POWER CONTROL METHOD, POWER CONTROL DEVICE, AND POWER SUPPLY SYSTEM

Abstract

The power control method disclosed herein includes the steps of: when supplying power to a power load of a power consumer from a distributed power source system including a fuel cell device and a power storage device, controlling the power generation power of the fuel cell device to a planned value of the power generation power of the fuel cell device; and, when performing the control, performing a first correction to decrease the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is greater than an upper limit value less than 100%, or performing a second correction to increase the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is less than a lower limit value greater than 0%.

Description

[Technical field]

[0001] The present disclosure relates to a power control method, a power control device, and a power supply system. [Background technology]

[0002] Various proposals have been made for power control of a power supply system. As an example, Patent Document 1 describes a method for determining the output of a fuel cell according to the amount of electricity stored in a storage battery. Specifically, it discloses a control method for lowering the output of the fuel cell when the amount of electricity stored in the storage battery is large, and for increasing the output of the fuel cell when the amount of electricity stored in the storage battery is small. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2015 / 162940 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide, as an example, a power control method, a power control device, and a power supply system that can reduce the possibility that a power storage device will become fully charged or completely discharged compared to conventional methods. [Means for solving the problem]

[0005] In order to solve the above problem, a power control method of one aspect of the present disclosure includes the steps of: when supplying power to a power load of a power consumer from a distributed power source system including a fuel cell device and a power storage device, controlling the power generation power of the fuel cell device to a planned value of the power generation power of the fuel cell device; and, when performing the control, performing a first correction to decrease the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is greater than an upper limit value less than 100%, or performing a second correction to increase the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is less than a lower limit value greater than 0%.

[0006] One aspect of the present disclosure is a power control device for a distributed power supply system including a fuel cell device and a power storage device, the power control device comprising: a memory device that stores a planned value of the power generation power of the fuel cell device; and a controller that controls the power generation power of the fuel cell device to the planned value of the power generation power of the fuel cell device when power is supplied from the distributed power supply system to a power load of a power consumer, and when the controller is performing the control, when the charging rate of the power storage device after a predetermined time estimated based on the planned value is greater than an upper limit value that is less than 100%, the controller performs a first correction that decreases the planned value, or when the charging rate of the power storage device after a predetermined time estimated based on the planned value is less than a lower limit value that is greater than 0%, the controller performs a second correction that increases the planned value.

[0007] A power supply system according to one aspect of the present disclosure includes a fuel cell device, a power storage device, and the above-described power control device. Effect of the Invention

[0008] The power control method, power control device, and power supply system according to one embodiment of the present disclosure have the effect of reducing the possibility that the power storage device will be in a fully charged state or a completely discharged state more than in the past. [Brief description of the drawings]

[0009] [Figure 1]FIG. 1 is a diagram illustrating an example of a power supply system according to the first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating an example of a distributed power supply system included in the power supply system of the first embodiment. [Diagram 3] FIG. 3 is a diagram illustrating an example of the power control device according to the first embodiment. [Figure 4A] FIG. 4A is a flowchart showing an example of the operation (power control method) of the power control device of the first embodiment. [Figure 4B] FIG. 4B is a flowchart showing an example of the operation (power control method) of the power control device of the first embodiment. [Diagram 5] FIG. 5 is a diagram for explaining an example of the operation (power control method) of the power control device of the first embodiment. [Figure 6] FIG. 6 is a diagram for explaining an example of the operation of the power control device (power control method) in the first example of the first embodiment. [Figure 7] FIG. 7 is a diagram for explaining an example of the operation of the power control device (power control method) in the second example of the first embodiment. [Figure 8] FIG. 8 is a diagram for explaining an example of the operation of the power control device (power control method) in the third example of the first embodiment. [Figure 9] FIG. 9 is a diagram illustrating an example of a distributed power supply system included in a power supply system according to a fourth example of the first embodiment. [Figure 10] FIG. 10 is a diagram illustrating an example of a power supply system according to the second embodiment. [Figure 11A] FIG. 11A is a flowchart showing an example of the operation (power control method) of the power control device of the second embodiment. [Figure 11B] FIG. 11B is a flowchart showing an example of the operation (power control method) of the power control device of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In Patent Document 1, a real-time measured value is used as the amount of electricity stored in the storage battery when determining the output of the fuel cell. For this reason, the invention described in Patent Document 1 does not describe a method for determining the output of the fuel cell that takes into account a future estimated value of the amount of electricity stored in the storage battery, and as a result, the storage battery may become fully charged or completely discharged. When the storage battery becomes fully charged, reverse power flow from the distributed power source to the power grid is likely to occur. Conversely, when the storage battery becomes fully discharged, power purchase from the power grid is likely to occur.

[0011] Therefore, the power control method of the first aspect of the present disclosure comprises the steps of controlling the power generation power of the fuel cell device to a planned value of the power generation power of the fuel cell device when supplying power to a power load of a power consumer from a distributed power source system including a fuel cell device and a power storage device, and performing, while performing the control, a first correction to decrease the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value of the power generation power of the fuel cell device is greater than an upper limit value less than 100%, or a second correction to increase the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value of the power generation power of the fuel cell device is less than a lower limit value greater than 0%.

[0012] According to the above, the power control method of the present aspect can reduce the possibility that the power storage device will be in a fully charged state or a completely discharged state, compared to conventional methods.

[0013] Specifically, when the power control method of this aspect is executing the above control, if the charging rate of the power storage device after a predetermined time, which is estimated based on the planned value of the power generation power of the fuel cell device, is higher than an upper limit value which is lower than 100%, a first correction is made to decrease this planned value, thereby appropriately reducing the possibility that the power storage device will be in a fully charged state, compared to the case where the first correction is not made. When the power storage device is in a fully charged state, reverse power flow from the distributed power system to the power grid is likely to occur, but the power control method of this aspect can suppress the occurrence of such reverse power flow by the first correction.

[0014] Furthermore, when the power control method of this aspect is executing the above control, if the charge rate of the power storage device after a predetermined time estimated based on the planned value of the power generation power of the fuel cell device is smaller than a lower limit value larger than 0%, a second correction is made to increase this planned value, thereby appropriately reducing the possibility that the power storage device will enter a fully discharged state compared to a case where such a second correction is not made. When the power storage device enters a fully discharged state, power purchase from the power grid becomes more likely, but the power control method of this aspect can suppress such power purchase by the second correction.

[0015] A second aspect of the power control method of the present disclosure may be such that, in the power control method of the first aspect, a first specified period during which the first correction or the second correction is maintained is shorter than a second specified period during which the planned value of the power generation power of the fuel cell device is maintained.

[0016] A power control method of a third aspect of the present disclosure, in the power control method of the first or second aspect, may not require the above-mentioned first correction or second correction to be performed in a third specified period before the planned value of the power generation power of the fuel cell device is switched or in a fourth specified period after the planned value is switched.

[0017] When the first correction or the second correction is performed in a specified period before and after the timing when the planned value of the power generation power of the fuel cell device is switched, the period during which the output of the fuel cell device changes based on the planned value of the power generation power of the fuel cell device and the period during which the output of the fuel cell device changes based on the first correction or the second correction may overlap.

[0018] In other words, it takes a certain amount of time for the output of the fuel cell device to reach a desired target value, and if the first or second correction is performed immediately before the planned value of the power generation of the fuel cell device is switched, there is a possibility that while the output of the fuel cell device is changing based on the first or second correction, a change in the output of the fuel cell device will be instructed based on the planned value of the power generation of the fuel cell device, which may make it difficult to control the output of the fuel cell device according to the planned power generation of the fuel cell device.

[0019] Furthermore, if the first or second correction is executed immediately after the planned value of the power generation of the fuel cell device is changed, a change in the output of the fuel cell device may be instructed based on the first or second correction while the output of the fuel cell device is changing based on the planned value of the power generation of the fuel cell device, which may make it difficult to control the output of the fuel cell device in accordance with the correction of the power generation of the fuel cell device.

[0020] However, the power control method of the present embodiment prohibits the execution of the first correction or the second correction during the third specified period before the planned value of the power generation power of the fuel cell device is switched or during the fourth specified period after the planned value is switched, making it easier to appropriately control the output of the fuel cell device compared to a case in which the execution of the first correction and the second correction are not prohibited.

[0021] A fourth aspect of the power control method of the present disclosure is such that, in the power control method of the third aspect, the third specified period or the fourth specified period may be longer than or equal to the time required for the output of the fuel cell device to reach the switched planned value after the planned value of the power generation power of the fuel cell device is switched.

[0022] As described above, the power control method of this embodiment sets the third specified period or the fourth specified period to be equal to or longer than the time required for the output of the fuel cell device to reach the switched planned value after switching the planned value of the power generation power of the fuel cell device, thereby appropriately reducing the possibility of an overlap between the period in which the output of the fuel cell device changes based on the planned value of the power generation power of the fuel cell device and the period in which the output of the fuel cell device changes based on the first correction or the second correction, compared to when the third specified period and the fourth specified period are shorter than the required time.

[0023] A fifth aspect of the power control method of the present disclosure is the power control method of the first aspect, in which the first correction or the second correction may not be executed for a fifth specified period after starting to execute the first correction or the second correction.

[0024] It takes a certain amount of time for the output of the fuel cell device to reach a desired target value, and if the first or second correction is executed again immediately after the execution of the first or second correction, while the output of the fuel cell device is changing based on the former correction, the output of the fuel cell device may be commanded to change based on the latter correction, which may make it difficult to control the output of the fuel cell device in accordance with the correction of the generated power of the fuel cell device.

[0025] However, in the power control method of the present embodiment, by prohibiting re-execution of the first correction or the second correction for a fifth specified period after starting the execution of the first correction or the second correction, it becomes easier to appropriately control the output of the fuel cell device compared to a case in which re-execution of the first correction and the second correction is not prohibited.

[0026] A sixth aspect of the power control method of the present disclosure is the power control method of the first aspect, wherein the distributed power supply system further includes a solar power generation device, and when executing the above control, the charging rate of the power storage device after a predetermined time period may be estimated from the difference between an actual value of the power demand of the power consumer in the immediately preceding sixth predetermined period and the sum of the actual value of the solar power generation device and the planned value of the power generation power of the fuel cell device.

[0027] According to the above, in the power control method of this embodiment, the difference between the most recent actual value of the power demand of the power consumer and the sum of the most recent actual value of the solar power generation device and the planned value of the power generation power of the fuel cell device corresponds to the charging power or discharging power of the power storage device, and therefore the charging rate of the power storage device after a predetermined time can be appropriately estimated based on this difference.

[0028] A seventh aspect of the present disclosure is a power control device for a distributed power supply system including a fuel cell device and a power storage device, comprising: a memory for storing a planned value of the power generation of the fuel cell device; and a controller for controlling the power generation of the fuel cell device to the planned value of the power generation of the fuel cell device when power is supplied from the distributed power supply system to a power load of a power consumer, wherein, when performing the above control, the controller performs a first correction to decrease the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is greater than an upper limit value that is less than 100%, or a second correction to increase the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is less than a lower limit value that is greater than 0%.

[0029] With this configuration, the power control device of this aspect can reduce the possibility that the power storage device will be in a fully charged state or a completely discharged state more than ever before. Note that the details of the effects and advantages achieved by the power control device of this aspect are similar to those achieved by the power control method of the first aspect, and therefore will not be described here.

[0030] A power supply system according to an eighth aspect of the present disclosure includes a fuel cell device, a power storage device, and the power control device according to the seventh aspect.

[0031] With this configuration, the power supply system of this aspect can reduce the possibility that the power storage device will be in a fully charged state or a completely discharged state more than ever before. Note that the details of the effects and advantages of the power supply system of this aspect are similar to those of the power control method of the first aspect, and therefore will not be described here.

[0032] Hereinafter, specific examples of the above-mentioned aspects of the present disclosure will be described with reference to the accompanying drawings. The specific examples described below are all examples of the above-mentioned aspects of the present disclosure. Therefore, the shapes, numerical values, components, arrangement positions and connection forms of the components shown below do not limit the scope of the claims unless otherwise stated in the claims.

[0033] In addition, among the components described below, components that are not described in the independent claims showing the highest concept of the present disclosure are described as optional components. In addition, in the drawings, the description of components with the same reference numerals may be omitted. The drawings show each component diagrammatically to facilitate understanding, and the shapes and dimensional ratios may not be displayed accurately.

[0034] Furthermore, in the operation of the apparatus, the order of steps may be changed or known steps may be added as necessary.

[0035] (First embodiment) [Device configuration] Fig. 1 is a diagram illustrating an example of a power supply system according to a first embodiment. Fig. 2 is a diagram illustrating an example of a distributed power supply system provided in the power supply system according to the first embodiment. Fig. 3 is a diagram illustrating an example of a power control device according to the first embodiment.

[0036] As shown in Fig. 1, a power supply system 10 of this embodiment includes a power control device 20 and a distributed power supply system 30. Here, as shown in Fig. 2, the distributed power supply system 30 includes a fuel cell device 31 and a power storage device 32. This power supply system 10 may be, for example, a system that supplies large amounts of power to a power grid. In this case, the fuel cell device 31 and the power storage device 32 each include a fuel cell unit group consisting of a plurality of fuel cell units including a fuel cell stack, and a storage battery unit group consisting of a plurality of storage battery units, respectively. A detailed configuration of such a power supply system 10 will be described in the second embodiment.

[0037] The fuel cell device 31 generates power by utilizing hydrogen supplied from a hydrogen supply source (not shown) under the control of the power control device 20. The power generated by the fuel cell device 31 is supplied to a power load 40, a power system, or a power storage device 32. A well-known device can be used as the fuel cell device 31. An example of the hydrogen supply source is, but is not limited to, a hydrogen storage tank.

[0038] The power storage device 32 is a device that stores the power generated by the fuel cell device 31 or the power received from the power grid under the control of the power control device 20. The power stored in the power storage device 32 may be discharged to the power load 40 of the power consumer or to the power grid under the control of the power control device 20. Examples of power consumers that receive the service of power supply generated by the power supply system 10 include, but are not limited to, factories, stores, and general households.

[0039] The power storage device 32 can transmit, at an appropriate timing, a state of charge (SOC) indicating the remaining amount of power (amount of charge) stored in the power storage device 32 to the power control device 20. An example of the power storage device 32 can be, but is not limited to, a secondary battery.

[0040] As shown in FIG. 3, the power control device 20 includes a storage unit 21 and a controller 22.

[0041] The memory 21 stores a planned value FC of the power generation power FC of the fuel cell device 31. main For example, the power control device 20 receives a planned value FC main The power generation plan for the power generation system may be received.

[0042] The users of the terminal or server include direct or indirect users of the power control device 20. A direct user of the power control device 20 is, for example, an administrator of the power control device 20. An indirect user of the power control device 20 can be, for example, an owner of the power supply system 10. Such an owner may be a power consumer who receives the service of supplying power generated by the power supply system 10, or a power generation business operator who supplies power to power consumers using the power supply system 10.

[0043] When the distributed power supply system 30 supplies power to the power load 40 of the power consumer, the controller 22 sets a planned value FC of the power generation power FC of the fuel cell device 31. mainThe controller 22 controls the generated power FC of the fuel cell device 31 in accordance with the planned value FC main The state of charge (SOC) of the power storage device 32 after a predetermined time is estimated based on lator Upper limit SOC is less than 100% upper When it is greater than , the planned value FC main The first correction, which reduces the planned value FC main The state of charge (SOC) of the power storage device 32 after a predetermined time is estimated based on lator Lower limit SOC is greater than 0% lower When it is smaller than the planned value FC main A second correction is performed increasing

[0044] "Upper limit SOC upper " and "Lower SOC lower " can be set to an appropriate value based on the configuration of the power supply system 10, etc. upper For example, the lower limit SOC is about 90%. lower For example, it can be said that the rate is about 10%.

[0045] The "predetermined time" can be set to an appropriate period based on the configuration of the power supply system 10. An example of the "predetermined time" is about 60 minutes.

[0046] Specific examples of the "first correction" and the "second correction" will be described in the second embodiment.

[0047] The controller 22 may have any control function, and includes an arithmetic processing unit (not shown) and a storage unit (not shown) that stores a control program. The arithmetic processing unit reads out and executes the control program stored in the storage unit, thereby performing predetermined control in the controller 22. An example of the arithmetic processing unit is a microprocessor. An example of the storage unit is a memory.

[0048] [Operation] Figures 4A and 4B are flowcharts showing an example of the operation (power control method) of the power control device of the first embodiment. Figure 5 is a diagram for explaining an example of the operation (power control method) of the power control device of the first embodiment.

[0049] The following operations may be performed, for example, by the calculation processing unit of the controller 22 reading out a control program from the storage unit of the controller 22. However, it is not essential that the following operations are performed by the controller 22. An operator may perform some of the operations. In the following example, a case where the operations are controlled by the controller 22 will be described.

[0050] The operation of the power control device 20 in FIG. 4A will now be described.

[0051] First, the planned value FC of the generated power FC of the fuel cell device 31 is transmitted via the communication network. main is received.

[0052] When the distributed power supply system 30 supplies power to the power load 40 of the power consumer, as shown in FIG. 4A, in step S1, the planned value FC of the power generation power FC of the fuel cell device 31 is set to main An operation for controlling the generated power FC of the fuel cell device 31 is then performed.

[0053] Next, while the control of step S1 is being executed, in step S2A, the planned value FC of the generated power FC of the fuel cell device 31 is set to main The state of charge (SOC) of the power storage device 32 after a predetermined time is estimated based on lator However, the upper limit SOC is less than 100%. upper It is determined whether it is greater than

[0054] Here, the "predetermined time" may be, for example, about 60 minutes, but is not limited to this. upper " may be, for example, about 90%, but is not limited to this.

[0055] SOC of the power storage device 32 latorUpper limit SOC is less than 100% upper If it is greater than the planned value FC main Specifically, the correction value FC of the generated power FC of the fuel cell device 31 is reduced by sub is calculated, and the planned value FC of the generated power FC of the fuel cell device 31 is main In other words, the planned value FC main Correction value FC sub The generated power FC of the fuel cell device 31 is obtained by adding these values ​​together (FC=FC main +FC sub The above amendment is an example of the "first amendment" of the present disclosure.

[0056] For example, as shown in FIG. 5, the planned value FC of the generated power FC of the fuel cell device 31 main At 300 kW, at time [0:20], the charging rate SOC of the storage device 32 lator is the upper limit SOC upper When SOC is greater than lator >SOC upper ), the correction value FC of the generated power FC of the fuel cell device 31 sub However, when the calculated SOC is -20kW, the generated power FC of the fuel cell device 31 is corrected to 280kW (FC=300kW-20kW). lator But SOC upper It is calculated as the value below.

[0057] In addition, the planned value FC of the power generation power FC of the fuel cell device 31 main At 300 kW, at time [0:25], the charging rate SOC of the storage device 32 lator is the upper limit SOC upper When SOC is greater than lator >SOC upper ), the correction value FC of the generated power FC of the fuel cell device 31 sub However, when the calculated SOC is -15kW, the generated power FC of the fuel cell device 31 is corrected to 285kW (FC=300kW-15kW). lator But SOCupper It is calculated as the value below.

[0058] In addition, the planned value FC of the power generation power FC of the fuel cell device 31 main At 350 kW, at time [1:00], the charging rate SOC of the storage device 32 lator is the upper limit SOC upper When SOC is greater than lator >SOC upper ), the correction value FC of the generated power FC of the fuel cell device 31 sub However, when the calculated SOC is -5kW, the generated power FC of the fuel cell device 31 is corrected to 345kW (FC=350kW-5kW). lator But SOC upper It is calculated as the value below.

[0059] SOC of the power storage device 32 lator Upper limit SOC is less than 100% upper If it is not greater than the planned value FC main will remain as is.

[0060] The operation of the power control device 20 in FIG. 4B will now be described.

[0061] First, the planned value FC of the generated power FC of the fuel cell device 31 is transmitted via the communication network. main is received.

[0062] When the distributed power supply system 30 supplies power to the power load 40 of the power consumer, as shown in FIG. 4B, in step S1, the planned value FC of the power generation power FC of the fuel cell device 31 is set to main An operation for controlling the generated power FC of the fuel cell device 31 is then performed.

[0063] Next, while the control of step S1 is being executed, in step S2B, the planned value FC of the generated power FC of the fuel cell device 31 is set to main The state of charge (SOC) of the power storage device 32 after a predetermined time is estimated based onlator Lower limit SOC is greater than 0% lower It is determined whether it is smaller than

[0064] Here, the "predetermined time" may be, for example, about 60 minutes, but is not limited to this. lower " may be, for example, about 10%, but is not limited to this.

[0065] SOC of the power storage device 32 lator Lower limit SOC is greater than 0% lower If it is smaller than the planned value FC main Specifically, a correction value FC of the generated power FC of the fuel cell device 31 is increased. sub is calculated, and the planned value FC of the generated power FC of the fuel cell device 31 is main In other words, the planned value FC main Correction value FC sub The generated power FC of the fuel cell device 31 is obtained by adding these values ​​together (FC=FC main +FC sub The above amendment is an example of the "second amendment" of the present disclosure.

[0066] For example, as shown in FIG. 5, the planned value FC of the generated power FC of the fuel cell device 31 main At 300 kW, at time [0:45], the charging rate SOC of the storage device 32 lator is the lower limit SOC lower When SOC lator <SOC lower ), the correction value FC of the generated power FC of the fuel cell device 31 sub However, when the calculated power output FC is +10 kW, the power output FC of the fuel cell device 31 is corrected to 310 kW (FC = 300 kW + 10 kW). lator But SOC lower It is calculated as a value equal to or greater than this.

[0067] In addition, the planned value FC of the power generation power FC of the fuel cell device 31main At 300 kW, at time [0:55], the charging rate SOC of the storage device 32 lator is the lower limit SOC lower When SOC lator <SOC lower ), the correction value FC of the generated power FC of the fuel cell device 31 sub However, when the calculated power output is +5kW, the power output FC of the fuel cell device 31 is corrected to 305kW (FC=300kW+5kW). lator But SOC lower It is calculated as a value equal to or greater than this.

[0068] SOC of the power storage device 32 lator Lower limit SOC is greater than 0% lower If it is not smaller than the planned value FC main will remain as is.

[0069] In addition, the "various times" and "planned value FC main " and "Correction value FC sub " are merely examples and are not limited to these examples. lator " and "Correction value FC sub A specific example of a method for calculating " will be described in the second embodiment.

[0070] According to the present embodiment described above, the possibility that the power storage device 32 becomes fully charged or completely discharged can be reduced compared to the conventional case.

[0071] Specifically, the planned value FC of the generated power FC of the fuel cell device 31 main When the power generation FC of the fuel cell device 31 is controlled, the planned value FC of the power generation FC of the fuel cell device 31 is set to main The state of charge (SOC) of the storage device after a predetermined time is estimated based on lator However, the upper limit SOC is less than 100%. upper When it is larger than this planned value FC mainBy making a correction to decrease the charge current, it is possible to appropriately reduce the possibility that the power storage device 32 will be fully charged, compared to the case where such a correction is not made. When the power storage device 32 is fully charged, reverse power flow from the distributed power system 30 to the power grid is likely to occur, but according to this embodiment, the above correction can suppress the occurrence of such reverse power flow.

[0072] In addition, the planned value FC of the power generation power FC of the fuel cell device 31 main When the power generation FC of the fuel cell device 31 is controlled, the planned value FC of the power generation FC of the fuel cell device 31 is set to main The state of charge (SOC) of the power storage device 32 after a predetermined time is estimated based on lator Lower limit SOC is greater than 0% lower When it is smaller than this planned value FC main By making a correction to increase , it is possible to appropriately reduce the possibility that the power storage device 32 will be in a fully discharged state, compared to a case where such a correction is not made. When the power storage device 32 is in a fully discharged state, power purchase from the power grid is likely to occur, but according to this embodiment, the above correction can suppress such power purchase.

[0073] (First embodiment) The power control method of this embodiment is similar to that of the first embodiment, except for the control content of the controller 22, which will be described below.

[0074] FIG. 6 is a diagram for explaining an example of the operation of the power control device (power control method) in the first example of the first embodiment.

[0075] As shown in FIG. 6, the planned value FC in step S3A in FIG. main or the planned value FC in step S3B of FIG. 4B main The correction is maintained for a certain period T sub is the planned value FC of the power generation FC of the fuel cell device 31 main A predetermined period T during which main is shorter than.

[0076] Here, "predetermined period T sub" is an example of the "first predetermined period" of the present disclosure. main " is an example of the "second predetermined period" of the present disclosure, and is fixed to an appropriate length so as to suppress the deterioration of the life span of the fuel cell device 31. main " may be, for example, about 60 minutes, but is not limited to this.

[0077] For example, in FIG. 6, a planned value FC of the generated power FC of the fuel cell device 31 is main is maintained at 300kW for a given period T main As a result, the 60 minutes between time [0:00] and time [1:00] are shown.

[0078] FIG. 6 also shows a planned value FC of the generated power FC of the fuel cell device 31. main is maintained at 350kW for a given period T main As a result, 60 minutes from time [1:00] to time [2:00] are shown.

[0079] FIG. 6 shows the planned value FC of step S3A in FIG. main Correction (FC main -20kW) is maintained for a specified period T sub As a result, the 5 minutes between time [0:20] and time [0:25] are shown.

[0080] In addition, the planned value FC in step S3A of FIG. main Correction (FC main -15kW) is maintained for a specified period T sub As a result, the 20 minutes between time [0:25] and time [0:45] are shown.

[0081] In other words, the planned value FC main Correction (FC main -20kW) is performed, and then for a specified period T main (60 minutes) in the middle of the day, the planned value FC main Further correction of (FC main -15kW) is performed, the former correction (FC main -20kW) will be reset.

[0082] FIG. 6 shows the planned value FC of step S3B of FIG. 4B. main Correction (FC main +10kW) is maintained for a specified period T sub As shown, the 10 minutes between time [0:45] and time [0:55] are shown.

[0083] In addition, the planned value FC in step S3B of FIG. main Correction (FC main +5kW) is maintained for a specified period T sub As shown, the 5 minutes between time [0:55] and time [1:00] are shown.

[0084] In other words, the planned value FC main Correction (FC main +10kW) is performed, and then for a specified period T main (60 minutes) in the middle of the day, the planned value FC main Further correction of (FC main +5kW) is performed, the former correction (FC main +10kW) will be reset.

[0085] Further, FIG. 6 shows the planned value FC of step S3A of FIG. main Correction (FC main -5kW) is maintained for a specified period T sub As a result, the 60 minutes between time [1:00] and time [2:00] are shown.

[0086] That is, the planned value FC of the generated power FC of the fuel cell device 31 main The timing of switching and the correction (FC main -5kW) is performed at the same time, the correction (FC main -5kW) will be carried out.

[0087] This amendment (FC main -5kW) was performed, and then the planned value FC main Unless further correction is made, the period T main (60 minutes), this correction (FCmain -5kW) will continue. And this correction (FC main -5kW) is the planned value FC of the power generation FC of the fuel cell device 31 main is reset when the switchover occurs.

[0088] In addition, the "various times," "various periods," and "planned values ​​FC main " and "Correction value FC sub " are merely examples and are not limited to these examples.

[0089] According to this embodiment, the planned value FC of the generated power FC of the fuel cell device 31 is main A predetermined period T during which main is fixed to a relatively long predetermined period (for example, 60 minutes), which is advantageous for extending the life of the fuel cell device 31. In other words, the more the number of times the output of the fuel cell device 31 changes, the more likely the fuel cell is to deteriorate. Therefore, in this embodiment, the predetermined period T main By fixing the length of the output of the fuel cell device 31 at an appropriate length, the number of output changes of the fuel cell device 31 is appropriately limited.

[0090] In addition, the planned value FC in step S3A of FIG. main or the planned value FC in step S3B of FIG. 4B main The correction is maintained for a certain period T sub is the planned value FC of the power generation FC of the fuel cell device 31 main A predetermined period T during which main The correction value FC of the generated power FC of the fuel cell device 31 is shorter than sub is the planned value FC of the power generation FC of the fuel cell device 31 main Since this change is small compared to the change in the current, the effect on the life of the fuel cell device 31 is small.

[0091] As a result of the above, according to this embodiment, the planned value FC of the generated power FC of the fuel cell device 31 is main A predetermined period T during which main The life of the fuel cell device 31 can be extended compared to when the time is short and changes frequently.

[0092] A power control method, power control device 20, and power supply system 10 of this embodiment may be similar to those of the first embodiment except for the above-mentioned features.

[0093] (Second Example) The power control method of this embodiment is similar to that of the first embodiment, except for the control content of the controller 22, which will be described below.

[0094] FIG. 7 is a diagram for explaining an example of the operation of the power control device (power control method) in the second example of the first embodiment.

[0095] As shown in FIG. 7, the planned value FC of the generated power FC of the fuel cell device 31 is main In a predetermined period TA before the change of the planned value FC in step S3A of FIG. 4A or step S3B of FIG. 4B, main The "predetermined period TA" is an example of the "third predetermined period" of the present disclosure.

[0096] In addition, the planned value FC of the power generation power FC of the fuel cell device 31 main In a predetermined period TB after the switching of the planned value FC main The "predetermined period TB" is an example of the "fourth predetermined period" of the present disclosure.

[0097] In the example shown in FIG. 7, the time [0:55] is included in the "predetermined period TA", so the charging rate SOC lator is the lower limit SOC lower Even if the planned value FC in step S3B of FIG. 4B is smaller than main correction is not performed.

[0098] The planned value FC of the generated power FC of the fuel cell device 31 is main At the timing when the switch occurs, the planned value FC main For example, as shown in FIG. 7, at time [1:00], the planned value FC main The power consumption will be changed from 300kW to 350kW, and the correction (FCmain -5kW) will be carried out.

[0099] Here, the "predetermined period TA" or the "predetermined period TB" is the planned value FC of the power generation of the fuel cell device 31. main After the switching, the output of the fuel cell device 31 becomes the switched planned value FC main The "predetermined period TA" and the "predetermined period TB" may be, for example, equal to or longer than the time required for the output of the fuel cell device 31 to reach a desired target value upon startup of a standby fuel cell unit in the fuel cell device 31.

[0100] In addition, the "various times," "various periods," and "planned values ​​FC main " and "Correction value FC sub " are merely examples and are not limited to these examples.

[0101] Planned value FC of the power generation of the fuel cell device 31 main In a predetermined period before and after the timing of switching, the planned value FC main When the correction is performed, the planned value FC of the generated power FC of the fuel cell device 31 is main There may be cases where the period during which the output of the fuel cell device 31 changes based on the above-mentioned correction overlaps with the period during which the output of the fuel cell device 31 changes based on the above-mentioned correction.

[0102] In other words, a certain amount of time is required for the output of the fuel cell device 31 to reach a desired target value. main When the above correction is performed immediately before the switching of the fuel cell device 31, the planned value FC of the generated power FC of the fuel cell device 31 is changed while the output of the fuel cell device 31 is changing based on the correction. main If this occurs, it may become difficult to control the output of the fuel cell device 31 according to the planned power generation FC of the fuel cell device 31.

[0103] In addition, the planned value FC of the power generation power FC of the fuel cell device 31 main Immediately after the timing at which the planned value FC of step S3A in FIG. 4A or step S3B in FIG. 4B is switched, main When the correction is performed, the planned value FC of the generated power FC of the fuel cell device 31 is main While the output of the fuel cell device is changing based on the above, a change in the output of the fuel cell device 31 may be instructed based on the above correction. If this happens, it may become difficult to control the output of the fuel cell device 31 in accordance with the correction of the generated power FC of the fuel cell device 31.

[0104] However, according to this embodiment, the planned value FC of the generated power FC of the fuel cell device 31 main The specified period TA before the change or the planned value FC main In a predetermined period TB after the change, the planned value FC main By prohibiting the execution of the correction, it becomes easier to appropriately control the output of the fuel cell device 31 compared to a case in which the execution of the correction is not prohibited.

[0105] According to this embodiment, the predetermined period TA or the predetermined period TB is set based on the planned value FC of the generated power FC of the fuel cell device 31. main After the switching, the output of the fuel cell device 31 becomes the switched planned value FC main By setting the predetermined period TA and the predetermined period TB to be longer than the time required for the planned value FC of the generated power FC of the fuel cell device 31 to be reached, the planned value FC of the generated power FC of the fuel cell device 31 can be reduced in comparison with a case where the predetermined period TA and the predetermined period TB are shorter than the required time. main The period during which the output of the fuel cell device 31 changes based on the planned value FC in step S3A of FIG. 4A or step S3B of FIG. 4B. main Therefore, it is possible to appropriately reduce the possibility that the period during which the output of the fuel cell device 31 changes based on the correction of the above-mentioned difference will overlap with the period during which the output of the fuel cell device 31 changes based on the correction of the above-mentioned difference.

[0106] Other than the above-mentioned features, the power control method, power control device 20, and power supply system 10 of this embodiment may be similar to those of the first embodiment or the first example of the first embodiment.

[0107] (Third Example) The power control method of this embodiment is similar to that of the first embodiment, except for the control content of the controller 22, which will be described below.

[0108] FIG. 8 is a diagram for explaining an example of the operation of the power control device (power control method) in the third example of the first embodiment.

[0109] As shown in FIG. 8, the planned value FC main After the execution of the correction is started, the predetermined period TC is set to the planned value FC main The "predetermined period TC" is an example of the "fifth predetermined period" of the present disclosure.

[0110] In the example shown in FIG. 8, the time [0:25] is included in the "predetermined period TC", so the charging rate SOC lator is the upper limit SOC upper Even if the planned value FC in step S3A of FIG. 4A is larger than main correction is not performed.

[0111] Here, the "predetermined period of time TC" may be, for example, a time or longer until the output of the fuel cell device 31 reaches a desired target value due to startup of a standby fuel cell unit in the fuel cell device 31.

[0112] In addition, the "various times," "various periods," and "planned values ​​FC main " and "Correction value FC sub " are merely examples and are not limited to these examples.

[0113] A certain amount of time is required for the output of the fuel cell device 31 to reach the desired target value. mainIf the correction is executed again immediately after the execution of the correction in step (1), there is a possibility that while the output of the fuel cell device 31 is changing based on the former correction, a change in the output of the fuel cell device 31 may be instructed based on the latter correction. This may make it difficult to control the output of the fuel cell device 31 in accordance with the correction of the generated power FC of the fuel cell device 31.

[0114] However, according to this embodiment, the planned value FC in step S3A of FIG. 4A or step S3B of FIG. 4B main After the execution of the correction is started, the correction is prohibited from being executed again for a predetermined period TC, so that the planned value FC in step S3A of FIG. 4A and step S3B of FIG. 4B is main In this case, it becomes easier to appropriately control the output of the fuel cell device 31 compared to when re-execution of the correction is not prohibited.

[0115] Other than the above-mentioned features, the power control method, power control device 20, and power supply system 10 of this embodiment may be similar to any of the first embodiment and the first to second examples of the first embodiment.

[0116] (Fourth Example) The power control method of the present embodiment is similar to that of the first embodiment, except for the configuration of a distributed power system 130 and the control content of the controller 22, which will be described below.

[0117] FIG. 9 is a diagram illustrating an example of a distributed power supply system included in a power supply system according to a fourth example of the first embodiment.

[0118] 9, the distributed power system 130 includes a fuel cell device 31, a power storage device 32, and a solar power generation device 33. Here, the configurations of the fuel cell device 31 and the power storage device 32 are similar to those in the first embodiment, and therefore description thereof will be omitted.

[0119] The solar power generation device 33 is an electric power device that utilizes sunlight to convert light energy into electric power under the control of the power control device 20. The electric power generated by the solar power generation device 33 is supplied to the electric power load 40, the electric power system, or the electric storage device 32. As the solar power generation device 33, a well-known device can be used.

[0120] The power supply system 10 may be, for example, a system that supplies large amounts of power to a power grid. In this case, the fuel cell device 31, the solar power generation device 33, and the power storage device 32 each include a fuel cell unit group consisting of a plurality of fuel cell units including a fuel cell stack, a solar cell group consisting of a plurality of solar cells including a solar panel, and a storage battery unit group consisting of a plurality of storage battery units, respectively, and the detailed configuration of such a power supply system 10 will be described in the second embodiment.

[0121] In this embodiment, the planned value FC of the generated power FC of the fuel cell device 31 is main When the power generation power FC of the fuel cell device 31 is controlled, the actual value of the power demand of the power consumer in the immediately preceding predetermined period TD, the actual value of the power generation power FC of the solar power generation device 33, and the planned value FC of the power generation power FC of the fuel cell device 31 are calculated. main The charging rate SOC of the power storage device 32 after a predetermined time from the difference between the sum of lator The "predetermined period TD" is an example of the "sixth predetermined period" of the present disclosure. The "predetermined period TD" may be, for example, about 15 minutes, but is not limited thereto.

[0122] Here, the power demand of the power consumer and the power generated by the solar power generation device 33 are measured by the controller 22 at an appropriate sampling period, and the sampling data is stored in the power database as actual values. Therefore, the controller 22 can obtain the actual values ​​of the power demand of the power consumer and the actual values ​​of the power generated by the solar power generation device 33 during a predetermined period TD from the power database.

[0123] According to this embodiment, the immediately preceding actual value of the power demand of the power consumer, the immediately preceding actual value of the photovoltaic power generation device 33, and the planned value FC of the generated power FC of the fuel cell device 31 are calculated. main Since the difference between the sum of the two corresponds to the charging power or discharging power of the power storage device 32, the charging rate SOC of the power storage device 32 after a predetermined time is calculated based on the difference. lator can be appropriately estimated.

[0124] Other than the above-mentioned features, the power control method, power control device 20, and power supply system 10 of this embodiment may be similar to any of the first embodiment and the first to third examples of the first embodiment.

[0125] Second embodiment [Device configuration] Fig. 10 is a diagram showing an example of a power supply system according to the second embodiment. In Fig. 10, for the sake of convenience, solid lines and dashed lines respectively indicate paths along which power is transmitted and paths along which signals are transmitted.

[0126] As shown in FIG. 10, the power supply system 10 of this embodiment includes a power control device 20, a fuel cell device 31, a power storage device 32, a solar power generation device 33, and control devices 50A to 50C.

[0127] Here, the internal configuration of the power control device 20 is similar to that of the first embodiment, and therefore a detailed description thereof will be omitted.

[0128] 10, the fuel cell device 31 includes a fuel cell unit group consisting of a plurality of fuel cell units. The fuel cell unit group is divided into a plurality of groups according to the plurality of fuel cell units, and the plurality of fuel cell units in each group are connected to the power grid via a power conditioner (PCS) and a power meter. The power meter is connected to the power control device 20 by a communication network. The number of fuel cell units in each group is set to an appropriate value depending on the output specifications of the power supply system 10, etc.

[0129] Although not shown, each of these fuel cell units is composed of auxiliary devices such as a fuel cell stack, a pump, and a valve, and a control device that controls the operation of these devices. If a control device is not provided in the fuel cell unit, the operation of the above devices may be directly controlled by the control device 50A.

[0130] The photovoltaic power generation device 33 includes a solar cell group consisting of a plurality of solar cells including a solar panel. The solar cell group is divided into a plurality of groups each of which is made up of a plurality of solar cells, and the plurality of solar cells in each group are connected to the power grid via a power conditioner (PCS) and a power meter. The power meter is connected to the power control device 20 by a communication network. The number of solar cells in each group is set to an appropriate value depending on the output specifications of the power supply system 10, etc.

[0131] The power storage device 32 includes a storage battery unit group consisting of a plurality of storage battery units. The storage battery unit group is divided into a plurality of groups each including a plurality of storage battery units, and the plurality of storage battery units in each group are connected to the power grid by power lines via a power conditioner (PCS) and a power meter. The power meter is connected to the power control device 20 by a communication network. The number of storage battery units in each group is set to an appropriate value depending on the output specifications of the power supply system 10, etc.

[0132] Furthermore, the fuel cell device 31, the power storage device 32 and the solar power generation device 33 are connected in parallel to each other via a power grid, and are also connected to a power load 40 of a power consumer via a power meter. This power meter is connected to the power control device 20 by a communication network.

[0133] However, the above configuration of the power supply system 10 is merely an example and is not limited to this example. For example, the fuel cell unit group may be grouped by a single group of multiple fuel cell units, or may be grouped by a single fuel cell unit in each group. The solar cell group may be grouped by a single group of multiple solar cells, or may be grouped by a single solar cell in each group. The storage battery unit group may be grouped by a single group of multiple storage battery units, or may be grouped by a single storage battery unit in each group.

[0134] The control devices 50A to 50C are provided corresponding to the fuel cell device 31, the power storage device 32 and the solar power generation device 33, respectively, and are connected to the power control device 20 via a communications network.

[0135] For example, the control device 50A controls the output of each of these fuel cell units via a communication network so as to enable efficient operation (e.g., optimization of the life span) of the fuel cell units. Also, for example, the control device 50C may adjust the output of the photovoltaic power generation device 33 by controlling a power conditioner (PCS) via a communication network, and may disconnect or connect a desired number of solar cells to or from the power grid.

[0136] However, the above is merely an example and is not limited to this example. For example, the controller 22 (see FIG. 3) of the power control device 20 may directly control the operation of the devices corresponding to the control devices 50A-50C, without going through the control devices 50A-50C. Furthermore, the power control device 20 may be integrated with the control devices 50A-50C, in other words, equipped with the control functions of the control devices 50A-50C, and directly control the operation of the devices corresponding to the control devices 50A-50C.

[0137] The control devices 50A-50C may have any control function, and include a calculation processing unit (not shown), a storage unit that stores a control program, and a communication device. The calculation processing unit reads out and executes the control program stored in the storage unit, thereby performing predetermined control in the control devices 50A-50C. An example of the calculation processing unit is a microprocessor. An example of the storage unit is a memory.

[0138] [Operation] 11A and 11B are flowcharts showing an example of the operation (power control method) of the power control device of the second embodiment.

[0139] The following operations may be performed, for example, by the calculation processing unit of the controller 22 reading out a control program from the storage unit of the controller 22. However, it is not essential that the following operations are performed by the controller 22. An operator may perform some of the operations. In the following example, a case where the operations are controlled by the controller 22 will be described.

[0140] The operation of the power control device 20 in FIG. 11A will now be described.

[0141] First, in step S11, the planned value FC of the generated power FC of the fuel cell device 31 is calculated from the power database. main The charging rate SOC of the power storage device 32, the power demand D during a sampling period (predetermined period TD), and the solar cell generated power PV are acquired. The sampling period (TD) is set to a time shorter than a predetermined time (T) described later. The "sampling period" may be, for example, about 15 minutes, but is not limited to this.

[0142] Then, in step S12, the moving average value D of the power demand D during the sampling period (predetermined period TD) is calculated. ave and the moving average value of solar cell power generation PV ave is calculated.

[0143] Next, in step S13, the charging power or discharging power of the power storage device 32, B pre1 is calculated by the following formula (1). B pre1 =D ave -(PV ave +FC main ) · · · (1)

[0144] In addition, B pre1 When it is >0, it means the discharge power of the storage device 32, and B pre1 When it is <0, it means the charging power of the power storage device 32.

[0145] Next, in step S14, the charging rate SOC of the power storage device 32 after a predetermined time (T) has elapsed is calculated. lator is calculated by the following formula (2): Here, the "predetermined time (T)" is the planned value FC of the generated power FC of the fuel cell device 31 from the viewpoint of suppressing the shortening of the life span of the fuel cell device 31. main A predetermined period T during which main The predetermined time (T) may be about 60 minutes, but is not limited to this. SOC lator =SOC-(B pre1 ×T) / Capacity of storage device (2)

[0146] Next, in step S15A, the charging rate SOC lator is the upper limit SOC upper It is determined whether it is greater than

[0147] Charging rate SOC lator is the upper limit SOC upper If the answer is "Yes" in step S15A, then in step S16A, the charging power or discharging power of the power storage device 32 that satisfies the following formula (3A) is calculated as B pre2 is calculated. SOC upper =SOC-(B pre2 ×T) / power storage device capacity...(3A)

[0148] In addition, B pre2 When it is >0, it means the discharge power of the storage device 32, and Bpre2 When it is <0, it means the charging power of the power storage device 32.

[0149] Next, in step S17A, a correction value FC of the generated power FC of the fuel cell device 31 that satisfies the following formula (4A) is calculated. sub is calculated (FC sub <0). B pre2 =D ave -(PV ave +FC main +FC sub ) · · · (4A)

[0150] Then, in step S18A, the power generation power FC of the fuel cell device 31 is calculated using the following equation (5A), and the power generation power FC corrected from the planned value of the power generation power of the fuel cell device 31 is commanded, provided that the timing does not fall under the "predetermined period TA" and "predetermined period TB" of the second example of the first embodiment and the "predetermined period TC" of the third example of the first embodiment. FC=FC main +FC sub (5A)

[0151] On the other hand, charging rate SOC lator is the upper limit SOC upper If it is not greater than FC (if "No" in step S15A), the generated power FC of the fuel cell device 31 is maintained as it is. sub But the charging rate SOC lator and upper limit SOC upper However, the charging rate SOC is determined so as to be equal to the charging rate SOC. lator However, the upper limit SOC upper Less than FC sub may be determined.

[0152] The operation of the power control device 20 in FIG. 11B will now be described.

[0153] It should be noted that steps S11 to S14 in FIG. 11B are similar to steps S11 to S14 in FIG. 11A, and therefore the description thereof will be omitted.

[0154] In step S15B, the charging rate SOC lator is the lower limit SOC lower It is determined whether it is smaller than

[0155] Charging rate SOC lator is the lower limit SOC lower If the answer is "Yes" in step S15B, then in step S16B, the charging power or discharging power of the power storage device 32 that satisfies the following formula (3B) is calculated as B pre2 is calculated. SOC lower =SOC-(B pre2 ×T) / power storage device capacity...(3B)

[0156] Next, in step S17B, a correction value FC of the generated power FC of the fuel cell device 31 that satisfies the following formula (4B) is calculated. sub is calculated (FC sub >0). B pre2 =D ave -(PV ave +FC main +FC sub ) · · · (4B)

[0157] Then, in step S18B, the power generation power FC of the fuel cell device 31 is calculated using the following equation (5B), and the power generation power FC corrected from the planned value of the power generation power of the fuel cell device 31 is commanded, provided that the timing does not fall under the "predetermined period TA" and "predetermined period TB" of the second example of the first embodiment and the "predetermined period TC" of the third example of the first embodiment. FC=FC main +FC sub (5B)

[0158] On the other hand, charging rate SOC lator is the lower limit SOC lower If it is not smaller than FC (if "No" in step S15B), the generated power FC of the fuel cell device 31 is maintained as it is. sub But the charging rate SOC lator and upper limit SOC lowerHowever, the charging rate SOC is determined so as to be equal to the charging rate SOC. lator However, the lower limit SOC lower FC to get bigger sub may be determined.

[0159] The effects and advantages of the power control method, power control device 20, and power supply system 10 of this embodiment can be easily understood from the description of the effects and advantages of the power control device 20 and power supply system 10 of the first embodiment, so a description thereof will be omitted.

[0160] Other than the above-mentioned features, the power control method, power control device 20, and power supply system 10 of this embodiment may be similar to any of the first embodiment and the first to fourth examples of the first embodiment.

[0161] The first embodiment, the first to fourth examples of the first embodiment, and the second embodiment may be combined with each other as long as they are not mutually exclusive. From the above description, many improvements and other embodiments of the present disclosure will be apparent to those skilled in the art. Therefore, the above description should be construed as merely illustrative and is provided for the purpose of teaching those skilled in the art the best mode for carrying out the present disclosure. The details of the structure and / or function thereof may be substantially changed without departing from the spirit of the present disclosure. [Industrial Applicability]

[0162] INDUSTRIAL APPLICABILITY One embodiment of the present disclosure can be used in a power control method, a power control device, and a power supply system that can reduce the possibility that a power storage device will be fully charged or completely discharged compared to conventional methods. [Explanation of symbols]

[0163] 10: Power supply system 20: Power control device 21: Memory device 22: Controller 30: Distributed power systems 31:Fuel cell device 32: Electricity storage device 33: Solar power generation equipment 40: Power load 50A: Control device 50B: Control device 50C: Control device 130: Distributed power systems

Claims

1. When a distributed power supply system including a fuel cell device and a power storage device supplies power to a power load of a power consumer, controlling a power generation amount of the fuel cell device to a planned value of the power generation amount of the fuel cell device; and when the control is being executed, when the charging rate of the power storage device after a predetermined time period estimated based on the planned value is greater than an upper limit value less than 100%, executing a first correction to decrease the planned value, or when the charging rate of the power storage device after a predetermined time period estimated based on the planned value is less than a lower limit value greater than 0%, executing a second correction to increase the planned value.

2. The power control method according to claim 1 , wherein a first predetermined period during which the first correction or the second correction is maintained is shorter than a second predetermined period during which the planned value is maintained.

3. The power control method according to claim 1 , wherein the first correction or the second correction is not executed in a third predetermined period before the planned value is switched or in a fourth predetermined period after the planned value is switched.

4. 4. The power control method according to claim 3, wherein the third specified period or the fourth specified period is longer than or equal to the time required for the output of the fuel cell device to reach the planned value after the planned value is switched.

5. The power control method according to claim 1 , wherein the first correction or the second correction is not executed for a fifth predetermined period after starting execution of the first correction or the second correction.

6. The distributed power system further includes a solar power generation device, 2. The power control method according to claim 1, wherein, when the control is being performed, a charging rate of the power storage device after a predetermined time is estimated from a difference between an actual value of the power demand of the power consumer in an immediately preceding sixth predetermined period and a sum of an actual value of the power generated by the solar power generation device and the planned value.

7. A power control device for a distributed power supply system including a fuel cell device and a power storage device, a memory for storing a planned value of the power generation power of the fuel cell device; a controller that controls the power generation power of the fuel cell device to a planned value of the power generation power of the fuel cell device when power is supplied from the distributed power supply system to a power load of a power consumer; The controller, when executing the control, performs a first correction to decrease the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is greater than an upper limit value less than 100%, or performs a second correction to increase the planned value when the charging rate of the power storage device after a predetermined time estimated based on the planned value is less than a lower limit value greater than 0%.

8. A fuel cell device; A power storage device; A power supply system comprising the power control device according to claim 7.

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