JP4942948B2 - Fuel cell degradation determination apparatus and degradation determination method - Google Patents

Description

  The present invention relates to a fuel cell deterioration determination device and a deterioration determination method, and more particularly to a fuel cell deterioration determination device and a deterioration determination method used as a backup power source.

  Conventionally, in various devices such as communication devices, there is a backup power supply system that continuously supplies power to a DC load or an AC load even when an AC power supply such as a commercial power supply is interrupted.

A conventional backup power supply system will be described below.
First, the configuration of a conventional backup power supply system will be described with reference to FIG. FIG. 6 is a block diagram showing the configuration of a conventional backup power supply system.
The backup power supply system 100 of FIG. 6 is disposed on a current path from an AC power source 2 such as a commercial power source to a DC load 3. The backup power supply system 100 includes a rectifier 110 whose input is connected to the output of the AC power supply 2 and whose output is connected to the DC load 3. The rectifier 110 converts the output voltage (AC voltage) of the AC power supply 2 input to the input unit into a DC voltage (for example, a DC voltage having a voltage value of 50 (V)), and outputs the DC voltage from the output unit. .

  The backup power supply system 100 includes a secondary battery 120 and a fuel cell 130 that charge and discharge as a backup power supply. The secondary battery 120 is connected to a node N100 on the power line from the rectifier 110 to the DC load 3. The fuel cell 130 includes a hydrogen cylinder, and generates a DC voltage using the hydrogen filled in the hydrogen cylinder as fuel. The fuel cell 130 converts the output voltage (DC voltage) of the cell stack 131 and the cell stack 131 into a DC voltage having a different voltage value (for example, 49.5 (V)) and outputs it (DC / DC converter) 132. A battery 133, a voltage detector 134, and a controller 135. The battery 133 serves as a power source for the fuel cell 130 in the event of a power failure of the AC power source 2, and is connected to the output of the rectifier 110 and is recovered and charged by the output voltage (DC voltage) of the rectifier 110, although not shown. The The voltage detector 134 is used to detect the input voltage (load voltage) input to the DC load 3, and the controller 135 starts the fuel cell 130 based on the input voltage (load voltage) input to the DC load 3, Or stop.

  Next, the operation of the backup power supply system 100 having the configuration shown in FIG. 6 will be described with reference to FIG. FIG. 7 is a waveform diagram for explaining the operation of the backup power supply system 100 of FIG. In FIG. 7, the horizontal axis represents time, and the vertical axis represents the voltage value (voltage value of the load voltage) (V) of the voltage input to the DC load 3. In the description of the operation, it is assumed that a power failure occurs in the AC power supply 2 and then the power is restored. However, the operation is substantially the same for the failure of the AC power supply 2 and the failure of the rectifier 110 in general.

  At time T101 when the AC power supply 2 and the rectifier 110 are normal, the output voltage of the AC power supply 2 is input to the input section of the rectifier 110, the AC voltage is converted into a DC voltage by the rectifier 110, and the DC voltage is output from the output section. The The DC voltage output from the rectifier 110 is supplied to the DC load 3. At this time, the DC voltage output from the output part of the rectifier 110 is supplied to each of the secondary battery 120 and the battery 133 of the fuel cell 130, and these are float-charged. At this time, the voltage detector 134 of the fuel cell 130 detects the voltage value of the input voltage (load voltage) input to the DC load 3.

When a power failure occurs in the AC power source 2 at time T102, the supply of the DC voltage from the rectifier 110 to the DC load 3 is stopped, but the secondary battery 120 is instantaneously discharged and the discharge voltage (DC voltage) of the secondary battery 120 is discharged. ) Is supplied to the DC load 3.
After that, at time T103, the discharge voltage (DC voltage) of the secondary battery 120 is supplied to the DC load 3. At this time T103, the voltage value of the load voltage supplied to the DC load 3 decreases with the passage of time, that is, with the discharge of the secondary battery 120. At this time, the voltage detector 134 of the fuel cell 130 detects the voltage value of the input voltage (load voltage) input to the DC load 3.

  At time T104, the voltage detector 134 of the fuel cell 130 determines that the voltage value of the load voltage is a predetermined first reference voltage value (lower than the voltage value of the DC voltage output from the rectifier 110 at normal time, for example 48 (V )) When it is detected that the value is less than, a start signal for instructing the controller 135 to start the fuel cell 130 is output. The controller 135 receives the activation signal from the voltage detector 134 and activates the fuel cell.

  At time T105 after the fuel cell 130 is activated and the output of the fuel cell 130 is established, the fuel cell 130 outputs a DC voltage from the converter 132, and this DC voltage is supplied to the DC load 3 via the diode 140. . At this time, the voltage detector 134 of the fuel cell 130 detects the voltage value of the input voltage (load voltage) input to the DC load 3.

When the AC power supply 2 is restored at time T106, the output voltage (AC voltage) of the AC power supply 2 is input to the input unit of the rectifier 110 at time T106 and the subsequent time T107, and the AC voltage is converted into a DC voltage by the rectifier 110. And a DC voltage is output from the output section of the rectifier 110. The DC voltage output from the rectifier 110 is supplied to the DC load 3. At this time, the DC voltage output from the output part of the rectifier 110 is supplied to each of the secondary battery 120 and the battery 133 of the fuel cell 130, and these are float-charged.
At time T108 after the AC power supply 2 is restored, the voltage detector 134 of the fuel cell 130 has a second reference voltage value (the output voltage at the time when the output of the fuel cell 130 is established). When it is detected that the voltage value is exceeded, for example, 49.5 (V)), a stop signal for instructing the controller 135 to stop the fuel cell 130 is output. The controller 135 receives the stop signal from the voltage detector 134 and stops the fuel cell.
Conventionally, there is a backup power supply system that includes a fuel cell as a backup power source and supplies power to the DC load or the AC load from the fuel cell when the AC power supply fails (for example, Patent Document 1 and Patent Document 2). reference.).
JP 2000-341881 A JP 2000-341879 A

  Hereinafter, an IV characteristic which is a relationship between the output current of the cell stack 131 and the output voltage of the cell stack 131 of the fuel cell 130 will be described with reference to FIG. FIG. 8 is a diagram showing an outline of the IV characteristic of the fuel cell. In FIG. 8, the horizontal axis represents the cell stack output current (cell stack output current) (A), and the vertical axis represents the cell stack output voltage (cell stack output voltage) (V). The initial IV characteristics refer to, for example, the IV characteristics at the time of inspection before shipping the fuel cell.

As shown in FIG. 8, the IV characteristic of the fuel cell 130 deteriorates with time. When the I-V characteristic of the fuel cell 130 is degraded, even with the same cell stack output current I _a, the cell stack output voltage decreases. In other words, the output power of the fuel cell 130 is lower than the initial output power. For this reason, when a power failure of the AC power supply 2 or a failure of the rectifier 110 occurs, if the deterioration of the IV characteristics of the fuel cell 130 proceeds, the DC power necessary for the DC load 3 is supplied from the fuel cell 130. The case where it cannot supply will arise. That is, the fuel cell 130 does not fulfill the purpose of backing up the AC power supply 2.

In order to reliably achieve the purpose of the fuel cell 130 performing the backup of the AC power supply 2, the fuel cell 130 has to be supplied before the necessary DC power can be supplied to the DC load 3 due to the deterioration of the IV characteristics of the fuel cell 130. The battery 130 needs to be replaced.
For this reason, it is desirable to determine the deterioration of the IV characteristics of the fuel cell. However, until now, a fuel cell has rarely been used as a backup power source for a backup power supply system, and a deterioration determination device and a deterioration determination method for a fuel cell have not been developed.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel cell deterioration determination device and a deterioration determination method capable of determining the deterioration of a fuel cell.

The fuel cell degradation determination device of the present invention comprises a switching means for switching the output destination of the output power of the cell stack constituting the fuel cell from a load to an external load when determining the degradation of the fuel cell, and the output power of the cell stack A backup power source having first external output means for outputting to an external load, and second external output means for outputting the output current and output voltage of the cell stack, when no power is supplied from the power source Data storage means for associating and storing the reference output power of the cell stack as a reference for the output current of the cell stack and the type for each type of fuel cell that supplies power to the load as The output current and output voltage of the cell stack connected to the external output means and output from the second external output means are used to determine the deterioration of the fuel cell. Detection means for detecting the, is connected to the first external output means, and discharge means as the external load that consumes all of the output power of the fuel cell when the deterioration determination of the fuel cell, detected by said detecting means A reference output power extraction unit that extracts a reference output power for the output current of the cell stack that has been generated from the data storage unit, and an output current of the cell stack and an output voltage of the cell stack detected by the detection unit The determination output power calculation means for determining the determination output power of the cell stack at the time of deterioration determination, and the determination output power calculation means for the reference output power extracted by the reference output power extraction means A ratio calculating means for calculating the ratio of the output power at the time of determination, and outputting the ratio calculated by the ratio calculating means Characterized by comprising a ratio output means that the

In the fuel cell deterioration determination device, when power is supplied from the power source , the secondary battery is charged with power supplied from the power source, and when power is not supplied from the power source, Electric power is supplied to the load from the secondary battery and the cell stack constituting the fuel cell.
In the fuel cell deterioration determination apparatus, the ratio output by the ratio output means is a display.

The method for determining deterioration of a fuel cell according to the present invention comprises a switching means for switching an output destination of output power of a cell stack constituting a fuel cell from a load to an external load when determining deterioration of the fuel cell, and the output power of the cell stack is The first external output means for outputting to an external load and the second external output means for outputting the output current and output voltage of the cell stack, and the backup power supply when power is not supplied When determining the deterioration of the fuel cell that supplies power to the load, the detection means connected to the second external output means outputs the output current and output voltage of the cell stack output from the second external output means. The detection procedure to be detected and the discharge means connected to the first external output means all output power of the fuel cell at the time of judging the deterioration of the fuel cell. In the detection procedure from the data storage means for storing the discharge procedure for consuming the battery cell, the reference output power of the cell stack as a reference for the output current of the cell stack, and the type for each type of the fuel cell Degradation determination using a reference output power extraction procedure for extracting a reference output power with respect to the detected output current of the cell stack, and an output current of the cell stack and an output voltage of the cell stack detected by the detection procedure Output power calculation procedure at the time of determination to determine the output power at the time of determination of the cell stack at the time, and output at the time of determination obtained in the output power calculation procedure at the time of determination with respect to the reference output power extracted in the reference output power extraction procedure The ratio calculation procedure for calculating the ratio of power and the ratio calculated in the ratio calculation procedure are output. And having a ratio output procedure for, the.

  According to the present invention, the reference output power of the cell stack as a reference for the output current of the cell stack constituting the fuel cell is stored in the data storage means. When determining the deterioration of the fuel cell, the output current and the output voltage of the cell stack constituting the fuel cell are detected, and the output power of the cell stack at the time of determining the deterioration (determination output power) is calculated. Using the reference output power stored in the data storage means and the calculated determination output power, the ratio of the determination output power to the reference output power of the fuel cell is calculated, and the calculated ratio is output. By doing so, it is possible to realize a fuel cell deterioration determination device and a deterioration determination method for determining deterioration of a fuel cell.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
Before describing the configuration and operation of the fuel cell deterioration determination apparatus in the embodiment of the present invention, first, referring to FIGS. 1 and 2 for data used for determination of deterioration of a fuel cell and data prepared in advance. I will explain.

  FIG. 1 is a graph showing the IV characteristics of a fuel cell and the relationship between the output current of the cell stack and the output power of the cell stack (hereinafter referred to as the IP characteristic). In FIG. 1, the horizontal axis represents the cell stack output current (cell stack output current) (A), the vertical axis represents the cell stack output voltage (cell stack output voltage) (V), and the cell stack output power (cell stack output power). ) (W).

In FIG. 1, IV characteristics _{IV 100} indicates the initial IV characteristic of the fuel cell, it referred to the cell stack output voltage of the cell stack output current _{I n} and _{V 100n.} Also, IP characteristics _{IP 100} indicates the initial IP properties of the fuel cell, the cell stack output power in the cell stack output current _{I n} referred to as _{P 100n.}
IV characteristics _{IV 95n} is 5 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel cell of IV characteristics when lowered, the cell the cell stack output voltage in the stack output current _{I n} referred to as _{V 95n.} Also, IP characteristics _{IP 95n} is 5 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel IP properties of the battery when the reduction , the cell stack output power in the cell stack output current _{I n} referred to as _{P 95n.}

IV characteristics _{IV 90n} is 10 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel cell of IV characteristics when lowered, the cell the cell stack output voltage in the stack output current _{I n} referred to as _{V 90n.} Also, IP characteristics _{IP 90n} is 10 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel IP properties of the battery when the reduction , the cell stack output power in the cell stack output current _{I n} referred to as _{P 90n.}
IV characteristics _{IV 85n} is 15 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel cell of IV characteristics when lowered, the cell the cell stack output voltage in the stack output current _{I n} referred to as _{V 85n.} Also, IP characteristics _{IP 85n} is 15 (%) cell stack output voltage relative to the initial cell stack output voltage _{V 100n} in the cell stack output current _{I n} indicates the fuel IP properties of the battery when the reduction , the cell stack output power in the cell stack output current _{I n} referred to as _{P 85n.}

As the fuel cell over time, IV characteristics of the fuel cell is degraded IV characteristics _IV 100, IV characteristics _IV 95n, IV characteristics _IV 90n, and IV characteristics _{IV 85n.} Further, as can be seen from FIG. 1, the cell stack output voltage decreases even with the same cell stack current.

FIG. 2 shows the relationship between the cell stack output voltage drop value (hereinafter referred to as cell stack output voltage difference) ΔV and the cell stack output power at the cell stack output voltage (hereinafter referred to as “cell stack output voltage”). It is a figure showing ΔV-P relation. In FIG. 2, the horizontal axis represents the cell stack output voltage difference (V), and the vertical axis represents the cell stack output power (W). Incidentally, .DELTA.VP relationship .DELTA.VP _n in FIG. 2 is a .DELTA.VP relationship in the cell stack output current _{I n} of FIG.

In .DELTA.VP relationship .DELTA.VP _n in the cell stack output current _{I n} of FIG. 2, the cell stack output power corresponding cell stack output voltage difference ΔV is the 0 (V) is the initial cell stack output power _{P 100n.} Cell stack output power P when the cell stack output voltage difference _{ΔV 100n-95n (= V 100n} -V 95n) to the cell stack output voltage of the cell stack output power corresponding cell stack output current _{I n} the 5 (%) was reduced _95n . Cell stack output power P when the cell stack output power corresponding to the cell stack output voltage difference _{ΔV 100n-90n (= V 100n} -V 90n) is the cell stack output voltage of the cell stack output current _{I n} has dropped 10% _90n . Cell stack output power P when the cell stack output power corresponding to the cell stack output voltage difference _{ΔV 100n-85n (= V 100n} -V 85n) is the cell stack output voltage of the cell stack output current _{I n} has dropped 15% _85n .
The ΔV-P relationship shown in FIG. 2 is prepared in advance for each fuel cell product, for example, at intervals of 0.1 (A) of the cell stack output current. Then, the above-described ΔV-P relationship will be described later of the deterioration determination apparatus 1 in FIG. 3 in association with information indicating the product of the fuel cell (for example, B type 1 kW manufactured by Company A) and the current value of the cell stack output current. Store in the data storage unit 12.

Hereinafter, the configuration of the fuel cell deterioration determination apparatus according to the embodiment of the present invention will be described with reference to FIG. FIG. 3 is a block diagram showing the configuration of the deterioration determination apparatus in the present embodiment. However, FIG. 3 is a diagram illustrating a configuration when the deterioration determination apparatus is applied to the backup power supply system 100 whose configuration and operation are described with reference to FIGS. 6 and 7. Since the configuration and operation of the backup power supply system 100 to which the fuel cell degradation determination apparatus 1 of FIG. 3 is applied have been described with reference to FIGS. 6 and 7, the description of the configuration and operation of the backup power supply system 100 is omitted.
3 can be used for determining the deterioration of a fuel cell provided as a backup power source in various backup power supply systems, and for determining the deterioration of a fuel cell used for other than the backup power source. Is also available.

The degradation determination apparatus 1 shown in FIG. 3 has a power supply unit 11 that receives an output of an AC power supply 2 such as a commercial power supply and supplies power necessary for operation to each unit of the degradation determination apparatus 1.
The degradation determination device 1 includes a data storage unit 12, and the data storage unit 12 correlates with the information indicating the fuel cell product and the current value of the cell stack output current (see FIG. 2). ) Is stored. However, the ΔV-P relationship is stored in the data storage unit 12 for each fuel cell product in every 0.1 (A) of the cell stack output current in this embodiment.

The deterioration determination device 1 has a setting unit 13. The setting unit 13 outputs information indicating the product of the fuel cell subject to deterioration determination, which is input from the input unit (not shown) using the input unit (not shown) to the calculation unit 16.
The degradation determination device 1 includes a discharge unit 14 made of a resistance element, and the discharge unit 14 is connected to the output of the converter 132 of the fuel cell 130 through an output line line1. The discharge unit 14 is a load when determining the deterioration of the fuel cell 130 and consumes the output power of the fuel cell 130. Thus, by providing the discharge unit 14 in the deterioration determination device 1, the output of the fuel cell 130 at the time of deterioration determination of the fuel cell 130 can be consumed in the deterioration determination device 1 with the discharge unit 14 as a load. Therefore, it is possible to prevent the output of the fuel cell 130 when determining the deterioration of the fuel cell 130 from affecting the current DC load 3.

  The degradation determination device 1 includes a detection unit 15, and the detection unit 15 is connected to the cell stack 131 of the fuel cell 130 by a detection line line 2. The detection unit 15 detects the cell stack output voltage and the cell stack output current output from the cell stack 131 of the fuel cell 130. The detection unit 15 outputs the detected cell stack output voltage and cell stack output current to the calculation unit 16.

The degradation determination device 1 includes a calculation unit (reference output power extraction means, determination output power calculation means, ratio calculation means) 16 constituted by a CPU (Central Processing Unit). The calculation unit 16 uses the information indicating the deterioration determination target fuel cell product input from the setting unit 13 and the cell stack output current input from the detection unit 15, and associates them with the data storage unit. 12 is extracted (see FIG. 2). However, when the ΔV-P relationship is extracted from the data storage unit 12, since the ΔV-P relationship is stored every 0.1 (A), the cell stack output current is set to 0.1 (A) units. And the ΔV-P relationship is extracted.
In the extracted ΔV-P relationship, the arithmetic unit 16 outputs the cell stack output power in which the cell stack output voltage difference ΔV is 0 (V) (the initial cell stack of the fuel cell at the cell stack output current detected by the detection unit 15). Output power) is extracted. In the present embodiment, the reference output power of the cell stack is based on the cell stack output power at which the cell stack output voltage difference ΔV is 0 (V).

The calculation unit 16 calculates cell stack output power (= cell stack output current × cell stack output voltage) using the cell stack output current and the cell stack output voltage input from the detection unit 15. The calculated cell stack output power is the cell stack output power at the time of determining the deterioration of the fuel cell in the cell stack output current detected by the detection unit 15.
The computing unit 16 calculates a ratio of the calculated cell stack output power at the time of deterioration determination to the extracted initial cell stack output power (= cell stack output power at the time of deterioration determination / initial cell stack output power × 100), The calculation result is output to the display unit 17.

The display unit 17 is composed of a liquid crystal display or the like, and a display example thereof is shown in FIG. FIG. 4 is a diagram showing a display example of the display unit 17. In the display example shown in FIG. 4, the horizontal axis represents the ratio (%) of the cell stack output power at the time of deterioration determination with respect to the initial cell stack output power.
The display unit 17 displays an arrow 17a at a position corresponding to the ratio of the cell stack output power at the time of deterioration determination with respect to the initial cell stack output power input from the calculation unit 16. As a result, the operator can grasp the degree of deterioration of the fuel cell and can easily determine whether or not the fuel cell needs to be replaced.

In the display example, the state of the fuel cell is divided into three stages, and the display color of the display screen is changed for each division.
Specifically, in the green display area 17G of the display screen, the ratio (%) of the cell stack output power at the time of deterioration determination with respect to the initial cell stack output power is 87.5 (%) or more. In the present embodiment, it is assumed that this region is in a state of a fuel cell that can output sufficient power as a backup power source.
In the yellow display area 17Y of the display screen, the ratio (%) of the cell stack output power at the time of deterioration determination with respect to the initial cell stack output power is 72.5 (%) or more and less than 87.5 (%). In this embodiment, this region is in the state of the fuel cell in which the fuel cell can output the power necessary as a backup power source, but the deterioration of the fuel cell is progressing and it is desirable to replace the fuel cell. And
In the red display area 17R of the display screen, the ratio (%) of the cell stack output power at the time of deterioration determination with respect to the initial cell stack output power is less than 72.5 (%). In the present embodiment, it is assumed that this region is in the state of the fuel cell because the fuel cell cannot output the power required as a backup power source and it is desirable to immediately replace the fuel cell.

  Thus, by dividing the display area and changing the display color according to the state of the fuel cell described above, the operator can more easily grasp the degree of deterioration of the fuel cell, and the necessity of replacing the fuel cell can be confirmed. Furthermore, it becomes possible to grasp easily.

Next, the fuel cell deterioration determination operation performed by the deterioration determination apparatus 1 having the configuration shown in FIG. 3 will be described with reference to FIG. FIG. 5 is a flowchart showing an operation procedure of the fuel cell deterioration determination performed by the deterioration determination apparatus 1 of FIG.
First, the operator inputs information indicating the product of the fuel cell subject to deterioration determination using an input unit (not shown). The input unit outputs information indicating the product of the fuel cell input to the setting unit 13, and the setting unit 13 receives the information indicating the product of the fuel cell targeted for deterioration determination input from the input unit to the calculation unit 16. Output (step S101). In addition to setting information indicating the product of the fuel cell subject to deterioration determination in the deterioration determination device 1, the operator uses the output capacity setting key (not shown) provided in the fuel cell 130 to set the output capacity of the fuel cell 130. Set. Further, when the AC power supply 2 and the rectifier 110 are operating normally, power is supplied to the DC load 3 by the rectifier 110, and the fuel cell 130 is on standby in preparation for a power failure of the AC power supply 2 or a failure of the rectifier 110. Is in a state of being. For this reason, the operator further presses a start button (not shown) provided in the fuel cell 130. The fuel cell 130 is activated when the activation button is pressed, and starts supplying power with the set output capacity.

The output power of the converter 132 of the fuel cell 130 is supplied to the discharge unit 14 via the output line line 1, and the output power of the converter 132 of the fuel cell 130 is consumed by the discharge unit 14. In this way, since the output power of the fuel cell 130 is consumed by the discharge unit 14, the output power of the fuel cell 130 does not affect the current DC load 3.
At this time, the detection unit 15 detects the cell stack output current and the cell stack output voltage of the cell stack 131 of the fuel cell 130, and outputs the detected cell stack output current and the cell stack output voltage to the calculation unit 16 ( Step S102).

  The calculation unit 16 uses the information indicating the deterioration determination target fuel cell product input from the setting unit 13 and the cell stack output current input from the detection unit 15, and associates them with the data storage unit. 12 is extracted (see FIG. 2). Then, in the extracted ΔV-P relationship, the calculation unit 16 outputs the cell stack output power with the cell stack output voltage difference ΔV being 0 (V) (the initial value of the fuel cell in the cell stack output current detected by the detection unit 15). Cell stack output power) is extracted (step S103).

  The calculation unit 16 calculates cell stack output power (= cell stack output current × cell stack output voltage) at the time of deterioration determination using the cell stack output current and the cell stack output voltage input from the detection unit 15. (Step S104).

  The calculation unit 16 calculates the ratio of the cell stack output power at the time of deterioration determination calculated at step S104 to the reference cell stack output power extracted at step S103 (= cell stack output power at the time of deterioration determination / initial cell stack output). (Power x 100) is calculated, and the calculation result is output to the display unit 17 (step S105).

  The display unit (ratio output means) 17 displays an arrow 17a at a position corresponding to the ratio (%) of the cell stack output power at the time of deterioration determination with respect to the reference cell stack output power input from the calculation unit 16 (step S106). ). The operator looks at the display unit 17 and grasps the degree of progress of deterioration of the fuel cell 130 subject to deterioration determination. After grasping, the worker presses a stop button (not shown) provided in the fuel cell 130. The fuel cell 130 stops when the stop button is pressed.

According to the deterioration determination device of the present embodiment described above, the reference cell stack output power of the fuel cell with respect to the cell stack output current is stored in the data storage unit 12, and the cell stack 131 of the fuel cell 130 at the time of deterioration determination is stored. The cell stack output current and the cell stack output voltage are detected. The reference cell stack output power with respect to the cell stack output current detected at the time of deterioration determination is taken out from the data storage unit 12, and the cell stack output power of the fuel cell at the time of deterioration determination is calculated from the detected cell stack output current and cell stack output voltage. calculate. Then, the ratio of the cell stack output power at the time of deterioration determination with respect to the extracted reference cell stack output power is calculated, and the calculated ratio is displayed. By doing so, it is possible to realize a fuel cell deterioration determination device and a deterioration determination method for determining deterioration of a fuel cell. Further, the deterioration determination operator can easily grasp the progress of deterioration of the fuel cell from the displayed ratio.
Moreover, since the discharge unit 14 that consumes the output power of the fuel cell 130 at the time of deterioration determination is provided in the deterioration determination device 1, the output power of the fuel cell 130 at the time of deterioration determination affects the current DC load 3. Can be prevented.

The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims.
For example, in the above-described embodiment, the initial output power of the cell stack is set as the reference output power of the cell stack, and the ratio of the output power of the cell stack at the time of deterioration determination is calculated. However, it is not limited to this. For example, the cell stack output power that needs to be replaced due to the progress of deterioration of the fuel cell is used as the reference output power of the cell stack, and the ratio of the output power of the cell stack at the time of deterioration determination relative to this is calculated. Good. In this case, if the ratio is 100% or more, the fuel cell can supply power necessary for the load, and if the ratio is less than 100%, the fuel cell supplies power necessary for the load. I can't.

The figure which shows the IV characteristic of a fuel cell, and the relationship between the output current of a cell stack, and the output power of a cell stack. The figure which shows the relationship between the cell stack output voltage difference in which the cell stack output voltage of the fuel cell decreased, and the cell stack output power. The block diagram which shows the structure of the deterioration determination apparatus in embodiment of this invention. The figure which shows the example of a display of the display part of FIG. The flowchart which shows the operation | movement procedure of the fuel cell degradation determination which the degradation determination apparatus of FIG. The block diagram which shows the structure of the conventional backup power supply system. FIG. 7 is a waveform diagram for explaining the operation of the backup power supply system of FIG. 6. The figure which shows the outline of the IV characteristic of a fuel cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Degradation determination apparatus 11 Power supply part 12 Data storage part 13 Setting part 14 Discharge part 15 Detection part 16 Calculation part 17 Display part 130 Fuel cell 131 Cell stack

Claims (4)

Switching means for switching the output destination of the output power of the cell stack constituting the fuel cell from a load to an external load when determining deterioration of the fuel cell, and a first external output means for outputting the output power of the cell stack to the external load If has a second external output means for outputting an output current and an output voltage of the cell stack, the fuel cell supplies power to the load as a backup power source when the power from the power source is not supplied For each type, data storage means for storing the cell stack reference output power as a reference for the cell stack output current and the type in association with each other ,
Detecting means connected to the second external output means for detecting an output current and an output voltage of the cell stack output from the second external output means at the time of determining the deterioration of the fuel cell ;
Discharging means as the external load that is connected to the first external output means and consumes all of the output power of the fuel cell at the time of determining the deterioration of the fuel cell;
Reference output power extraction means for extracting, from the data storage means, reference output power for the output current of the cell stack detected by the detection means;
A determination time output power calculation means for obtaining a determination time output power of the cell stack at the time of deterioration determination using the output current of the cell stack and the output voltage of the cell stack detected by the detection means;
A ratio calculating means for calculating a ratio of the determination output power calculated by the determination output power calculation means with respect to the reference output power extracted by the reference output power extraction means;
A ratio output means for outputting the ratio calculated by the ratio calculation means;
A fuel cell deterioration determination device comprising: When power is supplied from the power source, the secondary battery is charged with the power supplied from the power source. When power is not supplied from the power source, the secondary battery and the fuel cell are connected. The fuel cell deterioration determination device according to claim 1, wherein electric power is supplied to the load from the cell stack constituting the fuel cell stack.   3. The fuel cell deterioration determination apparatus according to claim 1, wherein the ratio output by the ratio output means is a display. Switching means for switching the output destination of the output power of the cell stack constituting the fuel cell from a load to an external load when determining deterioration of the fuel cell, and a first external output means for outputting the output power of the cell stack to the external load If has a second external output means for outputting an output current and an output voltage of the cell stack, the deterioration determination of the fuel cell for supplying power to the load as a backup power source when the power is not supplied A detection procedure for detecting an output current and an output voltage of the cell stack output from the second external output means by a detection means connected to the second external output means ,
A discharge procedure for consuming all of the output power of the fuel cell by the discharge means connected to the first external output means when determining the deterioration of the fuel cell;
For each type of the fuel cell, the reference output power of the cell stack as a reference with respect to the output current of the cell stack and the type of the cell stack detected in the detection procedure from the data storage means that stores the type in association with each other. A reference output power extraction procedure for extracting a reference output power for an output current;
A determination-time output power calculation procedure for obtaining a determination-time output power of the cell stack at the time of deterioration determination using the output current of the cell stack and the output voltage of the cell stack detected by the detection procedure;
A ratio calculation procedure for calculating a ratio of the determination output power obtained in the determination output power calculation procedure with respect to the reference output power extracted in the reference output power extraction procedure;
A ratio output procedure for outputting the ratio calculated in the ratio calculation procedure;
A method for determining deterioration of a fuel cell, comprising:

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