JP6770696B2 - Fuel cell systems, hybrid systems, aircraft and auxiliary power units onboard aircraft - Google Patents

Description

The present invention relates to fuel cell systems, hybrid systems, aircraft and auxiliary power units mounted on aircraft.

In recent years, a hybrid system that combines a fuel cell with a gas turbine for power generation used in an aircraft jet engine or an auxiliary power unit (APU) of an aircraft, a gas turbine for ground power generation, etc. has been proposed for practical use. Is under development.
For example, Non-Patent Document 1 discloses a hybrid aircraft engine in which a jet engine and a fuel cell are combined.
Further, Non-Patent Document 2 discloses a technique for raising the temperature of a fuel cell used in an APU of a hybrid system by a heat exchanger.

"Sky and Space No. 40" (January 2012, published by Japan Aerospace Exploration Agency, Research and Development Headquarters) See page 5 and Fig. 7. URL: http://www.iadf.or.jp/8361/LIBRARY/MEDIA/H22_dokojyoho/22-4.pdf See especially Fig. 3.

For example, in a solid oxide fuel cell (SOFC), the temperature required for operation is 900 ° C. to 1000 ° C., and it is preferable that the temperature is stable at a constant temperature from the viewpoint of power generation performance. However, the temperature and pressure of the working fluid supplied to the fuel cell from the outside change depending on the environment, and sometimes the working fluid changes suddenly. Taking the hybrid aircraft engine disclosed in Non-Patent Document 1 as an example, the temperature and pressure of the inlet air of a jet engine may fluctuate instantaneously depending on the situation, and this instantaneous fluctuation is supplied to the fuel cell as it is. It affects the working fluid, and the flow of the working fluid in the fuel cell greatly deviates from the design and deteriorates the performance, and may cause the destruction of the electrolyte in the cell and the like.

The heat exchanger disclosed in Non-Patent Document 2 compensates the temperature of the fuel cell to be constant, but has poor responsiveness to changes in temperature and pressure, and generally responds to sudden changes. It cannot follow up and the power generation performance deteriorates. In addition, if a heat exchanger is used to follow such a sudden change, the volume of the heat exchanger becomes very large and the weight becomes excessive, so that it is not suitable for an aircraft or an on-site power generation system, for example. Is.

In view of the above circumstances, an object of the present invention is to provide a fuel cell system capable of suppressing a decrease in power generation performance while suppressing an increase in volume and weight, and a hybrid system, an aircraft and an aircraft having such a fuel cell system. The purpose is to provide an auxiliary power unit to be mounted.

In order to achieve the above object, the fuel cell system according to one embodiment of the present invention includes a fuel cell and a compressor that supplies a working fluid controlled to a desired temperature to an inlet on the air electrode side of the fuel cell. To do.

In the fuel cell system according to one embodiment of the present invention, a working fluid controlled to a desired temperature is supplied to the inlet on the air electrode side of the fuel cell via a compressor, so that the fuel cell system is supplied from the outside. Even if the temperature and pressure of the supplied working fluid change suddenly, the deterioration of power generation performance can be suppressed. Here, the desired temperature means, for example, a constant temperature required for the operation of the fuel cell. Further, such a compressor has a sufficiently fast fluctuation response of inlet conditions and a sufficiently small capacity as compared with a heat exchanger, and can have the same or light weight. Therefore, the volume is sufficiently smaller than that of a heat exchanger or the like, the capacity of the heat exchanger can be made very small, or the heat exchanger can be eliminated, so that the power generation performance is lowered while suppressing the increase in volume. And suppresses damage to electrolytes, etc. caused by sudden fluctuations in inlet conditions.

In the fuel cell system according to one embodiment of the present invention, the compressor is a rotary type, and a turbine that rotationally drives the compressor by using a working fluid from an outlet on the air electrode side of the fuel cell as driving energy is further added. Equipped.

In the fuel cell system according to one embodiment of the present invention, the working fluid supplied to the fuel cell reacts with hydrogen or the like by the fuel cell to generate electricity. Since the temperature of the working fluid rises further due to the heat generated in the chemical reaction process, the working fluid is expanded by a turbine and a turbo mechanism driven by it is adopted to suppress the power supply from the outside. It enables operation, enhances the efficiency of the system, and more efficiently suppresses the increase in volume while suppressing the deterioration of power generation performance.

The fuel cell system according to one embodiment of the present invention further includes a driving means in which the compressor and the turbine are connected by a common central shaft, and the central shaft is rotationally driven.
By providing the drive means in this way, when the power is insufficient in the turbo mechanism or the like, it is possible to make up for it by driving the drive means.
The fuel cell system according to one embodiment of the present invention further includes a combustor that burns a working fluid from an outlet on the air electrode side of the fuel cell.

In the fuel cell system according to one embodiment of the present invention, the remaining hydrogen or the like generated by the fuel cell is burned by the combustor to increase the generated power of the turbine or the like, and the power generation performance while suppressing the increase in volume more efficiently. Can be suppressed.
The fuel cell system according to one embodiment of the present invention further includes at least one of a heat exchanger or a heater for heating the working fluid supplied to the compressor.
By providing the heat exchanger and the heater in this way, when the temperature rise is insufficient in the compressor or the like, it can be compensated by the heat exchanger or the heater.
In the fuel cell system according to one embodiment of the present invention, the fuel cell is a solid oxide fuel cell.

Solid oxide fuel cells (SOFCs) are difficult to manufacture to withstand sudden pressure fluctuations. In the fuel cell system according to one embodiment of the present invention, by providing a compressor in front of the fuel cell, it is possible to absorb pressure fluctuations of the working fluid supplied to the fuel cell system from the outside, and a solid oxide fuel cell can be provided. It can be protected from sudden changes in the environment.
The hybrid system according to one embodiment of the present invention includes a heat engine, a first flow path, and a fuel cell system.

The heat engine drives a first compressor that compresses the gas, a first combustor that burns fuel with the gas compressed by the first compressor, and a combustion gas from the first combustor. As a source, it has a first turbine for driving the first compressor. The first flow path is for taking out a part of the gas supplied to the first combustor to the outside of the heat engine. The fuel cell system introduces the gas as a working fluid of the fuel cell through the fuel cell and the first flow path, and brings the working fluid to a desired temperature at an introduction port on the air electrode side of the fuel cell. It has a second compressor that is controlled and supplied.

In the hybrid system according to one embodiment of the present invention, since the working fluid controlled to a desired temperature is supplied to the inlet on the air electrode side of the fuel cell via the second compressor, it is supplied from the heat engine side. Even if the temperature and pressure of the working fluid are suddenly changed, it is possible to suppress the deterioration of the power generation characteristics and prevent damage to the electrolyte and the like. Further, since the volume of such a second compressor is sufficiently smaller than that of a heat exchanger or the like, it is possible to suppress an increase in volume, suppress a decrease in power generation characteristics, and suppress damage to an electrolyte or the like. Furthermore, since the fuel cell system having the second compressor is independent of the heat engine, it is not necessary to incorporate the second compressor or the like on the heat engine side, and it is independent of the operation of the heat engine of the main body. Since the operating environment of the fuel cell, which is a subsystem, can be controlled, the fuel cell system can be used in combination with various heat engines.

In the hybrid system according to one embodiment of the present invention, the second compressor is a rotary type, and the fuel cell system uses the working fluid from the outlet on the air electrode side of the fuel cell as driving energy. It further has a second turbine that rotationally drives the two compressors.

In the hybrid system according to one embodiment of the present invention, the working fluid supplied to the fuel cell reacts with hydrogen or the like by the fuel cell to generate electricity. Since the temperature of the working fluid rises further due to the heat generated in the chemical reaction process, the efficiency of the second compressor is improved by expanding this working fluid in the second turbine and adopting a turbo mechanism driven by it. It is possible to suppress the decrease in power generation performance while suppressing the increase in volume more efficiently.

In the hybrid system according to one embodiment of the present invention, the second compressor and the second turbine are connected by a common central shaft, and the fuel cell system is a drive means for rotationally driving the central shaft. Further has.
By providing the drive means in this way, when the power is insufficient in the turbo mechanism or the like, it is possible to make up for it by driving the drive means.

In the hybrid system according to one embodiment of the present invention, the fuel cell system further includes a second combustor that burns a working fluid from an outlet on the air electrode side of the fuel cell.

In the hybrid system according to one embodiment of the present invention, the remaining hydrogen or the like generated by the fuel cell is burned by the second combustor to improve the efficiency of the second turbine or the like and suppress the power supply from the outside. It is possible to operate the compressor, improve the efficiency of the system, and more efficiently suppress the increase in volume while suppressing the decrease in power generation performance.

The hybrid system according to one embodiment of the present invention further includes a second flow path for supplying the working fluid discharged from the fuel cell system to the first combustor of the heat engine.

The working fluid discharged from the fuel cell system may be discharged to the outside as it is, but by supplying the working fluid discharged from the fuel cell system to the first combustor of the heat engine in this way, the fuel cell The remaining hydrogen, etc. generated in the above can be reused.
The hybrid system according to one embodiment of the present invention further includes at least one of a heat exchanger or a heater for heating the working fluid supplied to the second compressor.
By providing the heater and the heat exchanger in this way, if the temperature rise is insufficient in the second compressor or the like, it can be compensated by the heater or the heat exchanger.
In the hybrid system according to one embodiment of the present invention, the fuel cell is a solid oxide fuel cell.

In the hybrid system according to one embodiment of the present invention, by providing a compressor in front of the fuel cell, it is possible to absorb the pressure fluctuation of the working fluid supplied from the heat engine, and the solid oxide fuel cell has a sudden environmental change. Can be protected from.
The aircraft according to one embodiment of the present invention is equipped with the above hybrid system, and the heat engine is a jet engine.

In the aircraft according to one embodiment of the present invention, it is possible to suppress a decrease in power generation performance even if the temperature or pressure of the working fluid, which is a part of the gas supplied from the jet engine, suddenly changes. In addition, it is possible to suppress a decrease in power generation performance while suppressing an increase in volume. Further, since the fuel cell system is independent of the jet engine, it is not necessary to incorporate a second compressor or the like into the jet engine, and the fuel cell system can be used in combination with various jet engines.
The auxiliary power unit mounted on the aircraft according to the embodiment of the present invention includes a generator driven by the first turbine.

In the auxiliary power unit mounted on the aircraft according to one embodiment of the present invention, it is possible to suppress a decrease in power generation performance even if the temperature or pressure of the working fluid supplied from the heat engine changes suddenly. Moreover, the increase in volume can be suppressed. Furthermore, since the fuel cell system having a compressor is independent of the heat engine, it is not necessary to incorporate a second compressor or the like into the heat engine, and the fuel cell system can be used in combination with various heat engines. It will be possible.

In the present invention, it is possible to suppress a decrease in power generation performance while suppressing an increase in volume and weight.

It is the schematic of the aircraft which concerns on one Embodiment of this invention. It is a block diagram which shows the structure of the jet engine / fuel cell hybrid system mounted on the aircraft shown in FIG. The performance characteristic map of a general compressor is shown. It is the schematic which shows the structure of the fuel cell shown in FIG. In a jet engine / fuel cell hybrid system that does not adopt the main configuration according to the present invention, a state in which a temporary temperature fluctuation at the jet engine inlet propagates inside is shown. In the jet engine / fuel cell hybrid system adopting the main configuration according to the present invention, it is shown how the temporary temperature fluctuation at the jet engine inlet propagates inside. It is a graph which shows the temperature fluctuation in the main part of FIGS. 5 and 6. It is a graph which shows the voltage fluctuation of the fuel cell of FIG. It is a block diagram which shows the structure of the jet engine / fuel cell hybrid system which concerns on other embodiment of this invention. It is a block diagram which shows the structure of the auxiliary power unit (APU: Auxiliary Power Unit) of the aircraft which concerns on still another Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic view of an aircraft to which the present invention is applied.

As shown in FIG. 1, the aircraft 10 is composed of a fuselage 11, a main wing 12, a vertical tail 13, a horizontal stabilizer 14, and the like. Engine nacelles 15 are arranged on the left and right main wings 12, respectively. Each engine nacelle 15 is equipped with a jet engine, which is a component of a jet engine / fuel cell hybrid system described later.
[Jet engine / fuel cell hybrid system]
FIG. 2 is a block diagram showing a configuration of a jet engine / fuel cell hybrid system according to an embodiment.

As shown in FIG. 2, the jet engine / fuel cell hybrid system 20 is mounted on the aircraft 10 shown in FIG. 1, and includes a jet engine 21, a fuel cell system 22, and a flow path 23.

The jet engine 21 is an aviation that takes in air from the outside, compresses it with a compressor, burns oxygen and fuel in a combustor to generate a jet, and uses the reaction caused by the jet for propulsion. It is called a jet engine. Further, the jet engine according to the present invention includes a case where the jet engine is generated, a turbine is used to generate a rotational force, and the jet engine is converted into lift of a propeller or a fan and used as a propulsive force.

In the jet engine / fuel cell hybrid system 20, a part of the gas compressed as described above by the jet engine 21 is taken out to the outside, and the taken out gas is supplied to the fuel cell system 22 via the flow path 23. In the fuel cell system 22, the supplied gas is used as a working fluid.

The fuel cell system 22 is a system that generates electricity by a fuel cell, and the electric power generated by the fuel cell system 22 can be used, for example, as a part or all of the power source of the aircraft 10. By combining the electric power generated by the rotational force of the shaft of the jet engine 21 and the electric power generated by the fuel cell system 22 as the power source for the aircraft 10, the power generation performance can be improved and the electric power can be improved. It is effective in that the generated power can be set independently of the main jet engine 21.
<Jet engine>

The jet engine 21 is housed in the engine nacelle 15 shown in FIG. 1, and has a configuration in which a two-axis turbofan engine 26 is arranged between an air intake port 24 and a main nozzle 25. In the present embodiment, an example is shown in which the twin-screw turbofan engine 26 is used as the jet engine 21, but the present invention is not limited to this, as long as it produces a jet by air combustion. ..
The air intake port 24 has a circular opening on the front surface of the engine nacelle 15 and takes in outside air from the opening to the inside.

The two-shaft turbofan engine 26 includes a fan 27, a high-pressure compressor 28, a duct 30, a mixer 31, a combustor 32, a high-pressure turbine 33, and a low-pressure turbine 34 in the order closer to the air intake port 24. Are arranged and configured.
The fan 27 and the low pressure turbine 34 are connected by a common first shaft 35.

The fan 27 has a fan hub 36 that feeds gas to the high-pressure compressor 28 in the inner peripheral region, and a fan tip 38 that feeds gas to the bypass nozzle 37 in the outer peripheral region.

The high-pressure compressor 28 and the high-pressure turbine 33 are connected by a common second shaft 39.
The gas compressed by the high-pressure compressor 28 is sent to the combustor 32 via the duct 30 and the mixer 31.

The combustor 32 mixes and burns the supplied gas and fuel. The combustion gas is sent to the main nozzle 25 via the high pressure turbine 33 and the low pressure turbine 34. The combustion gas sent to the main nozzle 25 is ejected from the rear of the engine nacelle 15 as a jet along with the gas sent to the bypass nozzle 37, and is used as a propulsive force. Further, the high-pressure turbine 33 serves as a power source for rotating the high-pressure compressor 28, and the low-pressure turbine 34 serves as a power source for rotating the fan 27.
<Flow path>

The duct 30 is provided with, for example, a hole (not shown) for sending a part of the gas sent from the high-pressure compressor 28 to the outside on the outer periphery thereof, and one end of the flow path 23 is connected to this hole. There is. The other end of the flow path 23 is connected to the fuel cell system 22, and a part of the gas sent from the high-pressure compressor 28 is supplied to the fuel cell system 22 as a working fluid through the flow path 23.

A heat exchanger 40 is inserted in the flow path 23. The heat exchanger 40 takes out a part of the gas ejected from the main nozzle 25, for example, and raises the temperature of the working fluid in the flow path 23. A heater may be used instead of the heat exchanger 40, or a heater may be used in combination with the heat exchanger 40. Further, the heat exchanger and the heater may be configured to raise the temperature of the fuel cell itself, which will be described later, regardless of the location as long as the temperature of the working fluid can be raised, instead of the flow path 23.
<Fuel cell system>

As shown in FIG. 2, the fuel cell system 22 includes a compressor 41, a fuel cell 42, a turbine 43, a shaft 44, and a motor 45 as a driving means. The motor 45 may have a function as a generator.

The fuel cell system 22 is arranged, for example, in the immediate vicinity of the jet engine 21 in the engine nacelle 15 of the aircraft 10 and in a place where the air flow is not blocked as much as possible. Further, although the engine nacelle 15 may be separated from the jet engine 21 and arranged in a place, a vacant place in the fuselage 11 so as to shorten the flow path 23 as much as possible is preferable. For example, it may be arranged near the attachment position of the main wing 12 on the fuselage 11.

The compressor 41 is a rotary type, and by heating and pressurizing the working fluid supplied from the flow path 23, the working fluid controlled to a desired temperature and pressure is supplied to the introduction port on the air electrode side of the fuel cell 42. To do. For example, the compressor 41 instantly heats and applies the working fluid supplied from the flow path 23 to a desired temperature and pressure of about 600 ° C. to 900 ° C. to 1000 ° C. and 20 atm to 30 atm to 100 atm. Press. Therefore, the compressor 41 can suppress the instantaneous fluctuation of the inlet air of the jet engine 21 so as not to directly affect the inlet of the fuel cell 42.

As a mechanism for controlling the working fluid to a desired temperature and pressure, the following method can be adopted.
Here, a performance characteristic map of a general compressor is shown in FIG.

In FIG. 3, the horizontal axis is the corrected flow rate of air, the vertical axis is the pressure ratio at the inlet and outlet of the compressor, and a line with a constant corrected rotation speed is written in the figure (maximum is 100%). In addition, the contour lines in the figure represent lines with constant heat insulation efficiency.

The pressure at the outlet of the compressor 41 is determined by the pressure at the inlet of the compressor 41 and the pressure ratio, and the temperature at the outlet of the compressor 41 is determined by the temperature at the inlet of the compressor 41, the pressure ratio and the heat insulation efficiency. Both the pressure ratio and the adiabatic efficiency are determined by the modified rotation speed and the modified flow rate. The modified rotation speed and the modified flow rate are defined as follows.
Nc = N / √θ
Wc = (W√θ) / σ
θ = T / Ts
σ = P / Ps

Here, Nc: corrected rotation speed, N: rotation speed, θ: temperature ratio, Wc: corrected flow rate, W: flow rate, δ: pressure ratio, T: inlet temperature, Ts: standard atmospheric temperature (288.15K), P. : Inlet pressure, Ps: Standard atmospheric pressure (101.3 kPa).
Therefore, the temperature and pressure at the outlet of the compressor 41 can be controlled to a desired temperature and pressure by controlling the correction rotation speed and the correction flow rate of the compressor 41.

In order to control the modified rotation speed, the driving force of the motor 45 and the load of the power generation load when the motor 45 is provided with the power generation function are controlled, and the fuel amount of the combustor 61 described later is controlled. This can be achieved by controlling the output of the turbine 43 or by using both.

The corrected flow rate can be controlled by providing a flow control valve inside the fuel cell system 22 or between the fuel cell system 22 and the jet engine 21 and controlling the flow control valve. The place where the flow control valve is provided is preferably on the flow path 23 where the temperature is relatively low, for example.
As described above, the working fluid can be controlled to a desired temperature and pressure on the fuel cell system 22 side independently of the jet engine 21 side.

As the fuel cell 42, a solid oxide fuel cell (SOFC) is typically used. The temperature required to operate an SOFC is 900 ° C to 1000 ° C, and it is preferable that the SOFC is stable at a constant temperature from the viewpoint of power generation performance, and generally the strength against sudden pressure fluctuations is insufficient. Is. However, in the present embodiment, since the compressor 41 suppresses the instantaneous fluctuation of the inlet air of the jet engine 21 so as not to directly affect the inlet of the fuel cell 42, the deterioration of the power generation performance is suppressed. It can withstand sudden pressure fluctuations. The fuel cell 42 may be of another type such as a molten carbonate fuel cell (MCFC) in addition to the solid oxide fuel cell (SOFC).

FIG. 4 is a schematic view showing the configuration of the fuel cell 42. As shown in FIG. 4, in the fuel cell 42, the electrolyte 47 that divides the room into two is arranged in the container 46, and the anode 48 and the air electrode (cathode) 49 are arranged on both sides of the electrolyte 47, respectively. A fuel inlet 50 and an outlet 51 are provided on the anode 48 side of the container 46, and a working fluid inlet 52 and an outlet 53 are provided on the air electrode 49 side of the container 46. The working fluid from the compressor 41 is supplied to the introduction port 52 on the air electrode 49 side of the fuel cell 42, reacts with hydrogen or the like in the room, and generates electricity. Since the temperature of the working fluid rises further due to the heat generated in the chemical reaction process, the working fluid is led out to the turbine 43 side from the outlet 53, expanded by the turbine 43, and returned to the jet engine 21 side or released to the outside as described later. To do.
The turbine 43 is rotationally driven by the working fluid discharged from the outlet 53 on the air electrode 49 side of the fuel cell 42.

As shown in FIG. 2, the compressor 41, the turbine 43, and the motor 45 are connected by a common shaft 44. The turbine 43 serves as a power source for rotating the compressor 41. The motor 45 also serves as a power source for rotating the compressor 41. The motor 45 controls the compressor 41 so that the required rotation speed can be obtained when the power for rotationally driving the compressor 41 is insufficient in the turbine 43. As a result, the pressure and temperature of the working fluid supplied from the compressor 41 to the fuel cell 42 can be secured.

Here, the motor 45 can use electricity from a capacitor (not shown). For example, the surplus electricity generated by the fuel cell 42 is stored in the capacitor, and the use and charging of electricity from such a capacitor causes the turbine 43 to power the compressor 41 as the temperature of the fuel cell 42 rises. It depends on the situation of being able to supply and cover the necessary boosting and temperature rise. Combustion of excess hydrogen (by a combustor described later) and power extraction from the turbine 43 are related to the possibility of suppressing the amount of electric energy used by the motor 45.

It should be noted that other driving means may be used instead of the motor 45. Further, when the turbine 43 is sufficient as the power source of the compressor 41, it is not necessary to use a driving means such as a motor 45.

The working fluid expanded by the turbine 43 is returned to the jet engine 21 side via the flow path 54. For example, one end of the flow path 54 is connected to the discharge port of the turbine 43, and the other end of the flow path 54 is connected to a hole (not shown) provided in the duct 30, and the working fluid expanded by the turbine 43. Is returned to the duct 30 of the jet engine 21. Of course, the working fluid expanded by the turbine 43 may be discharged to the outside.
<Action / effect of jet engine / fuel cell hybrid system>

As shown in FIG. 2, in the jet engine / fuel cell hybrid system 20, the external air taken in from the air intake port 24 passes through the fan 27 and is compressed by the high pressure compressor 28. The gas compressed by the high-pressure compressor 28 is sent to the combustor 32 via the duct 30 and the mixer 31, and is mixed with the fuel by the combustor 32 and burned. The combustion gas is sent to the main nozzle 25 via the high-pressure turbine 33 and the low-pressure turbine 34, and together with the gas sent to the bypass nozzle 37, is ejected from the rear of the engine nacelle 15 as a jet and used as a propulsive force.

Further, a part of the gas sent from the high-pressure compressor 28 is supplied to the fuel cell system 22 as a working fluid via the flow path 23. The supplied working fluid is heated and pressurized by the compressor 41 to be controlled to a desired constant temperature, and is supplied to the introduction port on the air electrode side of the fuel cell 42. The working fluid discharged from the outlet 53 on the air electrode 49 side of the fuel cell 42 is expanded by the turbine 43 and returned to the duct 30 on the jet engine 21 side via the flow path 54.

Here, FIG. 5 shows how a temporary temperature fluctuation at the jet engine inlet propagates inside in a jet engine / fuel cell hybrid system that does not adopt the main configuration according to the present invention. On the other hand, FIG. 6 shows how the temporary temperature fluctuation at the jet engine inlet propagates inside in the jet engine / fuel cell hybrid system adopting the main configuration according to the present invention.

In the system shown in FIG. 5, a compressor is not inserted in the inlet of the fuel cell 42 in the fuel cell system 22, and the air (working fluid) from the duct 30 is directly passed through the flow path 23 to the fuel cell 42. It is introduced from the introduction port of. Further, a heat exchanger 100 that raises the temperature of the fuel cell 42 by using a part of the fuel gas from the main nozzle 25 is arranged adjacent to the fuel cell 42. A combustor 61 is arranged at the outlet of the fuel cell 42.

As shown in FIG. 6, when the temperature of the air at the jet engine inlet fluctuates as shown in the waveform A due to the acceleration / deceleration operation of the rotating machine of the jet engine, the external air taken in from the air intake port 24 causes the fan 27 to move. The temperature of the high-pressure compressor 28 also fluctuates in the same manner as the waveform A, and the temperature of the duct 30 also fluctuates in the same manner as the waveform A. Then, a part of the gas sent from the high-pressure compressor 28 is supplied to the fuel cell system 22 as a working fluid via the flow path 23, but the temperature fluctuates in substantially the same manner as the waveform A. The pressure fluctuation is similar to this.

On the other hand, in the system according to the present invention shown in FIG. 5, the temperature of the external air taken in from the air intake port 24 is almost the same as that of the waveform A even in the high pressure compressor 28 via the fan 27. Further, the temperature of the duct 30 also fluctuates in the same manner as the waveform A, but since the compressor 41 is inserted in the inlet of the fuel cell 42 in the fuel cell system 22, the inlet air of the jet engine 21 is inserted. The instantaneous fluctuation of is suppressed by this compressor 41, and the fluctuation becomes extremely small as shown in the waveform B of FIG. The pressure fluctuation is similar to this.

FIG. 6 shows the temperature change of the air at the air intake port 24 and the temperature change of the air at the outlet of the high pressure compressor 28 (common to the systems of FIGS. 5 and 6). Then, here, the temperature of the air at the air intake port 24 was rapidly changed between 5 and 10 s. Then, the temperature at the outlet of the high-pressure compressor 28 also fluctuates abruptly.

FIG. 8 shows the system shown in FIG. 5, that is, the air (working fluid) from the duct 30 is introduced through the flow path 23 without inserting a compressor into the inlet of the fuel cell 42 in the fuel cell system 22. It shows the temporal fluctuation of the cell voltage of the fuel cell 42 when the fuel cell 42 is introduced as it is from the inlet of the fuel cell 42.

In the system shown in FIG. 5, when the temperature at the outlet of the high-pressure compressor 28 fluctuates abruptly, a part of the gas sent from the high-pressure compressor 28 is supplied to the fuel cell 42 as a working fluid as it is through the flow path 23. Therefore, the temperature of the working fluid also fluctuates rapidly. As a result, as shown in FIG. 8, the cell voltage of the fuel cell 42 fluctuates in response to a sudden fluctuation in temperature, and its performance depends on the temperature at which it takes time to suppress the fluctuation in order for the voltage to recover. Since the response is slow, the voltage gradually returns to the original value. On the other hand, in the system according to the present invention shown in FIG. 6, even if the temperature at the outlet of the high-pressure compressor 28 fluctuates suddenly, the compressor 41 inserted in the inlet of the fuel cell 42 causes the sudden fluctuation. variation is suppressed, since the working fluid in which the changes is suppressed is supplied to the fuel cell 42, there is no possibility that the cell voltage of the fuel cell 42 is almost varied.

The same applies to pressure fluctuations. That is, in the system shown in FIG. 5, when the pressure at the outlet of the high-pressure compressor 28 suddenly fluctuates, the fluctuation directly affects the fuel cell 42. As described above, it is difficult to manufacture the fuel cell 42 so as to withstand sudden pressure fluctuations, which has been a problem when constructing a system. On the other hand, in the system according to the present invention shown in FIG. 6, even if the pressure at the outlet of the high-pressure compressor 28 fluctuates suddenly, the compressor 41 inserted in the introduction port of the fuel cell 42 causes the sudden fluctuation. Since the fluctuation is suppressed and the working fluid in which the fluctuation is suppressed is supplied to the fuel cell 42, it is possible to construct a system that can withstand a sudden pressure fluctuation.

Furthermore, in the system shown in FIG. 5, the temperature of the working fluid supplied from the outlet of the high-pressure compressor 28 to the fuel cell 42 via the flow path 23 has not reached the temperature required for the operation of the fuel cell 42. Since there are many cases, the temperature of the fuel cell 42 is raised by the heat exchanger 100. However, the heat exchanger 100 has a very large volume due to its structure, and is not suitable as a system mounted on an aircraft or the like. On the other hand, in the system according to the embodiment of the present invention, it is assumed that such a compressor 41 has a sufficiently small volume as compared with the heat exchanger 100 and the like, and is equipped with the heat exchanger 100 (40). However, since the capacity can be made very small or the heat exchanger itself can be eliminated, it is possible to suppress an increase in volume and a decrease in power generation performance.

Further, it is conceivable to provide a compressor for compressing the gas supplied to the fuel cell on the jet engine 21 side, but in that case, the control depends on the operation of the jet engine 21 side, and the desired temperature and pressure are provided. The working fluid cannot be supplied to the fuel cell. On the other hand, in the system according to the present embodiment, the fuel cell system 22 having the compressor 41 which is a subsystem controls the working fluid to a desired temperature and pressure independently of the jet engine 21 side which is the main body. Since it is possible to do so, it is not necessary to incorporate a compressor or the like into the jet engine 21 side, and the operating environment of the fuel cell 42 on the subsystem side can be controlled independently of the operation of the jet engine 21 of the main body. Can be used in combination with various jet engines.
[Other forms of jet engine / fuel cell hybrid system]
FIG. 9 is a block diagram showing a configuration of a jet engine / fuel cell hybrid system according to another embodiment of the present invention.

As shown in FIG. 9, this jet engine / fuel cell hybrid system 220 burns in the subsequent stage of the fuel cell 42 in the fuel cell system 222, unlike the system according to the embodiment in which the configuration of the fuel cell system 222 is described first. A vessel 61 is arranged, and the fuel discharged from the outlet of the anode of the fuel cell 42 is also configured to be burned by the combustor 61 in the subsequent stage.

As shown in FIG. 9, the fuel cell system 222 includes a compressor 41, a fuel cell 42, a combustor 61, a turbine 43, a shaft 44, and a motor 45. The same elements as those shown in FIG. 2 are designated by the same reference numerals.

Here, the compressor 41 heats and pressurizes the working fluid supplied from the flow path 23 to supply the working fluid controlled to a desired temperature and pressure to the introduction port on the air electrode side of the fuel cell 42. Therefore, the compressor 41 can suppress the instantaneous fluctuation of the inlet air of the jet engine 21 so as not to directly affect the inlet of the fuel cell 42.

The fuel cell 42 typically has the configuration shown in FIG. 4, and a solid oxide fuel cell (SOFC) is used. The working fluid from the compressor 41 is supplied to the introduction port 52 on the air electrode 49 side of the fuel cell 42, reacts with hydrogen or the like in the room, and generates electricity. The temperature of the working fluid rises further due to the heat generated during the chemical reaction process. By introducing a combustion gas discharged from the working fluid and the anode side of the outlet port 51 which is discharged from the outlet 53 of the air electrode 49 side to the combustor 61 by burning inflated, further diverted to the turbine 43 side, the turbine It is further expanded by 43 and returned to the duct 30 of the jet engine 21 via the flow path 54. The working fluid expanded by the turbine 43 may be discharged to the outside. Further, the combustion gas discharged from the outlet 51 on the anode side may be discharged without being introduced into the combustor 61.

By arranging the combustor 61 at the rear stage of the fuel cell 42 in this way, the output of the turbine 43 is increased, and thereby the output of the compressor 41 is improved, so that the heat exchanger 40 can be made very small or heat exchange. It is possible to eliminate the need for the vessel 40 itself.
[Auxiliary power unit of aircraft (APU: Auxiliary Power Unit)]
FIG. 10 is a block diagram showing a configuration of an APU mounted on an aircraft according to still another embodiment of the present invention.

As shown in FIG. 10, the APU 120 mounted on this aircraft is mounted near, for example, the tail wings 13 and 14 of the fuselage 11 of the aircraft 10 shown in FIG. 1, and includes a power generation system 121 and a fuel cell system. It includes 122 and a flow path 123.

In the APU 120, a part of the gas compressed from the power generation system 121 is taken out to the outside, and the taken out gas is supplied to the fuel cell system 122 via the flow path 23. The fuel cell system 122 uses the supplied gas as the working fluid.
The electric power generated by the APU 120 is used as a power source for the aircraft 10.
The power generation system 121 includes a generator 110, a compressor 128, a duct 130, a mixer 131, a combustor 132, and a turbine 133.
The generator 110, the compressor 128, and the turbine 133 are connected by a common shaft 139.
Air is introduced into the compressor 128 from the outside, and the gas compressed by the compressor 128 is sent to the combustor 132 via the duct 130 and the mixer 131.
The combustor 132 mixes and burns the supplied gas and fuel. The combustion gas is discharged to the outside via the high-pressure turbine 133.
The turbine 133 serves as a power source for rotating the generator 110 and the compressor 128, and power is generated by rotating the generator 110.
The fuel cell system 122 includes a compressor 141, a fuel cell 142, a turbine 143, and a shaft 144.

The compressor 141 heats and pressurizes the working fluid supplied from the flow path 123 to supply the working fluid controlled to a desired temperature and pressure to the introduction port on the air electrode side of the fuel cell 142.

As the fuel cell 142, a solid oxide fuel cell (SOFC) is typically used. The fuel cell 142 may be of another type such as a molten carbonate fuel cell (MCFC) in addition to the solid oxide fuel cell (SOFC).
The configuration of the fuel cell 142 is, for example, the same as that shown in FIG.

The working fluid from the compressor 141 is supplied to the inlet on the air electrode side of the fuel cell 142, reacts with hydrogen or the like in the room, and generates electricity. Since the temperature of the working fluid rises further due to the heat generated in the chemical reaction process, the working fluid is led out to the turbine 143 side from the outlet, expanded by the turbine 143, and returned to the power generation system 121 side.
The turbine 143 is rotationally driven by the working fluid discharged from the outlet on the air electrode side of the fuel cell 142.
The compressor 141 and the turbine 143 are pivotally supported by a common shaft 144. The turbine 143 serves as a power source for rotating the compressor 141.

In the APU 120 mounted on the aircraft according to this embodiment, the gas compressed by the compressor 128 is sent to the combustor 132 via the duct 130 and the mixer 131, mixed with the fuel by the combustor 132, and burned. To. The turbine 133 is rotationally driven by the combustion gas, and power is generated by the generator 110. Further, a part of the gas sent from the compressor 128 is supplied to the fuel cell system 122 as a working fluid via the flow path 123. The supplied working fluid is heated and pressurized by the compressor 141 to be controlled to a desired constant temperature, and is supplied to the inlet on the air electrode side of the fuel cell 142. The working fluid discharged from the outlet on the air electrode side of the fuel cell 142 is expanded by the turbine 143 and returned to the duct 130 on the power generation system 121 side via the flow path 154.

In the APU 120 mounted on the aircraft according to the present invention shown in FIG. 10, the temperature and pressure of the air introduced into the compressor 128 suddenly changes, and the temperature and pressure at the outlet of the compressor 128 suddenly fluctuate. However, the sudden fluctuation is suppressed by the compressor 141 inserted in the inlet of the fuel cell 142, and the working fluid in which the fluctuation is suppressed is supplied to the fuel cell 142, so that the cell voltage of the fuel cell 142 is supplied. Does not fluctuate, and the power generation performance does not deteriorate. Further, since the working fluid in which the fluctuation is suppressed is supplied to the fuel cell 142, it is possible to construct a system that can withstand a sudden pressure fluctuation. Furthermore, in the APU 120 mounted on the aircraft according to the embodiment of the present invention, the volume of such a compressor 141 can be sufficiently smaller than that of a heat exchanger or the like, so that the power generation performance can be suppressed while suppressing the increase in volume. Can be suppressed.

Further, since the fuel cell system 122 having the compressor 141 as a subsystem is independent of the power generation system 121 which is the main body, it is not necessary to incorporate a compressor or the like as a sub system into the power generation system 121 side, and the main body Since the operating environment of the fuel cell 142 on the subsystem side can be controlled independently of the operation of the power generation system 121, the fuel cell system 122 can be used in combination with various power generation systems 121.
[Technical scope of the present invention]
The present invention is not limited to the above embodiments, can be applied to various systems, and various modifications can be made, which are also within the technical scope of the present invention.

For example, although the above embodiment has described an example in which the present invention is applied to an aircraft, the present invention can be applied to an on-site or fixed ground power generation system, a marine fuel cell power generation system, or the like.

In the above embodiment, the air on the main body side is taken out from the duct and supplied to the subsystem side, but of course, it may be taken out from a place other than the duct. Similarly, the configuration was such that the gas was returned from the subsystem side to the duct on the main body side, but of course it may be configured to return the gas to a case other than the duct.

10 Aircraft 20 Jet engine / fuel cell hybrid system 21 Jet engine 22 Fuel cell system 23 Flow path 26 2-axis turbofan engine 28 High-pressure compressor 30 Duct 32 Combustor 33 High-pressure turbine 39 Second shaft 40 Heat exchanger 41 Compressor 42 Fuel cell 43 Turbine 44 Shaft 45 Motor 49 Air electrode 53 Outlet port 54 Flow path 61 Combustor 120 APU mounted on an aircraft
121 Power generation system 122 Fuel cell system 123 Flow path 110 Generator 128 Compressor 130 Duct 132 Combustor 133 Turbine 139 Axis 141 Compressor 142 Fuel cell 143 Turbine 144 Axis 154 Flow path

Claims (15)

A gas with a temperature and pressure is varied is supplied instantaneously in response a said compressed gas as the working fluid from the high pressure compressor of a heat engine having a high pressure compressor for compressing gas captured by the environment It ’s a fuel cell system,
With a fuel cell
The inlet on the air electrode side of the fuel cell is provided with a compressor that controls the working fluid supplied from the heat engine to a desired temperature and absorbs and supplies temperature and pressure fluctuations of the working fluid. Fuel cell system. The fuel cell system according to claim 1.
The compressor is rotary and
A fuel cell system further comprising a turbine that rotationally drives the compressor using a working fluid from an outlet on the air electrode side of the fuel cell as driving energy. The fuel cell system according to claim 2.
The compressor and the turbine are connected by a common central axis.
A fuel cell system further comprising a driving means for rotationally driving the central shaft. The fuel cell system according to any one of claims 1 to 3.
A fuel cell system further comprising a combustor that burns a working fluid from an outlet on the air electrode side of the fuel cell. The fuel cell system according to any one of claims 1 to 4.
A fuel cell system further comprising at least one of a heat exchanger or a heater that heats the working fluid supplied to the compressor. The fuel cell system according to any one of claims 1 to 5.
A fuel cell system in which the fuel cell is a solid oxide fuel cell. Combustion of the first compressor as a high pressure compressor for compressing gas, a fuel with a gas with a temperature and pressure is varied instantaneously in response to the first environment a gas which has been compressed by the compressor A heat engine having a first compressor for driving the first compressor and a first turbine for driving the first compressor using the combustion gas from the first compressor as a drive source.
A first flow path for taking out a part of the gas compressed by the first compressor and whose temperature and pressure may fluctuate instantaneously depending on the environment to the outside of the heat engine.
The gas is introduced as a working fluid of the fuel cell through the fuel cell and the first flow path, and the working fluid is controlled to a desired temperature at an introduction port on the air electrode side of the fuel cell, and A hybrid system including a fuel cell system having a second compressor that absorbs and supplies temperature and pressure fluctuations of the working fluid. The hybrid system according to claim 7.
The second compressor is a rotary type and
The fuel cell system is a hybrid system further comprising a second turbine that rotationally drives the second compressor using a working fluid from an outlet on the air electrode side of the fuel cell as driving energy. The hybrid system according to claim 8.
The second compressor and the second turbine are connected by a common central axis.
The fuel cell system is a hybrid system further including a driving means for rotationally driving the central shaft. The hybrid system according to any one of claims 7 to 9.
The fuel cell system is a hybrid system further including a second combustor that burns a working fluid from an outlet on the air electrode side of the fuel cell. The hybrid system according to any one of claims 7 to 10.
A hybrid system further comprising a second flow path for supplying the working fluid discharged from the fuel cell system to the first combustor of the heat engine. The hybrid system according to any one of claims 7 to 11.
A hybrid system further comprising at least one of a heat exchanger or a heater that heats the working fluid supplied to the second compressor. The hybrid system according to any one of claims 7 to 12.
A hybrid system in which the fuel cell is a solid oxide fuel cell. The hybrid system according to any one of claims 7 to 13 is installed.
An aircraft whose heat engine is a jet engine. The hybrid system according to any one of claims 7 to 13 is installed.
An auxiliary power unit mounted on an aircraft including a generator driven by the first turbine.