Power Control Method

Abstract

The power control method disclosed herein determines the supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than the power demand of the power consumer when power is supplied to the power load of a power consumer from a distributed power generation system including a distributed power generation device and a power storage device.

Description

[Technical field]

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

[0002] There have been various proposals for power control of distributed power supply systems. For example, Patent Document 1 describes controlling the output of a fuel cell so that it matches the difference between the power demand and the output of a photovoltaic power generation device, and absorbing the excess or shortage of power supply relative to the power demand caused by the delay in the output fluctuation of the fuel cell by charging and discharging a storage battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-208426 A 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 distributed power system that can reduce the possibility of power from a distributed power system flowing back into a power grid more than ever before. [Means for solving the problem]

[0005] In order to solve the above problems, a power control method of one aspect of the present disclosure determines the supply power of the distributed power generation device using a first coefficient when supplying power to a power load of a power consumer from a distributed power generation system including a distributed power generation device and a power storage device, so that the supply power of the distributed power generation device is smaller than the power demand of the power consumer.

[0006] A power control device of one embodiment of the present disclosure includes a memory device that stores the power demand of a power consumer, and a controller that determines the supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than the demand power of the power consumer when supplying power to a power load of the power consumer from a distributed power source system including a distributed power generation device and a power storage device.

[0007] A distributed power supply system according to one aspect of the present disclosure includes a distributed power generation 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 distributed power system according to one aspect of the present disclosure have the advantage of being able to reduce the possibility of power from the distributed power system flowing back into the power grid more than ever before. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating an example of a distributed power supply system according to a first embodiment. [Diagram 2] FIG. 2 is a diagram illustrating an example of the power control device according to the first embodiment. [Diagram 3] FIG. 3 is a flowchart showing an example of the operation (power control method) of the power control device of the first embodiment. [Figure 4A] FIG. 4A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a first example of the first embodiment. [Figure 4B] FIG. 4B is a flowchart showing an example of the operation of the power control device (power control method) in the first example of the first embodiment. [Figure 5A] FIG. 5A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a second example of the first embodiment. [Figure 5B] FIG. 5B is a flowchart showing an example of the operation of the power control device (power control method) in the second example of the first embodiment. [Figure 6A]FIG. 6A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a third example of the first embodiment. [Figure 6B] FIG. 6B is a flowchart showing an example of the operation of the power control device (power control method) in the third example of the first embodiment. [Figure 7A] FIG. 7A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a fourth example of the first embodiment. [Figure 7B] FIG. 7B is a flowchart showing an example of the operation of the power control device (power control method) in the fourth example of the first embodiment. [Figure 8A] FIG. 8A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fifth example of the first embodiment. [Figure 8B] FIG. 8B is a flowchart showing an example of the operation of the power control device (power control method) in the fifth example of the first embodiment. [Figure 9A] FIG. 9A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a sixth example of the first embodiment. [Figure 9B] FIG. 9B is a flowchart showing an example of the operation of the power control device (power control method) in the sixth example of the first embodiment. [Figure 10A] FIG. 10A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a seventh example of the first embodiment. [Figure 10B] FIG. 10B is a flowchart showing an example of the operation of the power control device (power control method) in the seventh embodiment of the first embodiment. [Figure 11A] FIG. 11A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to an eighth example of the first embodiment. [Figure 11B] FIG. 11B is a flowchart showing an example of the operation of the power control device (power control method) in the eighth embodiment of the first embodiment. [Figure 12A]FIG. 12A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to an eleventh example of the first embodiment. [Figure 12B] FIG. 12B is a flowchart showing an example of the operation of the power control device (power control method) in the eleventh embodiment of the first embodiment. [Figure 13A] FIG. 13A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a twelfth example of the first embodiment. [Figure 13B] FIG. 13B is a flowchart showing an example of the operation of the power control device (power control method) in the twelfth embodiment of the first embodiment. [Figure 14A] FIG. 14A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a thirteenth example of the first embodiment. [Figure 14B] FIG. 14B is a flowchart showing an example of the operation of the power control device (power control method) in the thirteenth embodiment of the first embodiment. [Figure 15A] FIG. 15A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fourteenth example of the first embodiment. [Figure 15B] FIG. 15B is a flowchart showing an example of the operation of the power control device (power control method) in the fourteenth embodiment of the first embodiment. [Figure 16A] FIG. 16A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fifteenth example of the first embodiment. [Figure 16B] FIG. 16B is a flowchart showing an example of the operation of the power control device (power control method) in the fifteenth embodiment of the first embodiment. [Figure 17A] FIG. 17A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a sixteenth example of the first embodiment. [Figure 17B] FIG. 17B is a flowchart showing an example of the operation of the power control device (power control method) in the 16th embodiment of the first aspect. [Figure 18]FIG. 18 is a diagram illustrating an example of a distributed power supply system according to the second embodiment. [Figure 19A] FIG. 19A is a flowchart showing an example of the operation for determining the power generation power of the fuel cell device by the power control device of the second embodiment. [Figure 19B] FIG. 19B is a flowchart showing an example of the operation for determining the power generation power of the fuel cell device by the power control device of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Paragraph

[0037] of Patent Document 1 discloses that when excess power generation occurs due to a load reduction or an increase in power generation, a control command is issued to reduce the fuel cell output to the required fuel cell output current calculated from the solar cell output current and the load current, and since there is a time delay before the actual output reduction occurs, power control is performed to charge a storage device.

[0011] However, the invention described in Patent Document 1 does not fully consider the prevention of reverse power flow from the fuel cell to the power grid. For example, when the power storage device is fully charged or close to it, a time delay in the change in the output of the fuel cell may cause a reverse power flow from the fuel cell to the power grid.

[0012] Therefore, in the power control method of the first aspect of the present disclosure, when power is supplied to a power load of a power consumer from a distributed power generation system including a distributed power generation device and a power storage device, the supply power of the distributed power generation device is determined using a first coefficient so that the supply power of the distributed power generation device is smaller than the power demand of the power consumer.

[0013] According to the above, the power control method of the present aspect can reduce the possibility of power from the distributed power supply system flowing back into the power grid more than ever before.

[0014] Specifically, the power control method of this aspect increases the possibility of power purchase from the power grid, but allows this and determines the supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than the demand power of the power consumer. As a result, the power control method of this aspect can appropriately suppress the power of the distributed power supply system from flowing back to the power grid, compared to a case in which the supply power of the distributed power generation device is not determined using the first coefficient.

[0015] A second aspect of the power control method of the present disclosure is the power control method of the first aspect, wherein the distributed power generation device includes a solar power generation device and a fuel cell device, and a planned value of the power generation power of the fuel cell device is determined so as to satisfy the difference between the predicted value or actual power demand of the power consumer multiplied by a first coefficient α and reduced by the value, and the predicted value or actual power generation power of the solar power generation device.

[0016] The generated power of the fuel cell device calculated from the difference between the predicted value or actual demand power of the power consumer multiplied by a first coefficient α and reduced, and the predicted value or actual generated power of the solar power generation device (hereinafter referred to as the generated power of this embodiment) is smaller than the generated power of the fuel cell device calculated from the difference between the predicted value or actual demand power of the power consumer and the predicted value or actual generated power of the solar power generation device (hereinafter referred to as the generated power of the comparative example).

[0017] Here, the "power generated in the comparative example" corresponds to power that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid. In other words, the "power generated in this embodiment" is power that is further reduced by using the first coefficient α from the power that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid.

[0018] Therefore, in the power control method of this embodiment, the planned value of the generated power of the fuel cell device is determined so as to satisfy the difference between the value obtained by multiplying the predicted value or actual demand power of the power consumer by the first coefficient α and reducing it, and the predicted value or actual generated power of the solar power generation device, thereby appropriately suppressing the generated power of the fuel cell device from flowing back into the power grid, compared to a case in which the planned value of the generated power of the fuel cell device is determined without reducing the predicted value or actual demand power of the power consumer.

[0019] A third aspect of the power control method of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a solar power generation device and a fuel cell device, and the generated power of the fuel cell device may be determined as a value obtained by adding a planned value of the generated power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer, the actual generated power of the solar power generation device, and the planned value of the generated power of the fuel cell device, and reducing the sum by a first coefficient β.

[0020] In the case where the distributed power generation device includes a solar power generation device and a fuel cell device, the sum of the planned value of the power generation power of the fuel cell device and the correction value of the planned value corresponds to the power generation power of the fuel cell device that is unlikely to induce reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the combined power of the planned value and the correction value of the planned value by the first coefficient β and reducing it is the power further reduced by using the first coefficient β from the power generation power that is unlikely to induce reverse power flow from the distributed power generation device to the power grid.

[0021] Therefore, in the power control method of the present embodiment, by determining the power generation power of the fuel cell device as a value obtained by adding a correction value for the planned value of the power generation power of the fuel cell device to the first coefficient β, the power generation power of the fuel cell device can be appropriately prevented from flowing back into the power grid, compared to when the power generation power of the fuel cell device is determined without multiplying it by the first coefficient β.

[0022] A fourth aspect of the power control method of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a fuel cell device, and the power generation power of the fuel cell device may be determined as a value obtained by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation power of the fuel cell device, and reducing the sum by multiplying the sum by a first coefficient β.

[0023] In the case where the distributed power generation device includes a fuel cell device, the value obtained by adding the correction value of the planned value to the planned value of the power generation of the fuel cell device corresponds to the power generation of the fuel cell device that is unlikely to induce reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the combined power of the planned value and the correction value of the planned value by the first coefficient β and reducing it is the power further reduced by using the first coefficient β from the power generation of the distributed power generation device that is unlikely to induce reverse power flow to the power grid.

[0024] Therefore, in the power control method of the present embodiment, by determining the generated power of the fuel cell device as the value obtained by adding a correction value for the planned value of the generated power of the fuel cell device to the planned value, multiplying the result by the first coefficient β and reducing it, the method can appropriately suppress the generated power of the fuel cell device from flowing back into the power grid, compared to when the generated power of the fuel cell device is determined without multiplying by the first coefficient β.

[0025] A fifth aspect of the power control method of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a solar power generation device and a fuel cell device, and the upper power generation limit value of the solar power generation device may be determined to be a value obtained by multiplying a value less than the difference between the sum of the actual demand power of the power consumer and the chargeable power less than the maximum charging power of the storage device and the actual power generation power of the fuel cell device, and reducing the value by a first coefficient γ.

[0026] In the case where the distributed power generation device includes a solar power generation device and a fuel cell device, a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device, and the actual power generation power of the fuel cell device corresponds to the power generation power of the solar power generation device that is unlikely to induce reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the value equal to or less than the difference by the first coefficient γ is the power further reduced by using the first coefficient β from the power generation power that is unlikely to induce reverse power flow from the distributed power generation device to the power grid.

[0027] Therefore, in the power control method of this embodiment, by determining the power generation upper limit value of the solar power generation device as a value obtained by multiplying a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device, and the actual power generation power of the fuel cell device, by the first coefficient γ and reducing the result, the power generation upper limit value of the solar power generation device can be appropriately suppressed from flowing back into the power grid, compared to a case in which the power generation upper limit value of the solar power generation device is determined without reducing the value equal to or less than the difference.

[0028] A power control method of a sixth aspect of the present disclosure is the power control method of the first or second aspect, wherein the distributed power generation device includes a solar power generation device, and the power generation upper limit value of the solar power generation device may be determined to be a value obtained by multiplying a value less than the sum of the actual demand power of the power consumer and the chargeable power less than the maximum charging power of the storage device by a first coefficient γ and reducing the value.

[0029] In the case where the distributed power generation device includes a solar power generation device, a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device corresponds to the power generated by the solar power generation device that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the value equal to or less than the sum by the first coefficient γ is the power further reduced by using the first coefficient γ from the power generated by the distributed power generation device that is unlikely to induce a reverse power flow to the power grid.

[0030] Therefore, in the power control method of this embodiment, by determining the power generation upper limit value of the solar power generation device as a value obtained by multiplying a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device by the first coefficient γ and reducing the result, the power generation upper limit value of the solar power generation device can be appropriately prevented from flowing back into the power grid, compared to a case in which the power generation upper limit value of the solar power generation device is determined without reducing the value equal to or less than the sum.

[0031] A seventh aspect of the power control method of the present disclosure is the power control method of the first or second aspect, wherein the distributed power generation device includes a solar power generation device and a fuel cell device, and the charge power or discharge power of the power storage device may be determined to be a value obtained by multiplying a difference between an actual power demand of the power consumer and a sum of an actual power generated by the solar power generation device and an actual power generated by the fuel cell device by a second coefficient δ and reducing the result.

[0032] In the case where the distributed power generation device includes a solar power generation device and a fuel cell device, the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation device and the actual power generated by the fuel cell device corresponds to the charging power or discharging power of the power storage device that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ and reducing it is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid.

[0033] Therefore, in the power control method of this embodiment, by multiplying the difference between the actual demand power of the power consumer and the sum of the actual generated power of the solar power generation device and the actual generated power of the fuel cell device by the second coefficient δ and reducing the result to determine the charging power or discharging power of the power storage device, the method can appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to a case in which the charging power or discharging power of the power storage device is determined without reducing the difference.

[0034] A power control method of an eighth aspect of the present disclosure is the power control method of the first or second aspect, wherein the distributed power generation device includes a solar power generation device, and a value obtained by multiplying a difference between an actual power demand of the power consumer and an actual power generation power of the solar power generation device by a second coefficient δ and reducing the result may be determined as the charging power or discharging power of the power storage device.

[0035] In the case where the distributed power generation device includes a solar power generation device, the difference between the actual power demand of the power consumer and the actual power generation by the solar power generation device corresponds to the charging power or discharging power of the power storage device that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ and reducing it is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid.

[0036] Therefore, in the power control method of this embodiment, by multiplying the difference between the actual power demand of the power consumer and the actual power generated by the solar power generation device by the second coefficient δ and reducing the result to determine the charging power or discharging power of the power storage device, the method can appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to a case in which the charging power or discharging power of the power storage device is determined without reducing the difference.

[0037] A ninth aspect of the power control method of the present disclosure is the power control method of the first or second aspect, wherein the distributed power generation device includes a fuel cell device, and the charge power or discharge power of the power storage device may be determined to be a value obtained by multiplying a difference between an actual demand power of the power consumer and an actual generated power of the fuel cell device by a second coefficient δ and reducing the result.

[0038] In the case where the distributed power generation device includes a fuel cell device, the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell device corresponds to the charging power or discharging power of the power storage device that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation device to the power grid.

[0039] Therefore, in the power control method of this embodiment, by multiplying the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell device by the second coefficient δ and reducing the result to determine the charging power or discharging power of the power storage device, the method can appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to a case in which the charging power or discharging power of the power storage device is determined without reducing the difference.

[0040] A power control method according to a tenth aspect of the present disclosure is the power control method according to any one of the first to sixth aspects, wherein the first coefficient may vary depending on the season.

[0041] In general, the power generated by a photovoltaic power generation device and the power demand of a power consumer change according to the season. Therefore, the power control method of this embodiment can reduce the amount of power flowing back from the distributed power generation device to the power grid by setting the first coefficient to a desired value according to the season, compared to the case where the first coefficient is constant for each season.

[0042] A power control method according to an eleventh aspect of the present disclosure is the power control method according to any one of the seventh to ninth aspects, wherein the second coefficient may vary depending on the season.

[0043] In general, the power generated by a photovoltaic power generation device and the power demand of a power consumer change according to the season. Therefore, the power control method of this embodiment can reduce the amount of power flowing back from the distributed power generation device to the power grid by setting the second coefficient to a desired value according to the season, compared to the case where the second coefficient is constant for each season.

[0044] A power control method of a twelfth aspect of the present disclosure is the power control method of the first or second aspect, wherein the distributed power generation device includes a solar power generation device and a fuel cell device, and executes a first control in which the generated power of the fuel cell device is determined as the generated power of the fuel cell device by multiplying the sum of a planned value of the generated power of the fuel cell device and an actual demand power of the power consumer, the actual generated power of the solar power generation device, and a correction value of the planned value based on the planned value of the generated power of the fuel cell device, and multiplying the sum by a first coefficient β, or executes a second control in which the charge power or discharge power of the power storage device is determined as the charge power or discharge power of the power storage device by multiplying the difference between the actual demand power of the power consumer and the sum of the actual generated power of the solar power generation device and the actual generated power of the fuel cell device by a second coefficient δ, and the first coefficient β may be smaller than the second coefficient δ.

[0045] As described above, in the power control method of this embodiment, a first control is executed in which the power generation power of the fuel cell device is determined by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value, multiplying the result by a first coefficient β, and reducing the sum. As a result, the power generation power of the fuel cell device can be appropriately prevented from flowing back into the power grid, compared to when control is executed in which the power generation power of the fuel cell device is determined without multiplying by the first coefficient β.

[0046] Furthermore, as described above, the power control method of this embodiment executes a second control in which the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation device and the actual power generated by the fuel cell device is multiplied by the second coefficient δ and reduced to determine the charging power or discharging power of the power storage device. This makes it possible to appropriately suppress reverse flow of the supply power of the distributed power generation device to the power grid, compared to a case in which control is executed to determine the charging power or discharging power of the power storage device without reducing the difference.

[0047] Here, if the first and second coefficients are equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device to the power grid in the first control is likely to be greater than the effect of the second control in the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device, and the remaining part is covered by the charging power or discharging power of the power storage device, and as a result, the power generated by the fuel cell device tends to be greater than the charging power or discharging power of the power storage device.

[0048] Therefore, by making the first coefficient β in the first control smaller than the second coefficient δ in the second control, as in the power control method of this embodiment, it is possible to appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0049] A power control method of a thirteenth aspect of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a fuel cell device, and a first control is performed in which the generated power of the fuel cell device is determined to be a value obtained by multiplying a first coefficient β by adding a planned value of the generated power of the fuel cell device to a correction value of the planned value based on the actual demand power of the power consumer and the planned value of the generated power of the fuel cell device, and reducing the value, or a second control is performed in which the charging power or discharging power of the power storage device is determined to be a value obtained by multiplying a difference between the actual demand power of the power consumer and the actual generated power of the fuel cell device by a second coefficient δ, and reducing the value, wherein the first coefficient β may be smaller than the second coefficient δ.

[0050] As described above, in the power control method of this embodiment, a first control is executed in which the power generation power of the fuel cell device is determined by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value, multiplying the result by a first coefficient β, and reducing the sum. As a result, the power generation power of the fuel cell device can be appropriately prevented from flowing back into the power grid, compared to when control is executed in which the power generation power of the fuel cell device is determined without multiplying by the first coefficient β.

[0051] Furthermore, as described above, the power control method of this embodiment executes a second control in which the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell device is multiplied by the second coefficient δ and the reduced value is determined as the charging power or discharging power of the power storage device, thereby making it possible to appropriately suppress reverse flow of the supply power of the distributed power generation device to the power grid, compared to a case in which control is executed in which the charging power or discharging power of the power storage device is determined without reducing the difference.

[0052] Here, if the first and second coefficients are equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device to the power grid in the first control is likely to be greater than the effect of the second control in the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device, and the remaining part is covered by the charging power or discharging power of the power storage device, and as a result, the power generated by the fuel cell device tends to be greater than the charging power or discharging power of the power storage device.

[0053] Therefore, in the power control method of this embodiment, by making the first coefficient β in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0054] A power control method of a fourteenth aspect of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a solar power generation device and a fuel cell device, and executes a first control in which a value less than the difference between the sum of the actual power demand of the power consumer and the chargeable power less than the maximum charging power of the power storage device and the actual generated power of the fuel cell device is multiplied by a first coefficient γ to determine the upper power generation limit value of the solar power generation device, or a second control in which a value less than the difference between the actual power demand of the power consumer and the sum of the actual generated power of the solar power generation device and the actual generated power of the fuel cell device is multiplied by a second coefficient δ to determine the charging power or discharging power of the power storage device, and the first coefficient γ may be smaller than the second coefficient δ.

[0055] As described above, in the power control method of this embodiment, a first control is executed in which a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device, and the actual power generation power of the fuel cell device, is multiplied by a first coefficient γ and reduced, to determine the power generation upper limit value of the solar power generation device. This makes it possible to appropriately suppress reverse flow of power generated by the solar power generation device to the power grid, compared to a case in which control is executed in which the power generation upper limit value of the solar power generation device is determined without reducing a value equal to or less than the difference.

[0056] Furthermore, as described above, the power control method of this embodiment executes a second control in which the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation device and the actual power generated by the fuel cell device is multiplied by the second coefficient δ and reduced to determine the charging power or discharging power of the power storage device. This makes it possible to appropriately suppress reverse flow of the supply power of the distributed power generation device to the power grid, compared to a case in which control is executed to determine the charging power or discharging power of the power storage device without reducing the difference.

[0057] Here, if the first and second coefficients are equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device to the power grid in the first control is likely to be greater than the effect of the second control in the latter control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device, and the remaining part is covered by the charging power or discharging power of the power storage device, and as a result, the power generated by the photovoltaic power generation device tends to be greater than the charging power or discharging power of the power storage device.

[0058] Therefore, in the power control method of this embodiment, by making the first coefficient γ in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0059] A power control method of a fifteenth aspect of the present disclosure is a power control method of the first or second aspect, in which the distributed power generation device includes a solar power generation device, and executes a first control in which a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device is multiplied by a first coefficient γ and reduced to determine the upper power generation limit value of the solar power generation device, or a second control in which a value equal to or less than the difference between the actual power demand of the power consumer and the actual power generation power of the solar power generation device is multiplied by a second coefficient δ and reduced to determine the charging power or discharging power of the power storage device, wherein the first coefficient γ may be smaller than the second coefficient δ.

[0060] As described above, in the power control method of this embodiment, a first control is executed in which a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device is multiplied by a first coefficient γ and reduced to determine the power generation upper limit value of the solar power generation device. This makes it possible to appropriately suppress reverse flow of power generated by the solar power generation device to the power grid, compared to a case in which control is executed in which a value equal to or less than the sum is determined to be the power generation upper limit value of the solar power generation device without reducing it.

[0061] Furthermore, as described above, the power control method of this embodiment executes a second control in which the difference between the actual power demand of the power consumer and the actual power generated by the solar power generation device is multiplied by the second coefficient δ and the reduced value is determined as the charging power or discharging power of the power storage device. This makes it possible to appropriately suppress reverse flow of the supply power of the distributed power generation device to the power grid, compared to the case in which control is executed to determine the charging power or discharging power of the power storage device without reducing the difference.

[0062] Here, if the first and second coefficients are equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device to the power grid in the first control is likely to be greater than the effect of the second control in the latter control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device, and the remaining part is covered by the charging power or discharging power of the power storage device, and as a result, the power generated by the photovoltaic power generation device tends to be greater than the charging power or discharging power of the power storage device.

[0063] Therefore, in the power control method of this embodiment, by making the first coefficient γ in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0064] A sixteenth aspect of the power control method of the present disclosure is characterized in that, in the power control method of the first aspect, the distributed power generation device includes a fuel cell device, and when one of the fuel cell device and the power storage device stops abnormally, the first coefficient or the second coefficient used in determining the supply power of the other of the fuel cell device and the power storage device may be changed to a value different from that before the abnormal stop.

[0065] In a case where the distributed power generation device includes a fuel cell device, if one of the fuel cell device and the power storage device abnormally stops, the power supplied by the distributed power generation device may flow back to the power grid. Therefore, in the power control method of this aspect, when one of the fuel cell device and the power storage device abnormally stops, the first coefficient or the second coefficient used to determine the power supplied by the other of the fuel cell device and the power storage device is changed to a desired value different from that before the abnormal stop, thereby making it possible to appropriately suppress the power supplied by the distributed power generation device from flowing back to the power grid, compared to a case where these coefficients are the same before and after the abnormal stop.

[0066] A power control method of a 17th aspect of the present disclosure is the power control method of the first aspect, wherein when the distributed power generation device includes a solar power generation device, and when one of the solar power generation device and the power storage device abnormally stops, the first coefficient or the second coefficient used in determining the power supply of the other of the solar power generation device and the power storage device may be changed to a value different from that before the abnormal stop.

[0067] In a case where the distributed power generation device includes a photovoltaic power generation device, if one of the photovoltaic power generation device and the power storage device abnormally stops, the power supplied by the distributed power generation device may flow back to the power grid. Therefore, in the power control method of this aspect, when one of the photovoltaic power generation device and the power storage device abnormally stops, the first coefficient or the second coefficient used to determine the power supplied by the other of the photovoltaic power generation device and the power storage device is changed to a desired value different from that before the abnormal stop, so that the power supplied by the distributed power generation device can be appropriately suppressed from flowing back to the power grid, compared to a case where these coefficients are the same before and after the abnormal stop.

[0068] An 18th aspect of the power control device of the present disclosure includes a memory device that stores the power demand of a power consumer, and a controller that determines the supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than the demand power of the power consumer when power is supplied to a power load of the power consumer from a distributed power supply system including a distributed power generation device and a power storage device.

[0069] With this configuration, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control device of this aspect are similar to those of the power control method of the first aspect, and therefore will not be described here.

[0070] A distributed power supply system according to a nineteenth aspect of the present disclosure includes a distributed power generation device, a power storage device, and the power control device according to the eighteenth aspect.

[0071] With this configuration, the distributed power system of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the distributed power system of this aspect are similar to those of the power control method of the first aspect, so a detailed description thereof will be omitted.

[0072] Further Aspects of the Disclosure As long as at least one of the first coefficient α, the first coefficient β, the first coefficient γ, and the second coefficient δ is less than 1, the effect of suppressing reverse power flow from the distributed power generation device to the power grid can be achieved even if the other coefficients are 1. From this perspective, the following aspects of the present disclosure can be further devised.

[0073] In a power control method of a 20th aspect of the present disclosure, when power is supplied to a power load of a power consumer from a distributed power system including a solar power generation device, a fuel cell device, and a power storage device, the power generation power of the fuel cell device is determined as a value obtained by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer, the actual power generation power of the solar power generation device, and the planned value of the power generation power of the fuel cell device, and multiplying the result by the first coefficient β and reducing the sum.

[0074] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the third aspect, and therefore will not be described here.

[0075] A power control method of a 21st aspect of the present disclosure, 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, determines the power generation power of the fuel cell device as a value obtained by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation power of the fuel cell device, and reducing the sum by the first coefficient β.

[0076] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the fourth aspect, and therefore will not be described here.

[0077] A 22nd aspect of the power control method of the present disclosure, when supplying power to a power load of a power consumer from a distributed power system including a solar power generation device, a fuel cell device, and a power storage device, determines a power generation upper limit value of the solar power generation device to be a value less than the difference between the sum of the actual power demand of the power consumer and the chargeable power less than the maximum charging power of the power storage device, and the actual power generation power of the fuel cell device, multiplied by the first coefficient γ and reduced.

[0078] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the fifth aspect, and therefore will not be described here.

[0079] A 23rd aspect of the power control method of the present disclosure, when supplying power to a power load of a power consumer from a distributed power system including a solar power generation device and a power storage device, determines a power generation upper limit value of the solar power generation device to be a value obtained by multiplying a value less than the sum of the actual power demand of the power consumer and the chargeable power less than the maximum charging power of the power storage device by the first coefficient γ and reducing it.

[0080] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the sixth aspect, and therefore will not be described here.

[0081] A power control method of a 24th aspect of the present disclosure, when supplying power to a power load of a power consumer from a distributed power system including a solar power generation device, a fuel cell device, and a power storage device, determines the charging power or discharging power of the power storage device as a value obtained by multiplying a difference between the actual demand power of the power consumer and the sum of the actual generated power of the solar power generation device and the actual generated power of the fuel cell device by a second coefficient δ and reducing the result.

[0082] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the seventh aspect, and therefore will not be described here.

[0083] A power control method of a 25th aspect of the present disclosure, when supplying power to a power load of a power consumer from a distributed power system including a solar power generation device, determines a value obtained by multiplying a difference between an actual power demand of the power consumer and an actual power generated by the solar power generation device by a second coefficient δ and reducing the result as the charging power or discharging power of the power storage device.

[0084] According to the above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the eighth aspect, and therefore will not be described here.

[0085] A 26th aspect of the power control method of the present disclosure, when supplying power to a power load of a power consumer from a distributed power system including a fuel cell device and a power storage device, determines the charging power or discharging power of the power storage device as a value obtained by multiplying a difference between the actual power demand of the power consumer and the actual power generated by the fuel cell device by a second coefficient δ and then reducing the result.

[0086] As described above, the power control device of this aspect can reduce the possibility of the power of the distributed power system flowing back to the power grid more than ever before. Note that the details of the effects of the power control method of this aspect are similar to those of the power control method of the ninth aspect, and therefore will not be described here.

[0087] 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.

[0088] 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.

[0089] Furthermore, in the operation of the apparatus, the order of steps may be changed or known steps may be added as necessary.

[0090] (First embodiment) [Device configuration] Fig. 1 is a diagram illustrating an example of a distributed power supply system according to a first embodiment. Fig. 2 is a diagram illustrating an example of a power control device according to the first embodiment.

[0091] 1, a distributed power system 10 of this embodiment includes a power control device 20, a distributed power generation device 31, and a power storage device 32. The specific configuration of the distributed power generation device 31 will be described in an embodiment.

[0092] The power storage device 32 is a device that stores power generated by the distributed power generation device 31 or 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 the power grid under the control of the power control device 20. The power storage device 32 can transmit a charging rate SOC (State of charge) indicating the remaining amount of power (amount of charge) stored in the power storage device 32 to the power control device 20 at an appropriate timing. For example, a well-known secondary battery can be used as the power storage device 32, but is not limited thereto. The power storage device 32 includes a group of storage battery units consisting of a plurality of storage battery units, and the detailed configuration of the power storage device 32 will be described in the second embodiment.

[0093] As shown in FIG. 2, the power control device 20 includes a storage unit 21 and a controller 22.

[0094] The storage device 21 is a memory for storing the power demand of power consumers.

[0095] Here, the "electricity consumer" is an owner of the electric power load 40 that receives the service of the electric power supply generated by the distributed power system 10. Examples of the "electricity consumer" include, but are not limited to, factories, stores, and general households.

[0096] When the distributed power system 10 supplies power to the power load 40 of the power consumer, the controller 22 determines the supply power of the distributed power generation device 31 using a first coefficient so that the supply power of the distributed power generation device 31 is smaller than the demand power of the power consumer. A specific example of the "first coefficient" will be described in the examples.

[0097] 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.

[0098] [Operation] FIG. 3 is a flowchart showing an example of the operation (power control method) of the power control device of the first embodiment.

[0099] The following operations may be performed, for example, by the calculation processing unit of the controller 22 of the power control device 20 reading out a control program from a 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.

[0100] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0101] Next, in step S2, the supply power of the distributed power generation device 31 is determined using a first coefficient so that the supply power is smaller than the demand power of the power consumer.

[0102] According to the present embodiment described above, the possibility of the power of the distributed power system 10 flowing back into the power grid can be reduced more than ever before.

[0103] Specifically, in this embodiment, although there is a high possibility that power purchase from the power grid will occur, this is tolerated and the supply power of the distributed power generation device 31 is determined using a first coefficient so that the supply power of the distributed power generation device 31 is smaller than the demand power of the power consumer. As a result, in this embodiment, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back to the power grid, compared to a case in which the supply power of the distributed power generation device 31 is not determined using the above-mentioned first coefficient.

[0104] (First embodiment) The power control method of the present embodiment is similar to that of the first embodiment, except for the configuration of a distributed power generation device 31 and the control content of a controller 22, which will be described below.

[0105] FIG. 4A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a first example of the first embodiment.

[0106] In the example shown in FIG. 4A, the distributed power generation apparatus 31 includes a solar power generation apparatus 31A and a fuel cell apparatus 31B.

[0107] The solar power generation device 31A generates power by converting light energy into electric power using sunlight under the control of the power control device 20. The electric power generated by the solar power generation device 31A 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 solar power generation device 31A.

[0108] The fuel cell device 31B 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 31B 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 31B. An example of the hydrogen supply source is, but is not limited to, a hydrogen storage tank.

[0109] The distributed power generation device 31 may be, for example, a system that supplies large power to a power grid. In this case, the solar power generation device 31A and the fuel cell device 31B each include a solar cell group consisting of a plurality of solar cells including a solar cell panel, and a fuel cell unit group consisting of a plurality of fuel cell units including a fuel cell stack, and the detailed configuration of such a distributed power generation device 31 will be described in the second embodiment.

[0110] FIG. 4B is a flowchart showing an example of the operation of the power control device (power control method) in the first example of the first embodiment.

[0111] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0112] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0113] Next, in step S2A, a planned value of the generated power of the fuel cell device 31B is determined so as to satisfy the difference between the predicted value or actual power demand of the power consumer multiplied by the first coefficient α and reduced, and the predicted value or actual power generated by the photovoltaic power generator 31A. The actual power demand of the power consumer is, in other words, the actual value of the power demand of the power consumer. The actual power generated by the photovoltaic power generator 31A is, in other words, the actual value of the power generated by the photovoltaic power generator 31A.

[0114] Here, for example, when the power load 40 of the power consumer is a power consuming facility in a factory, the "predicted value of the power demand of the power consumer" can be appropriately determined from factory operation record data indicating past operating days or non-operating days of the factory stored in the memory 21 and record data of power consumption of the power load 40 corresponding to the operating days or non-operating days of the factory. The "actual power demand of the power consumer" is the record value of power consumed by the power load 40, and may be the latest record value data of the power consumption of the power load 40 stored in the memory 21, or may be a moving average value of the most recent record value data of the power consumption of the power load 40 sampled during an appropriate sampling period and stored in the memory 21.

[0115] The "predicted value of the power of the photovoltaic power generation device 31A" can be appropriately determined from past weather data and the like stored in the memory 21. The "actual power generated by the photovoltaic power generation device 31A" may be the latest performance value data of the power generated by the photovoltaic power generation device 31A stored in the memory 21, or may be a moving average value of the most recent performance data of the power generated by the photovoltaic power generation device 31A sampled during an appropriate sampling period and stored in the memory 21.

[0116] Information indicating the "planned value of the power generation power of the fuel cell device 31B" determined in step S2A may be transmitted to a controller of the fuel cell device 31B via a communication network. An example of such a controller may be, but is not limited to, the control device 50B described in the second embodiment.

[0117] The "first coefficient α" is a coefficient for underestimating the predicted value of the power demand of the power consumer or the actual power demand compared to the actual data when determining the planned value of the power generation of the fuel cell device 31B, and may be an appropriate numerical value less than "1" that can be specified by a user, etc. The users include direct and indirect users of the power control device 20. An example of a direct user of the power control device 20 is the administrator of the power control device 20. An example of an indirect user of the power control device 20 is the owner of the distributed power system 10, etc. Such an owner may be the power consumer or a power generation business operator that supplies power to the power consumer using the distributed power system 10.

[0118] The generated power of the fuel cell device 31B (hereinafter referred to as the generated power in the present disclosure) calculated from the difference between the predicted value or actual demand power of the power consumer multiplied by a first coefficient α and reduced, and the predicted value or actual generated power of the power of the solar power generation device 31A is smaller than the generated power of the fuel cell device 31B (hereinafter referred to as the generated power in the comparative example) calculated from the difference between the predicted value or actual demand power of the power consumer and the predicted value or actual generated power of the power of the solar power generation device 31A.

[0119] Here, the "power generated in the comparative example" corresponds to power that is unlikely to induce a reverse power flow from the distributed power generation device 31 to the power grid. In other words, the "power generated in the present disclosure" is power that is further reduced by using the first coefficient α from the power that is unlikely to induce a reverse power flow from the distributed power generation device 31 to the power grid.

[0120] Therefore, in this embodiment, the planned value of the generated power of the fuel cell device 31B is determined so as to satisfy the difference between the value obtained by multiplying the predicted value or actual demand power of the power consumer by the first coefficient α and reducing it, and the predicted value or actual generated power of the solar power generation device 31A. This makes it possible to appropriately suppress the generated power of the fuel cell device 31B from flowing back into the power grid, compared to the case where the planned value of the generated power of the fuel cell device 31B is determined without reducing the predicted value or actual demand power of the power consumer.

[0121] The power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to those of the first embodiment except for the above-mentioned features.

[0122] (Second 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 generation device 31 and the control content of a controller 22, which will be described below.

[0123] FIG. 5A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a second example of the first embodiment.

[0124] In the example shown in FIG. 5A, the distributed power generation system 31 includes a solar power generation system 31A and a fuel cell system 31B. However, the configurations of the solar power generation system 31A and the fuel cell system 31B are similar to those in the first embodiment, and therefore description thereof will be omitted.

[0125] FIG. 5B is a flowchart showing an example of the operation of the power control device (power control method) in the second example of the first embodiment.

[0126] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0127] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0128] Next, in step S2B, the planned value of the power generation of the fuel cell device 31B is added to a correction value of the planned value based on the actual power demand of the power consumer, the actual power generation of the solar power generation device 31A, and the planned value of the power generation of the fuel cell device 31B, and then multiplied by the first coefficient β and reduced, and the resulting value is determined as the power generation of the fuel cell device 31B.

[0129] Here, the "first coefficient β" is a coefficient for underestimating the "planned value of the power generation power of the fuel cell device 31B plus a correction value of the planned value based on the actual power demand of the power consumer, the actual power generation power of the photovoltaic power generation device 31A, and the planned value of the power generation power of the fuel cell device 31B" in determining the power generation power of the fuel cell device 31B, compared to the actual data, and may be an appropriate numerical value less than "1" that can be designated by a user, etc. The "user" is the same as above, and detailed description will be omitted. Information indicating the "power generation power of the fuel cell device 31B" determined in step S2B may be transmitted to the controller of the fuel cell device 31B via a communication network, as above.

[0130] As the "correction value of the planned values ​​based on the actual demand power of the power consumer, the actual generated power of the photovoltaic power generation device 31A, and the planned values ​​of the generated power of the fuel cell device 31B", for example, the difference between the actual demand power of the power consumer and the sum of the planned values ​​of the actual generated power of the photovoltaic power generation device 31A and the generated power of the fuel cell device 31B, or the correction value FC described in the second embodiment, sub These include, but are not limited to:

[0131] Incidentally, the "actual power demand of the power consumer" and the "actual power generation of the solar power generation device 31A" in step S2B are the same as those described above, and therefore detailed explanations thereof will be omitted.

[0132] In the case where the distributed power generation apparatus 31 includes a solar power generation apparatus 31A and a fuel cell apparatus 31B, the sum of the planned value of the power generation power of the fuel cell apparatus 31B and the corrected value of the planned value corresponds to the power generation power of the fuel cell apparatus 31B at which reverse power flow from the distributed power generation apparatus 31 is unlikely to be induced to the power grid from the distributed power generation apparatus 31. In other words, the value obtained by multiplying the combined power of the planned value and the corrected value of the planned value by the first coefficient β and reducing it is the power that is further reduced by using the first coefficient β from the power at which reverse power flow from the distributed power generation apparatus 31 is unlikely to be induced to the power grid.

[0133] Therefore, in this embodiment, by determining the generated power of the fuel cell device 31B as the value obtained by adding the planned value of the generated power of the fuel cell device 31B to a correction value of the planned value and multiplying the result by the first coefficient β and reducing it, it is possible to appropriately prevent the generated power of the fuel cell device 31B from flowing back into the power system, compared to the case where the generated power of the fuel cell device 31B is determined without multiplying it by the first coefficient β.

[0134] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to those of the first embodiment or the first example of the first embodiment.

[0135] (Third 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 generation device 31 and the control content of a controller 22, which will be described below.

[0136] FIG. 6A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a third example of the first embodiment.

[0137] In the example shown in FIG. 6A, the distributed power generation system 31 includes a fuel cell system 31B, but the configuration of the fuel cell system 31B is similar to that of the first embodiment, and therefore a description thereof will be omitted.

[0138] FIG. 6B is a flowchart showing an example of the operation of the power control device (power control method) in the third example of the first embodiment.

[0139] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0141] Next, in step S2C, the power generation power of the fuel cell device 31B is determined to be the value obtained by adding the planned value of the power generation power of the fuel cell device 31B to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation power of the fuel cell device 31B, and then multiplying the result by the first coefficient β and reducing the sum.

[0142] Here, the "first coefficient β" is a coefficient for underestimating the "planned value of the power generation of the fuel cell device 31B plus a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation of the fuel cell device 31B" compared to the actual data when determining the power generation of the fuel cell device 31B, and may be an appropriate numerical value less than "1" that can be designated by a user, etc. The "user" is the same as above, and detailed description will be omitted. Information indicating the "power generation of the fuel cell device 31B" determined in step S2C may be transmitted to the controller of the fuel cell device 31B via a communication network, as above.

[0143] As the "correction value of the planned value based on the actual demand power of the power consumer and the planned value of the generated power of the fuel cell device 31B", for example, the difference between the actual demand power of the power consumer and the planned value of the generated power of the fuel cell device 31B, or the correction value FC sub These include, but are not limited to:

[0144] Incidentally, the "actual power demand of the power consumer" in step S2C is the same as that described above, and therefore a detailed explanation thereof will be omitted.

[0145] In the case where the distributed power generation apparatus 31 includes a fuel cell apparatus 31B, the sum of the planned value of the power generation power of the fuel cell apparatus 31B and the corrected value of the planned value corresponds to the power generation power of the fuel cell apparatus 31B that is unlikely to induce reverse power flow to the power grid from the distributed power generation apparatus 31. In other words, the value obtained by multiplying the combined power of the planned value and the corrected value of the planned value by the first coefficient β and reducing it is the power that is further reduced by using the first coefficient β from the power generation power that is unlikely to induce reverse power flow to the power grid from the distributed power generation apparatus 31.

[0146] Therefore, in this embodiment, by determining the generated power of the fuel cell device 31B as a value obtained by adding a correction value for the planned value of the generated power of the fuel cell device 31B to the planned value and multiplying the result by the first coefficient β and reducing it, it is possible to appropriately prevent the generated power of the fuel cell device 31B from flowing back into the power system, compared to the case where the generated power of the fuel cell device 31B is determined without multiplying by the first coefficient β.

[0147] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any one of the first embodiment and the first to second examples of the first embodiment.

[0148] (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 generation device 31 and the control content of a controller 22, which will be described below.

[0149] FIG. 7A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a fourth example of the first embodiment.

[0150] In the example shown in FIG. 7A, the distributed power generation system 31 includes a solar power generation system 31A and a fuel cell system 31B, but the configurations of the solar power generation system 31A and the fuel cell system 31B are similar to those in the first embodiment, so description thereof will be omitted.

[0151] FIG. 7B is a flowchart showing an example of the operation of the power control device (power control method) in the fourth example of the first embodiment.

[0152] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0153] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0154] Next, in step S2D, a value less than the difference between the sum of the actual demand power of the power consumer and the chargeable power less than the maximum charging power of the storage device 32 and the actual generated power of the fuel cell device 31B is multiplied by the first coefficient γ and reduced, and the power generation upper limit value of the solar power generation device 31A is determined.

[0155] Here, the "first coefficient γ" is a coefficient for underestimating "a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32 and the actual power generation power of the fuel cell device 31B" in determining the power generation upper limit value of the photovoltaic power generation device 31A, compared to the actual data, and may be an appropriate numerical value less than "1" that can be specified by a user or the like. The "user" is the same as above, and detailed description is omitted. Information indicating the "power generation upper limit value of the photovoltaic power generation device 31A" determined in step S2D may be transmitted to a controller of the photovoltaic power generation device 31A via a communication network. An example of such a controller may be, but is not limited to, the control device 50A described in the second embodiment.

[0156] The "maximum charging power of the power storage device 32" is the charging capacity (kW) of the power storage device 32 that is determined according to the specifications and usage conditions of the power storage device 32. The "maximum charging power of the power storage device 32" may be transmitted from the power storage device 32 to the power control device 20 at an appropriate timing.

[0157] The "chargeable power of the power storage device 32" may be, for example, the maximum charging power, or a value less than the maximum charging power that can be designated by a user or the like.

[0158] The "actual power demand of the power consumer" in step S2D is the same as above, and therefore a detailed description thereof will be omitted. The "actual power generated by the fuel cell device 31B" may be the latest performance data of the power generated by the fuel cell device 31B stored in the memory 21, or may be a moving average value of the most recent performance data of the power generated by the fuel cell device 31B sampled during an appropriate sampling period and stored in the memory 21.

[0159] In the case where the distributed power generation apparatus 31 includes a solar power generation apparatus 31A and a fuel cell apparatus 31B, a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage apparatus 32 and the actual power generation by the fuel cell apparatus 31B corresponds to the power generation by the solar power generation apparatus that is unlikely to induce a reverse power flow from the distributed power generation apparatus 31 to the power grid. In other words, the value obtained by multiplying the value equal to or less than the difference by the first coefficient γ is the power further reduced by using the first coefficient β from the power generation by the distributed power generation apparatus 31 that is unlikely to induce a reverse power flow to the power grid.

[0160] For this reason, in this embodiment, by determining the power generation upper limit value of the solar power generation device 31A as a value obtained by multiplying a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the storage device 32, and the actual power generation power of the fuel cell device 31B, by the first coefficient γ and reducing the result, it is possible to appropriately suppress the reverse flow of the power generated by the solar power generation device 31A to the power grid, compared to a case in which the power generation upper limit value of the solar power generation device 31A is determined without reducing the value equal to or less than the difference.

[0161] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to third examples of the first embodiment.

[0162] (Fifth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0163] FIG. 8A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fifth example of the first embodiment.

[0164] In the example shown in FIG. 8A, the distributed power generation apparatus 31 includes a solar power generation apparatus 31A, but the configuration of the solar power generation apparatus 31A is similar to that of the first embodiment, and therefore description thereof will be omitted.

[0165] FIG. 8B is a flowchart showing an example of the operation of the power control device (power control method) in the fifth example of the first embodiment.

[0166] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0167] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0168] Next, in step S2E, a value less than the sum of the actual power demand of the power consumer and the chargeable power less than the maximum charging power of the storage device 32 is multiplied by the first coefficient γ and reduced, and the power generation upper limit value of the solar power generation device 31A is determined.

[0169] Here, the "first coefficient γ" is a coefficient for underestimating "a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32" compared to the actual data in determining the power generation upper limit of the photovoltaic power generation device 31A, and may be an appropriate numerical value less than "1" that can be designated by a user, etc. The "user" is the same as above, and detailed description will be omitted. Information indicating the "power generation upper limit of the photovoltaic power generation device 31A" determined in step S2E may be transmitted to the controller of the photovoltaic power generation device 31A via a communication network, as described above.

[0170] Incidentally, the "actual power demand of the power consumer" and the "maximum charging power of the power storage device 32" in step S2E are the same as those described above, and therefore detailed description thereof will be omitted.

[0171] In the case where the distributed power generation device 31 includes the solar power generation device 31A, a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32 corresponds to the power generated by the solar power generation device 31A that is unlikely to induce reverse power flow to the power grid from the distributed power generation device 31. In other words, the value obtained by multiplying the value equal to or less than the sum by the first coefficient γ is the power further reduced by using the first coefficient γ from the power generated by the distributed power generation device 31 that is unlikely to induce reverse power flow to the power grid.

[0172] For this reason, in this embodiment, by determining the power generation upper limit value of the solar power generation device 31A as a value obtained by multiplying a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the storage device 32 by the first coefficient γ and reducing the result, it is possible to appropriately suppress the reverse flow of power generated by the solar power generation device 31A to the power grid, compared to a case in which the power generation upper limit value of the solar power generation device 31A is determined without reducing the value equal to or less than the sum.

[0173] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to fourth examples of the first embodiment.

[0174] (Sixth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0175] FIG. 9A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a sixth example of the first embodiment.

[0176] In the example shown in FIG. 9A, the distributed power generation system 31 includes a solar power generation system 31A and a fuel cell system 31B, but the configurations of the solar power generation system 31A and the fuel cell system 31B are similar to those in the first embodiment, so description thereof will be omitted.

[0177] FIG. 9B is a flowchart showing an example of the operation of the power control device (power control method) in the sixth example of the first embodiment.

[0178] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0179] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0180] Next, in step S2F, the difference between the actual demand power of the power consumer and the sum of the actual generated power of the solar power generation device 31A and the actual generated power of the fuel cell device 31B is multiplied by a second coefficient δ and then reduced, and the resulting value is determined as the charging power or discharging power of the storage device 32.

[0181] Here, the "second coefficient δ" is a coefficient for underestimating the "difference between the actual power demand of the power consumer and the sum of the actual power generated by the photovoltaic power generation device 31A and the actual power generated by the fuel cell device 31B" in determining the charging power or discharging power of the power storage device 32, compared to the actual data, and may be an appropriate numerical value less than "1" that can be specified by a user, etc. The "user" is the same as above, and detailed description is omitted. Information indicating the "charging power or discharging power of the power storage device 32" determined in step S2F may be transmitted to a controller of the power storage device 32 via a communication network. An example of such a controller may be, but is not limited to, the control device 50C described in the second embodiment.

[0182] Incidentally, the "actual power demand of the power consumer", "actual power generated by the solar power generation device 31A" and "actual power generated by the fuel cell device 31B" in step S2F are the same as those described above, and therefore detailed explanations thereof will be omitted.

[0183] In the case where the distributed power generation apparatus 31 includes a solar power generation apparatus 31A and a fuel cell apparatus 31B, the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation apparatus 31A and the actual power generated by the fuel cell apparatus 31B corresponds to the charging power or discharging power of the power storage apparatus 32 that is unlikely to induce a reverse power flow from the distributed power generation apparatus 31 to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ and reducing it is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation apparatus 31 to the power grid.

[0184] For this reason, in this embodiment, the difference between the actual demand power of the power consumer and the sum of the actual generated power of the solar power generation device 31A and the actual generated power of the fuel cell device 31B is multiplied by the second coefficient δ and reduced to determine the charging power or discharging power of the power storage device 32. This makes it possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to a case in which the charging power or discharging power of the power storage device 32 is determined without reducing the difference.

[0185] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to fifth examples of the first embodiment.

[0186] (Seventh 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 generation device 31 and the control content of a controller 22, which will be described below.

[0187] FIG. 10A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system of a seventh example of the first embodiment.

[0188] In the example shown in FIG. 10A, the distributed power generation apparatus 31 includes a solar power generation apparatus 31A, but the configuration of the solar power generation apparatus 31A is similar to that of the first embodiment, and therefore description thereof will be omitted.

[0189] FIG. 10B is a flowchart showing an example of the operation of the power control device (power control method) in the seventh embodiment of the first embodiment.

[0190] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0191] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0192] Next, in step S2G, the charge power or discharge power of the power storage device 32 is determined to be a value obtained by multiplying the difference between the actual power demand of the power consumer and the actual power generated by the photovoltaic power generation device 31A by the second coefficient δ and then reducing the result.

[0193] Here, the "second coefficient δ" is a coefficient for underestimating the "difference between the actual power demand of the power consumer and the actual power generated by the photovoltaic power generation device 31A" compared to the actual data in determining the charging power or discharging power of the power storage device 32, and may be an appropriate numerical value less than "1" that can be designated by a user, etc. The "user" is the same as above, and detailed description will be omitted. Information indicating the "charging power or discharging power of the power storage device 32" determined in step S2G may be transmitted to the controller of the power storage device 32 via a communication network, as above.

[0194] Incidentally, the "actual power demand of the power consumer" and the "actual power generation of the solar power generation device 31A" in step S2G are the same as those described above, and therefore detailed explanations thereof will be omitted.

[0195] In the case where the distributed power generation device 31 includes a solar power generation device 31A, the difference between the actual power demand of the power consumer and the actual power generation by the solar power generation device 31A corresponds to the charging power or discharging power of the power storage device 32 that is unlikely to induce a reverse power flow from the distributed power generation device 31 to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ and reducing it is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation device 31 to the power grid.

[0196] Therefore, in this embodiment, by determining the charging power or discharging power of the energy storage device 32 as the value obtained by multiplying the difference between the actual power demand of the power consumer and the actual power generated by the solar power generation device 31A by the second coefficient δ and reducing the result, it is possible to appropriately suppress the backflow of the supply power of the distributed power generation device 31 to the power grid, compared to a case in which the charging power or discharging power of the energy storage device 32 is determined without reducing the difference.

[0197] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to sixth examples of the first embodiment.

[0198] (Eighth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0199] FIG. 11A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to an eighth example of the first embodiment.

[0200] In the example shown in FIG. 11A, the distributed power generation system 31 includes a fuel cell system 31B, but the configuration of the fuel cell system 31B is similar to that of the first embodiment, and therefore a description thereof will be omitted.

[0201] FIG. 11B is a flowchart showing an example of the operation of the power control device (power control method) in the eighth embodiment of the first embodiment.

[0202] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0203] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0204] Next, in step S2H, the charge power or discharge power of the power storage device 32 is determined to be a value obtained by multiplying the difference between the actual power demand of the power consumer and the actual power generated by the fuel cell device 31B by the second coefficient δ and then reducing the result.

[0205] Here, the "second coefficient δ" is a coefficient for underestimating the "difference between the actual power demand of the power consumer and the actual power generated by the fuel cell device 31B" compared to the actual data when determining the charging power or discharging power of the power storage device 32, and may be an appropriate numerical value less than "1" that can be designated by a user, etc. The "user" is the same as above, and detailed description will be omitted. Information indicating the "charging power or discharging power of the power storage device 32" determined in step S2H ​​may be transmitted to the controller of the power storage device 32 via a communication network, as above.

[0206] Incidentally, the "actual power demand of the power consumer" and the "actual power generation of the fuel cell device 31B" in step S2H ​​are the same as those described above, and therefore detailed explanations thereof will be omitted.

[0207] In the case where the distributed power generation apparatus 31 includes the fuel cell apparatus 31B, the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell apparatus 31B corresponds to the charging power or discharging power of the power storage apparatus 32 that is unlikely to induce a reverse power flow from the distributed power generation apparatus 31 to the power grid. In other words, the value obtained by multiplying the difference by the second coefficient δ is the power that is further reduced by using the second coefficient δ from the power that is unlikely to induce a reverse power flow from the distributed power generation apparatus 31 to the power grid.

[0208] Therefore, in this embodiment, by determining the charge power or discharge power of the energy storage device 32 as the value obtained by multiplying the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell device 31B by the second coefficient δ and reducing the result, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to a case in which the charge power or discharge power of the energy storage device 32 is determined without reducing the difference.

[0209] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to seventh examples of the first embodiment.

[0210] (Ninth Example) The power control method of this embodiment is similar to that of the first embodiment, except that the first coefficient varies depending on the season. The "first coefficient" can be easily understood from the above description, so a detailed description will be omitted.

[0211] As an example, the "first coefficient α", "first coefficient β" and "first coefficient γ" may be set to be different depending on the season, as shown in the following Table 1. However, these numerical values ​​are merely examples and are not limited to this example.

[0212] [Table 1]

[0213] In general, the power generated by the photovoltaic power generation device 31A and the power demand of the power consumer change depending on the season. Therefore, in this embodiment, by setting the first coefficient to a desired value depending on the season, the amount of power flowing back from the distributed power generation device 31 to the power grid can be reduced compared to the case where the first coefficient is constant for each season.

[0214] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to eighth examples of the first embodiment.

[0215] (Tenth Example) The power control method of this embodiment is similar to any of the sixth to eighth embodiments of the first embodiment, except that the second coefficient varies depending on the season. The "second coefficient" can be easily understood from the above description, so a detailed explanation will be omitted.

[0216] As an example, the "second coefficient δ" may be set to be different depending on the season, as shown in the above Table 1. However, these numerical values ​​are merely examples and are not limited to this example.

[0217] In general, the power generated by the photovoltaic power generation device 31A and the power demand of the power consumer change depending on the season. Therefore, in this embodiment, by setting the second coefficient to a desired value depending on the season, the amount of power flowing back from the distributed power generation device 31 to the power grid can be reduced compared to the case where the second coefficient is constant for each season.

[0218] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to ninth examples of the first embodiment.

[0219] (Eleventh 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 generation device 31 and the control content of a controller 22, which will be described below.

[0220] FIG. 12A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to an eleventh example of the first embodiment.

[0221] In the example shown in FIG. 12A, the distributed power generation system 31 includes a solar power generation system 31A and a fuel cell system 31B, but the configurations of the solar power generation system 31A and the fuel cell system 31B are similar to those in the first embodiment, so description thereof will be omitted.

[0222] FIG. 12B is a flowchart showing an example of the operation of the power control device (power control method) in the eleventh embodiment of the first embodiment.

[0223] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0224] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0225] Next, in step S2I, a first control is executed to determine the generated power of the fuel cell device 31B as a value obtained by adding the planned value of the generated power of the fuel cell device 31B to the actual power demand of the power consumer, the actual generated power of the photovoltaic power generation device 31A, and a correction value of the planned value based on the planned value of the generated power of the fuel cell device 31B, and multiplying the result by a first coefficient β to reduce the result, or a second control is executed to determine the charging power or discharging power of the power storage device 32 as a value obtained by multiplying the difference between the actual power demand of the power consumer and the sum of the actual generated power of the photovoltaic power generation device 31A and the actual generated power of the fuel cell device 31B by a second coefficient δ to reduce the result. Here, the first coefficient β is smaller than the second coefficient δ.

[0226] The "first control" in step S2I can be easily understood from the description of the second embodiment, and therefore a detailed description thereof will be omitted. The "second control" in step S2I can be easily understood from the description of the sixth embodiment, and therefore a detailed description thereof will be omitted.

[0227] As described above, in this embodiment, a first control is executed to determine the generated power of the fuel cell device 31B as a value obtained by adding a correction value for the planned value of the generated power of the fuel cell device 31B to the planned value, and then multiplying the result by the first coefficient β and reducing the value. This makes it possible to appropriately suppress the generated power of the fuel cell device 31B from flowing back into the power grid, compared to the case in which control is executed to determine the generated power of the fuel cell device 31B without multiplying by the first coefficient β.

[0228] Furthermore, in this embodiment, as described above, a second control is executed in which the charge power or discharge power of the power storage device 32 is determined by multiplying the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation device 31A and the actual power generated by the fuel cell device 31B by the second coefficient δ and reducing the result, thereby making it possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to a case in which control is executed in which the charge power or discharge power of the power storage device 32 is determined without reducing the difference.

[0229] If the first and second coefficients are of equal magnitude, the effect of suppressing reverse power flow from the distributed power generation apparatus 31 to the power grid in the first control is likely to be greater than the effect of the second control in the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation apparatus 31, and the remaining portion is covered by the charging power or discharging power of the power storage apparatus 32. As a result, the power generated by the fuel cell apparatus 31B tends to be greater than the charging power or discharging power of the power storage apparatus 32.

[0230] Therefore, as in this embodiment, by making the first coefficient β in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0231] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to tenth examples of the first embodiment.

[0232] (Twelfth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0233] FIG. 13A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a twelfth example of the first embodiment.

[0234] In the example shown in FIG. 13A, the distributed power generation system 31 includes a fuel cell system 31B, but the configuration of the fuel cell system 31B is similar to that of the first embodiment, and therefore a description thereof will be omitted.

[0235] FIG. 13B is a flowchart showing an example of the operation of the power control device (power control method) in the twelfth embodiment of the first embodiment.

[0236] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0237] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0238] Next, in step S2J, a first control is executed to determine the generated power of the fuel cell device 31B as a value obtained by adding the planned value of the generated power of the fuel cell device 31B to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the generated power of the fuel cell device 31B, multiplying the result by a first coefficient β and reducing the sum, or a second control is executed to determine the charging power or discharging power of the power storage device 32 as a value obtained by multiplying the difference between the actual power demand of the power consumer and the actual generated power of the fuel cell device 31B by a second coefficient δ and reducing the sum. Here, the first coefficient β is smaller than the second coefficient δ.

[0239] The "first control" in step S2J can be easily understood from the description of the third embodiment, and therefore a detailed description thereof will be omitted. The "second control" in step S2J can be easily understood from the description of the eighth embodiment, and therefore a detailed description thereof will be omitted.

[0240] As described above, in this embodiment, a first control is executed to determine the generated power of the fuel cell device 31B as a value obtained by adding a correction value for the planned value of the generated power of the fuel cell device 31B to the planned value, multiplying the result by the first coefficient β, and reducing the result. This makes it possible to appropriately suppress the generated power of the fuel cell device 31B from flowing back into the power grid, compared to the case in which control is executed to determine the generated power of the fuel cell device 31B without multiplying it by the first coefficient β.

[0241] Furthermore, in this embodiment, as described above, a second control is executed in which the charge power or discharge power of the power storage device 32 is determined by multiplying the difference between the actual power demand of the power consumer and the actual power generation of the fuel cell device 31B by the second coefficient δ and reducing the result, thereby making it possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to a case in which control is executed in which the charge power or discharge power of the power storage device is determined without reducing the difference.

[0242] If the first and second coefficients are of equal magnitude, the effect of suppressing reverse power flow from the distributed power generation apparatus 31 to the power grid in the first control is likely to be greater than the effect of the second control in the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation apparatus 31, and the remaining portion is covered by the charging power or discharging power of the power storage apparatus 32. As a result, the power generated by the fuel cell apparatus 31B tends to be greater than the charging power or discharging power of the power storage apparatus 32.

[0243] Therefore, as in this embodiment, by making the first coefficient β in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0244] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to eleventh examples of the first embodiment.

[0245] (Thirteenth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0246] FIG. 14A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a thirteenth example of the first embodiment.

[0247] In the example shown in FIG. 14A, the distributed power generation system 31 includes a solar power generation system 31A and a fuel cell system 31B, but the configurations of the solar power generation system 31A and the fuel cell system 31B are similar to those in the first embodiment, so description thereof will be omitted.

[0248] FIG. 14B is a flowchart showing an example of the operation of the power control device (power control method) in the thirteenth embodiment of the first embodiment.

[0249] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0250] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0251] Next, in step S2K, a first control is executed to determine a power generation upper limit value of the photovoltaic power generation device 31A by multiplying a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32 and the actual generated power of the fuel cell device 31B by a first coefficient γ, and then reducing the result, or a second control is executed to determine a charge power or discharge power of the power storage device 32 by multiplying a value equal to or less than the difference between the actual power demand of the power consumer and the sum of the actual generated power of the photovoltaic power generation device 31A and the actual generated power of the fuel cell device 31B by a second coefficient δ, and then reducing the result. Here, the first coefficient γ is smaller than the second coefficient δ.

[0252] The "first control" in step S2K can be easily understood from the description of the fourth embodiment, and therefore a detailed description thereof will be omitted. The "second control" in step S2K can be easily understood from the description of the sixth embodiment, and therefore a detailed description thereof will be omitted.

[0253] As described above, in this embodiment, a first control is executed to determine the power generation upper limit value of the solar power generation device 31A as a value obtained by multiplying a value equal to or less than the difference between the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32, and the actual power generation power of the fuel cell device 31B, by the first coefficient γ, and reducing the result. This makes it possible to appropriately suppress the reverse flow of power generated by the solar power generation device 31A to the power grid, compared to a case in which control is executed to determine the power generation upper limit value of the solar power generation device 31A without reducing a value equal to or less than the difference.

[0254] Furthermore, in this embodiment, as described above, a second control is executed in which the charge power or discharge power of the power storage device 32 is determined by multiplying the difference between the actual power demand of the power consumer and the sum of the actual power generated by the solar power generation device 31A and the actual power generated by the fuel cell device 31B by the second coefficient δ and reducing the result, thereby making it possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to a case in which control is executed in which the charge power or discharge power of the power storage device 32 is determined without reducing the difference.

[0255] Here, if the first coefficient and the second coefficient are assumed to be equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device 31 to the power grid in the first control is likely to be greater than the effect of the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device 31, and the remaining part is covered by the charging power or discharging power of the power storage device 32. As a result, the power generated by the photovoltaic power generation device 31A tends to be greater than the charging power or discharging power of the power storage device 32.

[0256] Therefore, as in this embodiment, by making the first coefficient γ in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0257] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to twelfth examples of the first embodiment.

[0258] (14th 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 generation device 31 and the control content of a controller 22, which will be described below.

[0259] FIG. 15A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fourteenth example of the first embodiment.

[0260] In the example shown in FIG. 15A, the distributed power generation apparatus 31 includes a solar power generation apparatus 31A, but the configuration of the solar power generation apparatus 31A is similar to that of the first embodiment, and therefore a description thereof will be omitted.

[0261] FIG. 15B is a flowchart showing an example of the operation of the power control device (power control method) in the fourteenth embodiment of the first embodiment.

[0262] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0263] First, in step S1, power is supplied from the distributed power system 10 to the power load 40 of the power consumer.

[0264] Next, in step S2L, a first control is executed to determine a power generation upper limit value of the photovoltaic power generation device 31A by multiplying a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device 32 by a first coefficient γ and reducing the result, or a second control is executed to determine a value equal to or less than the difference between the actual power demand of the power consumer and the actual power generated by the photovoltaic power generation device 31A by multiplying the difference by a second coefficient δ and reducing the result, as the charging power or discharging power of the power storage device 32. Here, the first coefficient γ is smaller than the second coefficient δ.

[0265] The "first control" in step S2L can be easily understood from the description of the fifth embodiment, and therefore a detailed description thereof will be omitted. The "second control" in step S2L can be easily understood from the description of the seventh embodiment, and therefore a detailed description thereof will be omitted.

[0266] As described above, in this embodiment, the first control is executed to determine the power generation upper limit value of the solar power generation device 31A as a value obtained by multiplying a value equal to or less than the sum of the actual power demand of the power consumer and the chargeable power equal to or less than the maximum charging power of the storage device 32 by the first coefficient γ and reducing the result, thereby making it possible to appropriately suppress the reverse flow of power generated by the solar power generation device 31A to the power grid compared to the case in which control is executed to determine the power generation upper limit value of the solar power generation device 31A as a value equal to or less than the sum without reducing it.

[0267] Furthermore, in this embodiment, as described above, the second control is executed to determine the charging power or discharging power of the power storage device 32 as a value obtained by multiplying the difference between the actual power demand of the power consumer and the actual power generated by the solar power generation device 31A by the second coefficient δ and reducing the result, thereby making it possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to the case in which control is executed to determine the charging power or discharging power of the power storage device 32 without reducing the difference.

[0268] Here, if the first coefficient and the second coefficient are assumed to be equal in magnitude, the effect of suppressing reverse power flow from the distributed power generation device 31 to the power grid in the first control is likely to be greater than the effect of the second control. This is because, generally, most of the power demand of a power consumer is covered by the power supplied from the distributed power generation device 31, and the remaining part is covered by the charging power or discharging power of the power storage device 32. As a result, the power generated by the photovoltaic power generation device 31A tends to be greater than the charging power or discharging power of the power storage device 32.

[0269] Therefore, as in this embodiment, by making the first coefficient γ in the first control smaller than the second coefficient δ in the second control, it is possible to appropriately suppress the supply power of the distributed power generation device 31 from flowing back into the power grid, compared to when the magnitudes of the two are equal or the magnitude relationship between the two is reversed.

[0270] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to thirteenth examples of the first embodiment.

[0271] (Fifteenth 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 generation device 31 and the control content of a controller 22, which will be described below.

[0272] FIG. 16A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a fifteenth example of the first embodiment.

[0273] In the example shown in FIG. 16A, the distributed power generation system 31 includes a fuel cell system 31B, but the configuration of the fuel cell system 31B is similar to that of the first embodiment, so a description thereof will be omitted.

[0274] FIG. 16B is a flowchart showing an example of the operation of the power control device (power control method) in the fifteenth embodiment of the first embodiment.

[0275] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0276] When power is supplied from the distributed power system 10 to the power load 40 of the power consumer, if one of the fuel cell device 31B and the power storage device 32 stops abnormally (if "Yes" in step S3A), the first coefficient or the second coefficient used to determine the supply power of the other of the fuel cell device 31B and the power storage device 32 is changed to a value different from that before the abnormal stop in step S4A. Specifically, when the power storage device 32 stops abnormally, the first coefficient α, the first coefficient β, or the first coefficient γ may be changed so that these coefficients are smaller than those before the abnormal stop. When the fuel cell device 31B stops abnormally, the first coefficient γ or the second coefficient δ may be changed so that these coefficients are smaller than those before the abnormal stop. Note that the "first coefficient" and the "second coefficient" are the same as those described above, and detailed explanations will be omitted.

[0277] In a case where the distributed power generation apparatus 31 includes a fuel cell apparatus 31B, if one of the fuel cell apparatus 31B and the power storage apparatus 32 stops abnormally, the power supplied by the distributed power generation apparatus 31 may flow back to the power grid. For this reason, in this embodiment, when one of the fuel cell apparatus 31B and the power storage apparatus 32 stops abnormally, the first coefficient or the second coefficient used in determining the power supplied by the other of the fuel cell apparatus 31B and the power storage apparatus 32 is changed to a desired value different from that before the abnormal stop, thereby making it possible to appropriately suppress the power supplied by the distributed power generation apparatus 31 from flowing back to the power grid, compared to a case where these coefficients are the same before and after the abnormal stop.

[0278] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to fourteenth examples of the first embodiment.

[0279] (16th 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 generation device 31 and the control content of a controller 22, which will be described below.

[0280] FIG. 17A is a diagram showing an example of a distributed power generation device provided in a distributed power generation system according to a sixteenth example of the first embodiment.

[0281] In the example shown in FIG. 17A, the distributed power generation apparatus 31 includes a solar power generation apparatus 31A, but the configuration of the solar power generation apparatus 31A is similar to that of the first embodiment, and therefore description thereof will be omitted.

[0282] FIG. 17B is a flowchart showing an example of the operation of the power control device (power control method) in the 16th embodiment of the first aspect.

[0283] The following operations may be performed, for example, by an arithmetic processing unit of the controller 22 (see FIG. 2) of the power control device 20 reading out a control program from a 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.

[0284] When power is supplied from the distributed power supply system 10 to the power load 40 of the power consumer, if one of the photovoltaic power generation device 31A and the power storage device 32 stops abnormally (if "Yes" in step S3B), in step S4B, the first coefficient or the second coefficient used to determine the supply power of the other of the photovoltaic power generation device 31A and the power storage device 32 is changed to a value different from that before the abnormal stop. Specifically, when the power storage device 32 stops abnormally, the first coefficient α, the first coefficient β, or the first coefficient γ may be changed so that these coefficients are smaller than those before the abnormal stop. When the photovoltaic power generation device 31A stops abnormally, the first coefficient α, the first coefficient β, or the second coefficient δ may be changed so that these coefficients are smaller than those before the abnormal stop. The "first coefficient" and the "second coefficient" are the same as those described above, and detailed explanations will be omitted.

[0285] In a case where the distributed power generation apparatus 31 includes a photovoltaic power generation apparatus 31A, if one of the photovoltaic power generation apparatus 31A and the power storage apparatus 32 stops abnormally, the power supplied by the distributed power generation apparatus 31 may flow back to the power grid. For this reason, in this embodiment, when one of the photovoltaic power generation apparatus 31A and the power storage apparatus 32 stops abnormally, the first coefficient or the second coefficient used to determine the power supplied by the other of the photovoltaic power generation apparatus 31A and the power storage apparatus 32 is changed to a desired value different from that before the abnormal stop, thereby making it possible to appropriately suppress the power supplied by the distributed power generation apparatus 31 from flowing back to the power grid, compared to a case where these coefficients are the same before and after the abnormal stop.

[0286] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to fifteenth examples of the first embodiment.

[0287] Second embodiment [Device configuration] Fig. 18 is a diagram showing an example of a distributed power system according to the second embodiment. In Fig. 18, 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.

[0288] As shown in Fig. 18, the distributed power system 10 of this embodiment includes a power control device 20, a solar power generation device 31A, a fuel cell device 31B, a power storage device 32, and control devices 50A to 50C. That is, in the example shown in Fig. 18, the distributed power generation device 31 includes a solar power generation device 31A and a fuel cell device 31B.

[0289] 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.

[0290] In the example shown in Fig. 18, the photovoltaic power generation device 31A 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 composed 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 distributed power system 10, etc.

[0291] The fuel cell device 31B 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, and the 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 distributed power system 10, etc.

[0292] Although not shown, each of these fuel cell units is composed of a fuel cell stack that generates electricity using hydrogen, auxiliary equipment such as pumps and valves, 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-mentioned devices may be directly controlled by the control device 50A.

[0293] 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, and the plurality of storage battery 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 via 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 distributed power system 10, etc.

[0294] Furthermore, the solar power generation device 31A, the fuel cell device 31B and the power storage device 32 are connected to each other in parallel 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.

[0295] However, the above configuration of the distributed 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 power storage 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.

[0296] The control devices 50A to 50C are provided corresponding to the solar power generation device 31A, the fuel cell device 31B and the power storage device 32, respectively, and are connected to the power control device 20 via a communications network.

[0297] The control device 50A may control the output of the solar power generation device 31A by controlling a power conditioner (PCS) via a communication network, or may use the power conditioner (PCS) to disconnect or connect a desired number of solar cells to the power grid.

[0298] The controller 50B may also control the output of each of these fuel cell units via the communications network to enable efficient operation (eg, optimisation of life span) of the fuel cell units.

[0299] The control device 50C may also control the charging power or discharging power of the power storage device 32 by controlling a power conditioner (PCS) via a communication network.

[0300] However, the above is merely an example and is not limited to this example. For example, the controller 22 (see FIG. 2) 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.

[0301] 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.

[0302] [Operation] 19A and 19B are flow charts showing an example of the operation for determining the power generation power of the fuel cell device by the power control device of the second embodiment.

[0303] 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.

[0304] The operation of the power control device 20 in FIG. 19A will now be described.

[0305] First, in step S11, the planned value FC of the generated power FC of the fuel cell device 31B is calculated from the power database. mainThe charging rate SOC of the power storage device 32, the power demand D, and the solar cell generated power PV during the sampling period (TD) 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.

[0306] Then, in step S12, the moving average value D of the power demand D during the sampling period is calculated. ave and the moving average value of solar cell power generation PV ave is calculated.

[0307] 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)

[0308] 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.

[0309] 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) may be about 60 minutes, but is not limited to this. SOC lator =SOC-(B pre1 ×T) / Capacity of storage device (2)

[0310] Next, in step S15A, the charging rate SOC lator is the upper limit SOC upper It is determined whether it is greater than

[0311] Charging rate SOC lator is the upper limit SOC upper(if "Yes" in step S15A), in step S16A, the charging power or discharging power B pre2 is calculated. SOC upper =SOC-(B pre2 ×T) / power storage device capacity...(3A)

[0312] In addition, B pre2 When it is >0, it means the discharge power of the storage device 32, and B pre2 When it is <0, it means the charging power of the power storage device 32.

[0313] Next, in step S17A, a correction value FC of the generated power FC of the fuel cell device 31B 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)

[0314] Then, in step S18A, the generated power FC of the fuel cell device 31B is calculated by the following equation (5A), and this generated power FC is issued as a command. FC=FC main +FC sub (5A)

[0315] 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 31B 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.

[0316] The operation of the power control device 20 in FIG. 19B will now be described.

[0317] It should be noted that steps S11 to S14 in FIG. 19B are similar to steps S11 to S14 in FIG. 19A, and therefore the description thereof will be omitted.

[0318] In step S15B, the charging rate SOC lator is the lower limit SOC lower It is determined whether it is smaller than

[0319] Charging rate SOC lator is the lower limit SOC lower (if "Yes" in step S15B), in step S16B, the charging power or discharging power B pre2 is calculated. SOC lower =SOC-(B pre2 ×T) / power storage device capacity...(3B)

[0320] Next, in step S17B, a corrected value FC of the generated power FC of the fuel cell device 31B 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)

[0321] Then, in step S18B, the generated power FC of the fuel cell device 31B is calculated by the following equation (5B), and this generated power FC is issued as a command. FC=FC main +FC sub (5B)

[0322] 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 31B is maintained as it is.sub But the charging rate SOC lator and upper limit SOC lower However, 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.

[0323] According to the present embodiment described above, an example of the “correction value” in the second example of the first embodiment (correction value FC sub ) is derived as above. In each of the above formulas, PV ave , zero (PV ave =0), an example of the "correction value" in the third embodiment of the first embodiment (correction value FC sub ) is derived.

[0324] Other than the above-mentioned features, the power control method, power control device 20, and distributed power system 10 of this embodiment may be similar to any of the first embodiment and the first to sixteenth examples of the first embodiment.

[0325] The first embodiment, the first to sixteenth 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]

[0326] An aspect of the present disclosure can be used in a power control method, a power control device, and a distributed power system that can reduce the possibility of power from a distributed power system flowing back into a power grid more than ever before. [Explanation of symbols]

[0327] 10: Distributed power systems 20: Power control device 21: Memory device 22: Controller 31: Distributed power generation equipment 31A: Solar power generation equipment 31B: Fuel cell device 32: Electricity storage device 40: Power load 50A: Control device 50B: Control device 50C: Control device α : First coefficient β : First coefficient γ : First coefficient δ : second coefficient

Claims

1. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; A power control method for determining a planned value of the power generation power of the fuel cell device so as to satisfy the difference between a value obtained by multiplying the actual power demand of the power consumer by the first coefficient α and reducing it, and a predicted value or actual power generation power of the solar power generation device.

2. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; A power control method in which the power generation power of the fuel cell device is determined as a value obtained by multiplying the first coefficient β by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer, the actual power generation power of the solar power generation device, and the planned value of the power generation power of the fuel cell device, and then reducing the sum.

3. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a fuel cell system; A power control method in which the power generation power of the fuel cell device is determined as a value obtained by multiplying the first coefficient β by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation power of the fuel cell device, and then reducing the sum.

4. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; a power control method for determining, as a power generation upper limit value of the solar power generation device, a value less than the difference between the sum of the actual power demand of the power consumer and the chargeable power less than the maximum charging power of the storage device, and the actual power generation power of the fuel cell device, multiplied by the first coefficient γ and reduced thereby.

5. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation device includes a solar power generation device; a power control method for determining a power generation upper limit value of the solar power generation device as a value obtained by multiplying a value equal to or less than the sum of an actual power demand of the power consumer and a chargeable power equal to or less than a maximum charging power of the storage device by the first coefficient γ and reducing the result.

6. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; a difference between the actual power demand of the power consumer and the sum of the actual power generated by a solar power generation device and an actual power generated by a fuel cell device, multiplied by a second coefficient δ and then reduced to obtain a value that is determined as the charging power or discharging power of the power storage device.

7. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation device includes a solar power generation device; a difference between an actual power demand of the power consumer and an actual power generated by a photovoltaic power generation device is multiplied by a second coefficient δ and reduced to determine the charging power or discharging power of the power storage device.

8. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a fuel cell system; a difference between an actual power demand of the power consumer and an actual power generated by a fuel cell device is multiplied by a second coefficient δ and reduced to determine the charging power or discharging power of the power storage device.

9. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: A power control method, wherein the first coefficient varies depending on a season.

10. The power control method according to any one of claims 6 to 8, wherein the second coefficient varies depending on the season.

11. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; a first control in which the power generation power of the fuel cell device is determined to be a value obtained by multiplying the first coefficient β by adding a correction value of the planned value based on the actual power demand of the power consumer, the actual power generation power of the solar power generation device, and the planned value of the power generation power of the fuel cell device to the planned value of the power generation power of the fuel cell device, and then reducing the sum of the sum by the first coefficient β; or execute a second control in which a difference between an actual demand power of the power consumer and a sum of an actual generated power of the photovoltaic power generation device and an actual generated power of the fuel cell device is multiplied by the second coefficient δ, and the resulting reduced value is determined as the charging power or discharging power of the power storage device; The power control method according to claim 1, wherein the first coefficient β is smaller than the second coefficient δ.

12. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a fuel cell system; a first control in which a value obtained by adding a planned value of the power generation power of the fuel cell device to a correction value of the planned value based on the actual power demand of the power consumer and the planned value of the power generation power of the fuel cell device, and multiplying the result by the first coefficient β, and reducing the result, is determined as the power generation power of the fuel cell device; or execute a second control in which a value obtained by multiplying a difference between an actual power demand of the power consumer and an actual power generated by the fuel cell device by the second coefficient δ and reducing the result is determined as the charging power or discharging power of the power storage device; The power control method according to claim 1, wherein the first coefficient β is smaller than the second coefficient δ.

13. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a solar power generation system and a fuel cell system; a first control in which a value equal to or less than a difference between the sum of the actual demand power of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device and the actual power generation power of the fuel cell device is multiplied by the first coefficient γ and reduced, as the power generation upper limit value of the solar power generation device; or execute a second control in which a difference between an actual demand power of the power consumer and a sum of an actual generated power of the photovoltaic power generation device and an actual generated power of the fuel cell device is multiplied by the second coefficient δ, and the resulting reduced value is determined as the charging power or discharging power of the power storage device; The power control method, wherein the first coefficient γ is smaller than the second coefficient δ.

14. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation device includes a solar power generation device; A first control in which a value equal to or less than the sum of the actual demand power of the power consumer and the chargeable power equal to or less than the maximum charging power of the power storage device is multiplied by the first coefficient γ and reduced to the resultant value is determined as the power generation upper limit value of the photovoltaic power generation device; or execute a second control in which a value obtained by multiplying a difference between an actual power demand of the power consumer and an actual power generated by the photovoltaic power generation device by the second coefficient δ and reducing the result is determined as the charging power or discharging power of the power storage device; The power control method, wherein the first coefficient γ is smaller than the second coefficient δ.

15. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation system includes a fuel cell system; A power control method in which, when one of the fuel cell device and the power storage device stops abnormally, the first coefficient or the second coefficient used in determining the supply power of the other of the fuel cell device and the power storage device is changed to a value different from that before the abnormal stop.

16. A power control method, when supplying power to a power load of a power consumer from a distributed power supply system including a distributed power generation device and a power storage device, determining a supply power of the distributed power generation device using a first coefficient so that the supply power of the distributed power generation device is smaller than a demand power of the power consumer, comprising: the distributed power generation device includes a solar power generation device; A power control method, when one of the solar power generation device and the power storage device abnormally stops, changing the first coefficient or the second coefficient used in determining the supply power of the other of the solar power generation device and the power storage device to a value different from that before the abnormal stop.

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