Method for operating power system and device for controlling power system

Abstract

A method for operating a power system according to the present disclosure includes a step of planning an output of a fuel cell system so as to compensate for a difference between a power demand and an output of a solar power generation system, when the charging rate of a storage battery system is equal to or greater than an upper limit value less than 100%, a first correction is performed that corrects the plan so that the output of the fuel cell system is reduced. And at least one of a second correction for correcting the plan so as to increase the output of the fuel cell system when the charging rate of the storage battery system is equal to or less than a lower limit value that is greater than 0%.

Description

Technical Field

[0001] The present disclosure relates to an operation method of a power system for supplying electric power, etc. Background Art

[0002] Conventionally, a power supply system for supplying electric power has been proposed (for example, refer to Patent Document 1). This power supply system includes a power conditioner device for adjusting the electric power supplied from a solar power generation device as a natural energy power generation device, a storage battery, a hydrogen production device, and a fuel cell. Further, the power supply system supplies the electric power obtained from the solar power generation device, the storage battery, and the fuel cell to a facility, and further supplies the surplus electric power to the storage battery or the hydrogen production device. In addition, the power supply system predicts the power generation amount of the solar power generation device, and based on the predicted power generation amount, that is, the predicted value, etc., determines the amount of electric power charged and discharged by the storage battery, the amount of electric power supplied to the hydrogen production device, and the amount of electric power supplied from the fuel cell. Thereby, it is possible to continuously supply electric power that satisfies the facility demand.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: International Publication No. 2017 / 013751 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, in the operation method of the power supply system, that is, the power system including the solar power generation device, the storage battery, and the fuel cell in Patent Document 1 above, since the charging amount of the storage battery is not sufficiently considered, there are the following problems: It is impossible to use the storage battery to absorb the surplus electric power of the solar power generation device, resulting in a reverse flow to the power organization (power authority), and the charging amount of the storage battery is insufficient, so it is impossible to meet the power demand of the load, and it may be necessary to purchase electric power from the power organization.

[0008] Therefore, the present disclosure provides an operation method of a power system, etc., which can reduce the reverse flow to the power organization or the purchase of electric power from the power organization by considering the charging amount of the storage battery.

[0009] Technical Means for Solving the Problems

[0010] A method for operating a power system according to an aspect of the present disclosure includes a step of planning an output of a fuel cell system in a manner that compensates for a difference between a power demand amount and an output of a solar power generation system. In this step, at least one of a first correction for correcting the plan in a manner that reduces the output of the fuel cell system when a charging rate of a battery system is equal to or higher than an upper limit value less than 100%, and a second correction for correcting the plan in a manner that increases the output of the fuel cell system when the charging rate of the battery system is equal to or lower than a lower limit value greater than 0% is performed.

[0011] Furthermore, these general or specific aspects can be implemented by a system, a method, an integrated circuit, a computer program, or a recording medium such as a computer-readable CD-ROM, or can be implemented by any combination of a system, a method, an integrated circuit, a computer program, and a recording medium. Additionally, the recording medium can also be a non-transitory recording medium.

[0012] Effects of the Invention

[0013] The method for operating a power system of the present disclosure can seek to reduce power backflow to the power organization or power purchase from the power organization by considering the charge amount of the battery.

[0014] Further advantages and effects in an aspect of the present disclosure will be made clear from the specification and the drawings. Although these advantages and / or effects are provided separately by some embodiments and the configurations described in the specification and the drawings, it is not necessary to provide all the configurations to obtain these advantages and effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 FIG. is a diagram showing a configuration example of an entire system including a power system and a control device for the power system in an embodiment.

[0016] Figure 2 FIG. is a diagram for explaining an output of a fuel cell power generation device planned by a control device in an embodiment.

[0017] Figure 3 FIG. is a block diagram showing an example of a functional configuration of a control device in an embodiment.

[0018] Figure 4 FIG. is a diagram showing an example of generated power of a fuel cell power generation device and charge / discharge power of a battery device controlled by a control device in an embodiment.

[0019] Figure 5 FIG. is a flowchart showing an example of a processing operation of a data acquisition unit in an embodiment.

[0020] Figure 6It is a flowchart showing an example of the processing operations of the fuel cell output calculation unit and the output correction unit in the embodiment.

[0021] Figure 7 It is a flowchart showing an example of the processing operations of the battery output calculation unit in the embodiment.

[0022] Figure 8 It is a flowchart showing an example of the processing operations of the third controller in the embodiment.

[0023] Figure 9 It is a diagram showing an example of the effects obtained from the operation mode of the control device in the embodiment. Detailed Embodiment

[0024] Regarding the power supply system of the above Patent Document 1, the following is described: The power generation amount of the solar power generation device is predicted based on the weather of the next day, and based on this prediction, the amount of power supplied from the solar power generation device to the battery and the water electrolysis device during the day of the current day and the amount of power supplied from the battery and the fuel cell to the facility during the night of the current day are adjusted.

[0025] Specifically, the following is described: In the case where it is estimated that the next day is sunny, during the night of the current day, the battery is preferentially used rather than the fuel cell to supply power to the facility to ensure the idle capacity of the battery, and the surplus power of the solar power generation device is preferentially supplied to the battery on the next day. However, generally, the power generation power and power demand of the solar power generation device vary greatly, and sometimes even on a sunny day, the power demand cannot be met by the power generation power of the solar power generation device and power from the battery is required. Therefore, even if it is estimated that the next day is sunny, it is necessary to face the next day with a certain amount of charge remaining in the battery to be able to cope with such a situation, but this is not considered.

[0026] In addition, the following is also described: In the case where it is estimated that the next day is rainy, during the night of the current day, the fuel cell is preferentially used rather than the battery to supply power to the facility to ensure a sufficient charge amount of the battery, and on the next day, not only the power of the solar power generation device but also the power of the battery and the fuel cell are supplied to the facility. However, generally, the power generation power and power demand of the solar power generation device vary greatly, and sometimes even on a rainy day, there is surplus power generated by the solar power generation device and it is necessary to use the battery to charge this surplus power. Therefore, even if it is estimated that the next day is rainy, it is necessary to face the next day with a certain amount of idle capacity remaining in the battery to be able to cope with such a situation, but this is not considered.

[0027] A method for operating a power system according to an aspect of the present disclosure includes a step of planning the output of a fuel cell system in a manner that compensates for the difference between the power demand and the output of a solar power generation system. In this step, at least one of a first correction for correcting the plan in a manner that reduces the output of the fuel cell system when the charge rate of the battery system is above an upper limit value less than 100%, and a second correction for correcting the plan in a manner that increases the output of the fuel cell system when the charge rate of the battery system is below a lower limit value greater than 0% is performed. In addition, the power system includes, for example, a solar power generation system, a fuel cell system, and a battery system. The solar power generation system includes a solar power generation device, the fuel cell system includes a fuel cell, and the battery system includes a battery. In addition, the power demand is, for example, the power consumption of a load possessed by a power user, and the outputs of the solar power generation system and the fuel cell system are, for example, generated power.

[0028] Accordingly, when the first correction is performed, the battery system can be discharged in a manner that compensates for the insufficient power with respect to the power demand due to the reduction in the output of the fuel cell system. Therefore, the possibility that the battery system becomes, for example, a fully charged state and the surplus power of the solar power generation system flows back to the power organization is reduced. In addition, when the second correction is performed, the discharge from the battery system is reduced by the increase in the output of the fuel cell system. Therefore, the possibility that the battery system becomes, for example, a fully discharged state and power is purchased from the power organization is reduced. In addition, since the possibility that the battery system becomes fully charged or fully discharged is reduced, the possibility of extending the life of the battery is increased.

[0029] In addition, in the case where the battery system includes a plurality of battery units, the charge rate of the battery system may also be the average value or the median value of the charge rates of these plurality of battery units. In addition, each of the power demand and the output of the solar power generation system may be an actual value or a predicted value. In the case where each of the power demand and the output of the solar power generation system is an actual value, the charge rate of the battery system may be the charge rate at the planned time point of the output of the battery system. In addition, in the case where each of the power demand and the output of the solar power generation system is a predicted value, the charge rate of the battery system may also be a predicted value.

[0030] In addition, a control device for a power system according to an aspect of the present disclosure includes: a memory that stores a power demand and an output of a solar power generation system; and a controller that, when planning an output of a fuel cell system in a manner that compensates for a difference between the power demand and the output of the solar power generation system, performs at least one of: a first correction that corrects the plan in a manner that reduces the output of the fuel cell system when a charging rate of a battery system is equal to or higher than an upper limit value less than 100%; and a second correction that corrects the plan in a manner that increases the output of the fuel cell system when the charging rate of the battery system is equal to or lower than a lower limit value greater than 0%.

[0031] Accordingly, the same operational effects as those of the above-described power system operation method can be achieved.

[0032] Hereinafter, embodiments will be specifically described with reference to the drawings.

[0033] In addition, the embodiments described below are all illustrative or specific examples. The numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, steps, order of steps, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure. In addition, among the constituent elements in the following embodiments, the constituent elements not described in the independent claims showing the most general concept are described as optional constituent elements.

[0034] In addition, each drawing is a schematic diagram and is not necessarily strictly illustrated. In addition, in each drawing, the same reference numerals are assigned to the same constituent components.

[0035] (Embodiment)

[0036] Figure 1 FIG. is a diagram showing a configuration example of an entire system including the power system and the control device for the power system in the present embodiment. In addition, in Figure 1 the power lines are shown by solid lines and the communication lines are shown by dashed lines.

[0037] In this embodiment, the power system 200 is connected to the power organization 100 and the load 301 via power lines. Moreover, the power system 200 supplies power to the load 301. In addition, the power organization 100 has a function of supplying power to the organization and is connected to the load 301 via power lines. Furthermore, the power for the organization is also referred to as commercial power, for example, AC power of 50 Hz or 60 Hz. Therefore, when the power supplied from the power system 200 is insufficient compared to the power consumption of the load 301, the power organization 100 supplies the insufficient amount of power to the load 301. On the other hand, when the power supplied from the power system 200 is surplus compared to the power consumption of the load 301, the surplus power is subscribed by the power organization 100, that is, the surplus power is sold as reverse power. In addition, the load 301 in this embodiment is composed of one or more machines, devices, equipment, etc. that consume power. Moreover, the power consumption of the load 301 is also referred to as the power demand. In addition, the load 301 is possessed by power users such as factories and facilities.

[0038] The power system 200 includes a solar power generation system a, a fuel cell system b, and a battery system c. The solar power generation system a includes a first controller 210, a solar power generation device 211, a first PCS (Power Conditioning System) 212, and a first power meter 213.

[0039] The solar power generation device 211, for example, has one or more solar power generation units, converts sunlight into power by photoelectric conversion, and outputs the power. The solar power generation unit is, for example, a solar power generation panel. In addition, the solar power generation device 211 is also simply referred to as a solar cell hereinafter. The first PCS 212 converts the power output from the solar power generation device 211 into power homogeneous with the power for the organization and outputs it. The first power meter 213 measures the power output from the solar power generation device 211 via the first PCS 212, that is, the power for the organization, and outputs a signal indicating the measured power to the control device 10. The first controller 210 controls the solar power generation device 211 and the first PCS 212. For example, the first controller 210 controls the solar power generation device 211 and the first PCS 212 according to an instruction from the control device 10.

[0040] The fuel cell system b includes a second controller 220, a fuel cell power generation device 221, a second PCS 222, and a second power meter 223.

[0041] The fuel cell power generation device 221 has, for example, one or more fuel cell units, and generates electricity by causing a chemical reaction between hydrogen and oxygen. The hydrogen source for power generation is, for example, a hydrogen storage device or a hydrogen infrastructure. The fuel cell unit is, for example, a fuel cell stack device. In addition, the fuel cell power generation device 221 is also simply referred to as a fuel cell hereinafter. The second PCS 222 converts the power output by the power generation of the fuel cell power generation device 221 into power homogeneous with the institutional power and outputs it. The second power meter 223 measures the power output from the fuel cell power generation device 221 via the second PCS 222, that is, the institutional power, and outputs a signal indicating the measured power to the control device 10. The second controller 220 controls the fuel cell power generation device 221 and the second PCS 222. For example, the second controller 220 adjusts the power output from the fuel cell power generation device 221 and the second PCS 222 according to an instruction from the control device 10.

[0042] The battery system c includes a third controller 230, a battery device 231, a third PCS 232, and a third power meter 233.

[0043] The battery device 231 has, for example, one or more battery units, and performs charging or discharging. The battery unit is, for example, a battery pack. In addition, the battery device 231 is also simply referred to as a battery hereinafter. The third PCS 232 converts the power output by the discharge of the battery device 231 into power homogeneous with the institutional power and outputs it. Alternatively, the third PCS 232 converts the institutional power and charges the battery device 231. The third power meter 233 measures the power output from the battery device 231 via the third PCS 232, that is, the institutional power, and outputs a signal indicating the measured power to the control device 10. In addition, the third power meter 233 measures the power output from the solar power generation device 211 or the fuel cell power generation device 221 and charged into the battery device 231, and outputs a signal indicating the measured power to the control device 10. The third controller 230 controls the battery device 231 and the third PCS 232. For example, the third controller 230 adjusts the power discharged from the battery device 231 or the power charged into the battery device 231 according to an instruction from the control device 10.

[0044] The control device 10 in the present embodiment is a control device for the power system 200, and is connected to the fourth power meter 303, the power system 200, and the database 20 via communication lines respectively. That is, the control device 10 communicates with the fourth power meter 303, the power system 200, and the database 20 via communication lines respectively. In addition, in the present embodiment, the power notified, sent, instructed, obtained, or received via the communication line is not the power itself, but data indicating the magnitude of the power such as wattage. Further, the fourth power meter 303 measures the power consumption of the load 301.

[0045] Such a control device 10 receives signals representing the power measured by the power meters from the first power meter 213, the second power meter 223, the third power meter 233, and the fourth power meter 303 respectively for each sampling period. And the control device 10 writes the power represented by these signals into the database 20. Further, the control device 10 receives a signal representing the SOC (State Of Charge) of the battery device 231 from the third controller 230 for each sampling period, and writes the SOC into the database 20. In addition, a specific example of the sampling period is 30 seconds or 1 minute, etc., but it is not limited to these times. Also, the SOC of the battery device 231 is the charging rate of the battery device 231, and is hereinafter also referred to as the battery SOC.

[0046] The database 20 is a recording medium for recording power values, battery SOC, etc. In addition, this recording medium is a hard disk drive, RAM (Random Access Memory), ROM (Read Only Memory), or semiconductor memory, etc. Also, this recording medium can be volatile or non-volatile. In addition, in the present embodiment, the database 20 is not provided in the control device 10, but it can also be provided in the control device 10.

[0047] Figure 2 It is a diagram for explaining the output of the fuel cell power generation device 221 planned by the control device 10. Specifically, Figure 2 The graph of () schematically shows the power at each moment. The horizontal axis of the graph represents the moment, and the vertical axis represents the power (kW).

[0048] As Figure 2As shown in the graph, the control device 10 in the present embodiment plans, for example, the output of the fuel cell power generation device 221 during the planned time point at "12:00", that is, the generated power FC of the fuel cell power generation device 221 during the control period T2. In addition, the control period T2 is also referred to as the second period. In a specific example, the control period T2 is 1 hour from the time point of "12:00" to "13:00".

[0049] More specifically, the control device 10 reads out from the database 20 the power consumption D of the load 301 and the generated power PV of the solar power generation device 211 during the sampling period T1 that is after the planned time point. That is, the control device 10 reads out the past power consumption D of the load 301 and the past generated power PV of the solar power generation device 211 obtained for each of the above sampling periods during the sampling period T1. And the control device 10 plans the generated power FC of the fuel cell power generation device 221 during the control period T2 in such a way as to make up for the difference between the power consumption D of the load 301 and the generated power PV of the solar power generation device 211 during the sampling period T1. In addition, the sampling period T1 is also referred to as the first period. In a specific example, when the sampling period is 1 minute, the sampling period T1 corresponding to the control period T2 is 15 minutes from the time point of "11:44" to "11:59". In this case, 15 differences are obtained during the sampling period T1. In addition, when the sampling period is 30 seconds, the sampling period T1 corresponding to the control period T2 can also be 15 minutes from the time point of "11:44:30" to "11:59:30". In this case, 30 differences are obtained during the sampling period T1.

[0050] And the control device 10 controls the fuel cell power generation device 221 and the second PCS 222 via the second controller 220 in such a way as to output the planned generated power FC of the fuel cell power generation device 221 during the control period T2.

[0051] Furthermore, when the fuel cell power generation device 221 generates the planned generated power FC during the control period T2, the control device 10 controls the battery device 231 and the third PCS 232 via the third controller 230. Specifically, when the sum of the generated power PV of the solar power generation device 211 and the generated power FC of the fuel cell power generation device 221 is greater than the power consumption D of the load 301, the control device 10 charges the battery device 231. On the other hand, when the sum is less than the power consumption D, the control device 10 discharges the battery device 231 in such a way as to meet the power consumption D.

[0052] In addition, the power consumption D of the load 301 is the power measured by the fourth power meter 303. Further, the power generation PV of the solar power generation device 211 is the power output from the solar power generation device 211 via the first PCS 212 and is measured by the first power meter 213. The power generation PV of such a solar power generation device 211 can also be said to be the output of the solar power generation system a or the solar power generation device 211. Similarly, the power generation FC of the fuel cell power generation device 221 is the power output from the fuel cell power generation device 221 via the second PCS 222 and is the power measured by the second power meter 223. The power generation FC of such a fuel cell power generation device 221 can also be said to be the output of the fuel cell system b or the fuel cell power generation device 221.

[0053] As such, in the present embodiment, the first period as the sampling period T1 is the period immediately before the second period as the control period T2. Further, the second period is longer than the first period, and the planned output of the fuel cell system b is constant during the second period. In addition, the output of the fuel cell system b corresponds to the power generation FC of the fuel cell power generation device 221. Here, in the present embodiment, the period immediately before the second period refers to the period from the following start time point to the end time point. That is to say, the end time point is the measurement time point of each of the plurality of powers recorded in the database 20 that is the closest measurement time point from the above-mentioned planned time point. And the start time point is the time point obtained by tracing back the sampling period T1 from this end time point, for example, the time point 15 minutes back. However, the first period as the period immediately before the second period is only an example and is not limited to the present embodiment. For example, the start time point of the first period may also be a time point after tracing back the second period from the planned time point as the start time point of the second period. In other words, the first period only needs to be earlier than the start time point of the second period and later than the start time point of the second period by the second period, and can be arbitrary. In addition, the first period only needs to be shorter than the second period, and is not limited to 15 minutes, and may also be 30 minutes or the like. In other words, the first period may be a period of 1 / 2 or less of the second period.

[0054] In addition, in the operation method of the power system 200 based on the control device 10 in the present embodiment, as described above, based on the difference between the actual value of the past power consumption D of the load 301 and the actual value of the past power generation PV of the solar power generation device 211, the output of the fuel cell power generation device 221 during the planned control period T2 is planned. Then, the fuel cell power generation device 221 outputs according to this plan. Therefore, in the operation method in the present embodiment, the output of the fuel cell power generation device 221 has priority over the output of the battery device 231. Thus, the operation method in the present embodiment is also referred to as a fuel cell priority application mode or a hydrogen priority application mode. This is because when the hydrogen source of the fuel cell power generation device 221 is, for example, a hydrogen storage tank or a hydrogen infrastructure, a larger output capacity than the battery device 231 can be ensured.

[0055] Figure 3 is a block diagram showing an example of the functional configuration of the control device 10. In addition, in Figure 3 for simplicity of explanation, the first PCS 212, the second PCS 222, and the third PCS 232 are omitted. In addition, in Figure 3 for easy understanding of the communication relationship between the respective components, the communication lines are shown by solid lines and the power lines are shown by dashed lines.

[0056] The control device 10 in the present embodiment includes a data acquisition unit 11, a fuel cell output calculation unit 12, an output correction unit 12a, and a battery output calculation unit 13.

[0057] The data acquisition unit 11 acquires signals representing four powers from the fourth power meter 303, the first power meter 213, the second power meter 223, and the third power meter 233 at each of the above sampling periods. And the data acquisition unit 11 writes the numerical values of these four powers as actual values into the database 20. The four powers are the power consumption D of the load 301, the power generation PV of the solar power generation device 211, the power generation FC of the fuel cell power generation device 221, and the discharge power Bd or the charge power Bc of the battery device 231. The discharge power Bd and the charge power Bc are collectively referred to as the charge-discharge power SB. Furthermore, the data acquisition unit 11 acquires a signal representing the battery SOC from the third controller 230 at each sampling period together with the above signals representing the four powers. And the data acquisition unit 11 writes this battery SOC as an actual value into the database 20.

[0058] In addition, the discharge power Bd of the battery device 231 in the present embodiment is the power discharged from the battery device 231 via the third PCS 232 and is the power measured by the third power meter 233. Similarly, the charging power Bc of the battery device 231 in the present embodiment is the power charged into the battery device 231 from the solar power generation device 211, the fuel cell power generation device 221, etc. via the third PCS 232 and is the power measured by the third power meter 233.

[0059] The fuel cell output calculation unit 12 reads out the power consumption D of the load 301 and the power generation PV of the solar power generation device 211 during the sampling period T1 closest to the planned time point from the database 20. Then, the fuel cell output calculation unit 12 uses the power consumption D and the power generation PV to calculate the power generation FC of the fuel cell power generation device 221 during the control period T2. Thus, the planned power generation FC is obtained. That is, the fuel cell output calculation unit 12 in the present embodiment plans the output of the fuel cell system b in a manner that compensates for the difference between the power demand and the output of the solar power generation system a. Specifically, the fuel cell output calculation unit 12 plans the output of the fuel cell system b, i.e., the power generation FC, during the second period of the control period T2, which is later than the first period of the sampling period T1, in a manner that compensates for the difference between the actual value of the power demand and the actual value of the output of the solar power generation system a during the first period of the sampling period T1. In addition, the output of the solar power generation system a corresponds to the power generation PV of the solar power generation device 211.

[0060] The output correction unit 12a reads out the latest battery SOC at the planned time point from the database 20. Then, the output correction unit 12a corrects the power generation FC planned by the fuel cell output calculation unit 12 based on the battery SOC. That is, the output correction unit 12a performs at least one of the first correction and the second correction. In the first correction, when the battery SOC is equal to or higher than the upper limit value less than 100%, the output correction unit 12a corrects the plan in a manner that reduces the output of the fuel cell system b. In the second correction, when the battery SOC is equal to or lower than the lower limit value greater than 0%, the output correction unit 12a corrects the plan in a manner that increases the output of the fuel cell system b.

[0061] The fuel cell output calculation unit 12 instructs the second controller 220 to generate the power generation FC via the communication line. The instructed power generation FC is the corrected power generation FC when the first correction or the second correction is performed, and is the power generation FC planned or calculated by the fuel cell output calculation unit 12 if neither the first correction nor the second correction is performed. The second controller 220 controls the fuel cell power generation device 221 and the second PCS 222 according to the instruction from the fuel cell output calculation unit 12.

[0062] When the fuel cell power generation device 221 generates the planned power generation power FC during the above control period T2, the battery output calculation unit 13 reads the latest three powers from the database 20 for each battery indication cycle. The three powers are the power consumption D of the load 301, the power generation power PV of the solar power generation device 211, and the power generation power FC of the fuel cell power generation device 221. In addition, a specific example of the battery indication cycle is 1 minute. Then, the battery output calculation unit 13 calculates the power that the battery device 231 should discharge or charge based on the three read powers. The battery output calculation unit 13 indicates the calculated power to the third controller 230 via the communication line. That is, the battery output calculation unit 13 outputs the discharge power indication value Bd' or the charge power indication value Bc' indicating the calculated power to the third controller 230. The third controller 230 controls the battery device 231 and the third PCS 232 according to the indication from the battery output calculation unit 13.

[0063] Figure 4 FIG. is an example showing the power generation power FC of the fuel cell power generation device 221 and the charge / discharge power SB of the battery device 231 controlled by the control device 10. Figure 4 FIG. (a) is a graph schematically showing the time changes of the power consumption D of the load 301 and the power generation power PV of the solar power generation device 211. Figure 4 FIG. (b) is a graph schematically showing the time change of the power generation power FC of the fuel cell power generation device 221 without being corrected by the output correction unit 12a. Figure 4 FIG. (c) is a graph schematically showing the time change of the charge / discharge power SB of the battery device 231. Figure 4 FIG. (d) is a graph schematically showing the time change of the battery SOC. Figure 4 FIG. (e) is a graph schematically showing the time change of the power generation power FC of the fuel cell power generation device 221 when the planned correction is performed by the output correction unit 12a. In addition, the horizontal axis of these graphs represents time, and the vertical axis represents power.

[0064] For example, as Figure 4 shown in FIG. (a), the power consumption D of the load 301 and the power generation power PV of the solar power generation device 211 change during the period from time "00:00" to time "24:00". Here, the fuel cell output calculation unit 12 of the control device 10 plans the power generation power FC of the fuel cell power generation device 221 during the control period T2 after the planned time point ta1 at the time ta1. At this time, the fuel cell output calculation unit 12 is such that as Figure 4As shown in (f), the generated power FC is calculated in such a way that the power consumption D of the load 301 during the sampling period T1 is equal to the sum of the generated power PV of the solar power generation device 211 and the generated power FC of the fuel cell power generation device 221. The calculated generated power FC is planned as the generated power FC of the fuel cell power generation device 221 during the control period T2 after the time ta1. Thereby, the reverse power and power purchase during the control period T2, that is, the surplus power and the deficit power, can be suppressed.

[0065] The fuel cell output calculation unit 12 repeatedly executes the calculation of such generated power FC with the control period T2 as one cycle. Here, assuming that the calculated generated power FC is not corrected, as shown in (b), the second controller 220 controls the fuel cell power generation device 221 in such a way that the uncorrected generated power FC before correction is output. Here, the fuel cell power generation device 221 has a rated output and a minimum output. For example, the rated output is 500 kW and the minimum output is 150 kW. Therefore, when the generated power FC indicated by the fuel cell output calculation unit 12 exceeds the rated output, the second controller 220 can cause the fuel cell power generation device 221 to perform power generation at the rated output. And when the generated power FC indicated by the fuel cell output calculation unit 12 is lower than the minimum output, the second controller 220 can cause the fuel cell power generation device 221 to perform power generation at the minimum output. Figure 4 And, the battery output calculation unit 13 calculates the charge and discharge power SB of the battery device 231 for each of the above battery indication periods. At this time, as shown in (g), the battery output calculation unit 13 calculates the charge and discharge power SB in such a way that the sum of the latest generated power PV of the solar power generation device 211, the latest generated power FC of the fuel cell power generation device 221, and the charge and discharge power SB of the battery device 231 is equal to the power consumption D of the latest load 301. Furthermore, the battery output calculation unit 13 instructs the third controller 230 to discharge or charge the charge and discharge power SB. That is, the battery output calculation unit 13 outputs a discharge power indication value Bd' or a charge power indication value Bc' to the third controller 230. As a result, as shown in (c), the third controller 230 controls the battery device 231 in such a way that the charge and discharge power SB is discharged or charged.

[0066] And, the battery output calculation unit 13 calculates the charge and discharge power SB of the battery device 231 for each of the above battery indication periods. At this time, the battery output calculation unit 13 Figure 4 As shown in (g), calculates the charge and discharge power SB in such a way that the sum of the latest generated power PV of the solar power generation device 211, the latest generated power FC of the fuel cell power generation device 221, and the charge and discharge power SB of the battery device 231 is equal to the power consumption D of the latest load 301. Furthermore, the battery output calculation unit 13 instructs the third controller 230 to discharge or charge the charge and discharge power SB. That is, the battery output calculation unit 13 outputs a discharge power indication value Bd' or a charge power indication value Bc' to the third controller 230. As a result, as shown in (c), the third controller 230 controls the battery device 231 in such a way that the charge and discharge power SB is discharged or charged. Figure 4 As shown in (c), the third controller 230 controls the battery device 231 in such a way that the charge and discharge power SB is discharged or charged.

[0067] That is, when the fuel cell system b is generating power at the planned output during the second period as the control period T2, the battery output calculation unit 13 in the present embodiment charges the battery system c when the sum of the output of the solar power generation system a and the output of the fuel cell system b is greater than the power demand. On the other hand, when the fuel cell system b is generating power at the planned output during the second period as the control period T2, the battery output calculation unit 13 discharges the battery system c in a manner that satisfies the power demand when the sum of the output of the solar power generation system a and the output of the fuel cell system b is less than the power demand. In addition, the charging and discharging of the battery system c correspond to the charging and discharging of the battery device 231.

[0068] In addition, during Figure 4 the period from time ta2 to time ta3 in, although the generated power PV of the solar power generation device 211 is large, the generated power FC of the fuel cell power generation device 221 cannot be reduced to less than the minimum output. Therefore, the remaining part of the generated power PV is charged into the battery device 231 as a large charging power Bc. On the other hand, during the period from time ta4 to time ta5, although the generated power PV of the solar power generation device 211 is small, the generated power FC of the fuel cell power generation device 221 cannot be increased to higher than the rated output. Therefore, the insufficient part of the generated power PV or the generated power FC is discharged from the battery device 231 as a large discharging power Bd.

[0069] Here, in the present embodiment, the generated power FC of the fuel cell power generation device 221 planned by the fuel cell output calculation unit 12 is corrected by the output correction unit 12a according to the battery SOC. And the second controller 220 controls the fuel cell power generation device 221 so as to generate the corrected generated power FC.

[0070] Specifically, as shown in Figure 4 (d) and (e) of, when the battery SOC is above the upper limit threshold during times tb1 to tb2, the output correction unit 12a corrects the generated power FC planned by the fuel cell output calculation unit 12 so as to reduce the generated power FC of the fuel cell power generation device 221. That is, the output correction unit 12a performs the first correction. In addition, the first correction is also called negative correction. In addition, the upper limit threshold is the upper limit value of the battery SOC less than 100%. As a result, as shown in Figure 4 (e) of, the second controller 220 controls the fuel cell power generation device 221 during times tb1 to tb2 so as to generate the corrected generated power FC.

[0071] On the other hand, when the battery SOC is below the lower threshold value at times tb3 to tb4, the output correction unit 12a corrects the generated power FC planned by the fuel cell output calculation unit 12 in such a way that the generated power FC of the fuel cell power generation device 221 increases. That is, the second correction is performed. In addition, the second correction is also referred to as a positive correction. Further, the lower threshold value is the lower limit value of the battery SOC greater than 0%. As a result, as shown in (e) of Figure 4 the second controller 220 controls the fuel cell power generation device 221 at times tb3 to tb4 in such a way that the corrected generated power FC is generated. In addition, at this time, the generated power FC of the fuel cell power generation device 221 is also suppressed to be below the rated output.

[0072] The control device 10 in this embodiment can be said to be a device having a memory and a controller. The memory is a recording medium that stores the power consumption D of the load 301 and the generated power PV of the solar power generation device 211 read out by the fuel cell output calculation unit 12. In addition, the recording medium is a hard disk drive, RAM, ROM, or semiconductor memory, etc. Further, the recording medium can be volatile or non-volatile. That is, the memory stores the power demand amount and the output of the solar power generation system a. In addition, the controller has the respective functions of the fuel cell output calculation unit 12 and the output correction unit 12a. That is, the controller plans the output of the fuel cell system b in such a way as to compensate for the above-mentioned difference by functioning as the fuel cell output calculation unit 12 and the output correction unit 12a. When planning this output, the controller executes at least one of the first correction and the second correction. In the first correction, when the charging rate of the battery system c is above the upper limit value less than 100%, the controller corrects the plan in such a way that the output of the fuel cell system b decreases. In the second correction, when the charging rate of the battery system c is below the lower limit value greater than 0%, the controller corrects the plan in such a way that the output of the fuel cell system b increases.

[0073] In addition, the control device 10 in this embodiment may also include the database 20 as described above. In this case, the memory may also be used as the database 20.

[0074] In addition, each component such as the data acquisition unit 11 and the controller included in the control device 10 may be configured as dedicated hardware or a circuit. Additionally, each component may also be implemented by executing a software program. That is to say, each component may also be implemented by a program execution unit such as a CPU (Central Processing Unit) or a processor reading and executing a software program recorded in a recording medium such as a hard disk or a semiconductor memory. Further, the control device 10 may be constituted by a single controller for centralized control, or may be constituted by a plurality of controllers that cooperate with each other for decentralized control.

[0075] Figure 5 It is a flowchart showing an example of the processing operation of the data acquisition unit 11.

[0076] The data acquisition unit 11 executes the processing of steps S1 to S6 for each sampling period. That is, the data acquisition unit 11 acquires a signal representing the power consumption D of the load 301 from the fourth power meter 303 (step S1). Further, the data acquisition unit 11 acquires a signal representing the generated power PV of the solar power generation device 211 from the first power meter 213 (step S2). Further, the data acquisition unit 11 acquires a signal representing the generated power FC of the fuel cell power generation device 221 from the second power meter 223 (step S3). Further, the data acquisition unit 11 acquires a signal representing the discharge power Bd or the charge power Bc of the battery device 231 from the third power meter 233 (step S4). Further, the data acquisition unit 11 acquires a signal representing the battery SOC from the third controller 230 (step S5).

[0077] Next, the data acquisition unit 11 writes the power consumption D of the load 301 represented by the signal acquired in step S1, the power of the three batteries represented by the signals acquired in steps S2 to S4, and the battery SOC represented by the signal acquired in step S5 into the database 20 (step S6). Herein, the power of the three batteries is the generated power PV of the solar power generation device 211, the generated power FC of the fuel cell power generation device 221, and the discharge power Bd or the charge power Bc of the battery device 231.

[0078] Figure 6 It is a flowchart showing an example of the processing operation of the fuel cell output calculation unit 12 and the output correction unit 12a.

[0079] The fuel cell output calculation unit 12 reads out the power consumption D of the load 301 and the generated power PV of the solar power generation device 211 at each of a plurality of measurement time points within the sampling period T1 closest to the planned time point from the database 20 (step S11).

[0080] Next, for each of the plurality of measurement time points, the fuel cell output calculation unit 12 calculates the difference between the power consumption D of the load 301 and the power generation PV of the solar power generation device 211 at that measurement time point. That is, the fuel cell output calculation unit 12 calculates the difference at that measurement time point by subtracting the power generation PV at that measurement time point from the power consumption D at that measurement time point for each of the plurality of measurement time points. Then, the fuel cell output calculation unit 12 calculates the median of the differences for each of the plurality of measurement time points as the difference value 1 (step S12). In addition, in the present embodiment, the median of the differences for each of the plurality of measurement time points is an example of the difference value 1, and the difference value 1 may also be the average of these differences.

[0081] That is, the fuel cell output calculation unit 12 in the present embodiment plans the output of the fuel cell system b in the second period in such a way that it becomes the median of the difference between the actual value of the power demand in the first period and the actual value of the output of the solar power generation system a. Alternatively, the fuel cell output calculation unit 12 plans the output of the fuel cell system b in the second period in such a way that it becomes the average of the difference between the actual value of the power demand in the first period and the actual value of the output of the solar power generation system a.

[0082] Then, the fuel cell output calculation unit 12 determines whether the difference value 1 is positive (step S13). Here, if the fuel cell output calculation unit 12 determines that the difference value 1 is positive (Yes in step S13), it sets the power generation FC of the fuel cell power generation device 221 to the difference value 1 (step S14). On the other hand, if the fuel cell output calculation unit 12 determines that the difference value 1 is not positive (No in step S13), it sets the power generation FC of the fuel cell power generation device 221 to 0 (step S15). That is, when the difference value 1 is not positive, the power generation PV of the solar power generation device 211 is equal to or greater than the power consumption D of the load 301, and the power supply to the load 301 is not insufficient, so the power generation FC of the fuel cell power generation device 221 is set to 0. In other words, the power generation FC is set in such a way that the fuel cell power generation device 221 does not output.

[0083] Here, in the present embodiment, the output correction unit 12a corrects the generated power FC set in step S14 based on the battery SOC. That is, the output correction unit 12a corrects the plan of the output of the fuel cell power generation device 221. Specifically, the output correction unit 12a acquires a signal representing the generated power FC set as the difference value 1, and further reads the latest battery SOC from the database 20 (step S14a). Then, the output correction unit 12a determines whether the battery SOC is equal to or higher than the SOC upper threshold value (step S14b). Further, the output correction unit 12a determines whether the battery SOC is equal to or lower than the SOC lower threshold value (step S14c). In addition, the SOC upper threshold value may be the same as or different from the SOC upper limit value shown in Figure 8 described later. Similarly, the SOC lower threshold value may be the same as or different from the SOC lower limit value shown in Figure 8 described later.

[0084] If the output correction unit 12a determines in step S14b that the battery SOC is equal to or higher than the SOC upper threshold value (Yes in step S14b), it sets the generated power FC of the fuel cell power generation device 221 to "difference value 1 - correction value" (step S14d). That is, the first correction as a negative correction described above is planned to be executed. On the other hand, if the output correction unit 12a determines that the battery SOC is not equal to or higher than the SOC upper threshold value (No in step S14b), it sets the generated power FC of the fuel cell power generation device 221 to the difference value 1 (step S14e).

[0085] In addition, if the output correction unit 12a determines in step S14c that the battery SOC is equal to or lower than the SOC lower threshold value (Yes in step S14c), it sets the generated power FC of the fuel cell power generation device 221 to "difference value 1 + correction value" (step S14f). That is, the second correction as a positive correction described above is planned to be executed. On the other hand, if the output correction unit 12a determines that the battery SOC is not equal to or lower than the SOC lower threshold value (No in step S14c), it sets the generated power FC of the fuel cell power generation device 221 to the difference value 1 (step S14e). Through steps S14a to S14f like this, the generated power FC of the fuel cell power generation device 221 planned by the fuel cell output calculation unit 12 is corrected.

[0086] In addition, in the case where the battery device 231 has a plurality of battery units, the above-mentioned battery SOC may also be the average value or the median value of the SOCs of these plurality of battery units.

[0087] The fuel cell output calculation unit 12 gives an instruction to the second controller 220 to generate power of the generated power FC set in step S14d, S14e, S14f, or S15 (step S16). The second controller 220 that has received such an instruction controls the fuel cell power generation device 221 and the second PCS 222. As a result, the generated power FC set in step S14d, S14e, S14f, or S15 is output from the fuel cell power generation device 221 via the second PCS 222.

[0088] Then, the fuel cell output calculation unit 12 determines whether the control period T2 has elapsed since the instruction of step S16 was performed (step S17). Here, if the fuel cell output calculation unit 12 determines that the control period T2 has not elapsed (\"No\" in step S17), the process of step S17 is repeatedly executed. On the other hand, if the fuel cell output calculation unit 12 determines that the control period T2 has elapsed (\"Yes\" in step S17), the process of step S11 is repeatedly executed. Thus, the processes of steps S11 to S17 are repeatedly executed for each control period T2.

[0089] Figure 7 It is a flowchart showing an example of the processing operation of the battery output calculation unit 13.

[0090] The battery output calculation unit 13 executes the processes of steps S21 to S27 for each of the above battery instruction cycles. Specifically, the battery output calculation unit 13 reads the latest three powers from the database 20 (step S21). The three powers are the consumption power D of the load 301, the generated power PV of the solar power generation device 211, and the generated power FC of the fuel cell power generation device 221. Then, the battery output calculation unit 13 calculates the difference between the read consumption power D of the load 301 and the generated powers PV and FC of the solar power generation device 211 and the fuel cell power generation device 221 as a difference value 2 (step S22). That is, the battery output calculation unit 13 calculates the difference value 2 by \"difference value 2 = D - PV - FC\", in other words, by subtracting the generated powers PV and FC from the consumption power D.

[0091] Next, the battery output calculation unit 13 determines whether the difference value 2 is positive (step S23). Here, if the battery output calculation unit 13 determines that the difference value 2 is positive (\"Yes\" in step S23), the discharge power indication value Bd' of the battery device 231 is set to the difference value 2 (step S24). Then, the battery output calculation unit 13 gives a discharge instruction of the discharge power indication value Bd' to the third controller 230 (step S25).

[0092] On the other hand, if the battery output calculation unit 13 determines that the difference value 2 is not a positive value ("No" in step S23), it sets the charging power indication value Bc' of the battery device 231 to the absolute value of the difference value 2 (step S26). Then, the battery output calculation unit 13 gives the charging instruction of this charging power indication value Bc' to the third controller 230 (step S27).

[0093] Figure 8 It is a flowchart showing an example of the processing operation of the third controller 230. Specifically, Figure 8 The flowchart of Figure 7 shows an example of the processing operation performed by the third controller 230 after the instruction of step S25 or S27 in the flowchart of

[0094] When the third controller 230 receives an instruction from the battery output calculation unit 13, it determines whether the instruction, that is, the indication value, is the discharge power indication value Bd' or the charging power indication value Bc' (step S31). Here, if the third controller 230 determines that the indication value is the discharge power indication value Bd' (Bd' in step S31), it determines whether the battery SOC is above the SOC lower limit value (step S32). In addition, the SOC lower limit value is a preset value, for example, stored in the third controller 230. In addition, the battery SOC being above the SOC lower limit value means that the battery SOC is greater than the SOC lower limit value. That is, in step S32, it is determined whether the battery SOC is greater than the SOC lower limit value.

[0095] Then, if the third controller 230 determines that the battery SOC is above the SOC lower limit value ("Yes" in step S32), it further determines whether the discharge power indication value Bd' exceeds the rated output of the battery device 231 (step S33). Here, if the third controller 230 determines that the discharge power indication value Bd' does not exceed the rated output ("No" in step S33), it controls the battery device 231 and the third PCS 232 so that the discharge power Bd of the battery device 231 becomes the difference value 2 (step S34). In addition, the discharge power Bd of the battery device 231 is the power discharged from the battery device 231 via the third PCS 232. That is, the battery device 231 discharges the difference value 2 via the third PCS 232.

[0096] On the other hand, if the 3rd controller 230 determines that the discharge power indication value Bd’ has exceeded the rated output (Yes in step S33), it controls the battery device 231 and the 3rd PCS 232 in such a way that the discharge power Bd of the battery device 231 becomes the rated output (step S35). That is, the battery device 231 discharges at the rated output via the 3rd PCS 232. In addition, if the 3rd controller 230 determines that the battery SOC is not above the SOC lower limit value (No in step S32), it controls the battery device 231 and the 3rd PCS 232 in such a way that the discharge power Bd of the battery device 231 becomes 0 (step S36). That is, the battery device 231 does not discharge.

[0097] In addition, if it is determined in step S31 that the indication value is the charge power indication value Bc’ (Bc’ in step S31), the 3rd controller 230 determines whether the battery SOC is below the SOC upper limit value (step S37). In addition, the SOC upper limit value is a preset value, for example, stored in the 3rd controller 230. In addition, the battery SOC being below the SOC upper limit value means that the battery SOC is less than the SOC upper limit value. That is, in step S37, it is determined whether the battery SOC is less than the SOC upper limit value.

[0098] Then, if the 3rd controller 230 determines that the battery SOC is below the SOC upper limit value (Yes in step S37), it further determines whether the charge power indication value Bc’ has exceeded the rated output of the battery device 231 (step S38). Here, if the 3rd controller 230 determines that the charge power indication value Bc’ has not exceeded the rated output (No in step S38), it controls the battery device 231 and the 3rd PCS 232 in such a way that the charge power Bc of the battery device 231 becomes the absolute value of the difference value 2 (step S39). In addition, the charge power Bc of the battery device 231 is the power charged into the battery device 231 via the 3rd PCS 232. That is, the battery device 231 charges by the absolute value of the difference value 2.

[0099] On the other hand, if the third controller 230 determines that the charging power indication value Bc' exceeds the rated output ("Yes" in step S38), the battery device 231 and the third PCS 232 are controlled in such a way that the charging power Bc of the battery device 231 becomes the rated output (step S40). In other words, the battery device 231 is charged to the rated output. In addition, if the third controller 230 determines that the battery SOC is not lower than the SOC upper limit value ("No" in step S37), the battery device 231 and the third PCS 232 are controlled in such a way that the charging power Bc of the battery device 231 becomes 0 (step S41). In other words, the battery device 231 is not charged.

[0100] In addition, when the battery device 231 is composed of a plurality of battery cells, the third controller 230 may also execute the control for each battery cell. Figure 8 In this case, the discharge power indication value Bd′ and the charge power indication value Bc′ used in each battery unit may be values ​​obtained by dividing the indication value of the entire battery device 231 by the number of battery units included in the battery device 231.

[0101] In addition, in the present embodiment, the third controller 230 has a function of controlling the discharge power Bd and the charge power Bc of the storage battery device 231 based on the charge power indication value Bc' and the discharge power indication value Bd'. However, the storage battery output calculation unit 13 of the control device 10 may also have this function. In other words, the storage battery output calculation unit 13 may also perform Figure 8 In this case, the battery output calculation unit 13 performs the following steps. Figure 7 In step S21, the latest battery SOC is further read from the database 20. Figure 8 The read battery SOC is used in steps S32 and S37. On the other hand, the third controller 230 controls the battery device 231 and the third PCS 232 according to the discharge power Bd and the charge power Bc determined by the battery output calculation unit 13 in the processing of steps S34 to S36 and S39 to S41.

[0102] Figure 9 1 is a diagram showing an example of the effect obtained by the operation mode of the control device 10 in this embodiment. Figure 9 In the embodiment, the effect obtained by the operation mode of the control device 10 is shown in comparison with the operation mode of the comparative example. Specifically, Figure 9 (a) is a graph showing the time transition of the battery SOC obtained by the operation mode of the comparative example, Figure 9(b) is a graph showing the time course of the battery SOC obtained from the operation mode of the control device 10 in the present embodiment. The vertical axis of each graph represents the battery SOC, and the horizontal axis represents the month and day.

[0103] In the operation mode of the comparative example, the generated power FC of the fuel cell power generation device 221 planned by the fuel cell output calculation unit 12 is not corrected. That is, the generated power FC set to the difference value 1 in Figure 6 step S14 is instructed to the second controller 220 regardless of the battery SOC.

[0104] In such an operation mode of the comparative example, as Figure 9 (a) shows, there is a tendency for the battery SOC to be maintained around 100% from the end of August.

[0105] On the other hand, in the operation mode of the control device 10 in the present embodiment, as Figure 9 (b) shows, even after the end of August, the battery SOC is suppressed to approximately 80% or less. In addition, the battery SOC is maintained at approximately 20% or more.

[0106] In addition, in the power system 200 to which each operation mode is applied, the solar power generation device 211 includes 1800 solar power generation panels, and the maximum output of the entire solar power generation device 211 is 500 kW. The fuel cell power generation device 221 includes 100 hydrogen fuel cells, and the maximum output or rated output of the entire fuel cell power generation device 221 is 500 kW. In addition, the hydrogen fuel cell is also referred to as a fuel cell stack device. In addition, the control range of the fuel cell power generation device 221 is from the rated output to 0 kW. In addition, the maximum output of each hydrogen fuel cell is 5 kW. And the control period T2 is 1 hour. The maximum output or rated output of the battery device 231 is 300 kW, and the capacity of the battery device 231 is 1000 kWh. In addition, in the operation mode of the control device 10 in the present embodiment, the correction value used in the correction of the generated power FC of the fuel cell power generation device 221 is 50 kW.

[0107] As described above, in the present embodiment, the output of the fuel cell system b is planned so as to compensate for the difference between the power demand and the output of the solar power generation system a. Here, at least one of the first correction and the second correction is performed on this plan. In the first correction, when the charging rate of the battery system c is equal to or higher than the upper limit value less than 100%, the plan is corrected so as to reduce the output of the fuel cell system b. In the second correction, when the charging rate of the battery system c is equal to or lower than the lower limit value greater than 0%, the plan is corrected so as to increase the output of the fuel cell system b.

[0108] Thus, when the first correction is executed, the battery system c can be discharged in such a way as to make up for the insufficient power with respect to the power demand due to the decrease in the output of the fuel cell system b. Therefore, the possibility that the battery system c becomes, for example, a fully charged state and the surplus power of the solar power generation system a flows back to the power organization 100 is reduced. In addition, when the second correction is executed, the discharge from the battery system c is reduced due to the increase in the output of the fuel cell system b. Therefore, the possibility that the battery system c becomes, for example, a fully discharged state and power is purchased from the power organization 100 is reduced. In addition, since the possibility that the battery system c becomes fully charged or fully discharged is reduced, the possibility of extending the life of the battery is increased.

[0109] In addition, in the case where the battery system c includes a plurality of battery units, the charging rate of the battery system c may also be the average value or the median value of the charging rates of these plurality of battery units. In addition, each of the power demand amount and the output of the solar power generation system a may be an actual value or a predicted value. When each of the power demand amount and the output of the solar power generation system a is an actual value, the charging rate of the battery system c may be the charging rate at the planned time point of the output of the battery system c. In addition, when each of the power demand amount and the output of the solar power generation system a is a predicted value, the charging rate of the battery system c may also be a predicted value. That is, each of the power consumption D and the power generation PV is an actual value stored in the database 20, but may also be a predicted value. In the case where each of the power consumption D and the power generation PV is a predicted value, the battery SOC used in the planned correction may also be a predicted value instead of the actual value stored in the database 20.

[0110] In addition, in the present embodiment, the output of the fuel cell system b in the second period, which is a control period T2 later than the first period, is planned in such a way as to make up for the difference between the actual value of the power demand amount in the first period, which is the sampling period T1, and the actual value of the output of the solar power generation system a. Further, when the fuel cell system b is generating power at the planned output in the second period, when the sum of the output of the solar power generation system a and the output of the fuel cell system b is greater than the power demand amount, charging is performed through the battery system c. On the other hand, when the fuel cell system b is generating power at the planned output in the second period, when the sum of the output of the solar power generation system a and the output of the fuel cell system b is less than the power demand amount, discharge is performed through the battery system c in such a way as to satisfy the power demand amount.

[0111] Accordingly, compared with the case where the output of the battery system c is planned in such a way as to make up for the difference between the actual value of the power demand during the first period of the sampling period T1 and the actual value of the output of the solar power generation system a, the power demand can be further satisfied by using the power of the power system 200. The background is as follows: the battery system c has excellent load following performance compared with the fuel cell system b. On the other hand, the fuel cell system b has a larger power storage capacity compared with the battery system c. In view of this background, in the present embodiment, for the difference between the power demand and the solar power generation amount during the second period of the control period T2, the fuel cell system b is planned to make up for the power as a basic power source, and for the temporary difference that cannot be completely made up, the power of the battery system c with excellent load following performance is used to make up for it. As a result, it becomes a form that complements the above-mentioned advantages and disadvantages of the fuel cell system b and the battery system c, and the power demand of the load can be further satisfied by using the power of the power system 200. That is to say, according to the present embodiment, the power purchase from the power organization 100 for satisfying the power demand of the load is reduced.

[0112] In addition, in the present embodiment, as Figure 2 shown, the actual value during a short period such as the sampling period T1 is used to plan the output of the fuel cell power generation device 221 during a long period such as the subsequent control period T2.

[0113] Accordingly, compared with the case where the output of the fuel cell system is planned using the actual value during the first period longer than the second period for the second period, the deviation of the output of the fuel cell system from the difference between the power demand of the load and the output of the solar power generation system a during the second period is suppressed. This is because: compared with the case where the output of the fuel cell system b during the second period is planned using the actual value during the first period longer than the second period, the output of the fuel cell system b is planned by only considering the actual value of the period closer to the second period. Furthermore, since the output of the fuel cell power generation device 221 during this long period is maintained constant, the deterioration of the fuel cell power generation device 221 can be further suppressed.

[0114] In addition, in the present embodiment, as Figure 6 in step S12, the median of the difference is used. Therefore, in the case where the actual value during the first period continues during the second period, the output of the fuel cell power generation device 221 can be used to appropriately make up for the difference between the power demand during the second period and the output of the solar power generation device 211. As a result, the charge and discharge of the battery device 231 can be suppressed.

[0115] Alternatively, in the present embodiment, in Figure 6In step S12, even if the average value of the difference is used instead of the median value of the difference, the output of the fuel cell power generation device 221 can be used to appropriately compensate for the difference between the power demand during the second period and the output of the solar power generation device 211. As a result, charging and discharging of the battery device 231 can be suppressed.

[0116] As described above, the operation method of the power system 200 and the control device 10 of the present disclosure have been described based on the above-described embodiment. However, the present disclosure is not limited to this embodiment. As long as it does not deviate from the gist of the present disclosure, technical solutions obtained by applying various modifications conceived by those skilled in the art to the above-described embodiment are also included in the present disclosure.

[0117] For example, in the above-described embodiment, the control device 10 communicates with the database 20, the power system 200, and the fourth power meter 303 via a communication line. However, this communication is not limited to wired communication and may also be wireless communication. The wireless communication can be performed via Wi-Fi (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), or specific low-power wireless.

[0118] In addition, in the above-described embodiment, each component can be configured by dedicated hardware or can be implemented by executing a software program suitable for each component. Each component can be implemented by a program execution unit such as a CPU or a processor reading and executing a software program recorded in a recording medium such as a hard disk or a semiconductor memory. Here, the software for implementing the control device 10 and the power system 200 of the above-described embodiment is a computer program that causes a computer to execute Figures 5 to 8 each step of the flowcharts shown respectively.

[0119] In addition, the following cases are also included in the present disclosure.

[0120] (1) At least one of the above-described devices, specifically, a computer system including a microprocessor, a ROM, a RAM, a hard disk unit, a display unit, a keyboard, a mouse, etc. A computer program is stored in the RAM or the hard disk unit. By operating the microprocessor according to the computer program, at least one of the above-described devices realizes its function. Here, in order to realize a predetermined function, the computer program is constituted by combining a plurality of command codes indicating instructions to the computer.

[0121] (2) Part or all of the components constituting the above-described at least one device may also be constituted by a single system LSI (Large Scale Integration). A system LSI is a super-multi-functional LSI manufactured by integrating multiple components on a single chip. Specifically, it is configured to include a computer system such as a microprocessor, ROM, and RAM. In the RAM, a computer program is stored. By operating the microprocessor according to the computer program, the system LSI realizes its functions.

[0122] (3) Part or all of the components constituting the above-described at least one device may also be constituted by an IC card or a single module that can be attached to and detached from the device. The IC card or module is a computer system constituted by a microprocessor, ROM, RAM, etc. The IC card or module may also include the above-described super-multi-functional LSI. By operating the microprocessor according to the computer program, the IC card or module realizes its functions. The IC card or the module may have anti-tampering properties.

[0123] (4) The present disclosure may also be the method shown above. Additionally, it may be a computer program for implementing these methods by a computer, or may also be a digital signal constituted by a computer program.

[0124] Furthermore, the present disclosure may also be a device obtained by recording a computer program or a digital signal on a computer-readable recording medium such as a flexible disk, hard disk, CD (Compact Disc)-ROM, DVD, DVD-ROM, DVD-RAM, BD (Blu-ray (registered trademark) Disc), semiconductor memory, etc. Additionally, it may also be a digital signal recorded in these recording media.

[0125] Furthermore, the present disclosure may also be a device for transmitting a computer program or a digital signal via an electrical communication line, wireless or wired communication line, a network represented by the Internet, data broadcasting, etc.

[0126] Additionally, it may also be implemented using an independent other computer system by recording a program or a digital signal on a recording medium and transmitting it, or by transmitting a program or a digital signal via a network or the like.

[0127] Industrial Applicability

[0128] The operation method of the power system of the present disclosure can be applied to, for example, devices or systems for controlling solar power generation systems, fuel cell systems, and battery systems.

[0129] Explanation of Reference Numerals

[0130] 10 Control Device

[0131] 11 Data acquisition unit

[0132] 12 Fuel cell output calculation unit

[0133] 13 Battery output calculation unit

[0134] 20 Database

[0135] 100 Power organization

[0136] 200 Power system

[0137] 210 First controller

[0138] 211 Solar power generation device

[0139] 212 First PCS

[0140] 213 First power meter

[0141] 220 Second controller

[0142] 221 Fuel cell power generation device

[0143] 222 Second PCS

[0144] 223 Second power meter

[0145] 230 Third controller

[0146] 231 Battery device

[0147] 232 Third PCS

[0148] 233 Third power meter

[0149] 301 Load

[0150] 303 Fourth power meter

[0151] a Solar power generation system

[0152] b Fuel cell system

[0153] c Battery system

[0154] T1 Sampling period (first period)

[0155] T2 Control period (second period)

Claims

1. A method for operating a power system, comprising: a step of planning the output of a fuel cell system in a manner that compensates for the difference between the power demand and the output of a solar power generation system, wherein, in the step, at least one of a first correction and a second correction is performed. The first correction is a correction for correcting the plan in a manner that reduces the output of the fuel cell system when the charge rate of a battery system is equal to or higher than an upper limit value less than 100%. The second correction is a correction for correcting the plan in a manner that increases the output of the fuel cell system when the charge rate of the battery system is equal to or lower than a lower limit value greater than 0%.

2. A control device for a power system, comprising: a memory that stores the power demand and the output of a solar power generation system; and a controller that, when planning the output of a fuel cell system in a manner that compensates for the difference between the power demand and the output of the solar power generation system, performs at least one of a first correction and a second correction. The first correction is a correction for correcting the plan in a manner that reduces the output of the fuel cell system when the charge rate of a battery system is equal to or higher than an upper limit value less than 100%. The second correction is a correction for correcting the plan in a manner that increases the output of the fuel cell system when the charge rate of the battery system is equal to or lower than a lower limit value greater than 0%.

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