JP5816842B2 - Gas leak detection system for fuel cell system - Google Patents

Description

  The present invention relates to a gas leak detection system for a fuel cell system, which is implemented for safety before starting power generation in a fuel cell system including a fuel cell device that generates power using fuel gas containing hydrocarbons.

  In recent years, awareness of conservation of the global environment has increased, and a fuel cell system including a fuel cell device capable of highly efficient power generation has attracted attention as an ecological product. The fuel cell system includes a polymer electrolyte fuel cell system having a fuel cell stack and a reformer as a fuel cell device, and an indirect internal reforming system in which the reformer and the fuel cell stack of the fuel cell device are integrated. Solid oxide fuel cell systems, direct internal reforming solid oxide fuel cell systems in which the fuel cell stack of the fuel cell device also has a reforming function, and the like.

  In such a fuel cell system, power is generated by supplying a fuel gas containing hydrogen and an oxidant gas containing oxygen to the fuel cell stack. In the case of household fuel cell systems, flammable city gas is often used as fuel gas, and it is necessary to check for gas leaks as a safety measure before generating electricity, etc. so that fuel gas does not leak from the source gas path There is.

  One known method for detecting a gas leak in a fuel cell system is to detect fuel gas leaked in the fuel cell system using a gas detection sensor (see, for example, Patent Document 1). In addition, a method of measuring a raw material gas flow rate and a raw material gas pressure in a raw material gas path using a raw material gas flow meter or a gas pressure gauge is also known (for example, see Patent Document 2).

  In the method using the raw material gas flow rate measuring device and the raw material gas pressure detector, it is easy to guess which raw material gas path is leaking in the measurement process, so it is used in combination with the gas detection sensor shown in Patent Document 1 or the like. Therefore, safety can be further improved. Conventionally, in the method using a raw material gas flow rate measuring device, gas leak detection is performed with the gas supply source open to increase the gas pressure in the raw material gas path, and the set fuel gas upper limit flow rate value is measured. It is judged that the gas leak is abnormal when

JP 2003-229148 A JP 2009-217951 A

  However, in the conventional configuration, since the gas supply source is opened when the gas leak of the fuel cell system is detected, the fuel cell system branches from the same gas pipe and simultaneously with other devices such as another fuel cell system or a gas heat pump. When used, it may be affected by pulsation of gas pressure due to operation of the device. When the pulsation of the gas pressure is transmitted to the source gas measurement mechanism that detects at least one of the flow rate and pressure of the source gas installed downstream of the source gas path of the source gas supplied to the fuel cell system, no gas flows. Even in this case, since the gas flow rate above a certain level is measured, it is erroneously detected as a gas leak, and the fuel cell system has a problem that power generation is disabled.

  The present invention solves the above-described conventional problems, and provides a gas leak detection system for a fuel cell system that can eliminate erroneous detection of gas leak and avoid an unnecessary power generation disabled state of the fuel cell system. With the goal.

In order to solve the above-described conventional problems, in the gas leak detection system for a fuel cell system according to the present invention, a gas leak detection system for a fuel cell system having a fuel cell device to which a raw material gas containing at least hydrocarbons is supplied. There,
A raw material gas measuring mechanism that is disposed in a raw material gas path of the raw material gas supplied to the fuel cell device, and includes a flow rate measuring device that measures the flow rate of the raw material gas and a pressure measuring device that measures the pressure of the raw material gas;
A first switch disposed in the source gas path upstream from the source gas measuring mechanism and configured to open and close the source gas path;
A second switch disposed in the source gas path downstream from the source gas measuring mechanism and configured to open and close the source gas path;
A controller for controlling the source gas measurement mechanism, the first switch, and the second switch;
have. Furthermore, the controller is
A first step of opening the first switch and closing the second switch to detect a gas leak from a flow rate value of the flow meter;
A second step of detecting a gas leak from the pressure value of the pressure measuring instrument with both said first switch and said second switch in a closed state after said first step,
A third step of detecting a gas leak from a flow rate value of the flow rate measuring device by closing both the first switch and the second switch after the second step;
To control.

Further, the gas leak detection method for a fuel cell system is a gas leak detection method for a fuel cell system having a fuel cell device to which a raw material gas containing at least hydrocarbons is supplied,
The upstream side of the source gas path of the source gas supplied to the fuel cell device is opened, the downstream side is closed, and the flow rate of the source gas between the opened upstream side and the closed downstream side is reduced. A first step of detecting a gas leak from the measured value;
After the first step, closes the closed upstream of the raw material gas path, detects a gas leak from the measured value of the pressure of the feed gas between the downstream and the closure and the closure to the upstream side A second step of:
After the second step, a third step of detecting a gas leak from a measured value of the flow rate of the source gas between the closed upstream side and the closed downstream side;
including.

  When “gas leak detection” is detected in the first step, the first switch and the second switch are both closed in the second step so that the gas fluid does not flow through the source gas path, and the source gas measurement mechanism By detecting the fluctuation of the measured value, it is possible to detect the presence or absence of gas leakage by eliminating the influence of gas pressure pulsation due to the operation of other devices. Thus, even when gas is not actually flowing, it is possible to avoid erroneous detection of “gas leak” by measuring a gas flow rate above a certain level due to the influence of pulsation of the gas pressure of other devices.

  Since the fuel cell system of the present invention can prevent erroneous detection of gas leakage due to gas pulsation when measuring the gas raw material gas flow rate in the fuel cell system, the fuel cell system cannot generate power due to an error due to erroneous detection. It can be avoided.

It is a block diagram which shows the whole structure of the gas leak detection system for fuel cell systems which concerns on Embodiment 1 of this invention. 3 is a flowchart of a gas leak detection method for a fuel cell system according to Embodiment 1. 5 is a flowchart of a gas leak detection method for a fuel cell system according to Embodiment 2.

A gas leak detection system for a fuel cell system according to a first aspect is a gas leak detection system for a fuel cell system having a fuel cell device to which a raw material gas containing at least hydrocarbons is supplied.
A raw material gas measuring mechanism that is disposed in a raw material gas path of the raw material gas supplied to the fuel cell device, and includes a flow rate measuring device that measures the flow rate of the raw material gas and a pressure measuring device that measures the pressure of the raw material gas;
A first switch disposed in the source gas path upstream from the source gas measuring mechanism and configured to open and close the source gas path;
A second switch disposed in the source gas path downstream from the source gas measuring mechanism and configured to open and close the source gas path;
A controller for controlling the source gas measurement mechanism, the first switch, and the second switch;
Consisting of
The controller is
A first step of opening the first switch and closing the second switch to detect a gas leak from a flow rate value of the flow meter;
A second step of detecting a gas leak from the pressure value of the pressure measuring instrument with both said first switch and said second switch in a closed state after said first step,
A third step of detecting a gas leak from a flow rate value of the flow rate measuring device by closing both the first switch and the second switch after the second step;
To control.
The controller may be one or more.

  According to the above configuration, the second switch is closed in the first step, and the gas fluid cannot flow downstream from the gas leak detection target path through the second switch. Therefore, as a raw material gas measurement mechanism with gas pressure applied to the raw material gas path, for example, when the raw material gas flow meter detects a flow rate higher than a certain level, the gas flows in the raw material gas path downstream from the raw material gas flow meter. Can detect leaks. On the other hand, since the first switch is opened for the purpose of increasing the gas pressure in the raw material gas path, the pulsation of the gas pressure due to the operation of other devices such as a gas heat pump branched and connected from the same gas pipe is described above. When affecting the fuel cell system, the gas fluid flows through the first switch. For this reason, even when no gas is flowing, since it is affected by pulsation in the raw material gas path, there is a possibility of detecting a flow rate above a certain level. Therefore, when a gas leak is detected in the first step, the cause can be caused by pulsation or a failure of the raw material gas flow rate measuring instrument in addition to the actual gas leak.

  Since both the first switch and the second switch are closed in the second step, the gas fluid cannot flow through the first switch, and the influence of pulsation upstream from the first switch Is blocked by the first switch. Therefore, it is possible to detect gas leakage without being affected by gas pulsation caused by a gas heat pump or the like in the raw material gas path. Therefore, when the second step is performed with the gas pressure on the source gas path and a gas leak is detected due to a gas pressure fluctuation exceeding a certain level, the cause is an actual gas leak or, for example, source gas measurement. It is a failure of the raw material gas pressure detector as a mechanism, and it can be determined that both are abnormal.

  In the third step, since the first switch and the second switch are both closed as in the second step, gas leakage can be detected without being affected by gas pulsation in the raw material gas path. . Therefore, if the third step is performed with the gas pressure on the source gas path and a gas leak is detected at a gas flow rate above a certain level, the cause is an actual gas leak or a failure of the source gas flow meter. It can be judged. However, in the third step, if the volume of the source gas path for detecting gas leak is small, the gas flow rate leaking from the source gas path may be smaller than the threshold flow rate for detecting gas leak. It is not enough to detect gas leaks in the process.

  Therefore, by combining the first, second, and third steps, gas leakage due to the influence of pulsation even when the fuel cell system and other devices such as a gas heat pump are connected by branching from the same gas pipe. Can be avoided.

The gas leak detection system for a fuel cell system according to a second aspect is the first aspect, wherein the raw material gas flow rate measuring device detects a flow rate above a certain level in a state in which the gas pressure is applied to the raw material gas path in the first step. In addition, when the pressure value of the raw material gas pressure detector does not fluctuate more than a certain value in the second step, the third step is performed.

  According to the above configuration, when a gas leak is detected in the first step and no gas leak is detected in the second step, there is no actual gas leak and the gas leak is detected in the first step. It can be determined that the detected cause is a pulsation or a failure of the raw material gas flow rate measuring device. Therefore, it is possible to determine whether the cause of the gas leakage detected in the first step is due to pulsation or the failure of the raw material gas flow rate measuring device by performing the third step under the conditions.

The gas leak detection system for a fuel cell system according to a third aspect is characterized in that, in the second aspect, if no gas leak is detected in the third step, it is determined that no gas leak has occurred. And

  According to the above configuration, when a gas leak is detected in the first step and no gas leak is detected in the second step, there is no actual gas leak and the gas leak is detected in the first step. It can be determined that the detected cause is a pulsation or a failure of the raw material gas flow rate measuring device. Therefore, when the gas leak is not detected in the third process that is not affected by the pulsation under the condition, it can be determined that the cause of the gas leak detected in the first process is due to the pulsation. Therefore, the fuel cell system does not erroneously detect a gas leak due to the influence of gas pressure pulsation caused by the operation of another device such as a gas heat pump, and can avoid an unnecessary power generation disabled state.

The gas leak detection system for a fuel cell system according to the fourth aspect determines that the raw material gas flow rate measuring device has failed when the gas leak is detected in the third step in the second aspect. Features.

  According to the above configuration, when a gas leak is detected in the first step and no gas leak is detected in the second step, there is no actual gas leak and the gas leak is detected in the first step. It can be determined that the detected cause is a pulsation or a failure of the raw material gas flow rate measuring device. Therefore, if a gas leak is detected in the third process that is not affected by the pulsation under that condition, it is determined that the cause of the gas leak detected in the first process is due to a failure of the raw material gas flow meter. And an abnormal power generation state can be avoided.

A fuel cell system according to a fifth aspect includes the gas leak detection system for a fuel cell system according to any one of the first to fourth aspects.

A gas leak detection method for a fuel cell system according to a sixth aspect includes:
A gas leak detection method for a fuel cell system having a fuel cell device to which a source gas containing at least hydrocarbons is supplied,
The upstream side of the source gas path of the source gas supplied to the fuel cell device is opened, the downstream side is closed, and the flow rate of the source gas between the opened upstream side and the closed downstream side is reduced. A first step of detecting a gas leak from the measured value;
After the first step, closes the closed upstream of the raw material gas path, detects a gas leak from the measured value of the pressure of the feed gas between the downstream and the closure and the closure to the upstream side A second step of:
After the second step, a third step of detecting a gas leak from a measured value of the flow rate of the source gas between the closed upstream side and the closed downstream side;
including.

A fuel leak detection program for a fuel cell system according to a seventh aspect is configured by instructions that cause a computer to execute each step of the gas leak detection method for a fuel cell system according to the sixth aspect.

A computer-readable recording medium according to the eighth aspect stores a gas leak detection program for a fuel cell system according to the seventh aspect.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Note that the present invention is not limited by the present embodiment.

(Embodiment 1)
First, the configuration of the fuel cell system 1 according to Embodiment 1 of the present invention will be described with reference to FIG. FIG. 1 is a block diagram schematically showing the configuration of a fuel cell system 1 according to Embodiment 1 of the present invention. Further, FIG. 1 shows only components necessary for explaining the present invention, the source gas path branched in a complicated manner in the fuel cell system 1 is simplified to one, and other components are omitted. doing. The fuel cell system 1 includes a raw material gas path 15 that supplies a raw material gas to the fuel cell device, a hydrogen generator 20, a fuel cell stack 21, and a fuel cell system gas leak detection system.

This gas leak detection system for a fuel cell system is disposed in the raw material gas path 15 and is disposed in the raw material gas measurement mechanism 23 for measuring the pressure or flow rate of the raw material gas, and the raw material gas path 15 upstream from the raw material gas measurement mechanism 23. The first switch 10 that opens and closes the source gas path 15 to control the gas inflow into the source gas path 15 and the source gas path 15 downstream from the source gas measurement mechanism 23 are disposed in the source gas path 15. The second switch 13 that opens and closes and controls gas outflow from the source gas path 15 is electrically connected to the source gas measuring mechanism 23, the first switch 10 and the second switch 13, and each device And a controller 14 for controlling. The source gas measuring mechanism 23 includes a flow rate measuring device 11 that measures the flow rate of the source gas and a pressure measuring device 12 that measures the pressure of the source gas. In addition, the controller 14 has a function of opening and closing the first switch 10 and the second switch 13 and controlling the open and closed states necessary when detecting a gas leak in the raw material gas path 15. The controller 14 also receives values measured by the flow rate measuring device 11 and the pressure measuring device 12. The first switch 10 and the second switch 13 are, for example, electronic on-off valves and the like, and may be devices that can at least open and close the source gas path 15.
In FIG. 1, the hydrogen generator 20 and the fuel cell stack 21 are illustrated between the upstream first switch 10 and the downstream second switch 13 in the source gas path 15. This is an example, and the present invention is not limited to these. The present invention is not limited to the above example, and a device or the like for which gas leakage is to be detected may be appropriately sandwiched between the upstream first switch 10 and the downstream second switch 13.

  In FIG. 1, in addition to the fuel cell system 1, for example, gas equipment such as a gas heat pump 2 is branched and connected from a raw material gas pipe 3 which is a supply source of raw material gas. When the gas heat pump 2 shown in FIG. 1 is operated, gas pressure pulsation of the raw material gas pipe 3 is generated by the operation of the gas heat pump 2 and affects the raw material gas path 15 of the fuel cell system 1. Therefore, when the fuel cell system 1 and other devices are used simultaneously from the same raw material gas pipe 3, a gas leak detection system that eliminates the influence of gas pressure pulsation that has not been considered so far in the control means of the controller 14 is provided. is necessary.

  In the gas leak detection system for a fuel cell system according to Embodiment 1, a first opening / closing operation is performed upstream of the source gas path 15 where a gas leak is to be detected (in FIG. 1, the hydrogen generator 20 and the stack 21). A source gas measuring mechanism 23 for measuring at least one of the flow rate or the pressure of the source gas between the first switch 10 and a location where gas leakage is to be detected is provided on the downstream side of the vessel 10. Provided. Further, by controlling the opening and closing of the first switch 10 and the second switch 13, the first step S 100 and the second step S 101 are performed, and gas leakage is detected based on the measured value by the source gas measuring mechanism 23. Detected.

  Next, a characteristic gas leak detection method of the gas leak detection system for a fuel cell system according to Embodiment 1 will be described with reference to FIG.

FIG. 2 is a flowchart showing the flow of the gas leak detection method according to Embodiment 1 of the present invention.
(A) In the first step S100, the controller 14 opens the first switch 10 and closes the second switch 13 to check whether or not there is a gas leak in a state where the gas flows into the raw material gas path 15. Check. In the first step S100, since the gas pressure is applied to the raw material gas path 15, when there is a gas leak, the flow rate meter 11 detects a flow rate value equal to or higher than the first flow rate value stored in advance. Will do. On the other hand, if the flow rate measuring device 11 does not detect a flow rate value equal to or higher than the first flow rate value stored in advance, it can be determined that there is no gas leakage, so the state of the fuel cell system 1 is shifted to the power generation possible state S107. To do. Note that the first flow rate value is a flow rate that flows when a gas leak occurs in the raw material gas path 15, and can be arbitrarily determined through experiments or simulations depending on the structure of the raw material gas path 15 or the configuration of the fuel cell system. it can.

  However, if it is determined in the first step S100 that a gas leak has occurred, a flow rate fluctuation due to the effect of gas pressure pulsation due to the operation of the gas heat pump 2 may be erroneously detected as a gas leak. It is necessary to shift the state of the battery system 1 to the temporary power generation disabled state S103 and examine the gas leakage abnormality in more detail.

(B) The second step S101 is another step in the gas leak detection method performed by the controller 14 when it is determined in the first step S100 that there is a gas leak. Since the second step S101 is performed after the first step, the first switch 10 and the second switch 13 are closed in a state where the gas pressure is applied into the source gas path 15, and the state is maintained for a certain time. Even if kept, the presence or absence of gas leakage is confirmed by confirming whether the measured value of the pressure measuring instrument 12 does not drop below the first pressure value stored in advance. The first pressure value is a pressure value of the raw material gas that is lowered when a gas leak occurs in the raw material gas path 15. Experiments, simulations, and the like are performed depending on the structure of the raw material gas path 15 and the configuration of the fuel cell system 1. Can be determined arbitrarily.

  In the second step S101, since the first switch 10 and the second switch 13 are closed, they are not affected by the gas pressure pulsation due to the operation of the gas heat pump 2. Therefore, also in the second step S101, if a gas leak is detected, there is a suspicion of a gas leak or failure of the pressure measuring instrument 12. Therefore, gas leakage confirmation S104 is performed, and the state of the fuel cell system is shifted from the temporary power generation disabled state S103 to the power generation disabled state S106, which is an abnormal state.

Moreover, when the pressure measuring device 12 does not fall more than a 1st pressure value, it can be judged that there is no gas leak. When it is determined that there is no gas leakage, the process proceeds to the power generation possible state S107 and ends.
According to the gas leak detection method for a fuel cell system according to the first embodiment, when “gas leak” is detected in the first step S100, the second step S101 is further executed and “gas leak” is performed again. Is detected, “Gas Leak Determination S104” is set. Therefore, it is possible to prevent erroneous detection of gas leakage, avoid unnecessary power generation disabled state S106, and are useful for improving the operating efficiency and quality of the fuel cell system 1.

  Note that the gas leak detection method for a fuel cell system according to Embodiment 1 may be a gas leak detection program for a fuel cell system configured by instructions for causing each step to be executed by a computer. Furthermore, the gas leak detection program for the fuel cell system may be stored in a computer-readable recording medium.

  In FIG. 1, the second on-off valve 13 is disposed in the source gas path 15 on the downstream side of the stack 21, but is not limited thereto. Depending on the path in which gas leakage is to be detected, for example, the raw material gas path 15 between the hydrogen generator 20 and the stack 21, and the raw material downstream of the flow meter 11 and pressure meter 12 and upstream of the hydrogen generator 20. It may be arranged in at least one of the gas paths 15. A plurality of second on-off valves 13 may be arranged.

Moreover, although the structure which arrange | positions the pressure measuring device 12 downstream from the flow measuring device 11 was demonstrated, you may arrange | position the pressure measuring device 12 upstream from the flow measuring device 11.
Further, the first step S100 and the second step S101 may be performed sequentially or sequentially, or other operations such as opening the first switch 10 and the second switch 13 are opened during each step. Such control may be performed. Further, in the second step and the third step, the source gas pressure in the source gas path 15 between the first switch 10 and the second switch 13 only needs to be equal to or higher than the pressure value at which gas leakage can occur.
In addition, the flow measuring device 11 is used in the first step S100 and the pressure measuring device 12 is used in the second step S101. However, in the second step S101 using the pressure measuring device 12 in the first step S100. A flow meter 11 may be used.

(Embodiment 2)
The gas leak detection system for a fuel cell system according to Embodiment 2 is compared with the gas leak detection system for a fuel cell system according to Embodiment 1 with respect to the operation in the controller 14 in the first step S100 and the second step. In addition to the step S101, the third step S102 is different. In addition, 3rd process S102 is demonstrated in the flowchart of the gas leak detection method for the following fuel cell systems.

FIG. 3 is a flowchart of a gas leak detection method for a fuel cell system according to Embodiment 2. In this flowchart, the first step S100 and the second step S101 are the same as the first step S100 and the second step S101, as compared with the gas leak detection method for the fuel cell system according to the first embodiment. The description of step S101 will be omitted.
When the fuel leak detection method for a fuel cell system according to Embodiment 2 is compared with the gas leak detection method for a fuel cell system according to Embodiment 1, following the first step S100 and the second step S101, further The difference is that the third step S102 is executed. In the second embodiment, even if it is determined in the second step S101 that “no gas leak”, the third step S102 is further executed, so that “there is a gas leak” in the first step S100. It is possible to confirm the reason for determining “no gas leakage” in the second step S101, and to prevent “gas leakage” from being overlooked.

In the gas leak detection method for a fuel cell system according to Embodiment 1, when it is determined that there is no gas leak in the second step S101, the process proceeds to the power generation possible state S107 and ends.
However, after the first step S100, the reason why the gas leakage was detected in the first step S100 that caused the second step S101 to be executed is the influence of pulsation due to the operation of the gas heat pump 2, or the flow rate. It is necessary to check whether or not the failure is a measuring instrument failure S106. At this time, the state of the fuel cell system 1 continues the temporary power generation disabled state S103.

In the gas leak detection method for a fuel cell system according to Embodiment 2, when it is determined that there is no gas leak in the second step S101, the third step S102 is performed thereafter.
(C) The third step S102 is another step of the method for detecting a gas leak performed by the controller 14 when the second step S101 does not determine that there is a gas leak. Specifically, the first switch 10 and the second switch 13 are closed in a state in which the gas pressure is applied into the raw material gas passage 15, and the flow rate measuring device 11 stores in advance even if the state is maintained for a certain period of time. The presence or absence of gas leakage is confirmed by checking whether or not the gas flow rate equal to or greater than the second flow rate value is not measured. The second flow rate value is a flow rate measured when the flow rate measuring device 11 breaks down, and can be arbitrarily determined by experiments or simulations depending on the type of the flow rate measuring device.

  In the third step S102, since the first switch 10 and the second switch 13 are closed, they are not affected by the gas pressure pulsation due to the operation of the gas heat pump 2. Therefore, if gas leakage is detected in the third step S102, there is a suspicion of failure of the flow rate measuring device 11, so it is determined that the flow rate measuring device 11 has failed S105 and the state of the fuel cell system 1 is abnormal. As described above, the temporary power generation disabled state S103 is shifted to the power generation disabled state S106. In this case, the controller 14 may display an error on a remote controller or the like, and may restart the fuel cell system 1 itself, or may cause the fuel cell system 1 to stop processing.

  Moreover, when the flow rate measuring device 11 does not detect a gas flow rate above a certain level, it can be determined that there is no gas leakage. Therefore, it can be determined that the cause of the gas leak detected in the first step S100 is the influence of pulsation due to the operation of the gas heat pump 2, so the state of the fuel cell system 1 is changed from the temporary power generation disabled state S103 to the power generation enabled state S107. Transition.

  Therefore, even when a gas leak abnormality is detected in the first step S100, the cause of the gas leak abnormality being detected by performing the second step S101 and the third step S102 is due to the gas leak. It can be specified whether it is due to the influence of gas pressure pulsation due to the operation of equipment such as the heat pump 2 or due to a failure of the flow rate measuring device 11. Therefore, unnecessary power generation disabled state S106 can be avoided, which is useful for improving the operating efficiency and quality of the fuel cell system.

  In FIG. 1, the second on-off valve 13 is disposed in the source gas path 15 on the downstream side of the stack 21, but is not limited thereto. Depending on the path in which gas leakage is to be detected, for example, the raw material gas path 15 between the hydrogen generator 20 and the stack 21, and the raw material downstream of the flow meter 11 and pressure meter 12 and upstream of the hydrogen generator 20. It may be arranged in at least one of the gas paths 15. A plurality of second on-off valves 13 may be arranged.

Moreover, although the structure which arrange | positions the pressure measuring device 12 downstream from the flow measuring device 11 was demonstrated, you may arrange | position the pressure measuring device 12 upstream from the flow measuring device 11.
Furthermore, the first step, the second step, and the third step may be performed sequentially or sequentially, or other operations such as the first switch 10 and the second switch are performed during each step. Control that opens 13 may be performed. Further, in the second step and the third step, the source gas pressure in the source gas path 15 between the first switch 10 and the second switch 13 only needs to be equal to or higher than the pressure value at which gas leakage can occur.

  As described above, the fuel cell system according to the present invention can eliminate the influence of gas pressure pulsation due to the operation of other devices when a device such as a gas heat pump is connected to the same source gas supply source. Therefore, it is useful as a household fuel cell system.

DESCRIPTION OF SYMBOLS 1 Fuel cell system 2 Gas heat pump 3 Raw material gas piping 10 1st switch 11 Flow rate measuring device (raw material gas measurement mechanism)
12 Pressure measuring device (raw material gas measuring mechanism)
13 Second switch 14 Controller 15 Raw material gas path 20 Hydrogen generator 21 Stack 22 Case 23 Raw material gas measurement mechanism

Claims (8)

A gas leak detection system for a fuel cell system having a fuel cell device to which a source gas containing at least hydrocarbons is supplied,
A raw material gas measuring mechanism that is disposed in a raw material gas path of the raw material gas supplied to the fuel cell device, and includes a flow rate measuring device that measures the flow rate of the raw material gas and a pressure measuring device that measures the pressure of the raw material gas;
A first switch disposed in the source gas path upstream from the source gas measuring mechanism and configured to open and close the source gas path;
A second switch disposed in the source gas path downstream from the source gas measuring mechanism and configured to open and close the source gas path;
A controller for controlling the source gas measurement mechanism, the first switch, and the second switch;
Have
The controller is
A first step of opening the first switch and closing the second switch to detect a gas leak from a flow rate value of the flow meter;
A second step of detecting a gas leak from the pressure value of the pressure measuring instrument with both said first switch and said second switch in a closed state after said first step,
A third step of detecting a gas leak from a flow rate value of the flow rate measuring device by closing both the first switch and the second switch after the second step;
A gas leak detection system for a fuel cell system that controls the fuel cell system. The controller is
In the first step, the flow rate measured by the flow rate measuring instrument measures a flow rate value equal to or higher than the first flow rate value stored in advance, and in the second step, the measured pressure of the pressure measuring instrument is stored in advance. If you did not decreased are first or pressure value, the third step performs the gas leakage detection system for a fuel cell system according to claim 1. The controller is
The third when said measured flow of the flow rate measuring device does not measure the second flow rate value or more flow value stored in advance in the step, it is determined that gas leakage has not occurred, to claim 2 The gas leak detection system for fuel cell systems as described. The controller is
3. The fuel according to claim 2 , wherein in the third step, it is determined that a gas leak has occurred when the flow rate measured by the flow meter measures a flow rate value equal to or higher than a second flow rate value stored in advance. Gas leak detection system for battery systems. A fuel cell system comprising the fuel leak detection system for a fuel cell system according to any one of claims 1 to 4 . A gas leak detection method for a fuel cell system having a fuel cell device to which a source gas containing at least hydrocarbons is supplied,
The upstream side of the source gas path of the source gas supplied to the fuel cell device is opened, the downstream side is closed, and the flow rate of the source gas between the opened upstream side and the closed downstream side is reduced. A first step of detecting a gas leak from the measured value;
After the first step, closes the closed upstream of the raw material gas path, detects a gas leak from the measured value of the pressure of the feed gas between the downstream and the closure and the closure to the upstream side A second step of:
After the second step, a third step of detecting a gas leak from a measured value of the flow rate of the source gas between the closed upstream side and the closed downstream side;
A gas leak detection method for a fuel cell system, comprising: A gas leak detection program for a fuel cell system configured by instructions for causing a computer to execute each step of the gas leak detection method for a fuel cell system according to claim 6 . A computer-readable recording medium in which the gas leak detection program for the fuel cell system according to claim 7 is stored.

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