JP2018190568A - Fuel cell device and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell device which suppresses gas leakage detection by a gas meter, and a control method.SOLUTION: A fuel cell device comprises a hot module and a control part. The hot module has a power generation state where power generation is performed by modifying and reacting a gas that is supplied via a gas meter, and a stop state where power generation using the gas is not performed, is shifted from the stop state through a start processing state to the power generation state, and is shifted from the power generation state through stop processing state to the stop state. The control part causes the hot module to maintain the stop state for a predetermined periodical stop term for each predetermined cycle. In a case where the hot module is in the stop state out of the periodical stop term, before a first predetermined time, the control part shifts the hot module to the start processing state and after the first predetermined time, the control part does not shift the hot module to the start processing state. The first predetermined time is a time traced back from a predetermined starting time of a next periodical stop term for a total time of a required time of the start processing state and a required time of the stop processing state.SELECTED DRAWING: Figure 3

Description

  The present disclosure relates to a fuel cell device and a control method.

  2. Description of the Related Art There is known a fuel cell device that performs a reforming reaction of a fuel gas such as city gas and generates power using the obtained hydrogen. Such a fuel cell device is installed in each customer facility, for example. In this case, the fuel cell device generates power using city gas and supplies the power to the load equipment of the customer facility.

  In the customer facility, the fuel cell device is supplied with gas via a gas meter. The gas meter has a security function that automatically shuts off the gas supply when an abnormality in the gas supply is detected. For example, when the gas continues to flow for a predetermined gas leak detection period (for example, 30 days), the gas meter determines that a gas leak has occurred and cuts off the gas supply.

  In order for the fuel cell device to contribute to stable power generation, a continuous supply of gas is required. However, if the gas meter shuts off the gas supply for security, the continuous supply of gas to the fuel cell device is hindered. As a technique for ensuring the continuous supply of gas to the fuel cell device under such restrictions, for example, in Patent Document 1, a predetermined gas cutoff period is provided to suppress detection of gas leaks in the gas meter and avoid gas cutoff. A thermal device is disclosed.

JP 2013-213609 A

  There is room for further improvement in suppressing the occurrence of gas leak detection with a gas meter.

  The present disclosure relates to a fuel cell device and a control method for suppressing gas leak detection by a gas meter.

  A fuel cell device according to an embodiment of the present disclosure includes a hot module and a control unit. The hot module has a power generation state and a stop state. In the power generation state, the hot module generates power by causing a reforming reaction of gas supplied via a gas meter. The hot module does not generate power using the gas in the stopped state. The hot module transitions from the stopped state to the power generation state through a startup process state. The hot module makes a transition from the power generation state to the stop state through a stop processing state. The control unit causes the hot module to maintain the stopped state for a predetermined periodic stop period every predetermined cycle. When the hot module is in the stopped state other than the periodic stop period, the control unit causes the hot module to transition to the activation process state before the first predetermined time, and after the first predetermined time. Sometimes the hot module is not transitioned to the activation process state. The first predetermined time is a time that is back from the scheduled start time of the next periodic stop period by the total time of the time required for the activation process state and the time required for the stop process state.

  A control method according to an embodiment of the present disclosure includes a power generation state in which power is generated using hydrogen obtained by reforming a gas supplied via a gas meter, and a stop state in which power generation using the hydrogen is not performed. A control method of a fuel cell device comprising a hot module that transitions from the stop state to the power generation state through a start process state and from the power generation state to the stop state through a stop process state, When the module continues the stop state for a predetermined periodic stop period every predetermined cycle, and the hot module is in the stop state other than the periodic stop period, the start-up from the scheduled start time of the next periodic stop period The hot module is placed in the start-up processing state before a first predetermined time that is a sum of the time required for the processing state and the time required for the stop processing state. It moved so, when the first predetermined time after the not transition the hot module in the activation processing state.

  According to an embodiment of the present disclosure, a fuel cell device and a control method that suppress gas leak detection by a gas meter are realized.

It is a block diagram showing a schematic structure of a fuel cell device concerning one embodiment of this indication. It is a figure explaining operation | movement of a hot module. It is a figure (the 1) which shows the aspect in which a control part controls a hot module. It is FIG. (2) which shows the aspect which a control part controls a hot module. It is a flowchart which shows operation | movement of the fuel cell apparatus at the time of a power failure.

  Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings.

[Schematic Configuration of Fuel Cell Device 1]
As shown in FIG. 1, the fuel cell device 1 is provided in a customer facility such as a general household or a commercial and industrial facility. The fuel cell device 1 includes a pressure switch 11, a first electromagnetic valve 12a, a second electromagnetic valve 12b, a gas pump 13, a gas flow meter 14, a hot module 20, a power conditioner 30, and a storage unit 110. , Control unit 120, input unit 210, and timing unit 220. The hot module 20 includes a reforming unit 21 and a fuel cell unit 22. In FIG. 1, a solid line indicates a route such as gas, electric power, or water. An alternate long and short dash line indicates a communication path.

  The pressure switch 11 detects the pressure of the gas supplied through the external gas meter 60. The pressure switch 11 outputs a signal (contact signal) when detecting the set predetermined pressure.

  The first solenoid valve 12 a and the second solenoid valve 12 b are two gas solenoid valves that open and close the gas supply path to the hot module 20. The first solenoid valve 12a and the second solenoid valve 12b open and close the gas supply path using the force of the electromagnet. By arranging the first solenoid valve 12a and the second solenoid valve 12b in series, even if one gas solenoid valve fails and the gas supply cannot be stopped, the other gas solenoid valve is operated. Thus, the gas supply can be stopped more reliably. Three or more gas solenoid valves may be used.

  The gas pump 13 adjusts the flow rate of the gas supplied to the hot module 20 by swinging a diaphragm provided inside the pump head.

  The gas flow meter 14 is a flow meter for measuring the flow rate of the gas supplied to the hot module 20. The gas flow meter 14 measures the gas flow rate. The gas flow meter 14 transmits the measured gas flow rate information to the control unit 120 by wired communication or wireless communication.

  The reforming unit 21 of the hot module 20 generates hydrogen as fuel for the fuel cell from water and methane contained in the gas supplied via the gas meter 60. The reforming unit 21 causes a reforming reaction between water and methane to obtain a product (reformed gas) containing hydrogen. The reforming unit 21 is maintained at a temperature suitable for the reforming reaction by a heater.

  The fuel cell unit 22 of the hot module 20 includes one or more fuel cells. For example, the fuel cell unit 22 has a cell stack in which a plurality of fuel cells are stacked. The reformed gas is supplied from the reforming unit 21 to the fuel cell unit 22. Air is supplied to the fuel cell unit 22. The fuel cell unit 22 generates power using hydrogen in the reformed gas and oxygen in the air. Specifically, the fuel cell unit 22 reacts hydrogen and oxygen to generate water and electricity. The fuel cell unit 22 supplies the generated DC power to the power conditioner 30. The fuel cell unit 22 discharges high-temperature exhaust gas. The exhaust gas can contain, for example, hydrogen, carbon dioxide, carbon monoxide and the like in the reformed gas. The fuel cell unit 22 supplies the exhaust gas to the heat exchanger 40.

  The power conditioner 30 converts the DC power from the fuel cell unit 22 into AC power and outputs it. The power conditioner 30 supplies the converted AC power to the power load 82 via the distribution board 80. When the DC power from the fuel cell unit 22 is sufficiently supplied, the power conditioner 30 drives each component by supplying the DC power from the fuel cell unit 22 to each component of the fuel cell device 1. To do. On the other hand, when the DC power from the fuel cell unit 22 cannot be sufficiently secured, the power conditioner 30 converts AC power from the outside, for example, AC power from the system 81 into DC power. Then, the power conditioner 30 supplies the converted DC power to each component of the fuel cell device 1 to drive each component.

  The power conditioner 30 may perform so-called load following control in which output power is adjusted according to the power consumption of the power load 82. For example, the power conditioner 30 detects a current output from the hot module 20 and performs load following control based on the detected current. The power conditioner 30 transmits output power information to the control unit 120.

  The heat exchanger 40 is connected to the hot water tank 70 via the circulation path 41. The hot water tank 70 is provided in a customer facility. The water stored in the hot water tank 70 circulates in the circulation path 41 by, for example, a circulation pump. The heat exchanger 40 heats the water circulated between the hot water storage tank 70 via the circulation path 41 using the heat energy of the supplied exhaust gas.

  The storage unit 110 includes, for example, a primary storage device or a secondary storage device. The storage unit 110 includes, for example, a semiconductor memory, a magnetic memory, or an optical memory. The semiconductor memory includes, for example, a volatile memory or a nonvolatile memory. The magnetic memory includes, for example, a hard disk or a magnetic tape. The optical memory includes, for example, a CD (Compact Disc), a DVD (Digital Versatile Disc), or a BD (Blu-ray (registered trademark) Disc). The storage unit 110 stores various information and programs used for the operation of the fuel cell device 1.

  The control unit 120 has one or more processors. The processor includes a dedicated processor specialized for a specific process or a general-purpose processor that executes a specific function by reading a specific program. The control unit 120 controls the overall operation of the fuel cell device 1. Specifically, the control unit 120 controls the first electromagnetic valve 12a and the second electromagnetic valve 12b to start and stop the gas supply. Based on the gas flow rate information received from the gas flow meter 14, the control unit 120 controls the gas pump 13 to adjust the gas flow rate. The controller 120 controls the gas pump 13 based on the output power information received from the power conditioner 30 to adjust the gas flow rate.

  The storage unit 110 and the control unit 120 are configured as one control device 100, for example. The control device 100 is an arbitrary information processing device such as a computer.

  The input unit 210 receives input from the user. The input unit 210 includes, for example, an operation button or a touch panel.

  The timer unit 220 is a timer that measures time. The timer unit 220 is, for example, an RTC (Real Time Clock). The timer unit 220 may be implemented as a function of the control unit 120. The timer unit 220 may synchronize with time information received from a time server via a network.

  The input unit 210 and the time measuring unit 220 are configured as one remote controller 200, for example. The remote controller 200 exchanges signals with the control unit 120, for example, by wireless communication. The remote controller 200 is operated by a power source different from the configuration of the fuel cell device 1 other than the remote controller 200, for example. The remote controller 200 can be operated by a power source different from the configuration of the fuel cell device 1 other than the remote controller 200, so that the time count by the time measuring unit 220 can be maintained even during a power failure, for example.

  The gas meter 60 is a detector that detects the amount of gas supplied to the fuel cell device 1. The gas meter 60 detects the supply amount of gas per 30 seconds to 60 seconds, for example. When the gas supply amount satisfies a predetermined condition, the gas meter 60 determines that an abnormality has occurred in the gas supply and automatically shuts off the gas supply. Specifically, the gas meter 60 determines that a gas leak has occurred and shuts off the gas supply when it continuously detects a flow rate of gas above a predetermined level over a predetermined gas leak detection period (for example, 30 days). To do. The gas meter 60 resets the count of the gas leak detection period when the gas is continuously stopped for a predetermined gas leak detection cancellation period (for example, 10 hours).

[Operation of Fuel Cell Device 1]
FIG. 2 shows the flow rate of the gas supplied to the hot module 20 on the vertical axis, the passage of time on the horizontal axis, and the time change of the flow rate of the gas supplied to the hot module 20. As shown in FIG. 2, the hot module 20 has a power generation state S _{1 in} which power is generated by a reforming reaction of the gas supplied via the gas meter 60 and a stop state S _{2 in} which power generation using the gas is not performed. Have. The hot module 20 transitions from the stop state S ₂ to the power generation state S ₁ through the start processing state S ₃ . In the startup process state S ₃ , the gas flow rate gradually increases from the stop state S ₂ toward the power generation state S ₁ . The hot module 20 transitions from the power generation state S ₁ to the stop state S ₂ through the stop processing state S ₄ . Stopping the processing state S _4, toward the power generating state S ₁ in a stopped state S _2, and gradually the flow rate of the gas is decreased. Although FIG. 2 shows an example in which the time change of the gas flow rate in the start processing state S ₃ and the stop processing state S ₄ is a constant ratio, it may not be a constant ratio. Hereinafter, the start processing state S ₃ , the power generation state S ₁ , and the stop processing state S ₄ are collectively referred to as a start state.

As shown in FIG. 2, the hot module 20 needs to undergo a predetermined process such as heating of the reforming unit 21 in the startup process state S ₃ . Thus, activation processing state S ₃ requires a predetermined duration T ₃ (e.g., 4 hours 2 hours). Hot module 20, it is necessary to go through cooling or the like of the stop processing state S ₄ in the reforming unit 21, a predetermined process. Therefore, stop processing state S _4, the predetermined duration T ₄ (for example, 10 hours to 20 hours) required. The hot module 20 requires gas supplied via the gas meter 60 in the start processing state S ₃ and the stop processing state S ₄ . Hot module 20, in order to reduce the burden on the hot module 20, not immediately transition to the stop state S ₂ killed to the startup state, stop via a stop processing state S ₄ of the required time T ₄ states S from the transition to _2, a transition to the power generating state S ₁ through the activation processing state S ₃ of the required time T _3. Intercrural sex, transition for the same reason, the hot module 20 starts processing state S ₃ of the way instead of the transition to the stop processing state S _4, the power generation state S ₁ through the activation processing state S ₃ of the required time T ₃ After that, the process proceeds to the stop state S ₂ through the stop process state S ₄ of the required time T ₄ .

The control unit 120 causes the hot module 20 to maintain the stop state S ₂ for a predetermined periodic stop period T ₁ (for example, one day) every predetermined cycle. The control unit 120 allows the hot module 20 to be in the activated state during the activation state allowable period T ₂ (for example, 25 days, 26 days, or 27 days) that is a period other than the regular stop period T ₁ . The activation state allowable period T ₂ is a period shorter than the gas leak detection period of the gas meter 60. The regular stop period T ₁ is a period longer than the gas leak detection cancellation period of the gas meter 60.

When the hot module 20 is in the power generation state S ₁ at the second predetermined time B, the control unit 120 causes the hot module 20 to transition to the stop processing state S ₄ at the second predetermined time B. Thereafter, the control unit 120 performs reboot processing end time D of the next scheduled stop period T _1. In the restart process, the control unit 120 to transition the hot module 20 to start processing state S _3. The second predetermined time B is a time that goes back from the scheduled start time C of the next periodic stop period T ₁ to the required time T ₄ of the stop processing state S ₄ . Thus, the fuel cell system 1, when the hot module 20 at a second predetermined time B is a power generating state S _1, while in a stopped state S ₂ hot module 20 periodically stop period T _1, the power generation state S ₁ The maximum can be ensured.

As shown in FIG. 3, when the hot module 20 is not in the regular stop period T ₁ , that is, when the hot module 20 is in the stop state S ₂ in the start state allowable period T ₂ , when the hot module 20 is before the first predetermined time A, performing automatic startup process for transitioning a 20 to start processing state S _3. Hereinafter, the period before the first predetermined time A in the activation state allowable period T ₂ is also referred to as an automatic activation period T ₅ . On the other hand, when the hot module 20 is in the stop state S ₂ in the start state allowable period T ₂ , the control unit 120 does not transition the hot module 20 to the start processing state S ₃ after the first predetermined time A. Hereinafter, the period after the first predetermined time A in the activation state allowable period T ₂ is referred to as an activation prohibition period T ₆ . The first predetermined time A, the total time going back to the required time T ₃ of the activation processing state S ₃ from the scheduled start time C of the next regular stop period T ₁ and duration T ₄ of stop processing state S _4. In FIG. 3, the change over time in the gas flow rate when the transition is made from the stop state S ₂ to the start processing state S ₃ at the first predetermined time A is indicated by a broken line.

As described above, the fuel cell device 1 prohibits the transition to the activated state after the first predetermined time A when the hot module 20 is in the stopped state S ₂ during the activated state allowable period T ₂ . That is, the fuel cell apparatus 1, if it can not secure the required time T ₄ of the required time T ₃ and stop processing state S ₄ activation processing state S ₃ prohibits the hot module 20 transitions to start state. By doing so, even when the hot module 20 transitions to start state, and transitions to the stop state S ₂ through the stop processing state S ₄ of the required time T ₃ until the scheduled start time C of periodic stop period T _1. Therefore, the fuel cell device 1 can place the hot module 20 in the stop state S ₂ in the regular stop period T ₁ without imposing an excessive burden on the hot module 20.

Control unit 120, the via the input unit 210 is stop command hot module 20 is input transitions the hot module 20 in a stopped state S _2. Thereafter, the control unit 120 may perform control so as not to perform the restart process and the automatic start process. Thus, since the fuel cell apparatus 1 does not perform the restart process and the automatic start process when the stop command is input, it can follow the user's intention to stop power generation.

The stop command input via the input unit 210 may include a normal stop command and an emergency stop command. When the normal stop command is input, the control unit 120 causes the hot module 20 to transition to the stop state S ₂ through the stop processing state S ₄ . When an emergency stop command is input, the control unit 120 forcibly terminates the hot module 20 and immediately transitions to the stop state S ₂ without going through the stop processing state S ₄ regardless of the operation state of the hot module 20.

The control unit 120, the hot module 20 is abnormally stopped (e.g., stop by the abnormality detection of the gas pump 13) if a transition to the stop state S ₂ and restart the process and automatic activation processing may be controlled not performed. For example, when the gas flow rate received from the gas flow meter 14 is different from the prediction when the gas flow rate is adjusted by controlling the gas pump 13, the control unit 120 detects an abnormality in the gas pump 13. As described above, since the fuel cell device 1 does not perform the restart process and the automatic start process when the hot module 20 abnormally stops, safety can be ensured. Thereafter, when the safety can be ensured, for example, when information indicating that the safety is ensured is input via the input unit 210, the control unit 120 performs a restart process and an automatic start process. The control unit 120 causes the hot module 20 to transition to the stop state S ₂ through the stop processing state S ₄ due to a light failure that does not affect safety (for example, a communication failure between the control device 100 and the remote controller 200). May be controlled to perform a restart process and an automatic start process.

  With reference to FIGS. 4 and 5, the operation of the fuel cell device 1 when the power supply from the system 81 to the fuel cell device 1 is stopped, that is, when a power failure occurs will be described.

The hot module 20 is driven by external power, for example, power from the system 81 in an operation state other than the power generation state S ₁ . When the hot module 20 is not in the power generation state S ₁ at the time of the occurrence of a power failure (No in step S101), the hot module 20 cannot receive power supply and forcibly terminates (step S102). For example, if the hot module 20 is in the start processing state S ₃ or the stop processing state S ₄ at the time of the power failure, it is forcibly terminated and immediately transitions to the stop state S ₂ . On the other hand, when the hot module 20 is in the power generation state S ₁ at the time of the power failure (Yes in Step S101), the process proceeds to Step S103.

When the power failure occurrence time is before the third predetermined time E (No in Step S103), the fuel cell device 1 proceeds to the process of Step S104. The third predetermined time E is a time that is back from the second predetermined time B by a predetermined time T ₇ (for example, 3.5 hours). The predetermined time T ₇ is appropriately set to be longer than the time required for the system 81 to resume power supply, that is, to restore power.

When the fuel cell device 1 is restored by the second predetermined time B (Yes in step S104), the fuel cell device 1 shifts to normal power control, that is, the above-described power control (step S105). On the other hand, if not Fukuden until the second predetermined time B (No in step S104), and the hot module 20, kill, immediately transitions to the stop state S ₂ at the time of the second predetermined time B (step S102).

In the step S103, when the power failure occurrence time is after the third predetermined time E (Yes in step S103), the fuel cell device 1 proceeds to the step S106. If no Fukuden from power failure time within the predetermined time T ₇ (No in step S106), the hot module 20 forcibly terminated, a transition to the stop state S ₂ (step S102). On the other hand, when Fukuden from power failure time within the predetermined time T ₇ (Yes in step S106), the control unit 120 shifts the hot module 20 to stop processing state S ₄ (step S107).

According to the fuel cell apparatus 1 operating as described above, when a power failure occurs third predetermined time E after going back the predetermined time T ₇ above the time required for power recovery from the second predetermined time B, predetermined from the power failure If power is restored within time T ₇ , even if the second predetermined time B has passed, the control unit 120 causes the hot module 20 to transition to the stop processing state S ₄ . Therefore, the fuel cell apparatus 1, without imposing excessive burden on the hot module 20 after power restoration, it is possible to hot modules 20 in a stopped state S _2. In this case, there is a case where the stopped state S ₂ is less than a regular stop period T _1, the time obtained by subtracting the predetermined time T ₇ from regularly stop period T _1, longer than the gas leakage detection release period of the gas meter 60.

  The present invention is not limited to the configuration specified in the above-described embodiment, and various modifications can be made without departing from the scope of the invention described in the claims. For example, the functions included in each component, each step, etc. can be rearranged so that there is no logical contradiction, and a plurality of components, steps, etc. can be combined or divided into one It is. Further, although the present disclosure has been described focusing on the fuel cell device 1, the present disclosure can be realized as a method, a program, or a storage medium storing the program for controlling the fuel cell device 1 by a computer. It should be understood that these are included within the scope of the disclosure.

DESCRIPTION OF SYMBOLS 1 Fuel cell apparatus 11 Pressure switch 12a 1st solenoid valve 12b 2nd solenoid valve 13 Gas pump 14 Gas flow meter 20 Hot module 21 Reforming unit 22 Fuel cell unit 30 Power conditioner 40 Heat exchanger 41 Circulation path 60 Gas meter 70 Hot water tank 80 Distribution board 81 System 82 Power load 100 Control device 110 Storage unit 120 Control unit 200 Remote controller 210 Input unit 220 Timing unit A First predetermined time B Second predetermined time C Scheduled start time D of next periodic stop period Next Periodic stop period end time E Third predetermined time S ₁ Power generation state S ₂ Stop state S ₃ Startup process state S ₄ Stop process state T ₁ Periodic stop period T ₂ Startup state allowable period T ₃ Startup process state required time T ₄ Time required for the stop processing state T ₅ Automatic start period T ₆ Start prohibition period T ₇ Predetermined time

Claims (7)

It has a power generation state where power is generated by reforming a gas supplied via a gas meter, and a stop state where power generation using the gas is not performed, and transitions from the stop state to the power generation state via a startup process state And a hot module that transitions from the power generation state to the stop state through a stop processing state;
A control unit that causes the hot module to maintain the stop state for a predetermined periodic stop period for each predetermined period;
With
The control unit, when the hot module is in the stopped state other than the periodic stop period, calculates the required time in the startup process state and the required time in the stop process state from the scheduled start time of the next periodic stop period. The hot module is transitioned to the activation processing state before a first predetermined time that is traced back by the total time, and the hot module is not transitioned to the activation processing state after the first predetermined time.
Fuel cell device. When the hot module is in the power generation state at a second predetermined time that is a time required for the stop process state from a scheduled start time of a next periodic stop period, the control module is configured to output the hot module at the second predetermined time. To the stop processing state, to perform a restart process to transition the hot module to the start processing state at the end time of the next periodic stop period,
The fuel cell device according to claim 1. It further includes an input unit that receives input from the user,
When the hot module stop command is input to the input unit, the control unit causes the hot module to transition to the stop state, and performs the restart process even at the end time of the next periodic stop period. Absent,
The fuel cell device according to claim 2. When the hot module abnormally stops, the control unit does not perform the restart process even at the end time of the next periodic stop period.
The fuel cell device according to claim 2 or 3. The hot module is driven by external power in an operating state other than the power generation state,
The control unit includes the external module after the time when the hot module is in the power generation state and the total time of the time required for the stop processing state and a predetermined time is elapsed from the scheduled start time of the next periodic stop period. When the supply of power is stopped, the hot module is changed to the stop processing state when the external power supply is resumed within the predetermined time from the stop.
The fuel cell device according to any one of claims 1 to 4. The gas meter shuts off the gas supply when the gas supply continues for a predetermined period or longer.
The fuel cell device according to any one of claims 1 to 5. A power generation state in which power generation is performed using hydrogen obtained by reforming a gas supplied through a gas meter; and a stop state in which power generation using the hydrogen is not performed; A control method of a fuel cell device comprising a hot module that transitions to the power generation state and transitions from the power generation state to the stop state through a stop processing state,
Let the hot module continue the stop state for a predetermined periodic stop period every predetermined cycle,
When the hot module is in the stopped state other than the periodic stop period, the total time of the required time in the startup process state and the required time in the stop process state is traced back from the scheduled start time of the next periodic stop period The hot module is transitioned to the activation process state before a first predetermined time, and the hot module is not transitioned to the activation process state after the first predetermined time.
Control method.

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