JP2017070005A - Power supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply system capable of suppressing an increase of power purchase amount from a commercial power supply.SOLUTION: The power supply system includes: a fuel cell capable of supplying generated electric power to a load; a power storage device capable of discharging charged electric power to a load when power consumption of the load exceeds a predetermined threshold value; a control unit of the power storage device which stores a history of the power generation amount of the fuel cell and changes the predetermined threshold value on the basis of the stored history.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a technology of a power supply system.

  Conventionally, a technology of a power supply system including a fuel cell capable of supplying generated power to a load and a power storage device capable of discharging charged power to the load is known. For example, as described in Patent Document 1.

  The power supply system described in Patent Literature 1 includes a fuel cell capable of supplying generated power to a load, and a power storage device capable of discharging charged power to the load. In the power supply system, the power generated by the fuel cell is supplied to the load, and when the power generated by the fuel cell is insufficient with respect to the power consumption of the load, the insufficient power is discharged from the power storage device. To do. With such a configuration, the power supply system can be operated efficiently.

  In the power supply system, the fuel cell may have a learning function for learning information related to power consumption of a load. In such a case, the fuel cell creates a power generation plan based on the information learned by the learning function and generates power according to the created power generation plan. With such a configuration, the power supply system can generate power from the fuel cell at an optimal timing.

  In such a case, the power storage device is discharged when the power consumption of the load exceeds the maximum generated power of the fuel cell. With such a configuration, it is possible to prevent the learning function of the fuel cell from being hindered by the power discharged from the power storage device.

JP20141659593A

  However, in the case described above, for example, when the power generated by the fuel cell is smaller than the maximum generated power, if the power shortage with respect to the power consumption of the load is purchased from the commercial power source, the load It is determined that the power consumption of the battery does not exceed the maximum generated power of the fuel cell, and the power storage device may not be discharged. That is, in such a case, there is room for improvement because the power storage device is not discharged and the amount of power purchased from the commercial power source increases.

  The present invention has been made in view of the above situation, and a problem to be solved is to provide a power supply system capable of suppressing an increase in the amount of power purchased from a commercial power source.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, the power supply system includes a fuel cell capable of supplying generated power to a load, a power storage device capable of discharging charged power to the load when the power consumption of the load exceeds a predetermined threshold, and the fuel Control means for storing a history of the amount of power generated by the battery and changing the predetermined threshold based on the stored history.

In the power supply system, the control unit may calculate an average value of the power generation amount of the fuel cell from the stored history, and change the predetermined threshold based on the calculated average value. .
With such a configuration, it is possible to suppress an increase in the amount of power purchased from a commercial power source.

The power supply system may be configured such that the power storage device is based on a value obtained by subtracting the power generated by the fuel cell from the power consumption of the load when the power consumption of the load exceeds the predetermined threshold. May be discharged.
With such a configuration, it is possible to prevent the power generation of the fuel device from being hindered.

  An increase in the amount of power purchased from a commercial power source can be suppressed.

The block diagram which showed the structure of the electric power supply system which concerns on this embodiment. The flowchart which showed the change of the threshold value in an electrical storage apparatus. (A) The schematic diagram which showed the specific supply aspect regarding the discharge of an electrical storage apparatus in case 700 W is set as a threshold value among the supply aspects of the electric power supply system which concerns on this embodiment. (B) Similarly, a schematic diagram. (A) The schematic diagram which showed the specific supply aspect regarding the discharge of an electrical storage apparatus in case 400 W is set as a threshold value among the supply aspects of the electric power supply system which concerns on this embodiment. (B) Similarly, a schematic diagram. The block diagram which showed another example of the structure of the electric power supply system which concerns on this embodiment. The schematic diagram which showed the specific supply aspect regarding discharge of an electrical storage apparatus among the supply aspects of the electric power of the conventional power supply system.

  Below, the structure of the electric power supply system 1 which concerns on this embodiment is demonstrated using FIG.

  The power supply system 1 is provided in various facilities (in the present embodiment, a house), and supplies power to a load (not shown). The power supply system 1 mainly includes a distribution board 2, a first power path 21, a solar power generation unit 3, a power conditioner 4, a first power sensor 11, a fuel cell 5, and a second power sensor. 12, a third power sensor 13, a power storage device 6, and a second power path 22.

  The distribution board 2 distributes the supplied power to the load. The distribution board 2 is connected to the commercial power source 100, the solar power generation unit 3, the fuel cell 5, and the power storage device 6 as a power supply source through a predetermined power path.

  In addition, in this embodiment, a load is a circuit to which electrical appliances that consume power in a house are connected. For example, the load is provided for each room or for each outlet dedicated to a device that consumes a large amount of power, and is connected to the distribution board 2.

  The first power path 21 is a path through which power can be distributed. The first power path 21 is composed of a conducting wire or the like. One end of the first power path 21 is connected to a commercial power source 100 (a power system of a power company). The other end of the first power path 21 is connected to the distribution board 2. In this way, the distribution board 2 and the commercial power source 100 are configured to allow power to flow through the first power path 21.

  The solar power generation unit 3 generates power using natural energy (sunlight). The solar power generation unit 3 is configured by a solar cell panel or the like (not shown). The solar power generation unit 3 is installed in a sunny place such as on the roof of a house. The solar power generation unit 3 is configured to generate electric power (DC power) and to output the generated electric power. The photovoltaic power generation unit 3 is connected to a midway part of the first power path 21 (hereinafter referred to as “first connection part 31”).

  The power conditioner 4 converts power appropriately. The power conditioner 4 is connected between the photovoltaic power generation unit 3 and the first power path 21 (first connection unit 31). In the power conditioner 4, the power input side is connected to the solar power generation unit 3, and the power (DC power) output from the solar power generation unit 3 is input. The power conditioner 4 is configured to convert the DC power input from the solar power generation unit 3 into AC power, and to output the converted AC power.

  The 1st electric power sensor 11 detects the electric power of an installation location. The first power sensor 11 is installed on the distribution board 2 side (downstream side) with respect to the first connection portion 31 in the first power path 21. The first power sensor 11 is electrically connected to a fuel cell 5 described later. The first power sensor 11 is configured to transmit a detection result to the fuel cell 5.

  The fuel cell 5 generates power using a fuel such as hydrogen. The fuel cell 5 includes a solid oxide fuel cell (SOFC: Solid Oxide Fuel Cell), a control unit, and the like. The fuel cell 5 is connected to the middle part of the first power path 21 (hereinafter referred to as “second connection part 32”). The second connection portion 32 is disposed on the distribution board 2 side (downstream side) of the first power path 21 with respect to the first power sensor 11. The fuel cell 5 is electrically connected to the first power sensor 11. The fuel cell 5 is configured to be able to receive the detection result transmitted from the first power sensor 11.

  Further, the fuel cell 5 is configured to generate power based on a power generation plan to be described later and to output the generated power. The power generated by the fuel cell 5 is supplied to the distribution board 2 in preference to the power from other power supply sources (specifically, the commercial power source 100, the solar power generation unit 3, and the power storage device 6). Is done. The fuel cell 5 has a maximum generated power set to 700W. The fuel cell 5 includes a hot water storage unit (not shown). The fuel cell 5 can boil hot water in the hot water storage unit using heat generated during power generation.

  Further, the fuel cell 5 calculates information on the power supplied to the distribution board 2 (power consumption of the load, the same applies hereinafter) based on the information on the power generation performed by itself and the detection result from the first power sensor 11. (Acquired). The fuel cell 5 has a load following function capable of generating power based on the power consumption of the load. Further, the fuel cell 5 has a function of learning information related to power consumption of the load and information related to hot water supply in which the hot water of the hot water storage unit is used (hereinafter referred to as “learning function”).

  Further, the fuel cell 5 estimates a period (time zone, day of the week, etc.) where the power consumption of the load is relatively large based on the information learned by the learning function. The fuel cell 5 creates a power generation plan in consideration of the lifestyle of the resident of the house based on the estimated result. When the power generation plan is created, the fuel cell 5 generates power according to the power generation plan. That is, the fuel cell 5 can generate power at an optimal timing in consideration of the lifestyle of the resident of the house by following the power generation plan. The power generation plan is updated as appropriate based on information learned by the learning function.

  The 2nd electric power sensor 12 detects the electric power of an installation location. The second power sensor 12 is installed on the distribution board 2 side (downstream side) with respect to the second connection portion 32 in the first power path 21. Second power sensor 12 is electrically connected to power storage device 6 to be described later. Second power sensor 12 is configured to transmit the detection result to power storage device 6.

  The 3rd electric power sensor 13 detects the electric power of an installation location. The third power sensor 13 is installed between the fuel cell 5 and the first power path 21 (second connection portion 32). Third power sensor 13 is electrically connected to power storage device 6 to be described later. The third power sensor 13 is configured to be able to transmit the detection result to the power storage device 6.

  The power storage device 6 can charge and discharge electric power. The power storage device 6 can supply (discharge) the charged power to the load. The power storage device 6 is configured to be grid-connected and is operated by being connected to the commercial power supply 100 via the distribution board 2 or the like. The power storage device 6 includes a lithium ion battery (not shown), a time measuring unit that measures the date and time, a recording unit that records predetermined information, a control unit, and the like. The power storage device 6 is electrically connected to the second power sensor 12 and the third power sensor 13. The power storage device 6 is configured to be able to receive detection results from the second power sensor 12 and the third power sensor 13.

  In addition, the power storage device 6 is based on the detection result from the third power sensor 13 and relates to the power generated by the fuel cell 5 (for example, the amount of power generation, the date and time of power generation, the period of power generation, etc. Information). The power storage device 6 records the acquired information in the recording unit. Thus, the power storage device 6 maintains a history of the power generated by the fuel cell 5.

  In addition, the power storage device 6 is configured to be capable of load following operation in which discharge is performed and the amount of discharge is changed based on information on power consumption of the load. The power storage device 6 acquires information related to the power consumption of the load based on the information related to charging / discharging performed by itself and the detection result from the second power sensor 12. In the power storage device 6, the smallest electric power that can be discharged (minimum discharge power) is set to 100W. That is, the power storage device 6 does not discharge with power smaller than 100W. The minimum discharge power of the power storage device 6 is set in consideration of the discharge efficiency of the power storage device 6.

  The second power path 22 is a path through which power can be distributed. The second power path 22 is constituted by a conducting wire or the like. One end of the second power path 22 is connected to the distribution board 2. The other end of second power path 22 is connected to power storage device 6. In this way, the distribution board 2 and the power storage device 6 are configured to allow power to flow through the second power path 22 (that is, a path different from the first power path 21).

  Below, the supply mode of the electric power in the electric power supply system 1 is demonstrated easily.

  The electric power generated by the solar power generation unit 3 is output via the power conditioner 4 and supplied to the distribution board 2 via the first electric power path 21. Further, power from the commercial power source 100 and power generated by the fuel cell 5 are also supplied to the distribution board 2 via the first power path 21. Thus, the resident of the house can turn on the lighting or use the cooking utensil or the air conditioner. In this way, by supplying the power generated by the solar power generation unit 3 and the fuel cell 5 to the distribution board 2 (load), it is possible to reduce the purchase of power from the commercial power source 100 and to save power charges. it can.

  Moreover, the electric power generated by the solar power generation unit 3 and the electric power from the commercial power supply 100 are supplied to the power storage device 6 through the first electric power path 21 and the second electric power path 22 in an appropriate time zone. The electric power supplied to the power storage device 6 is charged in the power storage device 6. The electric power charged in the power storage device 6 is discharged from the power storage device 6 at a predetermined timing and supplied to the distribution board 2 via the second power path 22. In this way, for example, the power from the commercial power supply 100 can be charged in the power storage device 6 at midnight when the unit price is cheap, and can be used in the daytime when the demand for power in the house increases.

  Further, when electric power is discharged from the power storage device 6, predetermined electric power (50 W in the present embodiment) is purchased from the commercial power source 100. Thus, while power is being discharged from the power storage device 6, the power from the fuel cell 5 and the power storage device 6 is prevented from flowing backward to the commercial power source 100 by purchasing power from the commercial power source 100.

  Further, when the power consumption of the load is sufficiently covered by the power generated by the fuel cell 5 or the power discharged from the power storage device 6, the power generated by the solar power generation unit 3 flows backward to the commercial power source 100. It is possible to sell electricity. Thus, the resident of the house can obtain an economic merit.

  Below, the discharge of the electrical storage apparatus 6 is demonstrated in detail.

  As described above, for the power consumption of the load, the power generated by the fuel cell 5 is used in preference to the power discharged from the power storage device 6. Therefore, the electrical storage device 6 is discharged in consideration of the power generated by the fuel cell 5 and the power consumption of the load. In addition, the electrical storage apparatus 6 acquires the information regarding the power consumption of a load with the information regarding charging / discharging performed by itself, and the detection result from the 2nd electric power sensor 12. FIG. Therefore, when the power storage device 6 is not discharging by itself (the power from the power storage device 6 is not supplied to the distribution board 2), the power detected by the second power sensor 12 (first It can be determined that the power supplied to the distribution board 2 via the power path 21 is the power consumption of the load.

  Since the power storage device 6 uses the power generated by the fuel cell 5 with priority over the power consumption of the load, at least the power consumption of the load (that is, the power detected by the second power sensor 12) When a predetermined threshold, which will be described later, is exceeded, the battery can be discharged.

  Since the power storage device 6 uses the power generated by the fuel cell 5 with priority over the power consumption of the load, the power based on the value obtained by subtracting the power generated by the fuel cell 5 from the power consumption of the load. (Power based on the shortage of power generated by the fuel cell 5 with respect to the power consumption of the load) can be discharged.

  Hereinafter, the threshold value will be described in detail.

  The threshold value is a value used for determining whether or not the power storage device 6 is in a dischargeable state. The threshold value is set based on a history of electric power generated by the fuel cell 5 by the power storage device 6 (more specifically, the control unit of the power storage device 6 and the same hereinafter). More specifically, the threshold value is an average value of the power generation amount of the fuel cell 5 in a predetermined period in the same period of the previous year (for example, one month before and after the same period of the previous year). Calculated using the history of power. As described later, the threshold value is appropriately changed every predetermined period.

  In addition, when the power supply system 1 has just been introduced into the house (when the history is not sufficiently maintained), the same value as the maximum generated power of the fuel cell 5 is set as the threshold value. That is, in this embodiment, 700 W is set as the threshold value when the power supply system 1 has just been installed in a house.

  Below, the change of the threshold value in the electrical storage apparatus 6 is demonstrated using the flowchart of FIG.

  In step S <b> 101, the power storage device 6 records information acquired based on the detection result from the third power sensor 13. Thus, the power storage device 6 maintains a history of the power generated by the fuel cell 5.

  In step S102, the power storage device 6 determines whether or not it is time to change the threshold. In the present embodiment, the threshold value is changed every month (for example, on the first day of every month). In this way, the power storage device 6 determines that it is time to change the threshold when the date and time counted by the timing unit reaches midnight on the first day of every month.

  If the power storage device 6 determines that it is not time to change the threshold (the date and time counted by the timekeeping unit is not midnight per day) (No in step S102), the threshold is not changed, Recording of information acquired based on the detection result from the three power sensor 13 is continued (see step S101).

  On the other hand, when the power storage device 6 determines that it is time to change the threshold (the date and time counted by the timekeeping unit is midnight per day) (Yes in step S102), in step S103, A new threshold is calculated. Specifically, the power storage device 6 reads the history of the power generation amount of the fuel cell 5 in one month before and after the same period of the previous year from the recording unit, and calculates the average value of the power generation amount of the fuel cell 5 from the read history. calculate.

  In step S <b> 104, the power storage device 6 changes the threshold value based on the calculated average value of the power generation amount of the fuel cell 5. Specifically, the power storage device 6 sets the same value as the average value of the power generation amount as a new threshold value. For example, if the average value of the power generation amount is 400 W, the power storage device 6 sets the new threshold value to 400 W.

  In this manner, the threshold value in the power storage device 6 is appropriately changed every predetermined period.

  Hereinafter, in order to clarify the power supply mode in the power supply system 1 according to the present embodiment, a specific example relating to the discharge of the power storage device 96 in the power supply mode in the conventional power supply system 901 will be described with reference to FIG. A typical supply mode will be described.

  As shown in FIG. 6, a conventional power supply system 901 mainly includes a distribution board 92, a first power path 921, a first power sensor 911, a fuel cell 95, a second power sensor 912, and a power storage. A device 96 and a second power path 922. These are the distribution board 2, the first power path 21, the first power sensor 11, the fuel cell 5, the second power sensor 12, and the power storage device 6 in the power supply system 1 according to the present embodiment, respectively. , Corresponding to the second power path 22.

  In the conventional power supply system 901, when the power storage device 96 is discharged, the power supplied to the distribution board 92 via the first power path 921 is at least the maximum generated power (700 W) of the fuel cell 95. Is set to be larger than That is, when the detection result of the second power sensor 912 exceeds 700 W, the power storage device 96 can discharge the excess power. With such a configuration, the learning function of the fuel cell 95 is prevented from being hindered by the electric power discharged from the power storage device 96.

  Here, FIG. 6 shows a case where the power consumption of the load is 700 W and the power generated by the fuel cell 95 is 400 W, for example. In such a case, since the power (400 W) generated by the fuel cell 95 is insufficient with respect to the power consumption (700 W) of the load, the insufficient power (300 W) is purchased from the commercial power supply 100. Thus, when the insufficient power (300 W) is purchased from the commercial power supply 100, the power detected by the second power sensor 912 is 700 W. That is, the power storage device 96 determines that the power consumption of the load does not exceed the maximum generated power of the fuel cell 95 and does not discharge.

  Thus, in the conventional power supply system 901, in the case as shown in FIG. 6, since the power storage device 96 is not discharged, the amount of power purchased from the commercial power supply 100 may increase. That is, in the conventional power supply system 901, when the power generated by the fuel cell 95 is not the maximum generated power (700 W), the opportunity for discharging the power storage device 96 is limited, and the power supply system 901 can be purchased from the commercial power supply 100. There was a case where the amount of electricity increased.

  In contrast, in the power supply system 1 according to the present embodiment, the amount of power purchased from the commercial power supply 100 increases even when the power generated by the fuel cell 5 is not the maximum generated power (700 W). It is comprised so that it can suppress.

Below, the specific supply aspect at the time of discharge of the electrical storage apparatus 6 among the supply aspects of the electric power in the electric power supply system 1 is demonstrated.
In the following, for convenience of explanation, it is assumed that the solar power generation unit 3 does not generate power.

  First, in the following, with reference to FIG. 3, a power supply mode related to the discharge of the power storage device 6 when 700 W is set as the threshold (that is, when the power supply system 1 is just installed in the house). explain.

  Specifically, referring to FIG. 3, when 700 W is set as the threshold, for example, the power consumption of the load is 850 W, and the power generated by the fuel cell 5 is 700 W (maximum generated power). The power supply mode in this case will be described.

  In this case, first, as shown in FIG. 3A, a shortage occurs only with the power (700 W) generated by the fuel cell 5 with respect to the power consumption (850 W) of the load. Is purchased from the commercial power source 100.

  As described above, when the shortage of 150 W of electric power is purchased from the commercial power supply 100, 850 W of electric power combined with the electric power generated by the fuel cell 5 (700 W) is detected by the second power sensor 12. . When power of 850 W is detected by the second power sensor 12, the power storage device 6 determines that the power consumption (850 W) of the load exceeds the threshold value (700 W) and is in a dischargeable state.

  Further, as described above, the power discharged from the power storage device 6 is based on a value obtained by subtracting the power generated by the fuel cell 5 from the power consumption of the load. That is, in the case shown in FIG. 3, 150 W of power is discharged from the power storage device 6 as power based on a value obtained by subtracting the power (700 W) generated by the fuel cell 5 from the power consumption (850 W) of the load. It becomes possible.

  Note that, when the power storage device 6 is discharged as described above, for example, 50 W of power is purchased to prevent the power from flowing backward to the commercial power source 100. Therefore, 100 W obtained by subtracting 50 W of electric power purchased from the commercial power supply 100 from 150 W of electric power that can be discharged becomes electric power that is finally discharged from the power storage device 6. The power of 100 W is power that can be discharged by the power storage device 6 (the same value as the minimum discharge power of the power storage device 6).

  Thus, as shown in FIG. 3B, when the threshold is set to 700 W, the power consumption of the load is 850 W, and the power generated by the fuel cell 5 is 700 W (maximum generated power). In this case, 100 W of power is discharged from the power storage device 6, and 50 W of power is purchased from the commercial power source 100. Thus, the amount of power purchased from the commercial power supply 100 is relatively small.

  Next, with reference to FIG. 4, a power supply mode related to the discharge of the power storage device 6 when 400 W is set as the threshold (that is, when the threshold is changed to a new threshold) will be described.

  Specifically, referring to FIG. 4, when 400 W is set as the threshold, for example, the power consumption of the load is 550 W, and the power generated by the fuel cell 5 is 400 W (less than the maximum generated power). The power supply mode in the case of (power) will be described.

  In this case, first, as shown in FIG. 4 (a), a shortage occurs only with the power (400W) generated by the fuel cell 5 with respect to the power consumption (550W) of the load. Is purchased from the commercial power source 100.

  As described above, when the shortage of 150 W of electric power is purchased from the commercial power source 100, 550 W of electric power combined with the electric power (400 W) generated by the fuel cell 5 is detected by the second power sensor 12. . When power of 550 W is detected by the second power sensor 12, the power storage device 6 determines that the power consumption (550 W) of the load exceeds the threshold value (400 W), and is in a dischargeable state.

  Further, as described above, the power discharged from the power storage device 6 is based on a value obtained by subtracting the power generated by the fuel cell 5 from the power consumption of the load. That is, in the case shown in FIG. 4, 150 W of power is discharged from the power storage device 6 as power based on a value obtained by subtracting the power (400 W) generated by the fuel cell 5 from the power consumption (550 W) of the load. It becomes possible.

  Note that, when the power storage device 6 is discharged as described above, for example, 50 W of power is purchased to prevent the power from flowing backward to the commercial power source 100. Therefore, 100 W obtained by subtracting 50 W of electric power purchased from the commercial power supply 100 from 150 W of electric power that can be discharged becomes electric power that is finally discharged from the power storage device 6. The power of 100 W is power that can be discharged by the power storage device 6 (the same value as the minimum discharge power of the power storage device 6).

  Thus, as shown in FIG. 4B, when 400 W is set as the threshold, the power consumption of the load is 550 W, and the power generated by the fuel cell 5 is 400 W (maximum generated power). In this case, 100 W of power is discharged from the power storage device 6, and 50 W of power is purchased from the commercial power source 100. Thus, the amount of power purchased from the commercial power supply 100 is relatively small.

As described above, the power supply system 1 is
A fuel cell 5 capable of supplying generated power to a load;
When the power consumption of the load exceeds a predetermined threshold, the power storage device 6 capable of discharging the charged power to the load;
A power storage device 6 (more specifically, the control unit of the power storage device 6) (control means) that stores a history of the power generation amount of the fuel cell 5 and changes the predetermined threshold based on the stored history;
It comprises.

With such a configuration, an increase in the amount of power purchased from the commercial power source 100 can be suppressed.
Specifically, since the threshold value is changed based on the history of the power generation amount of the fuel cell 5, for example, the threshold value can be small during a period when the power generation amount of the fuel cell 5 is considered to be relatively small. Therefore, in such a period, for example, the chance of discharging the power storage device 6 can be increased as compared with the conventional power supply system 901 shown in FIG. 6, and the amount of power purchased from the commercial power supply 100 is increased. Can be suppressed.

In the power supply system 1,
The power storage device 6 (more specifically, the control unit of the power storage device 6) (control means)
An average value of the power generation amount of the fuel cell 5 is calculated from the stored history, and the predetermined threshold value is changed based on the calculated average value.

With such a configuration, an increase in the amount of power purchased from the commercial power source 100 can be suppressed.
Specifically, when the power consumption of the load exceeds the threshold value that has been changed based on the calculated average value, the power storage device 6 discharges the excess power, so the discharge of the power storage device 6 Can be based on more past performance. In this way, for example, compared to the conventional power supply system 901 shown in FIG. 6, the chance of discharging the power storage device 6 can be increased based on the past results, and the amount of power purchased from the commercial power supply 100 is increased. Can be suppressed.

In the power supply system 1,
The power storage device 6 includes:
When the power consumption of the load exceeds the predetermined threshold, power based on a value obtained by subtracting the power generated by the fuel cell 5 from the power consumption of the load is discharged.

With such a configuration, it is possible to prevent the power generation of the fuel cell 5 from being hindered.
Specifically, for example, as shown in FIGS. 3B and 4B, even when 100 W of power is discharged from the power storage device 6 as the power based on the subtracted value, the second The power detected from the power sensor 12 does not become smaller than the power generated by the fuel cell 5. That is, the power supplied to the distribution board 2 via the first power path 21 is prevented from becoming smaller than the power generated by the fuel cell 5 at the beginning, and thus the power generation of the fuel cell 5 is hindered. Can be prevented.

  Note that the case where the power generated by the fuel cell 5 in the present embodiment is smaller than the maximum generated power (for example, 400 W shown in FIG. 4), for example, because the demand for hot water supply is small, the fuel cell It is assumed that 5 cannot generate the maximum generated power. In other words, the power supply system 1 can be efficiently operated by changing the threshold value when there is little demand for hot water supply (for example, a season other than the winter season).

The power supply system 1 according to the present embodiment is an embodiment of the power supply system.
The fuel cell 5 according to this embodiment is an embodiment of a fuel cell.
The power storage device 6 according to this embodiment is an embodiment of the power storage device.
Moreover, the control part of the electrical storage apparatus 6 which concerns on this embodiment is one Embodiment of a control means.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said structure, A various change is possible within the range of the invention described in the claim.

  Moreover, although the electric power supply system 1 which concerns on this embodiment shall be employ | adopted as a house, it is not limited to this. The power supply system can be employed in various facilities such as hospitals and accommodation facilities.

  Further, 700 W of the maximum generated power of the fuel cell 5 according to the present embodiment, 100 W of the minimum discharge power of the power storage device 6, and 50 W of the purchased power from the commercial power source 100 when the power is discharged from the power storage device 6 are This is an embodiment and is not limited to these values.

  In the description of the present embodiment, for convenience, the solar power generation unit 3 is not generating power, but the solar power generation unit 3 may be generating power. In this way, when the solar power generation unit 3 is generating power and the power generated by the fuel cell 95 is insufficient with respect to the power consumption of the load, A part (or all) of the electric power generated by the photovoltaic unit 3 is used.

  Although the threshold value according to the present embodiment is the average value of the power generation amount of the fuel cell 5 in a predetermined period in the same period of the previous year (for example, one month before and after the same period of the previous year), the threshold value is not limited thereto. Absent.

  For example, the threshold value may be an average value of the power generation amount of the fuel cell 5 in the most recent month, week, or day instead of one month before and after the same period of the previous year. Further, the threshold value need not be the same as the average value as long as it is based on the calculated average value, and may be a value slightly larger (for example, about 50 W) than the average value. Thus, if the threshold value is set to a value slightly larger than the average value, even if the load power consumption is slightly larger than the average value, the fuel cell 5 generates the power consumption of the load. An increase in the amount of power purchased from the commercial power source 100 can be suppressed as much as possible while being covered with electric power.

  Further, the threshold value is not limited to the calculated average value, but may be set based on the history of the power generation amount of the fuel cell 5. For example, the threshold value may be set according to the analysis result by analyzing the tendency of increase or decrease of the power generation amount based on the history of the power generation amount of the fuel cell 5. Moreover, for example, when the threshold value is changed every day, the threshold value may be set based on the power generation plan of the fuel cell 5 on the next day.

  The threshold value is changed every month (for example, the first day of every month). However, the threshold value may be changed every year, every season, every week, every day, or the like.

  Moreover, in this embodiment, although the threshold value shall be changed by the control part of the electrical storage apparatus 6, it is not limited to this. For example, the power supply system may include a home energy management system (hereinafter referred to as “HEMS”), and the threshold value may be changed by the HEMS. This will be specifically described below.

  FIG. 5 is a block diagram showing another example of the configuration of the power supply system 1 according to the present embodiment. In the another example, the power supply system 1 includes a HEMS 7.

  The HEMS 7 is a system that controls electric equipment used in a house. The HEMS 7 can visualize the power consumption of the load using a mobile terminal or the like, and can notify the visualized information to a resident in the house. The HEMS 7 is electrically connected to the fuel cell 5 and the power storage device 6. The HEMS 7 can acquire and manage (control) information related to the operation of the fuel cell 5 and the power storage device 6 and information related to electric power.

  In such a configuration, the HEMS 7 can acquire and store (hold) the history of the power generated by the fuel cell 5. Moreover, HEMS7 can acquire the information regarding the power consumption of load. Thus, the HEMS 7 calculates the threshold value and determines whether or not the power storage device 6 is in a dischargeable state using the threshold value. When the HEMS 7 determines that the power storage device 6 is in a dischargeable state, the HEMS 7 controls the power storage device 6 to discharge.

According to such a configuration, the management of information in the house and the control of various electric devices can be performed in a unified manner using the HEMS 7, so that the operation of the power supply system 1 can be performed more efficiently.
Specifically, the fuel cell 5 generally has a period during which power generation is stopped due to detection of a gas leak that is a fuel for power generation and the life. Accordingly, the HEMS 7 acquires and stores (holds) the history of the power generated by the fuel cell 5 and acquires information on the power consumption of the load, thereby more efficiently operating the power supply system 1. It can be carried out.

  When the power supply system 1 includes the HEMS 7, the threshold value is not used to determine whether or not the power storage device 6 is in a dischargeable state, but the HEMS 7 generates power from the power consumption of the load by the fuel cell 5. The electric power based on the value obtained by subtracting the generated electric power can be discharged from the power storage device 6. With such a configuration, the operation of the power supply system 1 can be performed more efficiently.

DESCRIPTION OF SYMBOLS 1 Power supply system 2 Distribution board 5 Fuel cell 6 Power storage device 100 Commercial power supply

Claims (3)

A fuel cell capable of supplying generated power to a load;
When the power consumption of the load exceeds a predetermined threshold, a power storage device capable of discharging the charged power to the load;
Control means for storing a history of the power generation amount of the fuel cell, and changing the predetermined threshold based on the stored history;
A power supply system comprising: The control means includes
Calculating an average value of the power generation amount of the fuel cell from the stored history, and changing the predetermined threshold based on the calculated average value;
The power supply system according to claim 1. The power storage device
Discharging power based on a value obtained by subtracting the power generated by the fuel cell from the power consumption of the load when the power consumption of the load exceeds the predetermined threshold;
The power supply system according to claim 1 or 2.

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