Monitoring system

Abstract

To provide a monitoring system that can handle abnormalities at appropriate timing depending on the various abnormality situations that occur in a fuel cell system.SOLUTION: A monitoring system acquires measurement values from each of the multiple sensors (S71). The monitoring system determines whether the measurement values acquired from each of the multiple sensors satisfy a first determination condition defined for each of the multiple sensors (S75). When the monitoring system determines that the measurement values do not satisfy the first determination condition (S75: YES), it calculates a multiplication value by multiplying the elapsed time during which the measurement values do not satisfy the first determination condition by a weighting coefficient defined for each of the multiple sensors (S77). The monitoring system determines whether a second determination condition is satisfied on the basis of the calculated multiplication value. When the monitoring system determines that the second determination condition is not satisfied, it performs abnormality processing.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a monitoring system for monitoring abnormalities in a fuel cell system. [Background technology]

[0002] In a fuel cell system, when an abnormality that is likely to affect safety is detected, it is necessary to quickly stop power generation operation. On the other hand, when an abnormality that is unlikely to affect safety is detected, it is preferable to continue power generation without immediately stopping power generation. This is because, when power generation is stopped in a fuel cell system, it usually takes a long time to restart power generation. Therefore, it is desirable for a monitoring system that monitors abnormalities that occur in a fuel cell system to be able to accurately detect abnormalities so that the user can take appropriate action.

[0003] The equipment abnormality notification device described in Patent Document 1 sequentially performs abnormality determination processing for each of abnormalities 1 to N, and if it determines that an abnormality exists, executes display processing to notify the user of the corresponding abnormality. Here, the abnormality determination processing for each of abnormalities 1 to N is executed in order of higher priority. As a result, if multiple abnormalities occur simultaneously, the display processing is executed in order of higher priority. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 1-272290 Summary of the Invention [Problem to be solved by the invention]

[0005] The appropriate timing for notifying the user in response to an abnormality occurring in the fuel cell system may differ for each of the multiple abnormalities. Furthermore, for example, if multiple abnormalities occur simultaneously, it may be necessary to notify the user more quickly than if each of the multiple abnormalities occurs individually. In response to these circumstances, the device abnormality alarm device described in Patent Document 1 may not be able to notify the user at an appropriate timing depending on the various abnormality situations.

[0006] An object of the present invention is to provide a monitoring system that can perform abnormality processing at appropriate timing in accordance with various abnormality occurrence situations in a fuel cell system. [Means for solving the problem]

[0007] The monitoring system of claim 1 is characterized by comprising: a fuel cell system including a fuel cell cell and piping connected to the fuel cell cell; one or more sensors provided in the fuel cell system; an acquisition means for acquiring measurement values ​​from each of the one or more sensors; a first judgment means for determining whether the measurement values ​​acquired from each of the one or more sensors by the acquisition means satisfy a first judgment condition specified for each of the one or more sensors; a first calculation means for calculating a multiplication value by multiplying the elapsed time during which the measurement value does not satisfy the first judgment condition by a weighting coefficient specified for each of the one or more sensors when the first judgment means determines that the measurement value does not satisfy the first judgment condition; a second judgment means for determining whether a predetermined second judgment condition is satisfied based on the multiplication value calculated by the first calculation means; and an abnormality processing means for performing abnormality processing when the second judgment means determines that the second judgment condition is satisfied.

[0008] The one or more sensors of the monitoring system of claim 2 may be a plurality of sensors, and may further include a second calculation means for calculating a cumulative value by adding up the multiple multiplication values ​​calculated for each of the multiple sensors by the first calculation means, and the second determination means may determine whether the cumulative value calculated by the second calculation means satisfies the second determination condition.

[0009] The monitoring system of claim 3 may further include a setting means for setting the first judgment condition for each operating state defined according to the operating time since the fuel cell system started operation, and the first judgment means may determine whether the measurement values ​​obtained from each of the one or more sensors satisfy the first judgment condition set by the setting means.

[0010] The monitoring system of claim 4 may further include a reset means that resets the cumulative value when the first determination means determines that all of the measurement values ​​obtained from each of the one or more sensors satisfy the first determination condition.

[0011] The monitoring system of claim 5 may further include a stop means for stopping operation of the fuel cell system when the second determination means determines that the second determination condition is satisfied.

[0012] The abnormality processing means of the monitoring system of claim 6 may include a notification means for notifying an abnormality relating to the fuel cell system.

[0013] The one or more sensors of the monitoring system of claim 7 may include at least one of a temperature sensor, a flow meter, and a voltmeter. [Effects of the Invention]

[0014] In the monitoring system of claim 1, the timing for determining an abnormality can be controlled for each of one or more sensors by setting a weighting coefficient for each of one or more sensors. Therefore, the monitoring system can handle abnormalities at appropriate timing according to the various abnormality occurrence situations in the fuel cell system.

[0015] The monitoring system of claim 2 can handle abnormalities more quickly when it is determined that the measurement values ​​of multiple sensors do not satisfy the first judgment condition at the same time than when it is determined that each of the measurement values ​​of the multiple sensors does not satisfy the first judgment condition individually.

[0016] The monitoring system of claim 3 can judge the measurement value using an appropriate first judgment condition according to the operating state.

[0017] The monitoring system of claim 4 can suppress the execution of abnormality processing when the state in which the measurement value does not satisfy the first judgment condition does not continue for a long period of time. In this case, the monitoring system can suppress the execution of abnormality processing when there is no problem with the operation of the fuel cell system.

[0018] The monitoring system of claim 5 can maintain the safety of the fuel cell system well.

[0019] The monitoring system of claim 6 can notify the user that an abnormality has occurred in the fuel cell system.

[0020] The monitoring system of claim 7 can accurately detect the occurrence of an abnormality in the fuel cell system. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating a monitoring system 1. [Figure 2] 10 is a table illustrating a monitoring parameter table. [Figure 3] 10 is a flowchart of a monitoring process. [Figure 4] 4 is a flowchart of the monitoring process, which is a continuation of FIG. 3. [Figure 5] 5 is a flowchart of the monitoring process, which is a continuation of FIG. 4. [Figure 6] 10 is a flowchart of a determination process. DETAILED DESCRIPTION OF THE INVENTION

[0022] A monitoring system 1 according to one embodiment of the present invention will be described below with reference to the drawings. These drawings are used to explain technical features that may be adopted by the present invention. Unless otherwise specified, the device structures described below are merely illustrative examples and are not intended to be limiting.

[0023] <Overview of Monitoring System 1> The monitoring system 1 has a fuel cell system 10 and a control box 30. The fuel cell system 10 is a system that uses fuel cell technology to simultaneously generate electric power and thermal energy. The fuel cell system 10 improves energy utilization efficiency by utilizing the thermal energy generated when generating electric power for hot water supply. The control box 30 is responsible for the control and monitoring functions of the fuel cell system 10. A controller 50 is connected to the control box 30. The controller 50 includes at least an input unit 51 and a display unit 52. The input unit 51 is a keyboard for inputting information. The display unit 52 is a display for displaying information.

[0024] <Fuel Cell System 10> The fuel cell system 10 is constructed around a fuel cell hot module 4. Pipes 4A, 4B, 4C, and 4D are connected to the fuel cell hot module 4. Pipe 4A supplies fuel gas to the fuel cell hot module 4. Pipe 4B supplies air to the fuel cell hot module 4. Pipe 4C supplies water to the fuel cell hot module 4. Pipe 4D supplies high-temperature exhaust gas discharged from the fuel cell hot module 4 to a heat exchanger 71.

[0025] A fuel gas flow sensor 009 is provided in the pipe 4A. The fuel gas flow sensor 009 measures the flow rate of fuel gas flowing through the pipe 4A. A fuel gas sensor 011 is provided in the pipe 4A near the connection with the fuel cell hot module 4. The fuel gas sensor 011 detects fuel gas leaks. An air flow sensor 104 is provided in the pipe 4B. The air flow sensor 104 measures the flow rate of air flowing through the pipe 4B.

[0026] Pipe 4C is provided with a water purifier 210, a tank 212, and a water flow sensor 215. The water purifier 210 purifies water. The tank 212 temporarily stores the water purified by the water purifier 210. The water stored in the tank 212 flows toward the fuel cell hot module 4 via pipe 4C. The water flow sensor 215 measures the flow rate of water flowing through pipe 4C between the tank 212 and the fuel cell hot module 4. A float switch 213 is provided in the tank 212. The float switch 213 measures the level of the water stored in the tank 212. Pipe 4D is provided with an exhaust temperature sensor 405. The exhaust temperature sensor 405 measures the temperature of the exhaust gas flowing through pipe 4D.

[0027] The pipes 4A, 4B, 4C, and 4D are provided with supply means (not shown). The supply means of the pipe 4A is, for example, a valve, and supplies fuel gas to the fuel cell hot module 4 via the pipe 4A. The supply means of the pipe 4B is, for example, a fan, and controls the supply of air to the fuel cell hot module 4. The supply means of the pipe 4C is, for example, a pump, and controls the supply of water to the fuel cell hot module 4. The supply means of the pipe 4D is, for example, a fan, and controls the supply of high-temperature exhaust gas to the heat exchanger 71.

[0028] The fuel cell hot module 4 includes an evaporation section 41, a reforming section 42, a combustion section 43, and a fuel cell stack 44.

[0029] Fuel gas is supplied to the evaporation section 41 via a pipe 4A, and water is supplied via a pipe 4C. In the evaporation section 41, the water is heated to generate steam. The mixture of fuel gas and steam is supplied to the reforming section 42. The evaporation section 41 is provided with a temperature sensor 401. The temperature sensor 401 measures the temperature inside the evaporation section 41.

[0030] In the reforming section 42, the fuel gas contained in the mixed gas supplied from the evaporating section 41 is reformed into hydrogen by a catalyst. The reformed mixed gas is supplied to the fuel cell stack 44. The reforming section 42 is provided with a temperature sensor 402. The temperature sensor 402 measures the temperature inside the reforming section 42.

[0031] The fuel cell stack 44 includes a plurality of stacked fuel cell units 400. Each fuel cell unit 400 generates electricity through an electrochemical reaction between the mixed gas supplied from the reforming unit 42 and the air supplied via the pipe 4B. The fuel cell stack 44 has an increased power production capacity by stacking a plurality of fuel cell units 400. The fuel cell stack 44 is provided with a temperature sensor 404. The temperature sensor 404 measures the temperature inside the fuel cell stack 44.

[0032] The combustion section 43 combusts the mixed gas that has not completely reacted in the fuel cell stack 44. The combustion section 43 is provided with a temperature sensor 403. The temperature sensor 403 measures the temperature inside the combustion section 43.

[0033] The electricity generated in the fuel cell stack 44 is output via power line 4E. Furthermore, high-temperature exhaust gas consisting of water vapor, nitrogen, etc. is generated by the electrochemical reaction occurring in the fuel cell stack 44. The exhaust gas is discharged to the heat exchanger 71 via pipe 4D.

[0034] The power line 4E is provided with an output measuring unit 304 and a power conditioner 305. The output measuring unit 304 measures the voltage and current output to the power line 4E. The power conditioner 305 converts the DC power output from the fuel cell stack 44 into AC power.

[0035] A hot water storage tank 72 is connected to the heat exchanger 71. The heat exchanger 71 exchanges heat between the hot water supplied from the hot water storage tank 72 and the high-temperature exhaust gas supplied from the fuel cell hot module 4 via piping 4D, thereby raising the temperature of the hot water. The heated hot water is returned to the hot water storage tank 72. The hot water in the hot water storage tank 72 is supplied to a demand destination as needed.

[0036] <Control Box 30> The control box 30 includes a CPU 31 and a storage unit 32 .

[0037] The CPU 31 controls the entire fuel cell system 10. The CPU 31 is connected to the supply means provided in each of the pipes 4A, 4B, 4C, and 4D, the fuel gas flow sensor 009, the fuel gas sensor 011, the air flow sensor 104, the float switch 213, the water flow sensor 215, the exhaust temperature sensor 405, the temperature sensors 401, 402, 403, and 404, the output measurement unit 304, and the memory unit 32. Hereinafter, the fuel gas flow sensor 009, the fuel gas sensor 011, the air flow sensor 104, the float switch 213, the water flow sensor 215, the exhaust temperature sensor 405, the temperature sensors 401, 402, 403, and 404, and the output measurement unit 304 are collectively referred to as the "plurality of measurement sensors 100." The CPU 31 can acquire measurement results from each of the plurality of measurement sensors 100 by receiving signals output from the plurality of measurement sensors 100.

[0038] The storage unit 32 includes volatile and nonvolatile storage elements. The storage unit 32 stores at least a monitoring processing program executed by the CPU 31, a monitoring parameter table (see FIG. 2), an abnormality determination threshold, a startup operation termination condition, a ramp-up operation termination condition, an automatic operation termination condition, and an accumulated value.

[0039] <Monitoring parameter table> The monitoring parameter table is referenced when the CPU 31 monitors whether or not an abnormality has occurred in the fuel cell system 10. In the monitoring parameter table, a judgment range and a weighting coefficient are set for each of the multiple measurement sensors 100 in the fuel cell system 10. The judgment range and weighting coefficient are defined for each of startup operation, ramp-up operation, and automatic operation. Start-up operation refers to the operating state immediately after the power to the fuel cell system 10 is turned on. Ramping-up operation refers to the operating state after startup operation is completed and until the temperature of the fuel cell hot module 4 rises to a level that is safe for starting power generation. Automatic operation refers to the operating state after startup operation is completed and the temperature of the fuel cell hot module 4 has risen and stabilized. The "No." in the table corresponds to the symbols assigned to each of the multiple measurement sensors 100 shown in FIG. 1.

[0040] The CPU 31 compares the measurement results of each of the multiple measurement sensors 100 with the judgment range in the monitoring parameter table, and determines that an abnormality has occurred if the measurement result exceeds the judgment range. Furthermore, when the CPU 31 determines that an abnormality has occurred based on the measurement results of one or more measurement sensors 100, it calculates a multiplication value by multiplying the elapsed time since the abnormality occurred by the weighting coefficient in the monitoring parameter table for each measurement sensor 100 whose measurement result has become abnormal. The CPU 31 calculates a cumulative value by adding the multiplication values ​​calculated for each measurement sensor 100. When the calculated cumulative value exceeds a predetermined abnormality judgment threshold (e.g., 600 seconds), the CPU 31 executes abnormality processing and operation stop processing. The details of the abnormality processing and operation stop processing will be described later. Note that FIG. 2 shows an example in which the abnormality judgment threshold is common to the startup operation, the ramp-up operation, and the automatic operation.

[0041] <Monitoring process> The monitoring process will be described with reference to Figures 3 to 6. The monitoring process is started when the CPU 31 reads and executes a program stored in the storage unit 32 of the control box 30.

[0042] The CPU 31 determines whether or not a user has detected an operation to turn on the power supply in order to start power generation and hot and cold water supply by the fuel cell system 10 (S11). If the CPU 31 determines that a power-on operation has not been detected (S11: NO), the process returns to S11. The CPU 31 continues to wait for an operation to turn on the power supply.

[0043] When the CPU 31 detects an operation to turn on the power (S11: YES), it controls the fuel cell system 10 to start startup operation (S13). Specifically, the CPU 31 controls the supply means of the pipe 4A to start supplying fuel gas to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4B to start supplying air to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4C to start supplying water to the fuel cell hot module 4. During startup operation, the fuel cell 400 does not generate electricity, and the fuel cell hot module 4 does not operate.

[0044] The CPU 31 acquires the judgment range and weighting coefficient corresponding to the startup operation from the monitoring parameter table (see FIG. 2) for each of the plurality of measurement sensors 100. The CPU 31 sets the acquired judgment range and weighting coefficient for each of the plurality of measurement sensors 100 as individual judgment criteria (S15). The judgment range of the individual judgment criteria is referred to as the "individual judgment range," and the weighting coefficient of the individual judgment criteria is referred to as the "individual weighting coefficient." The CPU 31 resets the cumulative value, which is a variable stored in the memory unit 32, by setting it to 0 (S17).

[0045] The CPU 31 determines whether to terminate the startup operation started in S13 (S21). For example, if the measurement values ​​of the multiple measurement sensors 100 do not satisfy a predetermined startup operation termination condition, the CPU 31 determines not to terminate the startup operation (S21: NO). More specifically, if the flow rates measured by the fuel gas flow sensor 009, the air flow sensor 104, and the water flow sensor 215 are all less than a predetermined flow rate, the CPU 31 determines not to terminate the startup operation. In this case, the CPU 31 repeatedly executes the determination process (see FIG. 6) at a predetermined determination cycle (1 s) (S23).

[0046] The determination process will be described with reference to Fig. 6. The CPU 31 acquires measurement values ​​measured by each of the measurement sensors 100 from the plurality of measurement sensors 100 (S71). The CPU 31 compares the acquired measurement values ​​with the individual determination ranges of the individual determination criteria set in S15 (see Fig. 3) (S73).

[0047] If at least one measurement value of the plurality of measurement sensors 100 exceeds the individual judgment range, the CPU 31 judges that an abnormality has occurred (S75: YES). The CPU 31 multiplies the individual weighting coefficient corresponding to the measurement sensor 100 judged to be abnormal among the individual judgment criteria by the judgment period (1 second) to calculate a multiplied value (S77). The multiplied value corresponds to the value obtained by multiplying the elapsed time (1 second) during which the measurement value exceeds the individual judgment range by the individual weighting coefficient.

[0048] The CPU 31 calculates multiplication values ​​for all of the measurement sensors 100 determined to have an abnormality in S75. The CPU 31 adds the calculated multiplication values ​​to the cumulative value and updates the cumulative value (S79). The CPU 31 ends the determination process and returns the process to the monitoring process (see FIG. 3).

[0049] On the other hand, if all the measurement values ​​of the plurality of measurement sensors 100 are within the individual determination range, the CPU 31 determines that no abnormality has occurred (S75: NO). In this case, the CPU 31 resets the cumulative value by setting it to 0 (S81). The CPU 31 ends the determination process and returns the process to the monitoring process (see FIG. 3).

[0050] As shown in FIG. 3, after the determination process (S23) during startup operation is completed, the CPU 31 reads out and acquires the cumulative value calculated in the determination process (see FIG. 6) from the storage unit 32. The CPU 31 compares the acquired cumulative value with an abnormality determination threshold (for example, 600 seconds). If the cumulative value is smaller than the abnormality determination threshold, the CPU 31 determines that the cumulative value is not abnormal (S25: NO). The CPU 31 returns the process to S21. If the startup operation is to be continued (S21: NO), the CPU 31 repeats the determination process at a determination cycle (1 second).

[0051] While the startup operation continues, if the cumulative value becomes equal to or greater than the abnormality determination threshold, the CPU 31 determines that the cumulative value is abnormal (S25: YES). The CPU 31 causes the fuel cell system 10 to execute abnormality processing (S27). In the startup operation abnormality processing, the CPU 31 notifies the display unit 52 by displaying information indicating that an abnormality has occurred during the startup operation.

[0052] Next, the CPU 31 causes the fuel cell system 10 to execute an operation shutdown process (S29). In the startup operation shutdown process, as an example, the CPU 31 controls the supply means of the pipe 4A to stop the supply of fuel gas to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4B to stop the supply of air to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4C to stop the supply of water to the fuel cell hot module 4. The CPU 31 ends the monitoring process.

[0053] When all of the measurement values ​​of the plurality of measurement sensors 100 satisfy the startup operation termination condition, the CPU 31 determines to terminate the startup operation (S21: YES). More specifically, the CPU 31 determines to terminate the startup operation when a predetermined time has elapsed while the temperature of the temperature sensor 401 is at or above a predetermined temperature. In this case, the CPU 31 advances the process to S31 (see FIG. 4).

[0054] 4, the CPU 31 controls the fuel cell system 10 to start start-up operation (S31). Specifically, the CPU 31 starts power generation by the fuel cell cells 400, thereby starting the operation of the fuel cell hot module 4. Note that during start-up operation, power is generated when the fuel cell hot module 4 is not sufficiently heated, and therefore power supply from the power line 4E is not permitted.

[0055] The CPU 31 acquires the determination range and weighting coefficient corresponding to the start-up operation from the monitoring parameter table (see FIG. 2) for each of the plurality of measurement sensors 100. The CPU 31 sets the acquired determination range and weighting coefficient for each of the plurality of measurement sensors 100 as individual determination criteria (S33).

[0056] The CPU 31 determines whether to terminate the start-up operation started in S31 (S37). If the measurement values ​​of the multiple measurement sensors 100 do not satisfy the start-up operation termination condition, the CPU 31 determines not to terminate the start-up operation (S37: NO). More specifically, if at least one of the temperatures measured by the temperature sensors 401 to 404 is below a predetermined temperature, the CPU 31 determines not to terminate the start-up operation. In this case, the CPU 31 repeatedly executes a determination process (see FIG. 6) at a determination cycle (1 s) (S39). The determination process executed during the start-up operation is the same as the determination process executed during the startup operation, and therefore a description thereof will be omitted.

[0057] After the determination process (S39) during start-up operation is completed, the CPU 31 reads out and acquires the cumulative value calculated in the determination process (see FIG. 6) from the storage unit 32. The CPU 31 compares the acquired cumulative value with an abnormality determination threshold (for example, 600 seconds). If the cumulative value is smaller than the abnormality determination threshold, the CPU 31 determines that the cumulative value is not abnormal (S41: NO). The CPU 31 returns the process to S37. If the start-up operation is to be continued (S37: NO), the CPU 31 repeats the determination process at a determination cycle (1 second).

[0058] While the start-up operation continues, if the cumulative value becomes equal to or greater than the abnormality determination threshold, the CPU 31 determines that the cumulative value is abnormal (S41: YES). The CPU 31 causes the fuel cell system 10 to execute abnormality processing (S27). In the abnormality processing of the start-up operation, the CPU 31 notifies the display unit 52 by displaying information indicating that an abnormality has occurred during the start-up operation.

[0059] Next, the CPU 31 causes the fuel cell system 10 to execute an operation shutdown process (S45). In the startup operation shutdown process, as an example, the CPU 31 controls the supply means of the pipe 4A to stop the supply of fuel gas to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4B to stop the supply of air to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4C to stop the supply of water to the fuel cell hot module 4. The CPU 31 also waits until the temperature sensors 401 to 404 each drop below a predetermined temperature. Thereafter, the CPU 31 stops power generation by the fuel cell 400, thereby stopping the operation of the fuel cell hot module 4. The CPU 31 ends the monitoring process.

[0060] The CPU 31 determines to end the startup operation when all of the measurement values ​​of the plurality of measurement sensors 100 satisfy the startup operation end condition (S37: YES). More specifically, the CPU 31 determines to end the startup operation when all of the temperatures measured by the temperature sensors 401 to 404 are equal to or higher than a predetermined temperature. In this case, the CPU 31 advances the process to S51 (see FIG. 5).

[0061] 5, the CPU 31 controls the fuel cell system 10 to start automatic operation (S51). Specifically, since the fuel cell hot module 4 has been sufficiently heated by start-up operation, the CPU 31 permits the supply of power from the power line 4E and the supply of hot water from the hot water storage tank 72.

[0062] The CPU 31 acquires the determination range and weighting coefficient corresponding to the autonomous driving from the monitoring parameter table (see FIG. 2) for each of the plurality of measurement sensors 100. The CPU 31 sets the acquired determination range and weighting coefficient for each of the plurality of measurement sensors 100 as individual determination criteria (S53).

[0063] The CPU 31 determines whether to end the automatic operation started in S51 (S57). For example, if the CPU 31 does not detect an operation to turn off the power, it determines not to end the automatic operation (S57: NO). In this case, the CPU 31 repeatedly executes the determination process (see S5) at a determination cycle (1 s) (S59). The determination process executed during automatic operation is the same as the determination process executed during startup operation and start-up operation, and therefore description thereof will be omitted.

[0064] After the determination process (S59) during automatic driving is completed, the CPU 31 reads out and acquires the cumulative value calculated in the determination process (see FIG. 6) from the storage unit 32. The CPU 31 compares the acquired cumulative value with an abnormality determination threshold (for example, 600 seconds). If the cumulative value is smaller than the abnormality determination threshold, the CPU 31 determines that the cumulative value is not abnormal (S61: NO). The CPU 31 returns the process to S57. If the automatic driving is to be continued (S57: NO), the CPU 31 repeats the determination process at a determination cycle (1 second).

[0065] While the automatic operation continues, if the cumulative value becomes equal to or greater than the abnormality determination threshold, the CPU 31 determines that the cumulative value is abnormal (S61: YES). The CPU 31 causes the fuel cell system 10 to execute abnormality processing (S63). In the abnormality processing of the startup operation, the CPU 31 notifies the display unit 52 by displaying information indicating that an abnormality has occurred during the automatic operation.

[0066] Next, the CPU 31 causes the fuel cell system 10 to execute an operation shutdown process (S65). In the automatic operation shutdown process, as an example, the CPU 31 controls the supply means of the pipe 4A to stop the supply of fuel gas to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4B to stop the supply of air to the fuel cell hot module 4. The CPU 31 also controls the supply means of the pipe 4C to stop the supply of water to the fuel cell hot module 4. The CPU 31 also waits until the temperature sensors 401 to 404 each drop below a predetermined temperature. Thereafter, the CPU 31 stops power generation by the fuel cell 400, thereby stopping the operation of the fuel cell hot module 4. The CPU 31 ends the monitoring process.

[0067] When the CPU 31 determines that the automatic operation is to be ended (S57: YES), the CPU 31 causes the fuel cell system 10 to execute the operation stop process (S65), and ends the monitoring process.

[0068] <Actions and Effects of This Embodiment> In the monitoring system 1, a weighting coefficient is set for each of the plurality of measurement sensors 100. This allows the monitoring system 1 to control the timing of determining an abnormality for each of the plurality of measurement sensors 100. Therefore, the monitoring system 1 can perform abnormality processing at appropriate timing according to various abnormality occurrence situations in the fuel cell system 10.

[0069] In the monitoring system 1, the measurement values ​​of each of the multiple measurement sensors 100 are compared with the individual judgment range (S73). If the measurement value exceeds the individual judgment range, a multiplication value obtained by multiplying the elapsed time and a weighting coefficient is calculated for each of the multiple measurement sensors 100 (S77), and the multiplication value is added to the cumulative value to update it (S79). If the updated cumulative value becomes abnormal below the abnormality judgment threshold (S25: YES, S41: YES, S61: YES), it is determined that an abnormality has occurred in the fuel cell system 10, and abnormality processing (S27, S43, S63) is executed.

[0070] For example, consider a case where, during automatic operation, the absolute flow rate values ​​of the fuel gas flow sensor 009, the air flow sensor 104, and the water flow sensor 215 exceed the upper limit of the determination range and the fuel gas sensor 011 detects a gas leak (S75: YES). In this case, for each of the fuel gas flow sensor 009, the air flow sensor 104, and the water flow sensor 215, the elapsed time (1 s) is multiplied by a weighting coefficient (1) to calculate a multiplication value ((1 x 1) x 3). Furthermore, for the fuel gas flow sensor 009, the elapsed time (1 s) is multiplied by a weighting coefficient (120) ((1 x 120)). Then, each of these values ​​is added (3 + 120 = 123), which is added to the cumulative value, and the cumulative value is updated (S79). If this state continues for 5 seconds, the determination process (see FIG. 6) is executed five times, and the cumulative value is updated as follows (S79): 246 (= 123 × 2) (2 s), 369 (= 123 × 3) (3 s), 492 (= 123 × 4) (4 s), and 615 (= 123 × 5) (5 s). Then, after 5 seconds have elapsed, it is determined that the cumulative value (= 615) is greater than the abnormality determination threshold (e.g., 600 seconds) (S61: YES), and abnormality processing (S63) and operation stop processing (S65) are executed. That is, the monitoring system 1 stops driving the fuel cell system 10 and issues a notification 5 seconds after the occurrence of the abnormality.

[0071] In this way, when the monitoring system 1 determines that the measurement values ​​of multiple measurement sensors 100 exceed the individual judgment range at the same time, it can handle the abnormality more quickly than when the measurement values ​​of multiple measurement sensors 100 are judged individually.

[0072] The monitoring system 1 sets individual judgment criteria for each operating state (start-up operation, ramp-up operation, and automatic operation) defined according to the operating time since the fuel cell system 10 started (S15, S33, S53). In this case, the monitoring system 1 can judge the measurement value using appropriate individual judgment criteria according to the operating state.

[0073] In the monitoring system 1, when all measurement values ​​of the multiple measurement sensors 100 are within the individual judgment range, it is determined that no abnormality has occurred (S75: NO) and the cumulative value is reset to 0 (S81). Therefore, the monitoring system 1 can suppress the execution of abnormality processing when the state in which the measurement values ​​exceed the individual judgment range does not continue for a long period of time. In this case, the monitoring system 1 can suppress the execution of abnormality processing when there is no problem with the operation of the fuel cell system 10.

[0074] In addition, if a measurement sensor 100 measures a measurement value that exceeds the judgment range and the weighting coefficient in the monitoring parameter table is "0," the product of the elapsed time and the weighting coefficient becomes "0." In this case, although the cumulative value is not affected, the condition that at least one measurement value of the multiple measurement sensors 100 exceeds the individual judgment range is met (S75: YES), and therefore the cumulative value is not reset. Therefore, for example, even if the measurement value of a measurement sensor 100 whose weighting coefficient is not set to "0" exceeds the judgment range and the cumulative value is updated to "X," and the measurement value of this measurement sensor 100 subsequently falls within the judgment range, the cumulative value remains "X" and is not reset if any measurement value of a measurement sensor 100 whose weighting coefficient is set to "0" exceeds the judgment range. In this way, the monitoring system 1 can more appropriately determine an abnormality by not resetting the cumulative value when at least one measurement value of the multiple measurement sensors 100 exceeds the individual judgment range.

[0075] Note that the monitoring system 1 may reset the cumulative value if there is a measurement sensor 100 that has measured a measurement value that exceeds the determination range and the weighting coefficient in the monitoring parameter table is "0."

[0076] When the cumulative value is equal to or greater than the abnormality determination threshold, the CPU 31 stops power generation by the fuel cell units 400 of the fuel cell stack 44, thereby stopping the operation of the fuel cell hot module 4 (S45, S65). This allows the monitoring system 1 to maintain the safety of the fuel cell system 10 in a satisfactory manner.

[0077] In the abnormality processing, the monitoring system 1 notifies the user by displaying the operating state (start-up operation, ramp-up operation, automatic operation) and information indicating that an abnormality has occurred on the display unit 52 (S27, S43, S63). In this way, the monitoring system 1 can notify the user that an abnormality has occurred in the fuel cell system 10.

[0078] The multiple measurement sensors 100 include a fuel gas flow sensor 009, a fuel gas sensor 011, an air flow sensor 104, a float switch 213, a water flow sensor 215, an exhaust temperature sensor 405, temperature sensors 401, 402, 403, 404, and an output measurement unit 304. Therefore, the monitoring system 1 can accurately detect the occurrence of an abnormality in the fuel cell system 10.

[0079] <Modification> The present invention is not limited to the above-described embodiment, and various modifications are possible. The fuel cell system 10 may be a system that does not have a hot water supply function and is only capable of supplying electric power. For example, if hydrogen is supplied as the fuel gas, the fuel cell hot module 4 of the fuel cell system 10 may not have the evaporator 41 and the reformer 42. The multiple measurement sensors 100 provided in the fuel cell system 10 are merely examples, and the present invention is not limited thereto.

[0080] The monitoring system 1 may determine whether an abnormality has occurred by comparing a multiplied value obtained by multiplying the elapsed time by a weighting coefficient with an abnormality determination threshold. For example, if a predetermined number or more of the measurement sensors 100 have measured values ​​indicating a multiplied value that indicates an abnormality equal to the abnormality determination threshold, the monitoring system 1 may determine that an abnormality has occurred and execute abnormality processing and operation shutdown processing. In this case, the cumulative value does not need to be calculated.

[0081] A different abnormality determination threshold may be defined for each operating state (startup operation, ramp-up operation, automatic operation). In the monitoring parameter table, a common determination range and weighting coefficient may be defined regardless of the operating state (startup operation, ramp-up operation, automatic operation). The operating states are not limited to three (startup operation, ramp-up operation, automatic operation) and may be four or more.

[0082] If the automatic operation termination condition is met in S57 (S57: YES), a determination process (see FIG. 6) may be executed during the execution of the operation stop process (S21). If the cumulative value calculated in the determination process is abnormal, the monitoring system 1 may transition from the operation stop process to an emergency stop process that urgently stops operation.

[0083] When the cumulative value becomes equal to or greater than the abnormality judgment threshold (S25: YES, S41: YES, S61: YES), the monitoring system 1 may select whether to perform abnormality processing (S23, S43, S63) or emergency stop processing depending on the type of the multiple measurement sensors 100 that measured measurement values ​​that exceed the individual judgment range.

[0084] If a predetermined number or more of the measurement values ​​of the plurality of measurement sensors 100 are within the individual determination range, the cumulative value may be reset to 0.

[0085] The abnormality determination threshold and each value in the monitoring parameter table may be changeable by a user inputting the values ​​via the input unit 51 of the controller 50. The abnormality determination threshold and each value in the monitoring parameter table may be switched as appropriate depending on the operating environment of the fuel cell system 10, the output power, and whether or not hot water is supplied.

[0086] The monitoring system 1 does not have to perform the operation stop process after notifying the user through the abnormality process. In this case, for example, the user may manually stop the operation of the fuel cell system 10.

[0087] <Other> The measurement sensor 100 is an example of a "sensor" of the present invention. The CPU 31 that performs the process of S71 is an example of an "acquisition means" of the present invention. The determination range of the monitoring parameter table is an example of a "first determination condition" of the present invention. The CPU 31 that performs the process of S75 is an example of a "first determination means" of the present invention. The CPU 31 that performs the process of S79 is an example of a "first calculation means" of the present invention. The CPU 31 that performs the processes of S25, S41, and S61 is an example of a "second determination means" of the present invention. The CPU 31 that performs the processes of S27, S29, S43, S45, S63, and S65 is an example of an "abnormality processing means" and "notification means" of the present invention. The CPU 31 that performs the process of S81 is an example of a "reset means" of the present invention. The CPU 31 that performs the processes of S29, S45, and S65 is an example of a "stop means" of the present invention. [Explanation of symbols]

[0088] 1: Surveillance system 4A, 4B, 4C, 4D: Piping 10: Fuel cell system 31: CPU 32: Storage section 100: Measurement sensor 400: Fuel cell

Claims

1. a fuel cell system including a fuel cell and a pipe connected to the fuel cell; one or more sensors provided in the fuel cell system; an acquisition means for acquiring a measurement value from each of the one or more sensors; a first determination means for determining whether the measurement values ​​acquired from the one or more sensors by the acquisition means satisfy a first determination condition defined for each of the one or more sensors; a first calculation means for calculating a multiplication value obtained by multiplying a time during which the measurement value does not satisfy the first determination condition by a weighting coefficient defined for each of the one or more sensors when the first determination means determines that the measurement value does not satisfy the first determination condition; a second determination means for determining whether a predetermined second determination condition is satisfied based on the multiplied value calculated by the first calculation means; an abnormality processing means for performing an abnormality processing when the second determination means determines that the second determination condition is satisfied; A monitoring system comprising:

2. the one or more sensors are a plurality of sensors; a second calculation means for calculating a cumulative value by adding up the multiplied values ​​calculated for each of the sensors by the first calculation means; The second determination means 2. The monitoring system according to claim 1, further comprising: a step of determining whether the cumulative value calculated by the second calculation means satisfies the second determination condition.

3. a setting unit that sets the first determination condition for each operating state defined according to an operating time since the fuel cell system started operating; The first determination means 2. The monitoring system according to claim 1, wherein it is determined whether the measurement values ​​acquired from the one or more sensors satisfy the first determination condition set by the setting means.

4. The monitoring system according to claim 2, further comprising a resetting means for resetting the cumulative value when the first determination means determines that all of the measurement values ​​acquired from each of the one or more sensors satisfy the first determination condition.

5. 2. The monitoring system according to claim 1, further comprising a stop means for stopping operation of the fuel cell system when the second determination means determines that the second determination condition is satisfied.

6. The abnormality processing means 2. The monitoring system according to claim 1, further comprising a notification means for notifying an abnormality in the fuel cell system.

7. The monitoring system of claim 1 , wherein the one or more sensors include at least one of a temperature sensor, a flow meter, and a voltmeter.

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