memory unit 12b includes a storage device and stores data and computer programs. Specifically, the memory unit 12b includes a main storage device such as a semiconductor memory and an auxiliary storage device such as a semiconductor memory, a solid-state drive, and / or a hard disk drive. The memory unit 12b may include removable media. The memory unit 12b corresponds to an example of a non-transitory computer-readable storage medium.

[0021] The processor of the control unit 12a controls the fuel cell system 3, the fuel gas storage unit 4, the battery system 5, the propulsion device 6, and multiple peripheral devices 11 by executing computer programs stored in the storage device of the memory unit 12b.

[0022] [2. Internal structure of fuel cell ships] Next, the internal structure of the fuel cell ship SH will be described with reference to Figure 2. Figure 2 is an explanatory diagram that schematically shows the internal structure of the fuel cell ship SH. In Figure 2, the air flow is indicated by dashed arrows. In Figure 2, each component is illustrated with the right side of the drawing as the bow side and the left side of the drawing as the stern side, but the positions of each component are not limited to those shown in Figure 2 as long as the connection relationships between each component are maintained.

[0023] The fuel cell ship SH comprises an engine room 13 and a fuel room 14. The engine room 13 and the fuel room 14 are arranged below the deck 1a of the hull 1. The engine room 13 is located on the bow side of the fuel room 14. Below the deck 1a, bulkheads W1, W2, and W3 are located in this order from the bow side to the stern side. The engine room 13 is separated from other spaces by bulkheads W1 and W2. The fuel room 14 is separated from other spaces by bulkheads W2 and W3. The bulkheads W1 to W3 are made of, for example, fiber reinforced plastics (FRP), but may also be made of steel plates.

[0024] (2-1. Configuration of fuel cell system) The fuel cell system 3 of the fuel cell ship SH is located in the engine room 13. The fuel cell system 3 has a fuel cell 31, a fuel gas supply pipe 32, and a fuel cell-side shutoff valve 33. The fuel cell-side shutoff valve 33 is an example of peripheral equipment 11 (see FIG. 1).

[0025] The fuel cell 31 generates electricity (specifically, DC power) through an electrochemical reaction between a fuel gas, which is an example of fuel, and an oxidant gas. Typically, the oxidant gas is air, and the oxidant is oxygen. In other words, the fuel cell ship SH is equipped with fuel cells 31 that generate electricity through an electrochemical reaction of fuel.

[0026] The fuel cell 31 is a fuel cell stack composed of multiple stacked cells. For example, each cell of the fuel cell 31 has a solid polymer electrolyte membrane, an anode, a cathode, and a pair of separators. The anode and cathode sandwich the solid polymer electrolyte membrane. The anode is the negative electrode (fuel electrode). The anode includes an anode catalyst layer and a gas diffusion layer. The cathode is the positive electrode (air electrode). The cathode includes a cathode catalyst layer and a gas diffusion layer. The anode, solid polymer electrolyte membrane, and cathode form a membrane electrode assembly (MEA). A pair of separators sandwich the membrane electrode assembly. Each separator has multiple grooves. Each groove in one separator forms a flow path for fuel gas. Each groove in the other separator forms a flow path for oxidant gas.

[0027] In the above-described configuration of the fuel cell 31, hydrogen contained in the fuel gas is decomposed into hydrogen ions and electrons by a catalyst on the anode side. The hydrogen ions pass through the solid polymer electrolyte membrane and move to the cathode side. Meanwhile, the electrons move through an external circuit to the cathode side. This generates current (electricity is generated). On the cathode side, oxygen contained in the oxidant gas combines with the electrons that have flowed through the external circuit and the hydrogen ions that have passed through the solid polymer electrolyte membrane to produce water. The produced water is discharged overboard via the discharge pipe 31a.

[0028] The fuel cell 31 supplies the generated power to the propulsion device 6 and peripheral devices 11 shown in Fig. 1. Note that the fuel cell 31 may also supply the generated power to the propulsion device 6 and peripheral devices 11 indirectly via a circuit such as a DC / DC converter.

[0029] The fuel gas supply pipe 32 is a fuel supply pipe for supplying fuel (e.g., fuel gas) stored in a fuel tank 41 (described later) of the fuel gas storage unit 4 to the anode of the fuel cell 31. In other words, the fuel cell ship SH is provided with the fuel gas supply pipe 32 for supplying fuel from the fuel tank 41 to the fuel cell 31.

[0030] The fuel cell-side shutoff valve 33 is an example of a shutoff valve SV that opens or closes the flow path of the fuel gas supply pipe 32. The opening and closing of the fuel cell-side shutoff valve 33 is controlled by the control unit 12a (see FIG. 1). Specifically, the fuel cell-side shutoff valve 33 switches between supplying and stopping the supply of fuel gas from the fuel tank 41 to the fuel cell 31 based on the control of the control unit 12a. Only one fuel cell-side shutoff valve 33 is provided on the fuel gas supply pipe 32 in the fuel cell compartment 30, which will be described later, but two or more may be provided.

[0031] The fuel cell ship SH further includes a fuel cell compartment 30. The fuel cell compartment 30 is a housing that houses a fuel cell 31, and is arranged in the engine room 13. In other words, the fuel cell ship SH includes the fuel cell compartment 30 in which the fuel cell 31 is installed.

[0032] The fuel cell compartment 30 has a hollow shape. For example, the fuel cell compartment 30 has a hollow, approximately rectangular parallelepiped shape. In this case, the outer walls constituting the fuel cell compartment 30 include, for example, a top wall 30a, a bottom wall 30b, a front wall (not shown), a back wall (not shown), a side wall 30c, and a side wall 30d. However, the top, bottom, front, back, and side surfaces of the fuel cell compartment 30 can be arbitrarily determined. Furthermore, the shape of the fuel cell compartment 30 is not particularly limited as long as it has a space large enough to accommodate the fuel cell 31. The fuel cell compartment 30 can also be considered as a container, chamber, or box that accommodates the fuel cell 31. The material of the outer wall of the fuel cell compartment 30 is, for example, FRP, but may also be a steel plate.

[0033] A battery compartment air inlet 30e is provided in the side wall 30d of the fuel cell compartment 30. The battery compartment air inlet 30e is connected to a battery compartment air inlet pipe 35, which will be described later. The battery compartment air inlet 30e may be provided in an outer wall of the fuel cell compartment 30 other than the side wall 30d.

[0034] Meanwhile, a battery compartment exhaust port 30f is provided in the side wall 30c of the fuel cell compartment 30. The battery compartment exhaust port 30f is in communication with a duct compartment 90, which will be described later. Note that the battery compartment exhaust port 30f may be provided in an outer wall of the fuel cell compartment 30 other than the side wall 30c.

[0035] The fuel cell compartment 30 has an internal space that is sealed except for a cell compartment air inlet 30e and a cell compartment air outlet 30f.

[0036] The fuel cell compartment 30 accommodates a portion of the fuel gas supply pipe 32 and a fuel cell-side shutoff valve 33. The fuel cell compartment 30 also accommodates a cell compartment internal gas detector 34a and a cell compartment internal fire detector 34b.

[0037] The cell compartment internal gas detector 34a is a fuel gas detector disposed inside the fuel cell compartment 30. For example, when the fuel gas is hydrogen gas, the cell compartment internal gas detector 34a is configured with a hydrogen gas detection sensor.

[0038] The battery compartment internal gas detector 34a is disposed on the inner surface of the top wall 30a located at the top of the fuel cell compartment 30. Hydrogen gas, which serves as fuel gas, is lighter than air and rises. Therefore, by disposing the battery compartment internal gas detector 34a on the top wall 30a of the fuel cell compartment 30, even if fuel gas leaks within the fuel cell compartment 30, the leaked fuel gas can be reliably detected by the battery compartment internal gas detector 34a. The battery compartment internal gas detector 34a may be located at the most downstream side of the flow path through which the fuel gas flows when the fuel gas leaks within the fuel cell compartment 30.

[0039] When the battery compartment internal gas detector 34a detects fuel gas in the fuel cell compartment 30, the detection signal is sent from the battery compartment internal gas detector 34a to the control unit 12a. This enables the control unit 12a to control the fuel cell side shutoff valve 33 provided in the fuel gas supply pipe 32 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. Details of the opening and closing control of the fuel cell side shutoff valve 33 will be described later.

[0040] The battery compartment internal fire detector 34b is a fire detector disposed inside the fuel cell compartment 30. The battery compartment internal fire detector 34b includes, for example, one or more sensors selected from a smoke sensor that detects smoke, a heat sensor that detects heat, and a flame sensor that detects flames. The battery compartment internal fire detector 34b may be configured as a thermocouple-type fire detector.

[0041] The battery compartment internal fire detector 34b is disposed on the inner surface of the top wall 30a located at the top of the fuel cell compartment 30. In the unlikely event that a fire breaks out inside the fuel cell compartment 30, the battery compartment internal fire detector 34b detects the fire and outputs a detection signal indicating the occurrence of a fire to the control unit 12a. In this case, the control unit 12a controls the fuel cell-side shutoff valve 33 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. This minimizes the risk of an explosion in the fuel cell compartment 30 due to ignition of the fuel gas.

[0042] A battery compartment air supply pipe 35 is connected to the fuel cell compartment 30. The battery compartment air supply pipe 35 extends from the battery compartment air supply port 30e of the fuel cell compartment 30 to the deck 1a and is exposed from the upper surface of the deck 1a.

[0043] A battery compartment air supply device 36 and a battery compartment external gas detector 37 are disposed at the end of the battery compartment air supply pipe 35 on the deck 1a side. The battery compartment air supply device 36 and the battery compartment external gas detector 37 are located at the top of the deck 1a.

[0044] The battery compartment air supply device 36 is configured, for example, as an inexpensive non-explosion-proof air supply fan, but may also be configured as an explosion-proof air supply fan. The operation of the battery compartment air supply device 36 is controlled by the control unit 12a. The battery compartment air supply device 36 may be provided with one or more filters (not shown). The filters remove, for example, dust or sea salt particles.

[0045] The battery compartment air supply device 36 supplies air from outside the fuel cell compartment 30 to the inside of the fuel cell compartment 30 via the battery compartment air supply pipe 35 and the battery compartment air supply port 30e. The air inside the fuel cell compartment 30 is discharged to the duct compartment 90 via the battery compartment exhaust port 30f. This ventilates the inside of the fuel cell compartment 30. As a result, it is possible to prevent flammable gas (e.g., fuel gas leaking from the fuel cell 31) from accumulating inside the fuel cell compartment 30.

[0046] The battery compartment external gas detector 37 detects combustible gases (such as hydrogen gas floating around the hull 1) flowing from the outside of the fuel cell compartment 30 into the interior thereof. The battery compartment external gas detector 37 is a combustible gas sensor, such as a hydrogen gas sensor. The battery compartment external gas detector 37 is disposed on the opposite side of the battery compartment air supply device 36 from the battery compartment air supply pipe 35, that is, upstream of the air flow from the outside of the fuel cell compartment 30 to the interior thereof. The battery compartment external gas detector 37 may also be configured as a gas sensor that detects combustible gases other than hydrogen gas. Combustible gases other than hydrogen gas include, for example, methane, ethane, propane, and carbon monoxide.

[0047] The battery compartment external gas detector 37 outputs a detection signal indicating, for example, the concentration of combustible gas to the control unit 12a. Based on the detection signal, the control unit 12a can determine whether the concentration of combustible gas is equal to or greater than a specified value. If the concentration is equal to or greater than the specified value, the control unit 12a controls the fuel cell-side shutoff valve 33 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. The specified value may be determined based on experiments and / or experience.

[0048] The fuel cell ship SH further includes a cooling medium tank 38 and cooling medium piping 39. The cooling medium tank 38 stores a cooling medium for cooling the fuel cells 31. The cooling medium is, for example, an antifreeze liquid with low electrical conductivity. The antifreeze liquid is, for example, a liquid mixture of pure water and ethylene glycol in a predetermined ratio. The cooling medium tank 38 is sealed, but the top may be open.

[0049] The cooling medium piping 39 is a piping for circulating the cooling medium between the fuel cell 31 and a heat exchanger (not shown). A circulation pump (not shown) is also provided midway through the cooling medium piping 39. The circulation pump is driven to supply the cooling medium from the heat exchanger to the fuel cell 31 via the cooling medium piping 39, thereby cooling the fuel cell 31. The cooling medium used to cool the fuel cell 31 is also supplied to the cooling medium tank 38 via the cooling medium piping 39, where volume changes due to temperature changes of the cooling medium are absorbed and the liquid volume of the cooling medium is monitored.

[0050] A cooling tank internal gas detector 38a is provided at an upper portion inside the cooling medium tank 38. The cooling tank internal gas detector 38a is a fuel gas detector that detects fuel gas present in the cooling medium tank 38. The fuel gas present in the cooling medium tank 38 may be, for example, fuel gas that has leaked from the fuel cell 31 and entered the cooling medium tank 38 via the cooling medium piping 39. The detection result of the fuel gas by the cooling tank internal gas detector 38a (for example, information on the concentration of the fuel gas) is sent to the control unit 12a. Based on the detection result by the cooling tank internal gas detector 38a, the control unit 12a can thereby determine whether or not there is a fuel gas leak in the fuel cell 31, and if there is a leak, can perform control to, for example, stop power generation in the fuel cell 31.

[0051] (2-2. Configuration of fuel gas storage section) The fuel gas storage section 4 of the fuel cell ship SH has a fuel tank 41, a gas filling pipe 42, and a tank-side shutoff valve 43. The tank-side shutoff valve 43 is an example of a peripheral device 11.

[0052] The fuel tank 41 stores fuel gas to be supplied to the fuel cell 31. For convenience, only one fuel tank 41 is shown in Fig. 2, but the number of fuel tanks 41 is not particularly limited, and there may be more than one.

[0053] The gas filling pipe 42 is a pipe for refilling the fuel tank 41 with fuel gas or filling it with inert gas. One end of the gas filling pipe 42 is connected to the fuel tank 41. The other end of the gas filling pipe 42 branches into two, which are connected to a fuel gas filling port 82 and an inert gas filling port 84, respectively. The fuel gas filling port 82 and the inert gas filling port 84 are provided in a duct section 90 (particularly the upper duct section 80), which will be described later.

[0054] The inert gas is, for example, nitrogen gas. For example, if fuel gas remains in the fuel tank 41 when the fuel cell ship SH is undergoing maintenance such as inspection or repair in a dock, there is a risk of an explosion if the fuel gas ignites for some reason. Therefore, when performing maintenance on the fuel cell ship SH, the fuel tank 41 is filled with inert gas and the fuel gas is removed from the fuel tank 41. This makes it possible to avoid the risk of explosion.

[0055] In the fuel gas supply pipe 32 described above, the side opposite to the side connected to the fuel cell 31 is connected to the fuel tank 41. In other words, the fuel tank 41 and the fuel cell 31 are connected via the fuel gas supply pipe 32.

[0056] The tank-side shutoff valve 43 is an example of a shutoff valve SV that opens or closes the flow path of the fuel gas supply pipe 32. The opening and closing of the tank-side shutoff valve 43 is controlled by the control unit 12a. Specifically, the tank-side shutoff valve 43 switches between supplying and stopping the supply of fuel gas from the fuel tank 41 to the fuel cell 31 based on the control of the control unit 12a. Only one tank-side shutoff valve 43 is provided on the fuel gas supply pipe 32 in the tank compartment 40, which will be described later, but two or more tank-side shutoff valves 43 may be provided.

[0057] In other words, it can be said that the fuel gas supply pipe 32 connecting the fuel tank 41 and the fuel cell 31 has at least two shutoff valves SV. The at least two shutoff valves SV include the fuel cell-side shutoff valve 33 and the tank-side shutoff valve 43.

[0058] The fuel cell ship SH further includes a tank compartment 40. The tank compartment 40 is a container that houses a fuel tank 41. In other words, the fuel cell ship SH includes the tank compartment 40 in which the fuel tank 41 that stores fuel gas is installed. The tank compartment 40 is disposed in the fuel chamber 14.

[0059] The tank compartment 40 has a hollow shape. For example, the tank compartment 40 has a hollow, approximately rectangular parallelepiped shape. In this case, the outer walls constituting the tank compartment 40 include, for example, a top wall 40a, a bottom wall 40b, a front wall (not shown), a back wall (not shown), a side wall 40c, and a side wall 40d. However, the top, bottom, front, back, and side surfaces of the tank compartment 40 can be arbitrarily determined. Furthermore, the shape of the tank compartment 40 is not particularly limited as long as it has a space large enough to accommodate at least one fuel tank 41. The tank compartment 40 can also be considered as a container, chamber, or box that accommodates the fuel tank 41. The material of the outer walls of the tank compartment 40 is, for example, FRP, but may also be steel plate.

[0060] A tank compartment air supply port 40e is provided in an opening in the side wall 40c of the tank compartment 40. The tank compartment air supply port 40e is connected to a tank compartment air supply pipe 45, which will be described later. Note that the tank compartment air supply port 40e may be provided in an outer wall of the tank compartment 40 other than the side wall 40c.

[0061] Meanwhile, a tank compartment exhaust port 40f is provided in the top wall 40a of the tank compartment 40. The tank compartment exhaust port 40f is connected to a vent pipe 10. The vent pipe 10 is a pipe for directing air inside the tank compartment 40 to the outside of the ship. Note that the tank compartment exhaust port 40f may be provided in an outer wall of the tank compartment 40 other than the top wall 40a.

[0062] The tank compartment 40 has an internal space that is sealed except for the tank compartment air inlet 40e and the tank compartment air outlet 40f.

[0063] The tank compartment 40 accommodates a portion of the fuel gas supply pipe 32 and a tank-side shutoff valve 43. The tank compartment 40 also accommodates an internal tank compartment gas detector 44a and an internal tank compartment fire detector 44b.

[0064] The tank compartment internal gas detector 44a is a fuel gas detector disposed inside the tank compartment 40. For example, when the fuel gas is hydrogen gas, the tank compartment internal gas detector 44a is configured with a hydrogen gas detection sensor.

[0065] The tank compartment internal gas detector 44a is disposed on the top wall 40a located at the top of the tank compartment 40, near the tank compartment vent port 40f or inside the tank compartment vent port 40f. In the unlikely event that fuel gas leaks from the fuel tank 41 inside the tank compartment 40, the leaked fuel gas passes through the tank compartment vent port 40f and heads toward the vent pipe 10. In other words, the tank compartment vent port 40f is located at the most downstream side of the flow path through which the fuel gas flows when the fuel gas leaks inside the tank compartment 40. Therefore, by disposing the tank compartment internal gas detector 44a at a position near the tank compartment vent port 40f or inside the tank compartment vent port 40f, no matter where the fuel gas leaks inside the tank compartment 40, the leaked fuel gas can be reliably detected by the tank compartment internal gas detector 44a located at the most downstream side of the flow path.

[0066] When the tank compartment internal gas detector 44a detects fuel gas in the tank compartment 40, the detection signal is sent from the tank compartment internal gas detector 44a to the control unit 12a. This enables the control unit 12a to control the tank-side shutoff valve 43 provided in the fuel gas supply pipe 32 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. Details of the opening and closing control of the tank-side shutoff valve 43 will be described later.

[0067] The tank compartment internal fire detector 44b is a fire detector disposed inside the tank compartment 40. The tank compartment internal fire detector 44b includes, for example, one or more sensors selected from a smoke sensor that detects smoke, a heat sensor that detects heat, and a flame sensor that detects flame. The tank compartment internal fire detector 44b may be configured as a thermocouple-type fire detector.

[0068] The tank compartment internal fire detector 44b is disposed on the inner surface of the top wall 40a located at the top of the tank compartment 40. In the unlikely event that a fire breaks out inside the tank compartment 40, the tank compartment internal fire detector 44b detects the fire and outputs a detection signal indicating the occurrence of a fire to the control unit 12a. In this case, the control unit 12a controls the tank-side shutoff valve 43 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. This makes it possible to minimize the risk of an explosion in the tank compartment 40 due to ignition of the fuel gas.

[0069] A tank compartment air supply pipe 45 is connected to the tank compartment 40. The tank compartment air supply pipe 45 extends from the tank compartment air supply port 40e of the tank compartment 40 to the deck 1a and is exposed from the upper surface of the deck 1a.

[0070] A tank compartment air supply device 46 and a tank compartment external gas detector 47 are disposed at the end of the tank compartment air supply pipe 45 on the deck 1a side. The tank compartment air supply device 46 and the tank compartment external gas detector 47 are located at the top of deck 1a.

[0071] The tank compartment air supply device 46 is configured, for example, by an inexpensive non-explosion-proof air supply fan, but may also be configured by an explosion-proof air supply fan. The operation of the tank compartment air supply device 46 is controlled by the control unit 12a. One or more filters (not shown) may be arranged in the tank compartment air supply device 46. The filters remove, for example, dust or sea salt particles.

[0072] The tank compartment air supply device 46 supplies air from outside the tank compartment 40 to the inside of the tank compartment 40 via the tank compartment air supply pipe 45 and the tank compartment air supply port 40e. The air inside the tank compartment 40 is discharged to the vent pipe 10 via the tank compartment exhaust port 40f. This ventilates the inside of the tank compartment 40. As a result, even if fuel gas leaks from the fuel tank 41 inside the tank compartment 40, the accumulation of the fuel gas can be suppressed.

[0073] The tank compartment external gas detector 47 detects flammable gases (such as hydrogen gas floating around the hull 1) flowing from the outside of the tank compartment 40 into the inside. The tank compartment external gas detector 47 is a flammable gas sensor such as a hydrogen gas sensor. The tank compartment external gas detector 47 is disposed on the opposite side of the tank compartment air supply device 46 from the tank compartment air supply pipe 45, that is, upstream of the air flow from the outside of the tank compartment 40 to the inside. The tank compartment external gas detector 47 may be configured as a gas sensor that detects flammable gases other than hydrogen gas.

[0074] The tank compartment external gas detector 47 outputs a detection signal indicating, for example, the concentration of combustible gas to the control unit 12a. Based on the detection signal, the control unit 12a can determine whether the concentration of combustible gas is equal to or greater than a specified value. If the concentration is equal to or greater than the specified value, the control unit 12a controls the tank-side shutoff valve 43 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. The specified value may be determined based on experiments and / or experience.

[0075] (2-3. Duct Section) The fuel cell ship SH further includes a lower duct section 70 and an upper duct section 80. Here, the lower duct section 70 and the upper duct section 80 are collectively referred to as a duct section 90. The duct section 90 is a housing that houses various types of piping. For example, the duct section 90 houses a portion of the fuel gas supply piping 32. In other words, the fuel cell ship SH further includes a duct section 90 that houses a portion of the fuel gas supply piping 32. The interior of the lower duct section 70 and the interior of the upper duct section 80 are connected via a duct connection section 91. The lower duct section 70 and the upper duct section 80 will be described in detail below.

[0076] 2-3-1. Lower duct section The lower duct section 70 is disposed below the deck 1a. Specifically, the lower duct section 70 is disposed in the engine room 13. Within the engine room 13, the lower duct section 70 is located aft of the fuel cell section 30. In other words, the lower duct section 70 is located below the deck 1a, between the fuel cell section 30 and the tank section 40. The lower duct section 70 accommodates a portion of the fuel gas supply piping 32 and a portion of the gas fill piping 42.

[0077] Here, the "part of the fuel gas supply piping 32" accommodated in the lower duct section 70 refers to the part of the fuel gas supply piping 32 that is located between the fuel cell section 30 and the tank section 40. In addition, the "part of the gas fill piping 42" accommodated in the lower duct section 70 refers to the part of the gas fill piping 42 that is located between the tank section 40 and the upper duct section 80.

[0078] The lower duct section 70 is made of a material such as FRP, but may also be made of steel plate. The lower duct section 70 has a hollow shape. For example, the lower duct section 70 has a hollow, approximately rectangular parallelepiped shape. In this case, the outer walls constituting the lower duct section 70 include, for example, a top wall 70a, a bottom wall 70b, a front wall (not shown), a back wall (not shown), a side wall 70c, and a side wall 70d. However, the top, bottom, front, back, and side surfaces of the lower duct section 70 can be arbitrarily determined. Furthermore, the shape of the lower duct section 70 is not particularly limited as long as it has a space large enough to accommodate a portion of the fuel gas supply pipe 32, etc. The lower duct section 70 can also be considered as a container, chamber, or box that accommodates a portion of the fuel gas supply pipe 32, etc.

[0079] A lower duct section air intake port 70e is provided in a side wall 70d of the lower duct section 70. The lower duct section air intake port 70e is connected to a lower duct section air intake pipe 74, which will be described later. Note that the lower duct section air intake port 70e may be provided in an outer wall of the lower duct section 70 other than the side wall 70d.

[0080] Meanwhile, a lower duct section communication port 70f is provided in the top wall 70a of the lower duct section 70. The lower duct section communication port 70f is in communication with the above-mentioned duct communication portion 91. Note that the lower duct section communication port 70f may be provided in an outer wall of the lower duct section 70 other than the top wall 70a.

[0081] Furthermore, a battery compartment communication port 70g is provided in the side wall 70d of the lower duct section 70. The battery compartment communication port 70g is connected to the battery compartment exhaust port 30f of the fuel cell section 30 described above via a communication pipe 92. As a result, air inside the fuel cell section 30 flows into the lower duct section 70 via the battery compartment exhaust port 30f, the communication pipe 92, and the battery compartment communication port 70g. Note that the battery compartment communication port 70g may be provided in an outer wall of the lower duct section 70 other than the side wall 70d.

[0082] The communicating pipe 92 is configured, for example, as a double pipe consisting of an inner pipe and an outer pipe. The inner pipe is configured, for example, as the fuel gas supply pipe 32. The outer pipe is located radially outside the inner pipe. Gas inside the fuel cell compartment 30 flows from the cell compartment exhaust port 30f, passing between the inner pipe and the outer pipe of the communicating pipe 92, toward the cell compartment communicating port 70g of the lower duct compartment 70.

[0083] The lower duct section 70 has an internal space that is sealed except for the lower duct section air intake port 70e, the lower duct section communication port 70f, and the battery section communication port 70g.

[0084] The lower duct section 70 accommodates a portion of the fuel gas discharge pipe 71. The fuel gas discharge pipe 71 is a fuel discharge pipe that branches off from the fuel gas supply pipe 32 located inside the lower duct section 70. For example, the fuel gas discharge pipe 71 is located between two shutoff valves SV and branches off from the fuel gas supply pipe 32.

[0085] More specifically, the fuel gas discharge pipe 71 branches off from the fuel gas supply pipe 32 between the tank-side shutoff valve 43 in the tank compartment 40 and the fuel cell-side shutoff valve 33 in the fuel cell compartment 30. The fuel gas discharge pipe 71 extends from the inside of the lower duct compartment 70 to the inside of the upper duct compartment 80 via the lower duct compartment communication port 70f and the duct communication section 91, and further communicates with the inside of the vent pipe 10. Therefore, the "part of the fuel gas discharge pipe 71" accommodated in the lower duct compartment 70 refers to the portion of the fuel gas discharge pipe 71 located between the branch point with the fuel gas supply pipe 32 and the upper duct compartment 80.

[0086] The lower duct section 70 further accommodates a release valve 72. The release valve 72 is an on-off valve that is installed in the fuel gas discharge pipe 71 and opens or closes the flow path of the fuel gas discharge pipe 71. The release valve 72 is an example of a peripheral device 11. The opening and closing of the release valve 72 is controlled by the control unit 11.

[0087] In this way, when the shutoff valve SV installed in the tank compartment 40 is the tank-side shutoff valve 43 and the shutoff valve SV installed in the fuel cell compartment 30 is the fuel cell-side shutoff valve 33, the fuel cell ship SH further includes a fuel gas discharge pipe 71 branching off from the fuel gas supply pipe 32 between the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33, and a release valve 72 installed in the fuel gas discharge pipe 71. The release valve 72 may also be installed in the upper duct compartment 80.

[0088] The lower duct section 70 further houses a lower duct section internal gas detector 73. The lower duct section internal gas detector 73 is a fuel gas detector disposed inside the lower duct section 70. For example, when the fuel gas is hydrogen gas, the lower duct section internal gas detector 73 is configured with a hydrogen gas detection sensor.

[0089] The lower duct section internal gas detector 73 is disposed on the top wall 70a located above the lower duct section 70, near the lower duct section communication port 70f or inside the lower duct section communication port 70f. In the unlikely event that fuel gas leaks from the fuel gas supply pipe 32 inside the lower duct section 70, the leaked fuel gas passes through the lower duct section communication port 70f and heads toward the upper duct section 80. In other words, the lower duct section communication port 70f is located at the most downstream side of the flow path through which the fuel gas flows when fuel gas leaks inside the lower duct section 70. Therefore, by disposing the lower duct section internal gas detector 73 near the lower duct section communication port 70f or inside the lower duct section communication port 70f, regardless of the location of the fuel gas leak within the lower duct section 70, the leaked fuel gas can be reliably detected by the lower duct section internal gas detector 73 located at the most downstream side of the flow path.

[0090] When the lower duct section internal gas detector 73 detects fuel gas in the lower duct 70, the detection signal is sent from the lower duct section internal gas detector 73 to the control unit 12a. As a result, the control unit 12a controls the shutoff valve SV provided in the fuel gas supply pipe 32 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31.

[0091] It should be noted that the lower duct section 70 may further house a fire detector for detecting a fire inside the lower duct section 70 .

[0092] A lower duct section air intake pipe 74 is connected to the lower duct section 70. The lower duct section air intake pipe 74 extends from a lower duct section air intake port 70e of the lower duct section 70 to the deck 1a and is exposed from the upper surface of the deck 1a.

[0093] A lower duct section air supply device 75 and a lower duct section external gas detector 76 are disposed at the end of the lower duct section air supply pipe 74 on the deck 1a side. The lower duct section air supply device 75 and the lower duct section external gas detector 76 are located at the upper part of deck 1a.

[0094] The lower duct section air intake device 75 is configured, for example, by an inexpensive non-explosion-proof air intake fan, but may also be configured by an explosion-proof air intake fan. The driving of the lower duct section air intake device 75 is controlled by the control unit 12a. The lower duct section air intake device 75 may be provided with one or more filters (not shown). The filters remove, for example, dust or sea salt particles.

[0095] The lower duct section air supply device 75 supplies air from outside the lower duct section 70 (duct section 90) to the interior of the lower duct section 70 via the lower duct section air supply pipe 74 and the lower duct section air supply port 70e. The air inside the lower duct section 70 is discharged to the upper duct section 80 via the lower duct section communication port 70f. This ventilates the interior of the lower duct section 70. As a result, even if fuel gas leaks from the fuel gas supply pipe 32 inside the lower duct section 70, the accumulation of the fuel gas can be suppressed.

[0096] The lower duct section external gas detector 76 detects combustible gases (such as hydrogen gas floating around the hull 1) flowing from the outside of the duct section 90 into the inside. The lower duct section external gas detector 76 is a combustible gas sensor such as a hydrogen gas sensor. The lower duct section external gas detector 76 is disposed on the opposite side of the lower duct section air supply device 75 from the lower duct section air supply pipe 74, that is, on the upstream side of the air flow from the outside of the duct section 90 to the inside. The lower duct section external gas detector 76 may be configured as a gas sensor that detects combustible gases other than hydrogen gas.

[0097] The lower duct section external gas detector 76 outputs a detection signal indicating, for example, the concentration of combustible gas to the control unit 12a. Based on the detection signal, the control unit 12a can determine whether the concentration of combustible gas is equal to or greater than a specified value. If the concentration is equal to or greater than the specified value, the control unit 12a controls the shutoff valve SV to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31. The specified value may be determined based on experiments and / or experience.

[0098] 2-3-2. Upper duct section The upper duct section 80 is disposed on the upper part of the deck 1a. Specifically, the upper duct section 80 is disposed on the deck 1a, spanning from the lower duct section 70 to the tank section 40. The upper duct section 80 accommodates a portion of the fuel gas discharge piping 71 and a portion of the gas fill piping 42.

[0099] Here, the "part of the fuel gas discharge piping 71" accommodated in the upper duct section 80 refers to the portion of the fuel gas discharge piping 71 that exits the lower duct section 70 and extends toward the vent pipe 10. Additionally, the "part of the gas fill piping 42" accommodated in the upper duct section 80 refers to the portion of the gas fill piping 42 that exits the lower duct section 70 and extends to the fuel gas fill port 82, which will be described later.

[0100] The upper duct section 80 is made of a material such as FRP, but may also be made of steel plate. The upper duct section 80 has a hollow shape. For example, the upper duct section 80 has a hollow, approximately rectangular parallelepiped shape. In this case, the outer walls constituting the upper duct section 80 include, for example, a top wall 80a, a bottom wall 80b, a front wall (not shown), a back wall (not shown), a side wall 80c, and a side wall 80d. However, the top, bottom, front, back, and side surfaces of the upper duct section 80 can be determined arbitrarily. Furthermore, the shape of the upper duct section 80 is not particularly limited as long as it has a space large enough to accommodate a portion of the fuel gas discharge pipe 71, etc. The upper duct section 80 can also be considered as a container, chamber, or box that accommodates a portion of the fuel gas discharge pipe 71, etc.

[0101] As described above, the fuel gas discharge pipe 71 communicates with the inside of the vent pipe 10. As a result, when the release valve 72 is opened, gas (e.g., fuel gas) inside the fuel gas discharge pipe 71 flows from the end 71a of the fuel gas discharge pipe 71 into the inside of the vent pipe 10 and is discharged from the vent pipe 10 to the outside of the ship. Here, it is desirable that the end 71a of the fuel gas discharge pipe 71 be positioned upward inside the vent pipe 10, that is, facing the open port side of the vent pipe 10. In this case, the discharge direction of the gas released from the end 71a of the fuel gas discharge pipe 71 is upward.

[0102] For example, if fuel gas is discharged sideways from the end 71a of the fuel gas discharge pipe 71, the discharged fuel gas may hit the inner wall surface of the vent pipe 10 and flow downward, which may result in malfunction of the tank compartment internal gas detector 44a in the tank compartment 40. By positioning the end 71a of the fuel gas discharge pipe 71 facing upward inside the vent pipe 10 as described above, it is possible to reduce the risk of malfunction of the tank compartment internal gas detector 44a due to fuel gas discharged from the end 71a.

[0103] An upper duct section air inlet 80e is provided in the bottom wall 80b of the upper duct section 80. The upper duct section air inlet 80e is connected to the duct connection portion 91. Therefore, the upper duct section 80 is connected to the lower duct section 70 via the upper duct section air inlet 80e, the duct connection portion 91, and the lower duct connection port 70f. Note that the upper duct section air inlet 80e may be provided in an outer wall of the upper duct section 80 other than the bottom wall 80b.

[0104] The upper duct section 80 has a vent pipe communication part 81. The vent pipe communication part 81 is a pipe that communicates the interior of the upper duct section 80 with the vent pipe 10. In FIG. 2, the vent pipe communication part 81 is illustrated as having a shape that is bent upward from the horizontal direction, but the shape of the vent pipe communication part 81 is not limited to the shape shown in FIG. 2. The reason that the vent pipe communication part 81 is bent upward is the same as the reason that the end part 71a of the fuel gas discharge pipe 71 is bent upward, and is to reduce the risk of the tank compartment internal gas detector 44a malfunctioning due to the fuel gas, which will be described later, being discharged from the vent pipe communication part 81.

[0105] The vent pipe 10 extends upward from the tank section 40 and is positioned inside the upper duct section 80. More specifically, the vent pipe 10 penetrates the bottom wall 80b of the upper duct section 80 to enter the interior of the vent pipe 10 and is positioned by penetrating through the top wall 80a. The vent pipe communication section 81 is provided inside the upper duct section 80, penetrating the side wall of the vent pipe 10. As a result, the upper duct section 80 is connected to the vent pipe 10 via the vent pipe communication section 81.

[0106] Therefore, the air inside the upper duct section 80 is discharged outside the ship via the vent pipe communication part 81 and the vent pipe 10. This allows ventilation inside the upper duct section 80. Furthermore, even if fuel gas leaks from the fuel gas discharge pipe 71 inside the upper duct section 80, the leaked fuel gas is discharged outside the ship via the vent pipe communication part 81 and the vent pipe 10. This prevents the leaked fuel gas from accumulating inside the upper duct section 80.

[0107] Furthermore, the upper duct section 80 and the lower duct section 70 are connected via a duct communication section 91. This allows (1) air taken into the lower duct 70 via the lower duct section air supply pipe 74, (2) fuel gas that has leaked for some reason from the fuel gas supply pipe 32 in the lower duct 70, and (3) air or fuel gas discharged from the fuel cell section 30 to the lower duct section 70 via the communication pipe 92 to be released outside the ship via the upper duct section 80 and the vent pipe 10. This makes it possible to prevent fuel gas from accumulating inside the lower duct section 70 and the fuel cell section 30.

[0108] The upper duct section 80 is provided with a fuel gas filling port 82 and a fuel gas check valve 83. The fuel gas filling port 82 is connected to the gas filling piping 42. The fuel gas check valve 83 is provided in the gas filling piping 42. More specifically, the fuel gas check valve 83 is located between the fuel gas filling port 82 and the branch point between the gas filling piping 42 and an inert gas piping 87 (described below).

[0109] When fuel gas is supplied from the fuel gas fill port 82, the fuel gas passes through the gas fill pipe 42 via the fuel gas check valve 83 and is supplied to the fuel tank 41 in the tank compartment 40. In this way, the fuel tank 41 is filled with fuel gas and stored therein. The fuel gas check valve 83 is provided to prevent backflow of fuel gas from the fuel tank 41 to the fuel gas fill port 82.

[0110] The upper duct section 80 is further provided with an inert gas filling port 84, an on-off valve 85, an inert gas check valve 86, and an inert gas pipe 87. The inert gas filling port 84 is connected to the inert gas pipe 87. The inert gas pipe 87 is provided within the upper duct section 80 and branches off from the gas filling pipe 42. The on-off valve 85 and the inert gas check valve 86 are provided in the inert gas pipe 87. In the inert gas pipe 87, the on-off valve 85 is located between the inert gas filling port 84 and the inert gas check valve 86.

[0111] The on-off valve 85 opens or closes the flow path of the inert gas pipe 87. In a configuration in which the inert gas check valve 86 is provided in the inert gas pipe 87, the on-off valve 85 may be omitted.

[0112] When inert gas is supplied to the inert gas fill port 84 while fuel gas is not being supplied to the fuel gas fill port 82, and the on-off valve 85 opens the flow path of the inert gas piping 87, the inert gas passes through the inert gas check valve 86 and is supplied to the fuel tank 41 in the tank compartment 40 via the inert gas piping 87 and the gas fill piping 42. Furthermore, the tank-side shutoff valve 43 opens the flow path of the fuel gas supply piping 32, the fuel cell-side shutoff valve 33 closes the flow path of the fuel gas supply piping 32, and the release valve 72 opens the flow path of the fuel gas discharge piping 71, so that the fuel gas remaining in the fuel tank 41 is discharged to the vent pipe 10 via the fuel gas supply piping 32 and the fuel gas discharge piping 71. This allows the fuel gas to be removed from the fuel tank 41 (purging process).

[0113] It should be noted that there may be a pipe that connects the gas filling pipe 42 directly to the fuel gas supply pipe 32 between the fuel tank 41 and the tank-side shutoff valve 43 (tank system). In this configuration, when purging the fuel tank 41 of inert gas, the fuel tank 41 is filled with inert gas while the tank-side shutoff valve 43 is closed, and then the tank-side shutoff valve 43 must be opened in order to facilitate the release of the inert gas from the fuel tank 41.

[0114] As described above, the fuel gas filling port 82 and the inert gas filling port 84 are provided in the upper duct section 80. More specifically, the fuel gas filling port 82 and the inert gas filling port 84 are located at the boundary surface between the inside and outside of the upper duct section 80. In other words, "the fuel gas filling port 82 and the inert gas filling port 84 are provided in the upper duct section 80" includes the case where the fuel gas filling port 82 and the inert gas filling port 84 are provided at the above-mentioned boundary surface of the upper duct section 80.

[0115] Also housed within the upper duct section 80 is an upper duct section internal gas detector 88. The upper duct section internal gas detector 88 is a fuel gas detector disposed within the upper duct section 80. For example, if the fuel gas is hydrogen gas, the upper duct section internal gas detector 88 is configured as a hydrogen gas detection sensor.

[0116] The upper duct section internal gas detector 88 is disposed on the top wall 80a located at the top of the upper duct section 80. Hydrogen gas, which serves as fuel gas, is lighter than air and rises. Therefore, even if fuel gas leaks inside the upper duct section 80, the leaked fuel gas can be reliably detected by the upper duct section internal gas detector 88. Note that, in order to more reliably detect fuel gas leaking inside the upper duct section 80, the upper duct section internal gas detector 88 may be disposed in a position close to the vent pipe communication portion 81.

[0117] When the upper duct section internal gas detector 88 detects fuel gas in the upper duct section 80, the detection signal is sent from the upper duct section internal gas detector 88 to the control unit 12a. As a result, the control unit 12a controls the shutoff valve SV provided in the fuel gas supply pipe 32 to stop the supply of fuel gas from the fuel tank 41 to the fuel cell 31.

[0118] Additionally, the upper duct section 80 may further house a fire detector for detecting a fire inside the upper duct section 80 .

[0119] (2-4. Supplementary information about vent pipes) A vent pipe internal gas detector 10a is provided inside the vent pipe 10, downstream of the outlet 81a of the vent pipe communication section 81. Note that the "downstream side" mentioned above refers to the downstream side of the air flow direction when the air inside the tank compartment 40 flows through the inside of the vent pipe 10 and is discharged overboard. For example, if the fuel gas is hydrogen gas, the vent pipe internal gas detector 10a is composed of a diffusion-type or suction-type hydrogen gas detection sensor. A detection signal from the vent pipe internal gas detector 10a is sent to the control section 12a. Note that the control of the control section 12a based on the detection result of the vent pipe internal gas detector 10a will be described later.

[0120] [3. Controlling the opening and closing of shutoff valves] As described above, in the fuel gas supply pipe 32, at least one tank-side shutoff valve 43 is provided in the tank compartment 40, and at least one fuel cell-side shutoff valve 33 is provided in the fuel cell compartment 30. In other words, at least one shutoff valve SV (tank-side shutoff valve 43, fuel cell-side shutoff valve 33) is installed in each of the tank compartment 40 and the fuel cell compartment 30.

[0121] Furthermore, a tank compartment internal gas detector 44a is installed in the tank compartment 40, and a battery compartment internal gas detector 34a is installed in the fuel cell compartment 30. In other words, a fuel gas detector (tank compartment internal gas detector 44a, battery compartment internal gas detector 34a) that detects fuel gas, which is a gaseous state of fuel, is installed in each of the tank compartment 40 and the fuel cell compartment 30.

[0122] In this configuration, the control unit 12a controls the opening and closing of the shutoff valve SV based on the detection signal (detection result) output from the fuel gas detector as follows. A specific example of the opening and closing control of the shutoff valve SV will be described below based on the flowcharts in Figure 3 and subsequent figures, with appropriate reference to Figures 1 and 2. Unless otherwise specified, it is assumed that the control unit 12a issues a close command (a control signal to close) to the release valve 72, causing the release valve 72 to be closed.

[0123] (3-1. Specific example 1 of shutoff valve opening / closing control) 3 is a flowchart showing a process flow according to an example of the open / close control of the shutoff valve SV in this embodiment. When the tank compartment internal gas detector 44a detects that the concentration of fuel gas in the tank compartment 40 is equal to or higher than the standard value (Yes in S1), the control unit 12a outputs a close signal to both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33, closing both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 (S2). This stops the supply of fuel gas from the fuel tank 41 to the fuel cell 31 via the fuel gas supply pipe 32.

[0124] The above-mentioned standard value can be, for example, 40% LEL, but as mentioned above, it may be determined appropriately based on experiments or experience (the same applies to the standard values ​​that appear below).

[0125] Even if the tank compartment internal gas detector 44a detects in S1 that the fuel gas concentration in the tank compartment 40 is below the standard value (No in S1), if the battery compartment internal gas detector 34a detects that the fuel gas concentration in the fuel cell compartment 30 is equal to or greater than the standard value (Yes in S3), the control unit 12a outputs a close signal to both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33, closing both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 (S2). Therefore, in this case as well, the supply of fuel gas from the fuel tank 41 to the fuel cell 31 via the fuel gas supply pipe 32 is stopped.

[0126] On the other hand, in S3, if the cell compartment internal gas detector 34a detects that the concentration of fuel gas in the fuel cell compartment 30 is below the standard value (No in S13), the control unit 12a outputs an open signal to both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33, causing both the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 to open (S4). In this case, fuel gas is supplied from the fuel tank 41 to the fuel cell 31 via the fuel gas supply pipe 32. Note that the order of S1 and S3 may be reversed.

[0127] (3-2. Specific example 2 of shutoff valve opening / closing control) 4 is a flowchart showing the process flow of another example of the opening and closing control of the shutoff valve SV. The control unit 12a may control the opening and closing of the shutoff valve SV as follows. That is, when the tank compartment internal gas detector 44a detects that the concentration of fuel gas in the tank compartment 40 is equal to or higher than the standard value (Yes in S11), the control unit 12a outputs a closure signal to the tank-side shutoff valve 43, causing the tank-side shutoff valve 43 to close (S12). Closing the tank-side shutoff valve 43 stops the supply of fuel gas from the fuel tank 41 to the fuel cell 31.

[0128] In S11, when the tank compartment internal gas detector 44a detects that the concentration of fuel gas in the tank compartment 40 is below the standard value (No in S11), the control unit 12a outputs an open signal to the tank side shut-off valve 43, causing the tank side shut-off valve 43 to open (S13).

[0129] Furthermore, if the cell compartment internal gas detector 34a detects that the concentration of fuel gas in the fuel cell compartment 30 is equal to or higher than the standard value (Yes in S14), the control unit 12a outputs a closure signal to the fuel cell-side shutoff valve 33 to close the fuel cell-side shutoff valve 33 (S15). As a result, even if the tank-side shutoff valve 43 is open, the supply of fuel gas from the fuel tank 41 to the fuel cell 31 is stopped due to the closure of the fuel cell-side shutoff valve 33.

[0130] If the cell compartment internal gas detector 34a detects in S14 that the concentration of fuel gas in the fuel cell compartment 30 is below the standard value (No in S14), the control unit 12a outputs an open signal to the fuel cell-side shutoff valve 33 to open the fuel cell-side shutoff valve 33 (S16). Therefore, if the tank-side shutoff valve 43 is open in S13, the opening of the fuel cell-side shutoff valve 33 in S16 causes fuel gas to be supplied from the fuel tank 41 to the fuel cell 31.

[0131] Thus, in specific examples 1 and 2, when the concentration of fuel gas in both the tank compartment 40 and the fuel cell compartment 30 is below the standard value, fuel gas is supplied from the fuel tank 41 to the fuel cell 31 via the fuel gas supply pipe 32. Furthermore, when the concentration of fuel gas in at least one of the tank compartment 40 and the fuel cell compartment 30 is equal to or greater than the standard value, the supply of fuel gas from the fuel tank 41 to the fuel cell 31 via the fuel gas supply pipe 32 is stopped.

[0132] Furthermore, the following can be said from specific examples 1 and 2. That is, when the tank compartment internal gas detector 44a detects that the fuel gas concentration is equal to or greater than the standard value, the control unit 12a closes the shutoff valve SV (tank-side shutoff valve 43) in the compartment (tank compartment 40) in which the tank compartment internal gas detector 44a is installed. Furthermore, when the battery compartment internal gas detector 34a detects that the fuel gas concentration is equal to or greater than the standard value, the control unit 12a closes the shutoff valve SV (fuel cell-side shutoff valve 33) in the compartment (fuel cell compartment 30) in which the battery compartment internal gas detector 34a is installed (see S2, S12, S15).

[0133] As described above, the fuel cell ship SH of this embodiment is equipped with a control unit 12a that controls the opening and closing of the shutoff valves SV. When at least one of the fuel gas detectors (at least one of the tank compartment internal gas detector 44a and the battery compartment internal gas detector 34a) (installed in the tank compartment 40 and the fuel cell compartment 30) detects that the fuel gas concentration is equal to or higher than a predetermined standard value, the control unit 12a closes the shutoff valve SV in the compartment of the tank compartment 40 or the fuel cell compartment 30 where the fuel gas detector that detected the concentration equal to or higher than the standard value is installed.

[0134] If the shutoff valve SV in the compartment where the fuel gas detector (tank compartment internal gas detector 44a or battery compartment internal gas detector 34a) that detects that the fuel gas concentration is above the standard value is installed is closed and the supply of fuel gas from the fuel tank 41 to the fuel cell 31 is stopped, the fuel cell 31 will no longer be able to generate electricity through an electrochemical reaction with the fuel gas. In other words, if a fuel gas leak occurs in the compartment such that the concentration is above the standard value, the power generation of the fuel cell 31 can be stopped. Note that even if power generation by the fuel cell 31 is stopped, it is possible to continue propelling the fuel cell ship SH by the propulsion device 6 using power supplied from the storage batteries of the storage battery system 5.

[0135] In particular, when at least one of the fuel gas detectors (at least one of the gas detector 44a inside the tank compartment and the gas detector 34a inside the battery compartment) detects that the concentration of the fuel gas is above the standard value, the control unit 12a closes the shut-off valves SV (tank side shut-off valve 43, fuel cell side shut-off valve 33) in all compartments (S2).

[0136] When the concentration of fuel gas reaches or exceeds the specified value, the shutoff valves SV in all compartments, including the tank compartment 40 and the fuel cell compartment 30, are closed. This reliably stops the supply of fuel gas from the fuel tank 41 to the fuel cell 31, and reliably stops power generation by the fuel cell 31.

[0137] [4. Combined use of release valve opening / closing control] Fig. 5 is a flowchart showing the flow of processing when the opening and closing control of the shutoff valve SV in the above-described specific example 1 is performed in addition to the opening and closing control of the release valve 72. The flowchart in Fig. 5 is the same as Fig. 3 except for the addition of the step S2-1. When at least one of the fuel gas detectors (at least one of the tank compartment internal gas detector 44a and the battery compartment internal gas detector 34a) detects that the concentration of the fuel gas is equal to or greater than the standard value (Yes in S1 or Yes in S3), the control unit 12a closes the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 (S2), while desirably opening the release valve 72 (S2-1).

[0138] When the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 are closed in S2, fuel gas remains between the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 in the fuel gas supply pipe 32. If high-pressure fuel gas is left remaining in the fuel gas supply pipe 32, there is a risk of explosion due to ignition if the fuel gas leaks for some reason.

[0139] In S2-1, the control unit 12a opens the release valve 72, whereby the fuel gas remaining in the fuel gas supply pipe 32 between the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 can be released to the outside (for example, overboard) via the release valve 72. This makes it possible to avoid a situation in which high-pressure fuel gas is left remaining in the fuel gas supply pipe 32.

[0140] Fig. 6 is a flowchart showing the process flow according to another example of the opening / closing control of the release valve 72. The flowchart in Fig. 6 is the same as Fig. 5 except for the addition of steps S2-2 and S2-3. After opening the release valve 72 in S2-1, the control unit 12a preferably closes the release valve 72 when the pressure in the fuel gas supply pipe 32 reaches a predetermined pressure (S2-2, S2-3).

[0141] The above-mentioned predetermined pressure refers to, for example, atmospheric pressure. Whether the pressure inside the fuel gas supply pipe 32 has reached the predetermined pressure may be determined by the control unit 12a determining whether a predetermined time (for example, one second) has elapsed since the release valve 72 was opened. Alternatively, the pressure inside the fuel gas supply pipe 32 may be measured with a pressure gauge, and based on the measurement result, the control unit 12a may determine whether the pressure inside the fuel gas supply pipe 32 has reached the predetermined pressure.

[0142] If the release valve 72 is left open and under atmospheric pressure for a long period of time, air will enter the fuel gas supply pipe 32 from the outside (for example, via the vent pipe 10). In this case, when the release valve 72 is closed and the shutoff valve SV is opened to supply fuel gas from the fuel tank 41 to the fuel cell 31 in order to restart the fuel cell ship SH, the air present in the fuel gas supply pipe 32 will also be supplied to the fuel cell 31. This air may cause problems such as oxidizing and corroding the electrodes of the fuel cell 31.

[0143] After the release valve 72 is opened and the pressure in the fuel gas supply pipe 32 reaches a predetermined pressure, the release valve 72 is closed, thereby preventing air from entering the fuel gas supply pipe 32 from the outside (through the vent pipe 10) via the release valve 72. This reduces the risk of problems such as corrosion of the electrodes of the fuel cell 31 caused by the air.

[0144] FIG. 7 is a flowchart showing the flow of processing according to yet another example of the opening / closing control of the release valve 72. The flowchart in FIG. 7 is the same as that in FIG. 6, except that step S2-2 is replaced with step S2-2'. The control unit 12a may close the release valve 72 after a predetermined time has elapsed since opening the release valve 72 in S2-1 (S2-2', S2-3). Note that the predetermined time is desirably set to a time shorter than the time it takes for the pressure in the fuel gas supply pipe 32 to reach atmospheric pressure after the release valve 72 is opened. From this perspective, the predetermined time may be set to several seconds (for example, 1 second).

[0145] As mentioned above, if air (including oxygen) is present in the fuel gas supply pipe 32, when the release valve 72 is closed and the shut-off valve SV is opened to supply fuel gas from the fuel tank 41 to the fuel cell 31 in order to restart the fuel cell ship SH, the air will also be supplied to the fuel cell 31, which may cause problems such as corrosion of the electrodes of the fuel cell 31.

[0146] By closing the release valve 72 after a predetermined time has elapsed since the release valve 72 was opened, it is possible to minimize the amount of air that enters the fuel gas supply pipe 32 from the outside through the release valve 72. This makes it possible to minimize the risk of problems such as corrosion of the electrodes of the fuel cell 31.

[0147] [5. Controlling the opening and closing of shutoff valves and release valves, taking into account duct sections] Fig. 8 is a flowchart showing a process flow according to an example of control of opening and closing the shutoff valve SV and the release valve 72, taking into consideration the detection of fuel gas in the duct section. The flowchart in Fig. 8 is the same as Fig. 5, except that step S3-1 is added between S3 and S4. Note that Fig. 8 does not show the steps (S2-2, S2-2', S2-3) of closing the release valve 72 after opening it, as shown in Figs. 6 and 7, but it goes without saying that these steps may also be performed.

[0148] In this embodiment, as described above, a fuel gas detector is installed in the duct section 90 in addition to the tank section 40 and the fuel cell section 30. For example, an upper duct section internal gas detector 88 is installed in the upper duct section 80. In this configuration, the control unit 12a may close the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 when the fuel gas detector in the duct section 90 (e.g., the upper duct section internal gas detector 88) detects that the fuel gas concentration is equal to or higher than the standard value (S3-1, S2). Note that the control unit 12a may close the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 when the fuel gas detector in the lower duct section 70 (the lower duct section internal gas detector 73) detects that the fuel gas concentration is equal to or higher than the standard value.

[0149] Even if a fuel gas leak occurs in the duct section 90 such that the fuel gas concentration exceeds the specified value, the tank-side shutoff valve 43 and the fuel cell-side shutoff valve 33 are closed. This stops the supply of fuel gas from the fuel tank 41 to the fuel cell 31. Therefore, even if a fuel gas leak occurs in the duct section 90, power generation by the fuel cell 31 can be stopped.

[0150] [6. Discharge valve failure determination] In this embodiment, as described above, the fuel gas discharge pipe 71 branching off from the fuel gas supply pipe 32 extends from inside the lower duct section 70 to inside the upper duct section 80 and further communicates with the inside of the vent pipe 10. In this configuration, the fuel gas discharged from the fuel gas discharge pipe 71 via the release valve 72 is guided to the vent pipe 10 and can be discharged to the outside via the vent pipe 10. In addition, a vent pipe internal gas detector 10a is provided inside the vent pipe 10.

[0151] In this way, when the fuel cell ship SH is configured to include a vent pipe 10 that guides fuel gas discharged from the fuel gas discharge pipe 71 via the discharge valve 72 to the outside, and a vent pipe internal gas detector 10a that detects fuel gas inside the vent pipe 10, the control unit 12a can determine whether or not there is a malfunction in the discharge valve 72 by using the detection results of the vent pipe internal gas detector 10a. This will be explained in detail below.

[0152] 9 is a flowchart showing a process flow of an example of the opening and closing control of the shutoff valve SV and the release valve 72, taking into consideration the detection of fuel gas by the vent pipe internal gas detector 10a. The flowchart in FIG. 9 is the same as FIG. 8 except that steps S3-2, S5, and S6 have been added. Note that the control unit 12a is in a state of issuing a close command to the release valve 72.

[0153] In S1, the tank compartment internal gas detector 44a detects that the fuel gas concentration in the tank compartment 40 is below the standard value (No in S1), in S3 the battery compartment internal gas detector 34a detects that the fuel gas concentration in the fuel cell compartment 30 is below the standard value (No in S3), and in S3-1 the upper duct compartment internal gas detector 88 detects that the fuel gas concentration in the duct compartment 90 is below the standard value (No in S3-1), and if the vent pipe internal gas detector 10a detects that the fuel gas inside the vent pipe 10 is above the standard value (No in S3-2), the control unit 12a determines that the release valve 72 is malfunctioning (S5). The reason why the control unit 12a makes such a determination is as follows.

[0154] The fuel gas detected by the vent pipe internal gas detector 10a is any one of the following: (A) fuel gas that leaks inside the tank compartment 40 and flows into the vent pipe 10; (B) fuel gas that leaks inside the duct compartment 90 and flows into the vent pipe 10 via the vent pipe communication part 81; (C) fuel gas that leaks inside the fuel cell compartment 30 and then flows into the vent pipe 10 via the duct compartment 90 and the vent pipe communication part 81; or (D) fuel gas that flows into the vent pipe 10 through the fuel gas discharge pipe 71. Of these, the fuel gas (A) is always detected by the tank compartment internal gas detector 44a. Furthermore, the fuel gases (B) and (C) are always detected by the upper duct compartment internal gas detector 88. Therefore, if the tank compartment internal gas detector 44a and the upper duct compartment internal gas detector 88 do not detect fuel gas, but the vent pipe internal gas detector 10a does detect fuel gas, this necessarily means that the fuel gas is not fuel gas (A) to (C), but fuel gas (D).

[0155] Here, for example, when the control unit 12a issues an open command to the release valve 72 and the release valve 72 is open, the fuel gas flows through the fuel gas discharge pipe 71 to the vent pipe 10 via the release valve 72. Therefore, it is natural that the vent pipe internal gas detector 10a detects fuel gas. However, if the control unit 12a issues a close command to the release valve 72 and the vent pipe internal gas detector 10a detects fuel gas, this means that the release valve 72 is not completely closing the flow path of the fuel gas discharge pipe 71. Therefore, if the answer is No in S3-2, the control unit 12a can determine that the release valve 72 is malfunctioning (S5).

[0156] If the control unit 12a determines in S5 that the release valve 72 is malfunctioning, the control unit 12a issues a notification to the outside (S6). The notification may include displaying on a monitor, outputting an alarm sound, sending information to an external terminal (for example, sending an email), etc.

[0157] As described above, the control unit 12a determines whether or not there is a malfunction in the release valve 72 based on the detection results of the fuel gas detector (e.g., the tank compartment internal gas detector 44a, the upper duct compartment internal gas detector 88) and the vent pipe internal gas detector 10a (S1, S3-1, S3-2), and if there is a malfunction, notifies the outside (S5, S6).

[0158] If the release valve 72 is out of order, an external notification can be sent to prompt a maintenance person to inspect, repair, or replace the release valve 72.

[0159] In particular, when the fuel gas detectors (e.g., the tank compartment internal gas detector 44a and the upper duct compartment internal gas detector 88) in the tank compartment 40 and the duct compartment 90 do not detect fuel gas whose concentration is equal to or greater than the standard value and a command to close is issued to the release valve 72, the control unit 12a determines that the release valve 72 has failed (S5).

[0160] When no fuel gas leak is detected in the tank compartment 40 or the duct compartment 90 and a command to close the release valve 72 has been issued, but the vent pipe internal gas detector 10a detects fuel gas with a concentration equal to or greater than the standard value, there is a high possibility that fuel gas is leaking from the release valve 72 and flowing into the vent pipe 10. Therefore, the above determination method can reliably determine whether or not the release valve 72 is malfunctioning.

[0161] [7. Other] In this embodiment, gaseous fuel gas is used as the fuel supplied from the fuel tank 41 to the fuel cell 31, but the fuel is not limited to gas and may be liquid. When liquid fuel is used, if the liquid fuel leaks from the piping, the leaked liquid fuel vaporizes and becomes gas (fuel gas).

[0162] In this embodiment, the fuel cell ship SH has been described as having a configuration in which the duct section 90 is provided, but the duct section 90 does not have to be provided. For example, if vent pipes are provided corresponding to each of the tank section 40 and the fuel cell section 30, the installation of the duct section 90 can be omitted (because there is no need to ensure a flow path from the fuel cell section 30 to the vent pipe 10). In this case, for example, the opening and closing control of the shutoff valve SV and the release valve 72 shown in Figures 3 to 7 becomes effective.

[0163] However, in a configuration in which the fuel cell ship SH has a duct section 90, as in this embodiment, the air inside each section of the fuel cell ship SH (tank section 40, fuel cell section 30, duct section 90) or fuel gas in the event of leakage can be collected in the vent pipe 10 that communicates with the tank section 40 and the duct section 90 and discharged outside the ship. This reduces the number of parts and the number of dangerous locations specified by ship safety regulations compared to a configuration in which a separate vent pipe is provided in the fuel cell section 30, for example, making it possible to configure the fuel cell ship SH more compactly.

[0164] Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these, and the invention can be expanded or modified without departing from the spirit of the invention. [Industrial Applicability]

[0165] The present invention can be used in, for example, a fuel cell ship. [Explanation of symbols]

[0166] 1. Hull 6 Propulsion device 10 Vent pipe 10a Vent pipe internal gas detector 12a Control section 30 fuel cell compartment 31 Fuel Cell 32 Fuel gas supply piping (fuel supply piping) 33 Fuel cell side shutoff valve 34a Gas detector inside battery compartment (fuel gas detector) 40 Tank Compartment 41 Fuel tank 43 Tank side shutoff valve 44a Tank compartment internal gas detector (fuel gas detector) 70 Lower Duct Section (Duct Section) 71 Fuel gas exhaust piping (fuel exhaust piping) 72 Release valve 73 Lower duct compartment internal gas detector (fuel gas detector) 80 Upper Duct Section (Duct Section) 88 Upper duct compartment internal gas detector (fuel gas detector) 90 Duct Section SH fuel cell ship SV shutoff valve

Claims

1. a fuel cell for generating electricity; A power generation system that supplies power supplied from the fuel cell to a propulsion device or onboard equipment, a fuel cell compartment in which the fuel cell is installed; a tank compartment in which a fuel tank containing the fuel is installed; a fuel supply pipe for supplying the fuel from the fuel tank to the fuel cell, the fuel supply pipe has at least two shutoff valves, a tank-side shutoff valve installed in the tank compartment and a fuel cell-side shutoff valve installed in the fuel cell compartment; a fuel discharge pipe branching off from the fuel supply pipe between the tank-side shutoff valve and the fuel cell-side shutoff valve; a release valve installed in the fuel discharge pipe, When a fuel gas detector detects that the concentration of the fuel gas is equal to or higher than a specified value, the power generation system closes the tank-side shutoff valve and the fuel cell-side shutoff valve, while opening the release valve.

2. The power generation system according to claim 1 , wherein the fuel gas detector is installed in each of the compartments.

3. 3. The power generation system according to claim 2, wherein when at least one of the fuel gas detectors detects that the concentration of the fuel gas is equal to or greater than the predetermined standard value, the shutoff valves in all compartments are closed.

4. 4. The power generation system according to claim 1, wherein after the release valve is opened, the release valve is closed when the pressure in the fuel supply pipe reaches a predetermined pressure.

5. The power generation system according to claim 1 , wherein the discharge valve is closed after a predetermined time has elapsed since the discharge valve was opened.

6. a duct section that houses a portion of the fuel supply piping; the fuel gas detector is further installed in the duct compartment in addition to the tank compartment and the fuel cell compartment; 4. The power generation system according to claim 3, wherein the tank-side shutoff valve and the fuel cell-side shutoff valve are closed when the fuel gas detector in the duct section detects that the concentration of the fuel gas is equal to or greater than the specified value.

7. a vent pipe that guides the fuel gas discharged from the fuel discharge pipe through the release valve to the outside; a vent pipe internal gas detector that detects the fuel gas inside the vent pipe, 7. The power generation system according to claim 6, wherein the presence or absence of a malfunction of the release valve is determined based on the detection results of the fuel gas detector and the vent pipe internal gas detector, and if a malfunction is detected, an external notification is issued.

8. 8. The power generation system according to claim 7, wherein the release valve is determined to have failed when the vent pipe internal gas detector detects the fuel gas having a concentration equal to or higher than the standard value in the tank compartment and the duct compartment while each fuel gas detector does not detect the fuel gas having a concentration equal to or higher than the standard value and a closure command is issued to the release valve.

Images