JP2008256143A - Hydrogen supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen supply device capable of reducing a variation of an odorant concentration on a flow passage of hydrogen added with the odorant. <P>SOLUTION: The hydrogen supply device is provided with an addition means for adding the odorant to hydrogen supplied to a hydrogen supply object, a plurality of buffer tanks for storing hydrogen added with the odorant and a control means for switching the connection state of the plurality of buffer tanks and the hydrogen supply object so that the hydrogen added with the odorant is supplied to the hydrogen supply object from one of the plurality of buffer tanks of which the odorant concentration is uniformized in a predetermined order. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hydrogen supply apparatus that supplies hydrogen to which a odorant is added to a hydrogen supply target.

Conventionally, depending on the odorant concentration in the hydrogen flowing through the odorant hydrogen circulation path including the hydrogen supply target (for example, a fuel cell), hydrogen containing a high concentration odorant is added to pure hydrogen released from the tank. There has been proposed a hydrogen supply device that controls the concentration of an odorant in hydrogen supplied to a hydrogen supply target by supplying the odorant hydrogen circulation path (see Patent Document 1).
JP 2004-111167 A JP 2002-29701 A

  However, in the technique described in Patent Document 1, since the mixing amount of the odorant-mixed hydrogen with respect to pure hydrogen is not taken into consideration, the concentration of the odorant in the hydrogen supplied to the odorant hydrogen circulation path varies. There was a risk of it.

  The objective of this invention is providing the hydrogen supply apparatus which can reduce the variation in the odorant density | concentration in the flow path of hydrogen to which the odorant was added.

  Another object of the present invention is to provide a hydrogen supply device capable of reducing the supply amount of the odorant.

  The present invention employs the following configuration in order to solve the above-described problems.

That is, the first aspect of the present invention is an addition means for adding an odorant to hydrogen to be supplied to a hydrogen supply target;
A plurality of buffer tanks each storing odorant-added hydrogen to which an odorant is added;
In a predetermined order, the plurality of the odorant concentrations are uniformized so that the hydrogen to which the odorant is added is supplied from any one of the plurality of buffer tanks having a uniform state to the hydrogen supply target. A hydrogen supply apparatus comprising a control means for switching a connection state between a buffer tank and the hydrogen supply target.

  According to the present invention, hydrogen to which a odorant is added (odorant-added hydrogen) is stored (filled) in a plurality of buffer tanks. The odorant in the stored odorant-added hydrogen diffuses in the buffer tank, and eventually the odorant concentration in the buffer tank becomes uniform. The odorant-added hydrogen having a uniform odorant concentration is supplied to the hydrogen supply target. The control means uses a plurality of buffer tanks in a predetermined order, and supplies the odorant-added hydrogen having a uniform odorant concentration from any one of the plurality of buffer tanks. And the connection state between the plurality of buffer tanks. Thereby, the variation in the concentration of the odorant on the flow path of the odorant-added hydrogen can be reduced, and the effect of the odorant can be sufficiently exhibited.

  Further, according to the present invention, since the supply amount of the odorant can be determined according to the capacity of each buffer tank, the concentration of the odorant when uniformized in the buffer tank is the effect of the odorant. As long as the odorant can be sufficiently exhibited (the user can sense the odor of the odorant), the supply amount of the odorant can be reduced.

  Further, according to the present invention, the control means monitors the remaining amount of the odorant-added hydrogen in the buffer tank that is connected to the hydrogen supply target and is supplying the odorant-added hydrogen, and the remaining amount falls below a predetermined value. In this case, the connection state between the buffer tank and the hydrogen supply target may be disconnected, and the buffer tank to be used next and the hydrogen supply target may be connected. Furthermore, the buffer tank in which the connection state is disconnected can be configured to be filled with odorant-added hydrogen to which the odorant is added by the adding means.

  Preferably, the control means in the first aspect of the present invention includes means for storing the number of times of switching the connection state between the plurality of buffer tanks and the hydrogen supply target, and when the number of times of switching reaches a predetermined value. A signal indicating the deterioration of the adsorbent that adsorbs the odorant in the odorant-added hydrogen discharged from the hydrogen supply target is output.

  In this way, it is possible to notify the user of the deterioration of the adsorbent.

Further, the second aspect of the present invention is an addition means for adding an odorant to hydrogen to be supplied to a hydrogen supply target;
A buffer tank for storing odorant-added hydrogen to which an odorant is added;
A stirrer for stirring the odorant-added hydrogen in the buffer tank;
Addition of odorant per unit time under the situation where the odorant-added hydrogen is supplied from the buffer tank to the hydrogen supply target through the hydrogen supply path while the buffer tank is filled with odorant-added hydrogen. And a control unit that controls a stirring ability of the stirrer according to a filling amount of hydrogen.

  Even with such a configuration, the odorant concentration in the odorant-added hydrogen can be made uniform in a single buffer tank, and the odorant-added hydrogen on the flow path can be made uniform. It becomes possible to reduce the variation of the odorant concentration.

  ADVANTAGE OF THE INVENTION According to this invention, the variation in the odorant density | concentration on the flow path of hydrogen to which the odorant was added can be reduced. Moreover, according to this invention, the addition amount of the odorant with respect to hydrogen can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The configuration of the embodiment is an exemplification, and the present invention is not limited to the configuration of the embodiment.

Embodiment 1
<Configuration of fuel cell system>
FIG. 1 is a diagram showing a configuration example of a fuel cell system to which a hydrogen supply device according to the present invention is applied. The fuel cell system shown in FIG. 1 is mounted on a vehicle. However, the hydrogen supply device according to the present invention is also applicable to a stationary fuel cell system. The fuel cell (FC) 1 shown in FIG. 1 will be described as a polymer electrolyte fuel cell (PEFC). But the fuel cell which can apply this invention is not restricted to PEFC. The present invention can also be applied to hydrogen supply objects other than fuel cells.

  In FIG. 1, a fuel cell 1 as a hydrogen supply target has a cell stack in which a plurality of cells are stacked. Each cell includes a solid polymer electrolyte membrane, a fuel electrode (anode) and an air electrode (oxidizer electrode: cathode) that sandwich the solid polymer electrolyte membrane from both sides, and a fuel electrode side separator and air that sandwich the fuel electrode and air electrode. It consists of a pole-side separator.

  The fuel electrode has a diffusion layer and a catalyst layer. Fuel containing hydrogen, such as hydrogen gas or hydrogen rich gas, is supplied to the fuel electrode by a fuel supply system. The fuel supplied to the fuel electrode is diffused in the diffusion layer and reaches the catalyst layer. In the catalyst layer, hydrogen is separated into protons (hydrogen ions) and electrons. Hydrogen ions move to the air electrode through the solid polymer electrolyte membrane, and electrons move to the air electrode through an external circuit.

  On the other hand, the air electrode has a diffusion layer and a catalyst layer, and an oxidant gas such as air is supplied to the air electrode by an oxidant supply system. The oxidant gas supplied to the air electrode is diffused in the diffusion layer and reaches the catalyst layer. In the catalyst layer, water is generated by a reaction between the oxidant gas, hydrogen ions that have reached the air electrode through the solid polymer electrolyte membrane, and electrons that have reached the air electrode through the external circuit. The electrons passing through the external circuit during the reaction at the fuel electrode and the air electrode are used as electric power for a load (not shown) connected between both terminals of the cell stack of the fuel cell 1.

  A fuel supply / discharge system for supplying fuel and an oxidant supply / discharge system for supplying and discharging oxidant are connected to the fuel cell 1. FIG. 1 shows a fuel supply / discharge system, which is configured as follows.

  The fuel supply system has a hydrogen supply path that supplies hydrogen released from a hydrogen tank 2 storing hydrogen storage alloy (MH), liquid hydrogen, or high-pressure hydrogen gas to a fuel inlet provided in the fuel cell 1. .

  The hydrogen supply path is configured between the hydrogen tank 2 and the fuel inlet of the fuel cell 1 as follows. That is, the hydrogen supply path includes a main flow path M1 extending from the hydrogen tank 2, branch paths D1 and D2 in which the first main flow path M1 branches in two directions, a junction of the branch paths D1 and D2, and fuel. The main flow path M2 connecting the inlet and the branch path D3 branched from the middle of the main flow path M1 and coupled (joined) to the main flow path M1 again.

  A pressure regulating valve (regulator) 3 for regulating the hydrogen released from the hydrogen tank 2 and a flow meter (HFM) 4 for measuring the flow rate of the hydrogen released from the pressure regulating valve 3 are arranged on the main flow path M1. Yes.

An odorant supply device 5 for adding a predetermined odorant to the hydrogen released from the pressure regulating valve 3 is provided on the branch path D3. The odorant supply device 5 includes a pump 6 for introducing hydrogen released from the pressure regulating valve 3 into the branch path D3, and an addition means for adding an odorant to the hydrogen released from the pump 6. The odorant addition unit 7 and hydrogen to which the odorant discharged from the odorant addition unit 7 is added (hereinafter referred to as “odorant addition hydrogen”. Also, hydrogen to which no odorant is added is referred to as hydrogen. And a check valve 8 for preventing the backflow of odorant-added hydrogen and pure hydrogen (referred to as “hydrogen”).

  A first buffer tank 9A capable of temporarily storing hydrogen from the main flow path M1 is provided on the branch path D1. At both ends of the buffer tank 9A, a valve 10A for introducing / stopping introduction of hydrogen into the buffer tank 9A and a valve 10B for carrying out release / release stop of hydrogen from the buffer tank 9A are provided. .

Similar to the branch path D1, hydrogen from the main flow path M1 is temporarily stored on the branch path D2.
A second buffer tank 9B is provided. At both ends of the buffer tank 9B, a valve 10C for introducing / stopping introduction of hydrogen into the buffer tank 9B and a valve 10D for releasing / stopping hydrogen from the buffer tank 9B are provided. .

  The valves 10A, 10B, 10C, and 10D are switching valves that switch between an open state and a closed state, and can be configured using, for example, an electromagnetic valve.

  On the main flow path M2, a flow meter 11 for measuring the flow rate of hydrogen released from one of the buffer tanks 9A and 9B and a flow rate adjusting valve 12 for adjusting the flow rate of hydrogen supplied to the fuel cell 1 are provided. ing.

  The components provided between the hydrogen tank 2 and the fuel inlet of the fuel cell 1 as described above correspond to the hydrogen supply device according to the present invention.

On the other hand, the fuel discharge system is configured as follows. That is, the fuel discharge system is connected to the fuel outlet of the fuel cell 1, the pipe 14 through which hydrogen (hydrogen offgas) discharged from the fuel cell 1 flows, and the hydrogen offgas discharged to the pipe 14 flows again through the branch pipe 15. A circulation pump 16 for returning to the path M2, a purge valve 17 for discharging the hydrogen off-gas in the pipe 14 to the outside without returning to the branch pipe 15, and an odorant in the hydrogen off-gas passing through the purge valve 17 An adsorber 18 for removing and a diluter 19 for diluting the hydrogen off-gas that has passed through the adsorber 18 and releasing (exhausting) it into the atmosphere are provided. The adsorber 18 contains an adsorbent (for example, activated carbon) for adsorbing the odorant.

  The fuel cell system according to the embodiment includes an odorant supply device 5 that supplies (adds) an odorant to pure hydrogen supplied from the hydrogen tank 2 as one of the features of the hydrogen supply device according to the present invention. . The odorant addition unit 7 of the odorant supply device 5 employs, for example, the following configuration in order to add the odorant to the pure hydrogen guided from the main channel M1 to the branch channel D3 by the pump 6. Can do.

  (A) including a flow path through which pure hydrogen flows and a container containing a solid, liquid, or gel-like odorant, and the pure hydrogen flowing through the flow path comes into contact with the odorant to vaporize the odorant. Mix with pure hydrogen.

(B) a flow path through which pure hydrogen flows, a liquid odorant container, supply means (for example, a solenoid valve) for supplying odorant droplets in the odorant container to the flow path, or in the flow path Injection device that injects mist-like odorant (
And an odorant in the form of droplets or mist is vaporized by the flow of pure hydrogen and mixed with pure hydrogen.

  (C) Furthermore, an adjusting means for adjusting the supply amount (addition amount) of the odorant can be added to the above-described (A) or (B). The supply amount of the odorant can be determined according to the flow rate of pure hydrogen released from the pressure regulating valve 3, for example. The adjusting means for (A) adjusts the contact amount of pure hydrogen with the odorant according to the amount of pure hydrogen. The adjusting means relating to (B) adjusts the supply amount of droplets and sprays according to the amount of pure hydrogen.

  However, in the first embodiment, the odorant addition unit 7 is configured such that a predetermined amount of odorant based on the capacity of each buffer tank 9A and 9B is added to pure hydrogen. In other words, a predetermined amount of pure hydrogen corresponding to the capacity is supplied to each of the buffer tanks 9A and 9B, while an odorant corresponding to the predetermined amount of pure hydrogen is added to the pure hydrogen. The adding amount adjusting means is configured as described above.

  The odorant-added hydrogen from the odorant addition unit 7 and the pure hydrogen from the pressure regulating valve 3 merge at the junction of the main flow path M1 and the branch path D3 and head toward the branch paths D1 and D2. It has become.

In addition, as another feature of the present invention, the fuel cell system according to the embodiment temporarily stores odorant-added hydrogen in order to make the odorant concentration distribution in the odorant-added hydrogen uniform. Two or more buffer tanks (in the embodiment, buffer tanks 9A and 9B). Then, the odorant-added hydrogen is released from any one of the two or more buffer tanks in a predetermined order toward the fuel cell 1 (hydrogen supply target) (one of the buffer tanks and the fuel cell 1 are Connected by a hydrogen supply channel). In the example shown in FIG. 1, the odorant-added hydrogen is alternately discharged from the buffer tanks 9A and 9B.

The above-described operation is performed by the valves 10A, 10 provided at both ends of the buffer tanks 9A and 9B.
This is realized by controlling the opening / closing operation of B, 10C and 10D. The fuel cell system (hydrogen supply device) described above includes an ECU (Electronic Control Unit) 20 which is a control device (control means). The ECU 20 includes a processor such as a CPU, a program, a storage device (memory, nonvolatile memory, etc.) that stores data used when the program is executed, an input / output interface (I / O), and the like.

  The ECU 20 controls the operation of the fuel supply / discharge system by the processor executing a program stored in the storage device. That is, the ECU 20 controls the pressure regulating valve 3, the odorant supply device 5 (pump 6, odorant addition unit 7), valves 10A to 10D, the flow rate adjustment valve 12, the circulation pump 16, the purge valve 17 and the like shown in FIG. To control the operation.

  When the program is executed, the ECU 20 measures the data stored in advance in the storage device, the flow rate of the odorant-added hydrogen input from the flow meter 11, and an ammeter (not shown) connected to the fuel cell 1. The power generation amount of the fuel cell 1 obtained from the power generation current (FC current) of the fuel cell 1 is used. The ECU 20 is configured to receive a signal indicating the hydrogen flow rate from the flow meter 11 and a signal indicating the FC current.

  Next, an operation example (control example of the ECU 20) when supplying the odorant-added hydrogen to the fuel cell 1 in the fuel cell system shown in FIG. 1 will be described. FIG. 2 is a flowchart showing an example of hydrogen supply processing (including buffer tank switching control) by the ECU 20.

  Before the fuel cell 1 is activated, the following pretreatment (odorant-added hydrogen filling treatment) is performed. The pretreatment is a process for filling at least one of the two or more buffer tanks with the odorant-added hydrogen so that the odorant-added hydrogen having a uniform odorant concentration is supplied to the fuel cell 1. It is.

  When the pre-processing is started, the ECU 20 causes the pure hydrogen adjusted by the pressure adjusting valve 3 to be sent from the hydrogen tank 2 to the main flow path M1. At this time, the ECU 20 drives the pump 6 to draw pure hydrogen into the branch path D3, and joins the odorant-added hydrogen added with the odorant in the odorant addition unit 7 to the main channel M1.

On the other hand, regarding the branch paths D1 and D2, the ECU 20 selects one of the valves 10A and 10C (
For example, the valve 10A) is opened and the other (eg, valve 10C) is closed. At this time, the valves 10B and 10D are closed. Thus, the odorant-added hydrogen is stored (filled) in the buffer tank 9A through the valve 10A.

  When the buffer tank 9A is filled with a predetermined amount of odorant-added hydrogen, the ECU 20 closes the valve 10A and opens the valve 10C. The opening / closing timing of the valves 10A and 10C can be determined by the ECU 20 based on the flow rate of pure hydrogen measured by the flow meter (HFM) 4 disposed at the subsequent stage of the pressure regulating valve 3. Further, the ECU 20 controls the operation of the odorant supply device 5 so that the odorant supply device 5 supplies a predetermined amount of odorant before switching from the valve 10A to the valve 10C.

By opening the valve 10C, the buffer tank 9B is also filled with the odorant-added hydrogen in the same manner as the filling process for the buffer tank 9A. When a predetermined amount of odorant-added hydrogen is filled in the buffer tank 9B, the valve 10C is closed.

  The odorant in the odorant-added hydrogen charged in the buffer tanks 9A and 9B diffuses in the buffer tanks 9A and 9B over time, and eventually the concentration of the odorant in the buffer tanks 9A and 9B. The distribution is almost uniform (uniform). The time (residence time) required for the concentration distribution of the odorant in the buffer tanks 9A and 9B to be substantially uniform can be obtained in advance by experiments or the like. During such a residence time, the ECU 20 maintains the state where the odorant-added hydrogen stays in the buffer tanks 9A and 9B by closing the valves 10A to 10D at both ends of the buffer tanks 9A and 9B.

  In order to shorten the residence time, a stirrer may be disposed in the buffer tanks 9A and 9B, and the odorant-added hydrogen in the buffer tanks 9A and 9B may be stirred by the operation of the stirrer. The operation control of the stirrer can be executed by the ECU 20.

When the odorant concentration distribution of the odorant-added hydrogen in the buffer tank 9A is made uniform, the odorant-added hydrogen can be supplied from the buffer tank 9A to the fuel cell 1. Accordingly, the preprocessing ends when the residence time has elapsed after the valves 10A and 10B at both ends of the buffer tank 9A are closed. However, it is possible to continuously fill the remaining buffer tank (buffer tank 9B) with the odorant-added hydrogen even after the completion of such pretreatment.

  The ECU 20 is configured to receive a start signal and a stop signal for the fuel cell 1 from other devices in the vehicle. The ECU 20 starts the hydrogen supply process for the fuel cell 1 if the preprocessing is completed when the activation signal is received. If the pretreatment is not finished, the hydrogen supply treatment is started after the pretreatment is finished. The flowchart of FIG. 2 shows an example of the hydrogen supply process.

  In FIG. 2, when the hydrogen supply process is started (START), the ECU 20 turns on the circulation pump 16 (purge valve 17: closed) and switches the valve 10B to open (step S01), thereby the buffer tank 9A. Supply of the odorant-added hydrogen having a uniform odorant concentration therein to the fuel cell 1 is started.

  Subsequently, the ECU 20 determines whether or not the remaining amount of pure hydrogen in the buffer tank 9A is less than a predetermined threshold (predetermined value) (step S02). If the remaining amount is equal to or greater than the predetermined value (S102: NO), the process returns to step S01. If the remaining amount is less than the predetermined value (S102: YES), the process proceeds to step S03.

  In step S02, the ECU 20 controls the flow rate of the odorant-added hydrogen released from the flow rate adjustment valve 12 according to the power generation amount of the fuel cell 1, and monitors the remaining amount based on the control result. Here, there is a proportional relationship between the FC current (power generation amount) and the hydrogen consumption amount in the fuel cell 1, and the power generation amount can be regarded as the hydrogen consumption amount. The ECU 20 controls the flow rate adjustment valve 12 based on the FC current so that the amount of odorant-added hydrogen required by the fuel cell 1 for power generation is supplied.

  Further, the ECU 20 controls the opening / closing operation of the purge valve 17 as necessary. When the purge valve 17 is closed and the circulation pump 16 is in operation, the odorant-added hydrogen released from the flow control valve 12 passes through the main flow path M2, the fuel cell 1 (anode), the pipe 14, the branch pipe 15, and the circulation pump 16. It will be in the state which circulates through the circulation path which returns to the main flow path M2 again.

In contrast, in the open state of the purge valve 17, the odorant-added hydrogen (hydrogen offgas) discharged to the pipe 14 passes through the purge valve 17 and reaches the adsorber 18 through the pipe 13. Adsorber 1
In FIG. 8, the odorant in the hydrogen off-gas is adsorbed and recovered by the adsorbent disposed inside the adsorber 18. The hydrogen off-gas from which the odorant has been removed by the adsorber 18 is diluted by the diluter 19 and then discharged into the atmosphere.

When supplying the odorant-added hydrogen, the flow meter 11 measures the flow rate of the odorant-added hydrogen passing through itself and notifies the ECU 20 of it. The ECU 20 determines the cumulative value of the flow rate notified from the flow meter 11 (
(Integrated value) is stored in the storage device, and when this accumulated value falls below a predetermined value, it is determined that the remaining amount of pure hydrogen in the buffer tank 9A has become less than the predetermined value (S02: YES).

  At this time, the ECU 20 determines whether or not the valve 10C is in a closed state. If it is in the open state, the process proceeds to step S11. If it is in the closed state, the process proceeds to step S04. In step S04, the ECU 20 switches the valve 10B to close and switches the valve 10D to open. As a result, the odorant-added hydrogen in the buffer tank 9B is supplied to the fuel cell 1.

Subsequently, the ECU 20 switches the valve 10A of the buffer tank 9A to an open state (step S05). Subsequently, the ECU 20 resets the accumulated value of the flow rate on the storage device, and starts monitoring the remaining amount of pure hydrogen in the buffer tank 9B (step S06). That is, the same processing as step S02 is performed for the buffer tank 9B.

In step S06, if the remaining amount in the buffer tank 9B is not less than the predetermined value (S06: NO), it is determined whether the filling amount of the odorant added hydrogen in the buffer tank 9A has reached the predetermined value. (Step S07). At this time, if the filling amount has reached a predetermined value (S
(07: YES) After closing the valve 10A (step S08), the ECU 20 returns the process to step S06. On the other hand, if the filling amount has not reached the predetermined value (S07: NO), the process returns to step S06.

  In this way, while the odorant-added hydrogen is being released from the buffer tank 9B, the buffer tank 9A is refilled with the odorant-added hydrogen. When the remaining amount of the buffer tank 9B becomes less than the predetermined value (S06: YES), the ECU 20 opens the valve 10B and closes the valve 10D (step S09).

  Thereby, the supply of the odorant-added hydrogen from the buffer tank 9A is started again. At the start of step S09, the odorant-added hydrogen is filled into the buffer tank 9A so that the odorant concentration in the buffer tank 9A is substantially uniform.

Subsequent to step S09, the ECU 20 opens the valve 10C (step S10), performs the filling process of the odorant added hydrogen to the buffer tank 9B, and monitors the filling amount (step S).
11). At this time, if the filling amount does not reach the predetermined value (S11: NO), the process is returned to step S02, and the remaining amount of the buffer tank 9A is checked. Then, the loop process of steps S11 → S02 → S03 → S11 is executed until the filling amount into the buffer tank 9B reaches a predetermined value.

  When the filling amount into the buffer tank 9B reaches a predetermined value (S11: YES), the ECU 20 closes the valve 10C (S12) and returns the process to step S02. Thereafter, if a determination of YES is made in step S02, the valve 10C is closed at that time, so the process proceeds from step S03 to S04. Thereafter, the processing after step S04 is repeated until the power generation of the fuel cell 1 is stopped.

  In this way, the odorant-added hydrogen is alternately supplied from the buffer tanks 9A and 9B to the fuel cell 1 during power generation of the fuel cell 1.

  When the ECU 20 receives the stop signal of the fuel cell 1, the ECU 20 stops the hydrogen supply process shown in FIG. 2 and performs the end process of the hydrogen supply process. In the termination process, the ECU 20 closes the valves 10A to 10B and terminates the hydrogen supply process.

  At this time, both the buffer tanks 9A and 9B can be filled with a predetermined amount of odorant-added hydrogen. That is, for the buffer tank that was in use at the time of receiving the stop signal, the amount of odorant-added hydrogen to be filled is determined from the remaining amount, and that amount of odorant-added hydrogen is filled. In addition, the buffer tank that was being filled at the time of receiving the stop signal is continuously filled until a predetermined amount is reached.

In this way, when the fuel cell 1 is stopped, both the buffer tanks 9A and 9B can be filled with the odorant-added hydrogen. In other words, when the fuel cell 1 is started (
When the ECU 20 receives the start signal of the fuel cell 1, the hydrogen supply process can be immediately started.

  Alternatively, the remaining amount of the buffer tank that is in use and the filling amount of the buffer tank that is being filled are stored during the termination process, and each buffer is stored based on the remaining amount and the filling amount described above when the fuel cell 1 is started up next time. The tank may be filled.

Further, since the amount of the odorant in the odorant-added hydrogen filled in the buffer tanks 9A and 9B can be determined in advance, the ECU 20 stores the number of times of switching between the buffer tanks 9A and 9B. The alarm signal indicating the life (deterioration) of the adsorbent is output to the notification device 21 when the number of times of switching reaches a predetermined value, and the notification device 21 outputs sound, light, image display, vibration, etc. And by combining these, it is possible to notify the user of an alarm indicating the life (deterioration) of the adsorbent. Thus, the user can appropriately know the replacement time of the adsorbent.

  According to the fuel cell system (hydrogen supply device) according to the first embodiment described above, the odorant-added hydrogen in which the odorant is added to pure hydrogen by the odorant supply device 5 (addition means) is stored in a plurality of buffers. The tanks (9A and 9B) are filled (stored), and the pure hydrogen and the odorant are sufficiently mixed in the buffer tanks 9A and 9B to make the odorant concentration uniform.

Then, the connection state between the plurality of buffer tanks and the fuel cell 1 is valved so that one of the plurality of buffer tanks having a uniform odorant concentration and the fuel cell 1 are connected by the hydrogen supply path. Switching through the control of 10B and 10D. Thus, the odorant-added hydrogen having a uniform odorant concentration is supplied from the plurality of buffer tanks to the fuel cell 1 in a predetermined order (alternately in this embodiment).

  As a result, the odorant-added hydrogen having a uniform odorant concentration is provided in the odorant-added hydrogen flow path (hydrogen supply path: for example, the above-described circulation path) located downstream of the buffer tanks 9A and 9B. Will be in a state of flowing. Further, the odorant-added hydrogen having a uniform odorant concentration flows through the pipe 13 constituting the hydrogen discharge path. In this way, it is possible to provide an environment where the odorant concentration variation in the odorant-added hydrogen can be reduced and the effect of the odorant can be sufficiently exerted.

Further, according to the fuel cell system of the first embodiment, the odorant-added hydrogen having a desired odorant concentration uniformized in the buffer tanks 9A and 9B is produced. It depends on the amount of hydrogen that can be filled in 9B, that is, the capacity of the buffer tanks 9A and 9B. In view of this, as long as the odorant concentration when uniformized can sufficiently exert the effect as the odorant, the amount of odorant added per buffer tank capacity can be reduced.

  From the viewpoint of determining the amount of odorant added per buffer tank capacity, it is desirable that both buffer tanks 9A and 9B (a plurality of buffer tanks) have the same capacity. However, having the same capacity is not an essential requirement of the present invention.

  In the case where three or more buffer tanks are provided instead of the configuration of the first embodiment, a predetermined use order (order pattern) for the three or more buffer tanks is determined in advance. During power generation, the ECU 20 repeatedly performs control to supply the odorant-added hydrogen in a uniform state from any one of the three or more buffer tanks to the fuel cell 1 according to the order pattern. Note that odorant-added hydrogen with a uniform odorant concentration is desired for the buffer tank to be used next before the remaining amount of odorant-added hydrogen in the buffer tank currently in use is less than a predetermined value. The order pattern can be arbitrarily determined regardless of the arrangement of the three or more buffer tanks as long as it can be filled with the amount of the buffer tank.

[Embodiment 2]
Next, Embodiment 2 of the present invention will be described. FIG. 3 is a diagram showing a fuel cell system according to the second embodiment, which is different from the fuel cell system according to the first embodiment in the following points.

  That is, in Embodiment 2, it has the main flow path M and the branch path D where the odorant supply apparatus 5 is arrange | positioned as a hydrogen supply path. Further, the flow meter 4 is omitted, and only one buffer tank 9A is provided in the main flow path M. A stirrer 23 is disposed in the buffer tank 9A. The stirrer 23 has, for example, rotating blades and is operated by drive control of the motor 24 by the ECU 20. Further, the operation control by the ECU 20 is different. Except for the above configuration, the configuration of the second embodiment is substantially the same as the configuration of the first embodiment.

  Also in the second embodiment, the same pretreatment as in the first embodiment is performed, and the buffer tank 9A is filled with a predetermined amount of odorant-added hydrogen. Under such circumstances, when an activation signal of the fuel cell 1 is input to the ECU 20, the ECU 20 starts a hydrogen supply process.

FIG. 4 is an explanatory diagram of a hydrogen supply process in the second embodiment. In FIG. 4, when the hydrogen supply process is started, the ECU 20 closes the purge valve 17, operates the circulation pump 16, opens the valve 10 </ b> B, and supplies the odorant-added hydrogen to the fuel cell via the flow rate adjustment valve 12. Supply to 1 (
Step S101).

Next, the ECU 20 gives a control signal to the motor 24 to operate the stirrer 23 (step S102).

  Next, the ECU 20 opens the valve 10A and operates the odorant supply device 5 so that the odorant-added hydrogen is filled in the buffer tank 9A (step S103).

Next, the ECU 20 controls the amount of odorant to be added to pure hydrogen, that is, the amount of odorant supplied based on the amount of hydrogen consumed in the fuel cell 1 (step S104). As described in the first embodiment, the hydrogen consumption is determined based on the integrated value of the odorant-added hydrogen flow rate that has passed through the flow meter 11 or the integrated value of the power generation amount of the fuel cell 1 obtained from the FC current or the like. Is done. The ECU 20 controls the pressure regulating valve 3 in accordance with the amount of hydrogen consumed to adjust the amount of pure hydrogen released (supply amount). In accordance with this, the ECU 20 controls the odorant supply device 5 so that the odorant corresponding to the consumption amount of hydrogen is added to pure hydrogen (the odorant is supplied).

  For example, if the hydrogen consumption per unit time (the integrated value of the flow rate or the power generation amount) exceeds a predetermined value, the ECU 20 increases the amount of pure hydrogen released from the pressure regulating valve 3 and supplies the odorant. Increase the amount. Further, when the hydrogen consumption per unit time is less than a predetermined value, the ECU 20 reduces the amount of pure hydrogen released from the pressure regulating valve 3 and the amount of odorant supplied. Here, the predetermined value for the supply amount increase determination and the predetermined value for the supply amount decrease determination may be the same or different.

Moreover, ECU20 controls the rotation speed of the stirrer 23 according to the flow volume of the odorant addition hydrogen measured with the flowmeter 11 (step S105). That is, when the amount of hydrogen consumed in the fuel cell 1 increases and the amount of odorant-added hydrogen supplied from the buffer tank 9A to the fuel cell 1 increases, the amount of odorant-added hydrogen to be filled into the buffer tank 9A. Also rises. In other words, the filling speed of the buffer tank 9A (the filling amount of the odorant-added hydrogen into the buffer tank 9A per unit time) increases. At this time, if the rotation speed of the stirrer 23 is constant, the odorant-added hydrogen in a state where the odorant concentration is not sufficiently uniform may be released from the valve 10B.

  For this reason, ECU20 controls the capability of a stirrer according to the filling amount of odorant addition hydrogen per unit time. For example, the ECU 20 increases the rotational speed of the stirrer 23 in accordance with the increase in the flow rate of the odorant-added hydrogen in the flow meter 11, and decreases the rotational speed of the stirrer 23 in accordance with the decrease in the flow rate of the odorant-added hydrogen. Thus, drive control of the motor 24 (rotational speed control of the stirrer 23) is performed.

The ECU 20 determines whether power generation of the fuel cell 1 is stopped, that is, whether a stop signal is received (step S106). At this time, when the power generation is not stopped (S10
6: NO), the process returns to step S104. On the other hand, when the power generation is stopped (S106: YES), the valves 10A and 10B are closed (step S107), and the stirrer 23 is stopped (step S108). Note that the ECU 20 may be configured to fill the buffer tank 9A with a predetermined amount of odorant-added hydrogen before closing the valve 10A.

  According to the second embodiment, as in the first embodiment, the odorant-added hydrogen having a uniform odorant concentration in hydrogen can be supplied to the fuel cell 1, and the odorant downstream of the valve 10B. The flow path of the added hydrogen can be in a state where odorant-added hydrogen having a uniform odorant concentration flows. Thereby, the effect of the odorant can be sufficiently exhibited.

Further, the stirrer 23 is disposed in the buffer tank 9A, and the odorant-added hydrogen is supplied to the fuel cell 1 by controlling the rotation speed of the stirrer 23 according to the supply amount (filling speed) of the odorant-added hydrogen. However, the odorant concentration can be made uniform in the buffer tank 9A. Moreover, waste of electric power can be suppressed by reducing the rotation speed when the filling speed is low.

FIG. 1 is an explanatory diagram showing a configuration example of a fuel cell system to which a hydrogen supply apparatus according to Embodiment 1 of the present invention can be applied. FIG. 2 is a flowchart showing a hydrogen supply process (control example of ECU) in the fuel cell system shown in FIG. FIG. 3 is a diagram showing a configuration example of a fuel cell system to which the hydrogen supply apparatus according to Embodiment 2 of the present invention can be applied. FIG. 4 is a flowchart showing a hydrogen supply process (control example of ECU) in the fuel cell system shown in FIG.

Explanation of symbols

M1, M2, M ... main flow paths D1, D2, D3, D ... branch 1 ... fuel cell 2 ... hydrogen tank 3 ... pressure regulator (regulator)
DESCRIPTION OF SYMBOLS 5 ... Odorant supply apparatus 6 ... Pump 7 ... Odorant addition part 8 ... Check valve 9A, 9B ... Buffer tank 10A, 10B, 10C, 10D ... Valve 11 ... Flow meter 12 ... Flow rate adjustment valves 13 and 14 ... Pipe 15 ... Branch pipe 16 ... Circulation pump 17 ... Purge valve 18 ... Adsorber 19 ... Diluter 20 ... ECU
21 ... Notification device 23 ... Stirrer 24 ... Motor

Claims (3)

An adding means for adding an odorant to hydrogen to be supplied to a hydrogen supply target;
A plurality of buffer tanks each storing odorant-added hydrogen to which an odorant is added;
In a predetermined order, the plurality of the odorant concentrations are uniformized so that the hydrogen to which the odorant is added is supplied from any one of the plurality of buffer tanks having a uniform state to the hydrogen supply target. A hydrogen supply device comprising a control means for switching a connection state between a buffer tank and the hydrogen supply target. The control means includes means for storing the number of times of switching of the connection state between the plurality of buffer tanks and the hydrogen supply target, and when the number of times of switching reaches a predetermined value, the control unit discharged from the hydrogen supply target. The hydrogen supply device according to claim 1, wherein a signal indicating deterioration of an adsorbent that adsorbs the odorant in the odorant-added hydrogen is output. An adding means for adding an odorant to hydrogen to be supplied to a hydrogen supply target;
A buffer tank for storing odorant-added hydrogen to which an odorant is added;
A stirrer for stirring the odorant-added hydrogen in the buffer tank;
Addition of odorant per unit time under the situation where the odorant-added hydrogen is supplied from the buffer tank to the hydrogen supply target through the hydrogen supply path while the buffer tank is filled with odorant-added hydrogen. A hydrogen supply device comprising: control means for controlling the stirring capacity of the stirrer according to the filling amount of hydrogen.

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