Power Control System

Abstract

This electric power control system (1) has: a plurality of base stations (20) that are a plurality of consumers and that include a communication device (70), which is a load, a rectifier (50), and a storage battery (60); and a control unit (2) that controls the rectifier (50) and the storage battery (60) among the plurality of consumers, wherein a power conservation operation among the plurality of consumers is performed on the basis of a power conservation request. The control unit (2) responds to the power conservation request by dividing a time slot for which the power conservation request is made into a plurality of unit times (intervals), selecting from the plurality of consumers a consumer to serve as a target for performing power conservation control on the basis of the amount of the power conservation request for each unit time, and performing a discharge operation from the storage battery (60) of the selected consumer.

Description

[Technical Field]

[0001] One aspect of the present disclosure relates to a power control system. [Background technology]

[0002] In recent years, as the proportion of renewable energy used by power suppliers has increased, demand response (DR) has attracted attention as a method for adjusting the supply and demand of electricity from power suppliers to consumers. Because the amount of electricity generated by renewable energy sources such as solar power generation and wind power generation fluctuates depending on the weather (such as the amount of solar radiation and wind volume), a method has been adopted to flexibly adjust the amount of electricity supply and demand by requesting DR from consumers, in which consumers are requested to save electricity by specifying the amount of power they want to save. In response to this, consumers have been considering power control methods for responding to DR. For example, Patent Document 1 discloses a method for allocating limited power allocations to multiple consumers while taking into account the amount of electricity stored in storage batteries owned by the multiple consumers when responding to DR. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-33273 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the power saving requests of consumers may change from moment to moment, and the power consumption of the consumer's load may also change, so it is expected that the situation where the power saving requests can be met may not continue for some consumers.

[0005] The present disclosure has been made in consideration of the above, and aims to provide a technology that can flexibly respond to requests for power saving while taking into account the power usage status of multiple consumers. [Means for solving the problem]

[0006] A power control system according to one aspect of the present disclosure has a plurality of consumers including loads, rectifiers, and storage batteries, and a control unit that controls the rectifiers and the storage batteries in the plurality of consumers, and performs power saving operations at the plurality of consumers based on a power saving request, wherein the control unit divides a time period during which the power saving request is made into a plurality of unit times, selects a consumer from the plurality of consumers that is to be subject to power saving control based on the amount of power saving request per unit time, and responds to the power saving request by performing a discharge operation from the storage battery in the selected consumer.

[0007] In this aspect, even if the power saving request amount varies depending on the time period, a consumer that is the target of power saving control is selected from multiple consumers based on the power saving request amount per unit time. Then, a discharge operation from the storage battery is performed at the selected consumer. Therefore, even if the power saving request amount varies, it is possible to flexibly respond to the power saving request. Furthermore, because a consumer that is the target of power saving control is selected from multiple consumers and a discharge operation from the storage battery is performed, it is possible to determine whether to perform a discharge operation depending on the situation of each consumer. [Effects of the Invention]

[0008] According to one aspect of the present disclosure, a technique is provided that can flexibly respond to requests for power saving while taking into account the power usage status of multiple consumers. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram illustrating an example of a schematic configuration of a power control system according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of the functional configuration of the control unit in the power control system according to the first embodiment. [Figure 3] FIG. 3 is a diagram illustrating an example of the relationship between the power saving request amount and the power saving amount. [Figure 4]FIG. 4 is a flowchart showing an example of a power control method according to the first embodiment. [Figure 5] FIG. 5 is a diagram illustrating an example of the functional configuration of a control unit in the power control system according to the second embodiment. [Figure 6] FIG. 6 is a flowchart showing an example of a power control method according to the second embodiment. [Figure 7] FIG. 7 is a diagram illustrating an example of a hardware configuration of a computer used in the power control system. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0011] (First embodiment) As shown in FIG. 1, a power control system 1 including the power control system according to the first embodiment includes a server 10 that controls a plurality of (n) base stations 20 (a first base station 201, a second base station 202, a third base station 203, ... an n-th base station 20) n 1, the configuration of the base station 20 will be described with reference to the first base station 201, but the other base stations also have similar configurations.

[0012] Each base station 20 includes a smart meter 30, a Home Energy Management System (hereinafter referred to as "HEMS") 40, a rectifier 50, a storage battery 60 for backing up the commercial power supply in case of a power outage, and a communication device 70 (hereinafter sometimes referred to as "load") that consumes direct current. AC current from a commercial power supply 90 is input to the rectifier 50 via the smart meter 30 and converted to direct current by the rectifier 50. The converted direct current is supplied to the communication device 70 and the storage battery 60. The HEMS 40 receives commercial power information from the smart meter 30, measured values ​​from sensors (e.g., a current measuring unit and a bus voltage measuring unit) that may be provided in the rectifier 50, and a state of charge (State Of Charge) from the storage battery 60. The HEMS 40 acquires information on the state of charge (hereinafter referred to as "SOC") of the storage battery 60. Examples of information from the sensor provided in the rectifier 50 include the value of the current flowing to the communication device 70 and the bus voltage value of the bus through which direct current is supplied to the communication device 70. The HEMS 40 also has a function of issuing a command to the rectifier 50 to set the rectifier voltage, causing the rectifier 50 to perform the desired operation. The command to set the rectifier voltage corresponds to a control command related to charging and discharging the storage battery 60.

[0013] In each base station 20, the HEMS 40 adjusts the current within the base station 20. The HEMS 40 notifies the server 10 of the power status within the base station 20 in which the HEMS 40 is installed, and adjusts each section within the base station 20 based on instructions from the server 10. In this way, the server 10 communicates with the HEMS 40 installed in each base station 20 to check the power operation status of each base station 20. In addition, based on a power saving request such as a demand response (DR) request to the power control system 1, the server 10 has a function of determining whether or not to respond to the power saving request at each base station 20 based on the power operation status at each base station 20, and based on the result of the determination, issuing a command to the HEMS 40 installed in each base station 20 to charge or discharge the storage battery in response to the power saving request.

[0014] In the above-described power control system 1, each base station 20 corresponds to a so-called consumer. The server 10 and the HEMS 40 function as a control unit 2 that controls the operation of power in a plurality of consumers.

[0015] Next, the functions of the server 10 and HEMS 40 that function as the control unit 2 will be described with reference to Fig. 2. Note that Fig. 2 shows the functions of the control unit 2 collectively, but as described above, the functions of the control unit 2 are distributed and allocated to the server 10 and the HEMS 40.

[0016] The control unit 2 includes a DR communication unit 11, a discharge power detection unit 12, a storage battery capacity detection unit 13, a memory unit 14, a duration calculation unit 15, an interval comparison unit 16, a base station selection unit 17, a discharge determination unit 18, and a storage battery capacity update unit 19. These functions are basically provided in the server 10, and some of the functions may be distributed to the HEMS 40.

[0017] Before explaining each part of the control unit 2, we will explain the "interval" used in the power control system 1 of this embodiment with reference to Figure 3, and also explain the control content by the server 10 and HEMS 40 that function as the control unit 2.

[0018] The power control system 1 adjusts the total amount of power saved by all base stations 20 based on the power saving request. In Fig. 3, the power saving request amount A for the power control system 1 is shown by a curve. As shown in Fig. 3, the power control system 1 according to this embodiment assumes that the power saving request amount changes over time, and sets a unit time called an interval to perform management for each unit time. In the example shown in Fig. 3, the time period from time t=0 to T when a power saving request is made is divided into a plurality of intervals (for example, n intervals), and the interval times are designated as time t k (k=0 to n). In this case, time t=0 is set as time t0, and time T is set as time t n In addition, the time period of each section is set as interval Δt k (k=0~n-1). Interval Δt k is t=t k~t k+1 The interval Δt k The time span can be several minutes to several hours. k The length of the period does not have to be constant, and may be set appropriately according to fluctuations in the power saving request amount A, for example.

[0019] Each interval Δt k In this case, the total amount of power saving by all base stations 20 is set as the maximum value of the power saving request amount A in the relevant interval. For example, in one interval Δt k In this case, the power saving requirement A is gradually decreasing, so in the interval Δt k Initial power saving requirement A for the period k The amount of power saved during this period is set so that the amount of power saved corresponds to the interval Δt k A base station 20 that responds to the power saving request is selected from all base stations on a per-base-station basis. Specifically, a base station 20 that can respond to the power saving request is selected based on the amount of power stored in the storage battery 60 at each base station 20 and the amount of power used by the load (communication device 70) at each base station 20. In this way, in the power control system 1, when the amount of power saved in the power saving request fluctuates, control is performed so that the power saving request is responded to appropriately and the amount of power stored in the storage battery 60 does not decrease excessively.

[0020] Returning to Fig. 2, the following describes each unit constituting the control unit 2. The DR communication unit 11 is a device of a power supply company or the like, and has a function of communicating with an external device that issues a DR command to the power control system 1. Specifically, the DR communication unit 11 has a function of receiving a DR command from the power supply company or the like, and also transmits to the power supply company or the like route B data of the smart meter required for reporting the performance of DR.

[0021] The discharge power detection unit 12 has a function of acquiring the output power from the rectifier 50. The discharge power detection unit 12 may be realized as a function of the HEMS 40, for example.

[0022] The battery capacity detection unit 13 has a function of acquiring the current battery capacity from the storage battery 60. The battery capacity detection unit 13 may be realized as a function of the HEMS 40, for example.

[0023] The storage unit 14 has a function of storing information related to the backup capacity of the storage battery for disasters that should be secured by each base station 20. The storage unit 14 may be provided in the HEMS 40 of each base station 20, or the server 10 may hold information on all base stations 20 under its management.

[0024] The duration calculation unit 15 has a function of calculating, based on a specific time, the duration of continuous discharge from the storage battery 60 of each base station 20. The detailed procedure will be described later, but the calculation result by the duration calculation unit 15 is used to determine whether power saving control is possible in the base station 20.

[0025] The interval comparison unit 16 has a function of comparing the time during which the discharged state can be sustained, which is the result of calculation by the duration calculation unit 15, with the unit time (interval) for which power-saving control is required. If the time during which the discharged state can be sustained is longer than the interval, it means that the base station 20 having the storage battery 60 in question is capable of performing control in response to a power-saving request for the interval.

[0026] The base station selector 17 has a function of selecting, based on the comparison result by the interval comparator 16, a group of base stations that can participate in control in response to the power saving request from the base stations 20 under its control.

[0027] The discharge decision unit 18 has the function of deciding to discharge from the storage battery 60 for the base station 20 that performs control in response to the power saving request for the base station group selected by the base station selection unit 17, and executing specific control to respond to the power saving request.

[0028] The storage battery capacity update unit 19 has a function of updating the storage battery capacity information of the storage battery 60 of the base station 20 participating in the power-saving control by the amount of discharge expected during the time period (interval) during which the base station 20 participated. This processing by the storage battery capacity update unit 19 is not necessary when repeatedly acquiring storage battery capacity information from the storage battery 60 and selecting a base station 20 that responds to a power-saving request for only one interval. However, there are cases where base stations for responding to power-saving requests for multiple consecutive intervals are selected at once. In such cases, by performing processing by the above-mentioned units while updating the storage battery capacity information of the storage battery 60 in the storage battery capacity update unit 19, it is possible to estimate the capacity of the storage battery 60 in the future (after a predetermined interval has elapsed), and by using this estimation result, it is possible to appropriately select a base station 20 that responds to power-saving control.

[0029] Next, a specific procedure (power control method) of the process performed by the control unit 2 will be described with reference to FIG.

[0030] First, in step S01, the DR communication unit 11 receives a DR command from an electric power supply company or the like. Here, it is assumed that the DR request includes three levels of power saving requests over three periods. Specifically, it is assumed that the power saving requests are for period Δt0: 10 kW, period Δt1: 20 kW, and period Δt2: 15 kW. When the DR communication unit 11 receives the DR request, it notifies the discharge power detection unit 12 and the storage battery capacity detection unit 13, and the following steps S02 and S03 are performed.

[0031] First, in step S02, the discharge power detection unit 12 detects the first base station 20 l Output power P from rectifier 50 at (l=1, 2, 3, ..., n) l On the other hand, in step S03, the battery capacity detection unit 13 acquires the first base station 20 l From the storage battery 60, the current capacity W 0,l Get.

[0032] Next, in step S04, the duration calculation unit 15 calculates from the storage unit 14 the backup capacity W' of the storage battery 60 that the base station should secure. l This backup capacity is set in consideration of emergencies and the like. The duration calculation unit 15 calculates the output power P l , current capacity of storage battery 60 W 0,l , the backup capacity W′ of the storage battery 60 acquired from the memory unit 14 l Using the above, the duration T' at time k = 0 0,l The duration is calculated by the current output power P l is supplied to the communication device 70 from the storage battery 60, the time required for the capacity of the storage battery 60 to reach the backup capacity. k,l can be calculated by the following formula: T' k,l =(W k,l -W' l ) / P l When k=0, the following occurs: T' 0,l =(W 0,l -W' l ) / P l

[0033] Next, in step S05, the interval comparison unit 16 compares the duration T' 0,l Determine whether the duration T' exceeds the interval Δt0. 0,l exceeds the interval Δt0, that is, if discharge is possible for a time longer than the interval Δt0 (S05-YES), the first base station 20 l is regarded as a base station that can participate in power saving control in the interval Δt0. On the other hand, duration T' 0,l If the interval Δt is equal to or shorter than the interval Δt (S05-NO), the first base station 20 lis determined to be a base station that cannot participate in the power saving control in the interval Δt0. In this case, since it is treated as a base station that does not participate in the power saving control, it is not selected as a base station to be discharged, and therefore it is not included in the base station candidates to be selected in the subsequent step S06.

[0034] By performing the above procedure for each base station 20, all base stations 20 (201 to 20 N ) is used to determine whether or not to participate in the power saving control in the interval Δt0.

[0035] Next, in step S06, the base station selector 17 selects, from the group of base stations that can participate in the control, a base station 20 that will discharge power so as to exceed the DR request amount of 10 kW in the interval Δt0. When the total power saving possible amount of the group of base stations 20 that can perform power saving control exceeds 10 kW, the base station selector 17 may select a base station 20 to perform control so that the total power saving amount is as close as possible to the power saving request amount of 10 kW. Also, a configuration may be adopted in which power saving is performed preferentially on a base station 20 with a larger current capacity of the storage battery 60. Also, as a method for selecting an appropriate base station 20, an integer programming problem may be set and solved; specifically, a base station 20 may be selected by solving a knapsack problem. In this way, the method for selecting a base station by the base station selector 17 can be set as appropriate.

[0036] Here, in step S07, the storage battery capacity update unit 19 checks whether there is a next interval (an interval in which power saving control is required exists). At this time, if there is a next interval (an interval in which power saving control is required exists) (step S07-YES), in step S08, the storage battery capacity update unit 19 determines whether the base station 20 is selected as a control target, since subsequent processing changes depending on whether the base station 20 selected as a control target among the base stations 20 that are determined to be dischargeable is actually selected as a control target. First, for the base station 20 that is selected to participate in the power saving control in the interval Δt0 (S08-YES), in step S09, the storage battery capacity is updated by the amount of discharge expected in the interval Δt0 (Δt0×Pl ) is subtracted from W0 and updated as the storage battery capacity W1 expected at time t1. W k+1,l =W k,l -Δt k ×P l The calculation is performed, and when k=0, the result is as follows. W 1,l =W 0,l -Δt0×P l

[0037] On the other hand, the storage battery capacity of the base station 20 that is determined not to participate in the power saving control in the interval Δt0 (S08-NO) is set as W k+1,l =W k,l , where W 1,l =W 0,l The previous value is assumed to be inherited.

[0038] Thereafter, k=1 is set, and the base station 20 that will participate in the power saving control in the interval Δt1 is selected. Specifically, the duration calculation unit 15 calculates the duration T' at time k=1. 1,l is calculated (S04), and the interval comparison unit 16 compares the duration T' 1,l It is determined whether or not the DR request amount of 20 kW in the interval Δt1 is exceeded (S05). After the base stations 20 that can participate in the power saving control in the interval Δt1 are selected, the base station selector 17 selects, from the group of base stations 20 that can participate in the control, a base station 20 that will discharge so as to exceed the DR request amount of 20 kW in the interval Δt1 (S06).

[0039] Then, if there is a next interval (if there is an interval that requires power saving control) (step S07-YES), the storage battery capacity update unit 19 updates the storage battery capacity of the base station 20 that is determined to participate in the power saving control by the estimated discharge amount in the interval Δt1 (Δt1×P l) from W1 and updates the value as the storage battery capacity W2 expected at time t2 (S08 to S10). Based on this result, a series of processes are further performed to select a group of base stations to discharge so that the requested amount in the interval Δt2 exceeds 15 kW. As a result, the base stations 20 that will perform power saving control to respond to the DR request in the three intervals are selected. In this way, by repeating the above steps S04 to S10 according to the number of intervals (intervals) in which power saving control is performed, it is possible to select the base station 20 that will perform power saving control for each interval in which power saving control is performed, and a discharge plan for the storage battery 60 to respond to the DR request is created.

[0040] By the above procedure, the base station 20 that will participate in the power saving control (discharge control of the storage battery 60) is selected for each interval. When the discharge plan for the base station 20 at the DR activation time is created in this way, it is determined in step S07 that the next interval does not exist (there is no interval that requires power saving control) (step S07-NO), and the process for selecting the base station to be the power saving target is terminated. Then, in step S11, a discharge command is transmitted from the discharge determination unit 18 to each base station 20. At a predetermined time, each base station 20 performs a discharge operation from the storage battery 60. Regarding the discharge from the storage battery 60, as shown in step S11, the rectifier voltage V RF (Example: 45V) to the battery voltage V LIB This is done by setting the voltage lower than the reference voltage (e.g., 48V). By performing a discharge operation for the selected base station 20 at each interval based on the discharge plan, a power saving operation is performed for the entire power control system 1 to respond to the DR request.

[0041] (Second embodiment) Next, a power control system according to a second embodiment will be described.

[0042] The power control system 1 according to the first embodiment is designed to perform power saving operations based on a DR request. On the other hand, in the second embodiment, the power control system 1 predicts the power demand at a plurality of base stations 20 that are distributed, thereby making it possible to reduce the peak power demand at all base stations 20. That is, it is designed to predict power demand, and to cover any power exceeding a predetermined amount with power stored in the storage battery 60 at the base station 20, rather than purchasing it from a commercial power source 90. This configuration makes it possible to suppress the purchase of power exceeding a predetermined amount. However, since the predicted power demand may not match the actual power usage, a feature unique to the second embodiment is that a backup base station (buffer station) that performs power saving control is set up.

[0043] To realize the above configuration, the functions of the server 10 and the control unit 2 of the HEMS 40 are partially different.

[0044] The functions of the server 10 and the HEMS 40 that function as the control unit 2A in the power control system 1 according to the second embodiment will be described with reference to Fig. 5. Note that in Fig. 5, the functions of the control unit 2A are shown collectively, but as described above, the functions of the control unit 2A are distributed across the server 10 and the HEMS 40.

[0045] The control unit 2A includes a power saving amount prediction unit 81, a discharge power detection unit 82, a storage battery capacity detection unit 83, a memory unit 84, a duration calculation unit 85, an interval comparison unit 86, a base station selection unit 87, a discharge determination unit 88, and a storage battery capacity update unit 89. The control unit 2A further includes a control amount measurement unit 91, a buffer station management unit 92, and a correction unit 93. The functions of the discharge power detection unit 82, the storage battery capacity detection unit 83, the memory unit 84, the duration calculation unit 85, the interval comparison unit 86, the base station selection unit 87, the discharge determination unit 88, and the storage battery capacity update unit 89 are basically the same as the discharge power detection unit 12, the storage battery capacity detection unit 13, the memory unit 14, the duration calculation unit 15, the interval comparison unit 16, the base station selection unit 17, the discharge determination unit 18, and the storage battery capacity update unit 19 in the control unit of the first embodiment, and therefore will only be briefly described.

[0046] The power saving amount prediction unit 81 predicts the power demand of each base station 20 by means of regression analysis using predicted data on ambient temperature and actual values ​​of past power demand, and derives a predicted value for the overall power demand. As a result, power exceeding a predetermined threshold B is regarded as the amount of power saving to be achieved. This makes it possible to contribute to reducing local demand peaks without the amount of power purchased by the entire base stations exceeding threshold B. The power saving amount prediction unit 81 calculates the amount of power saving at each interval. This is the same as in the first embodiment.

[0047] The discharge power detection unit 82 has a function of acquiring output power from the rectifier 50. The storage battery capacity detection unit 83 has a function of acquiring the current storage battery capacity from the storage battery 60. The memory unit 84 has a function of storing information related to the backup capacity of the storage battery for disasters that each base station 20 should secure.

[0048] The duration calculation unit 85 has a function of calculating the duration when the discharge from the storage battery 60 of each base station 20 is continued, with a specific time as a reference.

[0049] The interval comparison unit 86 has a function of comparing the time during which the discharged state can be sustained, which is the result of calculation by the duration calculation unit 85, with the unit time (interval) for which power-saving control is required. If the time during which the discharged state can be sustained is longer than the interval, it means that the base station 20 having the storage battery 60 in question is capable of power-saving control for the interval.

[0050] The base station selection unit 87 has a function of selecting a group of base stations that can participate in control corresponding to the power saving request from the base stations 20 under its control, based on the comparison result by the interval comparison unit 86 .

[0051] The discharge decision unit 88 has a function of executing control to instruct the base station 20 that performs control in response to the power saving request to discharge from the storage battery 60 for the base station group selected by the base station selection unit 87 .

[0052] The storage battery capacity update unit 89 has a function of updating the information on the storage battery capacity of the storage battery 60 of the base station 20 that has participated in the power saving control by the amount of discharge expected during the time period (interval) in which the base station 20 has participated.

[0053] The control amount measurement unit 91 has a function of monitoring the discharge control by the discharge determination unit 88 and monitoring whether the total discharge power at a specific time is below the required amount of power saving derived from the demand forecast, i.e., the amount of power saving assumed at the time of forecasting. Furthermore, when the control amount measurement unit 91 detects that the total discharge power at a specific time is below the required amount of power saving derived from the demand forecast, it identifies the difference as the control amount.

[0054] The buffer station management unit 92 has a function of selecting, by the base station selection unit 87, a base station 20 that will discharge from the storage battery 60 at each interval, and then selecting and managing, as a buffer station, a base station 20 that includes a storage battery 60 that has a capacity that allows for discharge separate from the discharge based on the discharge plan.

[0055] The correction unit 93 has a function of performing discharge control by the control amount specified by the control amount measurement unit 91 using the storage battery 60 included in the buffer station selected by the buffer station management unit 92 .

[0056] Next, a specific procedure of the process performed by the control unit 2A will be described with reference to FIG.

[0057] First, in step S21, the power saving amount prediction unit 81 predicts the amount of power saving as described above. As in the first embodiment, different amounts of power saving can be set for multiple periods (for example, intervals Δt0 to Δt3). When the power saving amount prediction unit 81 calculates the amount of power saving for each period (interval), it notifies the discharge power detection unit 82 and the storage battery capacity detection unit 83, and the processes of the following steps S22 and S23 are performed.

[0058] First, in step S22, the discharge power detection unit 82 detects the first base station 20 lOutput power P from rectifier 50 at (l=1, 2, 3, ..., n) l On the other hand, in step S23, the storage battery capacity detection unit 83 acquires the value of the first base station 20 l From the storage battery 60, the current capacity W 0,l Get.

[0059] Next, in step S24, the duration calculation unit 85 calculates from the storage unit 84 the backup capacity W' of the storage battery 60 that the base station should secure. l This backup capacity is set in consideration of emergencies and the like. The duration calculation unit 85 calculates the output power P l , current capacity of storage battery 60 W 0,l , the backup capacity W′ of the storage battery 60 acquired from the memory unit 84 l Using the above, the duration T' at time k = 0 0,l As in the first embodiment, the duration T' is calculated. k,l can be calculated by the following formula: T' k,l =(W k,l -W' l ) / P l

[0060] Next, in step S25, the interval comparison unit 86 compares the duration T' 0,l Determine whether the duration T' exceeds the interval Δt0. 0,l exceeds the interval Δt0, that is, if discharge is possible for a time longer than the interval Δt0 (S25-YES), the first base station 20 l is regarded as a base station that can participate in power saving control in the interval Δt0. On the other hand, duration T' 0,l If the interval Δt is equal to or shorter than the interval Δt (S25-NO), the first base station 20 lis determined to be a base station that cannot participate in the power saving control in the interval Δt0. In this case, since it is treated as a base station that does not participate in the power saving control, it is not selected as a base station to be discharged, and therefore it is not included in the base station candidates to be selected in the subsequent step S26.

[0061] By performing the above procedure for each base station 20, all base stations 20 (201 to 20 n ) is used to determine whether or not to participate in the power saving control in the interval Δt0.

[0062] Next, in step S26, the base station selector 87 selects a base station 20 that will discharge power so as to exceed the amount of power saved in the interval Δt0 from the group of base stations that can participate in the control. The method for selecting a base station by the base station selector 87 can be set appropriately, as in the first embodiment.

[0063] Here, in step S27, the storage battery capacity update unit 89 checks whether there is a next interval (an interval in which power saving control is required exists). At this time, if there is a next interval (an interval in which power saving control is required exists) (step S27-YES), in step S28, the storage battery capacity update unit 89 determines whether the base station 20 is selected as a control target, since subsequent processing changes depending on whether the base station 20 selected as a control target among the base stations 20 that are allowed to discharge is actually selected as a control target. First, for a base station 20 that has been selected to participate in power saving control in interval Δt0 (S28-YES), in step S29, the storage battery capacity is updated by the amount of discharge expected in interval Δt0 (Δt0×P l ) is subtracted from W0 and updated as the storage battery capacity W1 assumed at time t1. W k+1,l =W k,l -Δt k ×P l The calculation is performed along the

[0064] On the other hand, the storage battery capacity of the base station 20 that is determined not to participate in the power saving control in the interval Δt0 (S28-NO) is set as W k+1,l =W k,l , where W 1,l =W 0,l The previous value is assumed to be inherited.

[0065] Thereafter, k=1 is set, and the base stations 20 that will participate in the power saving control in the interval Δt1 are selected. The specific procedure is the same as above. As in the first embodiment, by repeating the above steps S24 to S30 depending on the number of intervals (intervals) in which the power saving control is performed, it is possible to select the base station 20 that will be the target of the power saving control for each interval in which the power saving control is performed, and a discharge plan for the storage battery 60 that will achieve the desired amount of power saving is created.

[0066] Once the discharge plan for each base station 20 has been made, it is determined in step S27 that the next interval does not exist (there is no interval requiring power saving control) (step S27-NO), and therefore the process of selecting the base station to be power-saved is terminated.

[0067] Here, in step S31, the buffer station management unit 92 selects a buffer station. Specifically, based on the result of the duration calculation by the duration calculation unit 85, the result of the comparison with the interval by the interval comparison unit 86, and the result of the selection of the base station to be controlled by the base station selection unit 87, the base station 20 having the storage battery 60 whose remaining capacity is greater than the backup capacity even after the discharge plan is created is selected as the buffer station. Multiple buffer stations may be selected. The base station 20 selected as the buffer station will perform normal operation until control related to the correction described below is performed.

[0068] Next, in step S32, the discharge decision unit 38 transmits a discharge command to each base station 20. At a predetermined time, each base station 20 performs a discharge operation from the storage battery 60. Regarding the discharge from the storage battery 60, as shown in step S11, the rectifier voltage VRF (Example: 45V) to the battery voltage V LIB This is done by setting it lower (e.g. 48V).

[0069] During the discharging operation, the control amount measuring unit 91 monitors whether the discharging operation is being performed properly. That is, in step S33, the control amount measuring unit 91 monitors whether the discharging operation is being performed properly at time t k The control variable x is the sum of the discharge power in k and time t k Power saving (discharge) demand A k The difference between and is confirmed. Here, at time t k The control variable x is the sum of the discharge power in k At time t k Power saving demand A k If it is confirmed that the power saving request amount A is less than the power saving request amount A (S33-NO), the correction unit 93 performs a correction operation in step S34. That is, the correction unit 93 acquires information on the buffer stations managed by the buffer station management unit 92. Then, the correction unit 93 notifies the buffer station of the power saving request amount A k A buffer station is selected from the group of buffer stations so as to satisfy the above condition, and discharge is performed. This allows control so that the amount of power discharged corresponds to the desired amount of power discharge. k The control variable x is the sum of the discharge power in k At time t k Power saving demand A k If the discharge time becomes equal to or exceeds the discharge time (YES in S33), the corrector 93 ends the discharge control of the buffer station and performs the discharge operation based on the discharge plan.

[0070] (action) The power control system 1 described above has a plurality of base stations 20 which are a plurality of consumers including a communication device 70 as a load, a rectifier 50, and a storage battery 60, and a control unit 2 (or control unit 2A) which controls the rectifiers 50 and the storage batteries 60 in the plurality of consumers, and performs power saving operations at the plurality of consumers based on a power saving request. Here, the control unit 2 divides the time period during which a power saving request is made into a plurality of unit times (intervals), selects a consumer from the plurality of consumers for which power saving control is to be performed based on the power saving request amount per unit time, and responds to the power saving request by discharging the storage battery 60 in the selected consumer.

[0071] With the above configuration, even if the power saving request amount varies depending on the time period, a consumer that is the target of power saving control is selected from multiple consumers based on the power saving request amount per unit time, i.e., per interval. Then, a discharge operation from the storage battery 60 is performed for the selected consumer. Therefore, even if the power saving request amount varies, it is possible to flexibly respond to the request. Furthermore, because a consumer that is the target of power saving control is selected from multiple consumers and a discharge operation from the storage battery is performed, it is possible to determine whether to perform a discharge operation depending on the situation of each consumer.

[0072] The control units 2, 2A may acquire output power information of the rectifier 50 and current capacity information of the storage battery 60 for each of a plurality of consumers, and select a consumer for which power-saving control is to be performed based on this information. Since power-saving control requires discharging the storage battery 60, the current capacity information of the storage battery 60 can be used to select a consumer taking into account the current capacity of the storage battery 60. Furthermore, the output power information of the rectifier 50 can be used to determine how much power can be saved if the consumer (base station 20) is selected as a target for power-saving control. In this way, by using the output power information of the rectifier 50 and the current capacity information of the storage battery 60, it is possible to more appropriately determine the status of each consumer when selecting a consumer, and appropriately select a consumer for which power-saving control is to be performed.

[0073] The control units 2, 2A may select a consumer for which power saving control is to be performed after ensuring the backup capacity of the storage battery 60 in each of the multiple consumers. In this case, by performing power saving control, the capacity of the storage battery 60 is prevented from falling below the backup capacity, and power saving control becomes possible while ensuring the backup capacity.

[0074] The control units 2, 2A may compare the control amount related to power saving for the entire plurality of consumers with the power saving request amount, and if the control amount is insufficient for the power saving request amount, perform a discharge operation from the storage battery 60 of a consumer other than the consumer that responded to the power saving request. It is assumed that the power saving amount corresponding to the power saving request amount cannot be achieved even if the power saving operation is performed as scheduled due to the operating conditions of each part in the consumer (for example, fluctuations in power usage in the communication device 70 as a load). In this case, the power saving amount can be increased by discharging the storage battery 60 of the consumer other than the consumer that responded to the power saving request as described above, thereby making it possible to achieve the power saving request amount. Therefore, the power saving operation based on the power saving request can be performed more appropriately.

[0075] The control units 2 and 2A may store in advance information about consumers who are different from the consumers who respond to the power-saving request and who are capable of discharging from their storage batteries. As an example, like the control unit 2A described above, information about buffer stations may be stored in advance. Then, when the control amount is insufficient for the power-saving request amount, a consumer who will discharge from the storage battery 60 may be selected based on the information. When information about consumers who are different from the consumers who respond to the power-saving request and who are capable of discharging from their storage batteries is stored, as in the buffer station described in the above embodiment, when selecting a consumer who will discharge to achieve the power-saving amount corresponding to the power-saving request amount, it is possible to prevent erroneous selection of a consumer who is inappropriate for discharging, such as a consumer with a low current capacity of the storage battery 60. This makes it possible to execute a power-saving operation based on the power-saving request while stabilizing the power usage state of each consumer.

[0076] As described in the first embodiment, the requested amount of power saving may be the amount of power saving required to respond to a demand response request. By performing the above control when responding to a demand response request, it becomes possible to respond to the demand response request appropriately while taking into account the power situation at each consumer.

[0077] Furthermore, as explained in the second embodiment, the power saving request amount may be a request to reduce a demand peak based on a power demand forecast. If the power demand peak is increased, there is a possibility that the amount of power purchased by the entire power control system 1 will increase. In response to this, by performing the above control to reduce the demand peak as described above, it is possible to suppress the demand peak while taking into account the power situation at each consumer.

[0078] The configuration of selecting a buffer station and performing correction using the buffer station may also be applied, for example, when responding to a demand response request described in the first embodiment.

[0079] The power control system 1 also relates to a technical field of DC power control technology for wireless base stations.

[0080] As another aspect of the above-described power control system 1 and power control method, there is a distributed power supply system (including a rectifier and a storage battery) and a power control method, respectively, as shown below.

[0081] [Item 1] A distributed power supply system or power control method comprising: a distributed power supply system equipped with a rectifier and a storage battery; a control unit that monitors and controls the rectifier and the storage battery for each base station; and power saving control that selects a base station to participate in the control in response to an increase or decrease in the amount of power saving required.

[0082] [Item 2] A distributed power supply system or power control method according to item 1, characterized in that the discharge amount of the storage battery is adjusted by adjusting the output voltage of the rectifier.

[0083] [Item 3] A distributed power supply system or power control method according to item 1, characterized in that backup capacity is secured in the event of a disaster by calculating the amount of power saved for each base station from rectifier information and storage battery information.

[0084] [Item 4] A distributed power supply system or power control method according to item 1, characterized in that during control, the control amount of the entire base station is compared with the amount of power saved, and if there is a shortage, the system corrects by discharging additional power from base stations that are not scheduled to participate in the power saving.

[0085] [Item 5] A distributed power supply system or power control method comprising: a distributed power supply system equipped with a rectifier and a storage battery; a control unit that monitors and controls the rectifier and the storage battery for each base station; and a distributed power supply system or power control method that responds to demand response by selecting a base station so as to satisfy the requested amount for each interval.

[0086] [Item 6] Item 5. A distributed power supply system or power control method, characterized in that the discharge amount of the storage battery is adjusted by adjusting the output voltage of the rectifier.

[0087] [Item 7] Item 5. A distributed power supply system or power control method characterized in that backup capacity is secured in the event of a disaster by calculating the amount of response possible to demand response for each base station from rectifier information and storage battery information.

[0088] [Item 8] Item 5. A distributed power supply system or power control method according to item 5, characterized in that, during the time when demand response is activated, the control amount of the entire base station is compared with the requested amount, and if there is a shortage, base stations that are not scheduled to participate in demand response are additionally discharged.

[0089] (others) The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0090] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, regard, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0091] For example, a power control system 1 according to an embodiment of the present disclosure may function as a computer that performs processing of the power control method of the present disclosure. Fig. 7 is a diagram illustrating an example of the hardware configuration of the power control system 1 according to an embodiment of the present disclosure. The above-described power control system 1 may be physically configured as a computer device including a processor C1, a memory C2, a storage C3, a communication device C4, an input device C5, an output device C6, a bus C7, etc.

[0092] In the following description, the term "device" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the control unit 2, 2A (server 10, HEMS 40) may be configured to include one or more of the devices shown in Fig. 7, or may be configured to exclude some of the devices.

[0093] Each function in the control unit 2, 2A (server 10, HEMS 40) is realized by loading specified software (programs) onto hardware such as processor C1 and memory C2, causing processor C1 to perform calculations, control communication via communication device C4, and control at least one of reading and writing data in memory C2 and storage C3.

[0094] The processor C1 controls the entire computer by running, for example, an operating system. The processor C1 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. For example, each unit included in the above-mentioned control units 2 and 2A may be realized by the processor C1.

[0095] The processor C1 also reads programs (program codes), software modules, data, etc. from at least one of the storage C3 and the communication device C4 into the memory C2 and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, each unit included in the control units 2 and 2A described above may be implemented by a control program stored in the memory C2 and running on the processor C1. While the above-described various processes have been described as being executed by one processor C1, they may also be executed simultaneously or sequentially by two or more processors C1. The processor C1 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0096] The memory C2 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory C2 may also be called a register, a cache, a main memory (primary storage device), etc. The memory C2 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0097] Storage C3 is a computer-readable recording medium, and may be composed of at least one of, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage C3 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of memory C2 and storage C3.

[0098] The communication device C4 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, or a communication module. The communication device C4 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc. to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). For example, each unit included in the above-mentioned control units 2 and 2A may be realized by the communication device C4. Furthermore, for example, the DR communication unit 11 may be implemented such that the receiving function and the transmitting function are physically or logically separated.

[0099] The input device C5 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device C6 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device C5 and the output device C6 may be integrated into one device (for example, a touch panel).

[0100] The processor C1, memory C2, and other devices are connected by a bus C7 for communicating information. The bus C7 may be configured using a single bus, or may be configured using different buses for each device.

[0101] Furthermore, the above-mentioned control units 2 and 2A may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor C1 may be implemented using at least one of these pieces of hardware.

[0102] Notification of information is not limited to the aspects / embodiments described in this disclosure, and may be performed using other methods.

[0103] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0104] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0105] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0106] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched depending on the implementation. Furthermore, notification of predetermined information (e.g., notification that "X is true") is not limited to being done explicitly, but may be done implicitly (e.g., by not notifying the predetermined information).

[0107] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0108] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0109] Software, instructions, information, etc. may also be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then these wired and / or wireless technologies are included within the definition of transmission media.

[0110] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0111] In addition, terms explained in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings.

[0112] As used in this disclosure, the terms "system" and "network" are used interchangeably.

[0113] Furthermore, the information, parameters, etc. described in the present disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0114] The names used for the parameters described above are not intended to be limiting in any way. Furthermore, the mathematical formulas and the like that use these parameters may differ from those explicitly disclosed in this disclosure. The various information elements may be identified by any suitable names, and the various names assigned to these various information elements are not intended to be limiting in any way.

[0115] In this disclosure, terms such as "base station (BS)," "radio base station," "fixed station," "NodeB," "eNodeB (eNB)," "gNodeB (gNB)," "access point," "transmission point," "reception point," "transmission / reception point," "cell," "sector," "cell group," "carrier," and "component carrier" may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, and picocell.

[0116] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, searching, inquiring (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in memory), and the like. Furthermore, "judgment" and "decision" can include regarding resolving, selecting, choosing, establishing, comparing, etc. as having been "judged" or "decided." In other words, "judgment" and "decision" can include regarding some action as having been "judged" or "decided." Furthermore, "judgment (decision)" can be interpreted as "assuming," "expecting," "considering," etc.

[0117] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using one or more wires, cables, and / or printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0118] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0119] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0120] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.

[0121] When used in this disclosure, the terms "include," "including," and variations thereof are intended to be inclusive, similar to the term "comprising." Furthermore, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0122] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0123] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different." [Explanation of symbols]

[0124] 1...power control system, 2, 2A...control unit, 10...server, 11...DR communication unit, 12...discharge power detection unit, 13...battery capacity detection unit, 14...memory unit, 15...duration calculation unit, 16...interval comparison unit, 17...base station selection unit, 18...discharge decision unit, 19...battery capacity update unit, 2A...control unit, 81...power saving amount prediction unit, 82...discharge power detection unit, 83...battery capacity detection unit, 84...memory unit, 85...duration calculation unit, 86...interval comparison unit, 87...base station selection unit, 88...discharge decision unit, 89...battery capacity update unit, 91...control quantity measurement unit, 92...buffer station management unit, 93...correction unit.

Claims

1. a plurality of consumers including loads, rectifiers, and storage batteries; a control unit that controls the rectifiers and the storage batteries in the plurality of consumers, A power control system that performs power saving operations in the plurality of consumers based on a power saving request, The control unit divides the time period during which the power saving request is made into multiple unit times, selects a consumer from the multiple consumers that is to be subject to power saving control based on the amount of power saving request per unit time, and responds to the power saving request by performing a discharge operation from the storage battery at the selected consumer.

2. The power control system of claim 1, wherein the control unit acquires output power information of the rectifier and current capacity information of the storage battery for each of the plurality of consumers, and selects a consumer to be subjected to the power saving control based on this information.

3. The power control system according to claim 1 , wherein the control unit selects the consumer as a target for the power saving control after ensuring a backup capacity of the storage battery in each of the plurality of consumers.

4. The power control system of claim 1, wherein the control unit compares the control amount related to power saving for the entire plurality of consumers with the power saving request amount, and when the control amount is insufficient for the power saving request amount, performs a discharge operation from the storage battery of a consumer other than the consumer responding to the power saving request.

5. The power control system of claim 4, wherein the control unit pre-stores information on consumers that are different from the consumer that responds to the power saving request and that are capable of discharging from the storage battery, and when the control amount is insufficient for the power saving request amount, selects the consumer that will perform discharging from the storage battery based on the information.

6. The power control system according to claim 1 , wherein the power saving request is a request for responding to a demand response request.

7. The power control system according to claim 1 , wherein the power saving request is a request to reduce a demand peak based on a forecast of power demand.

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