Power management server and power management method

Abstract

To provide a power management server and a power management method capable of suppressing momentary disturbances in demand-and-supply balance of a power system.SOLUTION: A power management server includes: a receiving unit that receives an adjustment message for adjusting a demand-and-supply balance of a power system; a management unit that manages two or more devices; a control unit that determines an individual adjusted power amount to be adjusted by each of the two or more devices and start timing for starting power adjustment of each of the two or more devices so that the total adjusted power amount requested by the adjustment message is adjusted; and a transmitting unit that transmits a control message including an information element for specifying the individual adjusted power amount and the start timing, wherein the control unit determines the start timing different in each of the two or more devices.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] Conventionally, there has been known a mechanism (for example, VPP: Virtual Power Plant) in which a business operator such as a resource aggregator adjusts the power of a facility by using a control message such as a demand response in order to adjust the supply and demand balance of a power grid.

[0003] In the above-mentioned mechanism, the individual adjustment power amount to be requested to each facility is determined so that the total adjustment power amount requested to be adjusted as a resource aggregator by the control message is adjusted. For example, when determining the individual adjustment power amount of each facility, the adjustable amount of each facility is referenced (for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2016-135040 A [Patent Document 2] JP 2018-190115 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned system, a power meter (e.g., a smart meter) is used that transmits power information of the facility at predetermined time intervals (e.g., 30 minutes), and it is assumed that adjustment of the supply and demand balance of the power system is performed at the minimum unit of the predetermined time interval.

[0006] Under such an assumption, the facility only needs to adjust the power (instantaneous power (kW)) so that the individual adjustment power amount (integrated power (kWh)) is adjusted for the entire predetermined time interval. In other words, the facility does not need to continue to adjust the power at a constant level throughout the entire predetermined time interval.

[0007] As a result of intensive research, the inventors have found that, based on the above findings, it is possible to adjust the instantaneous power of the power so that the integrated power reaches the individual adjustment power amount early within a predetermined time interval. If the facility operates in this way, the power that is instantaneously adjusted within the predetermined time interval will be concentrated in the first half of the predetermined time interval, which will disrupt the supply and demand balance of the power system.

[0008] Therefore, the present invention has been made to solve the above-mentioned problems, and aims to provide a power management server and a power management method that make it possible to suppress momentary disruptions to the supply and demand balance of a power system. [Means for solving the problem]

[0009] A power management server according to a first feature includes a receiving unit that receives an adjustment message for adjusting the supply and demand balance of a power system, a management unit that manages two or more devices, a control unit that determines an individual adjustment power amount to be adjusted by each of the two or more devices and a start timing for each of the two or more devices to start power adjustment so that a total adjustment power amount requested by the adjustment message is adjusted, and a transmitting unit that transmits a control message including information elements that specify the individual adjustment power amount and the start timing, and the control unit determines the start timing, which differs for each of the two or more devices.

[0010] A power management server according to a second feature includes a receiving unit that receives an adjustment message for adjusting the supply and demand balance of a power system, and a transmitting unit that transmits a control message to two or more gateway devices that respectively control equipment, and the control message includes an information element that specifies the adjustment power that the equipment should continuously adjust so that the total amount of adjustment power requested by the adjustment message is adjusted, and an information element that specifies the duration for which the adjustment power should be maintained.

[0011] A power management method according to a third feature includes a step A of receiving an adjustment message for adjusting the supply and demand balance of a power system, a step B of determining an individual adjustment power amount to be adjusted by each of two or more devices and a start timing for each of the two or more devices to start power adjustment so that a total adjustment power amount requested by the adjustment message is adjusted, and a step C of transmitting a control message including information elements that specify the individual adjustment power amount and the start timing, wherein the step B includes a step of determining the start timing that differs for each of the two or more devices.

[0012] A power management method according to a fourth feature includes a step A of receiving an adjustment message for adjusting the supply and demand balance of a power system, and a step B of transmitting a control message to two or more gateway devices that respectively control equipment so that a total amount of adjustment power requested by the adjustment message is adjusted, and includes an information element that specifies the adjustment power that the equipment should continuously adjust so that the total amount of adjustment power requested by the adjustment message is adjusted, and an information element that specifies a duration for which the adjustment power should be maintained. Effect of the Invention

[0013] According to the present invention, it is possible to provide a power management server and a power management method that are capable of suppressing momentary disruptions to the supply and demand balance of a power system. [Brief description of the drawings]

[0014] [Figure 1]FIG. 1 is a diagram showing a power management system 100 according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing the lower level server 20 according to the embodiment. [Diagram 3] FIG. 3 is a diagram illustrating an example of adjustment of the supply and demand balance in a power system according to the embodiment. [Figure 4] FIG. 4 is a diagram illustrating an example of adjustment of the supply and demand balance in a power system according to the embodiment. [Diagram 5] FIG. 5 is a diagram illustrating an example of adjustment of the supply and demand balance in a power system according to the embodiment. [Figure 6] FIG. 6 is a diagram illustrating a power management method according to an embodiment. [Figure 7] FIG. 7 is a diagram showing an example of adjustment of the supply and demand balance in a power system according to the first modification. [Figure 8] FIG. 8 is a diagram showing an example of adjustment of the supply and demand balance in a power system according to the first modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] 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.

[0016] [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 facility 10, a lower server 20, and an upper server 30. The facility 10, the lower server 20, and the upper server 30 are connected by a network 120. The network 120 is the Internet. The network 120 may include a dedicated line such as a VPN (Virtual Private Network), or may include a mobile communication network.

[0017] The facility 10 has a power storage device 210, a load device 220, a power meter 230, and an EMS (Energy Management System) 240. Although not particularly limited, the facility 10 may be a non-commercial facility such as a residence, or a commercial facility such as an office or a store. The facility 10 may be a factory. Although one facility 10 is illustrated in FIG. 1 for the sake of simplicity of explanation, two or more facilities 10 may be provided.

[0018] The power storage device 210 is a distributed power source that charges and discharges power. The power storage device 210 is an example of a device managed by the lower level server 20. The power storage device 210 may be an example of a distributed power source used in a VPP (Virtual Power Plant). For example, the power storage device 210 is configured by a PCS and a power storage cell.

[0019] The load device 220 is a device that consumes power. The load device 220 may be an example of a device managed by the lower level server 20. For example, the load device 220 is an air conditioner, a lighting device, an AV (Audio Visual) device, or the like.

[0020] The power meter 230 is a power meter that measures forward flow power from the power grid to the facility 10 and reverse flow power from the facility 10 to the power grid. For example, the power meter 230 may be a power meter certified by a third party. The power meter 230 may be a smart meter belonging to the upper server 30. The power meter 230 may have a function of transmitting the measurement value of the power meter 230 at a predetermined transmission interval (e.g., 30 minutes). The measurement value of the power meter 230 may be transmitted to the EMS 240, may be transmitted to the lower server 20, or may be transmitted to the upper server 30.

[0021] The EMS 240 is a device that manages power in the facility 10. The EMS 240 may control the operation state of the power storage device 210 provided in the facility 10, and may control the operation state of the load device 220 provided in the facility 10. The EMS 240 may be referred to as a GW (Gateway) controller.

[0022] In the embodiment, communication between the lower server 20 and the EMS 240 is performed according to a first protocol. On the other hand, communication between the EMS 240 and each device (for example, the power storage device 210, the load device 220, and the power meter 230) may be performed according to a second protocol that may be 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. For example, both the first protocol and the second protocol may be unique dedicated protocols, as long as 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.

[0023] The downstream server 20 is an example of a power management server that manages two or more devices. The downstream server 20 is a server managed by a business operator such as a power generation business operator, a power transmission and distribution business operator, a retail business operator, or a resource aggregator. The resource aggregator is a power business operator that provides reverse flow power to the power generation business operator, the power transmission and distribution business operator, the retail business operator, and the like in a VPP. The resource aggregator may be a power business operator that generates reduced power of the forward flow power (power consumption) of the facility 10 managed by the resource aggregator.

[0024] The upper server 30 is an example of a server that manages the balance of power supply and demand in a power system. The upper server 30 is an entity that provides infrastructure such as a power system, and may be a server managed by a power generation company or a power transmission and distribution company. The upper server 30 may be a server managed by an aggregator controller that controls a resource aggregator.

[0025] The upper server 30 transmits an adjustment message requesting adjustment of the supply and demand balance of the power system to the lower server 20. The adjustment message may include a message requesting a reduction in the power demand of the power system (a DR (Demand Response) message). The adjustment message may include a message requesting a reduction in the power supply of the power system (an output curtailment message).

[0026] In the embodiment, the communication between the lower server 20 and the upper server 30 is performed according to a third protocol. For example, a protocol conforming to Open ADR can be used as the third protocol. When a protocol conforming to Open ADR is used as the first protocol, the third protocol may be the same as the first protocol.

[0027] (Sub-server) The following describes a subordinate server according to an embodiment. As shown in Fig. 2, the subordinate server 20 includes a communication unit 21, a management unit 22, and a control unit 23. As described above, the subordinate server 20 is an example of a power management server that manages two or more devices.

[0028] The communication unit 21 is configured by a communication module. The communication module may be a wireless communication module conforming to a standard such as IEEE802.11a / b / g / n, ZigBee, Wi-SUN, LTE, or 5G, or may be a wired communication module conforming to a standard such as IEEE802.3.

[0029] In the embodiment, the communication unit 21 constitutes a receiving unit that receives an adjustment message from the upper server 30. The adjustment message transmitted to the lower server 20 is a message transmitted to an area including devices managed by the lower server 20. As described above, the adjustment message may be a DR message or an output suppression message.

[0030] Here, the adjustment message includes an information element that specifies an adjustment target period for adjusting the supply and demand balance of the power grid. A predetermined time interval may be defined as the minimum unit of the adjustment target period. The predetermined time interval may be the same as a predetermined transmission interval at which the power meter 230 transmits a measurement value. The adjustment result of the supply and demand balance of the power grid may be verified by the measurement value transmitted from the power meter 230.

[0031] Furthermore, the adjustment message includes an information element that specifies the total amount of power to be adjusted that requests adjustment of the supply and demand balance of the power system. The total amount of power to be adjusted may be represented by an integrated value of the power to be adjusted in the period to be adjusted. The total amount of power to be adjusted may be determined based on the baseline power. The baseline power may be an average value of the power demand for a certain period before the transmission of the adjustment message. The certain period may be determined according to the actual situation of the negawatt trading, or may be determined between the lower server 20 and the upper server 30. Alternatively, the total amount of power to be adjusted may be determined based on a supply and demand forecast value of the power system.

[0032] For example, assuming a case in which the instantaneous value of the adjustment power to be adjusted from the baseline power is determined based on the baseline power, the total amount of adjustment power may be represented by the accumulated value of the difference between the supply and demand forecast value of the power system and the instantaneous value of the adjustment power.

[0033] The total adjustment power amount may be an information element that specifies a range defined by a lower limit value of the total adjustment power amount and an upper limit value of the total adjustment power amount. The information element may include a lower limit value of the total adjustment power amount and an upper limit value of the total adjustment power amount, and may include a target power of the total adjustment power amount and a relative value based on the target power (e.g., ±XX% or ±YYkWh). If the relative value is determined in advance, the relative value may not be included in the adjustment message.

[0034] In the embodiment, the communication unit 21 transmits a control message for controlling the power storage device 210. The communication unit 21 may transmit the control message to the power storage device 210, or may transmit the control message to the EMS 240 that controls the power storage device 210.

[0035] The management unit 22 is configured by a storage medium such as a non-volatile memory and / or a HDD. The management unit 22 manages information related to two or more power storage devices 210. The two or more power storage devices 210 may be provided in the same facility 10 or may be provided in different facilities 10. For example, the management unit 22 may manage the discharge power value of the power storage device 210, or may manage the charge power value of the power storage device 210. These power values ​​may be defined by a minimum value and a maximum value. These power values ​​may be interpreted as the rated power value of the power storage device 210 (PCS). The management unit 22 may manage the dischargeable capacity of the power storage device 210, or may manage the chargeable capacity of the power storage device 210. These capacities may be determined by the rated capacity and storage capacity of the power storage device 210 (power storage cell). The discharge power value, the charge power value, the dischargeable capacity, and the chargeable capacity may be collectively referred to as power storage information.

[0036] The control unit 23 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.

[0037] In the embodiment, the control unit 23 determines the individual adjustment amount of power to be adjusted by each of the two or more power storage devices 210 and the start timing at which each of the two or more power storage devices 210 starts power adjustment, so that the total adjustment amount of power requested by the adjustment message is adjusted. The control unit 23 determines a different start timing for each of the two or more power storage devices 210. The control unit 23 may determine the individual adjustment amount of power and the start timing based on the power storage information of each power storage device 210. The individual adjustment amount of power may be represented by an integrated value of power adjusted by the power storage device 210.

[0038] The control unit 23 may determine different start timings for two or more power storage devices 210 within a predetermined time interval. The control unit 23 may determine the individual adjustment amount of power and the start timing based on a lower limit value of the total adjustment amount of power. The control unit 23 may determine the individual adjustment amount of power and the start timing based on an upper limit value of the total adjustment amount of power.

[0039] Here, when the device for adjusting the supply and demand balance of the power system is the power storage device 210, the control unit 23 determines the start timing for starting at least one of the discharging operation and the charging operation of the power storage device 210. In such a case, the control unit 23 determines the duration and the magnitude of power of at least one of the discharging operation and the charging operation of the power storage device 210.

[0040] For example, in a case where a reduction in the power demand of the power grid is requested, the control unit 23 determines, for each of two or more power storage devices 210, the start timing for starting the discharging operation of the power storage device 210, the magnitude of the discharge power of the power storage device 210, and the duration of the discharging operation of the power storage device 210. The magnitude of the discharge power may be represented by an instantaneous value of the discharge power. The duration of the discharging operation may be represented by an end timing for ending the discharging operation, by a time for which the discharging operation continues, or by an individual adjustment amount of power. Since the individual adjustment amount of power is represented by a result of multiplying the instantaneous value of the discharge power and the duration of the discharging operation, the duration of the discharging operation is represented by a result of dividing the individual adjustment amount of power by the instantaneous value of the discharge power.

[0041] Similarly, in a case where a reduction in power supply from the power grid is requested, the control unit 23 determines, for each of the two or more power storage devices 210, the start timing for starting the charging operation of the power storage device 210, the magnitude of the charging power of the power storage device 210, and the duration of the charging operation of the power storage device 210. The magnitude of the charging power may be represented by an instantaneous value of the charging power. The duration of the charging operation may be represented by an end timing for ending the charging operation, by a time for which the charging operation continues, or by an individual adjustment amount of power. The individual adjustment amount of power is represented by a result of multiplying the instantaneous value of the charging power and the duration of the charging operation, and therefore the duration of the charging operation is represented by a result of dividing the individual adjustment amount of power by the instantaneous value of the charging power.

[0042] Furthermore, the control unit 23 may determine the start timing so that the discharging operation of the power storage device 210 is performed throughout the entire adjustment target period for which power adjustment is requested by the adjustment message. In other words, the control unit 23 may determine the start timing of each of the two or more power storage devices 210 so that the discharging operation of the two or more power storage devices 210 is not interrupted.

[0043] For example, the control unit 23 aligns the end timing of the discharge operation of the nth controlled power storage device 210 with the start timing of the discharge operation of the n+1th controlled power storage device 210. The end timing and the start timing may be aligned so that the end timing of the nth discharge operation is 8:59:59 and the start timing of the n+1th discharge operation is 9:00:00, or the end timing of the nth discharge operation is 9:00:00 and the start timing of the n+1th discharge operation is 9:00:00. That is, the adjustment target period may include a momentary blank time (for example, 1 second) of the discharge operation, or may not include a momentary blank time of the discharge operation. From the viewpoint of appropriately maintaining the supply and demand balance of the power system, it is preferable that the momentary blank time of the discharge operation is not included. Note that the above-mentioned times such as 8:59:59 or 9:00:00 may be considered to be synonymous with timing.

[0044] Similarly, control unit 23 may determine the start timing so that the charging operation of power storage device 210 is performed throughout the entire adjustment target period for which power adjustment is requested by the adjustment message. In other words, control unit 23 may determine the start timing for each of two or more power storage devices 210 so that the charging operation of two or more power storage devices 210 is not interrupted.

[0045] For example, the control unit 23 aligns the end timing of the charging operation of the nth controlled power storage device 210 with the start timing of the charging operation of the n+1th controlled power storage device 210. The end timing and the start timing may be aligned so that the end timing of the nth charging operation is 8:59:59 and the start timing of the n+1th charging operation is 9:00:00, or the end timing of the nth charging operation is 9:00:00 and the start timing of the n+1th charging operation is 9:00:00. That is, the adjustment target period may include a momentary blank time (for example, 1 second) in the charging operation, or may not include a momentary blank time in the charging operation. From the viewpoint of appropriately maintaining the supply and demand balance of the power system, it is preferable that a momentary blank time in the charging operation is not included. Note that the above-mentioned times such as 8:59:59 or 9:00:00 may be considered to be synonymous with timing.

[0046] (Example of adjusting the supply and demand balance in the power grid) An example of adjusting the supply and demand balance of a power system according to an embodiment will be described below with reference to Figs. 3 to 5. In the following, a case will be illustrated in which power storage devices A to D are managed by a lower server 20 and a demand reduction in the power system is requested. A case will be illustrated in which the start timing of each power storage device is different within a predetermined time interval, which is the smallest unit of the period subject to adjustment. TS is the start timing of the predetermined time interval, and TE is the end timing of the predetermined time interval.

[0047] 3 to 5, the vertical axis represents discharge power, and the horizontal axis represents time. The upper limit value represents the time transition of the upper limit value of the instantaneous value of the total regulated power, and the lower limit value represents the time transition of the upper limit value of the instantaneous value of the total regulated power. The target value represents the time transition of the target value of the instantaneous value of the total regulated power. The target value may be an intermediate value between the upper limit value and the lower limit value. The range defined by the upper limit value and the lower limit value is specified by an information element included in the adjustment message received from the upper server 30.

[0048] As shown in Fig. 3, the lower server 20 determines TS as the start timing of power storage device A, and determines T1 as the end timing of power storage device A. The lower server 20 determines T1 as the start timing of power storage device B, and determines T2 as the end timing of power storage device B. The lower server 20 determines T2 as the start timing of power storage device C, and determines T3 as the end timing of power storage device C. The lower server 20 determines T3 as the start timing of power storage device D, and determines TE as the end timing of power storage device D. That is, the lower server 20 determines the start timings of two or more power storage devices 210 so that the discharging operation is not interrupted at a predetermined time interval.

[0049] Furthermore, the lower server 20 determines the discharge power of the power storage device A during the duration of the power storage device A (between TS and T1) so that the discharge power is between an upper limit value and a lower limit value. The lower server 20 determines the discharge power of the power storage device B during the duration of the power storage device B (between T1 and T2) so that the discharge power is between an upper limit value and a lower limit value. The lower server 20 determines the discharge power of the power storage device C during the duration of the power storage device C (between T2 and T3) so that the discharge power is between an upper limit value and a lower limit value. The lower server 20 determines the discharge power of the power storage device D during the duration of the power storage device D (between T3 and TE) so that the discharge power is between an upper limit value and a lower limit value.

[0050] In the embodiment, the power storage device 210 is configured to continue the discharging operation with the discharge power set by the lower level server 20 (EMS 240). Therefore, as shown in Fig. 3, the magnitude of the discharge power does not change during the duration of the discharging operation.

[0051] For example, in a case where the total regulated power amount in a predetermined time interval is 4 kWh / 30 minutes, a case where the total regulated power amount is equally allocated to each storage device will be illustrated. In such a case, the individual regulated power amount of each storage device is 1 kWh / 30 minutes. For example, for storage device A, the start timing may be 0 minutes (=TS), the end timing may be 9 minutes (=T1), the duration may be 9 minutes, and the magnitude of discharge power may be 6.67 kW. For storage device B, the start timing may be 9 minutes (=T1), the end timing may be 14 minutes (=T2), the duration may be 5 minutes, and the magnitude of discharge power may be 12 kW. For storage device C, the start timing may be 14 minutes (=T2), the end timing may be 22 minutes (=T3), the duration may be 8 minutes, and the magnitude of discharge power may be 7.5 kW. For power storage device D, the start timing may be 22 minutes (=T3), the end timing may be 22 minutes (=T4), the duration may be 30 minutes, and the magnitude of the discharge power may be 7.5 kW.

[0052] Under the premise shown in Fig. 3, the lower server 20 may determine the discharge power of each power storage device based on a lower limit value as shown in Fig. 4. In other words, the lower server 20 may determine the discharge power of each power storage device so as to conform to the lower limit value under the condition that the discharge power of each power storage device does not fall below the lower limit value during the duration of the power storage device. However, the lower server 20 may determine the discharge power of at least some of the power storage devices based on an upper limit value.

[0053] Under the premise shown in Fig. 3, the lower server 20 may determine the discharge power of each power storage device based on an upper limit value as shown in Fig. 5. In other words, the lower server 20 may determine the discharge power of each power storage device so as to conform to the upper limit value under the condition that the discharge power of each power storage device does not exceed the upper limit value during the duration of the power storage device. However, the lower server 20 may determine the discharge power of at least some of the power storage devices based on a lower limit value.

[0054] (Power management method) A power management method according to an embodiment will be described below. In Fig. 6, for the sake of simplicity, one facility 10 (power storage device 210) is illustrated as an example, but in reality, two or more power storage devices 210 are provided. The two or more power storage devices 210 may be provided in the same facility 10 or in different facilities 10.

[0055] 6, in step S10, the EMS 240 receives information related to the power storage device 210 (power storage information) from the power storage device 210. The power storage information may include a discharge power value, a charge power value, a dischargeable capacity, a chargeable capacity, etc. The EMS 240 may receive the power storage information periodically.

[0056] In step S11, the upper server 30 transmits an adjustment message to the lower server 20. The adjustment message includes an information element that specifies an adjustment target period for adjusting the supply and demand balance of the power system. The adjustment message includes an information element that specifies a total adjustment amount of power that is requested to adjust the supply and demand balance of the power system.

[0057] In step S12, the EMS 240 transmits the facility information to the lower level server 20. For example, the facility information includes the above-mentioned power storage information.

[0058] In step S13, the lower server 20 determines the individual adjustment power amount and start timing of the power storage device 210 based on the power storage information of the power storage device 210. Furthermore, the lower server 20 may determine the duration and power magnitude of at least one of the discharging operation and the charging operation of the power storage device 210.

[0059] In step S14, the lower server 20 transmits a control message to the EMS 240. The control message includes an information element that specifies the amount of power to be individually adjusted and the start timing of the power storage device 210. The control message may include an information element that specifies the duration and the magnitude of the power of the power storage device 210.

[0060] In step S15, the EMS 240 sets the operation mode of the power storage device 210 based on the control message. The operation mode may include a discharging operation, a charging operation, a standby operation, and the like. Such setting may be performed before the start of the adjustment target period, or after the start of the adjustment target period. The EMS 240 may set the start timing for starting the discharging operation or the charging operation. Alternatively, the EMS 240 may set the operation mode of the power storage device 210 at the start timing. The EMS 240 may set the magnitude of the discharging power or the charging power in setting the operation mode of the power storage device 210. The EMS 240 may set the duration of the discharging operation or the charging operation in setting the operation mode of the power storage device 210. The EMS 240 may set the end timing of the discharging operation or the charging operation in setting the operation mode of the power storage device 210. The power storage device 210 operates according to the contents set by the EMS 240.

[0061] In step S16, the power meter 230 transmits the measurement value of the power meter 230 to the EMS 240. The power meter 230 transmits the measurement value at a predetermined transmission interval.

[0062] In step S17, the EMS 240 transmits the measurement value of the power meter 230 to the lower server 20. When the EMS 240 receives the measurement value from the power meter 230, the EMS 240 may transmit the measurement value to the lower server 20. The process of step S17 may be omitted.

[0063] In step S18, the EMS 240 transmits a performance report of the power adjusted during the adjustment target period to the lower server 20. For example, the performance report may include an integrated value of the discharged power or charged power of the power storage device 210 provided in the facility 10. The performance report may include an integrated value for each predetermined time interval that is the smallest unit of the adjustment target period. If the lower server 20 can grasp the actual power adjusted during the adjustment target period from the measurement value received in step S17, the process of step S18 may be omitted.

[0064] In step S19, the lower server 20 transmits a performance report of the power adjusted during the adjustment target period to the upper server 30. For example, the performance report may include an integrated value of the discharge power or charge power of the power storage device 210 managed by the lower server 20. The performance report may include an integrated value for each predetermined time interval that is the smallest unit of the adjustment target period.

[0065] (Action and Effects) In the embodiment, the lower server 20 determines a different start timing for each of the two or more power storage devices 210 so that the total adjustment power amount is adjusted. With such a configuration, it is possible to prevent the discharge operation or charge operation of the two or more power storage devices 210 from being biased toward the first half of the adjustment target period (or the predetermined time interval). In other words, it is possible to prevent momentary disturbance of the supply and demand balance of the power system.

[0066] In an embodiment, the lower server 20 may determine the individual adjustment power amount and the start timing based on the lower limit value of the total adjustment power amount. With this configuration, when there are many power storage devices 210 with small adjustable power among the power storage devices 210 managed by the lower server 20, it is easy to appropriately balance the supply and demand of the power system. When the adjustable power of devices (e.g., load devices 220) other than the power storage devices 210 managed by the lower server 20 is large, it is easy to appropriately balance the supply and demand of the power system.

[0067] In an embodiment, the lower server 20 may determine the individual adjustment power amount and the start timing based on the upper limit value of the total adjustment power amount. With this configuration, when there are many power storage devices 210 with large adjustable power among the power storage devices 210 managed by the lower server 20, it is easy to appropriately balance the supply and demand of the power system. When the adjustable power of devices (e.g., load devices 220) other than the power storage devices 210 managed by the lower server 20 is small, it is easy to appropriately balance the supply and demand of the power system.

[0068] [Change Example 1] Modification 1 of the embodiment will be described below. Differences from the embodiment will be mainly described below.

[0069] In the embodiment, as described in FIG. 3 etc., the magnitude of the discharge power (or the charge power) does not change during the duration of the discharging operation (or the charging operation). In contrast, in Modification Example 1, the lower server 20 (communication unit 21) transmits a control message including an information element specifying two or more different start timings to one or more power storage devices 210. That is, in Modification Example 1, the magnitude of the discharge power (or the charge power) can change during the duration of the discharging operation (or the charging operation).

[0070] (Example of adjusting the supply and demand balance in the power grid) An example of adjusting the supply and demand balance of the power system according to Modification Example 1 will be described below with reference to Figures 7 to 8. In the following, as in Figures 3 to 5, a case will be illustrated in which the power storage devices A to D are managed by the lower server 20 and a demand reduction in the power system is requested. The symbols and the like shown in the figures are the same as those in Figures 3 to 5, and their description will be omitted.

[0071] First, a modification of FIG. 4 described above will be described. As shown in FIG. 7, the lower server 20 determines TS as the start timing of the power storage device A, determines Ta as the end timing of the power storage device A, and determines Ta as the start timing of the power storage device A and determines T1 as the end timing of the power storage device A. The lower server 20 may determine the discharge power of the power storage device A based on a lower limit value between TS and Ta, and may determine the discharge power of the power storage device A based on an upper limit value between Ta and T1. As with the power storage device A, two or more start timings may be determined for the power storage devices B to D. Compared with FIG. 4, Ta, Tb, Tc, and Td are determined as additional start timings. Ta, Tb, Tc, and Td may be considered as additional end timings.

[0072] Secondly, a modification of FIG. 5 will be described. As shown in FIG. 8, the lower server 20 determines TS as the start timing of the power storage device A, determines Ta as the end timing of the power storage device A, and determines Ta as the start timing of the power storage device A and determines T1 as the end timing of the power storage device A. The lower server 20 may determine the discharge power of the power storage device A based on an upper limit value between TS and Ta, and may determine the discharge power of the power storage device A based on a lower limit value between Ta and T1. As with the power storage device A, two or more start timings may be determined for the power storage devices B to D. Compared with FIG. 5, Ta, Tb, Tc, and Td are determined as additional start timings. Ta, Tb, Tc, and Td may be considered as additional end timings.

[0073] Here, the lower server 20 may determine two or more start timings before the start of the predetermined time interval, or may determine an additional start timing during the predetermined time interval. For example, an additional start timing may be determined when the power consumption of the load devices 220 in the facility 10 differs from the predicted value, causing a surplus or deficiency in the amount of individually adjusted power.

[0074] [Change Example 2] Modification 2 of the embodiment will be described below. Differences from the embodiment will be mainly described below.

[0075] In the embodiment, a case has been illustrated in which the discharging operation (or charging operation) of each power storage device 210 is not interrupted during the adjustment target period, but the embodiment is not limited to this.

[0076] For example, the discharging operation (or charging operation) of each power storage device 210 may be interrupted during the adjustment target period. The time during which the discharging operation (or charging operation) is interrupted may be shorter than a predetermined threshold. The predetermined threshold may be determined based on the time during which instantaneous fluctuations are allowed in the power system.

[0077] Alternatively, the discharging (or charging) operations of the power storage devices 210 may overlap during the adjustment period. The time during which the discharging (or charging) operations overlap may be shorter than a predetermined threshold. The predetermined threshold may be determined based on the time during which instantaneous fluctuations are allowed in the power system.

[0078] [Change Example 3] The third modification of the embodiment will be described below. Differences from the embodiment will be mainly described below.

[0079] In the embodiment, the case where the downstream server 20 determines the individual adjustment power amount and the start timing has been illustrated. In the third modification, the downstream server 20 may be expressed as performing the following operations.

[0080] Specifically, the lower server 20 includes a receiving unit (communication unit 21) that receives an adjustment message for adjusting the supply and demand balance of the power system, and a transmitting unit (communication unit 21) that transmits a control message to two or more gateway devices (hereinafter, EMS 240) that respectively control devices (hereinafter, power storage devices 210).The control message includes an information element that specifies the adjustment power that should be continuously adjusted by the power storage devices 210 so that the total amount of adjustment power requested by the adjustment message is adjusted, and an information element that specifies the duration for which the adjustment power should be maintained.

[0081] The regulated power may be represented by an instantaneous value of the regulated power (discharging power or charging power). Thus, the information element specifying the regulated power may include an information element indicating an instantaneous value of the discharging power or charging power. The duration may be represented by a time for which the power adjustment should be continued after the control message is received. Thus, the information element specifying the duration may include an information element indicating a time for which the power storage device 210 should continue the adjustment operation. In such a case, the power storage device 210 may start the adjustment operation (discharging operation or charging operation) in response to the reception of the control message and maintain the regulated power for the duration. The duration may be defined by a start timing and a duration. Thus, the information element specifying the duration may include an information element indicating a start timing (e.g., a start time) and a duration. In such a case, the power storage device 210 may start the adjustment operation at the start timing and maintain the regulated power for the duration. The duration may be defined by a start timing and an end timing. Thus, the information element specifying the duration may include an information element indicating a start timing (e.g., a start time) and an end timing (e.g., an end time). In such a case, the power storage device 210 may maintain the regulated power from the start timing to the end timing.

[0082] As in the embodiment, the lower server 20 may determine different start timings for two or more power storage devices 210 within a predetermined time interval. The lower server 20 may transmit a control message at different timings for two or more power storage devices 210 according to the start timings. The lower server 20 may determine different end timings for two or more power storage devices 210 within a predetermined time interval. The lower server 20 may transmit a control message instructing the stop of the adjustment operation at different timings for two or more power storage devices 210 according to the end timings.

[0083] [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.

[0084] In the embodiment, the facility 10 includes one power storage device 210. However, the embodiment is not limited to this. The facility 10 may include two or more power storage devices 210.

[0085] In the embodiment, a case has been exemplified in which the downstream server 20 controls the supply and demand balance of the power system on a per-power storage device 210 basis. However, the embodiment is not limited to this. The downstream server 20 may control the supply and demand balance of the power system on a per-facility 10 basis. In such a case, the power storage device 210 may be read as the facility 10.

[0086] In the embodiment, a case has been exemplified in which the device for adjusting the supply and demand balance of the power system is the power storage device 210. However, the embodiment is not limited to this. The device for adjusting the supply and demand balance of the power system may include a load device 220. The device for adjusting the supply and demand balance of the power system may include a distributed power source other than the power storage device 210. The distributed power source other than the power storage device 210 may include one or more distributed power sources selected from a solar cell device, a fuel cell device, a wind power generation device, a geothermal power generation device, a hydroelectric power generation device, and the like.

[0087] Although not specifically mentioned in the embodiment, the lower server 20 may switch between a first process for determining an individual adjustment power amount and a start timing based on a lower limit value of the total adjustment power amount and a second process for determining an individual adjustment power amount and a start timing based on an upper limit value of the total adjustment power amount. For example, the lower server 20 may switch between the first process and the second process based on a time zone of the adjustment target period. If the adjustment target period is nighttime and a charging operation of the power storage device 210 is scheduled after the adjustment target period, the lower server 20 may execute the second process in a request for reduction of the power demand of the power system (discharging operation of the power storage device 210). If the adjustment target period is evening and a discharging operation of the power storage device 210 is scheduled after the adjustment target period, the lower server 20 may execute the first process in a request for reduction of the power demand of the power system (discharging operation of the power storage device 210). From a similar viewpoint, the lower server 20 may switch between the first process and the second process based on a demand forecast of the power system in a time zone after the adjustment target period.

[0088] Although not specifically mentioned in the embodiment, at least some of the functions of the EMS 240 may be executed by a cloud server connected to the network 120. The EMS 240 may be considered to include a cloud server. [Explanation of symbols]

[0089] 10...facility, 20...subordinate server, 21...communication unit, 22...management unit, 23...control unit, 30...upper server, 100...power management system, 120...network, 210...power storage device, 220...load device, 230...power meter, 240...EMS

Claims

1. A receiver that receives an adjustment message for adjusting the supply and demand balance of the power grid; A management unit that manages two or more devices; a control unit that determines an individual adjustment power amount to be adjusted by each of the two or more devices and a start timing for each of the two or more devices to start power adjustment so that a total adjustment power amount requested by the adjustment message is adjusted; a transmitter for transmitting a control message including an information element for specifying the individual adjustment power amount and the start timing, a predetermined time interval is defined as a minimum unit for adjusting the supply and demand balance of the power system, The control unit determines the start timing different for each of the two or more devices during the predetermined time interval, The control unit determines the individual adjustment power amount and the start timing so as to be in line with a lower limit value of the total adjustment power amount during a first time period included in the specified time interval, and determines the individual adjustment power amount and the start timing so as to be in line with an upper limit value of the total adjustment power amount during a second time period included in the specified time interval.

2. The power management server according to claim 1 , wherein the total amount of adjustment power is an information element that specifies a range defined by a lower limit value of the total amount of adjustment power and an upper limit value of the total amount of adjustment power.

3. The power management server according to claim 1 , wherein the transmission unit transmits the control message including an information element that specifies two or more different start timings to one or more devices included in the two or more devices.

4. The two or more devices include a power storage device, The power management server according to claim 1 , wherein the control unit determines, as the start timing, a start timing for starting at least one of a discharging operation and a charging operation of the power storage device.

5. The power management server according to claim 4 , wherein the control unit determines a duration and a magnitude of power of at least one of a discharging operation and a charging operation of the power storage device.

6. 6. The power management server according to claim 5, wherein the control unit aligns an end timing for ending at least one of the discharging operation and the charging operation of the storage device to be controlled nth with a start timing for starting at least one of the discharging operation and the charging operation of the storage device to be controlled n+1th.

7. The power management server according to claim 5 or claim 6, wherein the control unit determines the start timing so that a discharging operation of the power storage device is performed throughout the entire adjustment target period for which power adjustment is requested by the adjustment message, and determines the start timing so that a charging operation of the power storage device is performed.

8. A step A of receiving an adjustment message for adjusting a supply and demand balance of a power grid; A step B of determining an individual adjustment power amount to be adjusted by each of two or more devices and a start timing for each of the two or more devices to start power adjustment so that a total adjustment power amount requested by the adjustment message is adjusted; C. transmitting a control message including information elements that specify the individual adjustment power amount and the start timing; a predetermined time interval is defined as a minimum unit for adjusting the supply and demand balance of the power system, The step B includes a step of determining different start timings for the two or more devices within the predetermined time interval, The power management method includes a step of determining the individual adjustment power amount and the start timing so as to be in line with a lower limit value of the total adjustment power amount during a first time period included in the specified time interval, and determining the individual adjustment power amount and the start timing so as to be in line with an upper limit value of the total adjustment power amount during a second time period included in the specified time interval.

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