JP2011204517A - Fuel cell power generation system, and operation method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten a time necessary for a shipping test and enable to check soundness with sufficient accuracy.SOLUTION: The fuel cell power generation system is provided with a fuel cell body 5, a fuel treatment unit, a cathode blower 8, and a controlling unit 9. The fuel treatment unit is provided with a reformer 2, a high temperature shift converter 3, and a CO selective oxidizer 4 or the like, and reforms a raw fuel to generate hydrogen and supplies the hydrogen to the fuel cell body 5. The cathode blower 8 supplies air to the fuel cell body 5. The controlling unit 9 controls a plurality of controlling amounts of the fuel treatment unit and the cathode blower 8, or the like and carries out a normal operation for the fuel cell body 5 to generate power. Further, the controlling unit 9 carries out a test operation by controlling at least one of these controlling amounts so that it may be in a generation enabled range even if it is out of a normal operation range to put into operation the fuel treatment unit and the cathode blower 8 or the like.

Description

  The present invention relates to a fuel cell power generation system and an operation method thereof.

  Conventionally, a fuel cell is known as a system that directly converts chemical energy of a fuel into electricity (see, for example, Patent Document 1). This fuel cell takes out electricity directly by electrochemically reacting hydrogen as fuel and oxygen as oxidant. A fuel cell has an excellent environmental characteristic that it can take out electric energy with high efficiency and is quiet and does not emit harmful exhaust gas. Until recently, relatively large PAFCs (phosphoric acid type) have been mainly developed, but recently, the development of small PEFCs (solid polymer fuel cells) has become active, and the spread of household fuel cell power generation systems has also increased. The situation is imminent.

  The fuel cell power generation system has a plurality of process quantities. The region where the fuel cell power generation system can generate power exists in a space having these process quantities as variables. If the operating condition changes due to some abnormality and enters a region where power generation is not possible, the fuel cell power generation system cannot maintain power generation.

JP 2009-193936 A

  The normal operating point of the fuel cell power generation system is set, for example, in the vicinity of the center in a region where power generation is possible in a space having a plurality of process quantities as variables. If the operating condition greatly deviates from the normal operating point due to some abnormality and falls outside the region where power generation is possible, power generation cannot be continued. Therefore, assuming that the operating point fluctuates due to temperature fluctuations / temporal fluctuations, the robust securing area including the normal operating point is secured within the operable region. Thereby, in the fuel cell power generation system, power generation can be continued even if the operating conditions slightly vary. As described above, the fuel cell power generation system of the product has characteristics that are robust with respect to the environment and changes over time, so even if a small abnormality occurs in a shipping test or the like, it may not be detected by normal performance measurement.

  In the case of generating power during shipping inspection or the like, in general, power is generated under operating conditions that are assumed to be normal operating points. In this case, even if a minor abnormality occurs and the operating condition is different from the normal operating point, the operation is possible if it is within the power generation possible range. Therefore, even in this state, the test passes. However, if a minor abnormality occurs when the environmental change occurs, for example, when the operating point shifts from the vicinity of the center of the area where power can be generated to the vicinity of the boundary of the area where power can be generated due to the environmental change at the installation location, etc. The operating point shifts outside the region where power generation is possible and power generation becomes impossible, resulting in failure.

  In a reforming fuel cell power generation system that generates power by reforming city gas or LP gas, it is necessary to raise the temperature of the catalyst for hydrogen production to a high temperature. In addition, since it is necessary to settling time in order to stabilize the characteristics, it takes a long time of several hours to measure performance in a shipping test or the like.

  In such a shipping test, it takes a long time, the detection accuracy of the abnormality is low, and a slight abnormality may be missed.

  Therefore, an object of the present invention is to shorten the time required for the shipping test and to check the soundness with high accuracy.

  In order to achieve the above object, the present invention provides a fuel cell power generation system, a fuel cell main body, a fuel processing apparatus that reforms raw fuel to generate hydrogen and supplies the hydrogen to the fuel cell main body, An air supply device for supplying air to the fuel cell main body, a normal operation for controlling a plurality of control amounts of the fuel processing device and the air supply device within a normal operation range to cause the fuel cell main body to generate power, and the control A control device that performs a test operation for controlling the fuel cell body, the fuel processing device, and the air supply device by controlling at least one of the quantities to be outside the normal operation range and within the power generation possible range It is characterized by having.

  The present invention also provides a fuel cell main body, a fuel processing device for reforming raw fuel to generate hydrogen and supplying the hydrogen to the fuel cell main body, and an air supply device for supplying air to the fuel cell main body. A normal operation process in which a plurality of control amounts of the fuel processing device and the air supply device are controlled within a normal operation range to cause the fuel cell body to generate electric power, and the control A test step of operating the fuel cell main body, the fuel processing device, and the air supply device by controlling at least one of the quantities to be outside the normal operation range and within the power generation possible range. It is characterized by.

  According to the present invention, the time required for the shipping test can be shortened and the soundness can be confirmed with high accuracy.

It is a block diagram in one embodiment of a fuel cell power generation system according to the present invention. It is a schematic diagram which shows the driving | running condition of normal driving | operation and test driving | operation in one embodiment of the fuel cell power generation system which concerns on this invention. It is a flowchart of operation | movement of the fuel cell power generation system of one Embodiment of the fuel cell power generation system which concerns on this invention. It is a timing chart at the time of test operation of a fuel cell power generation system, (a) is one embodiment of the fuel cell power generation system concerning the present invention, and (b) shows a comparative example. It is an example of the graph which showed the relationship between the carbon monoxide removal air flow rate and the carbon monoxide remover outlet CO concentration. It is an example of the graph which showed the relationship between the reforming water flow rate and the carbon monoxide remover outlet CO concentration. It is an example of the graph which showed the relationship between the reforming water flow rate and process instability. It is an example of the graph which showed the relationship between carbon monoxide transformer temperature and carbon monoxide remover exit CO concentration. It is an example of the graph which showed the relationship between reformer temperature and a hydrogen utilization factor.

  An embodiment of a fuel cell power generation system according to the present invention will be described with reference to the drawings. This embodiment is merely an example, and the present invention is not limited to this.

  FIG. 1 is a block diagram of an embodiment of a fuel cell power generation system according to the present invention.

  The fuel cell power generation system of the present embodiment includes a fuel processing device, a fuel cell main body 5, an auxiliary machine, and a control device 9. The fuel processing apparatus includes a reformer 2, a carbon monoxide converter 3, and a carbon monoxide remover 4. The reformer 2 generates hydrogen from the raw fuel by a steam reforming reaction. The carbon monoxide converter 3 converts carbon monoxide contained in the hydrogen-rich gas discharged from the reformer 2 into carbon dioxide by causing a shift reaction with water vapor. The carbon monoxide remover 4 receives a small amount of air and oxidizes carbon monoxide remaining in the gas discharged from the carbon monoxide converter 3. The fuel cell main body 5 generates power by consuming hydrogen generated by the fuel processing apparatus.

  As auxiliary equipment, there are a fuel blower 1, a reforming water pump 7, a carbon monoxide removal air blower 6, a cathode blower 8, and the like. The fuel blower 1 supplies fuel to the fuel processing apparatus. The reforming water pump 7 supplies water for reforming steam to the reformer 2. The carbon monoxide removal air blower 6 supplies carbon monoxide removal air to the carbon monoxide remover 4. The cathode blower 8 functions as an air supplier that supplies air to the cathode of the fuel cell 5. The control device 9 performs normal operation and test operation by controlling devices such as a fuel processing device and an auxiliary machine. In addition, the control device 9 is further provided with a function of determining abnormality / normality of the fuel cell system during normal operation and test operation when the process amount is transmitted from the fuel cell main body 5, the fuel processing device, auxiliary equipment, and the like. Have.

FIG. 2 is a schematic diagram showing operating conditions of normal operation and test operation in the present embodiment. In FIG. 2, the horizontal axis and the vertical axis indicate the process quantities X ₁ and X ₂ of the fuel cell power generation system, respectively. In an actual fuel cell power generation system, the process amount is larger than 2, but only two process amounts are schematically shown in FIG.

  The fuel cell power generation system is composed of a plurality of devices, and process amounts such as the temperature of each device and the flow rate of flowing fluid change during operation. These process quantities include quantities that can be controlled directly or indirectly, and the control device 9 controls all or part of the process quantities that can be controlled as control quantities to perform appropriate operation. Control amounts include the flow rate of air supplied to the carbon monoxide remover 4, the amount of reforming water introduced into the reformer 2, the temperature of the carbon monoxide converter 3, the temperature of the reformer 2, and the reforming The raw fuel flow rate introduced into the vessel 2, the cathode air flow rate supplied to the fuel cell main body 5, and the output increase rate of the fuel cell main body 5 are included.

  In order to generate power with the fuel cell power generation system, the control amount needs to be within a predetermined power generation possible range 24. In order to ensure robustness, it is necessary to operate within an operable range 21 narrower than the power generation possible range 24. However, even if the operating conditions are determined so as to simply operate within the operable range 21, it is assumed that the actual operating point fluctuates due to environmental temperature changes, changes with time in the components of the fuel cell power generation system, and the like. .

  Therefore, the normal operation point is set within a normal operation range 22 that is narrower than the operable range 21. That is, the control device 9 causes the fuel cell main body 5 to generate electric power by controlling the control amounts of the devices such as the fuel processing device and the auxiliary machine within the normal operation range 22 during normal operation.

  For example, during normal operation, operation is performed with the control amount set to a normal operation point A within the normal operation range 22. For example, a process amount measurement system may fail due to environmental temperature changes or equipment aging, and the actual operating point of the controlled variable may be C outside the normal operating range 22. Even in such a case, if the normal operation range 22 is set with a margin with respect to the operable range 21, the actual operating point C can be within the operable range 21.

  On the other hand, if a test is performed with the control amount set to the normal operating point A in an inspection such as a pre-shipment inspection of the fuel cell power generation system, a problem has already occurred in, for example, the process amount measurement system, and the actual test Even if the point is the point C within the operable range 21, the operation is possible normally. For this reason, in this case, there is a high possibility that a failure of the fuel cell power generation system cannot be detected.

  Therefore, in the fuel cell power generation system of the present embodiment, the test operation is performed by setting the target value of the control amount to a strict test condition outside the normal operation range 21 and within the power generation possible range 24. If the actual test point is a point D outside the operable range 21 by setting the operating condition at the operating point B in the test operating range 29 close to the boundary of the power generation possible range 24 in the test operation, I cannot generate electricity. As a result, the malfunction of the fuel cell power generation system can be easily detected. Control amounts set to strict test conditions in the test operation are, for example, S / C (steam / carbon ratio) related to an increase in carbon monoxide concentration, carbon monoxide remover air flow, catalyst temperature, and cathode air flow. .

  FIG. 3 is a flowchart of the operation of the fuel cell power generation system of the present embodiment. 4A and 4B are timing charts during a test operation of the fuel cell power generation system. FIG. 4A shows the present embodiment, and FIG. 4B shows a comparative example.

  When a start command is given to the fuel cell power generation system, the control device 9 first determines whether or not the start has been started in the test mode (S1). Whether or not the test mode is selected is designated by a switch (not shown) provided in the fuel cell power generation system, for example.

  If the test mode is not set, the control device 9 causes a device such as a fuel processing device to perform a normal activation sequence (S11). When the normal activation sequence ends, the fuel cell body 5 starts normal power generation (S12).

  In the test mode, first, a device such as a fuel processor is activated (S21). Thereafter, whether or not an abnormality has occurred is confirmed (S22). When it is determined that an abnormality has occurred, the operation of the fuel cell power generation system is stopped. Confirmation of whether or not an abnormality has occurred may be performed continuously during startup.

  If the occurrence of abnormality is not confirmed at the start-up, a CO converter low temperature test is started in which the temperature of the carbon monoxide converter 3 is lower than the normal operation state (S23). The start time of the CO transformer low temperature test corresponds to 0 on the horizontal axis in FIG. In the CO converter low temperature test, the controller 9 controls the carbon monoxide converter 3, auxiliary equipment, etc. so that the temperature of the carbon monoxide converter 3 is, for example, 20 ° C. lower than the temperature under normal operating conditions. To do. When the temperature of the carbon monoxide transformer 3 rises to that temperature, it is confirmed whether or not an abnormality has occurred (S24). Confirmation of the presence or absence of abnormality may be performed continuously during and after the temperature rise of the carbon monoxide transformer 3.

  A CO converter low temperature test is started (S23), and if the carbon monoxide converter 3 reaches a predetermined temperature and no abnormality has occurred, then a high-speed output increase test is performed (S25). In the high-speed output increase test, the control device 9 increases the flow rate of the fuel cell 5 supplied to the reformer 2 to increase the power generation output increase rate of the fuel cell 5 by, for example, 1.5 times the normal operation. To rise.

  Thereafter, whether or not an abnormality has occurred is confirmed (S26). When it is determined that an abnormality has occurred, the operation of the fuel cell power generation system is stopped. Confirmation of whether or not an abnormality has occurred may be continuously performed while the power generation output of the fuel cell 5 is increasing.

  If no abnormality occurs in the high-speed output increase test (S25), a CO remover air increase / decrease test is then performed (S27). In the CO remover air increase / decrease test (S27), the control device 9 controls the carbon monoxide removal air blower 6, and the flow rate of the air supplied to the carbon monoxide remover 4 is increased or decreased by, for example, 10% compared to the normal operation. Let the flow rate. The state in which the amount of air supplied to the carbon monoxide remover 4 is increased by 10% from that during normal operation is continued, for example, for 5 minutes. Further, the state in which the amount of air supplied to the CO remover 4 is reduced by 10% from that during normal operation is continued for, for example, 5 minutes after the end of the state in which the amount is increased by 10%.

  Thereafter, whether or not an abnormality has occurred is confirmed (S28). When it is determined that an abnormality has occurred, the operation of the fuel cell power generation system is stopped. Confirmation of the presence or absence of abnormality may be continuously performed during the CO remover air increase / decrease test.

  FIG. 5 is an example of a graph showing the relationship between the carbon monoxide removal air flow rate and the carbon monoxide remover outlet CO concentration. In FIG. 5, the solid line shows the normal characteristic 11 of the fuel cell power generation system assumed in the design. Moreover, in FIG. 5, the broken line has shown the abnormal characteristic 31 of the actual fuel cell power generation system at the time of a test.

  During normal operation, the air flow rate of the carbon monoxide remover 4 is controlled with the standard point as a target. That is, during normal operation, the air flow rate of the carbon monoxide remover 4 is controlled to be within a predetermined range with the standard point as the center. As a result, if the actual characteristic of the fuel cell power generation system is the normal characteristic 12 assumed in the design, the CO concentration at the outlet of the carbon monoxide remover 4 does not exceed the upper limit 91 of the normal range.

  In the CO remover air increase / decrease test, the test operation is carried out with the carbon monoxide removal air amount reduced by 10% and increased by 10% as an inspection mode. If the characteristic of the fuel cell power generation system is normal characteristic 11, the carbon monoxide remover outlet CO concentration is kept in the normal range with respect to 10% increase / decrease of the carbon monoxide removal air amount, and power generation is continued. As a result, the CO remover air increase / decrease test (S27) is passed.

  On the other hand, if the characteristic of the fuel cell power generation system has changed to the abnormal characteristic 31 for some reason, the operating point is point 41 if the carbon monoxide remover air flow rate is at the standard point. As a result, the CO concentration at the outlet of the carbon monoxide remover does not exceed the upper limit value 91, power generation is possible, and abnormality cannot be detected.

  However, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 31, the operating point becomes the point 51 in the 10% reduction control of the carbon monoxide remover air flow rate. As a result, since the CO concentration at the outlet of the carbon monoxide remover exceeds the upper limit value 91, power generation becomes impossible and an abnormality can be detected.

  As a case where the characteristic of the fuel cell power generation system changes to the abnormal characteristic 31, for example, there is a case where there is a minute leak in the reformed water and the reformed steam is insufficient. It is also considered that abnormal characteristics occur when the temperature of the carbon monoxide transformer is abnormal.

  If no abnormality occurs in the CO remover air increase / decrease test (S27), then a cathode air decrease test is performed (S29). In the cathode air reduction test (S29), the control device 9 controls the cathode blower 8 so that the flow rate of air supplied to the cathode of the fuel cell main body 5 is, for example, 10% lower than that during normal operation. The state of the cathode air flow rate lower than that in the normal operation is continued for 1 minute, for example.

  Thereafter, whether or not an abnormality has occurred is confirmed (S30). When it is determined that an abnormality has occurred, the operation of the fuel cell power generation system is stopped. Confirmation of the occurrence of abnormality may be performed continuously during the cathode air reduction test.

  If no abnormality occurs in the cathode air reduction test (S29), then a reforming water flow rate reduction test is performed (S31). In the reforming water flow rate reduction test (S31), the control device 9 controls the reforming water pump 7 to reduce the flow rate of the reforming water supplied to the reformer 2 by, for example, 5% from that during normal operation. Flow rate. The state in which the amount of the reforming water supplied to the reformer 2 is reduced by 5% from the normal operation is continued for 10 minutes, for example.

  Thereafter, whether or not an abnormality has occurred is confirmed (S32). When it is determined that an abnormality has occurred, the operation of the fuel cell power generation system is stopped. Confirmation of the occurrence of abnormality may be continuously performed during the reforming water flow reduction test.

  Further, the reforming water flow rate increase test may be performed before or after the reforming water flow rate decrease test (S31). In the reforming water flow rate increase test, the reforming water pump 7 is controlled so that the flow rate of the reforming water supplied to the reformer 2 is increased by, for example, 10% from that during normal operation. The state in which the amount of the reforming water supplied to the reformer 2 is increased by 10% from the normal operation is continued for 10 minutes, for example.

  FIG. 6 is an example of a graph showing the relationship between the reforming water flow rate and the carbon monoxide remover outlet CO concentration. FIG. 7 is an example of a graph showing the relationship between the reforming water flow rate and the process instability. 6 and 7, the solid lines indicate the normal characteristics 12 and 13 of the fuel cell power generation system assumed in the design. 6 and 7, broken lines indicate the abnormal characteristics 32 and 33 of the actual fuel cell power generation system during the test.

  During normal operation, the flow rate of reforming water supplied to the reformer 2 by the reforming steam pump 7 is controlled with a standard point as a target. That is, during normal operation, the reforming water flow rate of the reformer 2 is controlled so as to be within a predetermined range centering on the standard point. As a result, if the characteristic of the fuel cell power generation system is the normal characteristic 12 assumed in the design, the CO concentration at the outlet of the carbon monoxide transformer 3 does not exceed the upper limit 92. Further, if the actual characteristic of the fuel cell power generation system is the normal characteristic 13 assumed in the design, the process instability does not exceed the upper limit value 93.

  In the reforming water flow rate reduction test and the reforming water flow rate increase test, a test operation in which the reforming water flow rate is decreased by 5% and increased by 10% is performed as an inspection mode. For example, if the actual characteristic of the fuel cell power generation system is the normal characteristic 12, the operating points when the reforming water flow rate is reduced by 5% are points 42 and 43. In other words, if the actual characteristic of the fuel cell power generation system is the normal characteristic 12, the CO concentration at the outlet of the carbon monoxide converter is kept in the normal range with respect to the 5% decrease and 10% increase in the reforming water flow rate. Will continue. If the actual characteristic of the fuel cell power generation system is the normal characteristic 13, the process instability is maintained in the normal range, and power generation is continued. As a result, the reforming water flow rate reduction test (S31) is passed.

  On the other hand, if the characteristic of the fuel cell power generation system has changed to the abnormal characteristic 32 shown by the broken line in FIG. 6 for some reason, the operating point is point 42 if the reforming water flow rate is at the standard point. As a result, the CO concentration at the outlet of the carbon monoxide remover does not exceed the upper limit value 92, power generation is possible, and abnormality cannot be detected.

  However, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 32, the operating point becomes the point 52 in the 5% reduction control of the reforming water flow rate. As a result, in the 5% reduction control of the reforming water flow rate, the CO concentration at the outlet of the carbon monoxide remover exceeds the upper limit 92, so that power generation becomes impossible and an abnormality can be detected.

  As a case where the characteristic of the fuel cell power generation system changes to the abnormal characteristic 32, for example, there is a case where there is a minute leak in the reformed water and the reformed steam is insufficient. Further, it is considered that abnormal characteristics are obtained even when the temperature of the carbon monoxide transformer 3 is abnormal.

  If the characteristic of the fuel cell power generation system has changed to an abnormal characteristic 33 shown by a broken line in FIG. 7 for some reason, the operating point is point 43 if the reforming water flow rate is at the standard point. As a result, the process instability does not exceed the upper limit value 93, power generation is possible, and abnormality cannot be detected.

  However, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 33, the operating point becomes the point 53 in the 10% increase control of the reforming water flow rate. As a result, since the process instability exceeds the upper limit value 93, power generation becomes impossible and an abnormality can be detected. As a case where the characteristic of the fuel cell power generation system changes to the abnormal characteristic 33, for example, a case where the amount of burner air in the reformer 2 is insufficient is given.

  When these tests are finished, the CO transformer low temperature test is finished (S33). If no abnormality occurs in the fuel cell power generation system until the end of the low temperature test of the CO transformer, the determination is normal. If an abnormality occurs in the fuel cell power generation system by the end of the CO transformer low temperature test, an abnormality determination is made, and the test is terminated when the abnormality occurs.

  FIG. 8 is an example of a graph showing the relationship between the carbon monoxide transformer temperature and the carbon monoxide outlet CO concentration. In FIG. 8, the solid line indicates the normal characteristic 14 of the fuel cell power generation system assumed in the design. Moreover, in FIG. 8, the broken line has shown the abnormal characteristic 34 of the actual fuel cell power generation system at the time of a test.

  During normal operation, the temperature of the carbon monoxide transformer 3 is controlled with the standard point as a target. That is, during normal operation, the temperature of the carbon monoxide transformer 3 is controlled to be within a predetermined range with the standard point as the center. As a result, if the actual characteristic of the fuel cell power generation system is the normal characteristic 14 assumed in the design, the CO concentration at the outlet of the carbon monoxide transformer 3 does not exceed the upper limit 94 of the normal range.

  In the CO transformer low temperature test, a test operation in which the set temperature of the carbon monoxide transformer 3 is lowered by 20 ° C. is performed as an inspection mode. For example, if the characteristic of the fuel cell power generation system is the normal characteristic 14, the carbon monoxide transformer outlet CO concentration is kept in the normal range and the power generation is continued with respect to a 20 ° C. decrease in the carbon monoxide transformer set temperature. . As a result, the CO transformer low temperature test passes.

  On the other hand, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 34 for some reason, the operating point is a point 44 if the carbon monoxide transformer set temperature is at the standard point. As a result, the carbon monoxide transformer outlet CO concentration does not exceed the upper limit 94, power generation is possible, and abnormality cannot be detected.

  However, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 34, the operating point becomes the point 54 in the control in which the carbon monoxide transformer set temperature is lowered by 20 ° C. As a result, since the carbon monoxide transformer outlet CO concentration exceeds the upper limit 94, power generation becomes impossible and an abnormality can be detected. As a case where the characteristic of the fuel cell power generation system changes to the abnormal characteristic 34, for example, there is a case where there is a minute leak in the reformed water and the reformed steam is insufficient.

  Further, while the CO transformer low temperature test is being performed, a reformer temperature 10 ° C. low test may be further performed. In the reformer temperature 10 ° C. low test, a test operation in which the set temperature of the reformer 2 is lowered by 10 ° C. is performed as an inspection mode.

  FIG. 9 is an example of a graph showing the relationship between the reformer temperature and the hydrogen utilization rate. In FIG. 9, the solid line indicates the normal characteristic 15 of the fuel cell power generation system assumed in the design. Moreover, in FIG. 9, the broken line has shown the abnormal characteristic 35 of the actual fuel cell power generation system at the time of a test.

  During normal operation, the temperature of the reformer 2 is controlled with the standard point as a target. That is, during normal operation, the temperature of the reformer 2 is controlled to be within a predetermined range with the standard point as the center. As a result, if the actual characteristic of the fuel cell power generation system is the normal characteristic 15 assumed in the design, the hydrogen utilization rate does not exceed the upper limit value 95 of the normal range.

  In the reformer temperature 10 ° C. low test, a test operation in which the set temperature of the reformer 2 is lowered by 10 ° C. is performed as an inspection mode. If the characteristic of the fuel cell power generation system is the normal characteristic 15, the hydrogen utilization rate is maintained in the normal range with respect to a 10 ° C. decrease in the reformer set temperature, and power generation is continued. As a result, the reformer temperature 10 ° C. low test passes.

  On the other hand, if the characteristic of the fuel cell power generation system has changed to the abnormal characteristic 35 for some reason, the operating point is point 45 if the reformer set temperature is at the standard point. As a result, the hydrogen utilization rate does not exceed the upper limit value 95, power generation is possible, and abnormality cannot be detected.

  However, when the characteristic of the fuel cell power generation system is changed to the abnormal characteristic 35, the operating point becomes a point 55 in the case where the reformer set temperature is controlled to be 10 ° C. low. As a result, since the hydrogen utilization rate exceeds the upper limit value 95, power generation becomes impossible and an abnormality can be detected. As a case where the characteristic of the fuel cell power generation system changes to the abnormal characteristic 35, for example, there is a case where there is a minute leak in the reformed water and the reformed steam is insufficient.

  Thus, in the fuel cell power generation system of the present embodiment, during normal operation, operation is performed in a normal operation range narrower than the operation range in which power generation is possible in order to ensure safety and cope with environmental changes. On the other hand, in the shipping test, a test is performed under severe conditions that deviate from the normal operation range and are close to the boundary of the operation range in which power generation is possible. For this reason, there is a high possibility that a defect that cannot be detected by the test in the normal operation range can be detected. That is, the possibility of detecting an abnormal state of the fuel cell power generation system can be increased.

  On the other hand, when the shipping test is performed while stabilizing the characteristics of the fuel cell power generation system, for example, as shown in FIG. 4B, a longer time is required as compared with the present embodiment. First, in order to raise the temperature of the carbon monoxide transformer 3 to the standard set temperature, it takes a longer time than when raising the temperature to, for example, 20 ° C. lower than the standard set temperature. For this reason, the start of power generation in the fuel cell power generation system is delayed compared to the present embodiment.

  Moreover, in this Embodiment, the electric power generation output in the fuel cell main body 5 is raised at high speed, and various tests are performed without waiting for settling. However, when carrying out a shipping test while stabilizing the characteristics of the fuel cell power generation system, it takes a long time to slowly increase the power generation output to the rated output, and a longer time to settling.

  As described above, in this embodiment, since the test is performed under severe conditions, it is not necessary to measure the static characteristics after setting the fuel cell power generation system, and to detect an abnormality due to a slight change in the performance. . Therefore, the time required for the shipping test can be shortened.

  Furthermore, by causing the control device to automatically perform such various test operations, it is possible to reduce the time required for the shipping test and to save labor for the shipping test. In addition, even after shipping and installation, for example, the function can be automatically confirmed when the repair is completed.

  Thus, according to the present embodiment, it is possible to shorten the time required for the shipping test and to check the soundness with high accuracy. As a result, a low-cost and highly reliable fuel cell power generation system can be provided.

  As with a general fuel cell power generation system, the fuel cell power generation system according to the present embodiment is designed so that an unsafe situation does not occur even if a double failure occurs. By designing so that safety is not impaired even if a double failure occurs in this way, it will not be an unsafe situation even if severe test operation is performed as in this embodiment. Absent.

  Further, this embodiment is merely an example, and the present invention is not limited to this. For example, in the above-described embodiment, the soundness is confirmed by whether or not a failure stop occurs during the power generation test, but the soundness may be confirmed by other methods. For example, the component of the gas at the outlet of the carbon monoxide transformer can be continuously analyzed, and if the carbon monoxide concentration at the outlet exceeds 0.6%, an abnormality can be made. Moreover, the component of the gas at the outlet of the carbon monoxide remover is analyzed, and if the concentration of carbon monoxide at the outlet exceeds 100 ppm, an abnormality can be determined. By analyzing the various process amounts of the fuel cell power generation system in this way, it is possible to detect an abnormality with higher accuracy. It is also possible to change the amount of combustion air and combustion fuel when the burner of the reformer 2 is ignited, to grasp the success rate of ignition, and to check whether each is properly controlled.

DESCRIPTION OF SYMBOLS 1 ... Fuel blower, 2 ... Reformer, 3 ... Carbon monoxide converter, 4 ... Carbon monoxide remover, 5 ... Fuel cell main body, 6 ... Carbon monoxide removal air blower, 7 ... Reformed water pump, 8 DESCRIPTION OF SYMBOLS ... Cathode blower, 9 ... Control apparatus, 21 ... Operation possible range, 22 ... Normal operation range, 24 ... Electric power generation possible range, 29 ... Test operation range, 11-15 ... Normal characteristic, 31-35 ... Abnormal characteristic

Claims (15)

A fuel cell body;
A fuel processor for reforming raw fuel to produce hydrogen and supplying the hydrogen to the fuel cell body;
An air supply device for supplying air to the fuel cell body;
A normal operation in which a plurality of control amounts of the fuel processing device and the air supply device are controlled within a normal operation range to cause the fuel cell body to generate power, and at least one of the control amounts is outside the normal operation range. A control device that performs a test operation that controls the fuel cell body, the fuel processing device, and the air supply device to be controlled to be within a power generation possible range;
A fuel cell power generation system comprising: The fuel processor is a reformer that generates hydrogen from a raw fuel by a steam reforming reaction, and carbon monoxide conversion in which carbon monoxide in a gas discharged from the reformer is reacted with steam to convert it into carbon dioxide. And a carbon monoxide remover that oxidizes carbon monoxide in a gas introduced from the carbon monoxide converter with air introduced therein,
The control amount includes the flow rate of air supplied to the carbon monoxide remover, the amount of reforming water introduced into the reformer, the temperature of the carbon monoxide converter, the temperature of the reformer, and the reforming. 2. The fuel cell power generation system according to claim 1, comprising a raw fuel flow rate introduced into a vessel, a cathode air flow rate supplied to the fuel cell main body, and an output increase rate of the fuel cell main body.   The test operation includes a test for increasing the air flow rate by a predetermined amount from a maximum value of the normal operation range and a test for decreasing the air flow rate by a predetermined amount from a minimum value of the normal operation range. 2. The fuel cell power generation system according to 2.   The test operation includes a test for increasing the introduction amount of the reforming water by a predetermined amount from a maximum value of the normal operation range and a test for decreasing the air flow rate by a predetermined amount from a minimum value of the normal operation range. The fuel cell power generation system according to claim 2 or 3.   The fuel according to any one of claims 2 to 4, wherein the test operation includes a test in which the temperature of the carbon monoxide transformer is lower than a minimum value of the normal operation range by a predetermined value. Battery power generation system.   6. The fuel cell power generation according to claim 2, wherein the test operation includes a test in which the temperature of the reformer is lower than a minimum value of the normal operation range by a predetermined value. system.   The fuel cell power generation system according to any one of claims 2 to 6, wherein the test operation includes a test in which the raw fuel flow rate is reduced by a predetermined amount from a minimum value of the normal operation range.   The fuel cell power generation system according to any one of claims 2 to 7, wherein the test operation includes a test in which the cathode air flow rate is reduced by a predetermined amount from a minimum value of the normal operation range.   The fuel cell power generation system according to any one of claims 2 to 8, wherein the test operation includes a test in which the output increase speed is set to a predetermined coefficient multiple of the maximum value of the normal operation range. .   The reformer includes a burner, and further includes air supply means for supplying air to the burner and fuel supply means for supplying fuel to the burner, and the control amount includes a burner air flow rate and a burner fuel flow rate, The test operation includes a test for controlling at least one of the burner air flow rate and the burner fuel flow rate to be outside the normal operation range and within the power generation possible range. 10. The fuel cell power generation system according to any one of 9 above.   2. The control device according to claim 1, further comprising a function of determining whether an abnormality has occurred in any of the fuel cell body, the fuel processing device, and the air supply device during the test operation. Item 11. The fuel cell power generation system according to any one of Items 10.   The control device is based on any one of the abnormality in the generated voltage of the fuel cell main body and the temperature abnormality in any part of the fuel cell main body, the fuel processing device, and the air supply device, 12. The fuel cell power generation system according to claim 11, wherein it is determined whether or not an abnormality has occurred in either the fuel processing device or the air supply device.   The control device is connected to any one of the fuel cell main body, the fuel processing device, and the air supply device based on an abnormality in the carbon monoxide concentration at the outlet of either the carbon monoxide transformer or the carbon monoxide remover. The fuel cell power generation system according to claim 11, wherein it is determined whether or not an abnormality has occurred.   The control device further has a function of determining whether the fuel cell main body, the fuel processing device, and the air supply device are in process and determining whether the test operation is abnormal or normal. The fuel cell power generation system according to any one of claims 1 to 13. A fuel cell comprising: a fuel cell main body; a fuel processing device for reforming raw fuel to generate hydrogen and supplying the hydrogen to the fuel cell main body; and an air supply device for supplying air to the fuel cell main body In the operation method of the power generation system,
A normal operation process in which a plurality of control amounts of the fuel processing device and the air supply device are controlled within a normal operation range to cause the fuel cell body to generate electric power;
A test step of operating the fuel cell body, the fuel processing device, and the air supply device by controlling at least one of the control amounts to be outside the normal operation range and within a power generation possible range;
A method for operating a fuel cell power generation system, comprising:

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