JP5340611B2 - Hydrogen generator and fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen generating device capable of appropriately preventing a trouble caused by the deviation of a ratio between a water molecule and a raw material (carbon atom number) supplied to a reforming device and having an excellent reliability and durability. <P>SOLUTION: The hydrogen generating device 50A is provided with the reforming device 13 for generating a hydrogen-containing gas by a reforming reaction by using the raw material and the water, a raw material supplying device 17 for supplying the raw material to the reforming device 13, a flow rate measuring device 18 for measuring the flow rate of the raw material supplied to the reforming device, a water supplying device 19 for supplying the water to the reforming device 13 and a controlling device 30A, and the controlling device 30A performs a feedback controlling of a working amount of the raw material supplying device 17 based on a detected value of the flow rate measuring device 18 and also performs the supply abnormality information of the water or the supply stopping of the raw material to the reforming device 13 based on the working amount of the raw material supplying device 17 after the start of the water supply to the reforming device 13 during the supply of the raw material to the reforming device 13. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

The present invention relates to a hydrogen generator and a fuel cell system.

  A fuel cell system includes a hydrogen generator that generates steam by reforming raw materials such as city gas and LP gas to produce a hydrogen-rich fuel gas, and an electrochemical reaction between the fuel gas generated by the hydrogen generator and an oxidant gas. A fuel cell that generates electricity by reaction.

The configuration of a conventional hydrogen generator for a fuel cell system will be described below.
FIG. 6 is a diagram illustrating a configuration example of a conventional hydrogen generation apparatus, and is a block diagram of an apparatus conforming to the hydrogen generation apparatus described in Patent Document 1.
The conventional hydrogen generator 50 includes, for example, a reformer 13, a transformer 14, and a selective oxidizer 15.
Further, in addition to the above-described devices 13, 14, and 15, the hydrogen generator 50 is provided with a burner 16 as heat supply means for supplying reaction heat to the reformer 13, as shown in FIG. A raw material supplier 17 (for example, a booster pump) for supplying to the mass device 13, a water supplier 19 (for example, a plunger pump) for supplying water to the reformer 13 for the reforming reaction, and a reformer And a temperature detector 21 capable of detecting 13 temperatures.
In the reformer 13, the raw material and water necessary for reforming the raw material (hereinafter referred to as reformed water) are supplied using the raw material supplier 17 and the water supplier 19, and the reformer reaction is performed using the burner 16. The heat is supplied. For this reason, the temperature of the reforming catalyst (detected by the temperature detector 21) is heated to an appropriate temperature, and in such a reforming catalyst, hydrogen-rich fuel gas is generated by the steam reforming reaction using the raw material and the reforming water. Is done.
The hydrogen-rich fuel gas after the steam reforming reaction described above contains about 10% concentration of carbon monoxide. Since this carbon monoxide becomes a poisonous substance for the fuel cell, if the fuel gas after the steam reforming reaction is directly supplied to the polymer electrolyte fuel cell, the power generation performance of the fuel cell is significantly impaired. Therefore, the above-described transformer 14 and selective oxidizer 15 are provided on the downstream side of the reformer 13, whereby the carbon monoxide concentration in the fuel gas can be appropriately reduced.
In the transformer 14, water vapor and carbon monoxide are shifted to hydrogen and carbon dioxide, and the concentration of carbon monoxide in the fuel gas is reduced.
In the selective oxidizer 15, a carbon monoxide selective oxidation reaction for changing carbon monoxide into carbon dioxide is performed, and the concentration of carbon monoxide in the fuel gas is further reduced.
In this way, a hydrogen-rich fuel gas having a carbon monoxide concentration of 10 ppm or less can be generated. When this hydrogen-rich fuel gas is used as a reaction gas of the fuel cell system, the hydrogen-rich fuel gas is supplied to the anode of a fuel cell (not shown), and power generation is performed in the fuel cell. In addition, the apparatus which can utilize the hydrogen produced | generated by the hydrogen production | generation apparatus 50 is not limited to a fuel cell system. For this reason, depending on the type of hydrogen utilization equipment, the installation of the transformer 14 and the selective oxidizer 15 may be omitted.

By the way, in the above-described hydrogen generator 50, it is important for the reliability and durability of the hydrogen generator 50 that an appropriate amount of reforming water can be supplied in a timely manner. For this reason, as shown in FIG. 6, the hydrogen generator 50 is provided with a water flow rate regulator 20, which is adjusted so that the reforming water can be supplied in an appropriate amount (predetermined flow rate) stably. For example, the controller 30 uses the water flow rate adjuster 20 to adjust (control) the pump rotation speed of the water supply device 19 so that the amount of reforming water becomes an appropriate amount. In addition, the controller 30 uses the water flow regulator 20 to adjust the valve opening degree of a control valve (not shown) installed downstream of the water supplier 19 so that the amount of reformed water becomes an appropriate amount ( Control).
The appropriate amount of the above-mentioned reforming water is a predetermined value of the ratio between the water molecules supplied to the reformer 13 and the raw material (number of carbon atoms) (hereinafter sometimes abbreviated as “S / C”). (For example, “S / C” = 3) refers to the amount of reforming water that can be stably maintained. In other words, the controller 30 uses the water flow regulator 20 to adjust the reforming water calculated from the raw material flow rate measured by the flow rate measuring device 18 and a pre-set “S / C” suitable range. The amount of reforming water supplied by the water supply unit 19 is increased or decreased so that the flow rate becomes high.
JP 2004-6093 A

As described above, in order for the steam reforming reaction to proceed appropriately in the reformer 13, it is indispensable that “S / C” is equal to the target value. For example, when the reformer 13 is short of reforming water (“S / C” in the reformer 13 is lower than its target value) due to air stains or failure of the water supply unit 19, the reformer During the operation of No. 13, excessive pyrolysis of the raw material occurs, and the carbon component in the raw material is deposited. As a result, carbon adheres to the reforming catalyst, causing catalyst deterioration of the reforming catalyst and adversely affecting the durability of the hydrogen generator 50.
Further, when “S / C” decreases, the amount of hydrogen generated in the reformer 13 decreases, which causes various inconveniences in the fuel cell system.
For example, the decrease in “S / C” increases the concentration of carbon monoxide in the fuel gas, thereby reducing the reliability of the hydrogen generator. In addition, due to the decrease in “S / C”, hydrogen necessary for power generation of the fuel cell may not be supplied, and the amount of power generation of the fuel cell may decrease, leading to the power generation stop of the fuel cell. As a result, the reliability of the entire fuel cell system also decreases.
Therefore, as a measure for preventing various inconveniences caused by the decrease in “S / C”, it is assumed that a reforming water flow meter capable of monitoring the reforming water flow rate is installed. As a result, when the measured value of the reforming water flow meter deviates from the target value of the reforming water flow rate, it can be expected that the reforming water supply abnormality notification or the forced supply stop of the raw material can be performed.

  However, when the above-described reforming water flow meter is installed, as a result of investigation, it has been found that substances mixed or dissolved in the reforming water adhere to the reforming water flow meter. It was also found that the product resulting from the rust of the reforming water flow meter due to the dissolved oxygen of the reforming water adheres. Therefore, even if the reforming water flow meter is used, there is a possibility that the measured value of the reforming water flow meter itself deviates from the actual flow rate value of the reforming water, so that the reliability of the reforming water measurement cannot be ensured. In the worst case, the reforming water flow meter may fail. In such a case, the reforming water flow meter cannot properly determine the supply abnormality of the reforming water, and eventually, the catalyst due to the carbon deposition in the above reforming catalyst due to the decrease in “S / C”. Incurs deterioration. In other words, the installation of the reforming water flow meter cannot appropriately cope with various inconvenience prevention due to the difference in the ratio between the water molecules supplied to the reformer and the raw material (number of carbon atoms). The reliability and durability of the generator may be impaired.

  The present invention has been made in view of such circumstances, and can appropriately prevent inconvenience caused by a deviation in the ratio of water molecules and raw materials (number of carbon atoms) supplied to the reformer, and is reliable. And it aims at providing the hydrogen generator excellent in durability.

  Another object of the present invention is to provide a fuel cell system equipped with such a hydrogen generator.

In order to solve the above problems, the present invention provides a reformer that generates a hydrogen-containing gas by a reforming reaction using a raw material and water, a raw material supplier that supplies the raw material to the reformer, and the reforming A flow rate measuring device for measuring the flow rate of the raw material supplied to the vessel, a water supply unit for supplying the water to the reformer, and a controller, wherein the controller is a detection value of the flow rate measuring device. The feedback control of the operation amount of the raw material supply device is performed based on the above, and the supply of the water to the reformer after the supply of water to the reformer is started during the supply of the raw material to the reformer Provided is a hydrogen generation device for notifying the supply abnormality of the water or stopping the supply of the raw material to the reformer based on the amount of operation of the raw material supplier instead of the measured value of the flow rate of water .

As a result, without using a water flow meter, compared to a water flow meter, there is no deterioration factor due to substances dissolved in water, oxygen, etc. By configuring so as to detect, it is possible to appropriately cope with water supply abnormality, so that the reliability and durability of the hydrogen generator can be improved.
In addition, since the water supply abnormality can be appropriately dealt with without using the water detector, the hydrogen generator can be made compact and the cost can be reduced.

Moreover, in the hydrogen generator of the present invention, the controller is configured to start supplying water when the operation amount of the raw material supplier at a predetermined time after the start of supplying water is equal to or less than a first threshold value. When the operation amount of the raw material supplier at a predetermined time point after that is equal to or greater than the second threshold value, the water supply abnormality notification or the supply of the raw material to the reformer may be stopped.
In the hydrogen generator of the present invention, the controller may be configured such that when the amount of change in the operation amount of the raw material supplier in a predetermined period after the start of the supply of water is equal to or greater than a third threshold, When the amount of change in the manipulated variable of the raw material supplier in a predetermined period after the start of the supply is less than or equal to a fourth threshold value, the supply abnormality notification of the water or the supply of the raw material to the reformer is stopped. You may go.

As a result, even when there is a disturbance in the raw material feeder or when the operation amount of the raw material supplier changes over time, the amount of change in the operation amount after the start of the supply of reforming water is used to appropriately adjust the operation amount. A comparison can be made.
Moreover, in the hydrogen generator of the present invention, the controller is configured such that when the change rate of the operation amount of the raw material supplier in a predetermined period after the start of the supply of water is equal to or greater than a fifth threshold, When the rate of change of the operation amount of the raw material supplier in a predetermined period after the start of supply is equal to or less than a sixth threshold, the abnormal supply of water or the supply stop of the raw material to the reformer is stopped. You may go.

  As a result, even when there is a disturbance in the raw material feeder or when the manipulated variable of the raw material feeder changes over time, an appropriate relative amount of manipulated variable can be obtained using the rate of change of the manipulated variable after the start of reforming water supply. A comparison can be made.

  In the hydrogen generator of the present invention, the controller feedback-controls the operation amount of the raw material supplier so that the detected value of the flow rate measuring device becomes a predetermined target value in relation to the flow rate of the water. May be.

  The hydrogen generator of the present invention further includes a temperature detector that detects the temperature of the reformer, and the controller supplies the raw material supplier when the temperature detected by the temperature detector is equal to or lower than a seventh threshold value. The water supply abnormality notification or the supply of the raw material to the reformer may be stopped using the manipulated variable.

  In the hydrogen generator of the present invention, the predetermined time point or the predetermined period is within a period in which the target flow rate of the raw material supplied from the raw material supplier is maintained constant after the start of the water supply. It may be set.

  Thereby, the change of the operation amount by abnormal supply of reforming water can be grasped easily.

  Further, if the seventh threshold value is set to a lower limit temperature at which carbon deposition due to thermal decomposition of the raw material at the reforming catalyst in the reformer occurs, the reforming water is reduced before the reformer reaches the temperature. Therefore, it is possible to appropriately prevent the deterioration of the reforming catalyst of the reformer. Moreover, if it is the temperature raising operation | movement period of a reformer, since the target flow volume of the raw material normally supplied from a raw material supply device is maintained constant, it is convenient.

  The present invention also provides a fuel cell system comprising the hydrogen generator described above and a fuel cell that generates electric power using the hydrogen-containing gas supplied from the hydrogen generator.

  Thereby, a fuel cell system excellent in reliability and durability can be obtained.

  According to the present invention, it is possible to appropriately prevent inconvenience caused by a difference in the ratio between the water molecules supplied to the reformer and the raw material (the number of carbon atoms), and to obtain a hydrogen generator excellent in reliability and durability. It is done.

  Moreover, according to this invention, the fuel cell system provided with such a hydrogen generator is also obtained.

  Hereinafter, preferred embodiments 1, 2 and 3 of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration example of the hydrogen generator according to Embodiment 1 of the present invention.

  The hardware configuration of the hydrogen generator 50A shown in FIG. 1 is the same as the hardware configuration of the conventional hydrogen generator 50 shown in FIG. Accordingly, the components of the hydrogen generator 50A of the present embodiment corresponding to the components of the conventional hydrogen generator 50 are assigned the same reference numerals as those used in FIG. The description will be omitted or abbreviated as appropriate.

  That is, for the hydrogen generator 50A of this embodiment, the reforming water supply abnormality determination using the operation amount of the raw material supplier 17 is performed in the storage unit (an internal memory such as a ROM; not shown) of the controller 30A. Although the corresponding program (described later) is stored, it is distinguished from the conventional hydrogen generator 50 in which the program is not stored in the storage unit. However, the conventional hydrogen generator 50 is used as it is in hardware. it can.

  The controller 30A includes a microprocessor and the like, and includes a single control unit (microprocessor), and also includes a control unit group that controls the hydrogen generator 50A in cooperation with a plurality of control units. May be.

  Next, an operation example of the hydrogen generator 50A of the present embodiment will be described.

  The hydrogen generator 50A is configured to be started by an operation start signal (control signal) from the controller 30A, and is configured to be stopped by an operation stop signal (control signal) from the controller 30A.

  The hydrogen generator 50A may include means (for example, an operation state display unit; not shown) for notifying the user of the current operation state (for example, starting or stopping) of the hydrogen generator 50A. Thereby, based on the above-described control signal from the controller 30A, the current operation state of the hydrogen generator 50A can be displayed on the operation state display unit, and the controller 30A can display the operation state display unit as described later. It is also possible to notify the supply abnormality of reforming water.

  When the hydrogen generator 50A is activated, the raw material supplier 17 supplies the raw material to the reformer 13, and the water supply device 19 supplies the reformed water to the reformer 13. In this case, as shown in FIG. 2A, the controller 30A causes the raw material flow rate (detected value) measured by the flow rate measuring device 18 to be the target flow rate stored in the storage unit of the controller 30A. The operation amount of the raw material supplier 17 is feedback-controlled.

  In the present embodiment, a DC voltage (hereinafter, abbreviated as “voltage”) supplied to the raw material supplier 17 can be used as an operation amount of the raw material supplier 17 (booster booster pump). That is, when the voltage for adjusting the output of the raw material supplier 17 (booster pump) changes in a predetermined adjustment range (for example, a range of 1.0 to 5.0 V), the raw material flow rate (control amount) discharged from the raw material supplier 17 Therefore, the above-described voltage is used as an operation amount for feedback control so that the raw material flow rate discharged from the raw material supplier 17 matches the target flow rate. Thereby, in the hydrogen generator 50A, even if any disturbance occurs that disturbs the flow rate of the raw material discharged from the raw material supplier 17, an appropriate amount of raw material can be stably supplied to the reformer 13.

  Since the voltage adjustment range described above varies depending on the control system of the raw material supplier 17, the voltage adjustment range is appropriately selected based on the control system of the raw material supplier.

  Further, in this embodiment, the voltage supplied to the raw material supplier 17 is the operation amount of feedback control by the controller 30A, but the operation amount is appropriately determined depending on the configuration of the control target (raw material supplier 17). Will be modified. For example, the operation amount of the feedback control by the controller 30A may be a current supplied to the raw material supplier 17 in addition to the voltage described above. When AC power is supplied to the raw material supplier 17, the operation amount of feedback control by the controller 30A may be the frequency or duty ratio of the AC power. Furthermore, when the discharge raw material flow rate of the raw material supplier 17 is adjusted by the control valve, the operation amount of the feedback control by the controller 30A may be the opening degree of the valve.

  Further, the controller 30A controls the water so that the reforming water supply amount is calculated from the raw material flow rate measured by the flow rate measuring device 18 and a suitable range of “S / C” stored in the controller 30A in advance. The operation of the feeder 19 (the output of the water flow regulator 20) is controlled. As a result, an appropriate amount of reforming water is supplied to the reformer 13, and the steam reforming reaction with the reforming catalyst using the raw material and the reforming water proceeds in the reformer 13 as described above. At this time, the controller 30 </ b> A sends a part of the raw material to the burner 16 and combusts the raw material in the burner 16. Thereby, the amount of heat necessary for the reforming reaction of the reforming catalyst can be covered. Further, the controller 30A sends the fuel gas discharged from the reformer 13 in the order of the transformer 14 and the selective oxidizer 15, and appropriately performs the shift reaction of the transformer 14 and the carbon monoxide selective oxidation reaction of the selective oxidizer 15. Although the operations of the transformer 14 and the selective oxidizer 15 are controlled so that the operation can proceed, the detailed description is omitted because these operations are known.

  By the operation control of the hydrogen generator 50A by the controller 30A, the hydrogen generator 50A can generate hydrogen-rich fuel gas for the fuel cell.

  Here, as described above, the reforming reaction in the reformer 13 has a suitable range of “S / C”, and “S / C” needs to be about 2.0 at a minimum. In a state where “S / C” is less than 2.0, when the reforming catalyst of the reformer 13 is heated by the burner 16 and the steam reforming reaction of the reforming catalyst proceeds, the reformer 13 becomes short of water. I fall. As a result, the raw material is decomposed in the reforming catalyst, and carbon is deposited. When the reforming catalyst is covered with carbon, the performance of the reforming catalyst deteriorates and a sufficient amount of fuel gas cannot be generated.

  In the present embodiment, the steam remaining without being used in the steam reforming reaction of the reformer 13 is used for the shift reaction in the transformer 14. In this case, when “S / C” is less than 2.0, the amount of water that can be supplied to the transformer 14 decreases. Then, the transformer 14 cannot sufficiently reduce carbon monoxide in the fuel gas. When such fuel gas is supplied to the fuel cell, the catalyst of the fuel cell is poisoned by carbon monoxide in the fuel gas, and the fuel cell cannot perform appropriate power generation. However, the steam (reformed water) supplied to the reformer 13 is configured to be able to supply to the transformer 14 the portion not used for the reforming reaction. The system is not limited to this. For example, water may be supplied to the transformer 14 separately from the reformer 13 by branching the supply path between the water supplier 19 and the reformer 13. Further, water may be supplied to the transformer 14 using a water supply system that is completely different from the water supply system to the reformer 13.

  On the other hand, even if the supply amount of the reforming water exceeds the target value, there are the following disadvantages. When “S / C” exceeds the upper limit of the preferable range, the amount of heat necessary for evaporating the reformed water into steam in the reformer 13 increases, so the efficiency of the reformer 13 decreases. Further, when excessive steam that is not used in the steam reforming reaction of the reforming catalyst is condensed, the reforming catalyst becomes wet and the performance of the reforming catalyst is deteriorated. Further, by stopping the reformer 13 with a large amount of water remaining, the rapid increase in the temperature of the reformer 13 is inhibited at the next start-up of the hydrogen generator 50A. As a result, the hydrogen generator 50A The startup time of becomes longer.

  For the above reason, in this embodiment, the controller 30A sets the supply amount of the reforming water supplied to the reformer 13 to “S / C = 3.0” (the above-mentioned “S / C” = 2. The operation of the water supply device 7 is controlled so that the margin is 0).

  However, if the hydrogen-rich fuel gas delivered from the hydrogen generator 50A satisfies the specifications required for the hydrogen-using device, the reformer 13 is not necessarily set to the target value of “S / C” described above. There is no need.

  Here, in the water supply device 19, for example, if air or dust is generated, it is considered that an appropriate amount (regular supply amount) of reforming water cannot be supplied to the reformer 13 by the water supply device 19. That is, even if the water supply unit 7 is moved under the same driving conditions as the normal conditions of the water supply unit 19, the supply amount of the reforming water supplied to the reformer 13 may deviate from the target value. As a result, due to insufficient supply of reforming water, carbon deposition on the reforming catalyst may occur due to thermal decomposition of excess raw materials, and the performance of the reforming catalyst may deteriorate. In addition, there are cases where the efficiency of the reformer 13 decreases due to excessive supply of reforming water, and the performance of the reforming catalyst based on the wetness of the reforming catalyst may deteriorate.

  Therefore, the present embodiment is characterized in that the controller 30 </ b> A can appropriately perform determination and response to abnormal supply of reforming water to the reformer 13 based on the operation amount of the raw material supplier 17.

  Hereinafter, the determination of the reforming water supply abnormality and the response when the reforming water supply is abnormal, which are characteristic parts of the present embodiment, will be described in detail.

  The storage unit of the controller 30A stores a reforming water supply abnormality determination / response program, which is read by the CPU of the controller 30A at an appropriate time for operation of the hydrogen generator 50A. The determination and response of the reforming water supply abnormality described in the above are performed while controlling each device of the hydrogen generator 50A.

  FIG. 3 shows the amount of operation of the raw material supplier by the controller when the reforming water supply to the reformer is normal, by the controller when the reforming water supply to the reformer is abnormal (reforming water flow rate: zero). It is the figure shown in comparison with the operation amount of a raw material supply device.

  First, a change in the operation amount of the raw material supplier 17 when the reforming water is normally supplied to the reformer 13 will be described.

  The controller 30A feeds back the operation amount of the raw material supplier 17 so that the raw material at a constant flow rate (here, 1.5 NLM) indicated by white circles (◯) in FIG. I have control. The raw material flow rate is measured (monitored) by the flow rate measuring device 18 shown in FIG. In this case, as indicated by the black diamonds (♦) in FIG. 3, the controller 30A determines the supply amount of reforming water calculated from the raw material flow rate and the preset “S / C” = 3.0. Thus, the supply amount of the reforming water to the reformer 13 is controlled using the water supplier 7.

  Then, when the supply of reforming water is started by the water supplier 7, the reformer 13 generates steam due to the reforming water evaporation, so that the internal pressure of the reformer 13 increases. Such an increase in internal force of the reformer 13 acts in the direction of decreasing the raw material flow rate supplied to the reformer 13, but as described above, the controller 30 </ b> A has the raw material flow rate measured by the flow rate measuring device 18. The feedback control is performed on the operation amount of the raw material supplier 17 so that the target flow rate of raw material (here, 1.5 NLM) stored in the storage unit of the controller 30A is obtained. Therefore, the operation amount of the raw material supplier 17 controlled by the controller 30A is equal to the time after the start of the supply of reforming water to the reformer 13, as indicated by the black squares (■) in FIG. It increases with time (internal pressure rise of the reformer 13). Thereby, the raw material flow rate measured by the flow rate measuring device 18 can be kept constant.

  In this embodiment, the operation amount of the raw material supplier 17 is feedback controlled so as to keep the raw material flow rate at 1.5 NLM. However, the same flow rate as in this embodiment may not be used, and the hydrogen generator Other values may be used as long as the raw material flow rate is suitable for the above characteristics.

  Next, a change in the operation amount of the raw material supplier 17 when no reforming water is supplied to the reformer 13 (an example of abnormal reforming water supply) will be described.

  When the reforming water supplied to the reformer 13 is less than the normal supply amount, the amount of steam generated in the reformer 13 decreases. Then, the internal pressure of the reformer 13 is also lower than when the reforming water is normally supplied. As a result, the amount of operation of the raw material supplier 17 by the controller 30A becomes lower than when the amount of reforming water supplied is normal.

  FIG. 3 illustrates, as an extreme example, a profile of the operation amount of the raw material supplier 17 when no reforming water is supplied to the reformer 13 (when the reforming water flow rate is zero). In this case, as shown by the black triangle (▲) in FIG. 3, the operation amount of the raw material supplier 17 remains substantially constant.

  As described above, the controller 30A can determine the supply abnormality of the reforming water based on the difference in the operation amount of the raw material supplier 17 between the case where the supply of the reforming water is normal and the case where it is abnormally low. As described above, this reforming water supply abnormality determination technique has been devised for the first time by paying attention to the correlation between the change in the supply amount of the reforming water and the change in the operation amount of the raw material supplier 17. . That is, in this abnormality determination technique, as shown in FIG. 2 (b), the flow rate is as follows: "Acquisition of raw material flow rate" → "Control calculation" → "Output of manipulated variable" → "Obtainment of raw material flow rate" When feedback control of the operation amount of the raw material supplier 17 is performed based on the detection value (raw material flow rate) of the measuring device 18, this operation amount is acquired by the controller 30A, and at the operation amount detection timing (details will be described later). Based on the above operation amount, the supply abnormality determination of the reforming water is made.

  In this case, in this embodiment, as shown in FIG. 3, a threshold value (first threshold value; described later) of the operation amount of the raw material supplier 17 is set. Then, at the operation amount detection timing, when the operation amount is equal to or less than the first threshold (for example, in the case of the operation amount A in FIG. 3), the controller 30 </ b> A supplies reforming water (in this case, reforming). It is determined that the water supply is insufficient.

  Conversely, the controller 30A determines that there is no abnormal supply of reforming water when the manipulated variable exceeds the first threshold (for example, manipulated variable B in FIG. 3) at the manipulated variable detection timing.

  Further, in this embodiment, when the controller 30A determines that there is an abnormality in the supply of reforming water, the controller 30A operates the hydrogen generator 50A so that the reforming water supply abnormality processing operation is performed. To control.

  For example, the controller 30A may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved. The controller 30 </ b> A may forcibly stop the raw material supply to the reformer 13 using the raw material supplier 17. Thereby, when the reforming water is insufficiently supplied, carbon deposition due to excessive raw material pyrolysis at the reforming catalyst can be appropriately prevented.

  Further, here, as shown in FIG. 3, as the above-mentioned first threshold value, a steady value (operation amount) of an operation amount assumed when a 1.5 NLM raw material is sent to the reformer 13 when the reforming water supply is normal. A numerical value lower by about 10% than B) is used. However, the operation amount (first threshold value) serving as a reference for such abnormality determination varies depending on the configuration of the hydrogen generator, the controllability of the controller 30A, the design margin, and the like, and therefore is not necessarily different from that of the present embodiment. The same numerical value may not be used, and other values that meet such a matter may be used.

  Next, a change in the operation amount of the raw material supplier 17 when the reforming water is excessively supplied to the reformer 13 of the hydrogen generator 50A (another example of the reforming water supply abnormality) will be described.

  When the reforming water supplied to the reformer 13 is larger than the normal supply amount, the amount of water vapor generated in the reformer 13 is more than necessary. Then, the internal pressure of the reformer 13 also becomes higher than when the supply of reforming water is normal. As a result, the amount of operation of the raw material supplier 17 by the controller 30A becomes higher than when the supply of reforming water is normal. In addition, illustration of the operation amount profile of the raw material supply device 17 in this case is omitted.

As described above, the controller 30A can determine the supply abnormality of the reforming water based on the difference in the operation amount of the raw material supplier 17 between when the reforming water supply is normal and when it is abnormally large.
In this abnormality determination technique, as shown in FIG. 2 (b), a flow rate measuring instrument such as “Acquisition of raw material flow rate” → “Control calculation” → “Output of operation amount” → “Acquisition of raw material flow rate” →. When feedback control of the operation amount of the material supply unit 17 is performed based on the detected value (material flow rate) of 18, the operation amount is acquired by the controller 30A, and the operation amount is detected at the operation amount detection timing (details will be described later). An abnormal supply of reforming water is determined based on the operation amount.

  In this case, in the present embodiment, as shown in FIG. 3, a threshold value (second threshold value; described later) of the operation amount of the raw material supplier 17 is set. Then, at the operation amount detection timing, the controller 30A determines that the supply of reforming water is abnormal (in this case, excessive supply of reforming water) when the operation amount is equal to or greater than the second threshold value.

  Conversely, the controller 30A determines that there is no abnormal supply of reforming water when the manipulated variable is less than the second threshold at the manipulated variable detection timing.

  Further, in this embodiment, when the controller 30A determines that there is an abnormality in the supply of reforming water, the controller 30A operates the hydrogen generator 50A so that the reforming water supply abnormality processing operation is performed. To control.

  For example, the controller 30A may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved.

  Further, as shown in FIG. 3, as the above-mentioned second threshold value, from a steady value (operation amount B) of an operation amount that is assumed when 1.5 NLM raw material is sent to the reformer 13 when the reforming water supply is normal. Also, a numerical value about 10% higher is used. However, the operation amount (second threshold value) serving as a reference for such abnormality determination varies depending on the configuration of the hydrogen generator 50A, the controllability of the controller 30A, the design margin, and the like. It is not necessary to use the same numerical value as, and other values that fit such matters may be used.

  Next, the operation amount detection timing at which reformed water supply abnormality determination is made will be described.

  As shown in FIG. 3, the operation amount detection timing of the present embodiment is set at a predetermined time after the supply of reforming water to the reformer 13 is started during the supply of the raw material to the reformer 13. Has been. When the reforming water is normally supplied to the reformer 13, the operation amount of the raw material supplier 17 increases at a predetermined speed based on the increase in the internal pressure of the reformer 13, and then the raw material supplier 17 Since the change in the operation amount becomes stable, the operation amount detection timing described above is preferably set after stabilization of the operation amount change of the raw material supplier 17 when the reforming water supply is normal. Accordingly, it is possible to clearly distinguish between the case where the reforming water is normally supplied to the reformer 13 and the case where the reforming water is not supplied, which is advantageous in that it is possible to eliminate a determination error (false detection).

  Further, the predetermined time point is set within a period in which the target flow rate of the raw material supplied from the raw material supplier 17 is maintained constant (here, 1.5 NLM) after the start of the supply of reforming water. It is preferable. Thereby, the change of the operation amount (absolute value) by the abnormal supply of reforming water can be easily grasped.

  In the present embodiment, as shown in FIG. 3, the operation amount detection timing when the supply of reforming water is abnormally low and the operation amount detection timing when the supply of reforming water is abnormally high are the same time. However, it is not always necessary that both are set at the same time, and both may be set as appropriate within an arbitrary section suitable for the characteristics of the hydrogen generator.

  As described above, the hydrogen generator 50A of this embodiment uses the flow rate measuring device 18 for measuring the raw material flow rate instead of using the reforming water flow meter, and the raw material supplier 17 that supplies the raw material to the reformer 13. On the basis of the manipulated variable, an appropriate determination and response can be made to abnormal supply of reforming water to the reformer 13.

  As a result, it is possible to determine and respond to the supply of reforming water without using a special detector for reforming water, so that the reliability and durability of the hydrogen generator 50A can be improved. In other words, the raw material is usually in a gaseous form, and the flow rate and flow velocity of the raw material are large. Therefore, the possibility of any foreign matter adhering to the flow rate measuring device 18 described above can be attributed to the reforming water flow meter. Compared to this, the flow rate measuring device 18 has high reliability and durability.

  In addition, since it is possible to determine and respond to the supply of reforming water without using a special detector for reforming water, the hydrogen generator 50A can be made compact and low in cost.

Furthermore, since the hydrogen-rich fuel gas generated by the hydrogen generator 50A of the present embodiment can be used as a fuel gas for power generation of a fuel cell, the hydrogen generator 50A (selective oxidizer 15) described above is used. By connecting the fuel gas outlet to the anode of the fuel cell via an appropriate pipe (not shown), a fuel cell system having excellent reliability and durability can be constructed.
(Embodiment 2)
Since the hydrogen generator 50B according to the second embodiment of the present invention is the same as the hydrogen generator 50A shown in FIG. 1 in terms of hardware configuration, illustration and description of the configuration of the hydrogen generator 50B according to the present embodiment are omitted. To do.

  For the hydrogen generator 50B of the present embodiment, a program different from the reforming water supply abnormality determination / response program stored in the storage unit of the controller 30A of the first embodiment is stored in the storage unit of the controller 30B. In this respect, it is distinguished from the hydrogen generator 50A of the first embodiment (FIG. 1), but the hydrogen generator 50A can be used as it is in terms of hardware.

  FIG. 4 shows the amount of change in the operation amount of the raw material supplier by the controller when the reforming water supply to the reformer is normal, when the reforming water supply to the reformer is abnormal (reforming water flow rate: zero). It is the figure shown in comparison with the variation | change_quantity of the operation amount of the raw material supply device by a controller.

  Note that the raw material flow rate (circles in FIG. 4), the reforming water flow rate (♦ marks in FIG. 4), the operation amount of the raw material supply unit 17 when the reforming water is normally supplied to the reformer 13 (FIG. 4). ) And the profile of the operation amount of the raw material supplier 17 when no reforming water is supplied to the reformer 13 (marked with ▲ in FIG. 4) in the first embodiment (FIG. 3). Therefore, the detailed description thereof is omitted.

  In the first embodiment, the controller 30A determines the supply abnormality of the reforming water supplied to the reformer 13 based on the operation amount of the raw material supplier 17, but in the present embodiment, the controller 30A is shown in FIG. As described above, the controller 30 </ b> B determines the supply abnormality of the reforming water supplied to the reformer 13 based on the amount of change in the operation amount of the raw material supplier 17.

  Hereinafter, the determination of the reforming water supply abnormality and the response when the reforming water supply is abnormal, which are characteristic parts of the present embodiment, will be described in detail.

  FIG. 4 shows the profile of the operation amount (here, voltage) of the raw material supplier 17 when the supply of reforming water is normal and when it is abnormally low (here, the reforming water flow rate: zero). .

  In the present embodiment, as shown in FIG. 4, the controller 30B acquires the operation amount C at the start of supply of reforming water (first operation amount detection timing), and stores this operation amount C in the storage unit. Remember. Further, the controller 30B acquires the operation amount D (when the reforming water supply is normal) or the operation amount E (when the reforming water supply is abnormal) at the second operation amount detection timing, and these operation amounts are also obtained. Store in the storage unit.

  As with the operation amount detection timing of the first embodiment, the first and second operation amount detection timings are such that the supply of reforming water to the reformer 13 is started during the supply of the raw material to the reformer 13. It is set at a predetermined time after that.

  Further, when the reforming water is normally supplied to the reformer 13, the operation amount of the raw material supplier 17 is increased at a predetermined speed based on the increase in the internal pressure of the reformer 13, and then the raw material supplier Therefore, the second operation amount detection timing is preferably set after the stabilization of the operation amount change of the raw material supplier 17 when the reforming water supply is normal. Accordingly, it is possible to clearly distinguish between the case where the reforming water is normally supplied to the reformer 13 and the case where the reforming water is not supplied, which is advantageous in that it is possible to eliminate a determination error (false detection).

  In addition, as shown in FIG. 4, the first and second manipulated variable detection timings described above have a constant target flow rate of the raw material supplied from the raw material supplier 17 after the start of the supply of reforming water (here, 1.. 5NLM) is preferably set within the period maintained. Thereby, the change of the operation amount (change amount) by the abnormal supply of reforming water can be easily grasped.

  Here, the controller 30B operates the operation amount of the raw material supplier 17 in a predetermined period after the start of supply of the reforming water (here, the period between the first operation amount detection timing and the second operation amount detection timing). The amount of change is calculated. When the supply of the reforming water is normal, the above-described change amount is a voltage difference between the operation amount D and the operation amount C. Further, when the supply of reforming water is abnormally small (here, the reforming water flow rate is zero), the above-described change amount is a voltage difference between the operation amount E and the operation amount C.

  As described above, based on the difference in the amount of change in the operation amount of the raw material supplier 17 between the case where the supply of reforming water is normal and the case where it is abnormally low, the controller 30B Can be judged.

  In particular, in the present embodiment, even if a disturbance to the raw material supplier 17 or a change with time in the capacity of the raw material supplier 17 occurs (for example, variation in the operation amount C of the raw material supplier 17), the operation amount of the raw material supplier 17 If the amount of change is taken as a reference, such disturbances and changes can be canceled out, so it is possible to appropriately determine the supply abnormality of reforming water. That is, even when there is a disturbance in the raw material supply unit 17 or when the operation amount of the raw material supply unit 17 changes with time, an appropriate relative amount of operation amount can be obtained using the change amount of the operation amount after the start of the reforming water supply. Comparison can be made, whereby the supply abnormality of the reforming water can be determined more accurately.

  In this embodiment, considering the case where the supply of reforming water supplied to the reformer 13 is abnormally small, as shown in FIG. A threshold value (described later) is set. Then, the controller 30B has an abnormal supply of reforming water (here, insufficient supply of reforming water) when the change amount of the manipulated variable is equal to or smaller than the third threshold value in the predetermined period. judge.

  Conversely, the controller 30B determines that there is no abnormal supply of reforming water when the change amount of the manipulated variable exceeds the third threshold value during the predetermined period.

  As in the first embodiment, in this embodiment, when the controller 30B determines that there is an abnormality in the supply of reforming water, the controller 30B performs the hydrogen supply abnormality processing operation so that the reforming water supply abnormality processing operation is performed. The operation of the generation device 50B is controlled.

  For example, the controller 30B may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved. The controller 30 </ b> B may forcibly stop the raw material supply to the reformer 13 using the raw material supplier 17. Thereby, when the reforming water is insufficiently supplied, carbon deposition due to excessive raw material pyrolysis at the reforming catalyst can be appropriately prevented.

  Further, as shown in FIG. 4, the above-mentioned third threshold value is set to a steady value (operation amount D) of an operation amount that is assumed when 1.5 NLM raw material is sent to the reformer 13 when the reforming water supply is normal. On the other hand, a voltage difference (change amount) between the operation amount and the operation amount C that is reduced by 10% is used. Note that the change amount (third threshold value) of the manipulated variable that serves as a criterion for such abnormality determination varies depending on the configuration of the hydrogen generator, the controllability of the controller, the design margin, and the like. An appropriate value that fits the matter may be selected.

  In the present embodiment, in consideration of a case where the supply of reforming water supplied to the reformer 13 is abnormally large, as shown in FIG. A fourth threshold value (described later) is set. Then, the controller 30B has an abnormal supply of reforming water (here, excessive supply of reforming water) when the change amount of the manipulated variable is equal to or greater than the fourth threshold value in the predetermined period. judge.

  Conversely, the controller 30B determines that the supply of reforming water is not abnormal when the change amount of the manipulated variable is less than the fourth threshold value in the predetermined period.

  As in the first embodiment, in this embodiment, when the controller 30B determines that there is an abnormality in the supply of reforming water, the controller 30B performs the hydrogen supply abnormality processing operation so that the reforming water supply abnormality processing operation is performed. The operation of the generation device 50B is controlled. For example, the controller 30B may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved.

  Further, as shown in FIG. 4, the above-mentioned fourth threshold value is set to a steady value (operation amount D) of an operation amount assumed when a 1.5 NLM raw material is sent to the reformer 13 when the reforming water supply is normal. On the other hand, a voltage difference (change amount) between the operation amount and the operation amount C that is increased by about 10% is used. Note that the amount of change in the operation amount (fourth threshold value) that serves as a reference for such abnormality determination varies depending on the configuration of the hydrogen generator, the controllability of the controller, the design margin, and the like. An appropriate value that fits the matter may be selected.

  In the present embodiment, as shown in FIG. 4, first and second operation amount detection timings when the supply of reforming water is abnormally low, and first and second when the supply of reforming water is abnormally high Although the manipulated variable detection timing is set at the same time, it is not always necessary that both are set at the same time, and both may be set as appropriate within an arbitrary section suitable for the characteristics of the hydrogen generator.

  As described above, the hydrogen generator 50B of the present embodiment uses the flow rate measuring device 18 for measuring the raw material flow rate instead of using the reforming water flow meter, and the raw material supplier 17 that supplies the raw material to the reformer 13. Based on the amount of change in the manipulated variable, it is configured so that appropriate determination and response can be made to abnormal supply of reforming water to the reformer 13.

  As a result, since it is possible to determine and respond to abnormal supply of reforming water without using a special detector for reforming water, it is possible to improve the reliability and durability of the hydrogen generator 50B. In other words, the raw material is usually in a gaseous form, and the flow rate and flow velocity of the raw material are large. Therefore, the possibility of any foreign matter adhering to the flow rate measuring device 18 described above can be attributed to the reforming water flow meter. Compared to this, the flow rate measuring device 18 has high reliability and durability.

  In addition, since it is possible to determine and deal with the supply abnormality of the reforming water without using a special detector for the reforming water, the hydrogen generator 50B can be made compact and low in cost.

  Furthermore, since the hydrogen-rich fuel gas generated by the hydrogen generator 50B of the present embodiment can be used as a fuel gas for power generation of the fuel cell, the hydrogen generator 50B (selective oxidizer 15) described above is used. By connecting the fuel gas outlet to the anode of the fuel cell via an appropriate pipe (not shown), a fuel cell system having excellent reliability and durability can be constructed.

In particular, in this embodiment, even when there is a disturbance in the raw material supplier 17 or when the operation amount of the raw material supplier 17 changes with time, the operation is performed using the amount of change in the operation amount after the start of the reforming water supply. Appropriate relative comparison of the amounts can be performed, whereby the supply abnormality of reforming water can be determined more accurately.
(Embodiment 3)
The hydrogen generation apparatus 50C according to Embodiment 3 of the present invention is the same as the hydrogen generation apparatus 50A shown in FIG. 1 in terms of hardware configuration, and therefore illustration and description of the configuration of the hydrogen generation apparatus 50C according to this embodiment are omitted. To do.

  For the hydrogen generator 50C of the present embodiment, a program different from the reforming water supply abnormality determination / corresponding program stored in the storage unit of the controller 30A of the first embodiment is stored in the storage unit of the controller 30C. In this respect, it is distinguished from the hydrogen generator 50A of the first embodiment (FIG. 1), but the hydrogen generator 50A can be used as it is in terms of hardware.

  FIG. 5 shows the rate of change in the amount of operation of the raw material supplier by the controller when the reforming water supply to the reformer is normal, and the raw material supply by the controller when the reforming water supply is abnormal (reforming water flow rate: zero) It is the figure shown in comparison with the change rate of the operation amount of a vessel.

  Note that the raw material flow rate (circles in FIG. 5), the reforming water flow rate (♦ marks in FIG. 5), and the operation amount of the raw material supply unit 17 when the reforming water is normally supplied to the reformer 13 (FIG. 5). ) And the profile of the manipulated variable of the raw material supplier 17 when no reforming water is supplied to the reformer 13 (marked with ▲ in FIG. 5) in the first embodiment (FIG. 3). Therefore, the detailed description thereof is omitted.

  In the first embodiment, the controller 30A determines the supply abnormality of the reforming water supplied to the reformer 13 based on the operation amount of the raw material supplier 17, but in the present embodiment, it is shown in FIG. As described above, the controller 30C determines the supply abnormality of the reforming water supplied to the reformer 13 based on the change rate of the operation amount of the raw material supplier 17 (change amount of the operation amount per unit time). Yes.

  Hereinafter, the determination of the reforming water supply abnormality and the response when the reforming water supply is abnormal, which are characteristic parts of the present embodiment, will be described in detail.

  FIG. 5 shows a profile of the operation amount (here, voltage) of the raw material supplier 17 when the supply of reforming water is normal and when it is abnormally low (here, the reforming water flow rate: zero). .

  In the present embodiment, as shown in FIG. 5, the controller 30C acquires the operation amount C at the start of the supply of reforming water (first operation amount detection timing), and stores this operation amount C in the storage unit. Remember. Further, the controller 30C acquires the operation amount D (when the reforming water supply is normal) or the operation amount E (when the reforming water supply is abnormal) at the second operation amount detection timing, and these operation amounts are also obtained. Store in the storage unit.

  As with the operation amount detection timing of the first embodiment, the first and second operation amount detection timings are such that the supply of reforming water to the reformer 13 is started during the supply of the raw material to the reformer 13. It is set at a predetermined time after that.

  Further, when the reforming water is normally supplied to the reformer 13, the operation amount of the raw material supplier 17 is increased at a predetermined speed based on the increase in the internal pressure of the reformer 13, and then the raw material supplier Therefore, the second operation amount detection timing is preferably set after the stabilization of the operation amount change of the raw material supplier 17 when the reforming water supply is normal. Accordingly, it is possible to clearly distinguish between the case where the reforming water is normally supplied to the reformer 13 and the case where the reforming water is not supplied, which is advantageous in that it is possible to eliminate a determination error (false detection).

  Further, as shown in FIG. 5, the first and second manipulated variable detection timings described above have a constant target flow rate of the raw material supplied from the raw material supplier 17 after the start of the supply of reforming water (here, 1.. 5NLM) is preferably set within the period maintained. Thereby, the change of the operation amount (change rate) by abnormal supply of reforming water can be grasped easily.

  Here, the controller 30C operates the operation amount of the raw material supplier 17 in a predetermined period after the start of the supply of reforming water (here, the period between the first operation amount detection timing and the second operation amount detection timing). Calculate the rate of change. When the supply of reforming water is normal, the rate of change described above indicates the voltage difference between the manipulated variable D and the manipulated variable C, and the time between the second manipulated variable detection timing and the first manipulated variable detection timing. The value divided by the difference of. Further, when the supply of reforming water is abnormally small (when the reforming water flow rate is zero), the above change rate is obtained by detecting the difference in voltage between the manipulated variable E and the manipulated variable C using the second manipulated variable detection. This is a value divided by the time difference between the timing and the first operation amount detection timing.

  As described above, based on the difference in the change rate of the operation amount of the raw material supplier 17 between the case where the supply of reforming water is normal and the case where the reforming water is abnormally small, the controller 30C Can be judged.

  In particular, in the present embodiment, even if a disturbance to the raw material supplier 17 or a change with time in the capacity of the raw material supplier 17 occurs (for example, variation in the operation amount C of the raw material supplier 17), the operation amount of the raw material supplier 17 If the rate of change is taken as a reference, such disturbances and changes can be canceled out, so it is possible to appropriately determine the supply abnormality of reforming water. That is, even when there is a disturbance in the raw material supplier 17 or when the operation amount of the raw material supplier 17 changes with time, an appropriate relative amount of the operation amount can be determined using the change rate of the operation amount after the start of the reforming water supply. Comparison can be made, whereby the supply abnormality of the reforming water can be determined more accurately.

  In the present embodiment, considering the case where the supply of reforming water supplied to the reformer 13 is abnormally small, as shown in FIG. A threshold value (described later) is set. Then, the controller 30C has an abnormal supply of reforming water (here, insufficient supply of reforming water) when the change rate of the manipulated variable is equal to or less than the fifth threshold value in the predetermined period. judge.

  Conversely, the controller 30C determines that the supply of reforming water is not abnormal when the change rate of the manipulated variable exceeds the fifth threshold value during the predetermined period.

  As in the first embodiment, in this embodiment, when the controller 30C determines that there is an abnormality in the supply of reforming water, the controller 30C performs the hydrogen supply abnormality processing operation so that the reforming water supply abnormality processing operation is performed. The operation of the generation device 50C is controlled.

  For example, the controller 30C may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved. The controller 30 </ b> C may forcibly stop the raw material supply to the reformer 13 using the raw material supplier 17. Thereby, when the reforming water is insufficiently supplied, carbon deposition due to excessive raw material pyrolysis at the reforming catalyst can be appropriately prevented.

  Further, as shown in FIG. 5, the above-mentioned fifth threshold value is set to a steady value (operation amount D) of an operation amount assumed when a 1.5 NLM raw material is sent to the reformer 13 when the reforming water supply is normal. On the other hand, the voltage difference (ΔV1) between the operation amount and the operation amount C, which is reduced by 10%, is divided by the time difference (Δt) between the second operation amount detection timing and the first operation amount detection timing. The obtained value (ΔV1 / Δt) is used. Note that the change rate (fifth threshold value) of the manipulated variable serving as a reference for such abnormality determination varies depending on the configuration of the hydrogen generator, the controllability of the controller, the design margin, and the like. An appropriate value that fits the matter may be selected.

  In the present embodiment, in consideration of the case where the amount of reforming water supplied to the reformer 13 is abnormally large, as shown in FIG. A sixth threshold (to be described later) is set. Then, the controller 30C has an abnormal supply of reforming water (in this case, excessive supply of reforming water) when the change rate of the manipulated variable is equal to or greater than the sixth threshold in the predetermined period. judge.

  Conversely, the controller 30C determines that there is no abnormal supply of reforming water when the change rate of the manipulated variable is less than the sixth threshold value during the predetermined period.

  As in the first embodiment, in this embodiment, when the controller 30C determines that there is an abnormality in the supply of reforming water, the controller 30C performs the hydrogen supply abnormality processing operation so that the reforming water supply abnormality processing operation is performed. The operation of the generation device 50C is controlled.

  For example, the controller 30C may notify the user that the supply of reforming water is abnormal using an appropriate notification device (for example, an operation state display device or an alarm). As a result, the user can quickly detect the supply abnormality of the reforming water, so that a quick return to the supply abnormality of the reforming water can be achieved.

  Further, as shown in FIG. 5, the above-described sixth threshold value is set to the steady value (operation amount D) of the operation amount that is assumed when 1.5 NLM of the raw material is sent to the reformer 13 when the reforming water supply is normal. On the other hand, the voltage difference (ΔV2) between the operation amount and the operation amount C, which is increased by about 10%, is the time difference (Δt) between the second operation amount detection timing and the first operation amount detection timing. The divided value (ΔV2 / Δt) is used. Note that the change rate (sixth threshold value) of the manipulated variable serving as a criterion for such abnormality determination varies depending on the configuration of the hydrogen generator, the controllability of the controller, the design margin, and the like. An appropriate value that fits the matter may be selected.

  In the present embodiment, as shown in FIG. 5, the first and second operation amount detection timings when the supply of reforming water is abnormally low, and the first and second operation amount detection timings when the supply of reforming water is abnormally high, The second manipulated variable detection timing is set at the same time, but it is not always necessary that both are set at the same time, and both may be set as appropriate within an arbitrary section suitable for the characteristics of the hydrogen generator.

  As described above, the hydrogen generator 50C of this embodiment uses the flow rate measuring device 18 for measuring the raw material flow rate instead of using the reforming water flow meter, and the raw material supplier 17 that supplies the raw material to the reformer 13. Based on the change rate of the manipulated variable, it is configured so that appropriate determination and response can be made to abnormal supply of reforming water to the reformer 13.

  As a result, it is possible to determine and respond to the abnormal supply of reforming water without using a special detector for reforming water, so that the reliability and durability of the hydrogen generator 50C can be improved. In other words, the raw material is usually in a gaseous form, and the flow rate and flow velocity of the raw material are large. Therefore, the possibility of any foreign matter adhering to the flow rate measuring device 18 described above can be attributed to the reforming water flow meter. Compared to this, the flow rate measuring device 18 has high reliability and durability.

  In addition, since it is possible to determine and respond to the abnormal supply of reforming water without using a special detector for reforming water, it is possible to reduce the size and cost of the hydrogen generator 50C.

  Furthermore, since the hydrogen-rich fuel gas generated by the hydrogen generator 50C of the present embodiment can be used as a fuel gas for power generation of the fuel cell, the hydrogen generator 50C (selective oxidizer 15) described above is used. By connecting the fuel gas outlet to the anode of the fuel cell via an appropriate pipe (not shown), a fuel cell system having excellent reliability and durability can be constructed.

In particular, in this embodiment, even when there is a disturbance in the raw material supplier 17 or when the operation amount of the raw material supplier 17 changes with time, the operation is performed using the change rate of the operation amount after the start of the supply of reforming water. Appropriate relative comparison of the amounts can be performed, whereby the supply abnormality of reforming water can be determined more accurately.
(Modification)
As described above, the operation amount detection timing of the first embodiment, the second operation amount detection timing of the second embodiment, and the second operation amount detection timing of the third embodiment supply the raw material to the reformer 13. In the inside, it is set after the stabilization of the change in the operation amount of the raw material supplier 17 when the reforming water supply is normal. Further, these operation amount detection timings are set within a period in which the target flow rate of the raw material supplied from the raw material supplier 17 is kept constant after the start of the reforming water supply.

  In the hydrogen generator of this modification, the end time of these manipulated variable detection timings is such that the detected temperature of the temperature detector 21 (see FIG. 1) for detecting the temperature of the reformer 13 is a predetermined temperature (seventh threshold; (It will be described later). That is, in this modified example, the controller uses the operation amount of the raw material supplier 17 when the temperature detected by the temperature detector 21 is equal to or lower than the seventh threshold value, and determines reforming water supply abnormality and reforming. The water supply abnormality notification is being executed.

  And the above-mentioned 7th threshold value shall point out the minimum temperature in which the inside of the reformer 13 becomes high temperature, and carbon deposition by the thermal decomposition of a raw material in the reforming catalyst in the reformer 13 occurs.

  As a result, it is possible to determine and cope with the supply abnormality of the reforming water before the carbon deposition on the reforming catalyst in the reformer 13, so that the progress of the deterioration of the reforming catalyst of the reformer 13 can be appropriately performed. Can be prevented.

  In addition, since the target flow rate of the raw material supplied from the raw material supplier 17 is normally kept constant during the temperature raising operation period of the reformer 13, It is convenient because it is easy to obtain consistency.

  The hydrogen generator of the present invention can appropriately prevent inconvenience due to the difference in the ratio between the water molecules supplied to the reformer and the raw material (number of carbon atoms). Therefore, the present invention can be used as a hydrogen generator for a fuel cell system.

It is the block diagram which showed the structural example of the hydrogen generator of Embodiment 1 of this invention. 2 is a conceptual diagram of control of the hydrogen generator of Embodiment 1. FIG. The amount of operation of the raw material feeder by the controller when the reforming water supply to the reformer is normal is the same as that of the raw material feeder by the controller when the reforming water supply to the reformer is abnormal (reforming water flow rate: zero). It is the figure shown in comparison with the operation amount. The amount of change in the amount of operation of the raw material feeder by the controller when the reforming water supply to the reformer is normal is the raw material by the controller when the reforming water supply to the reformer is abnormal (reforming water flow rate: zero) It is the figure shown in comparison with the variation | change_quantity of the operation amount of a feeder. The rate of change in the amount of operation of the raw material supply unit by the controller when the reforming water supply to the reformer is normal is the change rate of the raw material supply unit by the controller when the reforming water supply is abnormal (reforming water flow rate: zero) It is the figure shown in the comparison with the change rate. It is the figure which showed the structural example of the conventional hydrogen generator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 13 Reformer 14 Transformer 15 Selective oxidizer 16 Burner 17 Raw material supply device 18 Flow rate measurement device 19 Water supply device 20 Water flow rate adjustment device 21 Temperature detector 30A, 30B, 30C Controller 50A, 50B, 50C Hydrogen generator

Claims (8)

A reformer that generates a hydrogen-containing gas by a reforming reaction using raw materials and water;
A raw material supplier for supplying the raw material to the reformer;
A flow rate measuring device for measuring the flow rate of the raw material supplied to the reformer;
A water supply for supplying the water to the reformer;
A controller, and
The controller performs feedback control of an operation amount of the raw material supply device based on a detection value of the flow rate measuring device, and supplies the water to the reformer during supply of the raw material to the reformer. Is not based on the measured value of the flow rate of water supplied to the reformer after the start of the operation, but based on the manipulated variable of the raw material supplier, the water supply abnormality notification, or the raw material to the reformer Hydrogen generator that stops supply of water.   The controller is configured such that the amount of operation of the raw material supplier at a predetermined time after the start of water supply is equal to or less than a first threshold value, or the raw material supplier at a predetermined time after the start of water supply. The hydrogen generation apparatus according to claim 1, wherein when the manipulated variable is equal to or greater than a second threshold, the water supply abnormality notification or the supply of the raw material to the reformer is stopped. The controller, when the change amount of the operation amount of the raw material supplier in a predetermined period after the start of the supply of water is greater than or equal to a third threshold, or in the predetermined period after the start of the supply of water The hydrogen generator according to claim 1, wherein when the amount of change in the operation amount of the raw material supplier is equal to or less than a fourth threshold value, the abnormal supply of water is notified or the supply of the raw material to the reformer is stopped. . The controller, when the change rate of the operation amount of the raw material supplier in a predetermined period after the start of the supply of water is equal to or greater than a fifth threshold, or the predetermined period after the start of the supply of water The hydrogen generator according to claim 1, wherein when the rate of change of the operation amount of the raw material supplier is equal to or less than a sixth threshold value, the abnormal supply of water is notified or the supply of the raw material to the reformer is stopped. .   The controller performs feedback control of an operation amount of the raw material supplier so that a detection value of the flow rate measuring device becomes a predetermined target value in relation to the flow rate of water. The hydrogen generator according to any one of the above. A temperature detector for detecting the temperature of the reformer,
The controller uses the operation amount of the raw material supply device when the temperature detected by the temperature detector is equal to or lower than a seventh threshold value, and notifies the water supply abnormality or the raw material to the reformer. The hydrogen generator according to claim 1, wherein the supply is stopped.   The predetermined time point or the predetermined period is set within a period in which a target flow rate of the raw material supplied from the raw material supplier is maintained constant after the water supply is started. The hydrogen generator according to any one of the above. A hydrogen generator according to any one of claims 1 to 7,
A fuel cell that generates electricity using the hydrogen-containing gas supplied from the hydrogen generator;
A fuel cell system comprising:

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