Fuel cell ship

Abstract

To provide a fuel battery ship that makes it possible, when fuel gas leakage occurs at a fuel battery, to inhibit leaked fuel gas from invading and residing in a cooling medium tank.SOLUTION: A fuel battery ship comprises a cooling system for cooling a fuel battery. The cooling system includes: a cooling medium tank that stores a cooling medium; a cooling medium circulation pipeline for making the cooling medium circulate between the fuel battery and the cooling medium tank; a cooling tank internal gas detector provided in the cooling medium tank; a cooling tank internal gas discharge pipeline connected to the cooling medium tank; and a cooling tank internal gas discharge valve provided on the cooling tank internal gas discharge pipeline. The fuel battery ship comprises a control unit for controlling opening / closing of the cooling tank internal gas discharge valve. The control unit opens the cooling tank internal gas discharge valve when the cooling tank internal gas detector detects a fuel gas concentration in the cooling medium tank being higher than a predetermined standard value.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a fuel cell ship. [Background technology]

[0002] 2. Description of the Related Art Conventionally, fuel cell ships have 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 electricity generated by the fuel cell (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-92815 A Summary of the Invention [Problem to be solved by the invention]

[0004] A fuel cell generates heat as it generates electricity. To maintain an appropriate power generation efficiency of the fuel cell, it is desirable to cool the fuel cell, for example, by supplying a cooling medium (e.g., cooling water). However, in such a configuration, if a fuel gas leak occurs in the fuel cell for some reason, the leaked fuel gas may enter the cooling medium tank via the piping for circulating the cooling medium. Considering that the fuel gas is flammable and there is a risk of explosion, it is undesirable for the leaked fuel gas to stagnate in the cooling medium tank.

[0005] The present invention has been made to solve the above-mentioned problems, and its object is to provide a fuel cell ship that can prevent leaked fuel gas from entering and stagnating in a cooling medium tank when a fuel gas leak occurs in a fuel cell. [Means for solving the problem]

[0006] A fuel cell ship according to one aspect of the present invention is a fuel cell ship comprising a fuel cell that generates electricity through an electrochemical reaction of fuel, and a propulsion device that generates propulsive force for the hull using the electricity supplied from the fuel cell, and further comprising a cooling system that cools the fuel cell, the cooling system including a cooling medium tank that contains a cooling medium, a cooling medium circulation piping that circulates the cooling medium between the fuel cell and the cooling medium tank, a cooling tank internal gas detector installed in the cooling medium tank, a cooling tank internal gas release piping connected to the cooling medium tank, and a cooling tank internal gas release valve installed in the cooling tank internal gas release piping, the fuel cell ship further comprising a control unit that controls the opening and closing of the cooling tank internal gas release valve, and the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value. Effect of the Invention

[0007] According to the above configuration, when a fuel gas leak occurs in the fuel cell, the leaked fuel gas can be prevented from entering and remaining in the cooling medium tank. [Brief description 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; [Diagram 2] FIG. 2 is an explanatory diagram illustrating a schematic internal structure of the fuel cell ship. [Diagram 3] 2 is an explanatory diagram showing a schematic configuration of a fuel cell provided in the fuel cell ship; FIG. [Figure 4] 6 is a flowchart showing a process flow for controlling the opening and closing of a gas release valve inside a cooling tank provided in the fuel cell ship. [Diagram 5] FIG. 2 is an explanatory diagram illustrating a schematic configuration of a main part of the fuel cell ship. [Figure 6] 5 is an explanatory diagram showing a schematic diagram of another configuration of the main part of the fuel cell ship. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 to the bow of the fuel cell ship is defined as the "front", and the direction from the bow to the stern is defined as the "rear". 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 by the operator is defined as the "left", and the right side is defined as the "right". Furthermore, the upstream side of the direction of gravity perpendicular to the fore-aft and left-right directions is defined as the "up" and the downstream side is defined as the "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 Fig. 1. Fig. 1 is an explanatory diagram showing the general configuration of the fuel cell ship SH. The fuel cell ship SH includes 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 cooling system 7, 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, and is, for example, 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 the 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. Details of the fuel cell system 3 will be described later.

[0013] The fuel gas storage unit 4 stores the fuel gas to be supplied to the fuel cell system 3. Specifically, the fuel gas storage unit 4 has a fuel tank 41 (see FIG. 2) that stores fuel gas as a fuel. The fuel gas is supplied from the fuel tank 41 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-hydrogen 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 supply 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 electric power supplied from a fuel cell 31 (see FIG. 2 ) of the fuel cell system 3, which will be described later, 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 by electric power supplied from the fuel cell 31.

[0016] The propulsion device 6 may be driven only by power supplied from the storage battery in 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 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 according 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, and a propulsive force is generated in 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, solenoid valves, pumps, etc. The peripheral devices 11 also include electrical devices such as lighting devices 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 storage battery system 5, the propulsion device 6, the cooling system 7, 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 PLC (Programmable Logic Controller), but may also be an ECU (Electronic Control Unit). The control device 12 is supplied with power from a battery (for example, a lead battery) not shown, or from a storage battery of the storage battery system 5.

[0020] The control device 12 has a control unit 12a and a storage unit 12b. The control unit 12a includes a processor such as a CPU (Central Processing Unit). The storage unit 12b includes a storage device and stores data and computer programs. Specifically, the storage 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 storage unit 12b may include a removable medium. The storage 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, the cooling system 7 and multiple peripheral devices 11 by executing computer programs stored in the storage device of the memory unit 12b.

[0022] The cooling system 7 has a function of cooling the fuel cell system 3, particularly the fuel cell 31. In other words, the fuel cell ship SH of this embodiment is equipped with the cooling system 7 that cools the fuel cell 31. The cooling system 7 will be described in detail later.

[0023] [2. Details of the fuel cell system] Next, a detailed description will be given of the fuel cell system 3. Fig. 2 is an explanatory diagram that shows a schematic internal structure of the fuel cell ship SH.

[0024] The fuel cell ship SH includes an engine room 13 and a fuel room 14. The engine room 13 and the fuel room 14 are disposed below the deck 1a of the hull 1. In other words, the engine room 13 and the fuel room 14 are disposed between the deck 1a and the bottom plate 1b of the hull 1. The bottom plate 1b is located between the deck 1a and the ship bottom 1c (see FIG. 1).

[0025] The engine room 13 is located on the bow side of the fuel room 14. The engine room 13 and the fuel room 14 are separated by a bulkhead (not shown). The bulkhead is made of, for example, fiber reinforced plastics (FRP: Fiber Reinforced Plastics), but may also be a steel plate. The fuel tank 41 of the above-mentioned fuel gas storage section 4 is located within the fuel room 14. In this way, the fuel cell ship SH is equipped with the fuel tank 41 that stores fuel.

[0026] 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).

[0027] The fuel cell 31 generates electricity (specifically, DC power) through an electrochemical reaction between a fuel gas, which is an example of a 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 a fuel cell 31 that generates electricity through an electrochemical reaction of the fuel.

[0028] Fig. 3 is an explanatory diagram showing a schematic configuration of a fuel cell 31. The fuel cell 31 is, for example, a polymer electrolyte fuel cell (PEFC) and is a fuel cell stack formed by stacking a plurality of cells 310. For simplicity, Fig. 3 shows the fuel cell 31 as having two cells 310. Each cell 310 of the fuel cell 31 has a solid polymer electrolyte membrane 311, an anode electrode 312, a cathode electrode 313, and a pair of separators 314a and 314b.

[0029] The anode 312 and the cathode 313 sandwich a solid polymer electrolyte membrane 311. The anode 312 is a negative electrode (fuel electrode). The anode 312 includes an anode catalyst layer and a gas diffusion layer. The cathode 313 is a positive electrode (air electrode). The cathode 313 includes a cathode catalyst layer and a gas diffusion layer. The anode 312, the solid polymer electrolyte membrane 311, and the cathode 313 constitute a membrane electrode assembly (MEA). A pair of separators 314a and 314b sandwich the membrane electrode assembly.

[0030] Each of the separators 314a and 314b is made of, for example, SUS (stainless steel) and has uneven ribs that form a plurality of grooves on both sides. The grooves located on one side (opposing the anode 312) of the separator 314a form a flow path CH1 for the fuel gas. The grooves located on one side (opposing the cathode 313) of the separator 314b form a flow path CH2 for the oxidizer gas. In addition, the grooves on the other side of the separator 314b of an arbitrary cell 310 (for example, cell 310B) and the grooves on the other side of the separator 314a of the adjacent cell 310 (for example, cell 310A) form a flow path CH3 for the cooling medium, which will be described later. Note that the flow paths CH1 and CH3 are provided with various detectors (pressure sensors, temperature sensors, etc.), which will be described later.

[0031] 3, the cooling medium flow path CH3 is provided between adjacent cells 310, but it is not necessary to sandwich the flow path CH3 between each cell 310. If each cell 310 can be cooled to an appropriate temperature, a configuration in which the cooling medium flow path CH3 is sandwiched between every several stacked cells is also possible.

[0032] In the above-mentioned configuration of the fuel cell 31, for example, on the anode 312 side of the cell 310B, hydrogen contained in the fuel gas flowing through the flow channel CH1 is decomposed into hydrogen ions and electrons by a catalyst. The hydrogen ions permeate the solid polymer electrolyte membrane 311 and move to the cathode 313 side. Since the uneven ribs of the separator 314a of the cell 310B are in contact with the anode 312 across the flow channel CH1, the electrons generated at the anode 312 move to the separator 314a. Since the separator 314a of the cell 310B and the separator 314b sandwiching the flow channel CH3 of the cooling medium are in contact with each other at their ribs, the above-mentioned electrons move from the separator 314a to the separator 314b. The electrons that have moved to the separator 314b pass through the external circuit 315 and move to the separator 314a at the opposite end in the stacking direction. This generates a current (generates electricity).

[0033] The separator 314a and the separator 314b of the cell 310A sandwiching the cooling medium flow path CH3 are in contact with each other at their ribs, so the electrons move from the separator 314a to the separator 314b of the cell 310A. The uneven ribs of the separator 314b are in contact with the cathode 313 across the oxidant gas flow path CH2, so the electrons that have moved to the separator 314b move to the cathode 313. On the cathode 313 side, oxygen contained in the oxidant gas flowing through the flow path CH2 combines with the electrons and hydrogen ions that have passed through the solid polymer electrolyte membrane to generate water. The generated water is discharged overboard via the discharge pipe 31a (see FIG. 2).

[0034] The fuel cell 31 supplies the generated electric power to the propulsion device 6 and the peripheral device 11 shown in Fig. 1. The fuel cell 31 may also supply the generated electric power to the propulsion device 6 and the peripheral device 11 indirectly via a circuit such as a DC / DC converter.

[0035] 2 is a fuel supply pipe for supplying the fuel gas stored in the fuel tank 41 of the fuel gas storage unit 4 to the anode 312 (see FIG. 3) of the fuel cell 31. In other words, the fuel cell ship SH is provided with the fuel gas supply pipe 32 as a fuel supply pipe for supplying fuel from the fuel tank 41 to the fuel cell 31.

[0036] The fuel cell side shutoff valve 33 is a shutoff valve 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 in the fuel gas supply pipe 32 in the fuel cell compartment 30, which will be described later, but two or more may be provided.

[0037] 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 disposed in the engine room 13.

[0038] 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 have, 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 surface, bottom surface, front surface, back surface, and side surface of the fuel cell compartment 30 can be arbitrarily determined. In addition, the shape of the fuel cell compartment 30 is not particularly limited as long as it has a space capable of accommodating the fuel cell 31. The fuel cell compartment 30 can also be regarded as a container, a chamber, or a 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 an iron plate.

[0039] A battery compartment air intake 30e is provided as an opening in a side wall 30d of the fuel cell compartment 30. The battery compartment air intake 30e is connected to a battery compartment air intake pipe 35. The battery compartment air intake pipe 35 extends from the battery compartment air intake 30e to the deck 1a and is exposed from the upper surface of the deck 1a. Note that the battery compartment air intake 30e may be provided in an outer wall of the fuel cell compartment 30 other than the side wall 30d.

[0040] Meanwhile, a battery compartment exhaust port 30f is provided as an opening in the side wall 30c of the fuel cell compartment 30. The battery compartment exhaust port 30f is connected to the communication section 36. The communication section 36 communicates with a duct section (not shown) that forms an exhaust passage. The duct section also communicates with a vent pipe (not shown) that communicates with the outside of the ship. As a result, air that has entered the inside of the fuel cell compartment 30 from the battery compartment air supply pipe 35 via the battery compartment air supply port 30e is exhausted outside the ship via the battery compartment exhaust port 30f, the communication section 36, the duct compartment, and the vent pipe. As a result, the inside of the fuel cell compartment 30 is ventilated.

[0041] The fuel cell compartment 30 has an internal space that is sealed except for a fuel cell compartment air inlet 30e and a fuel cell compartment air outlet 30f.

[0042] A portion of the fuel gas supply pipe 32 and a fuel cell-side shutoff valve 33 are housed within the fuel cell compartment 30. The fuel cell compartment 30 also houses a cell compartment internal gas detector 34a and a cell compartment internal fire detector 34b.

[0043] The battery 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 battery compartment internal gas detector 34a is configured with a hydrogen gas detection sensor.

[0044] 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 as a 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 inside 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 disposed at the most downstream side of the flow path through which the fuel gas flows when the fuel gas leaks inside the fuel cell compartment 30.

[0045] 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 controller 12a. This enables the controller 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.

[0046] 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.

[0047] 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 that a fire has broken out to the controller 12a. In this case, the controller 12a can control 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 can minimize the risk of an explosion in the fuel cell compartment 30 due to ignition of the fuel gas.

[0048] The above fuel cell system 3 will be further described. The fuel cell system 3 has an oxidant gas flow rate regulator 321, an off-gas circulation unit 322, a gas-liquid separator 323, and a discharge unit 324. The oxidant gas flow rate regulator 321, the off-gas circulation unit 322, and the discharge unit 324 are examples of peripheral devices 11. The control unit 12a controls the oxidant gas flow rate regulator 321, the off-gas circulation unit 322, and the discharge unit 324. The fuel cell system 3 further has a discharge pipe 31a, an oxidant gas pipe 31b, an off-gas circulation pipe 31c, and a connection pipe 31d. A manifold is formed inside the fuel cell 31 for circulating the fuel gas, the oxidant gas, and a cooling medium, which will be described later.

[0049] The oxidizing gas flow rate adjusting unit 321 supplies the oxidizing gas to the cathode 313 (see FIG. 3) of the fuel cell 31. Specifically, the oxidizing gas flow rate adjusting unit 321 adjusts the flow rate of the oxidizing gas supplied to the fuel cell 31. Typically, the oxidizing gas flow rate adjusting unit 321 is an air compressor that compresses the oxidizing gas.

[0050] The oxidizing gas pipe 31 b guides the oxidizing gas supplied from the oxidizing gas flow rate regulator 321 to the cathode 313 of the fuel cell 31 .

[0051] The above-mentioned exhaust pipe 31a is connected to an exhaust manifold on the cathode 313 side provided inside the fuel cell 31. The exhaust pipe 31a guides the oxidant off-gas and water exhausted from the fuel cell 31 to the atmosphere. The oxidant off-gas refers to exhaust from the cathode 313. In other words, the oxidant off-gas is cathode off-gas.

[0052] The gas-liquid separation unit 323 separates water contained in the fuel off-gas discharged from the fuel cell 31, and discharges the water to the connection pipe 31d. In addition, the gas-liquid separation unit 323 discharges surplus fuel gas, which is the fuel off-gas after water has been separated, to the off-gas circulation pipe 31c. Typically, the gas-liquid separation unit 323 is a gas-liquid separator. The fuel off-gas refers to exhaust from the anode electrode 312 (see FIG. 3) of the fuel cell 31. In other words, the fuel off-gas is anode off-gas.

[0053] The off-gas circulation unit 322 is disposed in the off-gas circulation piping 31c. The off-gas circulation unit 322 discharges the excess fuel gas discharged from the gas-liquid separation unit 323 to the fuel gas supply piping 32. Then, the fuel gas supply piping 32 supplies the excess fuel gas to the fuel cell 31. Typically, the off-gas circulation unit 322 is a pump. Note that, for example, the off-gas circulation unit 322 may be an ejector.

[0054] The discharge unit 324 is disposed in the connection pipe 31d. The discharge unit 324 discharges the water separated by the gas-liquid separation unit 323. In addition, the discharge unit 324 discharges a portion of the fuel off-gas discharged from the fuel cell 31, that is, the remaining gas and water that are not supplied to the off-gas circulation pipe 31c. Typically, the discharge unit 324 is a purge valve.

[0055] The water and fuel off-gas discharged from the discharge section 324 are discharged through the connection pipe 31d to the discharge pipe 31a, and together with the oxidant off-gas (cathode off-gas) discharged from the fuel cell 31, are guided from the discharge pipe 31a to the atmosphere.

[0056] [3. Details of the cooling system] Next, details of the cooling system 7 will be described with continued reference to Fig. 2. The cooling system 7 includes a cooling medium tank 71, a cooling medium circulation pipe 72, a cooling tank internal gas detector 73, a cooling tank internal gas release pipe 74, and a cooling tank internal gas release valve 75.

[0057] The cooling medium tank 71 is a container that contains a cooling medium. The cooling medium is, for example, an antifreeze liquid having low electrical conductivity. The antifreeze liquid is, for example, a liquid obtained by mixing pure water and ethylene glycol in a predetermined ratio.

[0058] The cooling medium tank 71 is installed inside the engine room 13, outside the fuel cell compartment 30. In this way, since the cooling medium tank 71 is installed in the engine room 13, it can also be said that the engine room 13 constitutes a cooling medium installation compartment. Therefore, it can be said that the fuel cell ship SH is equipped with a cooling medium installation compartment (engine room 13) in which the cooling medium tank 71 is installed.

[0059] The above-mentioned fuel gas supply pipe 32 extends from the fuel chamber 14 to the engine room 13, and is connected to the fuel cell 31 in the fuel cell compartment 30. In other words, the fuel gas supply pipe 32 passes through the cooling medium installation compartment.

[0060] Further, the engine room 13, which is a cooling medium installation section, has a ventilation opening 13a communicating with the outside of the ship. The ventilation opening 13a is an air supply and exhaust opening formed by penetrating the deck 1a which is the upper wall of the engine room 13. In this embodiment, the ventilation opening 13a is provided on each of the starboard side and the port side of the ship 1. When the air compressor (not shown) in the engine room 13 is not driven, for example, outside air is taken into the engine room 13 from the ventilation opening 13a on the starboard side. Then, the air inside the engine room 13 is exhausted outside the ship from the ventilation opening 13a on the port side. Conversely, outside air may be taken into the engine room 13 from the ventilation opening 13a on the port side and exhausted outside the ship from the ventilation opening 13a on the starboard side. In either of the above air flows, the inside of the engine room 13 is ventilated. In addition, there are cases where intake and exhaust are performed only through the starboard side ventilation opening 13a, and cases where intake and exhaust are performed only through the port side ventilation opening 13a. On the other hand, when the air compressor in the engine room 13 is running, the air compressor draws air into the engine room 13 through the starboard and port side ventilation openings 13a.

[0061] The cooling medium circulating pipe 72 is a pipe for circulating the cooling medium between the fuel cell 31 and the cooling medium tank 71. A cooling medium circulating unit 76 and a heat exchanger 77 are arranged in the middle of the cooling medium circulating pipe 72. The cooling medium circulating unit 76 is composed of, for example, a pump. When the cooling medium circulating unit 76 is driven, the cooling medium flows through the cooling medium circulating pipe 72, and the cooling medium circulates between the fuel cell 31 and the cooling medium tank 71. The cooling medium is supplied to the fuel cell 31, so that the fuel cell 31 is cooled. The cooling medium used to cool the fuel cell 31 passes through the cooling medium circulating pipe 72, is cooled by heat exchange in the heat exchanger 77, and is then returned to the cooling medium tank 71. The heat exchanger 77 may be installed in the cooling medium circulating pipe 72 between the cooling medium tank 71 and the cooling medium circulating unit 76.

[0062] Although the cooling medium circulator 76 is arranged inside the fuel cell compartment 30 in FIG. 2, it may be arranged outside the fuel cell compartment 30 inside the engine room 13.

[0063] Thus, the cooling system 7 includes the cooling medium tank 71 that stores the cooling medium, and the cooling medium circulation piping 72 that circulates the cooling medium between the fuel cell 31 and the cooling medium tank 71 .

[0064] The cooling tank internal gas detector 73 is a fuel gas detector that is installed in the upper interior of the cooling medium tank 71 and detects the fuel gas present inside the cooling medium tank 71. For example, when the fuel gas is hydrogen gas, the cooling tank internal gas detector 73 is composed of a hydrogen gas detection sensor.

[0065] The fuel gas present in the cooling medium tank 71 may be, for example, fuel gas that has leaked from the fuel cell 31 and entered the cooling medium tank 71 via the cooling medium circulation pipe 72. The detection result of the fuel gas by the cooling tank internal gas detector 73 (for example, information on the concentration of the fuel gas) is sent to the control unit 12a. As a result, the control unit 12a can determine whether or not there is a fuel gas leak in the fuel cell 31 based on the detection result by the cooling tank internal gas detector 73, and if there is a leak, can perform control to, for example, stop power generation in the fuel cell 31.

[0066] The cooling tank internal gas release piping 74 is connected to the cooling medium tank 71 and is a piping for releasing to the outside the fuel gas present inside the cooling medium tank 71. The outlet of the cooling tank internal gas release piping 74, that is, the end of the cooling tank internal gas release piping 74 opposite to the connection side with the cooling medium tank 71, constitutes a gas release port 74a for releasing the fuel gas.

[0067] The gas discharge port 74a is located above the electric equipment EM in the cooling medium installation section (engine room 13). The ventilation opening 13a of the engine room 13 is located above the gas discharge port 74a. The reason for specifying such a positional relationship will be described later. The electric equipment EM is equipment that constitutes the peripheral equipment 11. Specific examples of the electric equipment EM include an air compressor, a junction box that relays the generated power of the fuel cell 31 between the power conversion device 6a (see FIG. 1), an inverter, a converter, and the like.

[0068] The cooling tank internal gas release valve 75 is installed in the cooling tank internal gas release piping 74, and opens or closes the flow path of the fuel gas flowing through the cooling tank internal gas release piping 74. The opening and closing of the cooling tank internal gas release valve 75 is controlled by the control unit 12a.

[0069] Thus, the cooling system 7 has a cooling tank internal gas detector 73 installed in the cooling medium tank 71, a cooling tank internal gas release piping 74 connected to the cooling medium tank 71, and a cooling tank internal gas release valve 75 installed in the cooling tank internal gas release piping 74. The fuel cell ship SH also has a control unit 12a that controls the opening and closing of the cooling tank internal gas release valve 75.

[0070] Next, details of the opening / closing control of the cooling tank internal gas release valve 75 by the control unit 12a will be described with reference to Fig. 4. Fig. 4 is a flowchart showing the flow of processing by the opening / closing control of the cooling tank internal gas release valve 75.

[0071] When the cooling tank internal gas detector 73 detects that the concentration of fuel gas (e.g., hydrogen gas) in the cooling medium tank 71 is equal to or higher than the standard value (Yes in S1), the control unit 12a opens the cooling tank internal gas release valve 75 (S2). In this case, the fuel gas present in the cooling medium tank 71 passes through the cooling tank internal gas release piping 74 and is released from the gas release port 74a. Since the fuel gas is light, the fuel gas released from the gas release port 74a in the engine room 13 rises and is exhausted outside the ship via the ventilation port 13a of the engine room 13.

[0072] The standard value may be, for example, 40% LEL, but may be appropriately determined based on experiments or experience.

[0073] On the other hand, when the cooling tank internal gas detector 73 detects that the concentration of the fuel gas in the cooling medium tank 71 is below the standard value (No in S1), the control unit 12a closes the cooling tank internal gas release valve 75 (S3). This keeps the inside of the cooling medium tank 71 sealed.

[0074] As described above, when the cooling-tank internal gas detector 73 detects that the concentration of fuel gas (fuel in a gaseous state) in the cooling medium tank 71 is equal to or higher than a predetermined standard value, the control unit 12a opens the cooling-tank internal gas release valve 75 (S1, S2). As a result, even if a fuel gas leak occurs in the fuel cell 31 for some reason and the leaked fuel gas enters the cooling medium tank 71 via the cooling medium circulation pipe 72, the fuel gas is released from the cooling-tank internal gas release pipe 74 via the cooling-tank internal gas release valve 75. This makes it possible to reduce the situation in which the leaked fuel gas remains in the cooling medium tank 71.

[0075] As described above, the gas discharge port 74a of the cooling tank internal gas discharge piping 74 is located above the electric equipment EM in the engine room 13 in which the cooling medium tank 71 is installed (see FIG. 2). In this case, when the fuel gas leaking from the fuel cell 31 and entering the cooling medium tank 71 is discharged from the gas discharge port 74a of the cooling tank internal gas discharge piping 74, the fuel gas with a light specific gravity (e.g., hydrogen gas) rises, so that the fuel gas is less likely to come into contact with the electric equipment EM located below. This can reduce the risk of the discharged fuel gas igniting due to the electric equipment EM.

[0076] In addition, the ventilation opening 13a of the engine room 13 is located above the gas discharge opening 74a (see FIG. 2). As a result, the fuel gas with a light specific gravity discharged from the gas discharge opening 74a rises directly from the gas discharge opening 74a and is quickly (efficiently) discharged to the outside of the engine room 13 via the ventilation opening 13a. This makes it possible to reliably reduce the risk of ignition of the fuel gas in the engine room 13 by the electric equipment EM.

[0077] In addition, because the fuel gas passes through the fuel gas supply pipe 32, there is a possibility that the fuel gas may leak from the fuel gas supply pipe 32 for some reason. Meanwhile, there is a possibility that the fuel gas leaking from the fuel cell 31 may enter and collect in the cooling medium tank 71 via the cooling medium circulation pipe 72. For this reason, it cannot be denied that the fuel gas collected in the cooling medium tank 71 may leak from the cooling medium tank 71 for some reason.

[0078] As in this embodiment, the fuel gas supply pipe 32 is positioned through the engine room 13 in which the cooling medium tank 71 is installed, so that the parts of the hull 1 where fuel gas may leak (the fuel gas supply pipe 32, the cooling medium tank 71) are concentrated in the same space (the engine room 13). This narrows the area where there is a risk of fuel gas leaking, compared to when, for example, the cooling medium tank 71 is installed in a location other than the engine room 13. This increases the degree of freedom in installation when installing electrical equipment outside the above-mentioned area. For example, even when an air supply fan is installed outside the ventilation opening 13a of the engine room 13 in order to actively ventilate the engine room 13, the area in which the air supply fan can be installed is wider. This increases the degree of freedom in installation.

[0079] 2, in this embodiment, the cooling medium tank 71 is connected to the top of the cooling medium circulation pipe 72. In other words, the cooling medium tank 71 is located at the top of the circulation path of the cooling medium flowing through the cooling medium circulation pipe 72. By defining the positional relationship (connection relationship) between the cooling medium tank 71 and the cooling medium circulation pipe 72 in this manner, the following effects can be obtained.

[0080] For example, if the cooling medium tank 71 is connected to a portion other than the top of the cooling medium circulation piping 72 (e.g., the bottom portion), when the control unit 12a opens the cooling tank internal gas release valve 75 based on the fuel gas detection results from the cooling tank internal gas detector 73, the cooling medium in the cooling medium circulation piping 72 may flow into the cooling medium tank 71 due to its own weight and flow out from the gas release port 74a of the cooling tank internal gas release piping 74, resulting in a "cooling medium leak."

[0081] Since the cooling medium tank 71 is connected to the top of the cooling medium circulation pipe 72 and is located at the top of the cooling medium circulation path, it is possible to prevent the cooling medium in the cooling medium circulation pipe 72 from flowing into the cooling medium tank 71 due to its own weight even when the control unit 12a opens the cooling tank internal gas release valve 75. This makes it possible to prevent the cooling medium from leaking when the cooling tank internal gas release valve 75 is opened.

[0082] In addition, when the cooling tank internal gas detector 73 detects that the concentration of fuel gas in the cooling medium tank 71 is below a predetermined standard value, the control unit 12a closes the cooling tank internal gas release valve 75 to seal the cooling medium tank 71 (S3).

[0083] When the operating temperature of the fuel cell 31 becomes high, there may be a case where pressurized water (pressurized cooling medium) is required to be supplied to the fuel cell 31 in order to quickly cool the fuel cell 31. For example, when the operating temperature of the fuel cell 31 exceeds 100°C, the liquid state (heat transfer coefficient is 10 times higher than that of the gas state) cannot be maintained unless the cooling medium is pressurized. When there is no leakage of fuel gas into the cooling medium tank 71, sealing the cooling medium tank 71 makes it possible to easily respond to the supply of such pressurized water. In other words, it becomes possible to pressurize the cooling medium in the cooling medium tank 71 and supply it to the fuel cell 31. In addition, since the cooling medium tank 71 is sealed, it is also possible to avoid problems that occur when the top of the cooling medium tank 71 is always open. For example, it is also possible to prevent the cooling medium from leaking out of the tank due to the rocking of the fuel cell ship SH while sailing, and to prevent impurities from being mixed into the cooling medium in the cooling medium tank 71.

[0084] In particular, the optimum operating temperature of the solid polymer electrolyte fuel cell 31 is around 80°C, but if it continues to be driven under high load, the operating temperature of the fuel cell 31 may reach 100°C or higher. Therefore, the above control, which seals the coolant tank 71 and enables the supply of pressurized water when there is no leakage of fuel gas into the coolant tank 71, is very effective when the operating temperature of the fuel cell 31 is 100°C or higher. In other words, when at least one of the temperature of the coolant supplied to the fuel cell 31 and the temperature of the coolant discharged from the fuel cell 31 is 100°C or higher, the above control, which seals the coolant tank 71 and enables the supply of pressurized water, is very effective.

[0085] The temperature of the cooling medium supplied to the fuel cell 31 can be monitored by a supply-side cooling medium temperature detection unit 331a shown in Figures 5 and 6. Meanwhile, the temperature of the cooling medium discharged from the fuel cell 31 can be monitored by a discharge-side cooling medium temperature detection unit 331b. The supply-side cooling medium temperature detection unit 331a and the discharge-side cooling medium temperature detection unit 331b are each constituted by a temperature sensor such as a thermistor.

[0086] [4. Control to prevent fuel gas leakage from fuel cells] 5 is an explanatory diagram showing a schematic configuration of the main parts of the fuel cell ship SH. The fuel cell ship SH may include a supply-side fuel gas pressure detection unit 332a and a supply-side cooling medium pressure detection unit 333a. The supply-side fuel gas pressure detection unit 332a is a supply-side fuel pressure detection unit that detects the pressure P1 (MPa) of the fuel (e.g., fuel gas) supplied to the fuel cell 31 (from the fuel tank 41). The supply-side cooling medium pressure detection unit 333a detects the pressure P2 (MPa) of the cooling medium supplied to the fuel cell 31 (from the cooling medium tank 71). The supply-side fuel gas pressure detection unit 332a and the supply-side cooling medium pressure detection unit 333a are both composed of pressure sensors.

[0087] It is desirable that the control unit 12a stops power generation of the fuel cell 31 when the pressure P1 of the fuel (e.g., fuel gas) becomes greater than the pressure P2 of the cooling medium based on the detection results of the supply side fuel gas pressure detection unit 332a and the supply side cooling medium pressure detection unit 333a.

[0088] When P1>P2, there is a possibility that fuel may leak into the cooling medium side on the fuel gas supply side (anode inlet side) of the fuel cell 31. When P1>P2, power generation of the fuel cell 31 is stopped, so that leakage of fuel from the fuel supply side of the fuel cell 31 into the cooling medium side can be suppressed.

[0089] Fig. 6 is an explanatory diagram showing a schematic diagram of another configuration of the main parts of the fuel cell ship SH. The fuel cell ship SH may further include a discharge side fuel gas pressure detection unit 332b and a discharge side cooling medium pressure detection unit 333b in addition to the supply side fuel gas pressure detection unit 332a and the supply side cooling medium pressure detection unit 333a shown in Fig. 5. The discharge side fuel gas pressure detection unit 332b is a discharge side fuel pressure detection unit that detects the pressure P3 (MPa) of the fuel (e.g., fuel gas) discharged from the fuel cell 31. The discharge side cooling medium pressure detection unit 333b detects the pressure P4 (MPa) of the cooling medium discharged from the fuel cell 31. Both the discharge side fuel gas pressure detection unit 332b and the discharge side cooling medium pressure detection unit 333b are composed of pressure sensors.

[0090] Here, the difference between the pressure P1 of the fuel (e.g., fuel gas) detected by the supply-side fuel gas pressure detection unit 332a and the pressure P2 of the cooling medium detected by the supply-side cooling medium pressure detection unit 333a is defined as a first pressure difference Pd1 (MPa). Also, the difference between the pressure P3 of the fuel (e.g., fuel gas) detected by the discharge-side fuel gas pressure detection unit 332b and the pressure P4 of the cooling medium detected by the discharge-side cooling medium pressure detection unit 333b is defined as a second pressure difference Pd2 (MPa).

[0091] It is desirable that the control unit 12a stops power generation by the fuel cell 31 when at least one of the first pressure difference Pd1 and the second pressure difference Pd2 becomes equal to or greater than a predetermined value Pth (MPa).

[0092] When Pd1 ≧ Pth, that is, for example, when (P1-P2) ≧ Pth, the fuel supply pressure is too high compared to the cooling medium supply pressure, so there is a possibility that the fuel will leak into the cooling medium on the fuel supply side (anode inlet side) of the fuel cell 31 and become mixed in. On the other hand, when Pd2 ≧ Pth, that is, for example, when (P3-P4) ≧ Pth, the fuel discharge pressure is too high compared to the cooling medium discharge pressure, so there is a possibility that the fuel will leak into the cooling medium on the fuel discharge side (anode outlet side) of the fuel cell 31 and become mixed in.

[0093] By stopping power generation in the fuel cell 31 when at least one of the conditions Pd1≧Pth and Pd2≧Pth is satisfied, it is possible to prevent fuel from leaking to the cooling medium side on at least one of the fuel supply side and discharge side of the fuel cell 31.

[0094] As described above, 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).

[0095] Although the embodiment of the present invention has been described above, the scope of the present invention is not limited to this, and the invention can be expanded or modified without departing from the spirit of the invention. [Industrial Applicability]

[0096] The present invention can be used, for example, in a fuel cell ship. [Explanation of symbols]

[0097] 1. Hull 6 Propulsion device 7. Cooling System 12a Control section 13 Engine room (coolant tank installation area) 13a Ventilation vent 31 Fuel Cell 32 Fuel gas supply piping (fuel supply piping) 41 Fuel Tank 71 Coolant tank 72 Coolant circulation piping 73 Cooling tank internal gas detector 74 Cooling tank internal gas release piping 74a Gas outlet 75 Cooling tank internal gas release valve 332a Supply side fuel gas pressure detection unit (supply side fuel pressure detection unit) 333a Supply side cooling medium pressure detection unit 332b Discharge side fuel gas pressure detection unit (discharge side fuel pressure detection unit) 333b Discharge side cooling medium pressure detection unit EM Electrical Equipment SH fuel cell ship

Claims

1. A fuel cell that generates electricity through an electrochemical reaction of fuel; a propulsion device that generates a propulsive force on a hull by electric power supplied from the fuel cell, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The fuel cell ship further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The fuel cell ship further includes a cooling medium tank installation section in which the cooling medium tank is installed, A fuel cell ship, wherein a gas discharge port of the gas discharge piping inside the cooling tank is located above electrical equipment in the cooling medium tank installation section.

2. The cooling medium tank installation section has a ventilation opening communicating with the outside of the ship, The fuel cell ship according to claim 1 , wherein the ventilation opening is located above the gas discharge opening.

3. A fuel tank for storing the fuel; a fuel supply pipe for supplying the fuel from the fuel tank to the fuel cell, The fuel cell ship according to claim 1 , wherein the fuel supply pipe passes through the cooling medium tank installation section.

4. A fuel cell ship as described in any of claims 1 to 3, wherein the cooling medium tank is located at the top of the circulation path of the cooling medium flowing through the cooling medium circulation piping.

5. A fuel cell that generates electricity through an electrochemical reaction of fuel; a propulsion device that generates a propulsive force on a hull by electric power supplied from the fuel cell, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The fuel cell ship further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The fuel cell ship includes: a supply-side fuel pressure detection unit that detects the pressure of the fuel supplied to the fuel cell; a supply-side cooling medium pressure detector that detects the pressure of the cooling medium supplied to the fuel cell; The control unit stops power generation by the fuel cell when the pressure of the fuel becomes greater than the pressure of the cooling medium.

6. A fuel cell that generates electricity through an electrochemical reaction of fuel; a propulsion device that generates a propulsive force on a hull by electric power supplied from the fuel cell, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The fuel cell ship further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The fuel cell ship includes: a supply-side fuel pressure detection unit that detects the pressure of the fuel supplied to the fuel cell; a supply-side cooling medium pressure detector that detects the pressure of the cooling medium supplied to the fuel cell; a discharge side fuel pressure detection unit that detects the pressure of the fuel discharged from the fuel cell; a discharge-side cooling medium pressure detector that detects the pressure of the cooling medium discharged from the fuel cell, a first pressure difference is a difference between a pressure of the fuel detected by the supply-side fuel pressure detection unit and a pressure of the cooling medium detected by the supply-side cooling medium pressure detection unit; a second pressure difference is defined as a difference between the pressure of the fuel detected by the discharge-side fuel pressure detection unit and the pressure of the cooling medium detected by the discharge-side cooling medium pressure detection unit, The control unit stops power generation by the fuel cell when at least one of the first pressure difference and the second pressure difference becomes equal to or greater than a predetermined value.

7. A fuel cell that generates electricity through an electrochemical reaction of fuel; a propulsion device that generates a propulsive force on a hull by electric power supplied from the fuel cell, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The fuel cell ship further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The control unit, when the cooling tank internal gas detector detects that the concentration of the fuel gas in the cooling medium tank is below a predetermined standard value, closes the cooling tank internal gas release valve to seal the cooling medium tank.

8. A fuel cell ship as described in claim 7, wherein at least one of the temperature of the cooling medium supplied to the fuel cell and the temperature of the cooling medium discharged from the fuel cell is 100°C or higher.

9. A power generation system including a fuel cell that generates power through an electrochemical reaction of a fuel, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The power generation system further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The power generation system further includes a cooling medium tank installation section in which the cooling medium tank is installed, a gas discharge port of the gas discharge pipe inside the cooling tank is located above electrical equipment in the cooling medium tank installation section.

10. A power generation system including a fuel cell that generates power through an electrochemical reaction of a fuel, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The power generation system further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The power generation system includes: a supply-side fuel pressure detection unit that detects the pressure of the fuel supplied to the fuel cell; a supply-side cooling medium pressure detector that detects the pressure of the cooling medium supplied to the fuel cell; The control unit stops power generation by the fuel cell when the pressure of the fuel becomes greater than the pressure of the cooling medium.

11. A power generation system including a fuel cell that generates power through an electrochemical reaction of a fuel, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The power generation system further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The power generation system includes: a supply-side fuel pressure detection unit that detects the pressure of the fuel supplied to the fuel cell; a supply-side cooling medium pressure detector that detects the pressure of the cooling medium supplied to the fuel cell; a discharge side fuel pressure detection unit that detects the pressure of the fuel discharged from the fuel cell; a discharge-side cooling medium pressure detector that detects the pressure of the cooling medium discharged from the fuel cell, a first pressure difference is a difference between a pressure of the fuel detected by the supply-side fuel pressure detection unit and a pressure of the cooling medium detected by the supply-side cooling medium pressure detection unit; a second pressure difference is defined as a difference between the pressure of the fuel detected by the discharge-side fuel pressure detection unit and the pressure of the cooling medium detected by the discharge-side cooling medium pressure detection unit, The control unit stops power generation by the fuel cell when at least one of the first pressure difference and the second pressure difference becomes equal to or greater than a predetermined value.

12. A power generation system including a fuel cell that generates power by an electrochemical reaction of a fuel, a cooling system for cooling the fuel cell; The cooling system comprises: A cooling medium tank that contains a cooling medium; a cooling medium circulating pipe for circulating the cooling medium between the fuel cell and the cooling medium tank; a cooling tank internal gas detector installed in the cooling medium tank; A cooling tank internal gas release pipe connected to the cooling medium tank; a cooling tank internal gas release valve installed in the cooling tank internal gas release piping; The power generation system further includes a control unit that controls opening and closing of the cooling tank internal gas release valve, the control unit opens the cooling tank internal gas release valve when the cooling tank internal gas detector detects that the concentration of the fuel gas, which is the gaseous state of the fuel in the cooling medium tank, is equal to or higher than a predetermined standard value; The control unit closes the cooling tank internal gas release valve to seal the cooling medium tank when the cooling tank internal gas detector detects that the concentration of the fuel gas in the cooling medium tank is below a predetermined standard value.

Images