JP6758399B2 - How to detect abnormalities in fuel cell devices and current sensors - Google Patents

Description

Cross reference to related applications

This application claims the priority of Japanese Patent Application No. 2016-23768 (filed October 31, 2016), and the entire disclosure of the application is incorporated herein by reference.

The present disclosure relates to a method for detecting an abnormality in a fuel cell device and a current sensor.

In recent years, the number of consumer facilities where fuel cell devices are installed is increasing. In many cases, contracts between consumer facilities and electric power companies do not allow the output current of fuel cell devices to reverse power to the commercial power system (hereinafter abbreviated as "power system"). Therefore, when the fuel cell device is connected to the power system, a current sensor for detecting the current flowing between the fuel cell device and the power system is provided.

The current sensor is manually installed by the installer. At this time, the installer may make a mistake in the mounting direction of the current sensor. Further, if the mounting strength of the current sensor is insufficient, the current sensor may fall off due to an external factor such as an earthquake after the current sensor is installed.

In this way, if the current sensor is installed in the opposite direction or the current sensor falls off, the current sensor cannot normally detect the reverse power flow from the fuel cell device to the power system, and the fuel cell. Backfeeding from the device to the power system may not be prevented. Therefore, a method of detecting an abnormality of a current sensor in a fuel cell device has been proposed (Patent Document 1). In the method described in Patent Document 1, the output of the fuel cell device is fluctuated by the inverter to fluctuate the value detected by the current sensor. After that, an abnormality of the current sensor is detected based on the amount of fluctuation of the value detected by the current sensor.

Japanese Unexamined Patent Publication No. 2010-250945

The fuel cell device according to the embodiment of the present disclosure includes an auxiliary device including a heater and a control unit. The control unit detects an abnormality in the current sensor based on a detected value flowing from the power system to the auxiliary machine, which is detected by the current sensor when the auxiliary machine is in an operating state. The control unit detects an abnormality of the current sensor based on the detected value and a reference value detected by the current sensor when the auxiliary machine is in a non-operating state. When the control unit determines that the detected value is below the threshold value, the control unit puts the heater in the operating state into the non-operating state. The threshold value is a value obtained by adding a reference value detected by the current sensor when the heater is in the non-operating state to the rated current value of the switch located between the heater and the power system.

The method for detecting an abnormality of the current sensor according to the embodiment of the present disclosure is a step of operating an auxiliary machine including a heater, and the method of detecting the current sensor when the auxiliary machine is in an operating state from the power system. It includes a step of detecting an abnormality of the current sensor based on the detected value flowing through the auxiliary machine. The method of detecting the abnormality of the current sensor includes a step of detecting the abnormality of the current sensor based on the detected value and a reference value detected by the current sensor when the auxiliary machine is in a non-operating state. When it is determined that the detected value is below the threshold value, the step of putting the heater in the operating state into the non-operating state is included. The threshold value is a value obtained by adding a reference value detected by the current sensor when the heater is in the non-operating state to the rated current value of the switch located between the heater and the power system.

It is a figure which shows the schematic structure of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a figure which shows an example of the time dependence of the current value flowing through a heater. It is a flowchart which shows an example of the operation of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a flowchart which shows an example of the operation of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a figure which shows an example of the table which shows the relationship between the current value flowing through a heater, and the standby time of a heater when the rated current value of a switch is 10A. It is a flowchart which shows an example of the operation of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a figure which shows the schematic structure of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a figure which shows an example of the table which shows the relationship between the current value flowing through a heater, and the standby time of a heater when the rated current value of a switch is 5A. It is a flowchart which shows an example of the operation of the fuel cell apparatus which concerns on one Embodiment of this disclosure. It is a flowchart which shows an example of the operation of the fuel cell apparatus which concerns on one Embodiment of this disclosure.

In the conventional method, the output of the fuel cell device is fluctuated by the inverter. Therefore, the process for detecting an abnormality in the current sensor becomes complicated due to the control process of the inverter or the like.

According to the method for detecting an abnormality in the fuel cell device and the current sensor according to the embodiment of the present disclosure, the abnormality in the current sensor can be easily detected.

Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings.

(First Embodiment)
FIG. 1 shows a schematic configuration of a fuel cell device 1 according to an embodiment of the present disclosure. In FIG. 1, the solid line indicates the power line, and the broken line indicates the control line and the signal line. The fuel cell device 1 is installed in, for example, a consumer facility. The fuel cell device 1 is connected to the power system 100. In the following, it is assumed that the contract between the consumer facility and the electric power company (electric power system 100) does not allow the output current of the fuel cell device 1 to be reverse-flowed to the electric power system 100.

The fuel cell device 1 is a device that generates electricity by an electrochemical reaction of fuel. The fuel cell device 1 is, for example, SOFC (Solid Oxide Fuel Cell) or PEFC (Polymer Electrolyte Fuel Cell). The fuel cell device 1 supplies the generated electric power to the general load 4. Details of the configuration of the fuel cell device 1 will be described later.

The remote controller 2 is used by the user when setting the amount of power generation of the fuel cell device 1 and the like. When the current sensor 3 is abnormal, the remote controller 2 receives a signal from the fuel cell device 1 indicating that the current sensor 3 is abnormal. When the remote controller 2 receives a signal indicating that the current sensor 3 is abnormal, the remote controller 2 displays a warning indicating that the current sensor 3 is not functioning properly and presents it to the user.

The current sensor 3 is provided between the fuel cell device 1 and the power system 100. The current sensor 3 detects the value of the current flowing between the fuel cell device 1 and the power system 100. The current sensor 3 transmits the detected value to the fuel cell device 1.

The general load 4 is a load device installed in a consumer facility. The general load 4 consumes at least one of the electric power supplied from the fuel cell device 1 and the electric power supplied from the electric power system 100. The general load 4 is an electric product including, for example, a refrigerator and a dryer.

The fuel cell device 1 includes a power generation unit 10 including a cell stack 11, an auxiliary device 12, a power conversion unit 20, a switch 30, a communication unit 40, a storage unit 50, and a control unit 60.

The cell stack 11 generates DC electric power from the fuel supplied from the auxiliary machine 12 (for example, gas, air, and reformed water mixed in a predetermined ratio). The cell stack 11 supplies the generated DC power to the power conversion unit 20.

The auxiliary machine 12 is a peripheral device necessary for generating electricity in the cell stack 11. The auxiliary machine 12 supplies fuel to the cell stack 11. The auxiliary machine 12 includes, for example, a heater 13, a blower 15, a pump 16, a fan 17, and the like.

The heater 13 includes, for example, a combustion catalyst heater for heating the combustion catalyst, a heater used for preventing freezing of condensed water, a heater used for igniting fuel, and the like.

The blower 15 includes, for example, an air blower that sends air to the power generation unit 10. The blower 15 can be driven by the electric power supplied from the electric power system 100. The blower 15 may be driven by the electric power supplied from the fuel cell device 1.

The pump 16 includes a gas pump that sends gas to the power generation unit 10, a reformed water pump that sends reformed water to the power generation unit 10, and the like. The pump 16 can be driven by the electric power supplied from the electric power system 100. The pump 16 may be driven by the electric power supplied from the fuel cell device 1.

The fan 17 includes a ventilation fan or the like that ventilates the inside of the fuel cell device 1. The fan 17 can be driven by the electric power supplied from the electric power system 100. The fan 17 may be driven by the electric power supplied from the fuel cell device 1.

The power conversion unit 20 converts the DC power supplied from the power generation unit 10 into AC power. The power conversion unit 20 supplies the converted AC power to the general load 4 and the like.

The switch 30 includes, for example, a relay. The switch 30 is provided between the heater 13 and the power system 100. The control unit 60 switches between an open state and a closed state of the switch 30. When the switch 30 is closed, the heater 13 is in the operating state. When the switch 30 is opened, the energization of the heater 13 is stopped, and the heater 13 is in a non-operating state. Further, when the heater 13 is in the operating state, the auxiliary machine 12 may also be in the operating state. Further, when the heater 13 is in the non-operating state, the auxiliary machine 12 may also be in the non-operating state.

The communication unit 40 communicates with the remote controller 2. Further, the communication unit 40 can communicate with a remote server or the like via a network.

The storage unit 50 stores information necessary for processing of the fuel cell device 1 and a program describing processing contents for realizing each function of the fuel cell device 1. In the present embodiment, the storage unit 50 stores, for example, a threshold value and the like described later.

The control unit 60 controls and manages the entire fuel cell device 1. The control unit 60 is composed of any suitable processor such as a general-purpose CPU (central processing unit) that has read software for executing processing of each function. Alternatively, the control unit 60 is configured by, for example, a dedicated processor specialized in processing each function.

In the present embodiment, the control unit 60 detects an abnormality of the current sensor 3 based on a current value (hereinafter, referred to as “detection value”) detected by the current sensor 3 when the auxiliary machine 12 is in the operating state. Hereinafter, an example in which the control unit 60 detects an abnormality of the current sensor 3 based on a detection value which is a current value detected by the current sensor 3 when the heater 13 is in an operating state will be described. The details of this process will be described in the following <Process for detecting an abnormality in the current sensor>.

Further, the control unit 60 puts the auxiliary machine 12 in the operating state into the non-operating state based on the current value flowing through the auxiliary machine 12. Hereinafter, an example in which the control unit 60 sets the operating heater 13 to the non-operating state based on the current value flowing through the heater 13 will be described. The details of this process will be described in the following <Process for setting the heater to a non-operating state>.

The control unit 60 may detect an abnormality in the current sensor 3 by using at least one of the blower 15, the pump 16, and the fan 17 included in the auxiliary machine 12 instead of the heater 13. In this case, the control unit 60 detects an abnormality in the current sensor 3 based on a detection value which is a current value detected by the current sensor 3 when at least one of the blower 15, the pump 16, and the fan 17 is in the operating state. .. Further, in this case, the control unit 60 puts at least one of the blower 15, the pump 16, and the fan 17 in the operating state into the non-operating state based on the detected value.

<Processing to detect abnormalities in the current sensor>
The control unit 60 opens the switch 30 and puts the heater 13 in a non-operating state. Further, the control unit 60 acquires a current value (hereinafter, referred to as “reference value”) detected by the current sensor 3 when the heater 13 is in the non-operating state. The heater 13 does not consume power when it is in a non-operating state. Therefore, the reference value is the current value flowing from the power system 100 to the general load 4.

The control unit 60 closes the switch 30 and operates the heater 13. Further, the control unit 60 acquires a current value (detection value) detected by the current sensor 3 when the heater 13 is in the operating state. The heater 13 consumes electric power when it is in an operating state. Therefore, the detected value is the sum of the current value flowing from the power system 100 to the general load 4 and the current value flowing from the power system 100 to the heater 13.

The control unit 60 inspects the current sensor 3 based on the reference value and the detected value. The obtained inspection result of the current sensor 3 includes, for example, that the mounting direction of the current sensor 3 is correct, the mounting direction of the current sensor 3 is opposite, and the current sensor 3 is dropped off. Hereinafter, an example of processing by the control unit 60 when inspecting the current sensor 3 will be described.

(1) Processing for inspecting the current sensor The reference value is the current value flowing from the power system 100 to the general load 4 as described above. On the other hand, the detected value is a value obtained by adding the current value flowing from the power system 100 to the general load 4 and the current value flowing from the power system 100 to the heater 13 as described above. That is, if the mounting direction of the current sensor 3 is correct, the detected value will be larger than the reference value.

Therefore, when the control unit 60 determines that the detected value is larger than the reference value, the control unit 60 obtains the inspection result of the current sensor 3 that the mounting direction of the current sensor 3 is correct. When the control unit 60 determines that the detected value is larger than the sum of the reference value and the predetermined value, the control unit 60 may obtain the inspection result of the current sensor 3 that the mounting direction of the current sensor 3 is correct. Further, when the control unit 60 determines that the detected value is smaller than the reference value, the control unit 60 obtains an inspection result of the current sensor 3 that the mounting direction of the current sensor 3 is opposite. When the control unit 60 determines that the detected value is smaller than the value obtained by subtracting the predetermined value from the reference value, the control unit 60 may obtain the inspection result of the current sensor 3 that the mounting direction of the current sensor 3 is opposite. Further, when the control unit 60 determines that the detected value and the reference value are equivalent, the control unit 60 obtains an inspection result of the current sensor 3 that the current sensor 3 has fallen off. In this case, when the control unit 60 determines that the difference between the detected value and the reference value is within a predetermined value, the control unit 60 may determine that the detected value and the reference value are equivalent.

When the heater 13 is in the operating state, a current obtained by adding the current flowing from the power system 100 to the general load 4 and the current flowing from the power system 100 to the heater 13 flows through the current sensor 3. Therefore, when the heater 13 is in the operating state, if the mounting direction of the current sensor 3 is correct, the control unit 60 detects the forward current from the power system 100 by the current sensor 3. Therefore, when the control unit 60 determines that reverse power flow to the power system 100 is generated from the polarity of the detected value, even if the control unit 60 outputs the inspection result of the current sensor 3 that the mounting direction of the current sensor 3 is opposite. Good. In this way, the control unit 60 can output the inspection result of the current sensor 3 based on at least the detected value.

The reference value and the detected value include the current value flowing from the power system 100 to the general load 4. Further, the power consumed by the general load 4 may fluctuate with time. Therefore, the timing of acquiring the reference value and the detected value by the control unit 60 should be as close as possible. In this way, the current value flowing from the power system 100 included in the reference value to the general load 4 and the current value flowing from the power system 100 included in the detected value to the general load 4 become close to each other. Therefore, the control unit 60 can inspect the current sensor 3 with higher accuracy. In order to achieve this, the control unit 60 may acquire the reference value and the detected value, respectively, at the timing before and after switching the switch 30 from the open state to the closed state or from the closed state to the open state, for example. The timing of acquiring the reference value and the detected value may be set manually.

The control unit 60 determines whether or not the current sensor 3 is abnormal based on the inspection result of the current sensor 3 obtained by the process (1) described above. Hereinafter, an example of processing by the control unit 60 when determining whether or not the current sensor 3 is abnormal will be described.

(2) Process for determining whether the current sensor is abnormal First, the control unit 60 repeats the process (1) described above to obtain a first predetermined number of inspection results of the current sensor 3. Next, the control unit 60 determines whether or not the current sensor 3 is abnormal based on the inspection results of the first predetermined number of the current sensors 3. For example, the control unit 60 determines that the current sensor 3 is abnormal when the result of a predetermined ratio or more of the inspection results of the first predetermined number of the current sensor 3 is the result that the mounting direction of the current sensor 3 is opposite. judge. The predetermined ratio is, for example, 75%. Further, for example, when the control unit 60 has a result of a predetermined ratio or more of the inspection results of the first predetermined number of the current sensors 3 that the current sensor 3 has fallen off, the current sensor 3 is abnormal. Judge that there is. Alternatively, for example, when the result of the predetermined ratio or more of the inspection results of the first predetermined number of the current sensor 3 is the result that the mounting direction of the current sensor 3 is correct, the control unit 60 is abnormal in the current sensor 3. It may be determined that there is no current sensor 3, that is, the current sensor 3 is normal.

The control unit 60 may determine that the current sensor 3 is abnormal when a second predetermined number of inspection results indicating that the current sensor 3 is abnormal are continuously obtained. For example, the control unit 60 may determine that the current sensor 3 is abnormal when a second predetermined number of inspection results indicating that the current sensor 3 is attached in the opposite direction are continuously obtained. Further, for example, the control unit 60 may determine that the current sensor 3 is abnormal when a second predetermined number of inspection results indicating that the current sensor 3 has fallen off are continuously obtained. Alternatively, the control unit 60 determines that the current sensor 3 is not abnormal, that is, the current sensor 3 is normal, when a second predetermined number of inspection results indicating that the mounting direction of the current sensor 3 is correct are continuously obtained. You may.

When the control unit 60 determines that the current sensor 3 is abnormal, the control unit 60 transmits a signal to the remote controller 2 that the current sensor 3 is abnormal via the communication unit 40. When the remote controller 2 receives a signal from the fuel cell device 1 that the current sensor 3 is abnormal, the remote controller 2 displays a warning indicating that the current sensor 3 is not functioning properly and presents it to the user.

The control unit 60 may transmit a signal indicating that the current sensor 3 is abnormal and a signal indicating the type of abnormality of the current sensor 3 to the remote controller 2 via the communication unit 40. For example, when the inspection result of the first predetermined number of the current sensor 3 includes the result that the mounting direction of the current sensor 3 is opposite, the control unit 60 uses the current as a signal indicating the type of abnormality of the current sensor 3. A signal indicating that the mounting direction of the sensor 3 is opposite may be transmitted. Further, for example, when the inspection result of the first predetermined number of the current sensor 3 includes the result that the current sensor 3 has fallen off, the control unit 60 uses the current as a signal indicating the type of abnormality of the current sensor 3. A signal indicating that the sensor 3 has fallen off may be transmitted.

<Processing to put the heater in a non-operating state>
Next, the details of the processing of the control unit 60 when the heater 13 in the operating state is put into the non-operating state will be described. First, the characteristics of the current value flowing through the heater will be described with reference to FIG.

FIG. 2 shows an example of the time dependence of the current value flowing through the heater. In FIG. 2, the vertical axis shows the current value flowing through the heater, and the horizontal axis shows the operating time (operating time) of the heater. The time 0 [s] corresponds to the timing at which the heater starts operating. Further, in FIG. 2, the portion indicated by hatching indicates a range of current values that can be taken by the alternating current flowing through the heater. Further, in FIG. 2, as an example, the time dependence of the current value flowing through the combustion catalyst heater is shown.

The temperature of the heater depends on the operating time of the heater. The longer the heater is operating, the greater the temperature rise of the heater. Further, the shorter the operating time of the heater, the smaller the temperature rise of the heater. Further, the resistance value of the heater depends on the temperature of the heater. The lower the temperature of the heater, the smaller the resistance value of the heater. Further, the higher the temperature of the heater, the larger the resistance value of the heater. Therefore, as the operating time of the heater increases, the temperature rise of the heater increases, and as a result, the resistance value of the heater increases. Therefore, the longer the operating time of the heater, the smaller the current value flowing through the heater, as shown in FIG. Further, the shorter the operating time of the heater, the smaller the temperature rise of the heater, and as a result, the resistance value of the heater becomes smaller. Therefore, the shorter the operating time of the heater, the larger the current value flowing through the heater, as shown in FIG.

Here, if the current value flowing through the heater 13 is large, the current value flowing through the switch 30 is also large. If the control unit 60 repeatedly switches between the closed state and the open state of the switch 30 when the current value flowing through the switch 30 is large, the deterioration of the switch 30 may progress. However, from another point of view, when the current value flowing through the switch 30 is small, if the control unit 60 repeatedly switches between the closed state and the open state of the switch 30, the degree of deterioration of the switch 30 can be reduced. ..

Therefore, in the present embodiment, when the value of the current flowing through the heater 13 is small, the heater 13 in the operating state is put into the non-operating state. As a result, when the value of the current flowing through the heater 13 is small, the switch 30 is switched from the closed state to the open state. An example of the processing at this time will be described below.

First, the control unit 60 acquires the current value detected by the current sensor 3 when the heater 13 is in the operating state. Further, the control unit 60 uses the acquired current value to determine whether or not the current value flowing through the heater 13 is small enough to reduce the degree of deterioration of the switch 30. For example, the control unit 60 determines whether or not the acquired current value is equal to or greater than the threshold value.

For example, the threshold value can be a value obtained by adding the above-mentioned reference value (current value flowing from the power system 100 to the general load 4) to the rated current value of the switch 30. This is based on the fact that the current value acquired by the control unit 60 at this time is the same as the detected value acquired when detecting the abnormality of the current sensor 3. As described above, the detected value is a value obtained by adding the current value flowing from the power system 100 to the general load 4 and the current value flowing to the heater 13. Therefore, the threshold value is set to, for example, the value obtained by adding the above-mentioned reference value (current value flowing from the power system 100 to the general load 4) to the rated current value of the switch 30. Then, by determining whether or not the acquired current value is equal to or greater than the threshold value, it can be determined whether or not the current value flowing through the heater 13 is less than the rated current value of the switch 30. If the current value flowing through the heater 13 is lower than the rated current value of the switch 30, the degree of deterioration of the switch can be reduced. Of course, the threshold is not limited to this. For example, the threshold value may be a value obtained by adding the rated current value of the switch 30, a reference value, and a predetermined margin value.

When the control unit 60 determines that the acquired current value is below the threshold value, the control unit 60 opens the switch 30 and stops the energization of the heater 13.

On the other hand, when the control unit 60 determines that the acquired current value is equal to or greater than the threshold value, the control unit 60 acquires the current value detected by the current sensor 3 again. The control unit 60 continues to acquire the current value detected by the current sensor 3 until it determines that the acquired current value is below the threshold value.

[System operation]
Hereinafter, an example of the operation of the fuel cell device 1 according to the embodiment of the present disclosure will be described with reference to FIGS. 3 and 4.

First, the control unit 60 opens the switch 30 and acquires a reference value (step S101). Next, the control unit 60 closes the switch 30 and operates the heater 13 (step S102). Further, the control unit 60 acquires the detected value (step S103).

The control unit 60 inspects the current sensor 3 based on the reference value acquired in the process of step S101 and the detected value acquired in the process of step S103 (step S104). For example, the control unit 60 inspects the current sensor 3 by the process of (1) described above.

By the processing of steps S101 to S103, the reference value and the detected value are acquired before and after the control unit 60 switches the switch 30 from the open state to the closed state, respectively. As a result, the current value flowing from the power system 100 included in the reference value to the general load 4 and the current value flowing from the power system 100 included in the detected value to the general load 4 become close to each other. Therefore, the control unit 60 can inspect the current sensor 3 with higher accuracy in the process of step S104.

The control unit 60 acquires the current value detected by the current sensor 3 (step S105). Further, the control unit 60 determines whether or not the acquired current value is equal to or greater than the threshold value (step S106). When the control unit 60 determines that the acquired current value is equal to or greater than the threshold value (step S106: Yes), the control unit 60 repeats the process from step S105. On the other hand, when the control unit 60 determines that the acquired current value is below the threshold value (step S106; No), the control unit 60 proceeds to the process of step S107.

In the process of step S107, the control unit 60 acquires the detected value. Further, the control unit 60 opens the switch 30 and stops the energization of the heater 13 (step S108).

When it is determined that the acquired current value is below the threshold value by the processing of steps S105 to S108, the control unit 60 opens the switch 30. As a result, when the value of the current flowing through the switch 30 is small, the switch 30 is switched from the closed state to the open state. Therefore, the degree of deterioration of the switch 30 can be reduced.

The control unit 60 acquires a reference value (step S109). Further, the control unit 60 inspects the current sensor 3 in the same manner as in the process of step S104, based on the reference value acquired in the process of step S109 and the detected value acquired in the process of step S107 (step S110).

By the processing of steps S107 to S109, the detection value and the reference value are acquired before and after the control unit 60 switches the switch 30 from the closed state to the open state, respectively. As a result, the current value flowing from the power system 100 included in the reference value to the general load 4 and the current value flowing from the power system 100 included in the detected value to the general load 4 become close to each other. Therefore, the control unit 60 can inspect the current sensor 3 with higher accuracy in the process of step S110.

The description of the flowchart shown in FIG. 4 proceeds.

The control unit 60 determines whether or not the first predetermined number of inspection results of the current sensor 3 has been obtained (step S111). When the control unit 60 determines that the first predetermined number of the inspection results of the current sensor 3 has been obtained (step S111: Yes), the control unit 60 proceeds to the process of step S112. On the other hand, when the control unit 60 determines that the first predetermined number of inspection results of the current sensor 3 has not been obtained (step S111: No), the control unit 60 returns to the process of step S101 shown in FIG. The temperature of the heater 13 has risen to some extent due to the processing of step S102 for the first time. Therefore, in the process of step S102 performed again, the switch 30 is switched to the closed state when the current value flowing through the heater 13 is small to some extent. Therefore, the degree of deterioration of the switch 30 can be reduced.

In the process of step S112, the control unit 60 determines whether or not the current sensor 3 is abnormal based on the inspection results of the first predetermined number of the current sensors 3. For example, the control unit 60 determines whether or not the current sensor 3 is abnormal by the process (2) described above. When the control unit 60 determines that the current sensor 3 is abnormal based on the inspection results of the first predetermined number of the current sensors 3 (step S112: Yes), the control unit 60 proceeds to the process of step S113. On the other hand, when the control unit 60 determines that the current sensor 3 is not abnormal (that is, the current sensor 3 is normal) based on the inspection results of the first predetermined number of the current sensors 3 (step S112: No), the process To finish.

In the process of step S113, the control unit 60 transmits a signal to the remote controller 2 that the current sensor 3 is abnormal via the communication unit 40. When the remote controller 2 receives a signal from the fuel cell device 1 that the current sensor 3 is abnormal, the remote controller 2 displays a warning indicating that the current sensor 3 is not functioning properly and presents it to the user.

Here, the control unit 60 may determine that the current sensor 3 is abnormal when a second predetermined number of inspection results indicating that the mounting directions of the current sensors 3 are opposite are continuously obtained. In this case, in the process of step S111, the control unit 60 determines whether or not a second predetermined number of inspection results indicating that the mounting directions of the current sensors 3 are opposite are continuously obtained. Further, when the control unit 60 determines that the second predetermined number of the inspection results indicating that the mounting directions of the current sensors 3 are opposite are continuously obtained, the control unit 60 determines that the current sensor 3 is abnormal, and in step S113, Proceed to processing. Similarly, the control unit 60 may determine that the current sensor 3 is abnormal when a second predetermined number of inspection results indicating that the current sensor 3 has fallen off are continuously obtained.

Further, the control unit 60 determines that the current sensor 3 is not abnormal (that is, the current sensor 3 is normal) when a second predetermined number of inspection results indicating that the mounting direction of the current sensor 3 is correct are continuously obtained. You may. In this case, in the process of step S111, the control unit 60 determines whether or not a second predetermined number of inspection results indicating that the mounting direction of the current sensor 3 is correct are continuously obtained. Further, the control unit 60 ends the process when it is determined that a second predetermined number of inspection results indicating that the mounting direction of the current sensor 3 is correct are continuously obtained.

Further, in order to make the inspection result of the current sensor obtained by the process of step S104 or the like more reliable, the heater 13 may be a heater having a large load. For example, the heater 13 may be a combustion catalyst heater. When the load of the heater 13 is large, the current value flowing through the heater 13 becomes large. Therefore, when the load of the heater 13 is large, the difference between the reference value acquired in the process of step S101 and the like and the detection value acquired in the process of step S103 and the like becomes large. As a result, the inspection result of the current sensor 3 obtained by the process of step S104 or the like becomes more reliable.

As described above, in the fuel cell device 1 according to the first embodiment, the control unit 60 is used to detect an abnormality of the current sensor 3 by simply setting the heater 13 in the non-operating state and the operating state. And the detected value can be acquired. Therefore, in the fuel cell device 1 according to the first embodiment, the control unit 60 can easily detect the abnormality of the current sensor 3.

Further, in the fuel cell device 1 according to the first embodiment, when the control unit 60 determines that the current value flowing through the heater 13 is below the threshold value, the control unit 60 puts the heater 13 in the operating state into the non-operating state. This makes it possible to prevent the control unit 60 from switching the switch 30 when the current flowing through the heater 13 is large. Therefore, in the fuel cell device 1 according to the first embodiment, the degree of deterioration of the switch 30 can be reduced.

In addition, in the fuel cell device 1 according to the present embodiment, the dedicated load for detecting the abnormality of the current sensor 3 is not built in the fuel cell device 1, but the heater 13 included in the fuel cell device 1 is used. To. As a result, in the fuel cell device 1, it is possible to prevent the configuration of the fuel cell device 1 from becoming complicated due to the provision of a dedicated load.

Further, the fuel cell device 1 according to the present embodiment can automatically detect an abnormality of the current sensor 3 as described above. Therefore, the installer does not have to bring a device or the like for confirming the mounting direction of the current sensor 3 in order to install the current sensor 3 when installing the fuel cell device 1. Therefore, in the present embodiment, the installer can efficiently install the fuel cell device 1.

Further, the fuel cell device 1 according to the present embodiment can automatically detect an abnormality of the current sensor 3 even after the current sensor 3 is installed. Therefore, the fuel cell device 1 according to the present embodiment can detect an abnormality even if an abnormality occurs in the current sensor 3 after the current sensor 3 is installed. For example, even if the installer correctly installs the current sensor, a third party may install the current sensor in the wrong direction due to the construction of the power line later. Further, for example, when the current sensor is of a clamp type, for example, the current sensor may fall off due to deterioration of the claws for closing and opening the movable core due to aging or other changes over time. That is, according to the fuel cell device 1 according to the present embodiment, such a situation can be detected.

Here, in order for the control unit 60 to switch the switch 30 when the current flowing through the heater 13 is small, as a comparative example, after the control unit 60 operates the heater 13, a sufficiently long time predetermined. It is assumed that the heater 13 is put into a non-operating state after the lapse of time. Generally, when detecting an abnormality in the current sensor, the control unit 60 acquires a current value by causing the current sensor to repeat an operating state and a non-operating state a plurality of times in order to reliably detect the abnormality in the current sensor. To do. Therefore, as in the method according to the comparative example, when the control unit 60 operates the heater 13 and then puts the heater 13 in the non-operating state every time after a sufficiently long time elapses for a predetermined period of time, It can take a lot of time.

On the other hand, in the present embodiment, when the control unit 60 determines that the current value detected by the current sensor 3 is below the threshold value, the control unit 60 puts the heater 13 in the operating state into the non-operating state. That is, the time from when the control unit 60 operates the heater 13 to when it is not operated is appropriately controlled according to the current value flowing through the heater 13. Thereby, in the present embodiment, the time required for the control unit 60 to detect the abnormality of the current sensor 3 can be appropriately controlled. Therefore, in the present embodiment, the control unit 60 can efficiently detect the abnormality of the current sensor 3.

In the present embodiment, a case where the auxiliary machine 12 in the operating state is put into the non-operating state has been described based on the current value flowing through the auxiliary machine 12 (heater 13). However, the method according to the present embodiment can also be applied to the case where the auxiliary machine 12 in the non-operating state is put into the operating state based on the current value flowing through the auxiliary machine 12.

(Second Embodiment)
Next, the fuel cell device according to the second embodiment will be described. The fuel cell device according to the second embodiment can adopt the same configuration as the fuel cell device according to the first embodiment. Therefore, in the following, the differences from the first embodiment will be mainly described with reference to FIG.

The second embodiment is different from the first embodiment in the processing of the control unit 60 when the heater 13 in the operating state is put into the non-operating state. In the second embodiment, the control unit 60 sets the standby time after the heater 13 is put into an operating state. The standby time is a time for the heater 13 to stand by in an operating state until the current value flowing through the heater 13 falls below the rated current value of the switch 30. The control unit 60 puts the heater 13 in the operating state into the non-operating state after the set standby time has elapsed. Hereinafter, an example of processing by the control unit 60 when setting the standby time will be described.

The control unit 60 subtracts a reference value from the detected value to calculate the current value flowing through the heater 13. The control unit 60 sets the standby time of the heater 13 based on the calculated current value flowing through the heater 13 and the rated current value of the switch 30. For example, the control unit 60 sets the standby time of the heater 13 by using the calculated current value flowing through the heater 13 and a table showing the relationship between the current value flowing through the heater 13 and the standby time of the heater 13.

FIG. 5 shows an example of a table showing the relationship between the current value flowing through the heater 13 and the standby time of the heater 13 when the rated current value of the switch 30 is 10A. The table shown in FIG. 5 is created, for example, based on the time dependence of the current value flowing through the heater 13 as shown in FIG. The left column of the table shows the value of the current flowing through the heater 13. The right column of the table shows the standby time of the heater 13 when the current value flowing through the heater 13 is the value shown in the left column.

In FIG. 5, the control unit 60 selects a value equivalent to the calculated current value flowing through the heater 13 from the left column. For example, the control unit 60 selects 40A from the left column when the calculated current value of the heater 13 is 39A. Next, the control unit 60 sets the time corresponding to the value in the selected left column as the operating time of the heater 13. For example, the control unit 60 sets the standby time of the heater 13 to 30 seconds when the value in the selected left column is 40A. In this way, when the control unit 60 causes the heater 13 to stand by in the operating state for the selected operating time, the current value flowing through the heater 13 thereafter becomes lower than the rated current value 10A of the switch 30.

[System operation]
Hereinafter, an example of the operation of the fuel cell device 1 according to the embodiment of the present disclosure will be described with reference to FIG. Since the processing of steps S201 to S204 is the same as the processing of steps S101 to 104 shown in FIG. 3, the description thereof will be omitted. Further, the processing after step S210 is the same as the processing of steps S111 to S113 shown in FIG.

The control unit 60 subtracts the reference value acquired in the process of step S201 from the detected value acquired in the process of step S203 to calculate the current value flowing through the heater 13. The control unit 60 sets the standby time of the heater 13 based on the calculated current value flowing through the heater 13 and the rated current value of the switch 30 (step S205). For example, the control unit 60 sets the standby time of the heater 13 by using the calculated current value flowing through the heater 13 and the table shown in FIG.

The control unit 60 determines whether or not the set waiting time has elapsed (step S206). When the control unit 60 determines that the set waiting time has elapsed (step S206: Yes), the control unit 60 proceeds to the process of step S207. On the other hand, when it is determined that the set waiting time has not elapsed (step S206: No), the control unit 60 repeats the process of step S206.

The control unit 60 performs the processes of steps S207 to S210 in the same manner as the processes of steps S107 to S110 shown in FIG.

In the fuel cell device 1 according to the second embodiment, other effects and functions are the same as those in the fuel cell device 1 according to the first embodiment.

(Third Embodiment)
Next, the fuel cell device 1a according to the third embodiment will be described. Hereinafter, the differences from the fuel cell device 1 according to the first and second embodiments will be mainly described.

FIG. 7 shows a schematic configuration of the fuel cell device 1a according to the embodiment of the present disclosure. Among the components shown in FIG. 7, the same components as those shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

The fuel cell device 1a according to the third embodiment controls the power generation unit 10 including the cell stack 11, the auxiliary equipment 12a, the power conversion unit 20, the switches 30, 31, the communication unit 40, and the storage unit 50. A unit 60 is provided. The auxiliary machine 12a includes heaters 13, 14, a blower 15, a pump 16, a fan 17, and the like.

The switch 31 includes, for example, a relay. The switch 31 is provided between the heater 14 and the power system 100. The control unit 60 switches between an open state and a closed state of the switch 31. When the switch 31 is closed, the heater 14 is put into operation. When the switch 31 is opened, the energization of the heater 14 is stopped, and the heater 14 is in a non-operating state.

The auxiliary machine 12a includes a heater (first heater) 13 and a heater (second heater) 14. The heater 14 is a heater different from the heater 13. In the following, it is assumed that the heater 13 has a longer standby time than the heater 14, for example, when the heaters 13 and 14 have the same temperature. In this case, for example, the heater 13 is a combustion catalyst heater, and the heater 14 is a heater used for igniting fuel.

FIG. 8 shows an example of a table showing the relationship between the current value flowing through the heater 14 and the standby time of the heater 14 when the rated current value of the switch 31 is 5A. The table shown in FIG. 8 is created based on the time dependence of the current value flowing through the heater 14, as in FIG. For example, when the heaters 13 and 14 have the same temperature, the current value flowing through the heater 13 is 40A, and the current value flowing through the heater 14 is 15A. At this time, the standby time of the heater 13 is 30 seconds as shown in FIG. On the other hand, the standby time of the heater 14 is 15 seconds as shown in FIG.

In the first and second embodiments, the control unit 60 uses one heater 13 to detect an abnormality in the current sensor 3. On the other hand, in the third embodiment, the control unit 60 detects an abnormality in the current sensor 3 by using two heaters, the heater 13 and the heater 14. More specifically, the control unit 60 acquires the inspection result (hereinafter, referred to as “first inspection result”) of the current sensor 3 by the heater 13. Further, the control unit 60 acquires the inspection result (hereinafter, referred to as “second inspection result”) of the current sensor 3 by the heater 14. In addition, the control unit 60 acquires the inspection result (hereinafter referred to as “third inspection result”) of the current sensor 3 by the heater 13 and the heater 14. After that, the control unit 60 detects the abnormality of the current sensor 3 based on the first inspection result, the second inspection result, and the third inspection result in the same manner as in the first embodiment. Hereinafter, an example of processing of the control unit 60 when acquiring the first inspection result, the second inspection result, and the third inspection result will be described.

When acquiring the first inspection result, first, the control unit 60 maintains the heater 14 in an operating state or a non-operating state. Next, the control unit 60 acquires a current value (hereinafter, referred to as “first reference value”) detected by the current sensor 3 when the heater 13 is in the non-operating state. Further, the control unit 60 acquires a current value (hereinafter, referred to as “first detected value”) detected by the current sensor 3 when the heater 13 is in the operating state. After that, the control unit 60 inspects the current sensor 3 based on the first reference value and the first detected value, and acquires the first inspection result, as in the first embodiment.

When acquiring the second inspection result, first, the control unit 60 maintains the heater 13 in an operating state or a non-operating state. Next, the control unit 60 acquires the current value (hereinafter, referred to as “second reference value”) detected by the current sensor 3 when the heater 14 is in the non-operating state. Further, the control unit 60 acquires a current value (hereinafter, referred to as “second detected value”) detected by the current sensor 3 when the heater 14 is in the operating state. After that, the control unit 60 inspects the current sensor 3 based on the second reference value and the second detected value, and acquires the second inspection result, as in the first embodiment.

When acquiring the third inspection result, the control unit 60 acquires the current value (hereinafter, referred to as “third reference value”) detected by the current sensor 3 when the heaters 13 and 14 are in the non-operating state. Further, the control unit 60 acquires a current value (hereinafter, referred to as “third detected value”) detected by the current sensor 3 when the heaters 13 and 14 are in the operating state. After that, the control unit 60 inspects the current sensor 3 based on the third reference value and the third detected value, and acquires the third inspection result, as in the first embodiment.

As described above, in the third embodiment, the control unit 60 combines the two heaters 13 and 14 to acquire the inspection result of the current sensor 3. Therefore, in the third embodiment, the abnormality of the current sensor 3 can be detected more efficiently.

Further, in the third embodiment, both the heaters 13 and 14 are set to the non-operating state or the operating state, and the third reference value and the third detected value are acquired. The difference between the third reference value and the third detection value obtained by the two heaters 13 and 14 is larger than the difference between the detection value and the reference value obtained by one heater. As a result, the third inspection result becomes more reliable. Therefore, in the third embodiment, the control unit 60 can inspect the current sensor 3 with higher accuracy.

In addition, in the third embodiment, the control unit 60 operates the heater 13 having a longer standby time before the heater 14 to acquire the above-mentioned first reference value and the like. Hereinafter, an example of the processing of the control unit 60 at this time will be described.

First, the control unit 60 opens the switches 30 and 31 to put the heaters 13 and 14 into a non-operating state. Next, the control unit 60 closes the switch 30 and operates the heater 13 after acquiring the first reference value. At this time, the heater 13 is in the operating state and the heater 14 is in the non-operating state. After that, the control unit 60 acquires the first detected value.

In this way, the control unit 60 operates the heater 13 before the heater 14. Further, the first reference value and the first detected value in this case are acquired by keeping the heater 14 in the non-operating state and the operating state while maintaining the heater 14 in the non-operating state.

After that, the control unit 60 sets the standby time of the heater 13 as in the second embodiment. For example, the control unit 60 subtracts the first reference value from the first detection value to calculate the current value flowing through the heater 13. Further, the control unit 60 sets the standby time of the heater 13 based on the calculated current value flowing through the heater 13 and the rated current value of the switch 30.

Further, after acquiring the second reference value, the control unit 60 closes the switch 31 and operates the heater 14. At this time, both the heaters 13 and 14 are in the operating state. After that, the control unit 60 acquires the second detected value. In this case, the second reference value and the second detected value are acquired by keeping the heater 13 in the operating state and keeping the heater 14 in the non-operating state and the operating state.

In addition, the control unit 60 acquires a third detection value when it determines that the set standby time of the heater 13 has elapsed. After that, the control unit 60 opens the switch 30 to stop the energization of the heater 13, and opens the switch 31 to stop the energization of the heater 14. At this time, both the heaters 13 and 14 are in the non-operating state. After that, the control unit 60 acquires the third reference value.

As described above, in the third embodiment, the control unit 60 operates the heater 13 having a long standby time before the heater 14 to acquire the first reference value and the like. Thereby, in the third embodiment, the control unit 60 can detect the abnormality of the current sensor 3 more efficiently.

[System operation]
Hereinafter, an example of the operation of the fuel cell device 1 according to the third embodiment of the present disclosure will be described with reference to FIGS. 9 and 10. The processing after step S314 shown in FIG. 10 is the same as the processing in steps S111 to S113 shown in FIG.

First, the control unit 60 acquires the first reference value (step S301). Next, the control unit 60 closes the switch 30 and operates the heater 13 (step S302). Further, the control unit 60 acquires the first detected value (step S303).

The first reference value acquired by the process of step S301 and the first detected value acquired by the process of step S303 are acquired by keeping the heater 13 in the non-operating state and the operating state while maintaining the heater 14 in the non-operating state. Will be done.

The control unit 60 inspects the current sensor 3 based on the first reference value acquired in the process of step S301 and the first detection value acquired in the process of step S303 (step S304). As a result, the control unit 60 acquires the first inspection result.

The control unit 60 subtracts the first reference value acquired in the process of step S301 from the first detection value acquired in the process of step S303 to calculate the current value flowing through the heater 13. The control unit 60 sets the standby time of the heater 13 based on the calculated current value flowing through the heater 13 and the rated current value of the switch 30 (step S305).

The control unit 60 acquires the second reference value (step S306). Next, the control unit 60 closes the switch 31 and operates the heater 14 (step S307). At this time, both the heaters 13 and 14 are in the operating state. The control unit 60 acquires the second detected value (step S308).

The second reference value acquired by the process of step S306 and the first detected value acquired by the process of step S308 are acquired by keeping the heater 14 in the non-operating state and the operating state while maintaining the heater 13 in the non-operating state. Will be done.

The control unit 60 inspects the current sensor 3 based on the second reference value acquired in the process of step S306 and the second detected value acquired in the process of step S308 (step S309). As a result, the control unit 60 acquires the second inspection result.

The description of the flowchart shown in FIG. 10 proceeds.

The control unit 60 determines whether or not the waiting time set in the process of step S305 shown in FIG. 9 has elapsed (step S310). When the control unit 60 determines that the set waiting time has elapsed (step S310: Yes), the control unit 60 proceeds to the process of step S111. On the other hand, when it is determined that the set standby time has not elapsed (step S310: No), the control unit 60 repeats the process of step S310.

In the process of step S311, the control unit 60 acquires the third detected value. Next, the control unit 60 opens the switch 30 to stop the energization of the heater 13, and opens the switch 31 to stop the energization of the heater 14 (step S312). After that, the control unit 60 acquires the third reference value (step S313).

The control unit 60 inspects the current sensor 3 based on the third detected value acquired in the process of step S111 and the third reference value acquired in the process of step S313 (step S314). As a result, the control unit 60 acquires the third inspection result.

As described above, in the third embodiment, the control unit 60 combines the two heaters 13 and 14 to acquire the inspection result of the current sensor 3. Therefore, in the third embodiment, the abnormality of the current sensor 3 can be detected more efficiently.

Further, in the third embodiment, the control unit 60 sets both the heaters 13 and 14 in the non-operating state or the operating state, and acquires the third reference value and the third detected value. The difference between the third reference value and the third detection value obtained by the two heaters 13 and 14 is larger than the difference between the detection value and the reference value obtained by one heater. As a result, the third inspection result becomes more reliable. Therefore, in the third embodiment, the control unit 60 can inspect the current sensor 3 with higher accuracy.

In addition, in the third embodiment, the control unit 60 operates the heater 13 having a long standby time before the heater 14 to acquire the first reference value and the like. Thereby, in the third embodiment, the abnormality of the current sensor 3 can be detected more efficiently.

In the fuel cell device 1a according to the third embodiment, other effects and functions are the same as those of the fuel cell device 1 according to the first and second embodiments.

Many aspects of this disclosure are presented as a series of actions performed by a computer system or other hardware capable of executing program instructions. Computer systems and other hardware include, for example, general purpose computers, PCs (Personal Computers), dedicated computers, workstations, PCSs (Personal Communications Systems), electronic notepads, laptop computers or other programmable. Data processing equipment is included. In each embodiment, various operations are performed by dedicated circuits implemented in program instructions (software) (eg, individual logic gates interconnected to perform specific functions), or by one or more processors. Note that it is executed by a logic block or program module that is executed. One or more processors that execute a logical block or a program module include, for example, one or more microprocessors, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), and a PLD ( Includes Programmable Logic Devices), FPGAs (Field Programmable Gate Arrays), controllers, microcontrollers, electronic devices, other devices designed to perform the functions described herein, and / or combinations thereof. The embodiments shown herein are implemented, for example, by hardware, software, firmware, middleware, microcode, or a combination thereof.

The machine-readable non-temporary storage medium used herein can be further configured as a computer-readable tangible carrier (medium) composed of the categories of solid state memory, magnetic disks and optical disks. Such a medium stores an appropriate set of computer instructions such as a program module and a data structure for causing a processor to execute the technology disclosed herein. Computer-readable media include electrical connections with one or more wires, magnetic disk storage media, and other magnetic and optical storage devices (eg, CD (Compact Disk), DVD (Digital Versatile Disc), and Rewritable Blu-ray Disc, Portable Computer Disc, RAM (Random Access Memory), ROM (Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EPROM (Electrically Erasable Programmable Read-Only Memory) or Flash Memory Includes a ROM or other tangible storage medium capable of storing information in, or a combination thereof. The memory can be provided inside and / or outside the processor or processing unit. As such, the term "memory" means any kind of long-term storage, short-term storage, volatile, non-volatile or other memory, any particular type or number of memories or type of medium in which the storage is stored. Not limited.

1,1a Fuel cell device 2 Remote control 3 Current sensor 4 General load 10 Power generation unit 11 Cell stack 12, 12a Auxiliary equipment 13 Heater (1st heater)
14 heater (second heater)
15 Blower 16 Pump 17 Fan 20 Power conversion unit 30, 31 Switch 40 Communication unit 50 Storage unit 60 Control unit 100 Power system

Claims (6)

Auxiliary equipment including a heater and
A control unit that detects an abnormality in the current sensor based on a detected value flowing from the power system to the auxiliary machine, which is detected by the current sensor when the auxiliary machine is in operation.
Equipped with a,
The control unit
An abnormality of the current sensor is detected based on the detected value and a reference value detected by the current sensor when the auxiliary machine is in a non-operating state.
When it is determined that the detected value is below the threshold value, the heater in the operating state is put into the non-operating state.
The threshold value is a value obtained by adding a reference value detected by the current sensor when the heater is in a non-operating state to the rated current value of a switch located between the heater and the power system. apparatus. In the fuel cell device according to claim 1,
The control unit is a fuel cell device that detects an abnormality of the current sensor a plurality of times. In the fuel cell device according to claim 1 or 2 .
The control unit acquires a first predetermined number of inspection results of the current sensor based on the detected value and the reference value, and detects an abnormality of the current sensor based on the acquired first predetermined number of inspection results. , Fuel cell device. In the fuel cell device according to any one of claims 1 to 3 .
Based on the detected value and the reference value, the control unit determines that the current sensor is abnormal when a second predetermined number of inspection results indicating that the current sensor is abnormal are continuously obtained. Fuel cell device. In the fuel cell device according to any one of claims 1 to 4 .
When the control unit determines that the current sensor is abnormal, the fuel cell device transmits to at least one of the remote controller and the remote server that the current sensor is abnormal. It is a method to detect the abnormality of the current sensor.
Steps to operate auxiliary equipment including heaters and
It said current sensor detects when the auxiliary machine is in a working state, based on the detection value flowing from the power system to the auxiliary machine, a detection step an abnormality of the current sensor,
A step of detecting an abnormality of the current sensor based on the detected value and a reference value detected by the current sensor when the auxiliary machine is in a non-operating state.
When the detected value is determined to be below the threshold, it sees contains the steps of the heater is working state to the non-operating state, and
The threshold value is a value obtained by adding a reference value detected by the current sensor when the heater is in a non-operating state to the rated current value of a switch located between the heater and the power system. How to detect anomalies.

Images