Power management device and power management method

Abstract

To provide a power management device and a power management method allowing appropriate use of a distributed power supply when considering both first control and second control.SOLUTION: A power management device comprises: a management unit that manages distributed power supplies provided respectively in two or more facilities connected with a power system; and a control unit that, in first control for maintaining the frequency of the power system, specifies a target distributed power supply used for the first control. The control unit determines the order of priority of the distributed power supplies specified as the target distributed power supply based on at least one of first priority of the distributed power supply related to the first control and second priority of the distributed power supply related to second control other than the first control.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a power management apparatus and a power management method. [Background technology]

[0002] In recent years, technologies that use power storage devices as distributed power sources (e.g., VPP (Virtual Power Plant)) have become known to maintain the balance between power supply and demand in a power grid. In such cases, it is necessary to adjust the frequency of the power grid by using reverse flow power supplied from the facility to the power grid (hereinafter, "supply and demand adjustment").

[0003] When performing such supply and demand adjustment, a technique is known in which the charge and discharge power of a power storage device is determined for each service (energy management, supply and demand adjustment). For example, in supply and demand adjustment, an upper limit value is set for the charge and discharge power of a power storage device (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-137368 A Summary of the Invention [Problem to be solved by the invention]

[0005] In supply and demand adjustment, available power that can be supplied by a distributed power source such as a power storage device must be submitted in advance to a power management device (e.g., a Resource Aggregator (RA)), and the distributed power source must operate while securing the available power.

[0006] However, even during periods when supply and demand adjustment (hereinafter referred to as the first control) is not necessary, it is necessary for the distributed power source to secure the power it can supply, and for purposes other than the first control, it is only possible to use the remaining power obtained by subtracting the power it can supply from the rated power of the distributed power source. On the other hand, it is also expected that the distributed power source will also be used for control related to the management of facility power demand (hereinafter referred to as the second control).

[0007] Therefore, when considering both the first control and the second control, it is necessary to assume a situation in which the distributed power source cannot be appropriately utilized.

[0008] Therefore, the present invention has been made to solve the above-mentioned problems, and aims to provide a power management device and a power management method that enable appropriate utilization of distributed power sources when taking into account both the first control and the second control. [Means for solving the problem]

[0009] One aspect of the disclosure is a power management device that includes a management unit that manages distributed power sources installed in each of two or more facilities connected to a power system, and a control unit that identifies a target distributed power source to be used in a first control for maintaining the frequency of the power system, wherein the control unit determines a priority order of the distributed power source identified as the target distributed power source based on at least one of a first priority order of the distributed power source for the first control and a second priority order of the distributed power source for a second control other than the first control.

[0010] One aspect of the disclosure is a power management method comprising: a step A of managing distributed power sources installed in each of two or more facilities connected to a power grid; and a step B of identifying a target distributed power source to be used in a first control for maintaining a frequency of the power grid, wherein the step B includes a step of determining a priority order of the distributed power source identified as the target distributed power source based on at least one of a first priority order of the distributed power source for the first control and a second priority order of the distributed power source for a second control other than the first control. Effect of the Invention

[0011] 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 utilize a distributed power source when both the first control and the second control are taken into consideration. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram showing a power management system 1 according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing a facility 100 according to the embodiment. [Diagram 3] FIG. 3 is a diagram showing a power storage device 120 according to an embodiment. [Figure 4] FIG. 4 is a diagram showing a power management server 200 according to the embodiment. [Diagram 5] FIG. 5 is a diagram for explaining frequency fluctuation adjustment according to the embodiment. [Figure 6] FIG. 6 is a diagram for explaining the priority order of the distributed power sources according to the embodiment. [Figure 7] FIG. 7 is a diagram for explaining the priority order of the distributed power sources according to the embodiment. [Figure 8] FIG. 8 is a diagram for explaining the priority order of the distributed power sources according to the embodiment. [Figure 9] FIG. 9 is a diagram for explaining the priority order of the distributed power sources according to the embodiment. [Figure 10] FIG. 10 is a diagram for explaining the priority order of the distributed power sources according to the embodiment. [Figure 11] FIG. 11 is a diagram illustrating a power management method according to an embodiment. [Figure 12] FIG. 12 is a diagram for explaining the priority order of the distributed power sources according to the first modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, the embodiments will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, the drawings are schematic.

[0014] [Embodiment] (Power Management System) A power management system according to an embodiment will be described below. The power management system may be simply referred to as a power system.

[0015] As shown in FIG. 1, the power management system 1 includes a facility 100 and a power management server 200.

[0016] Here, the facility 100 and the power management server 200 are configured to be able to communicate with each other via a network 11. The network 11 may include the Internet, a dedicated line such as a Virtual Private Network (VPN), or a mobile communication network.

[0017] The facility 100 is connected to the power system 12, and may receive power from the power system 12, or may supply power to the power system 12. Power from the power system 12 to the facility 100 may be referred to as forward flow power, purchased power, or demanded power. Power from the facility 100 to the power system 12 may be referred to as reverse flow power or sold power. In FIG. 1, facilities 100A to 100C are illustrated as examples of the facility 100.

[0018] Although not particularly limited, the facility 100 may be a facility such as a residence, a facility such as a store, or a facility such as an office. The facility 100 may be an apartment building including two or more residences. The facility 100 may be a complex including at least two or more of the following facilities: a residence, a store, and an office. Details of the facility 100 will be described later (see FIG. 2).

[0019] The power management server 200 is managed by a business operator who manages power related to the power system 12. The business operator may be a power generation business operator, a power transmission and distribution business operator, or a retail business operator. The business operator may be a resource aggregator (hereinafter, RA), or an aggregation coordinator (AC) that manages the RA. The RA may be a business operator who adjusts the power supply and demand balance of the power system 12. The adjustment of the power supply and demand balance may include a transaction (hereinafter, negawatt trading) in which reduced power of the demand power (flow power) of the facility 100 is exchanged for value. The adjustment of the power supply and demand balance may include a transaction in which increased power of reverse flow power is exchanged for value. In the VPP, the RA may be a business operator such as a power generation business operator, a power transmission and distribution business operator, or a retail business operator.

[0020] In the embodiment, communication between the power management server 200 and the EMS 160 is performed according to a first protocol. On the other hand, communication between the EMS 160 and the distributed power source (the solar cell device 110, the power storage device 120, or the fuel cell device 130) is performed according to a second protocol different from the first protocol. For example, the first protocol may be a protocol conforming to Open ADR (Automated Demand Response) or a unique dedicated protocol. For example, the second protocol may be a protocol conforming to ECHONET Lite (registered trademark), SEP (Smart Energy Profile) 2.0, KNX, or a unique dedicated protocol. Note that the first protocol and the second protocol may be different from each other, and may be, for example, both of which may be unique dedicated protocols, provided that they are protocols created according to different rules. However, the first protocol and the second protocol may be protocols created according to the same rules.

[0021] (facility) A facility according to an embodiment will be described below. As shown in Fig. 2, the facility 100 includes a solar cell device 110, a power storage device 120, a fuel cell device 130, a load device 140, and an EMS (Energy Management System) 160. The facility 100 may also include a measuring device 190.

[0022] The solar cell device 110 is a distributed power source that generates power in response to light such as sunlight. For example, the solar cell device 110 is configured with a PCS (Power Conditioning System) and a solar panel. Here, installation may mean that the solar cell device 110 and the power grid 12 are connected.

[0023] The power storage device 120 is a distributed power source that charges and discharges power. For example, the power storage device 120 is configured with a PCS and a power storage cell. Here, the term "installed" may mean that the power storage device 120 and the power grid 12 are connected to each other.

[0024] The fuel cell device 130 is a distributed power source that generates power using fuel. For example, the fuel cell device 130 is composed of a PCS and a fuel cell. Here, "installation" may mean that the fuel cell device 130 and the power system 12 are connected.

[0025] For example, the fuel cell device 130 may be a solid oxide fuel cell (SOFC; Solid Oxide Fuel Cell), a polymer electrolyte fuel cell (PEFC; Polymer Electrolyte Fuel Cell), a phosphoric acid fuel cell (PAFC; Phosphoric Acid Fuel Cell), or a molten carbonate fuel cell (MCFC; Molten Carbonate Fuel Cell).

[0026] The load device 140 is a device that consumes power. For example, the load device 140 may include an air conditioner that adjusts the temperature of a predetermined space in the facility 100, or may include a lighting device that adjusts the illuminance of a predetermined space in the facility 100. The load device 140 may include a video device, an audio device, a refrigerator, a washing machine, a personal computer, and the like.

[0027] The EMS 160 manages the power related to the facility 100. The EMS 160 may control the solar cell device 110, the power storage device 120, the fuel cell device 130, and the load devices 140. In the embodiment, the EMS 160 is illustrated as an apparatus that receives a control command from the power management server 200, but such an apparatus may be referred to as a gateway or simply as a control unit. The EMS 160 may be referred to as a Local EMS (LEMS), a Home EMS (HEMS), or a VPP controller to distinguish it from the power management server 200.

[0028] The measuring device 190 measures forward flow power from the power system 12 to the facility 100. The measuring device 190 may measure reverse flow power from the facility 100 to the power system 12. For example, the measuring device 190 may be a smart meter belonging to a power company. The measuring device 190 may transmit an information element indicating a measurement result (an integrated value of forward flow power or reverse flow power) in a first interval (e.g., 30 minutes) to the EMS 160 at the first interval. The measuring device 190 may transmit an information element indicating a measurement result in a second interval (e.g., 1 minute) shorter than the first interval to the EMS 160.

[0029] (Electricity storage device) The power storage device according to the embodiment will be described below. As shown in Fig. 3, the power storage device 120 includes a BT 121, a monitoring unit 122, and a control unit 123. Although omitted in Fig. 3, the power storage device 120 may include a PCS. BT121 is a storage cell included in the power storage device 120.

[0030] The monitoring unit 122 monitors the frequency of the power grid 12. For example, the monitoring unit 122 is connected to a measuring device installed between the power grid 12 and the facility 100, and monitors the frequency of the power measured by the measuring device. The measuring device may be installed in a position similar to that of the measuring device 190 described above.

[0031] The control unit 123 may include at least one processor. The at least one processor may be configured by a single integrated circuit (IC), or may be configured by a plurality of circuits (such as integrated circuits and / or discrete circuits) communicatively connected to each other.

[0032] The control unit 123 controls the BT 121. In the embodiment, the control unit 123 may control charging or discharging of the power storage device 120 in a first control for maintaining the frequency of the power grid 12. The control unit 123 may control charging or discharging of the power storage device 120 in a second control other than the first control.

[0033] Here, the first control may be control that autonomously executes charging and discharging based on the frequency of the power grid 12 monitored by the monitoring unit 122. The first control may be applied to short-cycle control (e.g., GF) described later. The first control may be referred to as VPP control.

[0034] The second control may be control related to management of power demand of the facility 100 in which the power storage device 120 is installed. The second control may be control for reducing an error of the power demand of the facility 100 with respect to a planned value. The second control may be referred to as energy management control.

[0035] Although not particularly limited, the error with respect to the planned value of the power demand may be an error between the planned value of the power demand and the actual value of the power demand, or an error between the planned value of the power demand and the predicted value of the power demand. The predicted value of the power demand may be a value predicted at a timing later than the timing when the planned value of the power demand is formulated.

[0036] For example, a period during which the first control may be applied may be defined as a target period (e.g., one day). In such a case, the planned value of the power demand may include a plan formulated at a timing prior to the target period (e.g., 12:00 on the day before the target period). The predicted value of the power demand may include a value predicted at a timing prior to a unit period (e.g., a 30-minute period) included in the target period (e.g., one hour before the unit period).

[0037] (Power Management Server) The power management server according to the embodiment will be described below. As shown in FIG.

[0038] The communication unit 210 is configured by a communication module. The communication module may be a wireless communication module conforming to standards such as IEEE802.11a / b / g / n / ac / ax, ZigBee, Wi-SUN, LTE, 5G, and 6G, or may be a wired communication module conforming to standards such as IEEE802.3.

[0039] For example, the communication unit 210 may communicate with the facility 100 (the power storage device 120 or the EMS 160).

[0040] First, the communication unit 210 may receive information indicating a behavior of the facility 100 regarding the first control (hereinafter, first behavior information) from the facility 100. The first behavior information may include information indicating whether or not participation in the first control is desired, and may include information indicating whether or not active contribution to the first control is desired.

[0041] Secondly, the communication unit 210 may receive information indicating the behavior of the facility 100 regarding the second control (hereinafter, second behavior information) from the facility 100. The second behavior information may include information indicating whether or not to execute the second control while securing the amount of supply that the power storage device 120 can supply for the first control, may include information indicating whether or not to execute the second control as determined by the planned value of the power demand of the facility 100, and may include information indicating whether or not to execute the second control so as to reduce an error with respect to the planned value of the power demand of the facility 100.

[0042] The management unit 220 is configured with a storage medium such as a hard disk drive (HDD), a solid state drive (SSD), or a non-volatile memory.

[0043] The management unit 220 manages information related to the facility 100. For example, the information related to the facility 100 includes the type of distributed power source (solar cell device 110, power storage device 120, or fuel cell device 130) provided in the facility 100, the specifications of the distributed power source (solar cell device 110, power storage device 120, or fuel cell device 130) provided in the facility 100, etc. The specifications may include the rated power generation of the solar cell device 110, the rated charging power of the power storage device 120, the rated charging power of the power storage device 120, and the rated output power of the fuel cell device 130. The specifications may include the rated capacity of the power storage device 120, the maximum charging and discharging power, etc.

[0044] In the embodiment, the management unit 220 constitutes a management unit that manages distributed power sources installed in each of two or more facilities 100 connected to the power grid 12 .

[0045] The control unit 230 may include at least one processor. The at least one processor may be configured by a single integrated circuit (IC), or may be configured by a plurality of circuits (such as integrated circuits and / or discrete circuits) communicatively connected to each other.

[0046] In the embodiment, the control unit 230 is configured as a control unit that identifies a target distributed power source to be used in a first control for maintaining the frequency of the power grid 12. The control unit 230 determines the priority order of the distributed power source identified as the target distributed power source based on at least one of a first priority order of the distributed power source for the first control and a second priority order of the distributed power source for a second control other than the first control. The priority order of the distributed power sources will be described in detail later.

[0047] (Frequency fluctuation adjustment) The following describes the adjustment of the fluctuation in frequency of the power system 12 according to the embodiment.

[0048] As shown in Fig. 5, the control related to the frequency fluctuation adjustment differs for each fluctuation period to be adjusted. Specifically, the control related to the frequency fluctuation adjustment includes short-period control in which the fluctuation period to be adjusted is a short period (e.g., about several tens of seconds to several minutes), medium-period control in which the fluctuation period to be adjusted is a medium period longer than the short period (e.g., about several minutes to several tens of minutes), and long-period control in which the fluctuation period to be adjusted is a long period longer than the medium period (e.g., about several tens of minutes to several hours).

[0049] Here, the short-cycle control may be called GF (Governor Free). The short-cycle control is a control for eliminating supply and demand fluctuations that cannot be followed by the medium-cycle control. For example, such supply and demand fluctuations may cause the operation of an adjustable power source that operates under short-cycle control to stop.

[0050] The medium-term control may be called Load Frequency Control (LFC) or Automatic Frequency Control (AFC). The medium-term control is a control for eliminating supply and demand fluctuations that are difficult to predict.

[0051] The long-cycle control may be called DPC (Dispatching Power Control) or EDC (Economic Load Dispatching Control). The long-cycle control is a control for eliminating supply and demand fluctuations based on supply and demand prediction.

[0052] Although not particularly limited, the specific control in which the power storage device 120 autonomously controls charging and discharging based on the frequency of the power grid 12 may be applied to the short-period control (for example, GF) described above.

[0053] (assignment) In the above-described background, a case in which both the first control and the second control are taken into consideration will be considered. In the following, a case in which the distributed power source used in the first control and the second control is the power storage device 120 will be mainly described. Therefore, the target distributed power source may be referred to as the target power storage device 120.

[0054] In such a case, if it is assumed that the power storage devices 120 that wish to participate in the first control uniformly execute the first control, the following problem occurs.

[0055] First, the power storage device 120 needs to always secure the supplyable amount in order to respond to the first control. Therefore, in reality, it is necessary to secure the supplyable amount even during the period when the first control is not required, and in the second control, the remaining power obtained by subtracting the supplyable power from the rated power of the power storage device 120 can only be used. For example, in the actual situation where the frequency fluctuation is within ±0.2 Hz in 99% or more of the target period in which the first control can be applied, and assuming a case where the adjustment rate is 5%, only about 8% of the supplyable amount is used in the first control. In other words, even though there is a room to use the supplyable amount in the second control, the supplyable amount is always secured, so the power storage device 120 cannot be used effectively.

[0056] Secondly, a method can be considered in which the power management server 200 dynamically controls the power storage device 120 to efficiently execute the first control and the second control, but the first control requires measuring the charge / discharge power of the power storage device 120 at a granularity of 0.3% of the available supply amount, and therefore the load on the power management server 200 to acquire the charge / discharge power of the power storage device 120 at a granularity of 0.3% is extremely large. Therefore, it is better to select the target power storage device 120 in advance and leave the operation of the first control itself to the autonomous operation of the target power storage device 120.

[0057] In the embodiment, in order to solve the above-mentioned problem, the power management server 200 specifies in advance a target power storage device 120 to be used in the first control from among the power storage devices 120 installed in each of two or more facilities 100.

[0058] (Distributed power source priority) The following describes the priority order of the power storage device 120 according to the embodiment. Since the target power storage device 120 is specified by the power management server 200, the operation of the control unit 230 of the power management server 200 will be mainly described.

[0059] First, the control unit 230 may specify a first priority of the power storage device 120 based on the above-mentioned first behavior information.

[0060] The first priority may be defined by a factor indicating whether or not a contribution to the first control is actively desired. For example, the first priority of a power storage device 120 that actively desires to contribute to the first control may be higher than the first priority of a power storage device 120 that does not actively desire to contribute to the first control (hereinafter, judgment criterion 1-A).

[0061] Secondly, the control unit 230 may specify a second priority of the power storage device 120 based on the above-mentioned second behavior information.

[0062] The second priority may be defined by an element indicating whether or not the second control is executed while securing an available supply amount (i.e., an available charge / discharge amount) that the power storage device 120 can supply for the first control. The second priority of the power storage device 120 that executes the second control while securing an available supply amount for the first control may be higher than the second priority of the power storage device 120 that executes the second control without securing an available supply amount for the first control (hereinafter, judgment criterion 2-A).

[0063] The second priority may be defined by an element indicating whether or not to execute the second control as determined by the planned value of the power demand of the facility 100. The second priority of the power storage device 120 that executes the second control as determined by the planned value of the power demand of the facility 100 may be higher than the second priority of the power storage device 120 that does not execute the second control as determined by the planned value of the power demand of the facility 100 (hereinafter, judgment criterion 2-B).

[0064] The second priority may be defined by an element indicating whether or not to execute the second control so as to reduce an error from the planned value of the power demand of the facility 100. The second priority of the power storage device 120 that does not execute the second control so as to reduce an error from the planned value of the power demand of the facility 100 may be higher than the second priority of the power storage device 120 that executes the second control so as to reduce an error from the planned value of the power demand of the facility 100 (hereinafter, judgment criterion 2-C).

[0065] Furthermore, the second priority may be defined by a combination of the above-mentioned criteria 2A to 2C. For example, the second priority of the power storage device 120 that executes the second control as determined by the planned value of the power demand of the facility 100 may be higher than the second priority of the power storage device 120 that executes the second control while securing the supplyable amount for the first control (hereinafter, criterion 2-D). The second priority of the power storage device 120 that executes the second control while securing the supplyable amount for the first control may be higher than the second priority of the power storage device 120 that executes the second control so as to reduce an error with respect to the planned value of the power demand of the facility 100 (hereinafter, criterion 2-E).

[0066] Here, the first priority and the second priority are priorities for determining the order of priority of the power storage device 120 identified as the target power storage device 120 to be used in the first control. Therefore, it should be noted that the second priority is not the priority of the power storage device 120 to be used in the second control, but the priority of the power storage device 120 to be used in the first control. The priority of the power storage device 120 to be used in the second control may be considered to be in the reverse order of the priority of the power storage device 120 to be used in the first control (i.e., the second priority).

[0067] Third, the control unit 230 determines the priority order of the power storage device 120 based on at least one of the first priority order and the second priority order. That is, the control unit 230 determines the priority order of the power storage device 120 based on one or more criteria selected from among the criteria 1-A and the criteria 2A to 2E.

[0068] Here, the control unit 230 may identify a target power storage device 120 from among the power storage devices 120 that wish to participate in the first control. The control unit 230 may identify a target power storage device 120 for each fluctuation range of the frequency of the power grid 12 for which the first control is requested. The target power storage device 120 for each fluctuation range may be identified based on the priority order of the power storage devices 120 (i.e., at least one of the first priority and the second priority).

[0069] 6, a case will be illustrated in which the available supply amount (total) of the power storage device 120 managed by the power management server 200 is ±1000 kW, the frequency of the power grid 12 is 50 Hz, and the adjustment rate is 5%. In such a case, when the frequency fluctuation is 2.5 Hz, the power storage device 120 managed by the power management server 200 is required to discharge 1000 kW of power. Although not particularly limited, a predetermined range (-0.01 to +0.01 Hz) may be a dead band.

[0070] Here, the control unit 230 specifies the power storage device #A as the target power storage device 120 to be used in the fluctuation range of -0.2 Hz or less and -0.2 to 1.25 Hz, specifies the power storage device #B as the target power storage device 120 to be used in the fluctuation range of -0.2 Hz or less and 1.25 to 2.0 Hz, and specifies the power storage device #C as the target power storage device 120 to be used in the fluctuation range of -0.2 Hz or less and 2.0 to 2.5 Hz. As for the priority used in the first control, the priority of the power storage device #A is higher than the priority of the power storage device #B, and the priority of the power storage device #B is higher than the priority of the power storage device #C. Each of the power storage devices #A to #C may include at least one target power storage device 120. The power storage devices #A to #C may be considered as groups #A to #C.

[0071] Under such a premise, the control unit 230 specifies the target power storage devices 120 belonging to each of the groups #A to #C based on the first priority and the second priority. For example, the control unit 230 may specify, as the target power storage devices 120 belonging to the group #A, the power storage devices 120 that positively desire to contribute to the first control and execute the second control as determined by the planned value of the power demand of the facility 100. The control unit 230 may specify, as the target power storage devices 120 belonging to the group #B, the power storage devices 120 that positively desire to contribute to the first control and execute the second control while securing the supplyable amount for the first control. The control unit 230 may specify, as the target power storage devices 120 belonging to the group #C, the power storage devices 120 that do not positively desire to contribute to the first control and execute the second control so as to reduce an error with respect to the planned value of the power demand of the facility 100.

[0072] For example, in a case where the available supply amount of the target power storage device 120 belonging to group #A is ±500 kW, the target power storage device 120 belonging to group #A executes the first control in a fluctuation range of -0.2 or less and -0.2 to 1.25 Hz, as shown in Fig. 7. In such a case, it should be noted that the adjustment rate (positive side) applied to the target power storage device 120 belonging to group #A needs to be changed from 5% to 2.5%.

[0073] For example, in a case where the available supply amount of the target power storage device 120 belonging to group #B is ±300 kW, the target power storage device 120 belonging to group #B executes the first control in a fluctuation range of less than -0.2 and 1.25 to 2.0 Hz, as shown in Fig. 8. In such a case, it should be noted that the adjustment rate (positive side) applied to the target power storage device 120 belonging to group #B needs to be changed from 5% to 4%, and 0 to 1.25 Hz needs to be set as the dead band.

[0074] For example, in a case where the available supply amount of the target power storage device 120 belonging to group #C is ±300 kW, the target power storage device 120 belonging to group #C executes the first control in a fluctuation range of less than -0.2 and 2.0 to 2.5, as shown in Fig. 9. In such a case, it should be noted that it is necessary to leave the adjustment rate (positive side) applied to the target power storage device 120 belonging to group #C unchanged at 5%, and to set 0 to 2.0 Hz as the dead band.

[0075] In the example shown in Figures 7 to 9, in the fluctuation range of -0.2 to 0 Hz, only the target power storage devices 120 belonging to group #A execute the first control, and only the target power storage devices 120 belonging to groups #B and #C do not need to execute the first control.

[0076] Here, focusing on the fluctuation range of -0.2 to 0 Hz, the behavior of the target power storage devices 120 belonging to groups #A to #C will be described. Here, the reference value is the charge / discharge amount of the power storage device 120 used to calculate the available supply amount, and the actual value is the charge / discharge amount of the power storage device 120 obtained as a result of the first control or the second control.

[0077] As shown in Fig. 10, the target power storage devices 120 belonging to group #A execute the first control based on the reference value, and therefore the performance value may vary based on the reference value in order to maintain the frequency of the power grid 12. On the other hand, the target power storage devices 120 belonging to groups #B and #C have room to execute the second control, and the performance value may deviate from the reference value due to the second control. That is, the target power storage devices 120 belonging to groups #B and #C can be effectively used for the second control. Note that Fig. 10 illustrates a case in which the frequency deviation falls within the dead band (e.g., -0.1 to 1.0 Hz) before time t, and falls below -0.2 Hz after time t.

[0078] Here, the frequency of switching between charging and discharging required in the second control may be lower than the frequency of switching between charging and discharging required in the first control. In such a configuration, deterioration of the target power storage devices 120 belonging to group #A is unavoidable, but deterioration of the target power storage devices 120 belonging to groups #B and #C can be suppressed. (Power management method)

[0079] A power management method according to an embodiment will be described below. In Fig. 11, a case where the AC and the RA are separate entities is illustrated. The above-mentioned power management server 200 may be the RA.

[0080] As shown in FIG. 11, in step S10, the AC transmits an arbitration rate to the RA.

[0081] In step S11, the RA transmits a query to the facility 100. The query is a message requesting the first behavior information and the second behavior information.

[0082] In step S12, the RA receives a response to the inquiry from the facility 100. The response includes the first behavior information and the second behavior information.

[0083] In step S13, the RA determines the priority order of the power storage devices 120 identified as the target power storage devices 120 to be used in the first control, based on the first priority and the second priority. The RA may identify the target power storage devices 120 for each fluctuation range of the frequency of the power grid 12.

[0084] In step S14, the RA sets (transmits) an adjustment rate to be applied to the target power storage device 120 identified for each fluctuation range.

[0085] In step S20, the AC transmits a command regarding adjustment of the frequency of the power system 12 (adjustment command) to the RA.

[0086] In step S21, the RA transmits a control command for the power storage device 120 to the facility 100 for adjusting the frequency of the power grid 12.

[0087] In step S22, the target power storage device 120 installed in the facility 100 executes the first control or the second control.

[0088] In step S23, the RA receives the results (performance) of the first control and the second control from the facility 100.

[0089] In step S24, the RA may re-determine the priority order of the power storage devices 120 identified as the target power storage devices 120 to be used in the first control, based on the results (performance) of the first control and the second control. The RA may re-identify the target power storage devices 120 for each fluctuation range of the frequency of the power grid 12.

[0090] For example, the RA may execute a process of lowering the priority of a target power storage device 120 whose charging capacity or discharging capacity is smaller than a threshold value. Alternatively, the RA may execute a process of lowering the priority of a target power storage device 120 installed in a facility 100 whose error from the planned value of power demand is larger than a threshold value.

[0091] In step S25, the RA may re-set (transmit) the adjustment rate to be applied to the target power storage device 120 identified for each fluctuation range.

[0092] Thereafter, the processes of steps S22 to S25 may be repeated.

[0093] In addition, in FIG. 11, a case where the adjustment rate is transmitted from the AC to the RA in step S10 is illustrated, but the adjustment rate may be determined in advance and manually set in the RA.

[0094] (Action and Effects) In the embodiment, the power management server 200 determines the priority order of the power storage device 120 identified as the target power storage device 120 based on at least one of the first priority of the power storage device 120 for the first control and the second priority of the power storage device 120 for a second control other than the first control. With this configuration, it is possible to secure the power storage device 120 that can execute the second control, compared to a case in which the power storage device 120 that wishes to participate in the first control uniformly executes the first control, and it is possible to appropriately utilize the power storage device 120 when both the first control and the second control are taken into consideration.

[0095] In an embodiment, the power management server 200 may identify the target power storage device 120 for each fluctuation range of the frequency of the power grid 12. According to such a configuration, it is possible to appropriately utilize the power storage device 120 while maintaining the frequency of the power grid 12 by the first control.

[0096] [Change Example 1] Modification 1 of the embodiment will be described below, focusing mainly on the differences from the above-described embodiment.

[0097] In the embodiment, the case has been exemplified where group #A corresponds to −0.2 Hz or less and a fluctuation range of −0.2 to 1.25 Hz, and group #B corresponds to −0.2 Hz or less and a fluctuation range of 1.25 to 2.0 Hz.

[0098] In contrast, in modification example 1, as shown in FIG. 12, a portion of group #A (#A-1) and a portion of group #B (#B-1) may correspond to a fluctuation range of -0.2 Hz or less and -0.2 to 1.25 Hz, and a portion of group #A (#A-2) and a portion of group #B (#B-2) may correspond to a fluctuation range of -0.2 Hz or less and 1.25 to 2.0 Hz.

[0099] In this way, the target power storage devices 120 for each fluctuation range of the frequency of the power grid 12 may be specified relatively freely without being restricted only by the priority order of the power storage devices 120.

[0100] [Change Example 2] Modification 2 of the embodiment will be described below, focusing mainly on the differences from the above-described embodiment.

[0101] In the second modification, a variation in the method of determining the priority order of power storage devices 120 will be described.

[0102] First, the power management server 200 may determine the first priority or the second priority based on the difference between a current SoC (State of Charge) and a target SoC assumed by executing the first control. For example, the larger the difference between the current SoC and the target SoC, the higher the first priority or the second priority may be. With this configuration, it is possible to reduce the frequency of switching between charging and discharging the power storage device 120.

[0103] Secondly, the power management server 200 may specify the first priority or the second priority based on the degree of deterioration of the power storage device 120. For example, the smaller the degree of deterioration, the higher the first priority or the second priority. With this configuration, it is possible to suppress a situation in which the deterioration of the power storage device 120 advances due to the first control.

[0104] Thirdly, the power management server 200 may determine the first priority based on an upper limit of the amount of change in the charging power or discharging power of the power storage device 120 per unit time. For example, the larger the upper limit of the amount of change, the higher the first priority. With this configuration, the responsiveness of the power storage device 120 used in the first control to a control command is improved, and the accuracy of adjusting the frequency of the power grid 12 is improved.

[0105] [Other embodiments] Although the present invention has been described by the above-mentioned embodiment, the description and drawings forming a part of this disclosure should not be understood as limiting the present invention. From this disclosure, various alternative embodiments, examples and operating techniques will become apparent to those skilled in the art.

[0106] In the above disclosure, the case where the distributed power source used in the first control and the second control is the power storage device 120 has been exemplified. However, the above disclosure is not limited to this. The distributed power source used in the first control and the second control may be any distributed power source that is capable of adjusting output power, such as the fuel cell device 130.

[0107] Although not particularly mentioned in the above disclosure, the priority order of the power storage device 120 corresponding to the + side fluctuation range may be different from the priority order of the power storage device 120 corresponding to the - side fluctuation range. The priority order of the power storage device 120 corresponding to the - side fluctuation range may be determined without determining the priority order of the power storage device 120 corresponding to the + side fluctuation range. The priority order of the power storage device 120 corresponding to the + side fluctuation range may be determined without determining the priority order of the power storage device 120 corresponding to the - side fluctuation range.

[0108] In the above disclosure, a case in which the first control is autonomously executed by the power storage device 120 has been exemplified. However, the above disclosure is not limited to this. The first control may be autonomously executed within the facility 100, and may be autonomously executed under the control of the EMS 160.

[0109] Although not specifically mentioned in the above disclosure, the priority order of the power storage devices 120 may be determined for each facility 100. In such a case, the target power storage device 120 may be read as the target facility 100 in which the power storage device 120 is installed. [Explanation of symbols]

[0110] 1...power management system, 11...network, 12...power system, 100...facility, 110...solar cell device, 120...power storage device, 121...BT, 122...monitoring section, 123...control section, 130...fuel cell device, 140...load device, 160...EMS, 190...measuring device, 200...power management server, 210...communication section, 220...management section, 230...control section

Claims

1. A management unit that manages distributed power sources installed in each of two or more facilities connected to the power grid; a control unit that identifies a target distributed power source to be used in a first control for maintaining a frequency of the power grid, The control unit is a power management device that determines the priority of the distributed power source identified as the target distributed power source based on at least one of the first priority of the distributed power source regarding the first control and the second priority of the distributed power source regarding a second control other than the first control.

2. The power management device according to claim 1 , wherein the second control is control related to management of power demand in a facility in which the distributed power source is installed.

3. 3 . The power management device according to claim 1 , wherein the control unit is configured to identify the target distributed power source for each fluctuation range of the frequency of the power grid for which the first control is required. 4 .

4. 4. The power management device according to claim 1, wherein the first priority is defined by an element indicating whether or not the distributed power source actively desires to contribute to the first control.

5. 5. The power management device of claim 1, wherein the second priority is defined by at least one of the following elements: an element indicating whether to execute the second control while ensuring the amount of power that the distributed power source can supply for the first control; an element indicating whether to execute the second control as determined by a planned value of power demand for the facility in which the distributed power source is installed; and an element indicating whether to execute the second control so as to reduce an error relative to the planned value of power demand for the facility.

6. 6. The power management device according to claim 1, wherein the control unit is configured to identify the target distributed power source from among distributed power sources that wish to participate in the first control.

7. The power management device according to claim 1 , wherein the distributed power sources include at least a power storage device.

8. Step A of managing distributed power sources installed in each of two or more facilities connected to a power grid; and a step B of identifying a target distributed power source to be used in a first control for maintaining a frequency of the power grid, The power management method includes a step of determining a priority order of the distributed power source identified as the target distributed power source based on at least one of a first priority order of the distributed power source regarding the first control and a second priority order of the distributed power source regarding a second control other than the first control.

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