JP2024064683A - Fuel Cell Power Generation Equipment - Google Patents

Abstract

[Problem] To provide a fuel cell power generation device applicable to various applications. [Solution] A fuel cell power generation device comprising: a fuel cell having an anode and an cathode, a fuel pipe supplying hydrogen to the anode, an air filter removing impurities contained in the air, an air compressor compressing the air supplied through the air filter and supplying it to the cathode, an exhaust pipe discharging exhaust gas generated by the fuel cell, and a first intermediate heat exchanger capable of exchanging heat between a first coolant for cooling the fuel cell and a different type of cold heat source. [Selected Figure] Figure 1

Description

This disclosure relates to a fuel cell power generation device.

Conventionally, a fuel cell module is known that includes a first heat exchanger that cools a first coolant discharged from a fuel cell stack, and a second heat exchanger that cools a second coolant discharged from several auxiliary devices, such as a converter that boosts the output voltage of the fuel cell stack. A specific example of a heat exchanger is a vehicle radiator (see, for example, Patent Document 1).

JP 2022-86272 A

However, if the heat exchanger is limited to the vehicle's radiator, it is difficult to apply the fuel cell power generation system to various applications.

This disclosure provides a fuel cell power generation device that can be used for a variety of purposes.

In a first aspect, a fuel cell power generator includes:
a fuel cell having an anode and an cathode;
a fuel pipe for supplying hydrogen to the fuel electrode;
An air filter that removes impurities from the air;
an air compressor that compresses the air supplied through the air filter and supplies the compressed air to the air electrode;
an exhaust pipe for discharging exhaust gas generated by the fuel cell;
The fuel cell is provided with a first intermediate heat exchanger capable of exchanging heat between a first coolant for cooling the fuel cell and a different type of cold heat source.

According to the first aspect, the fuel cell power generation device is provided with a first intermediate heat exchanger that can exchange heat between the first cooling liquid that cools the fuel cell and a different type of cold heat source, so that the fuel cell power generation device can be used for a variety of purposes.

This disclosure provides a fuel cell power generation device that can be used for a variety of purposes.

1 is a diagram showing an example of the configuration of a fuel cell power generation system including a fuel cell power generation device according to a first embodiment; 1 is a diagram showing in detail an example of the configuration of a fuel cell power generation device according to a first embodiment;

The following describes the embodiment.

Figure 1 is a diagram showing an example of the configuration of a fuel cell power generation system including a fuel cell power generation device of the first embodiment. The fuel cell power generation system 201 shown in Figure 1 is a system that supplies power generated by multiple FC (fuel cell) platforms connected in parallel to an external device 12 that is the power supply target. Specific examples of uses of the fuel cell power generation system 201 include stationary power generation systems, power generation systems for loading and unloading machines such as port cranes, and power generation systems for ships. Other uses include railways and construction machinery. Uses of the fuel cell power generation system 201 are not limited to these examples, and the fuel cell power generation system 201 may be applied to other applications.

The fuel cell power generation system 201 includes a fuel cell power generation device 101 and an auxiliary system 301.

The auxiliary system 301 is a peripheral system that includes multiple auxiliary devices connected to the fuel cell power generation device 101, which is the main device, and assists the operation of the fuel cell power generation device 101. FIG. 1 illustrates the multiple auxiliary devices as a control power supply 32, a purge system 30, a fuel system 18, an air supply system 19, an output line 17, a power conversion device 11, a DC/DC converter 13, a secondary battery 14, an exhaust system 31, and a cooler 15. Some or all of the multiple auxiliary devices may be built into the fuel cell power generation device 101, or may be unitized. The fuel cell power generation device 101 may include some or all of the multiple auxiliary devices inside the fuel cell power generation device 101, or outside the fuel cell power generation device 101.

The fuel cell power generation device 101 generates power to be supplied to an external device 12 using multiple FC platforms. The fuel cell power generation device 101 may be unitized. The fuel cell power generation device 101 includes multiple FC platforms (in this example, three FC platforms 1, 2, and 3) connected in parallel to an output line 17, and a control device 10 that controls the multiple FC platforms. The number of multiple FC platforms connected in parallel is not limited to three, and may be two, four, or more.

FC platforms 1, 2, and 3 each include an FC stack connected to a common output line 17 via an output point 16. The FC stack is an example of a fuel cell. FC platform 1 includes an FC stack 21, FC platform 2 includes an FC stack 22, and FC platform 3 includes an FC stack 23.

The FC stacks 21, 22, and 23 are devices that electrochemically convert the chemical energy of fuels such as hydrogen into electrical energy. The FC stacks 21, 22, and 23 generate electricity through an electrochemical reaction between hydrogen or hydrogen-rich gas supplied through a fuel system 18 including a fuel pipe and oxygen contained in air supplied from the outside through an air supply system 19 including an air pipe. The power generation state of the FC stacks 21, 22, and 23 (FC platforms 1, 2, and 3) is controlled by the control device 10. Exhaust gas generated by the electrochemical reaction of the FC stacks 21, 22, and 23 is discharged through an exhaust system 31 including an exhaust pipe. The FC stacks 21, 22, and 23 are cooled by a coolant supplied from a cooler 15 such as a radiator.

The FC stacks 21, 22, and 23 are, for example, polymer electrolyte fuel cells (PEFCs) and have a stack structure in which a large number of unit cells are stacked. The unit cell has a membrane-electrode assembly (MEA) in which both sides of a polymer electrolyte membrane for selectively transporting hydrogen ions are sandwiched between a pair of electrodes formed of a porous material, and a pair of separators that sandwich the MEA from both sides. Each of the pair of electrodes has a catalyst layer mainly composed of carbon powder that supports a platinum-based metal catalyst (electrode catalyst), for example, and a gas diffusion layer that is both breathable and electronically conductive.

The FC stacks 21, 22, and 23 are equipped with voltage sensors for detecting the voltages at their output terminals and current sensors for detecting the output currents from their output terminals. The control device 10 obtains the detection values of the voltages output from the FC stacks 21, 22, and 23 using the voltage sensors, and obtains the detection values of the currents output from the FC stacks 21, 22, and 23 using the current sensors. The control device 10 detects the output powers p1, p2, and p3 of the FC stacks 21, 22, and 23 using the detection values of the voltages and currents.

The power generated by the FC stacks 21, 22, 23 (FC platforms 1, 2, 3) in the fuel cell power generation device 101 is supplied to the external device 12 via the power conversion device 11.

The power conversion device 11 is a device that converts input power Pa into power Pc to be supplied to the external device 12. The power conversion device 11 is, for example, an inverter that converts DC power obtained by power generation in the FC stacks 21, 22, and 23 into AC power and supplies it to the external device 12. Specific examples of inverters include a power conditioner (PCS: Power Conditioning System) and a grid-connected inverter. When the external device 12 is a motor, the power conversion device 11 may be an inverter that drives the motor. The power conversion device 11 may be a converter that converts the voltage of the DC power obtained by power generation in the FC stacks 21, 22, and 23 into DC power of a different voltage and supplies it to the external device 12.

The DC power obtained by power generation in the FC stacks 21, 22, 23 may be charged to the secondary battery 14 connected to the output line 17 via the DC/DC converter 13. The power Pb discharged from the secondary battery 14 is supplied to the external device 12 via the power conversion device 11. The power Pb input (regenerated) from the external device 12 via the power conversion device 11 may be charged to the secondary battery 14. The charging or discharging of the secondary battery 14 is controlled by the DC/DC converter 13 that operates according to a drive control signal from the control device 10. The DC/DC converter 13 may not be required.

The secondary battery 14 is a chargeable and dischargeable battery. The secondary battery 14 may include a plurality of storage batteries 14 ₁ , ..., 14 _n (n is an integer of 2 or more) connected in series. Specific examples of the secondary battery 14 (the plurality of storage batteries 14 ₁ , ..., 14 _n ) include a lithium ion battery, a lithium ion capacitor, and an electric double layer capacitor.

The fuel system 18 may include a reforming device that reforms the hydrocarbon fuel supplied from the outside into hydrogen-rich gas. The reforming device outputs hydrogen-rich gas produced by a reforming reaction of the hydrocarbon fuel to the hydrogen pipe. The reforming device includes, for example, a desulfurizer that removes sulfur contained in the hydrocarbon fuel, a reformer that causes a reforming reaction of the desulfurized hydrocarbon fuel, and a CO remover that removes carbon monoxide (CO) generated during reforming.

Hydrocarbon fuels are not limited to city gas, but may also include methane gas, propane gas, digester gas derived from sewage sludge, etc., and biogas generated from food waste, etc.

The control device 10 is a controller that controls the operation of the FC platforms 1, 2, and 3. The control device 10 operates, for example, with power (e.g., 12-volt direct current power) supplied from a control power source 32. The control power source 32 is, for example, a control battery. The number of control devices 10 is not limited to one, and may be multiple. For example, a control device may be provided for each of the FC platforms 1, 2, and 3.

Figure 1 illustrates an example of a configuration in which a fuel cell power generation device 101 has a control power supply 32 common to FC platforms 1, 2, and 3. By sharing the power supply of FC platforms 1, 2, and 3 as a control power supply 32, the fuel cell power generation system 201 and the fuel cell power generation device 101 can be made smaller than in a configuration in which multiple control power supplies are provided.

The fuel cell power generation device 101 may be provided with individual control power supplies 32 for the FC platforms 1, 2, and 3. By providing multiple power supplies for the multiple FC platforms individually, even if some of the multiple control power supplies are unusable due to failure or maintenance, etc., the remaining power supplies can be used to continue operating some or all of the multiple FC platforms.

The functions of the control device 10 (the processing performed by the control device 10) are realized, for example, by a processor such as a CPU (Central Processing Unit) operating according to a program stored in memory. The functions of the control device 10 may also be realized by an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

2 is a diagram showing in detail an example of the configuration of the fuel cell power generation device 101 of the first embodiment. The fuel cell power generation device 101 includes, for example, a control device 10 and multiple FC platforms 1, 2, and 3. The FC platform 1 includes, for example, a fuel pipe 118, an air pipe 119, an air filter 33, an exhaust pipe 131, a first cooling system 36, a second cooling system 90, and an FC unit 51. The FC unit 51 includes an FC stack 21, a boost converter 42, a hydrogen pump 43, an air compressor 45, a water pump 44, an air inlet shutoff valve 77, and an exhaust air outlet shutoff valve 78, etc. The boost converter 42, the hydrogen pump 43, the air compressor 45, the water pump 44, the air inlet shutoff valve 77, and the exhaust air outlet shutoff valve 78, etc. are controlled by the control device 10. The FC platforms 2 and 3 have the same configuration and function as the FC platform 1, and are controlled by the control device 10 in the same manner as the FC platform 1. Therefore, the explanation of FC platforms 2 and 3 will be omitted, as the explanation of FC platform 1 will be used.

The FC stack 21 has a fuel electrode 71 and an air electrode 72. The FC stack 21 generates electricity by an electrochemical reaction between hydrogen or hydrogen-rich gas supplied to the fuel electrode 71 and oxygen contained in air supplied to the air electrode 72. The FC stack 21 is connected to the output line 17 via a boost converter 42. The boost converter 42 is a DC/DC converter that boosts the voltage output from the FC stack 21 and outputs the boosted DC power to the output line 17 via the output point 16. The output power of the multiple FC stacks 21, 22, and 23 in the multiple FC platforms 1, 2, and 3 is output to a common output line 17 via the corresponding boost converters 42.

Hydrogen is supplied to the fuel pipe 118 from a fuel system 18 commonly connected to the multiple FC platforms 1, 2, and 3. The fuel pipe 118 supplies hydrogen to the fuel electrode 71 via the inlet 75.

Air is supplied to the air pipe 119 from an air supply system 19 commonly connected to the multiple FC platforms 1, 2, and 3. The air pipe 119 supplies air to the air pole 72 of the FC stack 21 via an inlet 73. The air pipe 119 is not essential, and the air filter 33 may directly draw in air from the open parts of the FC platforms 1, 2, and 3.

The air filter 33 removes dust and impurities that may adversely affect the fuel cell from the air supplied via the air supply system 19 and air pipe 119, and supplies the air to the air compressor 45 via the air pipe 120. The air filter is also called an air cleaner.

The air compressor 45 compresses the air supplied through the air filter 33 and supplies it to the air electrode 72 of the FC stack 21. The oxygen-containing air compressed by the air compressor 45 is supplied to the air electrode 72 of the FC stack 21 via the inlet 73. The air inlet shutoff valve 77 shuts off the flow of air supplied from the air compressor 45 to the inlet 73 of the air electrode 72.

The exhaust pipe 131 discharges exhaust gas generated in the FC stack 21 to an exhaust system 31 commonly connected to multiple FC platforms 1, 2, and 3. The exhaust air outlet shutoff valve 78 shuts off the flow of off-gas discharged from the outlet 74 of the air electrode 72 of the FC stack 21 to the exhaust pipe 131.

The first cooling system 36 cools the FC stack 21 with a first cooling liquid such as cooling water. The first cooling system 36 has a first intermediate heat exchanger 34 that exchanges heat with a cold heat source 39 to cool the first cooling liquid. The water pump 44 circulates the first cooling liquid between the first intermediate heat exchanger 34 and the FC stack 21. The FC stack 21 is cooled by the first cooling liquid circulated by the water pump 44.

The first intermediate heat exchanger 34 is a heat exchanger capable of exchanging heat between the first cooling liquid that cools the FC stack 21 and a different type of cold heat source 39. The different types of cold heat sources 39 mean that the type of cold heat source 39 used does not matter. The first intermediate heat exchanger 34 can cool the first cooling liquid with any cold heat source 39, regardless of the type of cold heat source 39 used, thereby realizing a fuel cell power generation device 101 that can be used for various purposes such as those described above.

The first intermediate heat exchanger 34 has a heat dissipation section 40 through which the first cooling liquid circulating in the first cooling system 36 passes, and a heat receiving section 41 through which a heat medium that transfers heat between the cold heat source 39 passes. The heat medium supplied from the cold heat source 39 may be liquid or gas. The first cooling liquid is cooled by dissipating heat from the heat dissipation section 40 to the heat receiving section 41 in the first intermediate heat exchanger 34. A specific example of the first intermediate heat exchanger 34 is a plate heat exchanger, but the first intermediate heat exchanger 34 is not limited to this.

The multiple first intermediate heat exchangers 34 in the multiple FC platforms 1, 2, 3 may each exchange heat with a cold heat source 39 that is commonly connected to the multiple FC platforms 1, 2, 3. This allows the cold heat source 39 to be common between the multiple FC platforms 1, 2, 3, making it possible to reduce the size of the fuel cell power generation device 101. Note that the cold heat source 39 may be different between the multiple FC platforms 1, 2, 3.

The second cooling system 90 cools the air compressor 45 with a second cooling liquid such as cooling water. The second cooling system 90 has a second intermediate heat exchanger 92 that exchanges heat with a cold heat source 94 to cool the second cooling liquid. The pump 91 circulates the second cooling liquid between the second intermediate heat exchanger 92 and the air compressor 45. The air compressor 45 is cooled by the second cooling liquid circulated by the pump 91.

The second intermediate heat exchanger 92 is a heat exchanger capable of exchanging heat between the second cooling liquid that cools the air compressor 45 and a different type of cold heat source 94. The different types of cold heat sources 94 mean that the type of cold heat source 94 used does not matter. The second intermediate heat exchanger 92 can cool the second cooling liquid with any cold heat source 94, regardless of the type of cold heat source 94 used, thereby realizing a fuel cell power generation device 101 that can be used for various purposes such as those described above.

The second intermediate heat exchanger 92 has a heat dissipation section 95 through which the second cooling liquid circulating in the second cooling system 90 passes, and a heat receiving section 96 through which a heat medium passes to transfer heat between the cold heat source 94. The heat medium supplied from the cold heat source 94 may be liquid or gas. The second cooling liquid is cooled by dissipating heat from the heat dissipation section 95 to the heat receiving section 96 in the second intermediate heat exchanger 92. A specific example of the second intermediate heat exchanger 92 is a plate heat exchanger, but the second intermediate heat exchanger 92 is not limited to this.

The multiple second intermediate heat exchangers 92 in the multiple FC platforms 1, 2, 3 may each exchange heat with a cold heat source 94 that is commonly connected to the multiple FC platforms 1, 2, 3. This allows the cold heat source 94 to be common between the multiple FC platforms 1, 2, 3, making it possible to reduce the size of the fuel cell power generation device 101. Note that the cold heat source 94 may be different between the multiple FC platforms 1, 2, 3.

The cooler 15 (FIG. 1) is an example of the cold heat source 39 or the cold heat source 94. The cold heat source 39 or the cold heat source 94 is, for example, an air-cooled cooler, an open cooling tower, a closed cooling tower, cooling water in a factory, tap water, river water, seawater, the heat of vaporization of liquefied hydrogen, or the cold heat generated when compressed hydrogen expands.

The material of the heat receiving portion 41 of the first intermediate heat exchanger 34 is, for example, a low-elution metal with a relatively low elution rate of metal ions (for example, highly corrosion-resistant austenitic stainless steel (SUS316L)). If the heat medium in contact with the heat receiving portion 41 is seawater, for example, there is a risk that metal ions will be eluted from the heat receiving portion 41, depending on the material of the heat receiving portion 41. If the material of the heat receiving portion 41 is a low-elution metal as described above, the restrictions on the heat medium supplied from the cold heat source 39 are alleviated, and the options for the cold heat source 39 increase. As a result, a fuel cell power generation device 101 that can be used for various applications such as those described above is realized. The same applies to the material of the heat receiving portion 96 of the second intermediate heat exchanger 92.

In addition, by employing the first intermediate heat exchanger 34, the first coolant can dissipate heat without having to extend the path through which the first coolant circulates to the cold heat source 39 outside the FC platform. In other words, the path through which the first coolant circulates can be shortened, and the amount of expensive first coolant used to cool the fuel cell can be reduced. As a result, costs can be reduced. Similarly, by employing the second intermediate heat exchanger 92, the amount of second coolant used can be reduced, and costs can be reduced.

The cold heat source 94 from which the second intermediate heat exchanger 92 dissipates heat of the second cooling liquid may be the same as or different from the cold heat source 39 from which the first intermediate heat exchanger 34 dissipates heat of the first cooling liquid. If the cold heat source 94 and the cold heat source 39 are the same, the cold heat source is shared between the first intermediate heat exchanger 34 and the second intermediate heat exchanger 92, so that the fuel cell power generation device 101 can be made smaller.

The first cooling system 36 may include an ion exchanger 35 that removes ions from the first cooling liquid. By removing ions from the first cooling liquid, an increase in the electrical conductivity of the first cooling liquid inputted and outputted to the FC stack 21 is suppressed, thereby suppressing electrical interference between the FC stack 21 and the first cooling liquid.

In addition, by adopting the first intermediate heat exchanger 34, the dissolution of ions from the first cooling liquid on the first cooling system 36 side to the heat medium on the cold heat source 39 side is suppressed, thereby reducing the frequency of maintenance of the ion exchanger 35.

The first cooling system 36 may include a sensor 37 that measures the electrical conductivity of the first cooling liquid. By including the sensor 37, the electrical conductivity of the first cooling liquid can be managed. For example, if the sensor 37 detects that the electrical conductivity has started to increase, the user can know when to perform maintenance on the ion exchanger 35. In addition, by managing the electrical conductivity, the insulation between the DC PN (between the positive and negative) of the fuel cell can be maintained. If the electrical conductivity is measured to be equal to or greater than a first threshold value (e.g., 1 μS/cm), the sensor 37 or the control device 10 may issue an alarm so that the user can recognize it. If the electrical conductivity is measured to be equal to or greater than a second threshold value (e.g., 5 μS/cm) that is greater than the first threshold value, the control device 10 may stop the FC platform in which the electrical conductivity equal to or greater than the second threshold value is measured.

The first cooling system 36 may include a first tank 38 that absorbs expansion or contraction of the first cooling liquid caused by temperature changes. This suppresses expansion or contraction of the first coolant caused by temperature changes.

Similarly, the second cooling system 90 may include a second tank 93 that absorbs the expansion or contraction of the second cooling liquid caused by temperature changes. This suppresses the expansion or contraction of the second coolant caused by temperature changes.

The FC platform 1 may include a first gas-liquid separator 79 and a hydrogen pump 43. The first gas-liquid separator 79 separates hydrogen gas and wastewater from the first multiphase flow discharged from the outlet 76 of the fuel electrode 71. The hydrogen pump 43 circulates the hydrogen gas separated by the first gas-liquid separator 79 to the inlet 75 of the fuel electrode 71. This allows surplus hydrogen gas generated by power generation in the FC stack 21 to be reused for power generation in the FC stack 21.

The FC platform 1 may include a mixer 80. The exhaust pipe 131 discharges a second multiphase flow obtained by combining the wastewater separated by the first gas-liquid separator 79, hydrogen mixed in the wastewater, and exhaust air discharged from the outlet 74 of the air electrode 72 in the mixer 80. This allows the wastewater, hydrogen, and exhaust air to be discharged together.

The FC platform 1 may be provided with a second gas-liquid separator 81 that separates water and gas from the second multiphase flow. This allows the wastewater and exhaust gas to be separated and discharged. The wastewater or exhaust gas may be collected by a collector 82. This prevents the surrounding area from being polluted by the wastewater or exhaust gas.

The fuel cell power generation device 101 may include a purge system 30 that individually purges the multiple fuel pipes 118 in the multiple FC platforms 1, 2, and 3 with an inert gas such as nitrogen. The purge system 30 may switch the flow path with a valve so that the multiple fuel pipes 118 can be individually purged with the inert gas. This allows the deterioration of characteristics due to purging with the inert gas to be managed on a per-FC stack basis.

A portion of the output power p1 of the FC stack 21 is used as operating power for auxiliary equipment such as the air compressor 45 in the FC unit 51, and the surplus power is output as the output power P1 of the FC unit 51. The same applies to the output power p2 of the FC stack 22 and the output power p3 of the FC stack 23.

The control device 10 performs control to maintain the power supplied from the output line 17 to the outside at a substantially constant predetermined value. For example, the control device 10 controls the power generation of the FC stacks 21, 22, 23 (FC platforms 1, 2, 3) and the conversion operation of the DC/DC converter 13 so that the supply power Pa (=Po-Pb) output from the output line 17 to the power conversion device 11 is maintained at a constant target value. Po is the power at the output point 16. Po is equal to the sum of the output powers P1, P2, P3 of the FC platforms 1, 2, 3 (Po=P1+P2+P3). Pb is the power exchanged between the secondary battery 14 and the output line 17.

The control device 10 may control the power generation of the FC stacks 21, 22, and 23 and the conversion operation of the power conversion device 11 so that the power Pc output from the power conversion device 11 to the external device 12 follows a target value. Pa or Pc is an example of power supplied from the output line 17 to the outside.

The control device 10 may perform control (power fluctuation control) to change (more specifically, increase or decrease) the output power p1, p2, and p3 of the FC stacks 21, 22, and 23 while the supply power Pa from the output line 17 to the outside is maintained at a substantially constant value. The supply power Pa can be detected by a voltage sensor and a current sensor.

The control device 10, for example, increases or decreases the operating current (load current) of the boost converter 42 of the FC platform 1 to increase or decrease the load on the FC stack 21 and increase or decrease the output power p1. Similarly, the control device 10 increases or decreases the operating current (load current) of the boost converter 42 of the FC platform 2 to increase or decrease the load on the FC stack 22 and increase or decrease the output power p2. The control device 10 increases or decreases the operating current (load current) of the boost converter 42 of the FC platform 3 to increase or decrease the load on the FC stack 23 and increase or decrease the output power p3.

By the control device 10 performing the power fluctuation control as described above, the output powers p1, p2, and p3 of the multiple FC stacks 21, 22, and 23 are increased or decreased while the power supply Pa from the output line 17 to the outside is maintained at a substantially constant value. As a result, while a constant power supply from the output line 17 to the outside is ensured, the humidity distribution deviation in the cell surface of the multiple FC stacks 21, 22, and 23 is reduced compared to the case where the output powers p1, p2, and p3 are always controlled to be constant. By reducing the humidity distribution deviation in the cell surface, the increase in current density due to the decrease in effective reaction area is suppressed, and deterioration of the electrolyte membrane due to the increase in current density is suppressed. Therefore, by the control device 10 performing the power fluctuation control to increase or decrease the output powers p1, p2, and p3 while the supply power Pa is maintained at a substantially constant value, a substantially constant power supply is ensured and deterioration of the multiple FC stacks 21, 22, and 23 is suppressed. Suppressing deterioration of the multiple FC stacks 21, 22, and 23 contributes to improving the durability of the fuel cell power generation device 101 and the fuel cell power generation system 201.

The fuel cell power generation system 201 or the fuel cell power generation device 101 may include a plurality of switches (switches 61, 62, and 63 in this example) provided for each of the plurality of FC platforms. The switch 61 is a circuit breaker that switches between disconnection and connection of the power path between the FC stack 21 and the boost converter 42 and the output point 16 connected to the output line 17. The switch 62 is a circuit breaker that switches between disconnection and connection of the power path between the FC stack 22 and the boost converter (not shown) and the output point 16 connected to the output line 17. The switch 63 is a circuit breaker that switches between disconnection and connection of the power path between the FC stack 23 and the boost converter (not shown) and the output point 16 connected to the output line 17.

The control device 10 may separate some of the FC stacks 21, 22, and 23 from the other FC stacks by the switches 61, 62, or 63. With the FC stacks separated, the control device 10 may control the output power of the other FC stacks so that the power supply Pa is maintained at a substantially constant value. This makes it easy to replace the FC stacks while the power supply Pa is maintained at a substantially constant value. For example, with the FC stack 21 separated from the FC stacks 22 and 23 by the switch 61, the control device 10 may control the output power of the other FC stacks 22 and 23 so that the power supply Pa is maintained at a substantially constant value. The switches 61, 62, and 63 are automatically switched on and off by the control device 10, but may also be switched manually.

The fuel cell power generation system 101 may include shutoff valves for shutting off the piping and switches for shutting off the wiring so that some of the multiple FC platforms can be shut down and removed while the remaining FC platforms are in operation. The piping transmits liquids (coolant, drainage, etc.) or gases (air, hydrogen, exhaust gas, etc.), and the wiring transmits power and signals. Examples of shutoff valves for shutting off the piping include the air inlet shutoff valve 77 and the exhaust air outlet shutoff valve 78. Examples of switches for shutting off the wiring include switches 61, 62, and 63.

The fuel cell power generation system 101 may have a function for individually detecting ground faults in multiple FC platforms. For example, the control device 10 may use a switch 61, 62, or 63 to disconnect an FC platform among multiple FC platforms 1, 2, and 3 in which a drop in resistance to ground or a ground fault has been detected.

The number of the multiple storage batteries 14 ₁ , ..., 14 _n connected in series may be adjusted so that the output voltage of the secondary battery 14 is approximately equal to the output voltage at the output point 16. This makes it possible to eliminate the DC/DC converter 13 and reduce the size of the fuel cell power generation device 101.

Depending on the relationship between the power demand of the external device 12 and the fuel cell power generation system 101, multiple storage batteries 14 ₁ , ..., 14 _n may be connected in parallel to increase the capacity of the secondary battery 14. The number of parallel connections of the multiple storage batteries 14 ₁ , ..., 14 _n is preferably smaller than the number of the multiple FC platforms commonly connected to the output line 17. In this case, the fuel cell power generation system 101 can be made smaller than when storage batteries are individually connected to the output power lines of the multiple FC platforms.

In this way, according to this embodiment, the problem of decarbonizing power sources through hydrogen power generation can be solved in fields such as stationary generators, power sources for port loading and unloading machines (such as cranes), power sources for ships, power sources for railways, heavy construction machinery, and heavy civil engineering machinery. Hydrogen power generation can be done using hydrogen combustion or fuel cells, but the fuel cell type is generally more efficient. When applying fuel cells to multiple applications, it takes time and effort to develop each system. According to this embodiment, the problem of developing an inexpensive and highly efficient platform that can be used in common for various applications can be solved. More specifically, in order to apply it to various applications (stationary, crane, ship, railway, construction machinery, etc.), the common parts can be constructed as an FC platform, thereby reducing the system development resources (design, engineering, etc.) for each application. By using a platform common to each application, the mass production effect of the FC platform can be obtained, and the price can be reduced.

Furthermore, according to this embodiment, for the two cooling systems (first cooling system 36 and second cooling system 90), individual engineering of the cooling systems is not required depending on the system to which they are applied, the installation location, etc. More specifically, by installing one or both intermediate heat exchangers of the two cooling systems within the FC platform, individual engineering of the cooling systems is not required.

In addition, according to this embodiment, the parallelization of FC platforms can improve scalability and support high output. By constructing an FC platform that incorporates auxiliary equipment, multiple FC platforms can be easily parallelized, making it easier to improve scalability and support high output.

Furthermore, according to this embodiment, multiple FC platforms can be separated independently, facilitating handling such as transportation, which, for example, facilitates maintenance. For example, in the event of a system failure, the system downtime can be shortened by replacing each FC platform, improving the system's operating rate. In the event of a system failure, rather than repairing the system on-site, the FC platform can be returned to a factory and repaired there, reducing the cost of on-site repair. During the factory return period, a replacement FC platform can be replaced, improving the system's operating rate.

Although the embodiments have been described above, they are presented as examples, and the present invention is not limited to the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, modifications, etc. can be made without departing from the gist of the invention. These embodiments and their variations are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

For example, in FIG. 1, the point where the purge system 30 that supplies nitrogen merges with the fuel system 18 that supplies hydrogen is after the fuel system 18 branches off toward the FC stacks 21, 22, and 23, but it may be before the branching.

REFERENCE SIGNS LIST 1, 2, 3 FC platform 10 Control device 11 Power conversion device 12 External device 13 DC/DC converter 14 Secondary battery 14 ₁ , 14 _n battery 15 Cooler 16 Output point 17 Output line 18 Fuel system 19 Air supply system 21, 22, 23 FC stack 30 Purge system 31 Exhaust system 32 Control power supply 33 Air filter 34 First intermediate heat exchanger 35 Ion exchanger 36 First cooling system 37 Sensor 38 First tank 39 Cold source 40 Heat dissipation section 41 Heat receiving section 42 Boost converter 43 Hydrogen pump 44 Water pump 45 Air compressor 51 FC unit 61, 62, 63 Switch 71 Fuel electrode 72 Air electrode 73, 75 Inlet Reference Signs List 74, 76 Outlet 77 Air inlet shutoff valve 78 Exhaust air outlet shutoff valve 79 First gas-liquid separator 80 Mixer 81 Second gas-liquid separator 82 Recovery device 90 Second cooling system 91 Pump 92 Second intermediate heat exchanger 93 Second tank 94 Cold source 95 Heat dissipation section 96 Heat reception section 101 Fuel cell power generation device 118 Fuel pipe 119, 120 Air pipe 131 Exhaust pipe 201 Fuel cell power generation system 301 Auxiliary system

In a first aspect, a fuel cell power generator includes:
a fuel cell having an anode and an cathode;
a fuel pipe for supplying hydrogen to the fuel electrode;
an air compressor that compresses the supplied air and supplies it to the air electrode;
an exhaust pipe for discharging exhaust gas generated by the fuel cell;
The fuel cell is provided with a first intermediate heat exchanger capable of exchanging heat between a first cooling fluid that cools the fuel cell and a first cold heat source that is any one of air, liquid, and cold heat generated by the expansion of compressed hydrogen .

According to the first aspect, the fuel cell power generation device is provided with a first intermediate heat exchanger capable of exchanging heat between a first cooling liquid that cools the fuel cell and a first cold heat source which is any one of air, liquid, or cold heat generated by the expansion of compressed hydrogen , thereby making the fuel cell power generation device applicable to a variety of applications.

The first cooling system 36 may include a first tank 38 that absorbs expansion or contraction of the first cooling liquid caused by temperature changes. This suppresses expansion or contraction of the first cooling liquid caused by temperature changes.

Similarly, the second cooling system 90 may include a second tank 93 that absorbs expansion or contraction of the second cooling liquid caused by temperature changes, thereby suppressing expansion or contraction of the second cooling liquid caused by temperature changes.

The fuel cell power generation system 101 may include a purge system 30 that individually supplies an inert gas such as nitrogen to a plurality of fuel pipes 118 in a plurality of FC platforms 1, 2, and 3. The purge system 30 may switch flow paths using valves so that the plurality of fuel pipes 118 can be individually purged with the inert gas. This makes it possible to manage characteristic degradation caused by purging with the inert gas for each FC stack.

Claims (19)

a fuel cell having an anode and an cathode;
a fuel pipe for supplying hydrogen to the fuel electrode;
An air filter that removes impurities from the air;
an air compressor that compresses the air supplied through the air filter and supplies the compressed air to the air electrode;
an exhaust pipe for discharging exhaust gas generated by the fuel cell;
a first intermediate heat exchanger capable of exchanging heat between a first coolant for cooling the fuel cell and a different type of cold heat source, the first intermediate heat exchanger being provided with the fuel cell power generation apparatus. The fuel cell power generation device according to claim 1, further comprising a second intermediate heat exchanger capable of exchanging heat between a second cooling liquid for cooling the air compressor and a different type of cold heat source. The fuel cell power generation device according to claim 2, wherein the cold heat source from which the second intermediate heat exchanger dissipates heat of the second cooling liquid is the same as the cold heat source from which the first intermediate heat exchanger dissipates heat of the first cooling liquid. The fuel cell power generation device according to claim 1, further comprising an ion exchanger that removes ions from the first cooling liquid. The fuel cell power generation device according to claim 4, further comprising a sensor for measuring the electrical conductivity of the first cooling liquid. The fuel cell power generation device according to claim 1, further comprising a first tank that absorbs expansion or contraction of the first cooling liquid caused by temperature changes. a first gas-liquid separator for separating hydrogen gas from a first mixed-phase flow discharged from an outlet of the anode;
2. The fuel cell power generation system according to claim 1, further comprising: a hydrogen pump that circulates the hydrogen gas separated by the first gas-liquid separator to an inlet of the fuel electrode. The fuel cell power generation device according to claim 7, wherein the exhaust pipe discharges a second mixed-phase flow obtained by combining the wastewater separated by the first gas-liquid separator, hydrogen mixed in the wastewater, and exhaust air discharged from the outlet of the air electrode. The fuel cell power generation device according to claim 8, further comprising a second gas-liquid separator that separates water and gas from the second multiphase flow. Equipped with multiple fuel cell platforms,
each of the plurality of fuel cell platforms includes the fuel cell, the fuel pipe, the air filter, the air compressor, the exhaust pipe, and the first intermediate heat exchanger;
The output power of the fuel cells in the fuel cell platforms is output to a common output line.
10. A fuel cell power generation system according to any one of claims 1 to 9. The fuel cell power generation device according to claim 10, wherein the first intermediate heat exchangers in the fuel cell platforms exchange heat with a common cold source. The fuel cell power generation device according to claim 11, wherein the common cold source is an air-cooled cooler, an open cooling tower, a closed cooling tower, factory cooling water, tap water, river water, seawater, heat of vaporization of liquefied hydrogen, or cold generated when compressed hydrogen expands. The fuel cell power generation device according to claim 10, further comprising a control device that controls the output of each of the fuel cells so that the power supplied from the output line to the outside is maintained at a predetermined value. The fuel cell power generation device according to claim 13, wherein the control device separates some of the fuel cells from the other fuel cells and controls the output power of the other fuel cells so that the supply power is maintained at the predetermined value. The fuel cell power generation device according to claim 13, wherein each of the fuel cell platforms is provided with an individual control power supply. The fuel cell power generation device according to claim 13, comprising a control power supply common to the plurality of fuel cell platforms. a secondary battery connected to the output line;
11. The fuel cell power generation system according to claim 10, wherein the secondary battery includes a plurality of storage batteries connected in series. a plurality of storage batteries connected in parallel to the output line;
The fuel cell power plant of claim 10 , wherein the number of said plurality of storage batteries is less than the number of said plurality of fuel cell platforms. The fuel cell power generation system according to claim 10, further comprising a purge system for individually purging the inert gas into the fuel pipes in the fuel cell platforms.

Images