JP6143353B2 - FUEL CELL UNIT, ITS CONTROL PROGRAM, ITS CONTROL METHOD, AND FUEL CELL COGENERATION SYSTEM - Google Patents

Description

The present invention relates to a fuel cell such as a fuel cell unit and a fuel cell cogeneration system, and a control technique thereof.

  A fuel cell cogeneration system (hereinafter simply referred to as “FC system”) includes a fuel cell unit, recovers the heat of the fuel cell unit, and uses it for hot water supply or heating. . The fuel cell unit includes auxiliary equipment in addition to the fuel cell stack and the fuel reformer. Auxiliary equipment includes pumps, blowers, sensors, and the like. In the FC system including this fuel cell unit, the operation state of the fuel cell unit is monitored and proper operation is maintained.

With regard to the control of the fuel cell unit, it is known that a pump is used when the reforming water generated in the fuel cell stack is returned to the fuel processing unit to be processed, and a stable supply of the reforming water is achieved (for example, Patent Document 1 and Patent Document 2).

JP 2008-273822 A JP 2013-75821 A

  By the way, in an FC system including a fuel cell unit, water generated by a power generation reaction of a fuel cell stack is stored in a tank, and this water is used in a fuel reformer. A reforming water pump is used to transport reforming water from the tank to the fuel reformer.

  The fuel reformer reacts fuel (for example, city gas) and reformed water to generate hydrogen-rich reformed gas. Supply of reforming water is indispensable for the generation of reformed gas, and the supply amount greatly affects the generation of reformed gas. In other words, the abnormal operation of the reforming water pump affects the generation of the reformed gas, and it is essential for the system to avoid such an abnormal operation.

  Examples of the abnormal operation include stoppage of reforming water flow, underflow or overflow. This reformed water abnormality causes abnormalities in the FC system, such as pressure abnormality, temperature abnormality, fuel cell stack voltage abnormality, etc., leading to an abnormal stop.

  In such an abnormal stop, an error report, a request for a maintenance request from the user, and the like are performed, and processing such as resuming normal operation through procedures such as pump replacement is performed.

  However, even if an abnormal stop occurs, the cause of the stop includes various things from slight to severe. In severe cases, it is necessary to replace the pump. However, in minor cases, when the maintenance staff inspects, there are cases where the abnormality has already been resolved or no abnormality is recognized, and even if an abnormality is recognized, if an appropriate control action is performed, In some cases, the abnormality of the reforming water pump is resolved.

Therefore, in view of such a problem, the present invention is intended to self-resolve the abnormality and to normalize the operation at the time of abnormality.

In order to achieve the above object, a fuel cell unit of the present invention is a fuel cell unit including a reforming water pump that conveys reforming water, the flow rate monitoring means for monitoring the flow rate of the reforming water, and the flow rate An abnormal flow rate of the reforming water is determined from the monitoring output of the monitoring means, and when the abnormal flow rate occurs in the reforming water, the driving and stopping of the reforming water pump are repeated at predetermined timings within a unit time. intermittent operation, increases or decreases the operation of the pump output, have rows abnormal elimination control for driving the reforming water pump in normal time with different driving pattern include any or more of the inverted switching operation of the flow direction of the reforming water, And a control unit that repeats the abnormality elimination control until the flow rate when the reforming water pump is operating in the drive pattern becomes equal to or higher than a predetermined flow rate based on the monitoring result of the flow rate monitoring unit .

In the fuel cell unit, the flow rate monitoring means is either a flow meter that detects the flow rate of the reformed water that flows in the pipe line by the reformed water pump, or a pressure gauge that detects the pressure in the pipe line. or both may also contains do the.

  In the fuel cell unit, the control means may count the number of times of abnormality elimination control and output abnormality information when the number reaches a predetermined number.

In order to achieve the above object, a control program for a fuel cell unit according to the present invention is a control program that is executed by a computer mounted on a fuel cell unit including a reforming water pump that conveys reforming water. The flow rate of the water is monitored, an abnormality in the flow rate of the reforming water is determined from the flow rate monitoring information, and when the flow rate abnormality occurs in the reformed water, the reforming water pump Any of the intermittent operation that repeats driving and stopping, the pump output increasing / decreasing operation, the reversal switching operation of the reforming water flow direction, or the abnormality elimination for driving the reforming water pump with a driving pattern different from the normal one including two or more controls had lines, based on the monitoring result of the flow monitoring means, the flow rate at which the reforming water pump is operating in the driving pattern repeats the abnormal elimination control until a more constant flow process Causing the computer to perform.

  In the control program for the fuel cell unit, the number of times of abnormality elimination control may be counted, and abnormality information may be generated when the counted number reaches a predetermined number.

In order to achieve the above object, a control method for a fuel cell unit according to the present invention is a control method for a fuel cell unit including a reforming water pump that conveys reforming water, and monitors the flow rate of the reforming water, Intermittent operation that determines the flow rate abnormality of the reforming water from the flow rate monitoring information and repeats driving and stopping of the reforming water pump at predetermined timings within a unit time when the flow rate abnormality occurs in the reforming water , increase or decrease the operation of the pump output, have rows abnormal elimination control for driving the reforming water pump in normal time with different driving pattern include any or more of the inverted switching operation of the flow direction of the reforming water, flow monitoring Based on the monitoring result of the means, the abnormality elimination control is repeated until the flow rate when the reforming water pump is operating in the drive pattern becomes equal to or higher than a predetermined flow rate.

  In the fuel cell unit control method, the abnormality elimination control may be counted, and abnormality information may be generated when the count reaches a predetermined number.

In order to achieve the above object, a fuel cell cogeneration system according to the present invention is a fuel cell cogeneration system including a fuel cell unit including a reforming water pump that conveys reforming water. An abnormal flow rate of the reforming water is determined from a monitoring flow rate monitoring unit and a monitoring output of the flow rate monitoring unit, and when the abnormal flow rate occurs in the reforming water, the reforming is performed at a predetermined timing within a unit time. The reforming water pump is operated with a driving pattern different from normal operation including any one or more of an intermittent operation that repeats driving and stopping of the water pump, an increase / decrease operation of the pump output, and a reversal switching operation of the flow direction of the reforming water. There rows abnormal elimination control to be driven, on the basis of the result of monitoring the flow monitoring means, until the flow rate when the reforming water pump is operating in the driving pattern is equal to or greater than the certain flow rate And control means for repeating the normal elimination control.

In the fuel cell cogeneration system, the control unit may count the number of times of abnormality elimination control and output abnormality information when the number reaches a predetermined number.

  According to the present invention, the following effects can be obtained.

  (1) If the reforming water flow rate abnormality occurs, if the reforming water pump is abnormal, the abnormality can be self-resolved, so the number of error reports can be reduced, and the fuel cell unit and the The reliability of the system including the fuel cell unit can be improved.

  (2) Since the abnormality can be resolved by itself, the number of maintenance work can be reduced and the cost of the maintenance work can be reduced.

Other objects, features, and advantages of the present invention will become clearer with reference to the accompanying drawings and each embodiment.

1 is a diagram illustrating an FC system according to a first embodiment. It is a figure which shows an example of a fuel cell unit. It is a figure which shows an example of a control part and its hardware. It is a block diagram which shows the function of a control part. It is a figure which shows an example of the notification of a control state. It is a figure which shows an example of an abnormality log recording data table. It is a flowchart which shows an example of the process sequence of control of FC system. It is a flowchart which shows an example of the process sequence of abnormality elimination control. It is a flowchart which shows an example of the process sequence of the drive pattern of a reforming water pump. It is a timing chart which shows ON / OFF control of a reforming water pump. It is a flowchart which shows an example of the process sequence of the drive pattern of the reforming water pump which concerns on 2nd Embodiment. It is a timing chart which shows ON / OFF control of a reforming water pump. It is a timing chart which shows ON / OFF control of another reforming water pump. It is a timing chart which shows ON / OFF control of another reforming water pump. It is a timing chart which shows ON / OFF control of another reforming water pump. It is a timing chart which shows ON / OFF control of another reforming water pump. It is a timing chart which shows ON / OFF control of another reforming water pump.

[First Embodiment]

<System configuration>

  FIG. 1 shows an example of an FC system (fuel cell cogeneration system) according to the first embodiment.

  The FC system 2 includes a fuel cell unit 4 and, as an example, a hot water storage unit 6. The fuel cell unit 4 includes a fuel cell stack 8, a fuel processing device 10, a water tank 12, drainers 14-1 and 14-2, and a heat exchanger 16. The hot water storage unit 6 is provided with a hot water storage tank 20. A control unit 18 that controls the functional units of the fuel cell unit 4 and the hot water storage unit 6 is provided.

The fuel cell stack 8 includes, for example, a polymer electrolyte fuel cell (PEFC). The fuel cell stack 8 is supplied with the hydrogen-rich reformed gas G1 from the fuel processing apparatus 10, and the hydrogen H ₂ of the reformed gas G1 is separated into hydrogen ions H + and electrons e−. The hydrogen ions H + pass through the electrolyte and are combined with oxygen on the air electrode side to generate water (H ₂ O). The electron e− moves to the air electrode side through the conducting wire, and is taken out as generated energy. The generated water of the fuel cell unit 4 is led to the water tank 12 through the water path 22-1 and stored.

  The fuel processing apparatus 10 is an example of a fuel reforming unit. The fuel processing apparatus 10 includes a fuel processing unit 24 and a combustion unit 26. The fuel processing unit 24 is supplied with fuel F such as city gas, selective oxidized air Ai, and water from the water tank 12, and this water is supplied as reformed water W1, and generates hydrogen-rich reformed gas G1 from the fuel F. The fuel F is guided to the fuel processing unit 24 through the fuel path 28, and the selective oxidized air Ai is guided through the selective oxidized air path 30. The reformed water W1 is led as the reformed water to the combustion processing unit 24 through the water path 22-2. The combustion unit 26 burns the hydrogen-rich reformed offgas G2 supplied from the fuel cell stack 8 and supplies heat to the reforming reaction of the fuel processing apparatus 10. That is, the combustion is for supplying a heat amount of the reforming reaction of the fuel processing apparatus 10. The reformed gas G1 generated by the fuel processing apparatus 10 is supplied to the fuel cell stack 8 from the gas path 32-1.

The drainer 14-1 is an example of a drain wastewater treatment unit, condenses the drain D from the reformed offgas G2, and drains the drain D. In this embodiment, a drainer 14-1 is installed in a gas path 32-2 installed between the fuel cell stack 8 and the combustion unit 26, and the reformed off-gas G2 passes from the fuel cell stack 8 through the drainer 14-1. It flows to the combustion unit 26. The reformed off gas G2 contains a large amount of drain D. The drain D is water remaining as an unreacted portion of the reformed water W1 supplied excessively for the reforming reaction in the fuel processing unit 24, or water (H ₂ O) generated by the power generation reaction.

  The combustion section 26 is provided with an exhaust path 34, and the exhaust path 34 is provided with a drainer 14-2. In this drainer 14-2, the condensed water obtained from the combustion exhaust gas G3 generated in the combustion section 26 is separated, and the combustion exhaust gas G3 excluding this condensed water is released to the outside air, and the condensed water is discharged into the water tank through the water path 22-3. 12 leads to.

  The heat exchanger 16 is installed in the exhaust path 34, and the heat of the combustion exhaust gas G3 is heat exchanged with the water W2 on the hot water storage unit 6 side. Thereby, the heat of combustion exhaust gas G3 is collect | recovered and utilized for the water W2. Hot water is stored in the hot water storage tank 20 as high-temperature water.

  The control unit 18 is an example of a control unit of the FC system 2. The control unit 18 is constituted by a computer, for example. The control unit 18 receives information from various sensors installed in the functional unit of the fuel cell unit 4 and gives a control output to functional units such as the fuel cell stack 8, the fuel processing unit 24, and the combustion unit 26. This control includes abnormality elimination control including a drive pattern different from the normal time.

  FIG. 2 shows an example of the fuel cell unit 4. The same parts as those in FIG. 1 are denoted by the same reference numerals.

  The fuel cell stack 8 is provided with a stack voltmeter 36. The stack voltmeter 36 is an example of voltage detection means, and detects the power generation voltage of the fuel cell stack 8. A gas inlet 32-1 for supplying the reformed gas G1 to the fuel cell stack 8 is provided with a stack inlet pressure gauge 42-1. The stack inlet pressure gauge 42-1 is an example of a means for monitoring the stack inlet side pressure, and detects the inlet pressure of the fuel cell stack 8. Detection information of these voltages and pressures is provided to the control unit 18.

  The water path 22-2 is provided with a reforming water pump 38, a reforming water flow meter 40-1, and a reforming water path pressure gauge 42-2. The reforming water pump 38 is an example of a reforming water transport unit. For example, a plunger pump is used as the reforming water pump 38. The reforming water W1 stored in the water tank 12 is transported through the water path 22-2 by the reforming water pump 38 and guided to the fuel processing unit 24. The reforming water flow meter 40-1 is an example of a flow rate monitoring unit that monitors the reforming water flow rate. In this embodiment, the reforming water flow meter 40-1 detects the flow rate of the reforming water W1. The reforming water path pressure gauge 42-2 is an example of a flow rate monitoring means as well as a path pressure monitoring means for the water path 22-2. In this embodiment, the pressure of the water path 22-2 is detected. . The flow rate and pressure detection information is provided to the control unit 18. That is, the detection outputs of the reforming water flow meter 40-1 and the reforming water path pressure gauge 42-2 may be used for flow rate monitoring.

  The fuel processing unit 24 includes a pressure gauge 42-3 and a temperature sensor 44. The pressure gauge 42-3 is an example of a processing pressure monitoring unit in the fuel processing unit 24, and detects the processing pressure. The temperature sensor 44 is an example of a temperature detection unit and detects temperature. For the temperature sensor 44, for example, a thermistor or a thermocouple is used. Detection information of these pressures and temperatures is provided to the control unit 18.

  The combustion unit 26 includes a thermocouple 46 and a frame rod 48. The thermocouple 46 is an example of a temperature detection unit. The frame rod 48 is an example of combustion monitoring means. When the thermocouple 46 detects an abnormal temperature, the system is stopped.

  The fuel path 28 is provided with a fuel blower 50, a fuel flow meter 40-2, and a fuel path pressure gauge 42-4. The fuel blower 50 is an example of a means for conveying the fuel F to the fuel processing unit 24. The fuel flow meter 40-2 is an example of a flow monitoring unit for the fuel F, and detects the flow rate of the fuel F. The fuel path pressure gauge 42-4 is an example of a path pressure monitoring unit for the fuel path 28, and detects the path pressure. The flow rate and pressure detection information is provided to the control unit 18.

  The selective oxidation air passage 30 is provided with a selective oxidation air blower 52, a selective oxidation air flow meter 40-3, and an air passage pressure gauge 42-5. The selective oxidation air blower 52 is an example of a means for conveying the selective oxidation air Ai to the fuel processing unit 24. The selective oxidation air flow meter 40-3 is an example of a flow rate monitoring unit for the selective oxidation air Ai, and detects the flow rate of the selective oxidation air Ai. The air path pressure gauge 42-5 is an example of a path pressure monitoring unit for the selective oxidation air path 30, and detects the path pressure. The flow rate and pressure detection information is similarly provided to the control unit 18.

<Control unit 18>

  FIG. 3A shows an example of the control unit 18. A display unit 54 and an error notification unit 56 are connected to the control unit 18. The display unit 54 may use, for example, an LCD (Liquid Crystal Display) display that presents visual information. An indicator or the like is used for the error notification unit 56.

  The pump drive unit 58 receives the control output of the control unit 18 and drives the reforming water pump 38. The drive pattern of the reforming water pump 38 includes a normal drive pattern and a drive pattern that is different from the normal drive pattern when a flow rate abnormality occurs in the reformed water W1. A drive pattern different from that in the normal state is executed by abnormality elimination control.

  FIG. 3B illustrates an example of hardware of the control unit 18. For example, a computer is used for the control unit 18, and a processor 60, a ROM (Read-Only Memory) 62, an NVM (Non Volatile Memory) 64, a RAM (Random-Access Memory) 66, an input unit 68, an output unit 70, and A display control unit 72 and a pump control unit 74 are included.

  The processor 60 executes various programs such as an OS (Operating System) and firmware stored in the ROM 62, and performs various types of information processing. This information processing includes the above-described abnormality elimination control processing. The ROM 62 stores various programs such as an OS and firmware. The NVM 64 is an example of data storage means, and uses, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory). In this NVM 64, a database such as an abnormality history recording data table 102 (FIG. 6) is constructed. The RAM 66 is used as a work area for information processing. The input unit 68 is used for capturing detection information and the like. The output unit 70 outputs control information, drive outputs of various functional units, and error notification information.

  The display control unit 72 performs display control of the display unit 54 under the control of the processor 60. The control output of the display control is given to the display unit 54.

  The pump control unit 74 performs drive control of the reforming water pump 38 under the control of the processor 60. This drive control includes drive pattern control in a normal state and drive pattern control different from that in a normal state when a flow rate abnormality occurs in the reforming water W1.

<Function of control unit 18>

  FIG. 4 shows the function 76 of the control unit 18. This function 76 includes an abnormality detection function 78, a system stop function 80, a flow rate abnormality determination function 82, an abnormality elimination control function 84, an abnormality elimination control count function 86, a status notification function 88, and an abnormality history recording function 90.

  The abnormality detection function 78 receives detection outputs from various sensors such as the stack voltmeter 36 and detects an abnormality of the FC system 2.

  The system stop function 80 stops the drive of the FC system 2 when the abnormality detection function 78 detects the abnormality.

  The flow rate abnormality determination function 82 receives the detection output of the reforming water flow meter 40-1 or the reforming water path pressure gauge 42-2 received by the abnormality detection function 78, and determines the flow rate abnormality of the reforming water W1.

  The abnormality elimination control function 84 executes the abnormality elimination control based on the flow rate abnormality determination of the flow rate abnormality determination function 82. This abnormality elimination control includes drive pattern control different from the above-described normal time. In this drive pattern control, the pump drive unit 58 is driven by a drive pattern control different from that in the normal state, and based on this, the reforming water pump 38 operates, for example, intermittently or changes the transport direction.

  The abnormality elimination control count function 86 counts the number and time of the abnormality elimination control executed by the abnormality elimination control function 84. For example, the number of times of abnormality elimination control is counted in units of abnormality elimination control for a predetermined time, or the number of drive pattern pulses used for abnormality elimination control is counted.

  The state notification function 88 notifies the operation state including the system abnormality of the FC system 2. In this case, when the abnormality elimination control function 84 is being executed, it is notified that the abnormality elimination control is being executed. When the abnormality that triggered the abnormality elimination control is eliminated by the abnormality elimination control, the abnormality elimination is notified and the fact that the abnormality has been normally eliminated is notified.

  The abnormality history recording function 90 records the abnormality history in the abnormality history recording data table 102 (FIG. 6) stored in the NVM 64.

<Notification of control status>

  FIG. 5 shows an example of a control state notification including an abnormality notification. This control state information display is displayed on the display screen 92 of the display unit 54.

  FIG. 5A shows a screen display when the flow rate of reforming water is abnormal. On the display screen 92, a message 94 indicating the occurrence of an abnormality in the flow rate of the reforming water W1 and the execution of the abnormality elimination control is displayed. In this message 94, for example, “An abnormality in the flow rate of reforming water has occurred, and abnormality elimination control is executed.” Is displayed. According to this message 94, it is possible to immediately know that the user shifts to the abnormality elimination control when the reforming water flow rate abnormality occurs.

  FIG. 5B shows a screen display during the execution of the abnormality elimination control. On the display screen 92, a message 96 indicating that the abnormality elimination control is being executed is displayed. In this message 96, “execution of abnormality elimination control” is displayed as an example. According to this message 96, it is possible to immediately know that the user is under the abnormality elimination control.

  C in FIG. 5 shows a screen display of the control result of the abnormality elimination control. The display screen 92 displays a message 98 indicating the execution of the abnormality elimination control and the result thereof. As an example, the message 98 displays “Returned to normal as a result of abnormality elimination control”. According to this message 98, the user can immediately know that the FC system 2 has returned to normal as a result of the abnormality elimination control.

  FIG. 5D shows a screen display of the control result of another abnormality elimination control. The display screen 92 displays a message 100 representing the execution of the abnormality elimination control and the result thereof. In this message 100, for example, “an abnormality in the flow rate of reforming water is not resolved even by the abnormality elimination control. The system is stopped.” Is displayed. According to this message 100, the user can immediately know that the FC system 2 is not normalized as a result of the abnormality elimination control, and that the system shifts to the system stop.

<Abnormality history recording data table 102>

  FIG. 6 shows an example of the abnormality history record data table 102. The abnormality history record data table 102 is an example of a database stored in the NVM 64 that is one recording medium.

  As an example, the abnormality history record data table 102 stores data number 104, date / time 106, abnormality detection 108, control mode 110, number of times 112, error notification 114, and current status information 116.

  The data number 104 is an identification number of stored data. The date / time 106 is the calendar date and time when the abnormality occurred. In this embodiment, no. As an example, the data No. 1 stores “2013.09.10 0:00”. In the data of 2, as an example, 2013.9.2.25 9:00 is stored. The abnormality detection 108 indicates the type of abnormality detected. The control form 110 shows a control form corresponding to the abnormality. This control form includes, for example, the drive pattern of the reforming water pump 38. The number of times 112 is, for example, the number of times of abnormality elimination control. The error notification 114 indicates the presence / absence of abnormality notification. The current state information 116 represents the current control state as a result of abnormality detection.

  This abnormality history record data table 102 is information that can be displayed as visual information on the above-described display screen 92 and notified.

<Control of FC system 2>

  FIG. 7 shows an example of a processing procedure for control of the FC system 2. This processing procedure is an example of the control program or the control method of the present invention.

  In this processing procedure, normal operation is performed (S11), and abnormality detection of the FC system 2 is performed in this normal operation (S12). If there is no abnormality (NO in S12), normal operation is continued and abnormality detection is continued.

  If there is an abnormality in the FC system 2 (YES in S12), it is determined whether or not the FC system 2 is stopped (S13). When the FC system 2 is not stopped (NO in S13), normal operation is continued.

  If the FC system 2 is stopped (YES in S13), it is determined whether the detected abnormality is an abnormality in the flow rate of the reforming water W1 (S14). If the flow rate of the reforming water W1 is abnormal (YES in S14), the abnormality elimination control of the reforming water pump 38 is executed (S15). In this abnormality elimination control, the reforming water pump 38 is driven with a driving pattern different from that in the normal state.

  When this abnormality elimination control is executed, for example, the number of times of the control is counted (S16). It is determined whether this count number is equal to or greater than a predetermined number (S17). If it is less than the predetermined number (NO in S17), the process returns to S11 and the processes of S11 to S17 are performed. In this case, if it is less than the predetermined number, the control that returns to S11 is less than the predetermined number of abnormality elimination control, that is, even if the abnormality elimination control is performed once, the abnormal operation of the reforming water pump 38 is eliminated and normal. It is assumed that driving is possible.

  If the count number reaches a predetermined number or more (YES in S17), an error is issued (S18). That is, even if the error elimination control is repeated, the abnormality is not eliminated, and it is determined that continuation of the abnormality elimination control over a predetermined number is meaningless, and an error is issued. This error notification is performed by the aforementioned notification of the control state (FIG. 5). By this error notification, the user can recognize the abnormality.

  If the flow rate of the reforming water W1 is not abnormal in S14 (NO in S14), an error is issued without performing abnormality elimination control, that is, jumping through S15, S16, and S17. In the case of an abnormality that cannot be solved by the abnormality elimination control, it is possible to avoid useless abnormality elimination control and to speed up the processing.

<Abnormality elimination control of reforming water pump 38>

  FIG. 8 shows a processing procedure for abnormality elimination control of the reforming water pump 38. This processing procedure is a subroutine of the processing procedure shown in FIG.

  In this processing procedure, ON / OFF control of the reforming water pump 38 is performed (S21). This ON / OFF control executes a drive pattern different from the normal drive pattern.

  In this ON / OFF control, it is monitored whether the flow rate of the reforming water W1 during the operation of the reforming water pump 38 is a predetermined flow rate or higher or a predetermined pressure or higher (S22). It is determined whether the flow rate per minute is a constant flow rate, for example, 2 [cc / min] or more, or the constant pressure is, for example, a pressure in the path, for example, 4 [kPa] or more.

  If the flow rate of the reforming water W1 during the operation of the reforming water pump 38 is less than a certain flow rate or less than a certain pressure (NO in S22), the ON / OFF control is continued.

  If the flow rate of the reforming water W1 during the operation of the reforming water pump 38 is equal to or higher than a predetermined flow rate or higher than a predetermined pressure (YES in S22), the abnormality elimination control of the reforming water pump 38 is completed (S23). . Then, the abnormality history is recorded (S24), and the process returns to S15 (FIG. 7).

<Driving pattern of reforming water pump 38>

  FIG. 9 shows a procedure for processing the drive pattern of the reforming water pump 38.

  The ON / OFF control of the reforming water pump 38 is based on the end time te from the start time ts. In this processing procedure, time ts <t <t1: pump output P = 0 [%] is set (S31). After the elapse of time t1, time t1 ≦ t <t2: pump output P = 30 [%] is set (S32). After the elapse of time t2, time t2 ≦ t <t3: pump output P = 0 [%] is set (S33). After the elapse of time t3, time t3 ≦ t <t4: pump output P = 70 [%] is set (S34). After the elapse of time t4, time t4 ≦ t <t5: pump output P = 0 [%] is set (S35). After the elapse of time t5, time t5 ≦ t <t6: pump output P = 50 [%] is set (S36). After the elapse of time t6, time t6 ≦ t <t7: pump output P = 0 [%] is set (S37). After the elapse of time t7, time t7 ≦ t <t8: pump output P = 100 [%] is set (S38). After the elapse of time t8, time t8 ≦ t <te: pump output P = 0 [%] is set (S39).

  Such pump output P = 0 [%], 30 [%], 0 [%], 70 [%], 0 [%], 50 [%] 0 [%], 100 [%], 0 [%] Abnormality elimination control is performed by ON / OFF control in units of.

  With this drive pattern, an output pattern is obtained in the reforming water pump 38 as shown in FIG. FIG. 10 shows the output pattern with time on the horizontal axis and pump output on the vertical axis.

  In this case, the reforming water pump 38 is intermittently turned ON / OFF, and the pump output is changed every ON / OFF. In this ON / OFF control, the ON time or OFF time may not be constant, and may be different.

<Effect of the first embodiment>

  According to the first embodiment, the following effects can be obtained.

  (1) In the FC system 2, for example, when the FC system 2 becomes abnormal due to a malfunction of the reforming water pump 38 using the plunger pump, the abnormality eliminating control of the reforming water pump 38 System abnormalities can be resolved.

  (2) In this case, maintenance work such as pump replacement for eliminating the abnormality of the FC system 2 due to the abnormality of the reforming water pump 38 can be reduced. That is, the abnormality of the reforming water pump 38 can be restored to the normal operation by the abnormality elimination control, and the maintenance work required for error notification and minor malfunction can be eliminated.

  (3) In this embodiment, the operation of the reforming water pump 38 is monitored and an abnormality is detected. That is, if an abnormality of the FC system 2 is detected, abnormality elimination control for changing the output of the reforming water pump 38 is performed.

  (4) After this error elimination control, normal operation is performed. If no abnormality is detected by the transition to the normal operation, the operation is continued as a normal operation. On the other hand, when the abnormality detection state is repeated a specific number of times, an error is issued and the system is checked. As a result, the number of inspections can be reduced.

  (5) By repeating the error elimination control and the normal operation control, minor anomalies can be removed, and an appropriate response according to the judgment result can be taken.

  (6) The number of errors and notifications can be reduced, system reliability can be improved, maintenance work can be reduced, and costs can be reduced.

[Second Embodiment]

  FIG. 11 shows the abnormality elimination control of the reforming water pump 38 according to the second embodiment.

  In the abnormality elimination control of the above-described embodiment, the direction in which the reforming water W1 is conveyed by the reforming water pump 38 is set to one direction. The direction and the opposite direction are repeated alternately.

  In this processing procedure, time ts <t <t11: pump output P = 0 [%] is set (S41). After the elapse of time t11, time t11 ≦ t <t12: pump output P = −30 [%] is set (S42). In this case, a pump output of P = −30 [%] is given in the direction opposite to the normal conveyance direction.

  After the elapse of time t12, time t12 ≦ t <t13: pump output P = 0 [%] is set (S43). After the elapse of time t13, time t13 ≦ t <t14: Pump output P = 70 [%] is set (S44). That is, switching from the reverse direction to the normal conveyance direction is performed, and the pump output P = 70 [%] is set.

  After the elapse of time t14, time t14 ≦ t <t15: pump output P = 0 [%] is set (S45). After the elapse of time t15, time t15 ≦ t <t16: pump output P = −60 [%] is set (S46). Here, the conveyance direction is reversed.

  Then, after the elapse of time t16, time t16 ≦ t <t17: pump output P = 0 [%] is set (S47). After the elapse of time t17, time t17 ≦ t <t18: pump output P = 100 [%] is set (S48). After the elapse of time t18, time t18 ≦ t <te: pump output P = 0 [%] is set (S49).

  Such pump output P = 0 [%], -30 [%], 0 [%], +70 [%], 0 [%], -60 [%], 0 [%], 100 [%], 0 Abnormality elimination control is performed by ON / OFF control in units of [%].

  With this drive pattern, an output pattern is obtained in the reforming water pump 38 as shown in FIG. FIG. 12 shows the output pattern with time on the horizontal axis and pump output on the vertical axis.

  Also in this embodiment, the reforming water pump 38 is intermittently turned ON / OFF, and the pump output is changed every ON / OFF. In this ON / OFF control, the ON time or OFF time may not be constant, and may be different.

[Other Embodiments]

  (1) In the abnormality elimination control of the above embodiment, the set pressure value is set to the same value for a certain period of time for the ON / OFF control of the reforming water pump 38. As shown in FIG. You may make it intermittent with a period shorter than the period of ON / OFF control.

  (2) For ON / OFF control of the reforming water pump 38, the pump output may be changed in a half-wave waveform of a sine wave as shown in FIG. 14, and the pump output is sawtooth-shaped as shown in FIG. You may change with a waveform. Moreover, as shown in FIG. 16 or FIG. 17, the conveyance direction of the reforming water may be alternately changed with such a drive pattern having a half-wave waveform or a sawtooth waveform.

  (3) In the above embodiment, the use of the plunger pump as the reforming water pump 38 has been exemplified. However, the reforming water pump 38 may be configured other than the plunger pump.

  (4) In the ON / OFF control of the above embodiment, whether the flow rate of reforming water during operation of the reforming water pump 38 is higher than a certain flow rate or higher than a certain pressure is monitored. It may be set as a criterion.

  (5) In the above embodiment, the FC system 2 including the fuel cell unit 4 is exemplified, but the present invention may be configured to include only the fuel cell unit.

  As described above, the most preferable embodiment of the present invention has been described. The present invention is not limited to the above description. Various modifications and changes can be made by those skilled in the art based on the gist of the invention described in the claims or disclosed in the embodiments for carrying out the invention. It goes without saying that such modifications and changes are included in the scope of the present invention.

The present invention relates to a fuel cell unit equipped with a reforming water pump for transporting reforming water or an FC system including the fuel cell unit. Since abnormality elimination control for driving with different driving patterns is performed, it is beneficial that, when an abnormality occurs, the abnormality can be resolved by itself, the operation can be normalized, and maintenance for a minor abnormality can be reduced.

2 FC system 4 Fuel cell unit 6 Hot water storage unit 8 Fuel cell stack 10 Fuel treatment device 12 Water tank 14-1, 14-2 Drainer 16 Heat exchanger 18 Control unit 20 Hot water storage tank 22-1, 22-2, 22-3 Water path 24 Fuel treatment section 26 Combustion section 28 Fuel path 30 Selective oxidized air path 32-1, 32-2 Gas path 34 Exhaust path 36 Stack voltmeter 38 Reformed water pump 40-1 Reformed water flow meter 40-2 Fuel Flow meter 40-3 Selective oxidized air flow meter 42-1 Stack inlet pressure gauge 42-2 Reformed water path pressure gauge 42-3 Pressure gauge 42-4 Fuel path pressure gauge 42-5 Air path pressure gauge 44 Temperature sensor 46 Thermoelectric 48 Frame rod 50 Fuel blower 52 Selective oxidation air blower 54 Display unit 56 Error reporting unit 58 Pump drive unit 60 Process Sa 62 ROM
64 NVM
66 RAM
68 Input unit 70 Output unit 72 Display control unit 74 Pump control unit 76 Function 78 Abnormality detection function 80 System stop function 82 Flow rate abnormality determination function 84 Abnormality elimination control function 86 Abnormality elimination control count function 88 Status notification function 90 Abnormality history recording function 92 Display screen 94, 96, 98, 100 Message 102 Abnormal history record data table 104 Data number 106 Day / hour 108 Abnormality detection 110 Control form 112 Number of times 114 Error notification 116 Current status information

Claims (9)

A fuel cell unit comprising a reforming water pump for transporting reforming water,
Flow rate monitoring means for monitoring the flow rate of the reforming water;
The abnormal flow rate of the reforming water is judged from the monitoring output of the flow rate monitoring means, and when the abnormal flow rate occurs in the reforming water, the reforming water pump is driven and stopped at predetermined timings within a unit time. An abnormality elimination control for driving the reforming water pump with a driving pattern different from the normal operation including any one of an intermittent operation, a pump output increasing / decreasing operation, an inversion switching operation of the reforming water flow direction, or two or more is performed. Control means for repeating the abnormality elimination control until the flow rate when the reforming water pump is operating in the drive pattern is equal to or higher than a predetermined flow rate based on the monitoring result of the flow rate monitoring unit ;
A fuel cell unit comprising: The flow rate monitoring means includes one or both of a flow meter for detecting the flow rate of the reformed water flowing in the pipe line by the reformed water pump and a pressure gauge for detecting the pressure in the pipe line. The fuel cell unit according to claim 1, wherein:   3. The fuel cell unit according to claim 1, wherein the control unit counts the number of times of abnormality elimination control and outputs abnormality information when the count reaches a predetermined number. 4. A control program to be executed by a computer mounted on a fuel cell unit including a reforming water pump for transporting reforming water,
Monitoring the flow rate of the reformed water;
Determine the flow rate abnormality of the reforming water from the flow rate monitoring information,
When a flow rate abnormality occurs in the reformed water, the intermittent operation of repeating the drive and stop of the reformed water pump at every predetermined timing within a unit time, the pump output increasing / decreasing operation, the flow rate direction of the reformed water There rows abnormal elimination control for driving the reforming water pump in normal time with different driving pattern include any or more operations reversing switch,
Based on the monitoring result of the flow rate monitoring means, the abnormality elimination control is repeated until the flow rate when the reforming water pump is operating in the drive pattern is equal to or higher than a certain flow rate.
A fuel cell unit control program for causing the computer to execute processing. The control program for a fuel cell unit according to claim 4, wherein the number of times of the abnormality elimination control is counted, and abnormality information is generated when the number of counts reaches a predetermined number. A method for controlling a fuel cell unit including a reforming water pump for transporting reforming water,
Monitoring the flow rate of the reformed water;
Determine the flow rate abnormality of the reforming water from the flow rate monitoring information,
When a flow rate abnormality occurs in the reformed water, the intermittent operation of repeating the drive and stop of the reformed water pump at every predetermined timing within a unit time, the pump output increasing / decreasing operation, the flow rate direction of the reformed water There rows abnormal elimination control for driving the reforming water pump in normal time with different driving pattern include any or more operations inversion switching on the basis of the monitoring result of the flow monitoring means, the reforming water pump wherein A control method for a fuel cell unit, comprising a step of repeating the abnormality elimination control until a flow rate when operating in a drive pattern becomes a predetermined flow rate or more . The method for controlling a fuel cell unit according to claim 6, wherein the abnormality information is generated when the abnormality elimination control is counted and the count reaches a predetermined number. A fuel cell cogeneration system including a fuel cell unit including a reforming water pump for conveying reforming water,
Flow rate monitoring means for monitoring the flow rate of the reforming water;
The abnormal flow rate of the reforming water is judged from the monitoring output of the flow rate monitoring means, and when the abnormal flow rate occurs in the reforming water, the reforming water pump is driven and stopped at predetermined timings within a unit time. An abnormality elimination control for driving the reforming water pump with a driving pattern different from the normal operation including any one of an intermittent operation, a pump output increasing / decreasing operation, an inversion switching operation of the reforming water flow direction, or two or more is performed. Control means for repeating the abnormality elimination control until the flow rate when the reforming water pump is operating in the drive pattern is equal to or higher than a predetermined flow rate based on the monitoring result of the flow rate monitoring unit ;
A fuel cell cogeneration system comprising:   9. The fuel cell cogeneration system according to claim 8, wherein the control means counts the number of times of abnormality elimination control and outputs abnormality information when the count reaches a predetermined number.

Images