JP7617796B2 - Power supply management system, fuel cell device and charging/discharging device - Google Patents

Description

The present invention relates to a power supply management system that includes a power supply device that is installed in each of a number of facilities and is capable of outputting electric power, and a management device that can communicate with the multiple power supply devices from a remote location outside the facilities, as well as a fuel cell device and a charge/discharge device that serve as power supplies used in the power supply management system.

In addition to conventional large-scale power plants, power supply devices such as power generation devices and charge/discharge devices installed in facilities such as homes and offices are also connected to the power system. Power load devices installed in the facilities are also connected to the power system. The power supply devices and power load devices can be used to increase or decrease the power at the receiving point of the facility, thereby contributing to the adjustment of the balance of power supply and demand in the power system. In recent years, under the concept of a virtual power plant (VPP), attempts have been made to provide functions equivalent to those of a power plant by controlling the operation of consumer-side energy resources such as the above-mentioned power supply devices and power load devices installed in the consumer's facility. The power at the receiving point of a facility includes both the power received from the power system to the facility and the reverse flow power from the facility to the power system.
Patent Literature 1 (JP 2019-58007 A) describes a power management system including a power supply device installed in each of a plurality of facilities and a management device capable of communicating with the plurality of power supply devices. The management device assigns output commands to each power supply device based on a priority order previously set for each power supply device.

JP 2019-58007 A

When increasing or decreasing the power at the receiving point of a facility by increasing or decreasing the output power of a power supply device, if the load power of the facility's power load device becomes greater than the output power of the power supply device, power will be purchased from the power grid. However, in Patent Document 1, the load power of the facility in which each power supply device is installed is not taken into consideration when allocating output commands to each power supply device. Therefore, in the method of allocating output commands to each power supply device based on a preset priority as described in Patent Document 1, power will be purchased from the power grid in the facility in which each power supply device is installed, which may result in significant financial losses.

The present invention was made in consideration of the above problems, and its purpose is to provide a power management system in which commands are issued to a power supply device taking into account financial losses at the facility, and a fuel cell device and a charge/discharge device as power supplies used in the power management system.

A characteristic configuration of a power supply management system according to the present invention for achieving the above object is a power supply management system including power supply devices installed in each of a plurality of facilities and capable of outputting electric power, and a management device capable of communicating with the plurality of power supply devices from a remote location outside the facilities,
The power supply device includes a power supply unit connected to a power grid,
a power load device installed in the facility is configured to receive power supply from at least one of the power supply device and the power system installed in the facility;
The management device performs a command transmission process for transmitting output control commands to the plurality of power supply devices to determine output power of the power supply devices;
When the power supply device receives the output control command from the management device, the power supply device operates to supply an output power determined based on the output control command during a control period that is the subject of the output control command;
In the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility that is unlikely to cause a large financial loss when the power supply device operates in accordance with the output control command during the control target period, among the plurality of power supply devices ;
When the management device sends an output control command to reduce the output power of the power supply unit during the command transmission process, the management device determines that the greater the excess power derived by subtracting the load power of the power load device from the output power of the power supply unit in the facility, the less likely the financial loss at the facility will be .

The larger the excess power derived by subtracting the load power of the power load devices from the output power of the power supply devices in a facility, the greater the leeway the facility has to reduce the output power of the power supply devices while avoiding purchasing power from the power grid.
Therefore, with this characteristic configuration, it is possible to provide a power management system that determines that the greater the excess power, the less likely it is that financial losses will occur at the facility if the power supply device operates in accordance with an output control command during the control period, and that prioritizes sending output control commands to the power supply devices installed in the facility .

A characteristic configuration of a power supply management system according to the present invention for achieving the above object is a power supply management system including power supply devices installed in each of a plurality of facilities and capable of outputting electric power, and a management device capable of communicating with the plurality of power supply devices from a remote location outside the facilities,
The power supply device includes a power supply unit connected to a power grid,
a power load device installed in the facility is configured to receive power supply from at least one of the power supply device and the power system installed in the facility;
The management device performs a command transmission process for transmitting output control commands to the plurality of power supply devices to determine output power of the power supply devices;
When the power supply device receives the output control command from the management device, the power supply device operates to supply an output power determined based on the output control command during a control period that is the subject of the output control command;
In the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility that is unlikely to cause a large financial loss when the power supply devices operate in accordance with the output control command during the control target period, among the plurality of power supply devices;
In the command transmission process, when the management device sends an output control command to reduce the output power of the power supply unit, it determines that the greater the output power of the power supply unit in the facility, the less likely the financial loss at the facility will be.

The higher the output power of the power supply device, i.e., the closer the output power is to the rated output, the less likely it is that monetary losses will be large even if the output power is reduced, due to efficient operation. Also, the higher the output power of the power supply device, the more likely it is that the facility will be able to reduce the output power of the power supply device while avoiding purchasing power from the power grid, even if the output power is reduced.
Therefore, with this characteristic configuration, a power management system can be provided in which, based on the determination that the greater the output power of a power supply device, the less likely it is that financial losses will be caused to the facility if the power supply device operates in accordance with an output control command during the control period, and output control commands are sent preferentially to power supplies installed in the facility.

Another characteristic configuration of the power supply management system of the present invention is that, when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates output reduction amounts to be commanded to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted, the post-command excess power derived by subtracting the load power of the power load device from the post-command output power after the output power of the power supply device is reduced in accordance with the output control command becomes zero or greater and the post-command output power becomes the same or close to a value of the other power supply devices.

The larger the post-command output power after the output power of the power supply device in the facility is reduced in response to the output control command, i.e., the closer the post-command output power is to the rated output, the more efficiently the power supply device is operating, and the less likely it is to incur a large financial loss. Also, the larger the post-command output power after the output power of the power supply device in the facility is reduced in response to the output control command, the more likely it is that the facility will be able to reduce the output power of the power supply device while avoiding purchasing power from the power grid.
Therefore, in this characteristic configuration, in multiple facilities to which an output control command is sent, the output reduction range to be commanded to multiple power supply devices is allocated so that the post-command excess power derived by subtracting the load power of the power load device from the post-command output power after the output power of the power supply device is reduced in response to the output control command is zero or greater and the post-command output power is the same or close to the value of the other power supply devices.

Another characteristic configuration of the power supply management system of the present invention is that, when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates the output reduction amount to be commanded to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted, the post-command excess power derived by subtracting the load power of the power load device from the post-command output power after the output power of the power supply device is reduced in accordance with the output control command is zero or more.

According to the above characteristic configuration, by allocating the output reduction range to be commanded to multiple power supply devices so that the post-command excess power after the output power of the power supply device is reduced in response to an output control command is zero or more, the facility in which the power supply device is installed is more likely to be able to avoid purchasing electricity from the power grid.

Another characteristic configuration of the power management system of the present invention is that, when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates output reduction amounts to be commanded to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted, the post-command excess power derived by subtracting the load power of the power load device from the post-command output power of the power supply device in the facility after the output power of the power supply device has been reduced in accordance with the output control command is equal to or greater than a predetermined value greater than zero.

According to the above-described characteristic configuration, by allocating the output reduction range to be commanded to multiple power supply devices so that the post-command excess power after the output power of the power supply device is reduced in response to an output control command is equal to or greater than a predetermined value greater than zero, the facility in which the power supply devices are installed is more likely to be able to avoid purchasing electricity from the power grid.

Another characteristic configuration of the power management system of the present invention is that, in the command transmission process, if the post-command excess power after reducing the output power of the power supply device in accordance with the output control command in all of the multiple facilities becomes less than zero, the management device commands an output reduction amount such that the post-command excess power of all of the multiple facilities becomes equal to each other.

According to the above-mentioned characteristic configuration, the excess power of the multiple facilities is equal to each other and is less than zero, i.e., the amount of power purchased from the power grid by the multiple facilities is equal to each other. As a result, the monetary loss due to the power purchase by each facility is equalized.

In yet another characteristic configuration of the power supply management system according to the present invention, when transmitting the output control command to increase the output power of the power supply device in the command transmission process, the management device transmits the output control command preferentially to a power supply device installed in the facility where a financial benefit is likely to be large if the output power of the power supply device is increased in response to the output control command during the control target period, among the multiple power supply devices;
When the management device sends an output control command to increase the output power of the power supply unit in the command transmission process, it determines that the smaller the excess power derived by subtracting the load power of the power load unit from the output power of the power supply unit in the facility, the greater the likelihood of the financial benefit in the facility.

Increasing the output power of the power supply may result in a greater financial benefit by allowing the facility to avoid purchasing electricity from the power grid. Also, the greater the output power of the power supply, i.e., the closer the output power is to the rated output, the greater the financial benefit may be due to more efficient operation.
Therefore, in this characteristic configuration, it is determined that the smaller the excess power derived by subtracting the load power of the power load device from the output power of the power supply device in the facility, the greater the financial benefit to the facility is likely to be, and an output control command is sent preferentially to the power supply device installed in the facility.

In yet another characteristic configuration of the power supply management system according to the present invention, when transmitting the output control command to increase the output power of the power supply device in the command transmission process, the management device transmits the output control command preferentially to a power supply device installed in the facility where a financial benefit is likely to be large if the output power of the power supply device is increased in response to the output control command during the control target period, among the multiple power supply devices ;
When the management device sends an output control command to increase the output power of the power supply unit in the command transmission process, the management device determines that the smaller the output power of the power supply unit in the facility, the greater the financial benefit in the facility is likely to be.

Increasing the output power of the power supply may result in a greater financial benefit by allowing the facility to avoid purchasing electricity from the power grid. Also, the greater the output power of the power supply, i.e., the closer the output power is to the rated output, the greater the financial benefit may be due to more efficient operation.
Therefore, in this characteristic configuration, it is determined that the smaller the output power of the power supply device in the facility, the greater the financial benefit to the facility is likely to be, and an output control command is preferentially sent to the power supply device installed in the facility .

Another characteristic configuration of the power management system according to the present invention is that the management device
In the command transmission process, when transmitting the output control command to reduce the output power of the power supply device, the output control command is preferentially transmitted to the power supply device provided in the facility for which the cumulative total of the monetary loss caused by the command transmission process performed during a predetermined period in the past is small;
In the command transmission process, when an output control command to increase the output power of the power supply device is sent, the output control command is preferentially sent to the power supply device installed in the facility where the cumulative financial loss caused by the command transmission process performed during the specified period in the past is large.

According to the above characteristic configuration, when multiple power supply devices are operated in response to an output control command to reduce or increase the output power, the cumulative monetary losses of each of the multiple power supply devices are equalized.

The characteristic configuration of the fuel cell device according to the present invention for achieving the above object is that it has the functions of the power supply device used in the above power supply management system, and the power supply unit has a fuel cell.

The above characteristic configuration makes it possible to provide a fuel cell device that has the functionality of a power supply device used in a power supply management system that issues commands to the power supply device while taking into account financial losses at the facility.

The characteristic configuration of the charge/discharge device according to the present invention for achieving the above object is that it has the functions of the power supply device used in the above power supply management system, and the power supply unit has a charge/discharge unit.

The above characteristic configuration makes it possible to provide a charge/discharge device that has the functionality of a power supply device used in a power supply management system that issues commands to the power supply device while taking into account financial losses at the facility.

FIG. 2 is a diagram showing the relationship between facilities, a management device, and an aggregation coordinator. FIG. 1 is a diagram showing an example of a facility configuration. FIG. 2 is a diagram illustrating a control period and a non-control period. 1 is a graph showing a curve f(x) that allows one to identify the additional operating cost per minute caused by the command transmission process.

Fig. 1 is a diagram showing the relationship between a facility 20 in which a fuel cell device 10 and a power load device 4 are provided, a management device 30, and an aggregation coordinator 40. Fig. 2 is a diagram showing an example of the configuration of the facility 20. The power supply management system comprises a fuel cell device 10 that is installed in each of a plurality of facilities 20 and capable of outputting power, and a management device 30 that is capable of communicating with the plurality of fuel cell devices 10 from a remote location outside the facility 20. Note that the number of management devices 30 and the number of facilities 20 shown in Fig. 1 can be changed as appropriate.
The fuel cell device 10 corresponds to the "power supply device" of the present invention.

The management device 30, also known as a resource aggregator, is an operator that controls the consumer-side energy resources by transmitting control information to the fuel cell device 10 and the power load device 4 as consumer-side energy resources to the facility 20 that has concluded a VPP (Virtual Power Plant) service contract. The aggregation coordinator 40 is an operator that bundles the amount of power controlled by each management device 30 and trades power with general electricity transmission and distribution operators and retail electricity operators in the electricity trading market, etc.

The management device 30 sequentially collects and stores power information such as the output power of the fuel cell device 10, the load power of the power load device 4, and the power receiving point power at the facility 20 from multiple facilities 20. In this embodiment, the term "load power of the power load device 4" refers to the total load power of all the power load devices 4 installed in the facility 20. The management device 30 predicts the power that can be supplied from each facility 20 in a specified future time period and transmits it to the aggregation coordinator 40. This supplyable power is an adjustment margin such as the ability to increase or decrease the power receiving point power of the facility 20. In this embodiment, "increasing the power receiving point power" means increasing the power received from the power system 1 to the power line 2, or decreasing the reverse flow power from the power line 2 to the power system 1, and "reducing the power receiving point power" means decreasing the power received from the power system 1 to the power line 2, or increasing the reverse flow power from the power line 2 to the power system 1.

For example, in order to increase the receiving point power of the facility 20, it is sufficient to at least either reduce the output power of the fuel cell device 10 or increase the load power of the power load device 4. Therefore, the increase-side adjustment margin when increasing the receiving point power of the facility 20 indicates how much margin there is for reducing the output power of the fuel cell device 10 and how much margin there is for increasing the load power of the power load device 4. Also, in order to decrease the receiving point power of the facility 20, it is sufficient to at least either increase the output power of the fuel cell device 10 or reduce the load power of the power load device 4. Therefore, the decrease-side adjustment margin when decreasing the receiving point power of the facility 20 indicates how much margin there is for increasing the output power of the fuel cell device 10 and how much margin there is for decreasing the load power of the power load device 4.

The management device 30 also determines the baseline power receiving point power for the multiple facilities 20 that it manages. This baseline power receiving point power corresponds to the total power receiving point power of each facility 20 predicted when each facility 20 is not allowed to provide adjustment capacity, etc. (i.e., adjustment capacity provided to the electricity transmission and distribution company and supply capacity provided to retailers, etc.).

The aggregation coordinator 40 aggregates the available electricity received from each management device 30 and trades electricity with general electricity transmission and distribution companies and retail electricity suppliers by bidding on electricity trading markets such as the supply and demand adjustment market, the wholesale electricity market, and the capacity market. When the aggregation coordinator 40 receives a supply command for adjustment capacity, etc. for a specified future control period from the general electricity transmission and distribution company or retail electricity supplier with which it has traded, it distributes and transmits the adjustment capacity, etc. specified in the supply command to each management device 30.

When the management device 30 receives a supply command from the aggregation coordinator 40, it distributes and transmits the adjustment power, etc. specified in the supply command to each facility 20. As a result, in each facility 20, the fuel cell device 10 and the power load device 4 as consumer-side energy resources are controlled during a specified future control period, and adjustment power, etc. is supplied such that the receiving point power of the facility 20 increases or decreases compared to the case where the control is not performed.

The facility 20 is provided with a fuel cell device 10 as a power supply device, and a power load device 4. The fuel cell device 10 and the power load device 4 are connected to a power line 2 that is linked to the power system 1. A power meter 3 that measures the power at the receiving point of the facility 20 is installed on the power line 2. Note that while Figures 1 and 2 show an example in which one fuel cell device 10 is installed as a power supply device, the number of installed power supplies can be changed as appropriate.

Information about the receiving point power measured by the power meter 3 is transmitted to the management device 30 via the gateway 5 and the router 6. For example, information about the receiving point power is transmitted to the management device 30 at a predetermined timing, such as every 10 seconds.

The power load device 4 is a variety of devices, such as lighting devices and air conditioning devices, and can receive power supply from at least one of the fuel cell device 10 and the power system 1 installed in the facility 20.

The fuel cell device 10 includes a fuel cell unit 12 as a power source unit connected to the power grid 1, a power conversion unit 11 that converts the power generated by the fuel cell unit 12 to a predetermined voltage, frequency, and phase and supplies it to the power line 2, a fuel cell control unit 13 that controls the operation of the fuel cell unit 12 and the power conversion unit 11, and a memory unit 14 that stores information handled by the fuel cell device 10. The fuel cell device 10 may also include a fuel reformer that generates hydrogen, which is the fuel gas for the fuel cell unit 12.

In this way, a fuel cell device 10 can be realized that has the functions of a power supply device used in a power supply management system and has a power supply unit equipped with a fuel cell unit 12.

The fuel cell control unit 13 can adjust the output power from the fuel cell device 10 to the power line 2 between a predetermined upper limit output power and a predetermined lower limit output power. For example, the fuel cell control unit 13 can maintain the output power of the fuel cell device 10 at the upper limit output power and operate it continuously. The fuel cell control unit 13 can also operate the fuel cell device 10 so that its output power follows the load power of the power load device 4. For example, the fuel cell control unit 13 can operate the fuel cell device 10 so that its output power follows the load power of the power load device 4 by adjusting the output power of the fuel cell device 10 so that the power measured by the power measurement unit (i.e., the power supplied from the power system 1) becomes zero or close to zero.

The fuel cell control unit 13 has information about the output power supplied from the power conversion unit 11 to the power line 2 and information about the power measured by the power measurement unit 8, so it can derive the load power (= output power + measured power) of the power load device 4. When the sign of the measured power by the power measurement unit 8 is positive, it means that the load power is greater than the output power of the fuel cell device 10, and when the sign of the measured power by the power measurement unit 8 is negative, it means that the output power of the fuel cell device 10 is greater than the load power.

The fuel cell device 10 is connected to a remote control 7 that is operated by users of the facility 20 when issuing commands to the fuel cell device 10. Information about the output power and load power of the fuel cell device 10 is transmitted to the management device 30 via the remote control 7 and the router 6. For example, information about the output power and load power of the fuel cell device 10 is transmitted to the management device 30 at a predetermined timing, such as once every minute.

As described above, the management device 30 performs a command transmission process to transmit output control commands that determine the output power of the fuel cell devices 10 to the multiple fuel cell devices 10. When the fuel cell devices 10 receive an output control command from the management device 30, they operate in a first operating mode that aims to supply output power determined based on the output control command during a controlled period that is the subject of the output control command, and operate in a second operating mode that is different from the first operating mode during a non-controlled period that is outside the controlled period.

The second operating mode is an operating mode that is preset in the multiple fuel cell devices 10. Alternatively, the management device 30 can transmit an operating mode control command that determines the second operating mode to the multiple fuel cell devices 10, and the fuel cell devices 10 determine the second operating mode according to the operating mode control command received from the management device 30. For example, the second operating mode is an operation that maintains the output power of the fuel cell device 10 at an upper limit output power, an operation that causes the output power of the fuel cell device 10 to follow the load power of the power load device 4, etc.

Figure 3 is a diagram that shows a schematic diagram of a controlled period and a non-controlled period. In the example shown in Figure 3, the control information (output control command) specifies the period from 12:00 to 15:00 as the controlled period. Therefore, this fuel cell device 10 operates in the first operating mode during the controlled period from 12:00 to 15:00, and operates in the second operating mode during the other non-controlled periods.

When the fuel cell device 10 receives an output control command from the management device 30, it aims to supply output power determined based on the output control command during the control period covered by the output control command. However, when increasing or decreasing the output power of the fuel cell device 10 to increase or decrease the power receiving point power of the facility 20, if the load power of the power load device 4 of the facility 20 becomes greater than the output power of the fuel cell device 10, power purchase from the power grid 1 will occur, and there is a possibility of a large financial loss. Therefore, in the command transmission process, the management device 30 preferentially transmits an output control command to a fuel cell device 10 installed in a facility 20 that is less likely to incur a large financial loss if it operates in accordance with the output control command during the control period, among the multiple fuel cell devices 10.

Below, an example of a method in which the management device 30 determines which facility 20 is unlikely to experience a large financial loss and determines which power supply device to send an output control command to. For example, in the command transmission process, when the management device 30 transmits an output control command to reduce the output power of the power supply device, the greater the excess power derived by subtracting the load power of the power load device 4 from the output power of the power supply device in the facility 20, the less likely the financial loss in the facility 20 is to be large. Alternatively, in the command transmission process, when the management device 30 transmits an output control command to reduce the output power of the power supply device, the greater the output power of the power supply device in the facility 20, the less likely the financial loss in the facility 20 is to be large. In the following description, a case in which the management device 30 transmits an output control command to five power supplies A, B, C, D, and E realized by, for example, a fuel cell device 10 is described. Also, assume that one power supply unit is installed in one facility 20, and that each of power supply units A, B, C, D, and E can adjust the output power to the power line 2 between an upper limit output power (0.7 kW) and a lower limit output power (0.05 kW).

[Example of determination method 1]
Example judgment method 1 is a case in which, as shown in Tables 1 and 2 below, when the management device 30 sends an output control command to reduce the output power of the power supply device during the command sending process, it judges that the greater the excess power derived by subtracting the load power of the power load device 4 from the output power of the power supply device in the facility 20, the less likely it is that financial losses will occur in the facility 20.

The larger the excess power (= output power - load power), the greater the margin for reducing the output power of the power supply device in the facility 20 while avoiding purchasing power from the power grid 1. In other words, if the output power is reduced within the range of the reduction margin (without power purchase) listed in Table 1, the facility 20 will not incur a financial burden due to power purchase, so it can be said that financial losses are unlikely to be large. Therefore, in the example of Table 1, the management device 30 prioritizes commanding an output reduction width that will result in zero or more excess power after the command after reducing the output power of the power supply device in response to the output control command. Specifically, the management device 30 allocates 0.1 kW each of the output power reduction of 0.2 kW to the power supply device A and the power supply device B within a range in which no power purchase occurs among the power supply devices A, B, D, and E in which the excess power (= output power - load power) is zero or more, that is, the reduction margin (without power purchase) exists that changes the output power in a negative direction without generating purchased power.

As in the case shown in Table 1, the greater the excess power (= output power - load power), the greater the leeway the facility 20 has to reduce the output power of the power supply unit while avoiding purchasing power from the power grid 1. In other words, if the output power is reduced within the range of the reduction margin (no power purchases), the facility 20 does not incur a financial burden due to power purchases, so it can be said that financial losses are unlikely to be large. Therefore, in the example of Table 2, the management device 30 allocates a total output power reduction of 0.2 kW equally to power supply units A, B, D, and E, which have excess power (= output power - load power) greater than zero, i.e., power reduction margin (no power purchases) that changes the output power in a negative direction without generating purchased power, by 0.05 kW each.

[Example of determination method 2]
Determination method example 2 is a case in which the management device 30 prioritizes, in the command transmission process, commanding an output reduction width such that the post-command excess power (=output power-load power) after reducing the output power of the power supply device in response to an output control command is equal to or greater than a predetermined value α that is greater than zero, as shown in the following Table 3. In other words, an output reduction width is specified such that the post-command excess power (=output power-load power) is equal to or greater than a predetermined value α that is greater than zero.

By prioritizing the command of an output reduction amount that will result in the post-command excess power after the output power reduction being equal to or greater than a predetermined value greater than zero, the facility 20 in which the power supply device is installed is more likely to be able to avoid purchasing electricity from the power grid 1.
In the case of Table 3, power supply B has an output power of 0.45 kW and a load power of 0.25 kW, so that the excess power (= output power - load power = 0.2 kW) is 0.1 kW larger than the predetermined value α (= 0.1 kW). In comparison, the excess power of power supplies A, D, and E is the same as the predetermined value α. Therefore, for power supply B, an output reduction width of 0.1 kW is preferentially allocated so that the post-command excess power (0.1 kW) after the output power is reduced is equal to or greater than the predetermined value α (= 0.1 kW) which is greater than zero. In addition, in the example of Table 3, the remaining output reduction width of 0.1 kW is allocated to power supply A.

In the case of Table 4, power supply B has an output power of 0.45 kW and a load power of 0.25 kW, so the excess power (= output power - load power = 0.2 kW) is 0.1 kW greater than the specified value α (= 0.1 kW). In other words, power supply B has a reduction margin (without purchasing power) of 0.2 kW that changes the output power in a negative direction without generating purchased power, and this value is 0.1 kW greater than the specified value α (= 0.1 kW). In comparison, the excess power of power supplies A, D, and E is the same as the specified value α. Therefore, for power supply B, an output reduction width of 0.1 kW is preferentially allocated so that the post-command excess power (0.1 kW) after reducing the output power is equal to or greater than the specified value α (= 0.1 kW) that is greater than zero. In addition, in the example of Table 4, the remaining output reduction width: 0.1 kW is allocated equally to the power supply devices A, B, D, and E that have excess power, with 0.025 kW each. As a result, an output reduction width: 0.125 kW is allocated to power supply device B, and an output reduction width: 0.025 kW is allocated to each of power supply devices A, D, and E.

[Example of determination method 3]
An example of the judgment method 3 is a case where, in the command transmission process, the management device 30 commands an output reduction amount such that the post-command excess power of all of the multiple facilities 20 becomes equal to each other when the post-command excess power (= output power - load power) after reducing the output power of the power supply device in accordance with an output control command in all of the multiple facilities 20 becomes less than zero, as shown in Table 5 below.

As shown in Table 5, although a total output power reduction of 0.8 kW is required, the reduction margin (without purchasing power) for changing the output power in a negative direction without generating purchased power is 0.5 kW for power supply devices A, B, C, D, and E in total. Therefore, in all of the multiple facilities 20, the post-command excess power after the output power of the power supply devices is reduced in response to the output control command is less than zero. In other words, purchased power is generated in at least one facility 20.

In this case, the management device 30 commands the output reduction range so that the excess power after the command for all of the multiple facilities 20 is equal to each other at "-0.06 kW", that is, so that the purchased power is equal to 0.06 kW. Specifically, an output reduction range of 0.16 kW is allocated to power supply device A, an output reduction range of 0.26 kW is allocated to power supply device B, an output reduction range of 0.06 kW is allocated to power supply device C, an output reduction range of 0.16 kW is allocated to power supply device D, and an output reduction range of 0.16 kW is allocated to power supply device E.

[Example of determination method 4]
In the judgment method example 4, as shown in Table 6 below, when the management device 30 transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device 30 prioritizes the command of the output reduction width such that the post-command excess power derived by subtracting the load power of the power load device 4 from the post-command output power after the output power of the power supply device is reduced in response to the output control command becomes zero or more in the multiple facilities 20 to which the output control command is transmitted, and the post-command output power becomes the same or close to the value of the other power supplies. For example, in the case of the fuel cell unit 12, the higher the output power is, that is, the closer the output power is to the rated output, the more efficient the operation is, and it can be determined that the monetary loss is unlikely to be large even if the output power is reduced. Also, the higher the output power is, the more likely it is that the facility 20 can reduce the output power of the fuel cell device 10 while avoiding purchasing power from the power grid 1, even if the output power is reduced.

As shown in Table 6, among power supplies A, B, C, D, and E, only power supplies A, B, D, and E have a lowering margin (no power purchase) that changes the output power in a negative direction without generating purchased power. In other words, power supply C does not have a lowering margin (no power purchase), and if the output power is reduced, the excess power after the command cannot be made zero or more, so an output control command to reduce the output power is not sent. As a result, an output reduction width of 0.1 kW is allocated to power supply E, an output reduction width of 0.125 kW is allocated to power supply B, and an output reduction width of 0.075 kW is allocated to power supply A. In this case, looking at the post-command output power of the power supplies after it has been reduced in accordance with the output control command, including power supplies C and D, which are not allocated an output reduction range, the order is power supply C (0.4 kW) and power supply E (0.4 kW) → power supply A (0.325 kW) and power supply B (0.325 kW) → power supply D (0.3 kW), and the post-command excess power is set to be zero or more, and the post-command output power is large and is the same or close to the value of the other power supplies.

Although excess power exists in power supply D, which is not allocated an output reduction width, its original output power is 0.3 kW, which is smaller than the post-command output power of the other power supply devices A, B, and E. Therefore, from the viewpoint of prioritizing the command of an output reduction width such that the post-command output power is the same or close to the value of the other power supply devices, no output reduction width is allocated to power supply device D.

[Example of determination method 5]
As shown in Table 7 below, judgment method example 5 is a case in which, when the management device 30 transmits an output control command to increase the output power of a power supply device during a command transmission process, the management device 30 prioritizes transmitting the output control command to a power supply device installed in a facility 20 that is likely to have greater financial benefit from increasing the output power of the power supply device in accordance with the output control command during the control period, among multiple power supply devices.

In the case of the fuel cell unit 12, the power generation efficiency increases as the output power increases, so it can be said that the smaller the output power, the greater the financial benefit is likely to be when the output power is changed in a positive direction.

In the example shown in Table 7, power supplies A, B, C, D, and E all have a margin of error that changes the output power in a positive direction. If they are arranged in ascending order of output power, i.e., in order of the likelihood of increasing financial profits at facility 20, the order is power supply D → power supplies A and C → power supply B → power supply E. As a result, in order to ensure that the post-command output powers of power supplies A, B, C, D, and E are approximately the same, an output increase of 0.0625 kW is allocated to power supply A, an output increase of 0.0125 kW is allocated to power supply B, an output increase of 0.0625 kW is allocated to power supply C, and an output increase of 0.1625 kW is allocated to power supply D. Specifically, the post-command output powers of power supplies A, B, C, and D are 0.4625 kW, and power supply E is 0.5 kW, so that they are approximately the same.

By increasing the output power of the power supply device, it may be possible to avoid purchasing electricity from the power grid 1 at the facility 20. Therefore, it can be said that the smaller the excess power derived by subtracting the load power of the power load device 4 from the output power of the power supply device at the facility 20, the greater the financial profit at the facility 20 is likely to be.

In the example shown in Table 8, power purchases occur in power supplies C and E. In other words, the excess power of power supplies C and E is small. And, focusing on the purchased power portion, as the increase margin (purchased power portion) that changes the output power in a positive direction, power supply C has an increase margin of 0.1 kW, and power supply E has an increase margin of 0.2 kW. And, if the purchased power is eliminated by increasing the output power by that amount, it can be said that the financial benefit will be large. Therefore, of the required output increase width: 0.4 kW, the output increase width: 0.1 kW is preferentially allocated to power supply C, and the output increase width: 0.2 kW is preferentially allocated to power supply E. In addition, in the example of Table 8, the remaining output increase width: 0.1 kW is evenly allocated to all power supplies A, B, C, D, and E by 0.02 kW each. As a result, a power increase of 0.02 kW is allocated to power supplies A, B, and D, a power increase of 0.12 kW is allocated to power supply C, and a power increase of 0.22 kW is allocated to power supply E.

[Example of determination method 6]
In judgment method example 6, as shown in Table 9 below, when the management device 30 sends an output control command to reduce the output power of a power supply device during the command transmission process, the management device 30 prioritizes sending the output control command to a power supply device installed in a facility 20 that has a small cumulative financial loss caused by command transmission processes performed during a specified period of the past, and when the management device 30 sends an output control command to increase the output power of a power supply device during the command transmission process, the management device 30 prioritizes sending the output control command to a power supply device installed in a facility 20 that has a large cumulative financial loss caused by command transmission processes performed during a specified period of the past.

For example, the cumulative monetary loss at the facility 20 caused by the command transmission process performed during a specified period in the past can be derived from the sum of the cumulative additional operating costs and the cumulative power purchase costs. For example, FIG. 4 shows a curve f(x) capable of identifying the additional operating cost per minute caused by the command transmission process. According to this curve f(x), the additional operating cost is derived to be higher as the post-command output power decreases, based on the fact that the power generation efficiency increases as the output power increases in the case of the fuel cell unit 12. For example, when the post-command output power is 700 W, which is the upper limit output power (i.e., the rated output power) of the fuel cell device 10 as a power supply device, the additional operating cost per minute caused by the command transmission process is derived as 0 yen. In addition, when purchased power is generated by changing the output power in response to a command, the fee for the amount of purchased power is derived as the power purchase cost.

In the example shown in Table 9, the cumulative increase in utility costs (i.e., monetary loss) caused by command transmission processing performed during a specified period in the past is 350 yen for power supply A, 400 yen for power supply B, 450 yen for power supply C, 280 yen for power supply D, and 500 yen for power supply E. Therefore, the power supplies in facility 20 with the largest cumulative monetary losses are, in descending order, power supply E → power supply C → power supply B → power supply A → power supply D. As a result, management device 30 allocates the total output power increase of 0.3 kW to an output increase of 0.2 kW for power supply E and an output increase of 0.1 kW for power supply C.

In the example shown in Table 10, the cumulative increase in utility costs (i.e., monetary loss) caused by command transmission processing performed during a specified period in the past is 350 yen for power supply A, 400 yen for power supply B, 450 yen for power supply C, 280 yen for power supply D, and 500 yen for power supply E. Therefore, the power supplies in facility 20 with the smallest cumulative monetary loss are, in ascending order, power supply D → power supply A → power supply B → power supply C → power supply E. As a result, management device 30 allocates the total output power reduction of 0.3 kW to the output reduction range of 0.1 kW for each of power supplies A, B, and D.

As described above, by performing an allocation such as that of determination method example 6, the cumulative monetary losses of multiple power supply devices are equalized when the multiple power supply devices are operated in response to an output control command to reduce or increase the output power.

<Another embodiment>
＜1＞
In the above embodiment, a specific example of the configuration of the power management system of the present invention has been given and explained, but the configuration can be modified as appropriate.
For example, in the above embodiment, an example has been described in which the power supply unit of the power supply device includes the fuel cell unit 12, but the power supply unit may be another device capable of outputting electric power. For example, the power supply unit may be a device including a charge/discharge unit such as a storage battery. In that case, a charge/discharge device is realized that has the functions of a power supply device used in a power management system and the power supply unit includes a charge/discharge unit.
Alternatively, the power supply unit may be a device including an engine and a generator driven by the engine.

＜2＞
In the above embodiment, specific numerical values for the output power, load power, power receiving point power, length of the control target period, etc. are given as examples and explained, but these numerical values are given for illustrative purposes only and can be changed as appropriate.

＜3＞
The configurations disclosed in the above embodiments (including other embodiments, the same applies below) can be applied in combination with configurations disclosed in other embodiments, provided that no contradiction arises. Furthermore, the embodiments disclosed in this specification are illustrative, and the embodiments of the present invention are not limited thereto, and can be appropriately modified within the scope that does not deviate from the purpose of the present invention.

The present invention can be used in a power management system that issues commands to power supplies while taking into account financial losses at the facility.

1 Power system 2 Power line 3 Power meter 4 Power load device 5 Gateway 6 Router 7 Remote control 8 Power measurement unit 10 Fuel cell device (power supply device)
11 Power conversion unit 12 Fuel cell unit (power supply unit)
13 Fuel cell control unit 14 Memory unit 20 Facility 30 Management device 40 Aggregation coordinator

Claims (11)

A power supply management system including: a power supply device installed in each of a plurality of facilities and capable of outputting electric power; and a management device capable of communicating with the plurality of power supply devices from a remote location outside the facilities,
The power supply device includes a power supply unit connected to a power grid,
a power load device installed in the facility is configured to receive power supply from at least one of the power supply device and the power system installed in the facility;
The management device performs a command transmission process for transmitting output control commands to the plurality of power supply devices to determine output power of the power supply devices;
When the power supply device receives the output control command from the management device, the power supply device operates to supply an output power determined based on the output control command during a control period that is the subject of the output control command;
In the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility that is unlikely to cause a large financial loss when the power supply device operates in accordance with the output control command during the control target period, among the plurality of power supply devices ;
A power supply management system in which, when the management device sends an output control command to reduce the output power of the power supply unit during the command transmission process, the greater the excess power derived by subtracting the load power of the power load device from the output power of the power supply unit in the facility, the less likely the financial loss at the facility is to be large . A power supply management system including: a power supply device installed in each of a plurality of facilities and capable of outputting electric power; and a management device capable of communicating with the plurality of power supply devices from a remote location outside the facilities,
The power supply device includes a power supply unit connected to a power grid,
a power load device installed in the facility is configured to receive power supply from at least one of the power supply device and the power system installed in the facility;
The management device performs a command transmission process for transmitting output control commands to the plurality of power supply devices to determine output power of the power supply devices;
When the power supply device receives the output control command from the management device, the power supply device operates to supply an output power determined based on the output control command during a control period that is the subject of the output control command;
In the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility that is unlikely to cause a large financial loss when the power supply devices operate in accordance with the output control command during the control target period, among the plurality of power supply devices ;
A power management system in which, when the management device sends an output control command to reduce the output power of the power supply unit during the command transmission process, the management device determines that the greater the output power of the power supply unit in the facility, the less likely the financial loss at the facility is to be large . 3. The power supply management system of claim 1 or 2, wherein, when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates an output reduction range to be instructed to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted, the post-command excess power derived by subtracting the load power of the power load device from the post-command output power after the output power of the power supply device is reduced in accordance with the output control command becomes zero or greater, and the post-command output power becomes the same or close to a value of the other power supply devices. 3. The power management system of claim 1 or 2, wherein when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates an output reduction amount to be instructed to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted, the post-command excess power derived by subtracting the load power of the power load device from the post- command output power after the output power of the power supply device is reduced in accordance with the output control command is zero or more. 3. The power supply management system of claim 1 or 2, wherein when the management device transmits an output control command to reduce the output power of the power supply device in the command transmission process, the management device allocates an output reduction range to be instructed to the multiple power supply devices so that, in the multiple facilities to which the output control command is transmitted , the post-command excess power derived by subtracting the load power of the power load device from the post-command output power of the power supply device in the facility after the output power of the power supply device is reduced in accordance with the output control command is equal to or greater than a predetermined value greater than zero . A power management system as described in any one of claims 3 to 5, wherein, in the command transmission process, if the post-command excess power after reducing the output power of the power supply device in accordance with the output control command becomes less than zero in all of the multiple facilities, the management device commands an output reduction amount such that the post-command excess power of all of the multiple facilities becomes equal to each other. When transmitting the output control command to increase the output power of the power supply device in the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility where a financial benefit is likely to be large when the output power of the power supply device is increased in response to the output control command during the control target period , among the plurality of power supply devices;
A power management system as described in any one of claims 1 to 6, wherein, when the management device sends an output control command to increase the output power of the power supply device in the command transmission process, the management device determines that the smaller the excess power derived by subtracting the load power of the power load device from the output power of the power supply device in the facility, the greater the likelihood of the financial benefit in the facility . When transmitting the output control command to increase the output power of the power supply device in the command transmission process, the management device transmits the output control command preferentially to a power supply device provided in the facility where a financial benefit is likely to be large when the output power of the power supply device is increased in response to the output control command during the control target period , among the plurality of power supply devices;
A power management system as described in any one of claims 1 to 6, wherein, in the command transmission process, when the management device sends an output control command to increase the output power of the power supply device, it determines that the smaller the output power of the power supply device in the facility, the greater the likelihood of the financial benefit in the facility . The management device includes:
In the command transmission process, when transmitting the output control command to reduce the output power of the power supply device, the output control command is preferentially transmitted to the power supply device provided in the facility for which the cumulative total of the monetary loss caused by the command transmission process performed during a predetermined period in the past is small;
3. The power management system according to claim 1 or 2, wherein, in the command transmission process, when an output control command is sent to increase the output power of the power supply device, the output control command is preferentially sent to the power supply device installed in the facility that has experienced a large cumulative monetary loss due to the command transmission process performed during the specified period in the past. 10. A fuel cell device comprising the functions of the power supply device used in the power supply management system according to claim 1 , wherein the power supply unit comprises a fuel cell. A charge/discharge device having the functions of the power supply device used in the power supply management system according to any one of claims 1 to 9 , wherein the power supply unit includes a charge/discharge unit.

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