JP7354394B2 - Power management device and power management method - Google Patents

Description

The present invention relates to a power management device and a power management method.

In recent years, power generation devices that utilize natural energies such as solar power, wind power, hydropower, and geothermal energy have been attracting attention. Furthermore, a mechanism is known in which the output power of a power generation device installed in a facility is consumed by the facility (for example, load equipment) (so-called self-consumption). Private power consumption includes power for charging a power storage device installed in a facility (for example, Patent Document 1).

Furthermore, there is also known a technique for determining a charging/discharging schedule for a power storage device based on a predicted value of output power of a power generation device, a predicted value of power consumption of load equipment, and a predicted value of power purchase price (for example, Patent Document 2, 3).

Japanese Patent Application Publication No. 2017-191523 Patent No. 5672186 Patent No. 6386744

By the way, with the end of the fixed purchase price (FIT), the promotion of home consumption is attracting attention. In self-consumption, if there is surplus power that is the difference between the output power of the power generation device and the power consumption of the load equipment, it is preferable to preferentially charge the power storage device using such surplus power.

On the other hand, when there is a shortage of power in the power grid, there may be cases where the balance of supply and demand in the power grid is adjusted (for example, negawatt trading).

However, in such a case, if the power storage device is already fully charged, it is assumed that the power supply and demand balance of the power system cannot be appropriately adjusted due to a decrease in the charging power of the power storage device.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a power management device and a power management method that make it possible to appropriately adjust the power supply and demand balance in the power system. do.

A first feature is that the power management device includes a control section that executes charging control for charging a power storage device using surplus power generated by output power of a power generation device, and the control section includes, in the charging control, The gist of the present invention is to execute a first control that limits charging power of the power storage device using the surplus power to be below a first threshold value that is smaller than the surplus power of the power generation device.

A second feature is a power management method that includes a step of performing charging control to charge a power storage device using surplus power generated by the output power of the power generation device, and in the charging control, the surplus power generated by the power generation device is used to charge the power storage device. and executing a first control for limiting charging power of the power storage device using the surplus power to a value below a first threshold value, which is also smaller.

According to the present invention, it is possible to provide a power management device and a power management method that make it possible to appropriately adjust the power supply and demand balance of a power system.

FIG. 1 is a diagram showing a power management system 100 according to an embodiment. FIG. 2 is a diagram showing a facility 300 according to the embodiment. FIG. 3 is a diagram showing the power management server 200 according to the embodiment. FIG. 4 is a diagram showing the local control device 360 according to the embodiment. FIG. 5 is a diagram for explaining charging control according to the embodiment. FIG. 6 is a diagram for explaining charging control according to the embodiment. FIG. 7 is a diagram for explaining charging control according to the embodiment. FIG. 8 is a diagram for explaining discharge control according to the embodiment. FIG. 9 is a diagram for explaining discharge control according to the embodiment. FIG. 10 is a diagram for explaining display control according to the embodiment. FIG. 11 is a diagram for explaining display control according to the embodiment. FIG. 12 is a diagram illustrating a power management method according to the embodiment. FIG. 13 is a diagram illustrating a power management method according to the embodiment.

Embodiments will be described below with reference to the drawings. In addition, in the description of the following drawings, the same or similar parts are given the same or similar symbols. However, the drawings are schematic.

Embodiments will be described below with reference to the drawings. In addition, in the description of the following drawings, the same or similar parts are given the same or similar symbols. However, the drawings are schematic.

[Embodiment]
(power management system)
A power management system according to an embodiment will be described below.

As shown in FIG. 1, the power management system 100 includes a power management server 200, a facility 300, and a power company 400. In FIG. 1, the facilities 300 are illustrated as facilities 300A to 300C.

Each facility 300 is connected to the power system 110. Hereinafter, the flow of power from the power system 110 to the facility 300 will be referred to as a power flow, and the flow of power from the facility 300 to the power system 110 will be referred to as a reverse power flow.

Power management server 200, facility 300, and power company 400 are connected to network 120. Network 120 may provide a link between these entities. For example, network 120 is the Internet. Network 120 may include a dedicated line such as a VPN (Virtual Private Network).

The power management server 200 is a server managed by a business such as a power generation business, a power transmission/distribution business, a retailer, or a resource aggregator. The resource aggregator may be an electric power company that adjusts the power supply and demand balance of the power system 110 in a VPP (Virtual Power Plant). Adjustment of the power supply and demand balance may include a transaction (hereinafter referred to as a negawatt transaction) in which reduced power of tidal power (also referred to as demand power of the facility 300) supplied from the power system 110 to the facility 300 is exchanged for value. Adjustment of the power supply and demand balance may include a transaction in which increased power of the reverse flow power supplied from the facility 300 to the power system 110 is exchanged for value. In the following, a request for adjusting the power supply and demand balance may be referred to as a power saving request. The resource aggregator may be a power company that provides reverse flow power to a power generation company, a power transmission/distribution company, a retail company, etc. in VPP.

The power management server 200 sends a control message that instructs a local control device 360 provided in the facility 300 to control a distributed power source (for example, a solar battery device 310, a power storage device 320, or a fuel cell device 330) provided in the facility 300. Send. For example, the power management server 200 may transmit a power flow control message (for example, DR; Demand Response) requesting control of power flow power, or may transmit a reverse power flow control message requesting control of reverse power flow power. good. Furthermore, the power management server 200 may transmit a power control message to control the operating state of the distributed power source. The degree of control of the power flow power or the reverse power flow power may be expressed as an absolute value (for example, ○○kW) or as a relative value (for example, ○○%). Alternatively, the degree of control of power flow power or reverse power flow power may be expressed in two or more levels. The degree of control of power flow power or reverse power flow power may be expressed by real time pricing (RTP) determined by the current power supply and demand balance, and time of power tariff (TOU) determined by the past balance of power supply and demand. It may also be represented by (Use).

As shown in FIG. 2, the facility 300 includes a solar cell device 310, a power storage device 320, a fuel cell device 330, a load device 340, a local control device 360, a wattmeter 380, and a wattmeter 390. have

The solar cell device 310 is a distributed power source that generates power according to light such as sunlight. The solar cell device 310 may be an example of a distributed power source that allows reverse power flow. The solar cell device 310 may be an example of a distributed power source to which a fixed purchase price (FIT) can be applied. The solar cell device 310 may be a distributed power source whose fixed purchase price application period has expired. For example, the solar cell device 310 includes a PCS (Power Conditioning System) and a solar panel.

Here, the power output from the solar cell device 310 may vary depending on the amount of light such as sunlight received. Therefore, when considering the power generation efficiency of the solar cell device 310, the power output from the solar cell device 310 is variable power that can vary depending on the amount of light received by the solar panel.

The power storage device 320 is a distributed power source that charges and discharges power. Power storage device 320 may be an example of a distributed power source that does not allow reverse power flow. The power storage device 320 may be an example of a distributed power source to which a fixed purchase price cannot be applied. For example, the power storage device 320 is configured by a PCS and a power storage cell.

The fuel cell device 330 is a distributed power source that generates power using fuel. The fuel cell device 330 may be an example of a distributed power source that does not allow reverse power flow. The fuel cell device 330 may be an example of a distributed power source to which a fixed purchase price is not applied. For example, the fuel cell device 330 is composed of a PCS and a fuel cell.

For example, the fuel cell device 330 may be a solid oxide fuel cell (SOFC), a polymer electrolyte fuel cell (PEFC), or a phosphoric acid fuel cell. It may be a phosphoric acid fuel cell (PAFC) or a molten carbonate fuel cell (MCFC).

In the embodiment, the solar cell device 310, the power storage device 320, and the fuel cell device 330 may be regulated power sources used for VPP. The regulated power source is a power source among the distributed power sources provided in the facility 300 that contributes to VPP.

Load device 340 is a device that consumes power. For example, the load device 340 is an air conditioner, a lighting device, an AV (Audio Visual) device, or the like.

The local control device 360 is a device (EMS; Energy Management System) that manages the power of the facility 300. Local control device 360 may control the operating state of solar cell device 310, may control the operating state of power storage device 320 provided in facility 300, and may control the operating state of fuel cell device 330 provided in facility 300. may be controlled. Details of the local control device 360 will be described later (see FIG. 4).

In embodiments, communication between the power management server 200 and the local controller 360 is performed according to a first protocol. On the other hand, communication between the local control device 360 and the distributed power source (solar battery device 310, power storage device 320, or fuel cell device 330) is performed according to a second protocol different from the first protocol. For example, as the first protocol, a protocol compliant with Open ADR (Automated Demand Response) or a unique dedicated protocol can be used. For example, the second protocol can be a protocol based on ECHONET Lite (registered trademark), SEP (Smart Energy Profile) 2.0, KNX, or an original dedicated protocol. Note that the first protocol and the second protocol only need to be different; for example, even if both are unique dedicated protocols, they may be protocols created according to different rules. However, the first protocol and the second protocol may be protocols created according to the same rules.

The wattmeter 380 is an example of a core wattmeter that measures power flow from the power system 110 to the facility 300 and reverse power flow from the facility 300 to the power system 110. For example, power meter 380 is a smart meter belonging to electric power company 400.

Here, the wattmeter 380 transmits to the local control device 360 a message containing an information element indicating the integrated value of the power flow power or the reverse flow power in the unit time every unit time (for example, 30 minutes). Power meter 380 may transmit messages autonomously or upon request of local controller 360. The wattmeter 380 may transmit to the power management server 200 a message including an information element indicating the forward flow power or the reverse flow power in the unit time for each unit time.

The wattmeter 390 is an example of an individual wattmeter that measures the power of each distributed power source (solar battery device 310, power storage device 320, and fuel cell device 330). The wattmeter 390 may be provided at the output end of the PCS of the distributed power source, and may be considered to be part of the distributed power source. In FIG. 2, a wattmeter 391, a wattmeter 392, and a wattmeter 393 are provided as the wattmeter 390. Power meter 391 measures the output power of solar cell device 310. Power meter 392 measures the discharge power of power storage device 320. Power meter 392 may measure charging power of power storage device 320. The wattmeter 393 measures the individual output power of the fuel cell device 330.

Here, the power meter 390 may transmit a message including an information element indicating the power of the distributed power source to the local control device 360 at intervals shorter than a unit time (for example, one minute). The individual output power of the regulated power source may be expressed by an instantaneous value or by an integrated value. Power meter 390 may transmit messages autonomously or upon request of local controller 360.

Returning to FIG. 1, power company 400 is an entity that provides infrastructure such as power system 110, and is, for example, a power generation company or a power transmission and distribution company. The power company 400 may entrust various tasks to an entity that manages the power management server 200.

(power management server)
A power management server according to an embodiment will be described below. As shown in FIG. 3, the power management server 200 includes a management section 210, a communication section 220, and a control section 230. The power management server 200 may be an example of a VTN (Virtual Top Node).

The management unit 210 is configured with a storage medium such as a nonvolatile memory and/or an HDD, and manages information regarding the facility 300. For example, information regarding the facility 300 includes the type of distributed power source (solar battery device 310, power storage device 320, or fuel cell device 330) installed in the facility 300, the type of distributed power source (solar battery device 310, power storage device 320, or fuel cell device 330) installed in the facility 300, These include the specifications of the fuel cell device 330). The specifications may include the rated power generation power of the solar cell device 310, the rated charging power of the power storage device 320, the rated charging power of the power storage device 320, and the rated output power of the fuel cell device 330. The specifications may include the rated capacity of power storage device 320.

The communication unit 220 is configured by a communication module and communicates with the local control device 360 via the network 120. The communication module may be a wireless communication module that complies with standards such as IEEE802.11a/b/g/n, ZigBee, Wi-SUN, LTE, 5G, etc., or a wired communication module that complies with standards such as IEEE802.3. It may be.

As described above, the communication unit 220 performs communication according to the first protocol. For example, the communication unit 220 transmits a first message to the local controller 360 according to a first protocol. The communication unit 220 receives a first message response from the local controller 360 according to a first protocol.

Control unit 230 may include at least one processor. The at least one processor may be comprised of a single integrated circuit (IC) or a plurality of communicatively connected circuits (such as integrated circuits and/or discrete circuits).

The control unit 230 controls each component provided in the power management server 200. For example, the control unit 230 controls the distributed power source (solar battery device 310, power storage device 320, or fuel cell device 330) provided in the facility 300 to a local control device 360 provided in the facility 300 by transmitting a control message. instruct. As described above, the control message may be a power flow control message, a reverse power flow control message, or a power supply control message.

(local control device)
A local control device according to an embodiment will be described below. As shown in FIG. 4, the local control device 360 includes a first communication section 361, a second communication section 362, and a control section 363. The local control device 360 may be an example of a VEN (Virtual End Node). In embodiments, local controller 360 is an example of a power management device.

The first communication unit 361 is configured by a communication module and communicates with the power management server 200 via the network 120. The communication module may be a wireless communication module that complies with standards such as IEEE802.11a/b/g/n, ZigBee, Wi-SUN, LTE, 5G, etc., or a wired communication module that complies with standards such as IEEE802.3. It may be.

As described above, the first communication unit 361 performs communication according to the first protocol. For example, the first communication unit 361 receives a first message from the power management server 200 according to a first protocol. The first communication unit 361 transmits the first message response to the power management server 200 according to the first protocol.

The second communication unit 362 is configured by a communication module, and communicates with a distributed power source (solar battery device 310, power storage device 320, or fuel cell device 330). The communication module may be a wireless communication module that complies with standards such as IEEE802.11a/b/g/n, ZigBee, Wi-SUN, LTE, 5G, etc., and may comply with standards such as IEEE802.3 or proprietary proprietary protocols. It may be a compliant wired communication module.

As described above, the second communication unit 362 performs communication according to the second protocol. For example, the second communication unit 362 transmits the second message to the distributed power source according to the second protocol. The second communication unit 362 receives the second message response from the distributed power source according to the second protocol.

For example, the second communication unit 362 may receive a message from the power meter 380 that includes an information element that specifies forward power or reverse power. The second communication unit 362 may receive a message including an information element specifying the power of each distributed power source from the power meter 390.

Control unit 363 may include at least one processor. The at least one processor may be comprised of a single integrated circuit (IC) or a plurality of communicatively connected circuits (such as integrated circuits and/or discrete circuits).

The control unit 363 controls each component provided in the local control device 360. Specifically, in order to control the power of the facility 300, the control unit 363 instructs the device to set the operating state of the distributed power source by transmitting the second message and receiving the second message response. In order to manage the power of the facility 300, the control unit 363 may instruct the distributed power sources to report information on the distributed power sources by transmitting the second message and receiving the second message response.

In the embodiment, the control unit 363 constitutes a control unit that executes charging control to charge the power storage device using surplus power generated by the output power of the power generation device. The control unit 363 may perform discharge control of the power storage device.

For example, the power generation device may be a solar cell device 310 that allows reverse power flow. The power storage device may be a power storage device 320 that is charged using surplus power. The surplus power may be the difference between the power generated by the solar cell device 310 and the power consumed by the facility 300. The power consumption of the facility 300 may be the power consumption of the load equipment 340. When the fuel cell device 330 is outputting power, the power consumption of the facility 300 may be the power consumption of the load device 340 minus the output power of the fuel cell device 330. The power consumption of the facility 300 is the power consumption of devices installed in the facility 300 (for example, the solar battery device 310, the power storage device 320, the fuel cell device 330, the load equipment 340, the local control device 360, the wattmeter 380, and the wattmeter 390). It may be the sum of In the embodiment, the power consumption of the facility 300 does not include the charging power of the power storage device 320.

In the following, the surplus power may be used as reverse flow power from facility 300 to power grid 110 or as charging power for power storage device 320.

Note that the power demand of the facility 300 may be synonymous with the power flow from the power system 110 to the facility 300. When the power storage device 320 is being charged, the power demand of the facility 300 may be the sum of the power consumption of the facility 300 and the charging power of the power storage device 320. When the power storage device 320 is being discharged, the power demand of the facility 300 may be the power consumption of the facility 300 minus the discharged power of the power storage device 320.

In the following, charging control is performed during a first predetermined period (e.g., from sunrise to sunset) during which power is output from the solar cell device 310, and during a second predetermined period (e.g., from sunset to sunset) during which power is not output from the solar cell device 310. A case in which discharge control is executed during the period from 2000 to sunrise will be exemplified. Furthermore, the application period of the fixed purchase price for the solar battery device 310 has expired, and a usage scenario (in-house consumption) in which the output power of the solar battery device 310 is actively consumed in the facility 300 will be mainly described.
(charging control)

Charging control of power storage device 320 will be described below. In FIGS. 5 to 7, power during the first predetermined period is illustrated. In FIGS. 5 to 7, power per unit time (for example, 30 minutes) is illustrated. The power per unit time shown in FIGS. 5 to 7 may be a predicted value. The predicted value of power may be calculated by machine learning of the correlation between past power and attributes. The attributes may include time of day, day of the week, season, and weather (solar radiation, temperature, humidity, etc.). Instead of machine learning, deep learning using AI (Artificial Intelligence) may be used.

As shown in FIG. 5, the surplus power (see the bottom row) is the difference between the output power of the solar cell device 310 (see the top row) and the power consumption of the facility 300 (see the middle row). When the power consumption of facility 300 is greater than the output power of solar battery device 310, surplus power is zero and power is supplied from power system 110.

In such a case, since the output power of the solar cell device 310 may fluctuate, it is conceivable to use all of the surplus power to charge the power storage device 320 when promoting self-consumption. Specifically, as shown in FIG. 6, charging control of power storage device 320 is considered to be performed without limiting the charging power of power storage device 320 using surplus power. According to such charging control, charging of power storage device 320 is completed at the earliest possible time (time T1 in FIG. 6). In other words, it is possible to reduce the possibility that the output power of the solar cell device 310 will not be used for self-consumption. Completion of charging of power storage device 320 may mean that the remaining amount of power stored in power storage device 320 increases to an upper limit threshold value. The upper limit threshold may be a threshold at which it is determined that power storage device 320 is fully charged.

However, when the charging control shown in FIG. 6 is executed, power storage device 320 is not charged after time T1, so the power saving request cannot be met due to a decrease in the charging power of power storage device 320.

Therefore, in the embodiment, as shown in FIG. 7, in the charging control, the local control device 360 (control unit 363) controls the charging power of the power storage device 320 using the surplus power to be equal to or less than the first threshold value smaller than the surplus power. Execute the first control to limit. The power obtained by subtracting the charging power of power storage device 320 from the surplus power is reverse flow power to power grid 110. Here, it should be noted that in the first control, since power storage device 320 is charged, the charging power of power storage device 320 is greater than zero.

According to such a configuration, the time when charging of power storage device 320 is completed is time T2, which is later than time T1 shown in FIG. 6. That is, by reducing the charging power of power storage device 320 using surplus power, it is possible to extend the period during which a request for power saving can be met. As described above, the adjustment of the power supply and demand balance may include a request to reduce the power demand of the facility 300 (for example, a negawatt transaction), or may include a request to increase the reverse flow power of the facility 300.

Local control device 360 specifies the total amount of charging power to be charged to power storage device 320 using surplus power during a first predetermined period including the target time when the first control is applied, and ensures that the specified total amount of charging power is secured. The first threshold value may be set so as to

Specifically, the local control device 360 performs the prediction based on the predicted total output power (the integrated value of the output power shown in the upper part of FIG. 5) and the predicted total power consumption (the integrated value of the power consumption shown in the middle part of FIG. 5). The total amount of surplus power (the integrated value of surplus power shown in the lower part of FIG. 5) is specified. Local control device 360 specifies the total amount of charging power (the integrated value of charging power shown in the lower part of FIG. 6 or the lower part of FIG. 7) based on the predicted total amount of surplus power and the storable capacity of power storage device 320. The storable capacity of power storage device 320 is the difference between the rated capacity of power storage device 320 and the remaining power storage amount of power storage device 320 at the start of the first predetermined period. If the predicted total amount of surplus power is larger than the storable capacity of power storage device 320, local control device 360 uses the storable capacity of power storage device 320 as the total amount of charging power. On the other hand, if the predicted total amount of surplus power is smaller than the storage capacity of power storage device 320, local control device 360 uses the predicted total amount of surplus power as the total amount of charging power.

Under such a premise, the local control device 360 sets the first threshold so that the total amount of charging power shown in the lower part of FIG. 7 is equal to the total amount of charging power shown in the lower part of FIG. 6.

According to such a configuration, since the output power of the solar battery device 310 used for self-consumption (that is, the total amount of charging power) does not change during the entire first predetermined period, the self-consumption can be performed without any disadvantage to the user. It can promote consumption.

Here, the target time to which the first control is applied may include one or more unit times. The target time to which the first control is applied may be determined regardless of the unit time. That is, the target time to which the first control is applied may have any length of time.

The local control device 360 may execute the first control even if the selling price of surplus power is lower than the predetermined price at the target time when the first control is applied. The predetermined price may be determined based on the purchase price of power supplied from the power system 110. For example, the predetermined price may be the same as the power purchase price, a price higher than the power purchase price by an offset amount, or a price lower than the power purchase price by an offset amount.

In other words, during the target time when the selling price of surplus electricity is lower than the predetermined price, that is, the target time when self-consumption should normally be prioritized, the period during which it is possible to respond to the power saving request by executing the first control. may be extended.

The rated capacity of power storage device 320 may be smaller than the total amount of output power that is expected to be output from solar cell device 310 in a predetermined expected period including the time that solar cell device 310 is expected to output power. In embodiments, the predetermined expected period may be the same as the first predetermined period. The expected total output power amount may be a static value determined at the stage of installing the solar cell device 310 instead of a dynamic value that may change after the solar cell device 310 is installed. The expected total output power amount may be determined based on the rated output power of the solar cell device 310. The expected total output power amount may be determined based on attributes that affect the output power of the solar cell device 310. The attributes may include the installation location of the solar cell device 310, the estimated amount of solar radiation at the installation location, and the like. Under such conditions, local control device 360 may execute the first control described above in charge control.

The rated capacity of power storage device 320 may be smaller than the estimated total amount of surplus power that is expected to occur during a predetermined expected period that includes the time that surplus power is expected to be generated. In embodiments, the predetermined expected period may be the same as the first predetermined period. The estimated total amount of surplus power may not be a dynamic value that may change after the solar cell device 310 is installed, but may be a static value that is determined at the stage of installing the solar cell device 310. The estimated total amount of surplus power may be determined based on the above-mentioned estimated total output power amount and attributes of the facility 300. The attributes of the facility 300 may include the type of the facility 300 (for example, commercial facility, store, apartment complex, detached house, etc.), the estimated power consumption of the facility 300 during the first predetermined period, and the like. Under such conditions, local control device 360 may execute the first control described above in charge control.

Local control device 360 may perform the first control when the predicted total amount of surplus power that is predicted to occur in the first predetermined period is larger than the rated capacity of power storage device 320. The predicted total amount of surplus power may not be a static value determined at the stage of installing the solar cell device 310, but may be a dynamic value that can change after the solar cell device 310 is installed. The predicted total surplus power is calculated by calculating the difference between the predicted total output power (the integrated value of the output power shown in the upper part of Figure 5) and the predicted total power consumption (the integrated value of the power consumption shown in the middle part of Figure 5) (the lower part of Figure 5). (integrated value of surplus power shown) may be used. In other words, if all of the surplus power cannot be used to charge power storage device 320 during the first predetermined period, local control device 360 may perform the above-described first control in charging control.

Local control device 360 may perform charging control without using power supplied from power system 110. However, if charging of the power storage device 320 is not completed even if all of the surplus power is used to charge the power storage device 320 during the first predetermined period, the local control device 360 uses the power supplied from the power system 110. Charging control may also be executed by

(discharge control)
Discharge control of power storage device 320 will be described below. In FIGS. 8 and 9, power during the second predetermined period is illustrated. In FIGS. 8 and 9, power per unit time (for example, 30 minutes) is illustrated. The power per unit time shown in FIGS. 8 and 9 may be predicted values. The predicted value of power may be calculated by machine learning of the correlation between past power and attributes. Attributes may include time of day, day of the week, and season. Deep learning using AI may be used instead of machine learning.

In such a case, when promoting self-consumption, it is preferable to complete discharging of power storage device 320 by the time the first predetermined period described above starts. Therefore, it is conceivable that all of the power consumption of facility 300 is covered by the discharged power of power storage device 320. Specifically, as shown in FIG. 8, discharge control of power storage device 320 is considered to be executed without limiting the discharge power of power storage device 320. According to such discharge control, the discharge of power storage device 320 is completed at the earliest possible time (time T3 in FIG. 8). In other words, it is possible to reduce the possibility that discharging of power storage device 320 will not be completed during the second predetermined period. Completion of discharging of power storage device 320 may mean that the remaining amount of power stored in power storage device 320 decreases to a lower limit threshold value. The lower limit threshold may be a threshold at which it is determined that power storage device 320 has run out of remaining power. The lower limit threshold may be a threshold at which the remaining power storage amount used in BCP (Business continuity plan) is secured.

However, if the discharge control shown in FIG. 8 is executed, power storage device 320 cannot be discharged after time T3, and therefore the power saving request cannot be met by increasing the discharge power of power storage device 320.

Therefore, in the embodiment, as shown in FIG. 9, local control device 360 (control unit 363) performs second control in discharging control to limit the discharge power of power storage device 320 to a second threshold value or less. Here, in the second control, since power storage device 320 is discharged, it should be noted that the discharge power of power storage device 320 is greater than zero.

According to such a configuration, the time when the discharge of power storage device 320 is completed is time T4, which is later than time T3 shown in FIG. That is, by increasing the discharge power of power storage device 320, it is possible to extend the period during which a request for power saving can be met.

Local control device 360 specifies the total amount of discharged power discharged from power storage device 320 in the second predetermined period based on the remaining amount of power stored in power storage device 320 at the start of the second predetermined period, and determines the total amount of discharged power discharged from power storage device 320 in the second predetermined period. The second threshold value may be set to ensure that.

For example, local control device 360 may use the remaining amount of power stored in power storage device 320 as the total amount of discharged power. In such a case, if the remaining amount of power stored in the power storage device 320 is greater than the total amount of power consumed by the facility 300 during the second predetermined period, and reverse flow of the discharged power of the power storage device 320 is allowed, Local control device 360 may perform a reverse flow of power corresponding to the difference between the remaining amount of power stored in power storage device 320 and the total power consumption.

The local control device 360 may specify the total amount of discharged power based on the predicted total amount of power consumption that is predicted to be consumed in the facility 300 during the second predetermined period. The predicted total power consumption is not a static value that is determined at the stage of installing devices (for example, load equipment 340) installed in facility 300, but changes after the installation of devices (for example, load equipment 340) installed in facility 300. It may be a dynamic value that can be used. For example, the predicted total power consumption is the integrated value of power consumption shown in the upper part of FIG. 8 or the upper part of FIG. 9. For example, when the remaining amount of power stored in power storage device 320 is smaller than the predicted total amount of power consumption, local control device 360 may use the remaining amount of power stored in power storage device 320 as the total amount of discharged power. On the other hand, if the remaining amount of power stored in power storage device 320 is larger than the predicted total power consumption, local control device 360 may use the predicted total power consumption as the total amount of discharged power.

(Display control)
Below, an example of display control of the local control device 360 will be described in charge control including first control and discharging control including second control. Here, display control is control to display predetermined information on a display. Although the display is not particularly limited, the display may be provided in the local control device 360 or may be provided in a user terminal that can communicate with the local control device 360. The user terminal may be a smartphone, a tablet terminal, or a personal computer.

First, an example of display control in charging control including first control will be described. The local control device 360 executes display control to display the image shown in FIG.

As shown in FIG. 10, the local control device 360 may perform display control to notify the user of information indicating that the total amount of charging power is secured and at least one of the effects of the first control. For example, the character string "Charging completion time is scheduled for XX" is an example of information indicating that the total amount of charging power will be secured. The character string "If a power saving request is made, the electricity bill will be reduced by xx yen" is an example of information indicating the effect of the first control.

Local control device 360 may perform display control to notify the user of information indicating that power storage device 320 is being charged using surplus power and reverse flow of surplus power is being performed. For example, “charging power=XXkW” is an example of information indicating that power storage device 320 is being charged using surplus power. "Sold power = xx kW" is an example of information indicating that a reverse flow of surplus power is being performed.

Although the first control is being performed, the local control device 360 may perform display control to notify the user of information indicating that the cost of the facility 300 has been optimized. For example, the character strings ``Charging completion time is scheduled for XX'' and ``If a power saving request is made, the electricity bill will be reduced by XX yen'' indicate that the facility 300 has optimized costs. This is an example of the information shown. The information indicating that the cost of the facility 300 has been optimized is not limited to this, and may be a character string such as "The electricity bill has been optimized."

Second, an example of display control in discharge control including second control will be described. The local control device 360 executes display control to display the image shown in FIG. 11.

As shown in FIG. 11, the local control device 360 may perform display control to notify the user of information indicating at least one of the fact that the total amount of discharge power is secured and the effect of the second control. For example, the character string "Discharge completion time is scheduled for xx" is an example of information indicating that the total amount of discharge power will be secured. The character string "If a power saving request is made, the electricity bill will be reduced by xx yen" is an example of information indicating the effect of the second control.

Local control device 360 may perform display control to notify the user of information indicating that power storage device 320 is being discharged. For example, “discharge power=XXkW” is an example of information indicating that power storage device 320 is being discharged. The local control device 360 may perform display control to notify the user of information indicating that power is being supplied from the power grid 110. For example, "purchased power = xx kW" is an example of information indicating that power is being supplied from the power system 110.

Although the second control is being performed, the local control device 360 may perform display control to notify the user of information indicating that the cost of the facility 300 has been optimized. For example, the character strings ``Discharge completion time is scheduled for XX'' and ``If a power saving request is made, the electricity bill will be reduced by XX yen'' indicate that the facility 300 has optimized its costs. This is an example of the information shown. The information indicating that the cost of the facility 300 has been optimized is not limited to this, and may be a character string such as "The electricity bill has been optimized."

(Power management method)
A power management method according to an embodiment will be described below.

First, charging control including the first control described above will be explained.

As shown in FIG. 12, in step S11, local control device 360 specifies the total amount of charging power. As described above, the total amount of charging power is specified based on the predicted total amount of surplus power and the storable capacity of power storage device 320 at the start of the first predetermined period (see FIGS. 5 and 6).

In step S12, the local control device 360 sets a first threshold value so that the total amount of charging power is ensured during the first predetermined period (see the lower part of FIG. 7).

In step S13, the local control device 360 sets a charging plan including the first control described above (see the lower part of FIG. 7).

In step S14, local control device 360 executes charging control including the first control described above based on the charging plan set in step S13.

In step S15, the local control device 360 executes the display control described above (see FIG. 10).

Second, discharge control including the second control described above will be explained.

As shown in FIG. 13, in step S21, local control device 360 specifies the total discharge power amount. As described above, the total amount of discharged power is specified based on the predicted total amount of power consumption and the remaining amount of power stored in power storage device 320 at the start of the second predetermined period (see FIG. 8).

In step S22, the local control device 360 sets a second threshold value so that the total amount of discharged power is ensured during the second predetermined period (see the lower part of FIG. 9).

In step S23, the local control device 360 sets a discharge plan including the second control described above (see the lower part of FIG. 9).

In step S24, the local control device 360 executes discharge control including the first control described above based on the discharge plan set in step S23.

In step S25, the local control device 360 executes the display control described above (see FIG. 11).

(action and effect)
In the embodiment, in charging control, local control device 360 executes first control that limits charging power of power storage device 320 using surplus power to a value below a first threshold value that is smaller than surplus power. According to such a configuration, it is possible to extend the period during which a request for power saving can be met. As a result, the power supply and demand balance of the power system 110 can be adjusted appropriately.

In the embodiment, the local control device 360 specifies the total amount of charging power to be charged to the power storage device 320 using surplus power in a first predetermined period including the target time to which the first control is applied, and uses the specified charging power. The first threshold value may be set so that the total amount is ensured. According to such a configuration, since the total amount of charging power does not change as a whole during the first predetermined period, self-consumption can be appropriately performed without causing any disadvantage to the user.

In the embodiment, in the discharge control, the local control device 360 may perform second control to limit the discharge power of the power storage device 320 to a second threshold value or less. According to such a configuration, it is possible to extend the period during which a request for power saving can be met. As a result, the power supply and demand balance of the power system 110 can be adjusted appropriately.

In the embodiment, the local control device 360 may specify the total amount of discharged power discharged from the power storage device 320 in the second predetermined period, and may set the second threshold so that the specified total amount of discharged power is ensured. . According to such a configuration, the remaining power storage amount of the power storage device 320 can be appropriately reduced at the start of the first predetermined period, and the possible power storage capacity of the power storage device 320 during the first predetermined period can be secured. . As a result, self-consumption can be appropriately carried out during the first predetermined period.

[Change example 1]
Modification example 1 of the embodiment will be described below. In the following, differences from the embodiment will be mainly explained.

In the embodiment described above, a case has been exemplified in which the local control device 360 executes charging control including specifying the predicted total amount of surplus power, specifying the total amount of charging power, setting the first threshold value, and first control. However, embodiments are not limited thereto.

For example, the total amount of predicted surplus power may be specified by the power management server 200. In such a case, information necessary to identify the predicted total amount of surplus power may be transmitted from the local control device 360 to the power management server 200. Identification of the total amount of charging power may be performed by the power management server 200. In such a case, information necessary to identify the total charging power amount may be transmitted from the local control device 360 to the power management server 200. Setting of the first threshold value may be executed by the power management server 200. In such a case, information necessary for setting the first threshold may be transmitted from the local control device 360 to the power management server 200. Charging control including the first control may be executed by the power management server 200. That is, the charging control including the first control may be executed as part of the VPP control.

In the embodiment described above, a case has been exemplified in which the local control device 360 executes discharge control including specifying the total discharge power amount, setting the second threshold value, and second control. However, embodiments are not limited thereto.

For example, the total discharge power amount may be specified by the power management server 200. In such a case, information necessary for identifying the total amount of discharged power may be transmitted from the local control device 360 to the power management server 200. The setting of the second threshold may be executed by the power management server 200. In such a case, information necessary for setting the second threshold may be transmitted from the local control device 360 to the power management server 200. The discharge control including the second control may be executed by the power management server 200. That is, the discharge control including the second control may be executed as part of the VPP control.

[Other embodiments]
Although the present invention has been described with reference to the embodiments described above, the statements and drawings that form part of this disclosure should not be understood as limiting the present invention. Various alternative embodiments, implementations, and operational techniques will be apparent to those skilled in the art from this disclosure.

In the embodiment, the first predetermined period is a period in one day during which power is output from the solar cell device 310 (for example, from sunrise to sunset). However, embodiments are not limited thereto. The first predetermined period may include at least a portion of the period during which power is output from the solar cell device 310 in one day. The first predetermined period may be any period included in the period during which power is output from the solar cell device 310 in one day. Alternatively, the first predetermined period may be a fixed period such as 6:00 to 18:00 or 10:00 to 14:00. Note that the divisions in one day are not limited to 0:00 to 24:00, and may be arbitrary divisions such as 6:00 to 6:00 the next day.

In the embodiment, the second predetermined period is a period (for example, from sunset to sunrise) during which power is not output from the solar cell device 310 during the day. However, embodiments are not limited thereto. The second predetermined period may include at least a portion of a period during which power is not output from the solar cell device 310 in one day. The second predetermined period may be any period included in the period during which power is not output from the solar cell device 310 in one day. Alternatively, the second predetermined period may be a fixed period such as 18:00 to 6:00 the next day or 22:00 to 2:00 the next day. Note that the divisions in one day are not limited to 0:00 to 24:00, and may be arbitrary divisions such as 6:00 to 6:00 the next day.

In the embodiment, a case is illustrated in which the predetermined expected period is the same as the first predetermined period. However, embodiments are not limited thereto. The predetermined expected period may be different from the first predetermined period. For example, if the first predetermined period is shorter than the period during which power is output from the solar cell device 310, the predetermined expected period may be longer than the first predetermined period. For example, the predetermined expected period may be a period during which power is expected to be output from the solar cell device 310 (for example, a period from sunrise to sunset). Alternatively, the predetermined expected period may be a period during which surplus power is expected to be generated. The predetermined assumed period may be the sum of continuous periods or the sum of discontinuous periods. The predetermined expected period may be considered to be one day.

In the embodiment, the solar cell device 310 is exemplified as a power generation device that allows reverse power flow. However, embodiments are not limited thereto. A power generation device that allows reverse power flow may include a distributed power source that outputs power using renewable energy. Such a distributed power source may include one or more distributed power sources selected from a wind power generation device, a hydroelectric power generation device, a geothermal power generation device, and a biomass power generation device. Note that a reverse flow of the discharged power of the power storage device 320 may be allowed, and a reverse flow of the output power of the fuel cell device 330 may be allowed.

Although not specifically mentioned in the embodiment, the power storage device 320 may include a stationary power storage device, or may include a power storage device mounted on an electric vehicle.

In the embodiment, display control is exemplified as notification control for notifying information to the user. However, embodiments are not limited thereto. The notification control may include audio output control for notifying information by audio.

In the embodiment, a case is illustrated in which the local control device 360 is provided in the facility 300. However, embodiments are not limited thereto. The local control device 360 may be provided by a cloud service implemented by a server provided on the network 120 or the like.

Although not specifically mentioned in the embodiment, the electric power may be an instantaneous value (kW) or an integrated value per unit time (kWh).

DESCRIPTION OF SYMBOLS 100... Power management system, 110... Power system, 120... Network, 200... Power management server, 210... Management department, 220... Communication department, 230... Control department, 300... Facility, 310... Solar battery device, 320... Power storage device , 330... fuel cell device, 340... load equipment, 360... local control device, 361... first communication section, 362... second communication section, 363... control section, 380... wattmeter, 390... wattmeter, wattmeter, 392...wattmeter, 393...wattmeter, 400...power company

Claims (15)

comprising a control unit that executes charging control to charge the power storage device using surplus power generated by the output power of the power generation device,
In the charging control, the control unit executes a first control that limits charging power of the power storage device using the surplus power to a value below a first threshold value that is smaller than the surplus power of the power generation device;
The control unit executes the first control even if the selling price of the surplus electricity is less than the buying price of the electricity supplied from the power system during the target time when the first control is applied,
The control unit is a power management device that reduces charging power of the power storage device using the surplus power in response to a request for reduction of power demand of a facility having the power generation device and the power storage device. The control unit specifies a total amount of charging power to be charged to the power storage device using the surplus power during a first predetermined period including the target time , and controls the first amount of charging power so that the specified total amount of charging power is secured. The power management device according to claim 1, wherein the power management device sets one threshold value. The control unit specifies, during a first predetermined period including the target time, a predicted total surplus power amount based on a predicted output power amount of the power generation device and a predicted total power consumption amount of a facility in which the power storage device is installed, and The total amount of charging power is specified based on the predicted total amount of surplus power and the amount of power that can be stored in the power storage device, and a first threshold is set so that the specified total amount of charging power is secured. Power management device. Claim 2 or claim 2, wherein the rated capacity of the power storage device is smaller than the expected total amount of output power that is expected to be output from the power generation device in a predetermined expected period including the time that is expected to be output from the power generation device. The power management device according to item 3 . According to any one of claims 2 to 4 , the rated capacity of the power storage device is smaller than the estimated total amount of surplus power that is expected to be generated in a predetermined expected period including the time when the surplus power is expected to be generated. The power management device described. Any one of claims 2 to 5 , wherein the control unit executes the first control when a predicted total amount of surplus power that is predicted to occur in the first predetermined period is larger than a rated capacity of the power storage device. The power management device according to item 1. The power management device according to any one of claims 1 to 6 , wherein the control unit executes the charging control without using power supplied from the power system. The control unit executes discharge control of the power storage device during a second predetermined period in which power is not output from the power generation device,
The power management device according to any one of claims 1 to 7 , wherein, in the discharge control, the control unit executes second control to limit the discharge power of the power storage device to a second threshold value or less. The control unit specifies the total amount of discharged power discharged from the power storage device during the second predetermined period based on the remaining amount of power stored in the power storage device at the start of the second predetermined period, and calculates the specified discharged power. The power management device according to claim 8 , wherein the second threshold is set so that a total amount is ensured. The control unit specifies the total amount of discharged power based on a predicted total amount of power consumption that is predicted to be consumed in a facility where the power generation device and the power storage device are installed in the second predetermined period . The power management device described. The control unit executes notification control to notify the user of information indicating at least one of the effect of the first control and the fact that the total amount of charging power is secured . The power management device according to any one of claims 4 to 10 , which refers to claim 2 or 3 . The control unit executes notification control to notify the user of information indicating that the power storage device is being charged using the surplus power and that the surplus power is being reversely flowed. The power management device according to any one of claims 1 to 11 . The control unit executes notification control to notify a user of information indicating that the first control is being performed, but the cost of the facility in which the power generation device and the power storage device are installed is optimized. The power management device according to any one of claims 1 to 12 . Step A of performing charging control to charge the power storage device using surplus power generated by the output power of the power generation device;
In the charging control, a step B of performing a first control to limit the charging power of the power storage device using the surplus power to a value below a first threshold value that is smaller than the surplus power of the power generation device ;
a step C of reducing charging power of the power storage device using the surplus power in response to a request for reduction of power demand of a facility having the power generation device and the power storage device;
The step B includes executing the first control even if the selling price of the surplus electricity is less than the buying price of the electricity supplied from the power system during the target time when the first control is applied. , Power management method. 15. The method according to claim 14, further comprising the step of performing notification control to notify a user of information indicating that charging of the power storage device is being performed using the surplus power and that reverse flow of the surplus power is being performed. Power management methods described.