Electrochemical module diagnostic system, diagnostic method, and diagnostic program

Abstract

Provided in an embodiment is a diagnosis device for an electrochemical module in which at least one of an anode and a cathode is equipped with a catalyst. The diagnosis device comprises an output circuit and a processor. The processor supplies inspection power from an output circuit to the electrochemical module, in a state where operation power is being input to the electrochemical module or being output from the electrochemical module, so that the inspection power is superimposed on the operation power, and in the state where the inspection power is superimposed on the operation power, a current and a voltage for the electrochemical module is measured so as to measure measurement data for diagnosis.

Description

[Technical Field]

[0001] An embodiment of the present invention is an electrochemical module diagnosis The present invention relates to a diagnostic system, a diagnostic method, and a diagnostic program. [Background technology]

[0002] Electrochemical modules are used that receive operating power, causing an electrochemical reaction, or that output operating power generated by the electrochemical reaction. In electrochemical modules that receive operating power, the input of operating power causes an electrochemical reaction, such as the electrolysis of water, and products of the electrochemical reaction, such as hydrogen, are recovered. In electrochemical modules that output operating power, fuel, such as hydrogen, and oxygen are supplied, causing an electrochemical reaction to generate operating power, which is then supplied.

[0003] Electrochemical modules operated as described above are required to be appropriately inspected by diagnosing their state of deterioration, etc. Furthermore, it is required to inspect the electrochemical modules without stopping their operation, i.e., while the operation of the electrochemical modules continues. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2022-45497 [Patent Document 2] Japanese Patent Application Publication No. 2014-154437 [Patent Document 3] Japanese Patent Application Publication No. 2017-106889 Summary of the Invention [Problem to be solved by the invention]

[0005] The problem to be solved by the present invention is to provide an electrochemical module that can be properly inspected without stopping the operation of the electrochemical module. diagnosis The present invention provides a diagnostic system, a diagnostic method, and a diagnostic program. [Means for solving the problem]

[0006] In an embodiment, The diagnostic system includes an electrochemical module, an output circuit, a power conditioner, and a processor. The electrochemical module includes an anode and a cathode; At least one of the anode and the cathode is provided with a catalyst. In the electrochemistry module, An electrochemical reaction occurs when operating power is input, or an operating power generated by the electrochemical reaction is output. do. The output circuit is , AC power whose current value changes periodically, Inspection Power as It can be output. The power regulator adjusts the operating power input to or output from the electrochemical module, and also adjusts the operating power so that the current value in the electrochemical module falls within a standard fluctuation range centered on a target current value. When operating power is being input to or output from the electrochemical module, the processor causes the electrochemical module to supply test power from the output circuit, thereby superimposing the test power on the operating power, and when the test power is being superimposed on the operating power, measures the current and voltage of the electrochemical module to measure diagnostic measurement data. The processor sets the reference fluctuation range to be larger than the fluctuation range of the current value of the AC power that is the inspection power, while the inspection power is superimposed on the operating power. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram schematically illustrating an example of a diagnostic system according to an embodiment. [Figure 2] FIG. 2 is a flowchart showing an example of processing performed by a processing circuit and the like of the diagnostic device when measuring diagnostic measurement data for each of a plurality of electrochemical modules in the diagnostic system according to the embodiment. [Figure 3] FIG. 3 is a flowchart illustrating an example of a process for measuring diagnostic measurement data for the measurement target module shown in FIG. [Figure 4] FIG. 4 is a schematic diagram illustrating the process of changing the reference fluctuation range for the current value in the measurement target module shown in S112 of FIG. [Figure 5] FIG. 5 is a flowchart showing an example of processing performed by the processing circuit of the diagnostic device according to the embodiment in analyzing diagnostic measurement data for one electrochemical module. [Figure 6] FIG. 6 is a flowchart that schematically illustrates an example of a process for controlling the power input to one electrochemical module, which is performed by the processing circuit of the diagnostic device according to the embodiment when no diagnosis is being performed. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described with reference to the drawings.

[0009] FIG. 1 shows an example of a diagnostic system 1 according to an embodiment. The diagnostic system 1 includes one or more electrochemical modules 2. In the example shown in FIG. 1, the diagnostic system 1 is provided with a plurality of electrochemical modules 2. Each of the electrochemical modules 2 can be connected to a power grid 3, and operating power, which is the power used for operation, is input to each of the electrochemical modules 2 through the power grid 3. Examples of the power grid 3 include a power grid that supplies power from a generator that generates power using natural energy such as solar power and wind power, and a power grid that supplies power from a power plant. In one example, power from a generator that generates power using natural energy is supplied to the diagnostic system 1 through the power grid 3, thereby inputting operating power to each of the electrochemical modules 2. In the example shown in FIG. 1, operating power can be input to the plurality of electrochemical modules 2 independently of each other, and the plurality of electrochemical modules 2 can be connected to the power grid 3 independently of each other.

[0010] Each of the plurality of electrochemical modules 2 includes one or more electrochemical cells (not shown). When each of the electrochemical modules 2 includes a plurality of electrochemical cells, the plurality of electrochemical cells are electrically connected to each other in each of the electrochemical modules 2. In this case, in each of the electrochemical modules 2, the plurality of electrochemical cells may be electrically connected in series, or the plurality of electrochemical cells may be electrically connected in parallel. Furthermore, each of the electrochemical modules 2 may have both a structure in which the plurality of electrochemical cells are electrically connected in series and a structure in which the plurality of electrochemical cells are electrically connected in parallel.

[0011] In each of the electrochemical modules 2, one or more electrochemical cells each include an anode and a cathode, and at least one of the anode and the cathode includes a catalyst. In this embodiment, DC power is input to each of the electrochemical modules 2 as operating power. Then, in each of the electrochemical modules 2, electrochemical reactions occur in the electrochemical cells due to the input of operating power. Then, products generated by the electrochemical reactions in each of the electrochemical modules 2 are collected.

[0012] In one example, each of the electrochemical modules 2 includes one or more water electrolysis cells as electrochemical cells. Water is supplied to each of the electrochemical modules 2. In this case, operating power is input to each of the electrochemical modules 2 serving as a water electrolysis module, and hydrogen ions and oxygen are generated at the anodes of the electrochemical cells. Operating power is input to each of the electrochemical modules 2, and hydrogen ions generated at the anodes of the electrochemical cells move to the cathodes of the electrochemical cells, and hydrogen is generated at the cathodes. In this example, as described above, operating power is input to each of the electrochemical modules 2, and electrolysis of water occurs as an electrochemical reaction. Hydrogen, which is a product of the electrolysis of water, is then collected.

[0013] In one example, each of the electrochemical modules 2 includes one or more P2C (power to chemicals) cells as electrochemical cells. In each of the electrochemical modules 2, water is supplied to the anode of each of the P2C cells, and carbon dioxide is supplied to the cathode of each of the P2C cells. In each of the electrochemical modules 2, operating power is input, and oxygen is produced from water at the anode of each of the electrochemical cells, and carbon monoxide is produced from carbon dioxide at the cathode of each of the electrochemical cells. In this example, as described above, operating power is input to each of the electrochemical modules 2, and electrolysis of water and carbon dioxide occurs as an electrochemical reaction. Then, oxygen, which is a product of the electrolysis of water, and carbon monoxide, which is a product of the electrolysis of carbon dioxide, are recovered.

[0014] The diagnostic system 1 is provided with the same number of measurement circuits 5 as the number of electrochemical modules 2, one measurement circuit 5 for each electrochemical module 2. Each measurement circuit 5 measures the current and voltage for a corresponding one of the electrochemical modules 2. For example, each measurement circuit 5 measures the current input to a corresponding one of the electrochemical modules 2 and the voltage applied to the entire electrochemical module 2. Each measurement circuit 5 may also measure the temperature of a corresponding one of the electrochemical modules 2. Therefore, each measurement circuit 5 may include an ammeter that measures the current and a voltmeter that measures the voltage, as well as a temperature sensor that measures the temperature.

[0015] Furthermore, when a plurality of electrochemical cells are provided in each of the electrochemical modules 2, each of the measurement circuits 5 may measure any one of the current, voltage, and temperature of each of the plurality of electrochemical cells for each of the corresponding electrochemical modules 2. In one example, in each of the electrochemical modules 2, the plurality of electrochemical cells are electrically connected in series. Each of the measurement circuits 5 measures the current input to each of the corresponding electrochemical modules 2, and measures the voltage of each of the plurality of electrochemical cells for each of the corresponding electrochemical modules 2. In another example, in each of the electrochemical modules 2, the plurality of electrochemical cells are electrically connected in parallel. Each of the measurement circuits 5 measures the voltage applied to the entire corresponding one of the electrochemical modules 2, and measures the current of each of the plurality of electrochemical cells for each of the corresponding electrochemical modules 2.

[0016] The diagnostic system 1 is also provided with PCSs (power conditioning subsystems) 6 as power regulators, the same number as the electrochemical modules 2, one PCS 6 for each electrochemical module 2. Each PCS 6 converts power from the power grid 3 and inputs it to a corresponding one of the electrochemical modules 2. In this case, each PCS 6 converts AC power from the power grid 3 into DC power within a voltage range compatible with the electrochemical module 2, for example, by AC / DC conversion and voltage transformation, and inputs the converted DC power to a corresponding one of the electrochemical modules 2 as operating power.

[0017] Furthermore, each of the PCSs 6 adjusts the operating power input to a corresponding one of the electrochemical modules 2. Each of the PCSs 6 monitors the current and voltage at the corresponding one of the electrochemical modules 2. Each of the PCSs 6 then adjusts the operating power input to the corresponding one of the electrochemical modules 2 so that the current value at the corresponding one of the electrochemical modules 2 falls within a standard fluctuation range centered on a target current value. For example, if the current value of the current input to the corresponding one of the electrochemical modules 2 fluctuates beyond the standard fluctuation range with respect to the target current value, each of the PCSs 6 adjusts the voltage applied to the corresponding one of the electrochemical modules 2, for example, to bring the current value of the current input to the corresponding one of the electrochemical modules 2 within the standard fluctuation range centered on the target current value.

[0018] The diagnostic system 1 is also provided with a distribution adjustment circuit 7. The distribution adjustment circuit 7 is provided between each of the PCSs 6 and the power system 3, and is capable of switching the electrical connection state of each of the electrochemical modules 2 with respect to the power system 3. The distribution adjustment circuit 7 is capable of switching the electrical connection state of each of the electrochemical modules 2 with respect to the power system 3. This makes it possible to input operating power to the multiple electrochemical modules 2 independently of each other. The distribution adjustment circuit 7 also adjusts the amount of power distributed to each of the electrochemical modules 2 electrically connected to the power system 3.

[0019] The diagnostic system 1 is provided with a diagnostic device 10. The diagnostic device 10 performs a diagnosis on the electrochemical modules 2 and diagnoses the state of deterioration, etc., of each of the multiple electrochemical modules 2. The diagnostic device 10 may also diagnose the state of deterioration, etc., of one or more electrochemical cells of each of the electrochemical modules 2. In one example, the diagnostic device 10 is a processing device (computer) such as a server, and includes a processing circuit 11 and a storage medium 12. The processing circuit 11 is composed of a processor or an integrated circuit, etc., and the processor, etc. constituting the processing circuit 11 includes any of a central processing unit (CPU), an application specific integrated circuit (ASIC), a microcomputer, a field programmable gate array (FPGA), a digital signal processor (DSP), etc. The processing circuit 11 may be composed of one processor, etc., or multiple processors, etc. The storage medium 12 is either a main storage device such as a memory, or an auxiliary storage device. The diagnostic device 10 may be provided with only one memory, etc., serving as the storage medium 12, or multiple memories, etc.

[0020] The processing circuit 11 performs processing by executing programs and the like stored in the storage medium 12. For example, by executing programs and the like stored in the storage medium 12, the processing circuit 11 cooperates with the PCS 6 and the distribution adjustment circuit 7 to adjust the amount of power distributed to each of the electrochemical modules 2, and to control the current value of each of the electrochemical modules 2 to fall within a reference fluctuation range centered on a target current value. The processing circuit 11 also acquires measurement results from each of the measurement circuits 5.

[0021] 1 , a data management program 15, a diagnostic program 16, and an output control program 17 are stored in the storage medium 12 as programs executed by the processing circuitry 11. The processing circuitry 11 writes data to the storage medium 12 and reads data from the storage medium 12 by executing the data management program 15. The processing circuitry 11 also executes the diagnostic program 16 to perform the process described below for diagnosing the states of the multiple electrochemical modules 2. Furthermore, when no diagnosis is being performed, the processing circuitry 11 executes the output control program 17 to control the power input to each of the electrochemical modules 2.

[0022] In one example, the diagnostic device 10 is configured from multiple processing devices (computers) such as multiple servers, and the processors of the multiple processing devices work together to perform the processing described below in diagnosing the electrochemical module 2. In another example, a part of the diagnostic device 10 is configured from a cloud server in a cloud environment. The infrastructure of the cloud environment is configured from a virtual processor such as a virtual CPU and a cloud memory. The virtual processor performs the processing described below in diagnosing the electrochemical module 2 in place of the processing circuit 11. The cloud memory has the function of storing programs, data, etc., similar to the storage medium 12.

[0023] In one example, the diagnostic system 1 may be provided with a user interface. In this case, a user of the diagnostic system 1 or the like inputs operations related to the diagnosis of the diagnostic system 1 into the user interface. For this reason, the user interface is provided with any of a button, a mouse, a touch panel, a keyboard, or the like as an operation unit through which the user or the like inputs operations. The user interface is also provided with a notification unit that notifies information related to the diagnosis of the diagnostic system 1. The notification unit notifies the information by either displaying a screen or emitting a sound. The user interface may be mounted on a processing device that constitutes the diagnostic device 10, or may be provided separately from the processing device that constitutes the diagnostic device 10.

[0024] In the example shown in FIG. 1 , the diagnostic device 10 includes a power storage device 21 that can store electricity. The power storage device 21 is, for example, either a storage battery or a capacitor. The diagnostic system 1 is also provided with a PCS 22 as a power converter. The PCS 22 converts power from the power grid 3, inputs the converted power to the power storage device 21, and charges the power storage device 21. In this case, the PCS 22 converts, for example, AC power from the power grid 3 into DC power within a voltage range compatible with the power storage device 21 by AC / DC conversion and voltage transformation, and inputs the converted DC power to the power storage device 21.

[0025] Furthermore, the PCS 22 adjusts the power input to the power storage device 21. The PCS 22 adjusts the power input to the power storage device 21, for example, so that the current value of the current input to the power storage device 21 falls within a reference fluctuation range centered around a target current value. In the diagnostic system 1, the aforementioned distribution adjustment circuit 7 is provided between the PCS 22 and the power grid 3. The distribution adjustment circuit 7 is capable of switching the electrical connection state of the power storage device 21 with respect to the power grid 3. The distribution adjustment circuit 7 is capable of inputting power from the power grid 3 to the power storage device 21 independently of the electrochemical module 2. Furthermore, when the power storage device 21 is electrically connected to the power grid 3, the distribution adjustment circuit 7 adjusts the amount of power distributed to the power storage device 21.

[0026] The diagnostic device 10 includes an output circuit 23 and a connection switching circuit 25. The output circuit 23 is capable of outputting power such as test power to each of the electrochemical modules 2. The connection switching circuit 25 is capable of switching the electrical connection state of each of the electrochemical modules 2 with respect to the output circuit 23. The processing circuit 11 controls the operation of the output circuit 23 and the connection switching circuit 25. By controlling the operation of the output circuit 23 and the connection switching circuit 25, the output state of power from the output circuit 23 to each of the electrochemical modules 2 is controlled.

[0027] The output circuit 23 is supplied with DC power discharged from the power storage device 21. The output circuit 23 can convert the DC power into test power and output the converted test power to each of the electrochemical modules 2. The output circuit 23 outputs, for example, AC power whose current value changes periodically as the test power. In this case, any of a sine wave, a triangular wave, a sawtooth wave, and an M-sequence signal is output from the output circuit 23 as the AC current whose current value changes periodically. The output circuit 23 can also adjust the frequency of the AC power it outputs, and can change the AC power that serves as the test power to a plurality of frequencies that are different from each other. The output circuit 23 can also supply the DC power from the power storage device 21 to each of the electrochemical modules 2 without power conversion or the like.

[0028] In the embodiment, a diagnosis is performed on a plurality of electrochemical modules 2, and the following processing is performed in one diagnosis by the diagnostic device 10 or the like. In one diagnosis, the state of each of the plurality of electrochemical modules 2, such as the state of degradation, is diagnosed. Furthermore, the diagnosis of the electrochemical modules 2 is performed periodically. The processing circuit 11 executes the diagnostic program 16 each time a diagnosis is performed. In one diagnosis of the electrochemical modules 2, the processing circuit 11 causes one of the measurement circuits 5 corresponding to each of the plurality of electrochemical modules 2 to measure diagnostic measurement data. Then, the processing circuit 11 diagnoses the state of each of the electrochemical modules 2 by analyzing the measured diagnostic measurement data.

[0029] 2 is a flowchart showing an example of processing performed by the processing circuitry 11 and the like of the diagnostic device 10 when measuring diagnostic measurement data for each of the multiple electrochemical modules 2 of the diagnostic system 1. The processing of the example of FIG. 2 is performed each time a diagnosis is performed on the multiple electrochemical modules 2. The processing of the example of FIG. 2 is performed in a state where operating power is input to the multiple electrochemical modules 2 in parallel. That is, when the processing of the example of FIG. 2 is performed, operating power is input to each of the electrochemical modules 2. When the processing of the example of FIG. 2 starts, the processing circuitry 11 and the like assign one of the multiple electrochemical modules 2 to the module to be measured (S101). Then, the processing circuitry 11 and the like perform processing to measure diagnostic measurement data for the module to be measured (S102).

[0030] When measurement of diagnostic measurement data for the measurement target module is completed by the process of S102, the processing circuit 11 determines whether diagnostic measurement data has been measured for all of the multiple electrochemical modules 2 of the diagnostic system 1 (S103). If measurement data has been measured for all of the electrochemical modules 2 (S103-Yes), the process of the example of FIG. 2 ends. On the other hand, if there is a power storage facility 3 for which measurement data has not been measured (S103-No), the process returns to S101, and the processing circuit 11 assigns one of the multiple electrochemical modules 2 to the measurement target facility (S101). At this time, the electrochemical module 2 assigned to the measurement target module is changed from the previous assignment of the measurement target module. Furthermore, the measurement target module is assigned from the electrochemical modules 2 for which diagnostic measurement data has not been measured.

[0031] 2, the allocation of modules to be measured and the measurement of measurement data for the modules to be measured are repeated by sequentially changing the electrochemical modules 2 assigned to the modules to be measured until measurement data is measured for all of the electrochemical modules 2 in the diagnostic system 1. Also, in the example of FIG. 2, the allocation of modules to be measured in S101 and the measurement of diagnostic measurement data for the modules to be measured in S102 are each performed the same number of times as the number of electrochemical modules 2 provided in the diagnostic system 1.

[0032] Fig. 3 is a flowchart showing an example of a process for measuring measurement data for diagnosis of the measurement target module shown in Fig. 2. When the process of Fig. 3 starts, the processing circuit 11 etc. determine whether the remaining capacity of the power storage device 21 is equal to or greater than the reference capacity (S111). This determines whether the remaining capacity of the power storage device 21 is sufficient to output the test power from the output circuit 23. If the remaining capacity of the power storage device 21 is less than the reference capacity (S111-No), the process returns to S111. Therefore, the process waits until the remaining capacity of the power storage device 21 becomes equal to or greater than the reference capacity through charging with power input from the power grid 3.

[0033] If the remaining capacity of the power storage device 21 is equal to or greater than the reference capacity (S111-Yes), the processing circuit 11 changes the reference fluctuation range for the current value in the module to be measured from the first fluctuation range W1 to a second fluctuation range W2 that is larger than the first fluctuation range W1 (S112). At this time, the processing circuit 11 changes the reference fluctuation range from the first fluctuation range W1 to the second fluctuation range W2 by, for example, changing the settings in the PCS 6 corresponding to the module to be measured.

[0034] Then, the processing circuit 11 controls the operation of the output circuit 23 and the connection switching circuit 25 to start outputting and supplying the test power from the output circuit 23 to the electrochemical module 2 assigned to the module to be measured (S113). Here, while the test power is being supplied from the output circuit 23 to the module to be measured, DC power is input to the module to be measured as operating power. Therefore, by supplying the test power to the module to be measured, the test power is superimposed on the operating power to the module to be measured.

[0035] FIG. 4 illustrates the process of changing the reference fluctuation range for the current value in the module under measurement, shown in S112 of FIG. 3. FIG. 4 shows a graph with time t on the horizontal axis and current I on the vertical axis. FIG. 4 also shows the time change I(t) of the current input to the module under measurement when test power is superimposed on the operating power to the module under measurement. In the example shown in FIG. 4, the PCS 6 corresponding to the module under measurement adjusts the operating power input to the module under measurement so that the current value of the current input to the module under measurement falls within the reference fluctuation range centered on the target current value Itar. Then, the output circuit 23 outputs AC power as the test power, and the current value of the AC power being the test power periodically changes with a fluctuation range (peak-to-peak value) Wa.

[0036] In the example of FIG. 4 , when the test power is not superimposed on the operating power to the module under measurement, the processing circuit 11 sets a reference fluctuation range for the current value in the module under measurement to a first fluctuation range W1. Then, in cooperation with the PCS 6 corresponding to the module under measurement, the processing circuit 11 controls the current value of the current input to the module under measurement to fall within the range of the first fluctuation range W1, centered around the target current value Itar. On the other hand, when the test power is superimposed on the operating power to the module under measurement, the processing circuit 11 sets a reference fluctuation range for the current value in the module under measurement to a second fluctuation range W2, which is larger than the first fluctuation range W1. Then, in cooperation with the PCS 6 corresponding to the module under measurement, the processing circuit 11 controls the current value of the current input to the module under measurement to fall within the range of the second fluctuation range W2, centered around the target current value Itar.

[0037] As shown in Figure 4 and other figures, in this embodiment, the processing circuit 11 sets the second fluctuation range W2, which is the reference fluctuation range when the test power is superimposed on the operating power to the measurement target module, to be larger than the fluctuation range Wa of the current value of the AC power that serves as the test power. Also, in the example of Figure 4, the first fluctuation range W1, which is the reference fluctuation range when the test power is not superimposed on the operating power to the measurement target module, is set to be smaller than the fluctuation range Wa of the current value of the AC power that serves as the test power. However, the first fluctuation range W1 may be equal to or larger than the fluctuation range Wa of the current value of the AC power that serves as the test power, as long as it is smaller than the second fluctuation range W2.

[0038] In the example measurement process of FIG. 3 , when the supply of test power to the module to be measured is started by the process of S113, the processing circuit 11 measures the current and voltage of the electrochemical module 2 assigned to the module to be measured (S114). As a result, the current and voltage of the module to be measured are measured while the test power is superimposed on the operating power. At this time, for example, the current input to the module to be measured and the voltage applied to the entire module to be measured are measured as the current and voltage of the module to be measured. Furthermore, in a configuration in which multiple electrochemical cells are electrically connected in the module to be measured, the current flowing through each electrochemical cell while the test power is superimposed on the operating power may be measured as the current of the module to be measured, and the voltage applied to each electrochemical cell while the test power is superimposed on the operating power may be measured as the voltage of the module to be measured.

[0039] Furthermore, while measuring the current and voltage of the measurement target module, the processing circuit 11 superimposes the test power, which is AC power, on the operating power of the measurement target module while sequentially changing the test power to a plurality of mutually different frequencies. Then, while the test power is superimposed at each of the plurality of frequencies, the current and voltage of the measurement target module are measured. Then, unless the measurement of the current and voltage of the electrochemical module 2 assigned to the measurement target module is completed (S115-No), the process returns to S114, and the process of S114, i.e., the measurement of the current and voltage of the measurement target module, is continued. By measuring the current and voltage of the measurement target module as described above, measurement data for diagnosis is measured for the electrochemical module 2 assigned to the measurement target module.

[0040] When the measurement of the current and voltage for the module under measurement is completed (S115-Yes), the processing circuit 11 stops the output of the test power from the output circuit 23 to the module under measurement, and stops the supply of the test power to the module under measurement (S116). This results in a state in which the test power is not superimposed on the operating power to the module under measurement. The processing circuit 11 then returns the aforementioned reference fluctuation range for the current value in the module under measurement from the second fluctuation range W2 to the first fluctuation range W1 (S117). This narrows the reference fluctuation range for the current value in the module under measurement.

[0041] 2 and 3, in a state where operating power is input in parallel to a plurality of electrochemical modules 2, the processing circuit 11 sequentially changes the electrochemical module 2 in which the test power is superimposed on the operating power, and sequentially measures diagnostic measurement data for the plurality of electrochemical modules 2. As a result, for each of the electrochemical modules 2 provided in the diagnostic system 1, the current and voltage in a state where the test power is superimposed on the operating power are measured as diagnostic measurement data.

[0042] In the embodiments and the like, the processing circuit 11 performs diagnosis by analyzing the diagnostic measurement data measured as described above for each of the multiple electrochemical modules 2. FIG. 5 shows an example of processing in analyzing the diagnostic measurement data for one electrochemical module 2 performed by the processing circuit 11 of the diagnostic device 10. In the embodiments and the like, the diagnostic measurement data for the other electrochemical modules 2 is analyzed in the same manner as the example shown in FIG. 5. Note that the analysis of the measurement data may be performed sequentially starting from the electrochemical module 2 for which measurement data has been measured, or may be performed after measurement data has been measured for all of the electrochemical modules 2.

[0043] 5 is started, the processing circuit 11 analyzes the diagnostic measurement data to measure the frequency characteristics of the impedance of the electrochemical module 2 (S121). At this time, the impedance of the electrochemical module 2 is calculated based on the measurement results of the current and voltage at each of the multiple frequencies at which the current and voltage of the electrochemical module 2 are measured. By calculating the impedance of the electrochemical module 2 at the multiple frequencies, the frequency characteristics of the impedance of the electrochemical module 2 are measured. Note that as the frequency characteristics of the impedance of the electrochemical module 2, the frequency characteristics of the impedance of the entire electrochemical module 2 may be measured, or in a configuration in which multiple electrochemical cells are electrically connected in the electrochemical module 2, the frequency characteristics of the impedance of each electrochemical cell may be measured.

[0044] Furthermore, the processing circuit 11 calculates the resistance component and the like for the electrochemical module 2 based on the measurement results of the frequency characteristics of the impedance for the electrochemical module 2 (S122). In one example, the storage medium 12 stores an equivalent circuit model for the electrochemical module 2, and in the equivalent circuit model, electrical characteristic parameters including the resistance component for the electrochemical module 2 are set. The equivalent circuit model indicates the relationship between the set electrical characteristic parameters and the impedance, and indicates, for example, a relational equation for calculating the impedance for the electrochemical module 2 using the electrical characteristic parameters and frequency.

[0045] In calculating the resistance component and the like in the electrochemical module 2, the processing circuit 11 performs a fitting calculation using, for example, the relationship between the electrical characteristic parameters and impedance indicated by the equivalent circuit model and the measurement results of the impedance frequency characteristics for the electrochemical module 2. At this time, the fitting calculation is performed using the electrical characteristic parameters set in the equivalent circuit model including the resistance component for the electrochemical module 2 as variables, and the electrical characteristic parameters that become the variables are calculated. Furthermore, in the fitting calculation, the values ​​of the electrical characteristic parameters that become the variables are calculated so that the difference between the calculated value calculated using the relationship indicated by the equivalent circuit model and the measured value that is the measurement result is as small as possible, at each of the multiple frequencies at which the impedance is measured. The resistance component and the like for the electrochemical module 2 are calculated by calculating the electrical characteristic parameters through the fitting calculation.

[0046] Note that a method of performing fitting calculations using measurement results of the frequency characteristics of the battery's impedance and the relationship between the impedance and electrical characteristic parameters (circuit constants) shown in an equivalent circuit model of the battery, calculating the values ​​of the electrical characteristic parameters set in the equivalent circuit model, and calculating the resistance component of the battery is disclosed in Patent Document 3 (JP 2017-106889 A). In embodiments, the resistance component of the electrochemical module 2 may be calculated in the same manner as the calculation of the resistance component of the battery in Patent Document 3.

[0047] By calculating the resistance component of the electrochemical module 2, it becomes possible to determine the degradation state of the electrochemical module 2, for example, based on the amount of change in the calculated resistance component from the start of use of the electrochemical module 2. In this case, for example, the greater the amount of change in the calculated resistance component from the start of use of the electrochemical module 2, the higher the degree of degradation of the electrochemical module 2 is determined to be.

[0048] Furthermore, when a diagnosis is not being performed, the processing circuitry 11 executes the output control program 17 to control the power input to each of the electrochemical modules 2. FIG. 6 shows an example of processing performed by the processing circuitry 11 of the diagnostic device 10 to control the power input to one electrochemical module 2 when a diagnosis is not being performed. In embodiments, the power input to other electrochemical modules 2 is controlled in the same manner as the example shown in FIG. 6 when a diagnosis is not being performed. Furthermore, when a diagnosis is not being performed, the processing shown in the example shown in FIG. 6 is repeatedly performed over time.

[0049] 6 starts, the processing circuitry 11 and the like determine whether the operating power supplied to the electrochemical module 2 is equal to or less than a reference level (S131). A state in which the operating power is equal to or less than the reference level includes a state in which the input of operating power to the electrochemical module 2 is stopped, as well as a state in which operating power is input to the electrochemical module 2 at a level equal to or less than the reference level. The processing circuitry 11 acquires information about the operating power input to the electrochemical module 2 based on information from the distribution adjustment circuit 7, measurement results of current and voltage in the corresponding measurement circuit 5, or the like.

[0050] If the operating power to the electrochemical module 2 is equal to or lower than the reference level (S131-Yes), the processing circuit 11 causes DC power to be supplied from the power storage device 21 to the electrochemical module 2 (S132). At this time, the DC power from the power storage device 21 is input to the electrochemical module 2 without being converted by the output circuit 23 or the like. Therefore, based on the fact that the operating power supplied to the electrochemical module 2 is equal to or lower than the reference level, DC power from the power storage device 21 is supplied to the electrochemical module 2. On the other hand, if the operating power to the electrochemical module 2 is higher than the reference level (S131-No), the processing of S132 is not performed, and the example processing of FIG. 6 ends. Therefore, only operating power is input to the electrochemical module 2, and DC power from the power storage device 21 is not supplied.

[0051] As described above, in the embodiment, while operating power is being input to the electrochemical module 2, test power is supplied from the output circuit 23 to the electrochemical module 2, thereby superimposing the test power on the operating power. Then, while the test power is being superimposed on the operating power, the current and voltage of the electrochemical module 2 are measured to obtain diagnostic measurement data. Therefore, the results of measuring the current and voltage of the electrochemical module 2 while the test power is being superimposed on the operating power are analyzed as diagnostic measurement data, thereby appropriately inspecting the electrochemical module 2. Furthermore, because the measurement is performed while the test power is superimposed on the operating power, the diagnostic measurement data of the electrochemical module 2 is measured without stopping the operation of the electrochemical module 2. This allows the electrochemical module 2 to be appropriately inspected while continuing to operate. For example, it is possible to collect products of the electrochemical reaction in the electrochemical module 2 while measuring diagnostic measurement data of the electrochemical module 2.

[0052] In another embodiment, AC power whose current value changes periodically is output from the output circuit as test power, and the test power, which becomes AC power while being sequentially changed to a plurality of frequencies different from each other, is superimposed on the operating power. This makes it possible to appropriately measure the frequency characteristics of the impedance of the electrochemical module 2 based on the measurement results of the current and voltage of the electrochemical module 2 while the test power is superimposed on the operating power. By measuring the frequency characteristics of the impedance of the electrochemical module 2, it becomes possible to appropriately estimate the resistance component, etc. of the electrochemical module 2, and thus make it possible to appropriately determine the degradation state of the electrochemical module 2 and the degradation state, etc. of each of the one or more electrochemical cells that make up the electrochemical module 2.

[0053] Furthermore, in this embodiment, the PCS 6, which serves as a power regulator, adjusts the operating power input to the electrochemical module 2 so that the current value in the electrochemical module 2 falls within a reference fluctuation range centered on a target current value. When the inspection power is not superimposed on the operating power, the reference fluctuation range is set to a first fluctuation range W1, and when the inspection power is superimposed on the operating power, the reference fluctuation range is set to a second fluctuation range W2 that is larger than the first fluctuation range W1. The second fluctuation range W2, which is the reference fluctuation range when the inspection power is superimposed on the operating power, is set to be larger than the fluctuation range Wa of the current value of the AC power that serves as the inspection power. Therefore, when measurement data is being measured by superimposing the inspection power on the operating power, the impact of the superimposition of the inspection power on the power adjustment in the PCS 6 is appropriately reduced.

[0054] Furthermore, in one example of the embodiment, in a state where operating power is input in parallel to a plurality of electrochemical modules 2, the electrochemical module 2 that superimposes the inspection power on the operating power is sequentially changed, and diagnostic measurement data is sequentially measured for the plurality of electrochemical modules 2. Therefore, even when diagnosing a plurality of electrochemical modules 2, diagnostic measurement data for each of the plurality of electrochemical modules 2 can be appropriately measured while operating each of the plurality of electrochemical modules 2, and the plurality of electrochemical modules 2 can be appropriately inspected.

[0055] Furthermore, in one example of the embodiment, when the operating power supplied to the electrochemical module 2 is equal to or lower than a reference level, DC power is supplied from the power storage device 21 to the electrochemical module 2. Therefore, even in a state where the supply of operating power to the electrochemical module 2 through the power grid 3 is stopped or in a state where the level of operating power supplied to the electrochemical module 2 is low, the electrochemical module 2 can be operated appropriately.

[0056] In the above-described embodiment, an electrochemical reaction occurs in the electrochemical module 2 when operating power is input to the electrochemical module 2. However, in a modified example, the electrochemical module 2 may output operating power generated by the electrochemical reaction. In this case, each of the one or more electrochemical modules 2 supplies the output operating power, for example, through the power grid 3. In this modified example, each of the one or more electrochemical cells in the electrochemical module 2 includes an anode and a cathode, and at least one of the anode and the cathode includes a catalyst. The electrochemical module 2 outputs DC power, and the output DC power is converted into AC power within a voltage range and frequency range compatible with the power grid 3 through DC / AC conversion and transformation in a power regulator such as the PCS 6. The converted AC power is then supplied through the power grid 3.

[0057] In one example, the electrochemical module 2 includes one or more fuel cells as electrochemical cells. In the electrochemical module 2, a fuel such as hydrogen is supplied to the anode of each electrochemical cell, and oxygen is supplied to the cathode of each electrochemical cell. In each electrochemical cell, an electrochemical reaction occurs due to the supply of fuel and oxygen, and a current is output from the cathode (positive electrode) and input to the anode (negative electrode). This generates operating power in the electrochemical module 2. Therefore, when the electrochemical module 2 is provided with fuel cells, supplying oxygen and fuel to the electrochemical module 2 generates operating power to be output from the electrochemical module 2.

[0058] In this modification, the processing circuit 11 and the like cause the output circuit 23 to supply test power to the electrochemical module 2 while the electrochemical module 2 is outputting operating power, thereby superimposing the test power on the operating power. Then, while the test power is being superimposed on the operating power, the processing circuit 11 measures the current and voltage of the electrochemical module 2 to measure diagnostic measurement data. Therefore, in this modification, the results of measuring the current and voltage of the electrochemical module 2 while the test power is being superimposed on the operating power are analyzed as diagnostic measurement data, thereby appropriately inspecting the electrochemical module 2. Furthermore, because the measurement is performed while the test power is superimposed on the operating power, diagnostic measurement data for the electrochemical module 2 is measured without stopping the operation of the electrochemical module 2. This allows the electrochemical module 2 to be appropriately inspected while continuing to operate. For example, it is possible to output operating power generated by an electrochemical reaction from the electrochemical module 2 while measuring diagnostic measurement data for the electrochemical module 2.

[0059] In this modification, the PCS 6, which is a power regulator, adjusts the operating power output from the electrochemical module 2. The PCS 6 then adjusts the operating power so that the current value in the electrochemical module 2, i.e., the current value of the current output from the electrochemical module 2, falls within a reference fluctuation range centered on a target current value. In this modification as well, when the inspection power is not superimposed on the operating power, the reference fluctuation range is set to a first fluctuation range W1, and when the inspection power is superimposed on the operating power, the reference fluctuation range is set to a second fluctuation range W2 that is larger than the first fluctuation range W1. The second fluctuation range W2 is then set to be larger than the fluctuation range Wa of the current value of the AC power that serves as the inspection power. Therefore, in this modification as well, when measurement data is being measured by superimposing the inspection power on the operating power, the impact of the superimposition of the inspection power on the power adjustment by the PCS 6 is appropriately reduced.

[0060] In another modified example, a plurality of electrochemical modules 2 are provided, each outputting operating power generated by an electrochemical reaction. When the plurality of electrochemical modules 2 are outputting operating power in parallel, the electrochemical module 2 that superimposes the inspection power on the operating power is sequentially changed, and diagnostic measurement data is sequentially measured for the plurality of electrochemical modules 2. In this modified example, a connection adjustment circuit or the like is provided instead of the distribution adjustment circuit 7, and the connection adjustment circuit can switch the electrical connection state of each electrochemical module 2 to the power grid 3. When the plurality of electrochemical modules 2 are outputting operating power in parallel, the connection adjustment circuit combines the power from the plurality of electrochemical modules 2 and supplies the combined power through the power grid 3. In this modified example, diagnostic measurement data for each of the plurality of electrochemical modules 2 can be appropriately measured while each of the plurality of electrochemical modules 2 is being operated, and the plurality of electrochemical modules 2 can be appropriately inspected.

[0061] In at least one of the above-described embodiments or examples, while operating power is being input to or output from the electrochemical module, test power is supplied to the electrochemical module from an output circuit and the test power is superimposed on the operating power. Then, while the test power is superimposed on the operating power, the current and voltage of the electrochemical module are measured to obtain diagnostic measurement data. This makes it possible to provide a diagnostic device, diagnostic system, diagnostic method, and diagnostic program for an electrochemical module that enable appropriate testing of the electrochemical module without stopping operation of the electrochemical module.

[0062] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. The following are additional notes. [1] A diagnostic device for an electrochemical module in which at least one of an anode and a cathode is provided with a catalyst, and an electrochemical reaction occurs when operating power is input, or the module outputs operating power generated by the electrochemical reaction, an output circuit capable of outputting inspection power; a processor that, while the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, causes the output circuit to supply the test power to the electrochemical module, thereby superimposing the test power on the operating power, and, while the test power is being superimposed on the operating power, measures the current and voltage of the electrochemical module to measure measurement data for diagnosis; A diagnostic device comprising: [2] The diagnostic device of [1], wherein the processor measures the impedance of the electrochemical module based on the measurement results of the current and voltage of the electrochemical module measured as the measurement data for diagnosis. [3] The processor outputs AC power, the current value of which changes periodically, from the output circuit as the test power, and sequentially changes the test power to a plurality of frequencies different from each other while superimposing the AC power on the operating power; The processor measures the frequency characteristics of the impedance of the electrochemical module based on the measurement results of the current and the voltage of the electrochemical module. [2] Diagnostic equipment. [4] Further comprising a storage device capable of storing electricity; the output circuit converts DC power from the power storage device into the inspection power and outputs the inspection power to the electrochemical module. [1] Diagnostic device. [5] In the electrochemical module, the electrochemical reaction occurs in response to the supply of the operating power; the processor causes the DC power from the power storage device to be supplied to the electrochemical module based on the operational power supplied to the electrochemical module being equal to or lower than a reference level; [4] Diagnostic equipment. [6] Any one of the diagnostic devices according to [1] to [5]; the electrochemical module comprising the anode and the cathode, at least one of the anode and the cathode comprising the catalyst, wherein the electrochemical reaction occurs when the operating power is input, or the operating power generated by the electrochemical reaction is output, and the current and the voltage are measured by the diagnostic device in a state in which the inspection power is superimposed on the operating power by the diagnostic device, thereby measuring the measurement data for diagnosis; A diagnostic system comprising: [7] A power regulator is further provided which adjusts the operating power input to the electrochemical module or the operating power output from the electrochemical module, and adjusts the operating power so that the current value in the electrochemical module falls within a reference fluctuation range centered on a target current value; the processor of the diagnostic device sets the reference fluctuation range to a first fluctuation range when the test power is not superimposed on the operating power, and sets the reference fluctuation range to a second fluctuation range larger than the first fluctuation range when the test power is superimposed on the operating power. [6] diagnostic system. [8] The processor of the diagnostic device causes the output circuit to output AC power whose current value changes periodically as the test power, the processor sets the second fluctuation range, which is the reference fluctuation range in a state in which the test power is superimposed on the operating power, to be larger than a fluctuation range of a current value of the AC power that is the test power; [7] diagnostic system. [9] the electrochemical module comprises one or more electrochemical cells each comprising the anode and the cathode; Each of the one or more electrochemical cells is either a water electrolysis cell that electrolyzes water when the operating power is input, a P2C cell that electrolyzes carbon dioxide when the operating power is input, or a fuel cell that generates the operating power and outputs it when oxygen and fuel are supplied. [6] diagnostic system.

[10] A plurality of the electrochemical modules are provided, the processor of the diagnostic device, in a state in which the operating power is input to the plurality of electrochemical modules in parallel or in a state in which the operating power is output from the plurality of electrochemical modules in parallel, sequentially changes the electrochemical module in which the inspection power is superimposed on the operating power, and sequentially measures the measurement data for diagnosis for the plurality of electrochemical modules; [6] diagnostic system.

[11] A diagnostic method for an electrochemical module in which at least one of an anode and a cathode is provided with a catalyst, and an electrochemical reaction occurs when operating power is input, or the module outputs operating power generated by the electrochemical reaction, While the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, supplying inspection power from an output circuit to the electrochemical module, thereby superimposing the inspection power on the operating power; measuring a current and a voltage of the electrochemical module while the test power is superimposed on the operating power, thereby obtaining measurement data for diagnosis; A diagnostic method comprising:

[12] A diagnostic program for an electrochemical module in which at least one of an anode and a cathode is provided with a catalyst, and an electrochemical reaction occurs when operating power is input, or the module outputs operating power generated by the electrochemical reaction, the diagnostic program being configured to include the following in a computer: While the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, an inspection power is supplied to the electrochemical module from an output circuit, thereby superimposing the inspection power on the operating power; measuring a current and a voltage of the electrochemical module while the test power is superimposed on the operating power, thereby measuring measurement data for diagnosis; Diagnostic program.

Claims

1. an electrochemical module including an anode and a cathode, wherein at least one of the anode and the cathode includes a catalyst, wherein an electrochemical reaction occurs when operating power is input, or the electrochemical module outputs operating power generated by the electrochemical reaction; an output circuit capable of outputting AC power whose current value changes periodically as inspection power; a power regulator that adjusts the operating power input to the electrochemical module or the operating power output from the electrochemical module, and adjusts the operating power so that a current value in the electrochemical module falls within a reference fluctuation range centered on a target current value; a processor that, while the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, causes the output circuit to supply the test power to the electrochemical module, thereby superimposing the test power on the operating power, and measures the current and voltage of the electrochemical module while the test power is being superimposed on the operating power, thereby measuring diagnostic measurement data; and a processor that, while the test power is being superimposed on the operating power, sets the reference fluctuation range to be larger than the fluctuation range of the current value of the AC power that serves as the test power. A diagnostic system comprising:

2. The diagnostic system of claim 1 , wherein the processor measures impedance of the electrochemical module based on the measurement results of the current and the voltage of the electrochemical module measured as the measurement data for diagnosis.

3. the processor superimposes the test power, which becomes the AC power, on the operating power while sequentially changing the test power to a plurality of frequencies different from each other; The processor measures the frequency characteristics of the impedance of the electrochemical module based on the measurement results of the current and the voltage of the electrochemical module. The diagnostic system of claim 2.

4. Further comprising a storage device capable of storing electricity, the output circuit converts DC power from the power storage device into the inspection power and outputs the inspection power to the electrochemical module. The diagnostic system of claim 1.

5. In the electrochemical module, the electrochemical reaction occurs in response to the supply of the operating power; the processor causes the DC power from the power storage device to be supplied to the electrochemical module based on the operating power supplied to the electrochemical module being equal to or lower than a reference level; The diagnostic system of claim 4.

6. the processor of the diagnostic system sets the reference fluctuation range to a first fluctuation range when the test power is not superimposed on the operating power, and sets the reference fluctuation range to a second fluctuation range greater than the first fluctuation range when the test power is superimposed on the operating power. The diagnostic system of claim 1.

7. the electrochemical module comprises one or more electrochemical cells each comprising the anode and the cathode; each of the one or more electrochemical cells is any one of a water electrolysis cell that electrolyzes water by receiving the operating power, a P2C cell that electrolyzes carbon dioxide by receiving the operating power, and a fuel cell that generates the operating power by receiving oxygen and fuel. The diagnostic system of claim 1.

8. A plurality of the electrochemical modules is provided, the processor of the diagnostic system, in a state in which the operating power is input to the plurality of electrochemical modules in parallel or in a state in which the operating power is output from the plurality of electrochemical modules in parallel, sequentially changes the electrochemical module in which the inspection power is superimposed on the operating power, and sequentially measures the measurement data for diagnosis for the plurality of electrochemical modules; The diagnostic system of claim 1.

9. A diagnostic method for an electrochemical module in which at least one of an anode and a cathode is provided with a catalyst, and an electrochemical reaction occurs when an operating power is input, or the module outputs operating power generated by the electrochemical reaction, comprising: while the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, supplying AC power whose current value changes periodically as inspection power from an output circuit to the electrochemical module, thereby superimposing the inspection power on the operating power; measuring a current and a voltage of the electrochemical module while the test power is superimposed on the operating power, thereby obtaining measurement data for diagnosis; adjusting the operating power input to the electrochemical module or the operating power output from the electrochemical module so that the current value in the electrochemical module falls within a reference fluctuation range centered on a target current value; In a state where the inspection power is superimposed on the operating power, the reference fluctuation range is set to be larger than a fluctuation range of a current value of the AC power serving as the inspection power; A diagnostic method comprising:

10. A diagnostic program for an electrochemical module in which at least one of an anode and a cathode is provided with a catalyst, and an electrochemical reaction occurs when an operating power is input, or an operating power generated by the electrochemical reaction is output, the diagnostic program being configured to include the following in a computer: While the operating power is being input to the electrochemical module or the operating power is being output from the electrochemical module, AC power whose current value changes periodically is supplied to the electrochemical module from an output circuit as inspection power, thereby superimposing the inspection power on the operating power; measuring a current and a voltage of the electrochemical module while the inspection power is superimposed on the operating power, thereby measuring measurement data for diagnosis; adjusting the operating power input to the electrochemical module or the operating power output from the electrochemical module so that the current value in the electrochemical module falls within a reference fluctuation range centered on a target current value; In a state in which the inspection power is superimposed on the operating power, the reference fluctuation range is set to be larger than a fluctuation range of a current value of the AC power serving as the inspection power. Diagnostic program.

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