Power management system and power management method

Abstract

To provide a power management system capable of promoting consumption of power generated by a photovoltaic power generation system.SOLUTION: A power management system 10 includes an acquisition unit 35 that acquires weather forecast information, and a control unit 37 that determines whether or not to discharge a storage battery system 22 that stores power generated by a photovoltaic power generation system 21 on the basis of a predicted power generation amount that is a predicted value of a power generation amount by the photovoltaic power generation system 21 on a target day, the predicted power generation amount being determined on the basis of the acquired weather forecast information, and performs discharge control on the basis of a determination result. The control unit 37 causes the SOC of the storage battery system 22 to reach the second value smaller than the first value from the first value by the predetermined time in the morning of the target day by performing the discharge control.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Patent Document 1 discloses a supply and demand control device that distributes the power generated by a solar power generation system to a power storage device and a heat source device such as a heat pump. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2011 / 086886 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention provides a power management system and the like that can promote consumption of power generated by a solar power generation system. [Means for solving the problem]

[0005] A power management system according to one embodiment of the present invention includes an acquisition unit that acquires weather forecast information, and a control unit that determines whether to discharge a storage battery system that stores electricity generated by the solar power generation system based on a predicted power generation amount, which is a predicted value of the amount of electricity generated by the solar power generation system on a target day determined based on the acquired weather forecast information, and performs discharge control based on the determination result.By performing the discharge control, the control unit causes the SOC (State Of Charge) of the storage battery system to reach a second value smaller than the first value from a first value by a predetermined time in the morning of the target day.

[0006] A power management method according to one embodiment of the present invention is a power management method executed by a computer, and includes an acquisition step of acquiring weather forecast information, and a control step of determining whether to discharge a storage battery system that stores electricity generated by the solar power generation system based on a predicted power generation amount, which is a predicted value of the amount of electricity generated by the solar power generation system on a target day determined based on the acquired weather forecast information, and performing discharge control based on the determination result, wherein by performing the discharge control, the SOC of the storage battery system reaches a second value smaller than the first value from a first value by a predetermined time in the morning of the target day.

[0007] A program according to one aspect of the present invention is a program for causing a computer to execute the power management method. [Effects of the Invention]

[0008] A power management system according to one aspect of the present invention can promote consumption of power generated by a solar power generation system. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing a functional configuration of a power management system according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an outline of the operation of the power management system according to the embodiment. [Figure 3] FIG. 3 is a sequence diagram of a first operation example of the power management system according to the embodiment. [Figure 4] FIG. 4 is a sequence diagram of a second operation example of the power management system according to the embodiment. [Figure 5] FIG. 5 is a flowchart of the determination operation of the judgment timing. [Figure 6] FIG. 6 is a diagram illustrating a first modification of the system configuration. [Figure 7] FIG. 7 is a diagram showing a second modification of the system configuration. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection forms, steps, and step order shown in the following embodiments are merely examples and are not intended to limit the present invention. Furthermore, among the components in the following embodiments, components not recited in independent claims will be described as optional components.

[0011] It should be noted that the drawings are schematic diagrams and are not necessarily strict illustrations. In addition, in the drawings, substantially the same components are denoted by the same reference numerals, and overlapping descriptions may be omitted or simplified.

[0012] (Embodiment) [composition] First, the configuration of a power management system according to an embodiment will be described below. Fig. 1 is a block diagram showing the functional configuration of a power management system according to an embodiment.

[0013] The power management system 10 shown in Fig. 1 is a system that is installed in a facility 60 and manages power. The facility 60 is, for example, a residence such as a detached house or an apartment building, but may also be a facility outside a residence such as an office building or a factory.

[0014] 1 , the power management system 10 includes a solar power generation system 21, a storage battery system 22, a power conditioner 23, a load 24, a power measurement device 25, a control device 30, a server device 40, and a weather information management server 50. The power management system 10 may further include a smart meter 26.

[0015] The solar power generation system 21 is an example of a distributed power source, and is a power generation system that generates power by converting sunlight into electrical energy. The power generated by the solar power generation system 21 is output to a power conditioner 23. Specifically, the solar power generation system 21 is realized by a PV (Photovoltaic) panel or the like.

[0016] The storage battery system 22 is an example of a distributed power source, and stores the power generated by the solar power generation system 21. That is, the storage battery system 22 is charged with the power generated by the solar power generation system 21. The storage battery system 22 also outputs (discharges) the stored power to the power conditioner 23. The storage battery system 22 is realized by a secondary battery such as a lithium-ion battery. Furthermore, the storage battery system 22 may be charged by the grid power supply 70.

[0017] The power conditioner 23 is a power conversion device and may also be called a PCS (Power Conditioning System), etc. The power conditioner 23 is realized by a power conversion circuit such as a DC-DC converter and a DC-AC converter.

[0018] The power conditioner 23 converts DC power obtained from the solar power generation system 21 and the storage battery system 22 into AC power and supplies it to the load 24. The power conditioner 23 can also supply AC power obtained from the system power supply 70 to the load 24.

[0019] In this embodiment, when the power generated by the solar power generation system 21 or the power discharged from the storage battery system 22 is being input to the power conditioner 23, the power conditioner 23 supplies AC power based on the generated power or the discharged power to the load 24. When the power generated by the solar power generation system 21 or the power discharged from the storage battery system 22 is not being input to the power conditioner 23, the power conditioner 23 supplies AC power obtained from the grid power supply 70 to the load 24.

[0020] Furthermore, the power conditioner 23 converts the DC power obtained from the solar power generation system 21 into DC power suitable for charging the storage battery system 22, and charges the storage battery system 22. In other words, the power conditioner 23 assists in storing the power generated by the solar power generation system 21 in the storage battery system 22.

[0021] The loads 24 are electrical appliances used by users of the facility 60 (or residents if the facility 60 is a residence). The loads 24 include lighting equipment, air conditioning equipment, and the like.

[0022] The power measurement device 25 measures the amount of power used by the load 24 (in other words, the amount of power consumed). Specifically, the power measurement device 25 measures the total amount of power used by the AC power supplied from the power conditioner 23 to the load 24 and the amount of power used by the AC power supplied from the system power supply 70 to the load 24. The power measurement device 25 is realized by, for example, a current sensor (CT: Current Transformer).

[0023] The smart meter 26 is placed directly under the grid power 70 and measures the total amount of power generated and consumed by the devices described above. The measured values ​​are directly transmitted by wireless communication or other means to the power company's smart meter management server (not shown) and the control device 30 (EMS (Energy Management System) controller) described next.

[0024] The control device 30 controls the storage battery system 22. Specifically, the control device 30 is an EMS controller having an energy management function, and manages the daily power usage in the facility 60 as history information. The control device 30 is not limited to an EMS controller, and may be another controller or a gateway device. The control device 30 includes an information processing unit 31, a storage unit 32, a first communication unit 33, and a second communication unit 34.

[0025] The information processing unit 31 performs information processing related to the control of the storage battery system 22. The information processing unit 31 is realized, for example, by a microcomputer, but may also be realized by a processor. The information processing unit 31 includes, as functional components, an acquisition unit 35, a prediction unit 36, and a control unit 37. The functions of the acquisition unit 35, the prediction unit 36, and the control unit 37 are realized, for example, by a microcomputer or a processor constituting the information processing unit 31 executing a computer program stored in the storage unit 32. Specific operations performed by the acquisition unit 35, the prediction unit 36, and the control unit 37 will be described later.

[0026] The storage unit 32 is a storage device that stores the computer program executed by the information processing unit 31, performance information on the amount of power generated in the past, history information on the amount of power used, etc. The storage unit 32 is realized by, for example, a semiconductor memory.

[0027] The first communication unit 33 is a communication circuit that enables the control device 30 to communicate with the solar power generation system 21, the storage battery system 22, the power measurement device 25, the smart meter 26, and the like via a local communication network. The first communication unit 33 is, for example, a wireless communication circuit that performs wireless communication, but may also be a wired communication circuit that performs wired communication. The communication standard used by the first communication unit 33 is, for example, ECHONET Lite (registered trademark), but the communication standard used by the first communication unit 33 is not particularly limited.

[0028] The second communication unit 34 is a communication circuit that enables the control device 30 to communicate with the server device 40 and the weather information management server 50 via the wide area communication network 80. The second communication unit 34 is, for example, a wireless communication circuit that performs wireless communication, but may also be a wired communication circuit that performs wired communication. There are no particular limitations on the communication standard used for communication by the second communication unit 34.

[0029] The server device 40 is a cloud server installed outside the facility 60. The server device 40 supports the control of the storage battery system 22 performed by the control device 30. For example, the server device 40 receives weather forecast information and provides the received weather forecast information to the control device 30. The server device 40 may cooperate with the control device 30 and execute some or all of the processing executed by the control device 30.

[0030] The weather information management server 50 is a cloud server installed outside the facility 60, and provides weather forecast information or past weather information to the server device 40. The weather information management server 50 may provide weather information to the control device 30 without going through the server device 40. The weather forecast information and the weather information each include solar radiation information, temperature information, etc.

[0031] [Operation Overview] In the power management system 10, the power generated by the solar power generation system 21 is supplied to the load 24. For example, when it is a sunny day during the day and the amount of power generated is sufficient, the load 24 operates using the power generated by the solar power generation system 21, and the surplus of the generated power (hereinafter also referred to as surplus power) is stored in the storage battery system 22.

[0032] On the other hand, on daytime days with bad weather or when there is a risk that the amount of power generated will not be sufficient to cover the power consumption of the load 24, power is also supplied to the load 24 from the battery system 22 or the power grid 70. In other words, the user of the facility 60 will purchase power from the power company.

[0033] In the power management system 10, the lower limit of the SOC (State Of Charge) of the storage battery system 22 is set to 40% in preparation for emergencies such as power outages. In other words, the lower limit of the SOC of the storage battery system 22 is set to 40% in order to maintain resilience to emergencies. Note that the value of 40% is an example. The lower limit of the SOC of the storage battery system 22 may be changeable by a user of the facility 60 via a user interface (not shown), for example.

[0034] Therefore, when the weather is bad during the day and the power generated by the solar power generation system 21 is insufficient to supply to the load 24, power is supplied from the storage battery system 22 to the load 24 as long as the SOC of the storage battery system 22 exceeds 40%. When the SOC of the storage battery system 22 drops to 40%, power is supplied to the load 24 from the grid power supply 70. In other words, the user of the facility 60 purchases power from the power company that manages the grid power supply 70.

[0035] The same applies after sunset: after sunset, when the SOC of the storage battery system 22 exceeds 40%, power is supplied from the storage battery system 22 to the load 24, and when the SOC of the storage battery system 22 drops to 40%, power is supplied from the grid power supply 70 to the load 24. In other words, after sunset, the storage battery system 22 discharges until the SOC of the storage battery system 22 reaches 40%.

[0036] As described above, in the power management system 10, the lower limit of the SOC is 40%, and the storage battery system 22 is generally discharged so that the SOC does not fall below 40%. If the lower limit of the SOC of the storage battery system 22 is fixed at 40% except in emergencies such as power outages, the amount of power that can be stored in the storage battery system 22 on a sunny day will be equivalent to an SOC of 60% at most. As a result, even on days with good weather and sufficient power generation, the amount of power stored in the storage battery system 22 will decrease, resulting in more time periods during which power is purchased from the grid power supply 70 and used, which reduces economic efficiency. Therefore, in order to increase the amount of power that can be stored in the storage battery system 22, the power management system 10 operates to control the SOC of the storage battery system 22 as follows.

[0037] Fig. 2 is a diagram showing an overview of the operation of controlling the SOC of the storage battery system 22. Fig. 2(a) shows the amount of power generated by the solar power generation system 21, the SOC of the storage battery system 22, and the power demand in the facility 60 on a day when the amount of power generation is predicted to be high (good weather). Fig. 2(b) shows the amount of power generated by the solar power generation system 21, the SOC of the storage battery system 22, and the power demand in the facility 60 on a day when the amount of power generation is predicted to be low (bad weather).

[0038] The power management system 10 predicts the amount of power generated by the photovoltaic power generation system 21 on a target day based on weather forecast information at a determination timing such as 3:00 AM (late night) on the target day. As shown in FIG. 2(a), when the predicted amount of power generation is high, the power management system 10 discharges the storage battery system 22 (causing the load 24 to consume the power stored in the storage battery system 22) to reduce the SOC of the storage battery system 22 from the lower limit of 40% to a further lower value of 10% by a predetermined time. Note that the value of 10% is an example. The target value for the lower limit of SOC when the predicted amount of power generation is high (a SOC value lower than the lower limit) may be changeable by a user of the facility 60, for example, via a user interface (not shown).

[0039] As a result, the SOC of the storage battery system 22 at the specified time becomes 10%, and the power that can be stored in the storage battery system 22 during the day increases to an SOC equivalent to 90%. The specified time is, for example, within one hour before or after sunrise.

[0040] 2(b), when the predicted power generation amount is low, the power management system 10 does not discharge the battery system 22 and maintains the SOC of the battery system 22 at the lower limit of 40%. As a result, the SOC of the battery system 22 at the specified time is 40%.

[0041] In this way, the power management system 10 performs discharge control to discharge the storage battery system 22 when it is predicted that the amount of power generated by the solar power generation system 21 will be large, thereby increasing the amount of power used (hereinafter also referred to as an increase in self-consumption) supplied from the solar power generation system 21 or the storage battery system 22 (i.e., distributed power sources). This allows the power management system 10 to achieve both an increase in self-consumption and the maintenance of resilience.

[0042] For example, when the solar power generation system 21 or the storage battery system 22 is owned by a consumer (a user of the facility 60), an increase in self-consumption reduces the use of power from the grid power supply 70, which has the advantage of reducing the consumer's electricity costs. Also, when the solar power generation system 21 and the storage battery system 22 are owned by a specific business operator rather than a consumer, such as in a PPA (Power Purchase Agreement) model, an increase in self-consumption has an advantage for the specific business operator.

[0043] [Example 1] Hereinafter, a first operational example of the battery system 22 will be described, including the discharge control described with reference to (a) of Fig. 2. Fig. 3 is a flowchart of the first operational example of the power management system 10.

[0044] As described above, after sunset on the day before the target day (the day for which the power generation amount is predicted), the storage battery system 22 discharges until the SOC reaches 40%, and stops discharging when the SOC reaches 40%. When the determination timing for a late-night time period (for example, a time period from midnight to 3:00 AM on the target day) arrives while the SOC of the storage battery system 22 is 40%, the acquisition unit 35 of the control device 30 acquires the latest weather forecast information from the weather information management server 50 via the second communication unit 34 (S11). The weather forecast information may be provided from the weather information management server 50 to the server device 40, in which case the acquisition unit 35 acquires the weather forecast information from the server device 40 via the second communication unit 34.

[0045] In addition, the memory unit 32 of the control device 30 has a regional code indicating the region to which the facility 60 belongs pre-stored (registered), and the acquisition unit 35 can acquire weather forecast information for the region to which the facility 60 belongs based on such regional code.

[0046] Next, the acquisition unit 35 acquires past performance information on the amount of power generation stored in the storage unit 32 (S12). The performance information is, for example, information in which the performance of the amount of power generation on a certain day in the past is associated with weather information indicating the actual weather on that day (weather, solar radiation information, humidity information, temperature information, etc.). The performance of the amount of power generation is measured, for example, by the solar power generation system 21, and the weather information is provided, for example, by the weather information management server 50. The weather information may include information other than the examples described above.

[0047] Next, the prediction unit 36 ​​predicts the amount of power generation on the target day based on the weather forecast information acquired in step S11 and the performance information acquired in step S12 (S13). For example, by referring to the performance information, the prediction unit 36 ​​can regard the amount of power generation on the day with weather conditions that are closest to the weather conditions on the target day as the predicted amount of power generation on the target day.

[0048] Next, the control unit 37 determines whether to execute discharge control based on the predicted power generation amount (S14). In other words, this determination is a determination as to whether the SOC of the storage battery system 22 at a predetermined time should be controlled to 40% (an example of a first value) or 10% (an example of a second value). This determination is made using, for example, a threshold value. The threshold value is appropriately determined empirically or experimentally.

[0049] If the predicted power generation amount is equal to or greater than the threshold value (power generation amount is high in S14), the control unit 37 performs discharge control (S15). In other words, the control unit 37 causes the load 24 to consume the power stored in the storage battery system 22. Specifically, the control unit 37 performs discharge control by transmitting a control signal to the storage battery system 22, instructing it to discharge, using the first communication unit 33. In the discharge control, the discharge of the storage battery system 22 is stopped when the SOC of the storage battery system 22 reaches 10%.

[0050] As a result, the SOC of the storage battery system 22, which was initially 40%, drops to 10% by the predetermined time. Note that the load 24 is not forcibly operated in order to lower the SOC of the storage battery system 22. The extent to which the SOC of the storage battery system 22 drops depends on how the user of the facility 60 operates the load 24. Therefore, the time interval between the determination timing and the predetermined time is appropriately determined empirically or experimentally so that the SOC can reach 10% by the predetermined time.

[0051] During discharge control, the SOC falls below the lower limit, resulting in a decrease in resilience. However, if the predetermined time is set to a time before or after sunrise, the SOC can be expected to recover quickly. In other words, if the predetermined time is set to a time before or after sunrise, the period during which resilience decreases can be shortened.

[0052] On the other hand, if the predicted power generation amount is less than the threshold (the power generation amount is low in S14), the control unit 37 does not execute the discharge control. As a result, the SOC of the storage battery system 22 remains at 40% and will be 40% at the predetermined time.

[0053] As described above, the power management system 10 performs discharge control when the predicted power generation amount, which is a predicted value of the amount of power generated by the photovoltaic power generation system 21 on a target day and is determined based on weather forecast information, is equal to or greater than a threshold. According to the discharge control, the SOC of the storage battery system 22 reaches a second value (e.g., 10%) that is smaller than the first value from a first value (e.g., 40%) by a predetermined time in the morning of the target day. On the other hand, when the predicted power generation amount is less than the threshold, the power management system 10 does not perform discharge control and maintains the SOC of the storage battery system 22 at the first value.

[0054] Such an electric power management system 10 can increase the amount of self-consumption while maintaining resilience.

[0055] In the first operational example, the amount of power generation is predicted based on the weather forecast information and the performance information, but the method for predicting the amount of power generation is not limited to this. For example, the amount of power generation may be predicted using a machine learning model constructed using the performance information as learning data. The prediction unit 36 ​​can obtain the predicted amount of power generation by inputting the weather forecast information acquired by the acquisition unit 35 into the machine learning model.

[0056] [Example 2] The determination of whether to execute discharge control may be made using predicted demand, which is a predicted value of the amount of power usage on a target day. A second example of such an operation of the power management system 10 will now be described. FIG. 4 is a flowchart of the second example of operation of the power management system 10.

[0057] The processing of steps S21 to S23 is the same as the processing of steps S11 to S13, and therefore detailed description thereof will be omitted. After step S23, the acquisition unit 35 acquires historical information on the amount of power consumption in the facility 60 (S24). As described above, the daily amount of power consumption of all of the loads 24 in the facility 60 measured by the power metering device 25 is stored as historical information in the storage unit 32. The acquisition unit 35 can acquire such historical information on the amount of power consumption from the storage unit 32.

[0058] Next, the prediction unit 36 ​​predicts the power consumption (power demand) of all the loads 24 in the facility 60 during the daytime of the target day based on the power consumption history information acquired in step S24 (S25). Daytime refers to the period from sunrise to sunset, for example.

[0059] For example, the prediction unit 36 ​​predicts the daytime power usage of the target day as the average value of daytime power usage in the most recent specified period. The prediction unit 36 ​​may further take into account the day of the week and predict the daytime power usage of the target day as the average value of daytime power usage on the same day of the week as the target day in the most recent specified period. The prediction unit 36 ​​may further take into account seasonality (such as summer or winter) when predicting the daytime power usage of the target day. Other existing algorithms may also be used to predict the power usage. Hereinafter, the predicted value of power usage will also be referred to as predicted demand.

[0060] Next, the control unit 37 determines whether to execute discharge control based on the predicted power generation amount (S26). In other words, this determination is a determination as to whether the SOC of the storage battery system 22 at a predetermined time should be controlled to 40% (an example of a first value) or 10% (an example of a second value). This determination is made using, for example, a threshold value.

[0061] If the predicted power generation amount is greater than or equal to the predicted demand (power generation amount≧demand in S26), the control unit 37 performs discharge control (S27). In other words, the control unit 37 causes the load 24 to consume the power stored in the storage battery system 22. Specifically, the control unit 37 performs discharge control by transmitting a control signal to the storage battery system 22 using the first communication unit 33 to instruct the storage battery system 22 to discharge. In the discharge control, the discharge of the storage battery system 22 is stopped when the SOC of the storage battery system 22 reaches 10%.

[0062] As a result, the SOC of storage battery system 22, which was initially 40%, drops to 10% by the predetermined time. The time interval between the determination timing and the predetermined time is appropriately determined empirically or experimentally so that the SOC can reach 10% by the predetermined time.

[0063] On the other hand, if the predicted power generation amount is less than the predicted demand (power generation amount<demand in S26), the control unit 37 does not execute discharge control. As a result, the SOC of the storage battery system 22 remains at 40% and is also 40% at the predetermined time.

[0064] As described above, the power management system 10 determines whether to perform discharge control based on the predicted power generation amount as well as the predicted demand, which is the predicted value of power usage on the target day determined based on the acquired historical information.

[0065] Such an electric power management system 10 can increase the amount of self-consumption while maintaining resilience.

[0066] [Decision timing decision operation] In the operation examples 1 and 2, the determination timing for determining whether or not to execute discharge control is a predetermined fixed timing, but the control unit 37 may adaptively (flexibly) determine the determination timing based on the predicted demand. Fig. 5 is a flowchart of the operation for determining the determination timing.

[0067] The acquisition unit 35 acquires historical information about the amount of power usage in the facility 60 (S31). As described above, the daily amount of power usage by all of the loads 24 in the facility 60 measured by the power metering device 25 is stored as historical information in the storage unit 32. The acquisition unit 35 can acquire such historical information about the amount of power usage from the storage unit 32.

[0068] Next, the prediction unit 36 ​​predicts the power consumption (power demand) of all the loads 24 in the facility 60 for a time period in the morning of the target day before the predetermined time, based on the power consumption history information acquired in step S31 (S32). This time period is, for example, the time period from midnight to sunrise on the target day. As a method for predicting the power consumption in step S32, the various methods described in operation example 2 can be used. Hereinafter, the predicted value of the power consumption will also be referred to as predicted demand.

[0069] Next, the control unit 37 estimates the time required to reduce the SOC of the storage battery system 22 from 40% to 10% during the time period based on the predicted demand (S33). The control unit 37 determines the timing that is the estimated time before the predetermined time as the determination timing (S34).

[0070] If the determination timing is determined in this way, the determination of whether to execute discharge control will be made as late as possible, taking into account the time required to discharge power equivalent to 30% SOC. This increases the likelihood of obtaining the latest weather forecast information, allowing the power management system 10 to improve the accuracy of power generation predictions.

[0071] The determination timing may be any timing that is earlier than the predetermined time by the time estimated in step S33. If the determination timing is determined in this manner, it is possible to prevent the SOC from failing to reach 10% at the predetermined time.

[0072] Furthermore, the power management system 10 may determine a time corresponding to the predetermined time based on the predicted demand and the predicted power generation amount, instead of the determination timing. The predetermined time in the above embodiment is ideally considered to be the timing when the predicted demand and the predicted power generation amount substantially match. This timing corresponds to the time ta when the power generation amount is regarded as the predicted power generation amount and the demand is regarded as the predicted demand in (a) of FIG. 2 above. Therefore, the control unit 37 may determine the timing when the predicted demand and the predicted power generation amount substantially match as the time corresponding to the predetermined time, based on the predicted demand and the predicted power generation amount.

[0073] [Variations] In the above embodiment, some or all of the processes described as being executed by the control device 30 may be executed by other devices. For example, some or all of the processes executed by the acquisition unit 35, the prediction unit 36, and the control unit 37 may be executed by a computer included in the storage battery system 22. In other words, the storage battery system 22 may include functional components corresponding to the acquisition unit 35, the prediction unit 36, and the control unit 37.

[0074] Similarly, some or all of the processes executed by the acquisition unit 35, the prediction unit 36, and the control unit 37 may be executed by a computer included in the power conditioner 23. In other words, the power conditioner 23 may include functional components corresponding to the acquisition unit 35, the prediction unit 36, and the control unit 37.

[0075] Furthermore, some or all of the processes executed by the acquisition unit 35, the prediction unit 36, and the control unit 37 may be executed by a computer included in the server device 40. In other words, the server device 40 may include functional components corresponding to the acquisition unit 35, the prediction unit 36, and the control unit 37.

[0076] Furthermore, if the power management system 10 does not include the server device 40, as described above, the discharge control may be realized by a combination of the control device 30, the computer included in the storage battery system 22, and the computer included in the power conditioner 23. In this case, information from the weather information management server 50 is received directly by the control device 30, and the control content is determined based on the information stored in the storage device 32 included in the control device 30.

[0077] [System configuration variations] The system configuration of the power management system 10 is not limited to the configuration shown in Fig. 1. For example, of the system configuration shown in Fig. 1, the components other than the control device 30 in the facility 60 may be configured as shown in Fig. 6 or 7, depending on the facility 60. Fig. 6 is a diagram showing a first variation of the system configuration, and Fig. 7 is a diagram showing a second variation of the system configuration.

[0078] 6, a solar power generation system 21, a storage battery system 22, a power conditioner 23, and a load 24 are connected to a distribution board 27, and electricity (power) is distributed. Information on the amount of power used by all of the devices 24 under the control of the distribution board 27, the amount of power generated, etc. is measured by a power measurement device 25 provided between the grid power supply 70 and the distribution board 38. Alternatively, the amount of power purchased from and sold by the grid power supply is measured by a smart meter 26. However, a power measurement device may be built into the solar power generation system 21, the storage battery system 22, or the power conditioner 23.

[0079] 7, power conditioner 23a, which converts the power obtained from solar power generation system 21, and power conditioner 23b, which is used to manage storage battery system 21, are separate entities. Power conditioner 23a, power conditioner 23b, and load 24 are connected in parallel to distribution board 38, so that power measurement device 25 can be installed at any position so that the amount of power generated or consumed by each device can be measured. Also in the example of FIG. 7, smart meter 26 may be additionally installed between system power supply 70 and distribution board 27 for the purpose of monitoring the amount of power generated and consumed by the entire facility 60.

[0080] [Effects, etc.] As described above, the power management system 10 includes an acquisition unit 35 that acquires weather forecast information, and a control unit 37 that determines whether to discharge the storage battery system 22 that stores the power generated by the solar power generation system 21 based on the predicted power generation amount, which is a predicted value of the amount of power generated by the solar power generation system 21 on a target day determined based on the acquired weather forecast information, and performs discharge control based on the determination result. By performing the discharge control, the control unit 37 causes the SOC of the storage battery system 22 to reach a second value smaller than the first value from a first value by a predetermined time in the morning of the target day.

[0081] Such a power management system 10 can increase the amount of power that can be stored in the storage battery system 22 when it is predicted that the amount of power generated by the solar power generation system 21 will be large. The power management system 10 can reduce consumption of power supplied from the grid power supply 70 and promote consumption of power generated by the solar power generation system 21.

[0082] Also, for example, the control unit 37 performs the above-mentioned discharge control when the predicted power generation amount is equal to or greater than a threshold, and maintains the SOC of the storage battery system 22 at the first value without performing the above-mentioned discharge control when the predicted power generation amount is less than the threshold.

[0083] Such a power management system 10 increases the amount of power that can be stored in the battery system 22 when it is predicted that the amount of power generated by the solar power generation system 21 will be high, and can store power in the battery system 22 in preparation for emergencies when it is predicted that the amount of power generated by the solar power generation system 21 will be low.

[0084] Furthermore, for example, the acquisition unit 35 further acquires history information of the amount of electricity usage in the facility 60 in which the solar power generation system 21 and the storage battery system 22 are installed. The control unit 37 performs discharge control based on the predicted demand, which is a predicted value of the amount of electricity usage on a target day determined based on the acquired history information, in addition to the predicted amount of electricity generation.

[0085] Such a power management system 10 can increase the amount of power that can be stored in the storage battery system 22 when it is predicted that the amount of power generated by the solar power generation system 21 will be greater than the predicted demand.

[0086] Furthermore, for example, the first value is a lower limit value of the SOC that is set as a precaution against emergencies.

[0087] Such a power management system 10 can increase the amount of power that can be stored in the storage battery system 22 by lowering the SOC below a lower limit value of the SOC that is set as a precaution against emergencies.

[0088] Such a power management system 10 can determine whether or not to execute the above-described discharge control.

[0089] Also, for example, the control unit 37 performs the determination during the late night hours.

[0090] Such a power management system 10 can determine whether or not to execute the discharge control during the late night hours.

[0091] Furthermore, for example, the acquisition unit 35 further acquires history information of the amount of electricity usage in the facility 60 in which the solar power generation system 21 and the storage battery system 22 are installed. The control unit 37 further determines the timing of making the determination based on a predicted demand, which is a predicted value of the amount of electricity usage on the target day, determined based on the acquired history information.

[0092] Such a power management system 10 can adaptively determine the timing of determining whether or not to execute discharge control based on the predicted demand.

[0093] Furthermore, for example, the control unit 37 estimates the time required for the SOC of the storage battery system 22 to reach the second value from the first value based on the predicted demand, and determines the timing for making the judgment to be the time that is the estimated time before the specified time.

[0094] Such a power management system 10 can increase the likelihood of obtaining the latest weather forecast information.

[0095] For example, the power management system 10 further includes a server device 40 that receives weather forecast information from the weather information management server 50. The acquisition unit 35 acquires the weather forecast information through the server device 40.

[0096] Such a power management system 10 can acquire weather forecast information through the server device 40.

[0097] For example, the power management system 10 further includes a solar power generation system 21 and a storage battery system 22.

[0098] Such a power management system 10 can be realized as a system including a solar power generation system 21 and a storage battery system 22.

[0099] Furthermore, the power management method executed by a computer such as the power management system 10 includes an acquisition step of acquiring weather forecast information, and a control step of determining whether or not to discharge the storage battery system 22 that stores the power generated by the solar power generation system 21 based on the predicted power generation amount, which is a predicted value of the amount of power generated by the solar power generation system on a target day determined based on the acquired weather forecast information, and performing discharge control based on the determination result. By performing the discharge control, the SOC of the storage battery system 22 reaches a second value smaller than the first value from a first value by a predetermined time in the morning of the target day.

[0100] Such a power management method can increase the amount of power that can be stored in the storage battery system 22 when it is predicted that the amount of power generated by the solar power generation system 21 will be large. The power management method can reduce consumption of power supplied from the grid power supply 70 and promote consumption of power generated by the solar power generation system 21.

[0101] (Other embodiments) Although the embodiments have been described above, the present invention is not limited to the above-described embodiments.

[0102] For example, in the above embodiment, the power management system is realized by multiple devices. In this case, the components of the power management system may be distributed among the multiple devices in any manner. Furthermore, the power management system may be realized by a single device, for example, as a single device corresponding to the control device in the above embodiment.

[0103] In the above-described embodiment, the processing performed by a specific processing unit may be performed by another processing unit. The order of multiple processing operations may be changed, or multiple processing operations may be performed in parallel.

[0104] In the above-described embodiments, each component may be realized by executing a software program suitable for that component, or by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0105] Furthermore, each component may be realized by hardware. For example, each component may be a circuit (or integrated circuit). These circuits may form a single circuit as a whole, or each may be a separate circuit. Furthermore, each of these circuits may be a general-purpose circuit or a dedicated circuit.

[0106] Furthermore, the general or specific aspects of the present invention may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a computer-readable recording medium such as a CD-ROM, or as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0107] For example, the present invention may be realized as a control device, a storage battery system, or a power conditioner according to the above-described embodiments. Furthermore, the present invention may be realized as a power management method executed by a computer, such as a power management system, or as a program for causing a computer to execute such a power management method. The present invention may also be realized as a computer-readable non-transitory recording medium on which such a program is recorded.

[0108] In addition, the present invention also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art would think of, or forms realized by arbitrarily combining the components and functions of each embodiment within the scope of the present invention. [Explanation of symbols]

[0109] 10 Power Management System 21 Solar power generation system 22 Battery storage system 35 Acquisition Department 36 Prediction Department 37 Control Unit 40 Server device 50 Weather information management server 60 facilities

Claims

1. an acquisition unit that acquires weather forecast information; a control unit that determines whether to discharge a storage battery system that stores power generated by the solar power generation system based on a predicted power generation amount that is a predicted value of the power generation amount by the solar power generation system on a target day, the predicted power generation amount being determined based on the acquired weather forecast information, and performs discharge control based on a result of the determination; The control unit causes an SOC (State of Charge) of the storage battery system to reach a second value smaller than the first value by a predetermined time in the morning of the target day by performing the discharge control. Power management system.

2. The control unit When the predicted power generation amount is equal to or greater than a threshold, the discharge control is performed. When the predicted power generation amount is less than the threshold value, the discharge control is not performed and the SOC of the storage battery system is maintained at the first value. The power management system of claim 1 .

3. The acquisition unit further acquires history information of power usage in a facility in which the solar power generation system and the storage battery system are installed, The control unit performs the discharge control based on a predicted demand, which is a predicted value of the amount of power consumption on the target day, determined based on the acquired history information in addition to the predicted amount of power generation. The power management system according to claim 1 or 2.

4. The first value is a lower limit value of the SOC that is set as a precaution against emergencies. The power management system according to any one of claims 1 to 3.

5. The control unit performs the determination during a late-night time period. The power management system according to any one of claims 1 to 4.

6. The acquisition unit further acquires history information of power usage in a facility in which the solar power generation system and the storage battery system are installed, The control unit further determines the timing of making the determination based on a predicted demand, which is a predicted value of the amount of power usage on the target day, determined based on the acquired history information. The power management system according to any one of claims 1 to 4.

7. the control unit estimates a time required for the SOC of the storage battery system to reach the second value from the first value based on the predicted demand; The timing prior to the predetermined time by the estimated time is determined as the timing for making the determination. The power management system of claim 6.

8. Further, a server device is provided which receives the weather forecast information from the weather information management server, The acquisition unit acquires the weather forecast information through the server device. The power management system according to any one of claims 1 to 7.

9. moreover, the solar power generation system; The storage battery system The power management system according to any one of claims 1 to 8.

10. 1. A computer-implemented power management method comprising: an acquisition step of acquiring weather forecast information; a control step of determining whether or not to discharge a storage battery system that stores power generated by the photovoltaic power generation system based on a predicted power generation amount that is a predicted value of the power generation amount by the photovoltaic power generation system on a target day, the predicted power generation amount being determined based on the acquired weather forecast information, and performing discharge control based on a result of the determination; By performing the discharge control, the SOC of the storage battery system reaches a second value smaller than the first value from a first value by a predetermined time in the morning of the target day. Power management methods.

11. A program for causing a computer to execute the power management method according to claim 10.

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