JP7591963B2 - 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 traditional large-scale power plants, power supply devices such as generators 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. Using the power supply devices and power load devices to increase or decrease the facility's receiving point power can contribute to adjusting 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 consumer facilities. Note that the receiving point power 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 Document 1 (JP Patent Publication 2018-125907A) describes a power management system that includes power supply devices (power resources 101) installed in each of a number of facilities, and a management device (virtual power generation central device 103) that can communicate with the multiple power supply devices. The management device selects the power supply device to be the target of an operation command based on evaluation criteria such as economic efficiency, the impact on consumers of reduced power load, reliability in activating the power supply device, the possibility of failure and extended operating life of the power supply device, the speed at which the power supply device responds to control commands, and the communication performance of the power supply device.

JP 2018-125907 A

Patent document 1 describes a method for selecting a power supply device to be the target of an operation command during a specified control period, but does not describe what operation state the power supply device should be in before being selected. For example, if a power supply device is operating with an output power less than the upper limit output power, i.e., if it is operating in a state with a margin for increasing the output power, it has the margin for decreasing the power at the power receiving point in the facility, so an operation command to increase the output power can be issued to the power supply device during the control period. Also, if a power supply device is operating with an output power greater than the lower limit output power, i.e., if it is operating in a state with a margin for decreasing the output power, it has the margin for increasing the power at the power receiving point in the facility, so an operation command to decrease the output power can be issued to the power supply device during the control period.

The present invention has been made in consideration of the above problems, and its purpose is to provide a power management system that can provide both an adjustment capability to increase the receiving point power and an adjustment capability to decrease the receiving point power, and a fuel cell device and a charge/discharge device as power supply devices 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 that is connected to a power grid and is configured to adjust an output power between an upper limit output power and a lower limit output power;
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 can transmit, to a plurality of the power supply devices, output control commands that 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 in a first operation mode that aims to supply output power determined based on the output control command during a control period that is the subject of the output control command, and operates in a second operation mode different from the first operation mode during a non-control period that is outside the control period;
The multiple power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is limited to a value less than the upper limit output power, and a device in which the second operating mode is set to an operating mode in which the output power is limited to a value exceeding the lower limit output power.

According to the above characteristic configuration, a power supply device whose output power is limited to a value less than the upper limit output power has a margin for increasing the output power of the power supply device, i.e., a margin for decreasing the power receiving point power in the facility. In other words, a facility in which a power supply device whose second operation mode is set to an operation mode in which the output power is limited to a value less than the upper limit output power is provided is prepared to respond to an output control command for decreasing the power receiving point power in the facility during the control period before the start of the control period. Also, a power supply device whose output power is limited to a value exceeding the lower limit output power has a margin for decreasing the output power of the power supply device, i.e., a margin for increasing the power receiving point power in the facility. In other words, a facility in which a power supply device whose second operation mode is set to an operation mode in which the output power is limited to a value exceeding the lower limit output power is provided is prepared to respond to an output control command for increasing the power receiving point power in the facility during the control period before the start of the control period. In this way, the power management system with this characteristic configuration can provide both adjustment power to increase the power receiving point and adjustment power to decrease the power receiving point during the control period using one of multiple power supply devices.

Another characteristic feature of the power management system according to the present invention is that the multiple power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to a value less than the upper limit output power and closest to the load power of the power load device, and a device in which the second operating mode is set to an operating mode in which the output power is set to the upper limit output power.

According to the above characteristic configuration, when the second operation mode is an operation mode in which the output power is set to a value less than the upper limit output power and closest to the load power of the power load device, it is possible to ensure a margin for increasing the output power of the power supply device during the controlled period while reducing the amount of power purchased from the power grid in the facility during the non-control period. Also, when the second operation mode is set to an operation mode in which the output power is set to the upper limit output power, it is possible to ensure a margin for decreasing the output power of the power supply device during the controlled period while reducing the amount of power purchased from the power grid in the facility during the non-control period.

Another characteristic feature of the power management system according to the present invention is that the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to a constant value that is less than the upper limit output power and exceeds the lower limit output power.

According to the above characteristic configuration, when the second operating mode is set to an operating mode in which the output power is set to a constant value that is less than the upper limit output power and exceeds the lower limit output power, it is possible to secure both the capacity to increase the output power of the power supply device and the capacity to decrease the output power of the power supply device during the control target period.

Another characteristic configuration of the power management system of the present invention is that the multiple power supply devices are configured to include a device whose second operating mode is set to an operating mode in which the output power is less than the upper limit output power and is closest to a value that is a predetermined value greater than the load power of the power load device.
In this case, in the power supply device, the predetermined value may be set to a value that satisfies the condition: (the upper limit output power-the load power) x 0.5.

The above characteristic configuration makes it possible to reduce the amount of power purchased from the power grid at the facility during non-control periods, while ensuring a margin for both increasing the output power of the power supply device and decreasing the output power of the power supply device during control periods.

Another characteristic feature of the power management system according to the present invention is that the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to the greater of a constant value that is less than the upper output power limit and exceeds the lower output power limit, and the load power of the power load device.

The above characteristic configuration allows the facility to reduce the amount of electricity purchased from the power grid during non-control periods.

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 can provide both an adjustment capability to increase the power at the receiving point and an adjustment capability to decrease the power at the receiving point.

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 management system that can provide both an adjustment capability to increase the power at the receiving point and an adjustment capability to decrease the power at the receiving point.

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.

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 the output power of the fuel cell device 10 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 the output power of the fuel cell device 10 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 8 (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 can transmit output control commands that determine the output power of the fuel cell devices 10 to 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.

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.

The multiple fuel cell devices 10 that communicate with the management device 30 are configured to include devices in which the second operating mode is set to an operating mode in which the output power is limited to a value less than the upper limit output power, and devices in which the second operating mode is set to an operating mode in which the output power is limited to a value greater than the lower limit output power.

The fuel cell device 10, whose output power is limited to a value less than the upper limit output power, has the capacity to increase the output power of the fuel cell device 10, i.e., the capacity to reduce the power receiving point power at the facility 20. In other words, the facility 20 in which the fuel cell device 10, whose second operating mode is set to an operating mode in which the output power is limited to a value less than the upper limit output power, is said to be ready to comply with an output control command to reduce the power receiving point power at the facility 20 during the control period, at a point before the start of the control period.

The fuel cell device 10, whose output power is limited to a value exceeding the lower limit output power, has the capacity to reduce the output power of the fuel cell device 10, i.e., the capacity to increase the power receiving point power at the facility 20. In other words, the facility 20 in which the fuel cell device 10, whose second operating mode is set to an operating mode in which the output power is limited to a value exceeding the lower limit output power, is prepared to respond to an output control command to increase the power receiving point power at the facility 20 during the control period, at a point before the start of the control period.

In this way, by including among the multiple fuel cell devices 10 that communicate with the management device 30 a device in which the second operating mode is set to an operating mode in which the output power is limited to a value below the upper limit output power, and a device in which the second operating mode is set to an operating mode in which the output power is limited to a value above the lower limit output power, it is possible to provide both an adjustment power to increase the receiving point power and an adjustment power to decrease the receiving point power by using any of the multiple fuel cell devices 10 during the control target period.

A specific example of the second operating mode will be described below. In the following description, it is assumed that a power supply device such as a fuel cell device 10 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). In addition, it is assumed that one management device 30 transmits output control commands to five power supply devices A, B, C, D, and E.

[Example 1 of the second operation mode]
Specific example 1 is a case in which a plurality of power supply devices are configured to include devices (power supply devices C, D, E) in which the second operating mode is set to an operating mode in which the output power is less than the upper limit output power and is closest to the load power of the power load device 4, and devices (power supply devices A and B) in which the second operating mode is set to an operating mode in which the output power is set to the upper limit output power, as shown in Table 1 below.

When the operating mode is set so that the output power is less than the upper limit output power and is closest to the load power of the power load device 4 (i.e., power supplies C, D, E), it is possible to ensure a margin for increasing the output power (margin for increasing) during the controlled period while reducing the amount of power purchased from the power grid 1 during the non-control period. Also, when the operating mode is set so that the output power is set to the upper limit output power (i.e., power supplies A, B), it is possible to ensure a margin for decreasing the output power (margin for decreasing) during the controlled period while reducing the amount of power purchased from the power grid 1 during the non-control period.

[Specific example 2 of the second operation mode]
Specific example 2 is a case where the multiple power supply devices are configured to include devices (power supply devices A, B, C, D, and E) whose second operation mode is set to an operation mode in which the output power is set to a constant value that is less than the upper limit output power and exceeds the lower limit output power, as shown in the following Table 2. In the example shown in Table 2, the constant value is set to 0.5 kW.

In this case, the output power of each of the power supply devices A, B, C, D, and E can be increased and decreased during the control period.

[Example 3 of the second operation mode]
As shown in Table 3 below, specific example 3 is a case where the multiple power supply devices are configured to include a device in which the second operation mode is set to an operation mode in which the output power is less than the upper limit output power and is closest to a value that is a predetermined value greater than the load power of the power load device 4. For example, the predetermined value is set to a value that satisfies the condition "(upper limit output power-load power) x 0.5".

In this case, the facility 20 can reduce the amount of power purchased from the power grid 1 during the non-control period, while ensuring a margin for both increasing the output power of the power supply device and decreasing the output power of the power supply device during the control period.

[Example 4 of the second operation mode]
Concrete example 4 is a case where, as shown in the following Table 4, the multiple power supply devices are configured to include a device in which the second operation mode is set to an operation mode in which the output power is set to the larger of a constant value that is less than the upper limit output power and exceeds the lower limit output power, and the load power of the power load device 4. For example, in the example shown in Table 4, 0.5 kW is set as the constant value that is less than the upper limit output power and exceeds the lower limit output power.

In the case shown in Table 4 below, the output power in the second operation mode of the power supply devices A, B, C, D, and E is set as follows.
Power supply device A: Since the load power is 0.3 kW < constant value 0.5 kW, the output power is set to 0.5 kW.
Power supply device B: Since "load power 0.6 kW > constant value 0.5 kW", the output power is set to 0.6 kW.
Power supply device C: Since the load power is 0.4 kW < constant value 0.5 kW, the output power is set to 0.5 kW.
Power supply device D: Since the load power is 0.15 kW < constant value 0.5 kW, the output power is set to 0.5 kW.
Power supply device E: Since the load power is 0.35 kW < constant value 0.5 kW, the output power is set to 0.5 kW.

In this case, the amount of electricity purchased from the power grid 1 at the facility 20 can be reduced during the non-control period.

<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 can provide both adjustment power to increase the receiving point power and adjustment power to decrease the receiving point power.

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 (8)

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 that is connected to a power grid and is configured to adjust an output power between an upper limit output power and a lower limit output power;
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 can transmit, to a plurality of the power supply devices, output control commands that 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 in a first operation mode that aims to supply output power determined based on the output control command during a control period that is the subject of the output control command, and operates in a second operation mode different from the first operation mode during a non-control period that is outside the control period;
A power management system configured so that the multiple power supply devices include a device in which the second operating mode is set to an operating mode in which the output power is limited to a value less than the upper limit output power, and a device in which the second operating mode is set to an operating mode in which the output power is limited to a value greater than the lower limit output power. The power management system according to claim 1, wherein the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to a value less than the upper limit output power and closest to the load power of the power load device, and a device in which the second operating mode is set to an operating mode in which the output power is set to the upper limit output power. The power management system according to claim 1, wherein the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to a constant value that is less than the upper limit output power and exceeds the lower limit output power. The power management system according to claim 1, wherein the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to a value that is less than the upper limit output power and is closest to a value that is a predetermined value greater than the load power of the power load device. The power management system according to claim 4, wherein in the power supply device, the predetermined value is set to a value that satisfies the condition (the upper limit output power - the load power) x 0.5. The power management system according to claim 1, wherein the plurality of power supply devices are configured to include a device in which the second operating mode is set to an operating mode in which the output power is set to the greater of a constant value that is less than the upper limit output power and exceeds the lower limit output power, and the load power of the power load device. A fuel cell device having the functions of the power supply device used in the power supply management system according to any one of claims 1 to 6, the power supply unit being equipped with 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 6, the power supply unit being equipped with a charge/discharge unit.

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