JP2008037731A - Hydrogen generation system, fuel cell system, and fuel cell automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen generation system which is suppressed in the amount of by-product gases generated and generates a necessary amount of hydrogen. <P>SOLUTION: The hydrogen generation system HGS is provided with a container (tank) 21 which holds a hydrogen storage material 30 which generates by-product gases in an amount which depends on the temperature, a temperature adjustment means (heating and cooling apparatus) 22 which adjusts the temperature in the container 21, and a control means (hydrogen generation controller HGC/thermometer 25) that estimates the quantity of by-product gases generated in the tank 21 and controls the temperature adjustment means 22 according to the estimated quantity. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a hydrogen generation system, a fuel cell system, and a fuel cell vehicle.

  In recent years, development competition for solid polymer fuel cells to be installed in fuel cell vehicles has been actively developed. In order to put such a fuel cell vehicle into practical use, it is desired to develop an efficient hydrogen storage and generation method using a hydrogen hydrogen storage material that is lightweight, has a high hydrogen storage density, and has a high resistance to repetition.

In view of this, it has been studied to use a hydrogen storage material containing a metal hydride and a metal amide compound in a reaction vessel (see Patent Document 1). A mixture of a metal hydride and a metal amide compound has very high performance as a hydrogen storage material, and the hydrogen generation rate increases as the temperature is increased.
JP 2006-7064 A

  However, when the hydrogen generation temperature is set to a high temperature, the generation reaction of ammonia as a by-product is more advantageous than the hydrogen generation reaction, and a necessary amount of hydrogen cannot be obtained.

  The present invention has been made to solve the above-described problems, and a hydrogen generation system according to the present invention includes a container containing a hydrogen storage material that generates a by-product gas in a temperature-dependent amount, and the container. A temperature adjusting means for adjusting the temperature inside, and a control means for estimating the amount of by-product gas generated in the container and controlling the temperature adjusting means based on the estimated amount.

  The fuel cell system according to the present invention uses the hydrogen generation system according to the present invention.

  A fuel cell vehicle according to the present invention uses the fuel cell system according to the present invention.

  ADVANTAGE OF THE INVENTION According to this invention, the generation amount of byproduct gas can be suppressed and the hydrogen generation system which can obtain a required quantity of hydrogen can be provided.

  According to the present invention, it is possible to provide a fuel cell system in which the total system weight and the total volume are reduced.

  According to the present invention, a lightweight and efficient fuel cell vehicle can be provided.

  Hereinafter, a hydrogen generation system, a fuel cell system, and a fuel cell vehicle according to the best embodiment of the present invention will be described with reference to the accompanying drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings schematically show the hydrogen generation system, the fuel cell system, and the fuel cell vehicle according to the embodiment of the present invention, and the ratios of the dimensions and the like are different from actual ones. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings is contained. Specific dimensions and the like should be determined in consideration of the following description.

<First Embodiment>
A hydrogen generation system, a fuel cell system, and a fuel cell vehicle according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a system diagram of a vehicle fuel cell system FCS (Fuel Cell System) including a hydrogen generation system HGS (H ₂ Generation System) according to the first embodiment of the present invention. FIG. 2 is a side view of the fuel cell vehicle 50 according to the first embodiment of the present invention. FIG. 3 is a main block diagram of the HGS. FIG. 4 is a gas generation characteristic diagram. FIG. 5 is an HGS control flow P1.

  The fuel cell system FCS is mounted on a fuel cell vehicle 50 shown in FIG. In FIG. 2, the fuel cell vehicle 50 has a hydrogen generator 20 (described later) installed and mounted at the rear. The hydrogen generation system HGS includes a tank (container) 21 in which a hydrogen storage material 30 that generates a by-product gas depending on a temperature is accommodated, and a heating / cooling device (temperature adjusting means) that adjusts the temperature in the tank 21. 22 and a control means for estimating the amount of by-product gas generated in the tank 21 and controlling the heating / cooling device 22 based on the estimated amount. This control means includes a hydrogen generation control device HGC and a thermometer (temperature measurement unit) 25 that measures the temperature in the tank 21, and the hydrogen generation control device HGC generates the temperature of the hydrogen storage material 30 and the generation of by-product gas. A memory (data storage unit) 29 that stores first data indicating the relationship with the quantity and a CPU (control unit) 28 that controls the data based on the measurement result are provided. This will be described in more detail below.

  The fuel cell system FCS includes a fuel cell stack 1 mounted on a vehicle, and a utility supply system USS that supplies utilities (humidified fuel, humidified oxidizer, refrigerant) to the fuel cell stack 1 and distributes them to each internal cell. (Utility Supply System) and utility discharge system UDS (Utility Discharge System) that collects the utility remaining in each single cell together with reaction products and discharges from fuel cell stack 1, and these fuel cell stack 1 and utility supply system USS And a fuel cell controller FCC (Fuel Cell Controller) that manages the utility discharge system UDS in a linked manner with a vehicle controller VC (Vehicular Controller).

  The utility supply system USS supplies a fuel supply system 2 that supplies humidified fuel (more specifically, humidified hydrogen gas) to the fuel inlet 1 a of the fuel cell stack 1 and an oxidant inlet 1 b of the fuel cell stack 1. An oxidant supply system 3 that supplies a humidified oxidant (more specifically, air humidified as necessary) and a refrigerant (more specifically, pure water) are supplied to the refrigerant inlet 1c of the fuel cell stack 1. And a refrigerant supply system 4.

  The fuel supply system 2 includes a hydrogen generation system HGS, a hydrogen pump HP (Hydrogen Pump) connected to the hydrogen generation system HGS on the suction side, a pressure reducing valve 2a interposed on the downstream side of the hydrogen pump HP, a flow It includes a valve 2b and a humidifier (not shown).

  The oxidant supply system 3 includes an air compressor AC (Air Compressor) that sucks and compresses air outside the vehicle, a decompression valve (not shown), a flow control valve, and a humidifier that are provided downstream of the air compressor AC. Including

  The refrigerant supply system 4 is provided with a temperature-controllable refrigerant storage tank (not shown), a refrigerant pump CP (Coolant Pump) connected to the refrigerant storage tank on the suction side, and a downstream side of the refrigerant pump CP. In addition, a pressure reducing valve and a flow control valve (not shown) are included.

  The utility discharge system UDS includes fuel, oxidant and refrigerant discharge lines connected to the fuel, oxidant and refrigerant discharge ports of the fuel cell stack 1, respectively, of which the refrigerant discharge line is connected to a refrigerant storage tank, A refrigerant circulation system is configured in cooperation with the supply system 4.

  The fuel cell control device FCC outputs control signals C1 to C5 corresponding to the operation state of the hydrogen generation system HGS and the vehicle, and a fuel supply system 2 including a hydrogen pump HP, a pressure reducing valve 2a, and a flow control valve 2b, The oxidant supply system 3 including the air compressor AC and the refrigerant supply system 4 including the refrigerant pump CP are appropriately controlled.

  In the present embodiment, the hydrogen generation system HGS is interposed between the hydrogen generator 20 as a hydrogen supply source and the hydrogen generator 20 and the hydrogen pump HP, and appropriately collects and releases hydrogen to supply hydrogen. A hydrogen reservoir 40 as a pressure accumulator that stabilizes the amount and a hydrogen generation controller HGC (Hydrogen Generation Controller) that manages the hydrogen generation system HGS in connection with the fuel cell control device FCC are provided. Not.

  The hydrogen generator 20 includes a cylindrical hydrogen tank 21, and the tank 21 is separated from the entire circumference of the side wall 21b between the separable tank top (right end in the figure) 21a and tank bottom (left end in the figure) 21c. A pressure regulating valve 23 and a flow regulating valve 24 interposed between a heating / cooling device 22 for heating / cooling the tank 21, and a hydrogen supply line communicating with the tank top 21 a and a connecting line 41 of the hydrogen reservoir 40. With. The tank 21 contains a preferably porous hydrogen storage material 30 that occludes hydrogen (that is, binds and stores) or dissociates and generates hydrogen. Note that the connecting pipe 41 of the hydrogen reservoir 40 is provided with a pressure regulating valve 42 and a flow regulating valve 43 downstream thereof, that is, between the hydrogen reservoir 40 and the hydrogen pump HP.

  The heating / cooling device 22 includes a resistance heating type or induction heating type electric heater 22b as a heater for heating the tank 21 via a heating wire 22a wound around the tank 21, and the tank 21 in the same manner as the electric heater 22b. And a cooling device 22d as a cooler that cools the tank 21 through a refrigerant pipe 22c wound around. The electric heater 22b and the cooling device 22d are not operated simultaneously.

  The hydrogen storage material 30 is preferably configured as an assembly in which a large number of molding pieces are combined. The shape of each piece and the assembly can be arbitrarily set, and rod-like base materials may be arranged in parallel, but in this embodiment, thin fan-shaped pieces having different radii are combined concentrically and stacked. As a result, nested aggregates 31 and 32 (more specifically, coaxial cylinders spaced apart by a predetermined gap) are formed. An axial through hole 31a is provided at the center of the innermost cylindrical assembly 31, and the outermost cylindrical assembly 32 forms a nesting hole 32a having a larger diameter than the inner cylindrical assembly 31. An outer diameter smaller than the inner diameter of the side wall 21b of the tank 21 is given, a predetermined gap is provided, and a hydrogen gas diffusion / conduction path is secured as necessary.

  When the hydrogen storage material 30 is made of a hydrogen storage metal having high thermal conductivity, the aggregates 31 and 32 may be rigidly and integrally formed by joining the molding pieces. However, including the case, preferably, a lattice-like or honeycomb-like holding frame or matrix-like shape made of a metal having high thermal conductivity is provided between each of the aggregates 31, 32 or its constituent pieces and the tank 21. Contact is provided through a holding net (not shown), thereby achieving positioning and holding of the entire hydrogen storage material 30 and uniform temperature control.

Divided by the average density of the molded piece on the weight of the hydrogen storage material 30, i.e., the actual volume of the hydrogen storage material 30 (hereinafter, represented by V _30.), The volume of the tank 21 (hereinafter, represented by V ₂₁ .) Is smaller (ie, V ₃₀ / V ₂₁ <1), and has a volume V (= V ₂₁ −V ₃₀ ) corresponding to the difference (V ₂₁ −V ₃₀ ) therebetween, or further includes a holding frame or a holding net. In this case, a hydrogen gas atmosphere having a volume V (= V ₂₁ −V ₃₀ −V _m ) corresponding to a value obtained by subtracting the volume (hereinafter referred to as V _m ) is the inner wall of the tank 21 when the hydrogen generator 20 is operated. And the interface between the molding pieces constituting the hydrogen storage material 30 are filled.

The hydrogen gas atmosphere, the temperature (hereinafter,. Represented by T _a) is, the hydrogen storage material 30 itself heat transfer effect (Alternatively, heat transfer effect was increased by the holding frame or holding network) by substantially uniform temperature control Is done. Further, the pressure P of the hydrogen gas atmosphere is regulated almost uniformly within a significant time exceeding the diffusion rate control of the hydrogen gas to a value corresponding to the average gas pressure in the vicinity of the interface of the forming piece. Accordingly, the hydrogen gas concentration C is also made substantially uniform within a significant time.

  A sensor holding plug 21d is fitted to the tank bottom 21c of the tank 21, and thereby the temperature sensor S1, the pressure sensor S2, and the generated gas concentration sensor S3 are held. The temperature sensor S1 is a thermometer 25 composed of a thermocouple. The temperature sensor S1 is inserted into the through hole 31a at the center of the cylindrical assembly 31 and is in contact with or embedded in the assembly 31 with hydrogen. An average temperature (or representative temperature) T of the storage material 30 is detected. The pressure sensor S2 includes a gas pressure gauge 26, and detects the pressure P of the hydrogen gas atmosphere. The generated gas concentration sensor S3 includes a generated gas concentration meter 27 including an impurity concentration meter operable at room temperature or higher, and detects the hydrogen concentration C and the impurity concentration Ci in the generated gas.

  The hydrogen generation control device HGC includes the temperature sensor S1, the temperature T [° C.] of the hydrogen storage material 30 detected by the pressure sensor S2 and the generated gas concentration sensor S3, the pressure P [Pa] of the hydrogen gas atmosphere, and the generated gas The hydrogen concentration C [%] is sampled, corrected if necessary, processed in accordance with a command from the fuel cell control device FCC, and the control signals C6 to C8 are output. By controlling the pressure regulating valve 23 and the flow regulating valve 24 on the upstream side of the hydrogen reservoir 40, the hydrogen generation amount of the hydrogen generating device 20 is controlled, and the control signals C9 to C10 are output. By controlling the pressure regulating valve 42 and the flow regulating valve 43 on the downstream side, the hydrogen supply amount of the hydrogen generation system HGS is controlled.

  The heating / cooling device control signal C6 includes a heater control signal C61 and a cooler control signal C62. When the heating / cooling device 22 is controlled by the heating / cooling device control signal C6 and thereby the temperature T of the hydrogen storage material 30 is increased, hydrogen is dissociated and diffused from the interface and the inside thereof and released into the tank 21, Conversely, when the temperature T of the hydrogen storage material 30 decreases, the hydrogen in the tank 21 is diffused and occluded from the interface of the hydrogen storage material 30 to the inside, and combined.

  Next, the operation of the hydrogen generation system HGS according to the first embodiment will be described with reference to FIGS. FIG. 3 shows a block diagram of the main part of the HGS, FIG. 4 shows a gas generation characteristic diagram, and FIG. 5 shows a control flow P1 of the HGS.

  As shown in FIG. 3, the hydrogen generation control device HGC includes a central processing unit (CPU) 28 and a memory 29 as a peripheral device of the CPU 28, and the CPU 28 performs calculations related to the control flow P <b> 1 shown in FIG. 5. The memory 29 stores programs and data necessary for these operations. The stored data includes data of a by-product gas generation characteristic curve in the gas generation characteristic diagram shown in FIG.

  FIG. 4 shows a gas generation characteristic diagram when an Mg—Li—N—H-based hydrogen storage material is used as the hydrogen storage material 30. When the Mg—Li—N—H based hydrogen storage material is used, hydrogen is generated by the reaction of the following formula (1). The material that can be described by the reaction formula shown in the formula (1) is one of excellent hydrogen storage materials capable of releasing a large amount of hydrogen.

3Mg (NH ₂ ) ₂ + 12LiH⇔Mg ₃ N ₂ + 4Li ₃ N + 12H ₂ Formula (1)
In the generation of gas, the generation of hydrogen represented by the formula (1) is dominant up to the temperature T1 (impure gas generation start temperature). However, as the temperature in the tank 21 becomes higher than T1, the generation amount of impure gas (here, ammonia gas) which is a by-product gas increases, and at a temperature higher than the temperature T2 (impure gas rapid increase temperature), the equation Due to the reaction shown in (2), generation of ammonia as an impure gas becomes dominant.

Mg (NH ₂ ) ₂ → MgNH + NH ₃ Formula (2)
The HGC issues a control signal to the heating / cooling device 22 according to the control map shown in Table 1.

  FIG. 5 shows a control flow P1 of the hydrogen generation system according to the first embodiment. The control flow P1 first reads out the control map shown in Table 1 in step S0, and proceeds to step S1.

  In step S <b> 1, a heater-on command is issued to the heating / cooling device 22. When the predetermined time has passed, the process proceeds to the next step S2.

  In step S2, the temperature T inside the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T1 (impure gas generation start temperature). If T <T1 (YES), the process proceeds to step S3. When T <T1 is not satisfied (NO), that is, when T1 ≦ T, the process proceeds to the next step S5.

  In step S3, the control method <heating 3> is selected, and the process proceeds to step S4.

  In step S4, a heater-on command is output to the heating / cooling device 22.

  In step S5, the temperature T inside the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T2 (impure gas rapid increase temperature). If T <T2 (YES), the process proceeds to step S6. When T <T2 is not satisfied (NO), that is, when T2 ≦ T, the process proceeds to the next step S8.

  In step S6, the control method <hold 2> is selected, and the process proceeds to step S7.

  In step S7, a heater-off command is output to the heating / cooling device 22.

  In step S8, the control method <cooling 1> is selected, and the process proceeds to step S9.

  In step S <b> 9, a cooler-on command is output to the heating / cooling device 22. Note that the cooler turns off when the cooler-on signal disappears.

  That is, in the first embodiment, heating and cooling are determined based on the value of the thermometer 25, and the generation of impure gas is suppressed. In step S <b> 1, the tank 21 is heated by the heating / cooling device 22 to generate hydrogen from the hydrogen storage material 30 stored in the tank 21. Next, when the temperature T in the tank 21 is T <T1 in step S2, since the hydrogen flow rate is insufficient and no impure gas is generated, the temperature in the tank 21 is increased to increase the hydrogen flow rate. The heater-on command is output to the heating / cooling device 22 at.

  On the other hand, in the case where the temperature T in the tank 21 is T1 ≦ T <T2, the hydrogen flow rate increases with heating and is higher than the impure gas generation start temperature, so that the temperature of the tank 21 is lowered. A heater-off command is output to the heating / cooling device 22. Since the hydrogen generation reaction is an endothermic reaction, the temperature in the tank 21 is lowered by maintaining the temperature in the tank 21.

  In step S2, when T2 ≦ T, overshoot is observed in the heating process, and the inside of the tank 21 becomes the impure gas rapid increase temperature or higher, so that when it is further heated, the impure gas ammonia rapidly increases. In order to suppress this, a cooler-on command is output to the heating / cooling device 22 in step S9.

  A hydrogen generation system according to a first embodiment of the present invention includes a container containing a hydrogen storage material that generates a by-product gas in an amount dependent on temperature, temperature adjusting means for adjusting the temperature in the container, And a control means for controlling the temperature adjusting means based on the estimated amount, and the control means determines the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated. Since the data storage unit for storing the first data shown, the temperature measurement unit for measuring the temperature in the container, and the control unit for controlling the data based on the measurement result, the amount of generated by-product gas is reduced. It is possible to provide a hydrogen generation system that can suppress and obtain a necessary amount of hydrogen. That is, when the relationship between the amount of by-product gas generated and the temperature of the hydrogen storage material is known, the concentration of by-product gas contained in the generated gas can be calculated by measuring the temperature of the hydrogen storage material. . For this reason, the control of the temperature adjusting means can be determined using the temperature of the hydrogen storage material as a parameter, and the concentration of the by-product gas contained in the generated gas can be reduced.

  It is desirable that the temperature measurement unit can directly measure the temperature of the hydrogen storage material filled in the container, and it is desirable that the temperature measurement unit does not contact the heating channel. Further, although the number of temperature measuring units can be controlled even by one, it is desirable that the number of temperature measuring units is large because heat distribution is generated in the container.

  As the temperature adjusting means, a heat medium method in which a liquid or a gas is circulated in the pipe or a method in which a heating wire is laid in the material is assumed.

  In addition, in order to obtain the first data indicating the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated, the temperature of the hydrogen storage material and the amount of by-product gas are determined by experiments using a small amount of sample in advance. It is necessary to conduct an experiment to obtain the relationship with the generation amount.

  In the conventional method for judging only from the hydrogen supply amount, the operation of the hydrogen generation system in the temperature range where the by-product gas is generated cannot be prevented. However, according to the first embodiment of the present invention, the by-product is generated. The system is not operated in the temperature range where the gas is generated, and the concentration of the by-product gas contained in the generated hydrogen can be reduced to about 1/10 of the conventional one.

  When a material system that generates two or more types of by-product gases is used, the lower limit of the temperature at which the by-product gases are generated varies depending on the gas type. For this reason, in order to efficiently suppress the amount of by-product gas generated, it is effective to control the generated gas based on the data of the gas species generated on the lower temperature side. In other words, the first data indicating the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated is that the temperature of the hydrogen storage material and the generation of the by-product gas having the lowest generation start temperature among the by-product gases. It is preferable to include data indicating the relationship with the quantity, and the control means performs control using this data as a control condition.

  As the hydrogen storage material, an Mg—Li—N—H-based hydrogen storage material mainly composed of a material composed of a metal selected from alkali metals and alkaline earth metal elements, nitrogen, and hydrogen is used in the present embodiment. . As a Mg—Li—N—H-based hydrogen storage material, the main component of metal ions is Li ions, and the Li ions are partially or entirely replaced with alkali metals such as Mg, Ca, Na, or alkaline earth metals. The material exhibits effective performance as a hydrogen storage material. This hydrogen storage material can be obtained by adding transition metal species such as Ti, Cr, Mn, Fe, Co, Ni, Nb, Zr and W, or by adding inorganic materials such as carbon-based materials, silica or alumina. Hydrogen storage performance can be improved. Since these materials are materials that generate gas species other than hydrogen by a side reaction, heating can be performed under conditions advantageous for the hydrogen releasing reaction by performing control using the hydrogen generation system according to this embodiment. And the generation concentration of the by-product gas can be reduced.

  In addition, as a hydrogen storage material, for example, a material that generates hydrogen by the reaction represented by the formula (3), that is, a material composed of a metal selected from an alkali metal and an alkaline earth metal element, boron, and hydrogen is a main component. Materials may be used.

LiBH ₄ → LiH + B + 3 / 2H ₂ Formula (3)
The material that can be described by the reaction formula shown in the formula (3) is one of excellent hydrogen storage materials that can release a large amount of hydrogen in the same manner as the Mg—Li—N—H hydrogen storage material. As shown in Formula (4) and Formula (5), a more excellent hydrogen releasing material can be obtained by adding a metal hydride, metal amidide or hydrogenated carbon to LiBH ₄ .

LiBH ₄ + 2LiNH ₂ → Li ₃ BN ₂ + 4H ₂ Formula (4)
2LiBH ₄ + MgH ₂ → 2LiH + MgB ₂ + 4H ₂ (5)
Moreover, as a hydrogen storage material, as shown in Formula (6), a compound containing nitrogen, boron, and hydrogen as main components may be included.

NH ₃ BH ₃ → NHBH + 2H ₂ Formula (6)
The material that can be described by the reaction formula shown in the formula (6) is one of excellent hydrogen storage materials that can release a large amount of hydrogen in the same manner as the above-described material. However, unlike the above reaction, the reaction shown in Formula (6) is an exothermic reaction, and thus overshoot is likely to occur during heating. For this reason, it is necessary to set a parameter different from the case where the above-described material is used.

  Since the fuel cell system according to the first embodiment of the present invention uses the hydrogen generation system according to the first embodiment of the present invention, the amount of by-product gases other than hydrogen is reduced, and by-product gas removal is achieved. Because the filter weight is reduced, the system becomes compact. That is, when a by-product gas is generated, it is necessary to improve the purity of the supplied hydrogen by installing a filter made of a carbon-based material or a ceramic material on the fuel supply system 2 side. If there are many, the weight of the filter that must be mounted increases. For this reason, controlling the amount of heating and suppressing the amount of by-product gas generated leads to a reduction in system weight. The fuel cell system according to the first embodiment of the present invention can provide a fuel cell system with a reduced total system weight and total volume.

  Moreover, since the fuel cell system according to the first embodiment of the present invention has a compact fuel cell system, a light weight fuel cell vehicle can be configured. FIG. 2 shows a fuel cell vehicle 50 equipped with the fuel cell system according to the embodiment of the present invention, and is a diagram in which the hydrogen generator 20 shown in FIG. At this time, in addition to the interior of the engine room or the trunk room or the interior of the vehicle compartment such as the floor portion under the seat, the hydrogen generator 20 can be installed outside the interior of the vehicle compartment such as the upper part of the roof.

  In the fuel cell vehicle according to the first embodiment of the present invention, a fuel cell system having a reduced total system weight and total volume is mounted, so that the vehicle weight is reduced, light weight can be improved, and fuel efficiency can be improved. A battery car can be provided. Further, the vehicle compartment can be used more widely by reducing the total volume of the fuel cell system.

<Second Embodiment>
Next, a hydrogen generation system according to a second embodiment of the present invention will be described with reference to FIGS. Since the fuel cell system and the fuel cell vehicle are the same as those in the first embodiment, description thereof will be omitted. FIG. 6 shows a principal block diagram of the hydrogen generation system HGS according to the second embodiment, and FIG. 7 shows a control flow P2 of the HGS. When the hydrogen generation system of the second embodiment is compared with that of the first embodiment, the determination of heating or cooling is made based on the measurement result by the generated gas concentration meter 27, not by the measurement result by the thermometer 25. Is different. Since the other configurations are substantially the same, the same reference numerals are given to the same components and the description thereof is omitted.

  The hydrogen generation system HGS includes a tank (container) 21 in which a hydrogen storage material 30 that generates a by-product gas depending on a temperature is accommodated, and a heating / cooling device (temperature adjusting means) that adjusts the temperature in the tank 21. 22 and a control means for estimating the amount of by-product gas generated in the tank 21 and controlling the heating / cooling device 22 based on the estimated amount. This control means includes a hydrogen generation control device HGC and a generated gas concentration meter (concentration measuring unit) 27 that measures the concentration of the by-product gas in the tank 21, and the hydrogen generation control device HGC performs control based on the measurement result. A CPU (control unit) 28 is provided. This will be described in more detail below.

  As shown in FIG. 6, the hydrogen generation control device HGC includes a central processing unit (CPU) 28 and a memory 29 as a peripheral device of the CPU 28, and the CPU 28 performs operations related to the control flow P <b> 2 shown in FIG. 7. The memory 29 stores programs and data necessary for these operations.

  Also in the second embodiment, an Mg—Li—N—H-based hydrogen storage material is used as the hydrogen storage material 30 as in the first embodiment. When the Mg—Li—N—H-based hydrogen storage material is used, hydrogen is generated by the reaction of the above formula (1).

The HGC issues a control signal to the heating / cooling device 22 according to the control map shown in Table 2.

FIG. 7 shows a control flow P2 of the hydrogen generation system according to the second embodiment. The control flow P2 first reads the control map shown in Table 2 in step S10, and proceeds to step S11.

  In step S <b> 11, a heater-on command is issued to the heating / cooling device 22. When the predetermined time has passed, the process proceeds to the next step S12.

  In step S12, the concentration of impure gas that is a by-product gas inside the tank 21 is measured by the generated gas concentration meter 27, and it is determined whether or not the impure gas is detected. When the impure gas is not detected (NO), the process proceeds to step S13. If the impure gas is detected (YES), the process proceeds to the next step S15.

  In step S13, the control method <heating 3> is selected, and the process proceeds to step S14.

  In step S14, a heater-on command is output to the heating / cooling device 22.

  In step S15, the concentration of the impurity gas inside the tank 21 is measured by the generated gas concentration meter 27, and it is determined whether or not the impurity gas concentration Ci <1%. If Ci <1% (YES), the process proceeds to step S16. When Ci <1% is not satisfied (NO), that is, when 1% ≦ Ci, the process proceeds to the next step S18.

  In step S16, the control method <hold 2> is selected, and the process proceeds to step S17.

  In step S17, a heater-off command is output to the heating / cooling device 22.

  In step S18, the control method <cooling 1> is selected, and the process proceeds to step S19.

  In step S19, a cooler-on command is output to the heating / cooling device 22.

  That is, in the second embodiment, heating and cooling are determined based on the concentration of the impure gas detected by the generated gas concentration meter 27, and the generation of the impure gas is suppressed. In step S <b> 11, the tank 21 is heated by the heating / cooling device 22 to generate hydrogen from the hydrogen storage material 30 stored in the tank 21. Next, when no impure gas is detected in step S12 (NO), the hydrogen flow rate is insufficient. Therefore, in order to increase the hydrogen flow rate by raising the temperature in the tank 21, a heater-on command is sent to the heating / cooling device in step S14. 22 for output.

  On the other hand, in step S12, when the impure gas is detected and the concentration is Ci <1%, the hydrogen flow rate increases with heating, and the generation of the impure gas is confirmed. Therefore, in order to lower the temperature of the tank 21, a heater-off command is output to the heating / cooling device 22 in step S17. Since the hydrogen generation reaction is an endothermic reaction, the temperature in the tank 21 is lowered by maintaining the temperature in the tank 21.

  In step S12, if 1% ≦ Ci, overshoot is observed in the heating process, and the concentration of impure gas rises rapidly, so a cooler-on command is output to the heating / cooling device 22 in step S19. Note that the density value in step S12 varies depending on the required value of the apparatus.

  A hydrogen generation system according to a second embodiment of the present invention includes a container that contains a hydrogen storage material that generates a by-product gas in an amount dependent on temperature, a temperature adjusting unit that adjusts the temperature in the container, And a control means for controlling the temperature adjusting means based on the estimated amount, and the control means includes a concentration measuring unit for measuring the concentration of the by-product gas in the container, Since a control unit that performs control based on the measurement result is provided, it is possible to provide a hydrogen generation system that can suppress the generation amount of by-product gas and obtain a necessary amount of hydrogen. That is, by measuring the concentration of the by-product gas, the container temperature adjusting means can be directly controlled.

  The concentration measuring unit may be installed either inside the container filled with the hydrogen storage material or on the path from the container filled with the hydrogen storage material to the fuel cell. Preferably, the inside of the container or the container In the path from the fuel cell to the fuel cell, it is preferable to be near the container.

  Since the gas concentration needs to be measured in the range of the% level to the ppm level, it is desirable to use an analyzer using electrical conductivity measurement, density measurement by ultrasonic waves, ionization detection method, or the like.

  In the conventional method for judging from only the hydrogen supply amount, the operation of the hydrogen generation system in the temperature range where the by-product gas is generated cannot be prevented. However, according to the second embodiment of the present invention, the by-product is generated. The system is not operated in the temperature range where the gas is generated, and the concentration of the by-product gas contained in the generated hydrogen can be reduced to about 1/10 of the conventional one.

<Third Embodiment>
Next, a hydrogen generation system according to a third embodiment of the present invention will be described with reference to FIGS. Since the fuel cell system and the fuel cell vehicle are the same as those in the first embodiment, description thereof will be omitted. FIG. 8 shows a principal block diagram of the hydrogen generation system HGS, FIG. 9 shows a gas generation characteristic diagram, and FIG. 10 shows a control flow P3 of the HGS. In the hydrogen generation system according to the third embodiment, the control map prepared from the hydrogen generation characteristic curve and the impure gas characteristic curve shown in FIG. 9 prepared in advance is read to determine whether the tank 21 is heated or cooled. It differs from the form. Since other configurations are substantially the same as those in the first embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

  The hydrogen generation system HGS includes a tank (container) 21 in which a hydrogen storage material 30 that generates a by-product gas depending on a temperature is accommodated, and a heating / cooling device (temperature adjusting means) that adjusts the temperature in the tank 21. 22 and a control means for estimating the amount of by-product gas generated in the tank 21 and controlling the heating / cooling device 22 based on the estimated amount. This control means includes a hydrogen generation control device HGC and a thermometer (temperature measurement unit) 25 that measures the temperature in the tank 21, and the hydrogen generation control device HGC generates the temperature of the hydrogen storage material 30 and the generation of by-product gas. A memory (data storage unit) 29 that stores first data indicating the relationship with the quantity and a CPU (control unit) 28 that controls the data based on the measurement result are provided. The first data includes second data indicating the relationship between the temperature of the hydrogen storage material 30 and the amount of hydrogen gas generated. This will be described in more detail below.

  As shown in FIG. 8, the hydrogen generation control device HGC includes a central processing unit (CPU) 28 and a memory 29 as a peripheral device of the CPU 28. The CPU 28 performs computations related to the control flow P3 shown in FIG. The memory 29 stores programs and data necessary for these operations. The stored data includes the gas generation characteristic diagram shown in FIG.

  FIG. 9 shows a gas generation characteristic diagram when an Mg—Li—N—H hydrogen storage material is used as the hydrogen storage material 30. When the Mg—Li—N—H based hydrogen storage material is used, hydrogen is generated by the reaction of the following formula (7).

Mg (NH ₂ ) ₂ + 2LiH → MgLi ₂ (NH) ₂ + 2H ₂ Formula (7)
When the temperature in the tank 21 is lower than T1 (set to an appropriate amount of H ₂ gas), no impure gas as a by-product gas is generated. When the temperature in the tank becomes equal to or higher than T2 (impure gas generation start temperature), ammonia, which is an impure gas, is generated by the reaction shown in Formula (8).

Mg (NH ₂ ) ₂ → MgNH + NH ₃ Formula (8)
Further, as the temperature in the tank 21 becomes higher than T2, the amount of impure gas generated increases, but until the temperature in the tank 21 reaches T3 (impure gas rapid increase temperature), the generation of hydrogen shown in the equation (7) occurs. Dominant. When the temperature in the tank 21 is higher than T3, generation of ammonia as an impure gas becomes dominant due to the reaction shown in the equation (8).

The HGC issues a control signal to the heating / cooling device 22 according to the control map shown in Table 3.

  FIG. 10 shows a control flow P3 of the hydrogen generation system according to the third embodiment. The control flow P3 first reads out the control map shown in Table 3 in step S20, and proceeds to step S21.

  In step S 21, a heater-on command is issued to the heating / cooling device 22. When the predetermined time has passed, the process proceeds to the next step S22.

  In step S22, the temperature T in the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T2 (impure gas generation start temperature). If T <T2 (YES), the process proceeds to step S23. When T <T2 is not satisfied (NO), that is, when T2 ≦ T, the process proceeds to the next step S28.

In step S23, the temperature T inside the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T1 (appropriate H ₂ gas temperature). If T <T1 (YES), the process proceeds to step S24. When T <T1 is not satisfied (NO), that is, when T1 ≦ T, the process proceeds to the next step S26.

  In step S24, the control method <heating 4> is selected, and the process proceeds to step S25.

  In step S25, a heater-on command is output to the heating / cooling device 22.

  In step S26, the control method <holding 3> is selected, and the process proceeds to step S27.

  In step S27, a heater-off command is output to the heating / cooling device 22.

  In step S28, the temperature T in the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T3 (impure gas rapid increase temperature). If T <T3 (YES), the process proceeds to step S29. When T <T3 is not satisfied (NO), that is, when T3 ≦ T, the process proceeds to the next step S31.

  In step S29, the control method <hold 2> is selected, and the process proceeds to step S30.

  In step S30, a heater-off command is output to the heating / cooling device 22.

  In step S31, the control method <cooling 1> is selected, and the process proceeds to step S32.

  In step S <b> 32, a cooler-on command is output to the heating / cooling device 22.

  That is, in the third embodiment, heating and cooling are determined based on the value of the thermometer 25, and the generation of impure gas is suppressed. In step S <b> 21, the tank 21 is heated by the heating / cooling device 22 to generate hydrogen from the hydrogen storage material 30 stored in the tank 21. When the temperature T in the tank T is T <T1, since the hydrogen flow rate is insufficient and no impure gas is generated, a heater-on command is issued in step S24 in order to increase the temperature in the tank 21 and increase the hydrogen flow rate. Output to the heating / cooling device 22.

When the temperature T in the tank 21 is T1 ≦ T <T2, the hydrogen flow rate increases as it is heated, and is not more than the impure gas generation start temperature and is at an appropriate amount of H ₂ gas. In step S27, a heater-off command is output to the heating / cooling device 22.

  When the temperature T in the tank 21 is T2 ≦ T <T3, an overshoot is observed in the heating process, which is equal to or higher than the impure gas generation start temperature. In order to lower the temperature, a heater-off command is output to the heating / cooling device 22 in step S30. Since the hydrogen generation reaction is an endothermic reaction, the temperature in the tank 21 is lowered by maintaining the temperature in the tank 21.

  In the case of T3 ≦ T, overshoot is observed in the heating process, and the temperature becomes higher than the impure gas rapid increase temperature. Therefore, when further heated, ammonia which is an impure gas rapidly increases. In order to suppress this, a cooler-on command is output to the heating / cooling device 22 in step S32.

  A hydrogen generation system according to a third embodiment of the present invention includes a container that stores a hydrogen storage material that generates a by-product gas in an amount dependent on temperature, temperature adjusting means that adjusts the temperature in the container, And a control means for controlling the temperature adjusting means based on the estimated amount, and the control means determines the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated. A data storage unit for storing the first data to be shown, a temperature measurement unit for measuring the temperature in the container, and a control unit for controlling the data based on the measurement result. Since the second data indicating the relationship between the temperature of the material 30 and the generation amount of hydrogen gas is included, it is possible to provide a hydrogen generation system that can suppress the generation amount of by-product gas and obtain a necessary amount of hydrogen. That is, when the relationship between the amount of by-product gas generated and the temperature of the hydrogen storage material is known, the concentration of by-product gas contained in the generated gas can be calculated by measuring the temperature of the hydrogen storage material. . For this reason, the control of the temperature adjusting means can be determined using the temperature of the hydrogen storage material as a parameter, and the concentration of the by-product gas contained in the generated gas can be reduced. In addition, by using the excess or deficiency of the hydrogen supply amount for the judgment of the control means for controlling the temperature adjusting means, the use of the hydrogen generation system at a temperature with a low by-product gas concentration while obtaining the necessary hydrogen supply amount. Enable.

  As in the first embodiment, the first data indicating the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated, and the second data indicating the relationship between the temperature of the hydrogen storage material and the amount of generated hydrogen gas. In order to obtain this data, the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated and the relationship between the temperature of the hydrogen storage material and the amount of hydrogen gas generated through experiments using a small amount of sample in advance. It is necessary to carry out the experiment to obtain.

  In the conventional method for judging from only the hydrogen supply amount, the operation of the hydrogen generation system in the temperature range where the by-product gas is generated cannot be prevented. However, according to the third embodiment of the present invention, the by-product is generated. The system is not operated in the temperature range where the gas is generated, and the concentration of the by-product gas contained in the generated hydrogen can be reduced to about 1/10 of the conventional one.

<Fourth embodiment>
Next, a hydrogen generation system according to a fourth embodiment of the present invention will be described with reference to FIGS. Since the fuel cell system and the fuel cell vehicle are the same as those in the first embodiment, description thereof will be omitted. FIG. 11 is a principal block diagram of the HGS, and FIG. 12 shows a control flow P4 of the HGS. The hydrogen generation system according to the fourth embodiment is different from the first embodiment in that the determination of heating and cooling of the tank 21 is performed based on the measurement result of the thermometer 25 and the hydrogen supply amount detected by the generated gas concentration meter 27. Since other configurations are substantially the same as those in the first embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

  The hydrogen generation system HGS includes a tank (container) 21 in which a hydrogen storage material 30 that generates a by-product gas depending on a temperature is accommodated, and a heating / cooling device (temperature adjusting means) that adjusts the temperature in the tank 21. 22 and a control means for estimating the amount of by-product gas generated in the tank 21 and controlling the heating / cooling device 22 based on the estimated amount. This control means includes a hydrogen generation control device HGC and a thermometer (temperature measurement unit) 25 that measures the temperature in the tank 21, and the hydrogen generation control device HGC generates the temperature of the hydrogen storage material 30 and the generation of by-product gas. A memory (data storage unit) 29 that stores first data indicating the relationship with the quantity and a CPU (control unit) 28 that controls the data based on the measurement result are provided. The first data includes second data indicating the relationship between the temperature of the hydrogen storage material 30 and the amount of hydrogen gas generated. Further, a fuel supply system (hydrogen supply path) 2 for supplying hydrogen gas from the tank 21 to the outside is provided, and the control means performs control using the amount of hydrogen gas supplied from the fuel supply system 2 to the outside as a control condition. This will be described in more detail below.

  As shown in FIG. 11, the hydrogen generation control device HGC includes a central processing unit (CPU) 28 and a memory 29 as a peripheral device of the CPU 28. The CPU 28 performs computations related to the control flow P4 shown in FIG. The memory 29 stores programs and data necessary for these operations. The stored data includes the gas generation characteristic diagram shown in FIG.

  The fuel cell control device FCC outputs control signals C1 to C3 corresponding to the operation state of the hydrogen generation system HGS and the vehicle, and appropriately controls the fuel supply system 2 including the hydrogen pump HP, the pressure reducing valve 2a, and the flow control valve 2b. Control.

  Also in the fourth embodiment, an Mg—Li—N—H-based hydrogen storage material is used as the hydrogen storage material 30 as in the first embodiment. When the Mg—Li—N—H-based hydrogen storage material is used, hydrogen is generated by the reaction of the above formula (1).

The HGC issues a control signal to the heating / cooling device 22 according to the control map shown in Table 4.

  FIG. 12 shows a control flow P4 of the hydrogen generation system according to the fourth embodiment. The control flow P4 first reads out the control map shown in Table 4 in step S40, and proceeds to step S41.

  In step S41, a heater-on command is issued to the heating / cooling device 22. When the predetermined time has passed, the process proceeds to the next step S42.

  In step S42, the temperature T in the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T2 (impure gas generation start temperature). If T <T2 (YES), the process proceeds to step S43. When T <T2 is not satisfied (NO), that is, when T2 ≦ T, the process proceeds to the next step S48.

  In step S43, it is determined whether the supply amount of hydrogen is sufficient. If hydrogen is insufficient, the process proceeds to step S44. If hydrogen is sufficient, the process proceeds to step S46.

  In step S44, the control method <heating 4> is selected, and the process proceeds to step S45.

  In step S45, a heater-on command is output to the heating / cooling device 22.

In step S46, the control method <holding 3> is selected, and the process proceeds to step S47.
In step S47, a heater-off command is output to the heating / cooling device 22.

  In step S48, the temperature T inside the tank 21 is measured by the thermometer 25, and it is determined whether or not T <T3 (impure gas rapid increase temperature). If T <T3 (YES), the process proceeds to step S49. When T <T3 is not satisfied (NO), that is, when T3 ≦ T, the process proceeds to the next step S51.

  In step S49, the control method <hold 2> is selected, and the process proceeds to step S50.

  In step S50, a heater-off command is output to the heating / cooling device 22.

  In step S51, the control method <cooling 1> is selected, and the process proceeds to step S52.

  In step S52, a cooler-on command is output to the heating / cooling device 22.

  That is, in the fourth embodiment, heating and cooling are determined based on the hydrogen supply amount detected by the value of the thermometer 25, and the generation of impure gas is suppressed. In step S <b> 41, the tank 21 is heated by the heating / cooling device 22 to generate hydrogen from the hydrogen storage material 30 stored in the tank 21. When the temperature T in the tank 21 is T <T2 and the supply amount of hydrogen is insufficient, since the hydrogen flow rate is insufficient and no impure gas is generated, the temperature in the tank 21 is increased and the hydrogen flow rate is increased. In step S44, a heater-on command is output to the heating / cooling device 22.

  When the temperature T in the tank 21 is T <T2 and the supply amount of hydrogen is sufficient, the hydrogen flow rate increases with heating, is below the impure gas generation start temperature, and the supply amount of hydrogen is sufficient. Therefore, in order to maintain the temperature of the tank 21, a heater-off command is output to the heating / cooling device 22 in step S47.

  When the temperature T in the tank 21 is T2 ≦ T <T3, an overshoot is observed in the heating process, which is equal to or higher than the impure gas generation start temperature. In order to lower the temperature, a heater-off command is output to the heating / cooling device 22 in step S50. Since the hydrogen generation reaction is an endothermic reaction, the temperature in the tank 21 is lowered by maintaining the temperature in the tank 21.

  In the case of T3 ≦ T, overshoot is observed in the heating process, and the temperature becomes higher than the impure gas rapid increase temperature. Therefore, when further heated, ammonia which is an impure gas rapidly increases. In order to suppress this, a cooler-on command is output to the heating / cooling device 22 in step S52.

  A hydrogen generation system according to a fourth embodiment of the present invention includes a container containing a hydrogen storage material that generates a by-product gas in an amount dependent on temperature, temperature adjusting means for adjusting the temperature in the container, And a control means for controlling the temperature adjusting means based on the estimated amount, and the control means determines the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated. A data storage unit for storing the first data to be shown, a temperature measurement unit for measuring the temperature in the container, and a control unit for controlling the data based on the measurement result. It includes second data indicating the relationship between the temperature of the material 30 and the amount of hydrogen gas generated, and includes a hydrogen supply path for supplying hydrogen gas from the container to the outside, and the control means is supplied to the outside from the hydrogen supply path. Control using the amount of hydrogen gas as a control condition , Suppressing the generation of by-product gas, it is possible to provide a hydrogen generation system in which the amount of hydrogen required can be obtained. That is, when the relationship between the amount of by-product gas generated and the temperature of the hydrogen storage material is known, the concentration of by-product gas contained in the generated gas can be calculated by measuring the temperature of the hydrogen storage material. . For this reason, the control of the temperature adjusting means can be determined using the temperature of the hydrogen storage material as a parameter, and the concentration of the by-product gas contained in the generated gas can be reduced. Also, by using the excess or deficiency of the hydrogen supply amount in the judgment of the control means for controlling the temperature adjusting means, the use of the hydrogen generation system at a temperature with a low by-product gas concentration while obtaining the necessary hydrogen supply amount. Enable. Furthermore, by measuring the hydrogen supply amount, stable hydrogen can be supplied in a temperature range where the by-product gas concentration is lower.

  As in the first embodiment, the first data indicating the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated, and the second data indicating the relationship between the temperature of the hydrogen storage material and the amount of generated hydrogen gas. In order to obtain this data, the relationship between the temperature of the hydrogen storage material and the amount of by-product gas generated and the relationship between the temperature of the hydrogen storage material and the amount of hydrogen gas generated through experiments using a small amount of sample in advance. It is necessary to carry out the experiment to obtain.

  In the conventional method for judging only from the hydrogen supply amount, the operation of the hydrogen generation system in the temperature range where the by-product gas is generated cannot be prevented. However, according to the fourth embodiment of the present invention, the by-product is generated. The system is not operated in the temperature range where the gas is generated, and the concentration of the by-product gas contained in the generated hydrogen can be reduced to about 1/10 of the conventional one.

<Fifth Embodiment>
Next, a hydrogen generation system according to a fifth embodiment of the present invention will be described with reference to FIGS. Since the fuel cell system and the fuel cell vehicle are the same as those in the first embodiment, description thereof will be omitted. FIG. 13 is a principal block diagram of the HGS, and FIG. 14 shows a control flow P5 of the HGS. In the hydrogen generation system of the fifth embodiment, the determination of heating and cooling of the tank 21 is performed based on the hydrogen supply amount and impure gas concentration detected by the generated gas concentration meter 27 regardless of the measurement result by the thermometer 25. This is different from the first embodiment. Since other configurations are substantially the same as those in the first embodiment, the same reference numerals are given to the same components and the description thereof is omitted.

  The hydrogen generation system HGS includes a tank (container) 21 in which a hydrogen storage material 30 that generates a by-product gas depending on a temperature is accommodated, and a heating / cooling device (temperature adjustment means) that adjusts the temperature in the tank 21. 22 and a control means for estimating the amount of by-product gas generated in the tank 21 and controlling the heating / cooling device 22 based on the estimated amount. This control means includes a hydrogen generation control device HGC and a generated gas concentration meter (concentration measuring unit) 27 that measures the concentration of the by-product gas in the tank 21, and the hydrogen generation control device HGC performs control based on the measurement result. A CPU (control unit) 28 is provided. Further, a fuel supply system (hydrogen supply path) 2 for supplying hydrogen gas from the tank 21 to the outside is provided, and the control means performs control using the amount of hydrogen gas supplied from the fuel supply system 2 to the outside as a control condition. This will be described in more detail below.

  As shown in FIG. 13, the hydrogen generation control device HGC includes a central processing unit (CPU) 28 and a memory 29 as a peripheral device of the CPU 28, and the CPU 28 performs operations related to the control flow P <b> 5 shown in FIG. 14. The memory 29 stores programs and data necessary for these operations.

  The fuel cell control device FCC outputs control signals C1 to C3 corresponding to the operation state of the hydrogen generation system HGS and the vehicle, and appropriately controls the fuel supply system 2 including the hydrogen pump HP, the pressure reducing valve 2a, and the flow control valve 2b. Control.

The HGC issues a control signal to the heating / cooling device 22 according to the control map shown in Table 5.

  FIG. 14 shows a control flow P5 of the hydrogen generation system according to the fifth embodiment. The control flow P5 first reads out the control map shown in Table 5 in step S60, and proceeds to step S61.

  In step S 61, a heater-on command is issued to the heating / cooling device 22. When the predetermined time has passed, the process proceeds to the next step S62.

  In step S62, the concentration of the impure gas that is a by-product gas inside the tank 21 is measured by the generated gas concentration meter 27, and it is determined whether or not the impure gas is detected. If no impure gas is detected (NO), the process proceeds to step S63. If an impure gas is detected (YES), the process proceeds to the next step S68.

  In step S63, it is determined whether the supply amount of hydrogen is sufficient. If hydrogen is insufficient, the process proceeds to step S64. If hydrogen is sufficient, the process proceeds to step S66.

  In step S64, the control method <heating 4> is selected, and the process proceeds to step S65.

  In step S65, a heater-on command is output to the heating / cooling device 22.

In step S66, the control method <holding 3> is selected, and the process proceeds to step S67.
In step S67, a heater-off command is output to the heating / cooling device 22.

  In step S68, the concentration of the impurity gas in the tank 21 is measured by the generated gas concentration meter 27, and it is determined whether or not the impurity gas concentration Ci <1%. If Ci <1% (YES), the process proceeds to step S69. When Ci <1% is not satisfied (NO), that is, when 1% ≦ Ci, the process proceeds to the next step S71.

  In step S69, the control method <hold 2> is selected, and the process proceeds to step S70.

  In step S70, a heater-off command is output to the heating / cooling device 22.

  In step S71, the control method <cooling 1> is selected, and the process proceeds to step S72.

  In step S72, a cooler-on command is output to the heating / cooling device 22.

  That is, in the fifth embodiment, heating and cooling are determined based on the hydrogen supply amount and impure gas concentration detected by the generated gas concentration meter 27, and the generation of impure gas is suppressed. In step S <b> 61, the tank 21 is heated by the heating / cooling device 22 to generate hydrogen from the hydrogen storage material 30 stored in the tank 21.

  If the impure gas is not detected and the supply amount of hydrogen is insufficient, the hydrogen flow rate is insufficient and no impure gas is generated. Therefore, the temperature in the tank 21 is increased to increase the hydrogen flow rate. The heater-on command is output to the heating / cooling device 22 at.

  If no impure gas is detected and the supply amount of hydrogen is sufficient, the flow rate of hydrogen increases with heating, and the supply amount of hydrogen is sufficient, so that the temperature of the tank 21 is maintained. -Outputs an OFF command to the heating / cooling device 22.

  In step S62, when an impure gas is detected and its concentration is Ci <1%, overshoot is observed in the heating process, which is not less than the impure gas generation start temperature, but is not more than the impure gas rapid increase temperature. Therefore, in step S70, a heater-off command is output to the heating / cooling device 22. Since the hydrogen generation reaction is an endothermic reaction, the temperature in the tank 21 is lowered by maintaining the temperature in the tank 21.

  In step S68, when 1% ≦ Ci, overshoot is observed in the heating process, and the temperature becomes higher than the impure gas rapid increase temperature. In order to suppress this, a cooler-on command is output to the heating / cooling device 22 in step S72.

  A hydrogen generation system according to a fifth embodiment of the present invention includes a container containing a hydrogen storage material that generates a by-product gas in an amount dependent on temperature, temperature adjusting means for adjusting the temperature in the container, And a control means for controlling the temperature adjusting means based on the estimated amount, and the control means includes a concentration measuring unit for measuring the concentration of the by-product gas in the container, A control unit that performs control based on the measurement result, and further includes a hydrogen supply path that supplies hydrogen gas from the container to the outside, and the control unit controls the amount of hydrogen gas supplied from the hydrogen supply path to the outside. Since the control is performed as a condition, it is possible to provide a hydrogen generation system that suppresses the generation amount of by-product gas and obtains a necessary amount of hydrogen. That is, by measuring the concentration of the by-product gas, the container temperature adjusting means can be directly controlled. Further, by measuring the hydrogen supply amount, stable hydrogen can be supplied in a temperature range where the by-product gas concentration is lower.

  In the conventional method for judging from only the hydrogen supply amount, the operation of the hydrogen generation system in the temperature range where the by-product gas is generated cannot be prevented. However, according to the fifth embodiment of the present invention, the by-product is generated. The system is not operated in the temperature range where the gas is generated, and the concentration of the by-product gas contained in the generated hydrogen can be reduced to about 1/10 of the conventional one.

  Although the embodiment of the present invention has been described above, it should not be understood that the description and drawings that constitute part of the disclosure of the embodiment limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

1 is a schematic system diagram of a fuel cell system FCS according to a first embodiment. 1 is a side view of a fuel cell vehicle according to a first embodiment. It is a principal part block diagram of the hydrogen generation system which concerns on 1st Embodiment. It is a gas generation characteristic diagram concerning a 1st embodiment. It is a control flow of the hydrogen generation system which concerns on 1st Embodiment. It is a principal part block diagram of the hydrogen generation system which concerns on 2nd Embodiment. It is a control flow of the hydrogen generation system which concerns on 2nd Embodiment. It is a principal part block diagram of the hydrogen generation system which concerns on 3rd Embodiment. It is a gas generation characteristic diagram concerning a 3rd embodiment. It is a control flow of the hydrogen generation system which concerns on 3rd Embodiment. It is a principal part block diagram of the hydrogen generation system which concerns on 4th Embodiment. It is a control flow of the hydrogen generation system which concerns on 4th Embodiment. It is a principal part block diagram of the hydrogen generation system which concerns on 5th Embodiment. It is a control flow of the hydrogen generation system concerning a 5th embodiment.

Explanation of symbols

FCC fuel cell control device FCS fuel cell system HGC hydrogen generation control device HGS hydrogen generation system 1 fuel cell stack 2 fuel supply system (hydrogen supply path)
20 Hydrogen generator 21 Tank 22 Heating / cooling device (temperature adjusting means)
25 Thermometer (Temperature Measurement Unit)
27 Generated gas concentration meter (concentration measuring unit)
28 CPU
29 Memory 30 Hydrogen storage material 50 Fuel cell vehicle

Claims (12)

A container containing a hydrogen storage material that generates a by-product gas in a temperature-dependent amount;
Temperature adjusting means for adjusting the temperature in the container;
A hydrogen generation system comprising: a control unit that estimates a generation amount of a by-product gas in the container and controls the temperature adjustment unit based on the estimated amount.   The control means includes a data storage unit that stores first data indicating a relationship between the temperature of the hydrogen storage material and the generation amount of the by-product gas, a temperature measurement unit that measures the temperature in the container, The hydrogen generation system according to claim 1, further comprising a control unit that performs the control based on the measurement result.   2. The hydrogen generation according to claim 1, wherein the control unit includes a concentration measurement unit that measures a concentration of a by-product gas in the container, and a control unit that performs the control based on a result of the measurement. system.   3. The hydrogen generation system according to claim 2, wherein the first data includes second data indicating a relationship between a temperature of the hydrogen storage material and a generation amount of hydrogen gas.   A hydrogen supply path for supplying hydrogen gas from the container to the outside is provided, and the control means performs the control using a quantity of hydrogen gas supplied from the hydrogen supply path to the outside as a control condition. The hydrogen generation system according to any one of claims 1 to 4.   6. The hydrogen generation system according to claim 1, wherein the control unit performs control by estimating a generation amount of hydrogen gas.   The first data includes third data indicating a relationship between the temperature of the hydrogen storage material and the generation amount of the by-product gas having the lowest generation start temperature among the by-product gases, and the control means The hydrogen generation system according to any one of claims 2 to 6, wherein the control is performed using the third data as a control condition.   The said hydrogen storage material has as a main component the material which consists of a metal chosen from an alkali metal and an alkaline-earth metal element, nitrogen, and hydrogen, The Claim 1 thru | or 7 characterized by the above-mentioned. The hydrogen generation system described.   The said hydrogen storage material has as a main component the material which consists of a metal chosen from an alkali metal and an alkaline-earth metal element, boron, and hydrogen, The Claim 1 thru | or 7 characterized by the above-mentioned. The hydrogen generation system described.   The hydrogen generation system according to any one of claims 1 to 7, wherein the hydrogen storage material includes a compound mainly composed of nitrogen, boron, and hydrogen.   A fuel cell system using the hydrogen generation system according to any one of claims 1 to 10.   A fuel cell vehicle using the fuel cell system according to claim 11.

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