Control System

Abstract

The amount of power used in the entire power system is brought closer to the target value with high accuracy. [Solution] The control system manages the operation of a power system including a power storage system and at least one of a power generation system and a load system, and includes: a provisional power accumulation unit 41 that calculates a power accumulation value Ytmp(m), which is the accumulated value of the total power exchanged by the power system from the start of a unit period to a target time point within the unit period; a target value calculation unit 42 that calculates a provisional target value R(t) of the total power that should be exchanged by the power system at the target time point according to the power accumulation value Ytmp(m) and the period target value X so that the accumulated value of the total power exchanged by the power system over the entire unit period approaches the period target value X; and a command generation unit 43 that generates a command value for the power that should be charged and discharged by the power storage system so that the difference E(t) between the total power Y(t) of the power system at the target time point and the provisional target value R(t) is reduced.

Description

[Technical Field]

[0001] The present disclosure relates to a technique for controlling a power storage device. [Background technology]

[0002] In an electric power system including power generation equipment such as renewable energy power generation equipment or load equipment such as consumer business facilities, it is important to operate the system so that the actual power generation or actual demand approaches a target value (planned value). For example, Patent Document 1 discloses a technology that uses charging and discharging of an electricity storage device to avoid a deviation (imbalance) between the actual value and the planned value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2025-17255 Summary of the Invention [Problem to be solved by the invention]

[0004] However, it is not easy to accurately bring the amount of power in the entire power system close to the target value by using a power storage device. In consideration of the above circumstances, one aspect of the present disclosure aims to accurately bring the amount of power in the entire power system close to the target value. [Means for solving the problem]

[0005] In order to solve the above problems, a control system according to one aspect of the present disclosure is a control system that manages the operation of a power system that includes a power storage system and at least one of a power generation system and a load system, and includes: a provisional power accumulation unit that calculates a power accumulation value, which is the accumulated value of the total power exchanged by the power system from the start of a unit period to a target time point within the unit period; a target value calculation unit that calculates a provisional target value of the total power that should be exchanged by the power system at the target time point according to the power accumulation value and the period target value, so that the accumulated value of the total power exchanged by the power system throughout the unit period approaches the period target value; and a command generation unit that generates a command value for the power to be charged / discharged by the power storage system, so that the difference between the total power of the power system at the target time point and the provisional target value is reduced. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a block diagram illustrating a configuration of a power system according to a first embodiment. [Figure 2] FIG. 1 is a block diagram illustrating a configuration of a control system. [Figure 3] FIG. 10 is an explanatory diagram of a unit period. [Figure 4] FIG. 2 is a block diagram illustrating an example of the functional configuration of the control system. [Figure 5] 10 is a flowchart showing the procedure of an operation executed by a provisional power accumulation unit. [Figure 6] 10 is a flowchart showing the procedure of an operation executed by a target value calculation unit. [Figure 7] 10 is a flowchart showing the procedure of an operation executed by a command generating unit. [Figure 8] 10 is a graph illustrating the relationship between the control deviation E(t) and the amount of change ΔZ(t) in the power command value Z(t). [Figure 9] 10 is a graph showing the relationship between a power command value Z0(t) and a power command value Z(t). [Figure 10] 10 is a graph illustrating the relationship between the control deviation E(t) and the amount of change ΔZ(t) in the third embodiment. [Figure 11] This is the result of the simulation for comparison (Case 1). [Figure 12] 10 shows the results of a simulation (Case 1) in the third embodiment. [Figure 13] This is the result of the simulation for comparison (Case 2). [Figure 14] 10 shows the results of a simulation (Case 2) in the third embodiment. [Figure 15] This is the result of the simulation for comparison (Case 3). [Figure 16] 10 shows the results of a simulation (Case 3) in the third embodiment. [Figure 17] FIG. 10 is a block diagram illustrating an example of the functional configuration of a control system according to a fourth embodiment. [Figure 18] 10 shows the results of a simulation in the fourth embodiment. [Figure 19] FIG. 10 is a block diagram illustrating the configuration of a power management system according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The following description of an embodiment of the present disclosure will be given with reference to the accompanying drawings. Note that the embodiment described below is an exemplary embodiment that may be envisioned when implementing the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiment exemplified below.

[0008] A: First embodiment 1 is a block diagram illustrating the configuration of a power management system 100 according to a first embodiment. The power management system 100 is a system that transfers power to and from a power system 200. The power system 200 is, for example, a power distribution system or a power transmission system that supplies power generated by a power generation facility (not shown) such as a thermal power plant or a nuclear power plant to consumers such as business facilities or ordinary homes.

[0009] 1 , the power management system 100 includes a power system 11 and a control system 12. The power system 11 is configured with a plurality (N pieces of) power facilities 20 (N is a natural number of 2 or more) that exchange power with a power grid 200. The N pieces of power facilities 20 include a power storage system 21 and a plurality of power generation systems 22.

[0010] The power storage system 21 is a power facility 20 that can charge and discharge power. Specifically, as illustrated in FIG. 1 , the power storage system 21 includes a power storage device 211, an adjustment device 212, and a transformer device 213. The power storage device 211 is a system storage battery that charges and discharges DC power. Any type of power storage device 211 may be used, but examples of the power storage device 211 include secondary batteries such as lithium-ion batteries or sodium-sulfur batteries. Note that the power storage system 21 may include multiple power storage devices 211.

[0011] The adjusting device 212 is a PCS (Power Conditioning System) that controls discharging and charging of the power storage device 211. Specifically, the adjusting device 212 is a power conversion device that converts between DC power discharged or charged by the power storage device 211 and AC power transformed by the transformer device 213. The transformer device 213 converts the voltage of the AC power.

[0012] Each power generation system 22 is a power facility 20 capable of generating power. Specifically, as illustrated in Fig. 1 , the power generation system 22 includes a power generation device 221, an adjustment device 222, and a transformer device 223. The power generation device 221 is, for example, a distributed power source that generates power using renewable energy. For example, any type of power generation facility that uses renewable energy can be used as the power generation device 221, such as a solar power generation system that converts solar energy into electricity, a wind power generation system that converts wind energy into electricity, a geothermal power generation system that converts geothermal energy into electricity, a hydroelectric power generation system that converts hydroelectric energy into electricity, or a biomass power generation system that converts biomass energy into electricity.

[0013] The adjustment device 222 is a PCS (Power Conditioning System) that controls power generation by the power generation device 221. Specifically, the adjustment device 222 is a power conversion device that converts DC power generated by the power generation device 221 into AC power. The transformer 223 converts the voltage of the AC power converted by the adjustment device 222.

[0014] The control system 12 is a computer system (PMS: ​​Power Management System) that controls the operation of the power system 11. The control system 12 is capable of communicating with the power storage system 21 and each power generation system 22 via a communication network (not shown) such as a dedicated line.

[0015] Fig. 2 is a block diagram illustrating an example of the configuration of the control system 12. As illustrated in Fig. 2, the control system 12 includes a control device 31, a storage device 32, and a communication device 33. The control system 12 may be realized by a single device, or may be realized by multiple devices configured separately from each other.

[0016] The control device 31 is composed of one or more processors that control each element of the control system 12. Specifically, the control device 31 is composed of one or more types of processors, such as a programmable logic device (PLD), a central processing unit (CPU), a digital signal processor (DSP), a field programmable gate array (FPGA), or an application specific integrated circuit (ASIC).

[0017] The storage device 32 is one or more memories that store programs executed by the control device 31 and data used by the control device 31. The storage device 32 is configured with a known storage medium such as a magnetic storage medium or a semiconductor storage medium. The storage device 32 may also be configured with a combination of multiple types of storage medium. A portable storage medium that can be attached to and detached from the control system 12 may also be used as the storage device 32.

[0018] The communication device 33 transmits and receives signals to and from external devices via wired or wireless connections. Specifically, the communication device 33 communicates with each power facility 20 of the power system 11 via a communication network (not shown) such as a dedicated line. For example, the communication device 33 receives a power value Pn(t) (n=1 to N) from each power facility 20. The symbol t represents time. The power value Pn(t) is the instantaneous value of power exchanged with the n-th power facility 20 (the power storage system 21 or the power generation system 22) among the N power facilities 20 of the power system 11.

[0019] The power value P1(t) of the power storage system 21 is the power value of the power charged or discharged by the power storage system 21. Specifically, a negative number for the power value P1(t) of the power storage system 21 indicates charging by the power storage system 21 (i.e., power received by the power storage system 21 from the power grid 200). On the other hand, a positive number for the power value P1(t) of the power storage system 21 indicates discharging by the power storage system 21 (i.e., power supplied from the power storage system 21 to the power grid 200).

[0020] The power value Pn(t) of the power generation system 22 is the power value of the power generated by the power generation system 22. A positive number for the power value Pn(t) of the power generation system 22 means power generation by the power generation system 22 (i.e., power supply from the power generation system 22 to the power grid 200).

[0021] The communication device 33 receives the charging rate S(t) of the power storage device 211 in the power storage system 21 from the power storage system 21 (adjustment device 212). The charging rate S(t) is the ratio (SOC: State of Charge) of the current charge amount to the capacity (full charge capacity) of the power storage device 211.

[0022] The communication device 33 also communicates with the management system 300. The management system 300 is a computer system (EMS: Energy Management System) that manages electricity transactions in various electricity markets such as the wholesale electricity market or the supply and demand adjustment market.

[0023] The communication device 33 receives the operation plan from the management system 300. The operation plan specifies a planned value of the amount of power that the power system 11 should exchange with the power grid 200. Specifically, as illustrated in FIG. 3 , the operation plan specifies a start time ts, an end time te, and a period target value X for each of a plurality of unit periods U on the time axis. The unit periods U are periods of a predetermined length (e.g., 30 minutes) that are set without overlapping with each other on the time axis. The start time ts is the start time of the unit period U, and the end time te is the end time of the unit period U. The period target value X is a target value for the amount of power that the power system 11 should exchange with the power grid 200 within the unit period U (i.e., the integrated value of the power value over the unit period U).

[0024] The control system 12 generates a command value (hereinafter referred to as "power command value Z(t)") for the power to be charged or discharged by the power storage system 21. The communication device 33 transmits the power command value Z(t) to the power storage system 21 (specifically, the adjustment device 212). A negative number of the power command value Z(t) is a command for charging the power storage system 21, and a positive number of the power command value Z(t) is a command for discharging by the power storage system 21.

[0025] 4 is a block diagram illustrating an example of the functional configuration of the control system 12. The control device 31 executes a program stored in the storage device 32 to realize a plurality of functions (a provisional power accumulation unit 41, a target value calculation unit 42, and a command generation unit 43) for controlling the power system 11 (specifically, the power storage system 21).

[0026] The provisional power accumulation unit 41 calculates an accumulated power value Ytmp(m). As illustrated in FIG. 3, the accumulated power value Ytmp(m) is an accumulated value of the total power exchanged by the power system 11 from the start time ts of each unit period U to a specific time point within the unit period U (hereinafter referred to as "target time point t"). The accumulated power value Ytmp(m) is calculated by setting each of multiple time points set at a predetermined cycle Ta within the unit period U as the target time point t. The symbol m is a variable (e.g., the number of each target time point t) for identifying each of the multiple target time points t within each unit period U. The cycle Ta is a predetermined time length (e.g., 1 minute) shorter than the time length of the unit period U (e.g., 30 minutes).

[0027] Fig. 5 is a flowchart showing the procedure of the operation executed by the provisional power accumulation unit 41. The process of Fig. 5 is executed for each period Ta.

[0028] The provisional power accumulation unit 41 determines whether the target time t (current time) is between the start time ts and the end time te of the unit period U (Sa1). If the target time t is not within the unit period U (Sa1: NO), this means that the processed unit period U has elapsed and the next unit period U has started. Therefore, the provisional power accumulation unit 41 initializes the variable m to 1 and the accumulated power value Ytmp(m) to 0 (Sa2).

[0029] On the other hand, if the target time point t is within the unit period U (Sa1: YES), the provisional power accumulation unit 41 updates the accumulated power value Ytmp(m) (Sa3, Sa4). Specifically, the provisional power accumulation unit 41 adds 1 to the variable m (Sa3) and calculates the accumulated power value Ytmp(m) corresponding to the updated variable m (Sa4). For example, the provisional power accumulation unit 41 calculates the accumulated power value Ytmp(m) by calculating the following equation (1).

number

[0030] The sum ΣPn(t) in formula (1) is the total power obtained by adding up the power values ​​Pn(t) corresponding to the target time t across the N power facilities 20 of the power system 11. By multiplying the total power ΣPn(t) at the target time t by the period Ta, the amount of power exchanged by the power system 11 during the period of the period Ta immediately before the target time t is calculated. That is, by calculating formula (1), the integrated value of the total power exchanged by the power system 11 from the start time ts to the target time t is calculated as the integrated power value Ytmp(m).

[0031] 4 calculates a provisional target value R(t). The provisional target value R(t) is the total power that should be exchanged by the power system 11 at the target time t so that the integrated value of the total power exchanged by the power system 11 over the entire unit period U (integrated power value Ytmp(m)) approaches the period target value X for the unit period U. The target value calculation unit 42 calculates the provisional target value R(t) based on the integrated power value Ytmp(t) calculated by the provisional power accumulation unit 41 and the period target value X for the current unit period U.

[0032] Fig. 6 is a flowchart showing the procedure of the operation executed by the target value calculation unit 42. The process of Fig. 6 is executed for each period Ta.

[0033] The target value calculation unit 42 determines whether the target time t is a time point between the start time ts and the end time te of the unit period U (Sb1). If the target time t is not a time point within the unit period U (Sb1: NO), the target value calculation unit 42 initializes the provisional target value R(t) (Sb2). Specifically, the target value calculation unit 42 initializes the provisional target value R(t) to a numerical value expressed by the following formula (2).

number

[0034] On the other hand, if the target time t is within the unit period U (Sb1: YES), the target value calculation unit 42 calculates a provisional target value R(t) for the target time t (Sb3, Sb4). The target value calculation unit 42 first calculates the length of time Tr of the remaining period (Sb3). As illustrated in FIG. 3, the remaining period is the period within the unit period U from the target time t to the end point (end time te) of the unit period U. That is, the target value calculation unit 42 calculates the length of time Tr of the remaining period using the following equation (3):

number

[0035] The target value calculation unit 42 calculates a provisional target value R(t) by the calculation of the following equation (4) (Sb4).

number

[0036] As can be understood from the above explanation, assuming that the total power of power system 11 is maintained at provisional target value R(t) for the remaining period of unit period U after target time t, the integrated value of the total power exchanged by power system 11 over the entire unit period U reaches period target value X at the end time te of unit period U. In other words, provisional target value R(t) is a target value of the total power that power system 11 should exchange at target time t in order to make the amount of power exchanged between power system 11 and the power grid 200 over the entire unit period U approach (ideally match) the period target value X.

[0037] 4 generates a power command value Z(t) that represents the power to be charged or discharged by the power storage system 21. Specifically, the command generator 43 calculates the power command value Z(t) so that the difference (hereinafter referred to as "control deviation E(t)") between the total power Y(t) of the power system 11 at the target time t and the provisional target value R(t) is reduced. In other words, the power command value Z(t) is calculated so that the total power Y(t) of the power system 11 approaches the provisional target value R(t).

[0038] Fig. 7 is a flowchart showing the procedure of the operation executed by the command generating unit 43. The process of Fig. 7 is executed at every predetermined cycle Tc. The cycle Tc is a predetermined time length (e.g., 10 seconds) that is shorter than the time length of the unit period U (e.g., 30 minutes). The cycle Tc is a time length shorter than the aforementioned cycle Ta.

[0039] The command generation unit 43 calculates the total power Y(t) of the power system 11 at the target time t (Sc1). The total power Y(t) is a numerical value obtained by summing up the power values ​​Pn(t) corresponding to the target time t across the N pieces of power equipment 20 in the power system 11. Specifically, the command generation unit 43 calculates the total power Y(t) by calculating the following equation (5).

number

[0040] The command generating unit 43 calculates the control deviation E(t) by the calculation of the formula (6) (Sc2).

number

[0041] The command generating unit 43 calculates the power command value Z(t) according to the control deviation E(t) (Sc3 to Sc5). Specifically, the command generating unit 43 changes the power command value Z(t) according to the control deviation E(t).

[0042] First, the command generator 43 calculates the change amount ΔZ(t) of the power command value Z(t) according to the control deviation E(t) (Sc3). FIG. 8 is a graph illustrating the relationship between the control deviation E(t) and the change amount ΔZ(t). As illustrated in FIG. 8, the change amount ΔZ(t) is proportional to the control deviation E(t). The gradient K of the change amount ΔZ(t) relative to the control deviation E(t) is set to a predetermined positive number.

[0043] 8, as the control deviation E(t) increases within the range of positive numbers (i.e., as the total power Y(t) becomes smaller than the provisional target value R(t)), the change amount ΔZ(t) of the power command value Z(t) increases within the range of positive numbers. On the other hand, as the control deviation E(t) decreases within the range of negative numbers (i.e., as the total power Y(t) becomes larger than the provisional target value R(t)), the change amount ΔZ(t) of the power command value Z(t) decreases within the range of negative numbers.

[0044] The command generator 43 calculates the power command value Z0(t) at the target time point t by adding the change ΔZ(t) to the immediately preceding power command value Z(t-Tc) (Sc4). That is, the command generator 43 calculates the power command value Z0(t) by the calculation of the following formula (7).

number

[0045] The command generation unit 43 calculates the final power command value Z(t) by restricting the power command value Z0(t) calculated by the above procedure within a predetermined range (hereinafter referred to as the "restriction range Lz") (Sc5). FIG. 9 is a graph showing the relationship between the power command value Z0(t) and the power command value Z(t). The restriction range Lz in FIG. 9 is the range between the upper limit value ZH and the lower limit value ZL. The upper limit value ZH is a predetermined positive number, and the lower limit value ZL is a predetermined negative number. For example, the lower limit value ZL is a negative number whose absolute value is equal to the upper limit value ZH (ZL = -ZH).

[0046] As illustrated in FIG. 9, when the power command value Z0(t) exceeds the upper limit value ZH (Z0(t)>ZH), the command generation unit 43 sets the power command value Z(t) to the upper limit value ZH. Further, when the power command value Z0(t) is lower than the lower limit value ZL (Z0(t)<ZL), the command generation unit 43 sets the power command value Z(t) to the lower limit value ZL. On the other hand, when the power command value Z0(t) is a numerical value within the restriction range Lz (ZL≦Z0(t)≦ZH), the command generation unit 43 determines the power command value Z0(t) as the final power command value Z(t).

[0047] After calculating the power command value Z(t) by the above procedure, the command generation unit 43 determines whether or not the power storage system 21 is in a state where it can be charged according to the power command value Z(t) (Sc6). Specifically, the command generation unit 43 determines whether the power command value Z(t) is a negative number indicating charging (Z(t)<0) and whether the charging rate S(t) at the target time t is lower than a predetermined upper limit value SH (S(t)<SH).

[0048] If the result of the determination is positive (Sc6: YES), the power storage system 21 is in a state where it can be charged according to the power command value Z(t). Therefore, the command generator 43 transmits the power command value Z(t) at the target time point t to the power storage system 21 from the communication device 33 (Sc9). The power storage device 211 of the power storage system 21 performs charging according to the power command value Z(t).

[0049] If the result of the determination is negative (Sc6: NO), the command generating unit 43 determines whether the power storage system 21 is in a state where it can discharge in accordance with the power command value Z(t) (Sc7). Specifically, the command generating unit 43 determines whether the power command value Z(t) is a positive number indicating discharge (Z(t)>0) and whether the charging rate S(t) at the target time t exceeds a predetermined lower limit value SL (S(t)>SL).

[0050] If the result of the determination is positive (Sc7: YES), the power storage system 21 is in a state where it can discharge in accordance with the power command value Z(t). Therefore, the command generator 43 transmits the power command value Z(t) at the target time point t to the power storage system 21 from the communication device 33 (Sc9). The power storage device 211 of the power storage system 21 executes discharge in accordance with the power command value Z(t).

[0051] If the determination results in both steps Sc6 and Sc7 are negative, the power storage system 21 is in a state in which it cannot perform charging or discharging. If the power storage system 21 cannot perform charging or discharging (Sc6: NO and Sc7: NO), the command generator 43 limits the power command value Z(t) to 0, which means that charging or discharging is stopped (Sc8). The power storage system 21 transmits the power command value Z(t) to the power storage system 21 (Sc9). Therefore, the power storage system 21 does not perform charging or discharging. Note that if the power storage system 21 cannot perform charging or discharging, the transmission of the power command value Z(t) to the power storage system 21 (Sc9) may be omitted.

[0052] As described above, in the first embodiment, the provisional target value R(t) of the total power at the target time t is calculated so that the integrated value of the total power exchanged by the power system 11 over the entire unit period U approaches the period target value X, and the power command value Z(t) for the power storage system 21 is generated so that the difference (control deviation E(t)) between the total power Y(t) at the target time t and the provisional target value R(t) at the target time t is reduced. Therefore, it is possible to bring the integrated value of the total power of the power system 11 over the entire unit period U close to the period target value X.

[0053] B: Second embodiment A second embodiment of the present disclosure will be described. In each aspect exemplified below, elements having the same functions as those in the first embodiment will be denoted by the same reference numerals as those in the first embodiment, and detailed descriptions thereof will be omitted as appropriate.

[0054] As shown in equation (4) above, the target value calculation unit 42 calculates the provisional target value R(t) by dividing the difference (X-Ytmp(m)) between the integrated power value Ytmp(m) and the period target value X by the length of the remaining period Tr. Therefore, when the length of the remaining period Tr shortens as the target time t approaches the end time te of the unit period U, the provisional target value R(t) may increase unstably. In consideration of the above, the target value calculation unit 42 of the second embodiment maintains the provisional target value R(t) constant during the final period Ue (see FIG. 3) that includes the end point of the unit period U, regardless of the integrated power value Ytmp(t) and the period target value X.

[0055] Specifically, the target value calculation unit 42 of the second embodiment calculates the provisional target value R(t) by calculation of the following formula (4a) instead of formula (4) of the first embodiment.

number

[0056] The duration of the end period Ue, which includes the end time te of the unit period U, corresponds to 10% of the duration (te-ts) of the unit period U. When the target time t is before the start of the end period Ue (Tr≧(te-ts)×0.1), the target value calculation unit 42 calculates the provisional target value R(t) by dividing the difference (X-Ytmp(m)) between the integrated power value Ytmp(m) and the period target value X by the duration Tr of the remaining period, as in the first embodiment. On the other hand, when the target time t is within the end period Ue (Tr<(te-ts)×0.1), the target value calculation unit 42 sets the immediately preceding provisional target value R(t-Ta) as the provisional target value R(t) for the target time t (current time). Therefore, the provisional target value R(t) within the end period Ue is maintained at the provisional target value R(t) at the start time ts of the end period Ue.

[0057] The second embodiment also achieves the same effects as the first embodiment. Furthermore, in the second embodiment, the provisional target value R(t) is maintained constant in the final period Ue of the unit period U, so that the provisional target value R(t) can be stabilized even in the final period Ue.

[0058] C: Third embodiment The command generator 43 of the first embodiment generates a power command value Z(t) according to the difference (control deviation E(t)) between the total power Y(t) and the provisional target value R(t). As can be seen from FIG. 8, when the control deviation E(t) fluctuates around 0, the amount of change ΔZ(t) may frequently fluctuate between positive and negative values. As a result of the frequent fluctuations in the amount of change ΔZ(t), the power command value Z(t) may fluctuate unstably. In consideration of the above circumstances, the command generator 43 of the third embodiment does not change the power command value Z(t) when the control deviation E(t) is within a predetermined range.

[0059] Fig. 10 is a graph illustrating the relationship between the control deviation E(t) and the change amount ΔZ(t) in the third embodiment. That is, in the third embodiment, the relationship between the control deviation E(t) and the change amount ΔZ(t) is replaced from the relationship illustrated in Fig. 8 to the relationship illustrated in Fig. 10.

[0060] As illustrated in FIG. 10, when the control deviation E(t) is within a predetermined range Le, the command generator 43 sets the change amount ΔZ(t) of the power command value Z(t) to 0. The range Le is the range between an upper limit value EH and a lower limit value EL. The upper limit value EH is a predetermined positive number, and the lower limit value EL is a predetermined negative number. For example, the lower limit value EL is a negative number whose absolute value is equal to the upper limit value EH (EL=-EH). As a result of setting the change amount ΔZ(t) to 0 as described above, the power command value Z(t) does not change, as can be seen from the above-mentioned equation (7).

[0061] The operation when the control deviation E(t) is outside the predetermined range Le is the same as in the first embodiment. That is, when the control deviation E(t) exceeds the upper limit value EH of the range Le, the change amount ΔZ(t) is set to a positive number, and the power command value Z(t) increases. On the other hand, when the control deviation E(t) is below the lower limit value EL of the range Le, the change amount ΔZ(t) is set to a negative number, and the power command value Z(t) decreases.

[0062] The third embodiment also achieves the same effects as the first embodiment. Furthermore, in the third embodiment, if the difference (control deviation E(t)) between the total power Y(t) at a target time t and the provisional target value R(t) at the target time t is within a predetermined range Le, the power command value Z(t) is not changed. Therefore, it is possible to reduce the possibility that the power command value Z(t) will fluctuate unstably due to fluctuations in the control deviation E(t) within the range Le. For example, it is possible to reduce the possibility that the power command value Z(t) will frequently switch between a negative number representing charging and a positive number representing discharging. Note that the configuration of the second embodiment can also be applied to the third embodiment.

[0063] 11 to 16 show the results of a simulation in the third embodiment. The conditions for the following simulation are as follows: The capacity of the power storage device 211 was set to 30 [MWh]. N=2 (power system 11 is configured with one power storage system 21 and one power generation system 22) ts=0[min], te=30[min] SH=90[%], SL=10[%] EH=2[MW], EL=-2[MW] K=1.5 Ta=1 [min] Tc=10[seconds] ZH=15[MW], ZL=-15[MW]

[0064] In the following description, graph G1 is a graph showing changes over time in the period target value X and the integrated power value Ytmp(t). Graph G2 is a graph showing changes over time in the power value P1(t) of the power storage system 21, the power value P2(t) of the power generation system 22, and the charging rate S(t) of the power storage device 211. Graph G3 is a graph showing changes over time in the power command value Z(t), the control deviation E(t), and the provisional target value R(t). The adjustment device 212 outputs the power value P1(t) of graph G2 in accordance with the power command value Z(t) shown in graph G3.

[0065] Case 1 assumed in Fig. 11 and Fig. 12 is a situation in which the period target value X is set to 10 [MWh]. Fig. 11 shows the results of a simulation in a form in which the power command value Z(t) of the power storage system 21 is not controlled (hereinafter referred to as the "comparative example"). As can be seen from Fig. 11, in the comparative example, the integrated power value Ytmp(m) at the end time te of the unit period U is a value that deviates from the period target value X. Specifically, the shortfall δ (shortfall imbalance) of the integrated power value Ytmp(m) with respect to the period target value X is 2.12 [MWh].

[0066] Fig. 12 shows the results of a simulation in the third embodiment. As can be seen from Fig. 12, in the third embodiment, the integrated power value Ytmp(m) at the end time te of the unit period U substantially matches the period target value X. Specifically, the difference between the period target value X and the integrated power value Ytmp(m) is suppressed to 0.04 [MWh].

[0067] Case 2 assumed in Figures 13 and 14 is a situation in which the period target value X is set to 5 [MWh]. Figure 13 shows the results of a simulation in the comparative example. As can be seen from Figure 13, in the comparative example, the integrated power value Ytmp(m) at the end time te of the unit period U is a value that deviates from the period target value X. Specifically, the surplus δ (surplus imbalance) of the integrated power value Ytmp(m) with respect to the period target value X is 2.63 [MWh].

[0068] Fig. 14 shows the results of a simulation in the third embodiment. As can be seen from Fig. 14, in the third embodiment, the integrated power value Ytmp(m) at the end time te of the unit period U substantially matches the period target value X. Specifically, the difference between the period target value X and the integrated power value Ytmp(m) is suppressed to 0.07 [MWh]. As described above, according to the third embodiment, it is possible to bring the integrated value of the total power of the power system 11 over the entire unit period U close to the period target value X with high accuracy.

[0069] 15 and 16 show the simulation results for Case 3, in which the period target value X changes from 5 [MWh] to 10 [MWh] midway through the unit period U. Fig. 15 shows the simulation results for the comparative example. In the comparative example, the shortfall δ (shortfall imbalance) of the integrated power value Ytmp(m) relative to the period target value X is 2.37 [MWh].

[0070] Fig. 16 shows the results of a simulation in the third embodiment. As can be seen from Fig. 16, in the third embodiment, the integrated power value Ytmp(m) at the end time te of the unit period U substantially matches the period target value X. Specifically, the difference between the period target value X and the integrated power value Ytmp(m) is suppressed to 0.16 [MWh]. As described above, according to the third embodiment, even if the period target value X changes within the unit period U, it is possible to make the integrated value of the total power of the power system 11 approach the period target value X with high accuracy.

[0071] D: Fourth embodiment 17 is a block diagram illustrating an example of the functional configuration of a control system 12 according to the fourth embodiment. A control device 31 according to the fourth embodiment executes a program stored in a storage device 32, thereby functioning as a smoothing processing unit 44 in addition to the same elements as those in the first embodiment (a provisional power accumulator 41, a target value calculator 42, and a command generator 43).

[0072] The smoothing processor 44 smoothes, on the time axis, the time series of power values ​​Pn(t) exchanged by each power facility 20 in the power system 11. For example, the smoothing processor 44 is exemplified by a low-pass filter that removes high-frequency components from the time series of power values ​​Pn(t).

[0073] For example, the smoothing processor 44 calculates the smoothed power value Vn(t) using an ARMA (AutoRegressive Moving Average) filter expressed by the following equation (8).

number

[0074] The control device 31 of the fourth embodiment applies the power value Vn(t) after smoothing by the smoothing processing unit 44 as the power value Pn(t) in each of the above-mentioned embodiments. For example, the provisional power accumulation unit 41 calculates the accumulated power value Ytmp(t) by accumulating the total power ΣVn(t) of the smoothed power values ​​Vn(t).

[0075] The fourth embodiment also achieves the same effects as the first embodiment. Furthermore, in the fourth embodiment, the power value Pn(t) of each power equipment 20 in the power system 11 is smoothed on the time axis, and the integrated power value Ytmp(t) is calculated from each smoothed power value Vn(t). Therefore, compared to a configuration in which the power value Pn(t) of each power equipment 20 is not smoothed, excessive fluctuations in the power command value Z(t) caused by frequent fluctuations in the power value Pn(t) of each power equipment 20 can be suppressed. Note that the configurations of the second or third embodiment can also be applied to the fourth embodiment.

[0076] Fig. 18 shows the results of a simulation in the fourth embodiment. The simulation conditions are the same as those of the simulations illustrated in Figs. 11 and 12. Note that the order I of the autoregressive component and the order J of the moving average component in equation (8) were both set to 1. Furthermore, the autoregressive coefficient ai in equation (8) was set to 0.9, and the moving average coefficient bj was set to 0.1. The period target value X was 10 [MWh].

[0077] As can be seen from Fig. 18, in the fourth embodiment as well, the integrated power value Ytmp(m) at the end time te of the unit period U substantially coincides with the period target value X. Specifically, the difference between the period target value X and the integrated power value Ytmp(m) is suppressed to 0.009 [MWh]. Furthermore, it can be seen from Fig. 18 that in the fourth embodiment, the temporal fluctuation of the power command value Z(t) is suppressed compared to the third embodiment (Fig. 12).

[0078] E: Fifth embodiment 19 is a block diagram illustrating the configuration of a power management system 100 according to a fifth embodiment. In the first embodiment, a form in which a power system 11 is configured with a power storage system 21 and a power generation system 22 is exemplified. N power facilities 20 constituting the power system 11 of the fifth embodiment include a power storage system 21 similar to that of the first embodiment, and a plurality of load systems 23. That is, in the fifth embodiment, the power generation system 22 of the first embodiment is replaced with a load system 23.

[0079] Each load system 23 is a type of load (in-station load) that operates by consuming power supplied from the power storage system 21 or the power grid 200. The communication device 33 of the control system 12 receives a power value Pn(t) from each power facility 20 including the load system 23. The power value Pn(t) of the load system 23 is basically a negative number.

[0080] 19, the load system 23 includes a load device 231, an adjustment device 232, and a transformer device 233. The load device 231 is, for example, various types of equipment (such as a power supply device, a lighting device, or an air conditioning device) installed within the premises of the power system 11.

[0081] The transformer 233 transforms the voltage of AC power supplied from the power system 200. The adjustment device 232 is a PCS (Power Conditioning System) that controls the operation of the load device 231. Specifically, the adjustment device 232 is a power conversion device that converts the AC power converted by the transformer 233 into power suitable for the load device 231 (for example, DC power).

[0082] The configuration and operation of the control system 12 are the same as those in the first embodiment. Therefore, the fifth embodiment also achieves the same effects as those in the first embodiment. Note that one or more of the configurations of the second to fourth embodiments can also be applied to the fifth embodiment.

[0083] The power system 11 may include both the power generation system 22 exemplified in the first embodiment and the load system 23 exemplified in the fifth embodiment. As can be understood from the above examples, the power system 11 includes the power storage system 21 and at least one of the power generation system 22 and the load system 23.

[0084] F: Variation Specific modified embodiments that can be added to each of the embodiments exemplified above are exemplified below. Two or more embodiments arbitrarily selected from the following examples may be combined as appropriate within the scope of not being mutually contradictory.

[0085] (1) In the second embodiment, the end period Ue is set to 10% of the duration (te-ts) of the unit period U, but the condition for the end period Ue is not limited to this example. For example, the duration of the end period Ue may be a preset fixed value (e.g., 3 minutes).

[0086] (2) In the above-described embodiments, the power system 11 includes one power storage system 21. However, the power system 11 may include a plurality of power storage systems 21. The control exemplified in the above-described embodiments is applied to each of the plurality of power storage systems 21.

[0087] (3) As described above, the functions of the control system 12 according to the above-described embodiment are realized through cooperation between one or more processors constituting the control device 31 and a program stored in the storage device 32. The programs exemplified above can be provided in a form stored on a computer-readable recording medium and installed on a computer. The recording medium is, for example, a non-transitory recording medium, such as an optical recording medium (optical disk) such as a CD-ROM, but also includes any known type of recording medium, such as a semiconductor recording medium or a magnetic recording medium. Note that a non-transitory recording medium includes any recording medium other than a transitory, propagating signal, and does not exclude volatile recording media. Furthermore, in a configuration in which a distribution device distributes a program via a communication network, the recording medium storing the program in the distribution device corresponds to the non-transitory recording medium described above.

[0088] (4) The term "nth" (n is a natural number) in this application is used only as a formal and convenient label to distinguish each element in the description and does not have any substantive meaning. Therefore, there is no room for restrictive interpretation of the position or order of each element based on the term "nth."

[0089] G: Notes The following configurations can be understood from the above-described exemplary embodiments. Note that, in order to facilitate understanding of each embodiment, reference numerals in the drawings are written in parentheses for convenience, but this is not intended to limit the present disclosure to the illustrated embodiments.

[0090] A control system (12) according to one aspect (aspect 1) of the present disclosure is a control system (12) that manages the operation of an electric power system (11) that includes a power storage system (21), a power generation system (22), and / or a load system (23), and includes a provisional electric power accumulation unit (41) that calculates an electric power accumulation value (Ytmp(m)) that is an accumulation value of total electric power exchanged by the electric power system (11) from a start point of a unit period (U) to a target time point (t) within the unit period (U), and a total electric power exchanged by the electric power system (11) throughout the unit period (U). a target value calculation unit (42) that calculates a provisional target value (R(t)) of total power to be exchanged by the power system (11) at the target time point (t) in accordance with the power integrated value (Ytmp(m)) and the period target value (X) so that the integrated value approaches the period target value (X); and a command generation unit (43) that generates a command value (Z(t)) of power to be charged / discharged by the power storage system (21) so that a difference (E(t)) between the total power (Y(t)) of the power system (11) at the target time point (t) and the provisional target value (R(t)) is reduced. In the above-described aspect, a provisional target value of the total power at the target time (t) is calculated so that the integrated value of the total power exchanged by the power system (11) over the entire unit period (U) approaches the period target value (X), and a charge / discharge command is generated for the power storage system (21) so that the difference between the total power at the target time (t) and the provisional target value at the target time (t) is reduced. Therefore, it is possible to bring the integrated value of the total power of the power system (11) over the entire unit period (U) close to the period target value (X).

[0091] In a specific example (aspect 2) of aspect 1, the target value calculation unit (42) calculates the provisional target value (R(t)) by dividing the difference between the integrated power value (Ytmp(m)) and the period target value (X) by the length of time (Tr) of the remaining period from the target time point (t) to the end point of the unit period (U). According to the above aspect, by dividing the difference between the integrated power value (Ytmp(m)) and the period target value (X) by the length of time (Tr) of the remaining period, the provisional target value (R(t)) at the target time point (t) can be simply and appropriately calculated.

[0092] In a specific example (aspect 3) of aspect 2, the target value calculation unit (42) maintains the provisional target value (R(t)) constant during a final period (Ue) of the unit period (U) that includes the end point, regardless of the integrated power value (Ytmp(m)) and the period target value (X). As the target time (t) approaches the end point of the unit period (U), the length of the remaining period (Tr) becomes shorter. Therefore, the provisional target value (R(t)) calculated by dividing the difference between the integrated power value (Ytmp(m)) and the period target value (X) by the length of the remaining period (Tr) may fluctuate unstably during the final period (Ue) of the unit period (U). By maintaining the provisional target value (R(t)) constant during the final period (Ue), it is possible to stabilize the provisional target value (R(t)) even during the final period (Ue).

[0093] In a specific example (Aspect 4) of any of Aspects 1 to 3, the command generator (43) changes the command value (Z(t)) according to the difference (E(t)) between the total power (Y(t)) at the target time point (t) and the provisional target value (R(t)), and does not change the command value (Z(t)) when the difference (E(t)) is within a predetermined range. In the above aspect, the command value (Z(t)) is not changed when the difference between the total power at the target time point (t) and the provisional target value (R(t)) at the target time point (t) is within a predetermined range. This reduces the possibility that the command value (Z(t)) will fluctuate unstably due to fluctuations in the difference within the predetermined range. For example, it reduces the possibility that the command value (Z(t)) will frequently switch between a value representing charging and a value representing discharging.

[0094] In a specific example (Aspect 5) of any of Aspects 1 to 4, the power system (11) further includes a smoothing processor (44) that smooths, on a time axis, a time series of power values ​​(Pn(t)) exchanged by each power facility (20) included in the power system (11), and the provisional power integrator (41) calculates the integrated power value (Ytmp(m)) by integrating the total power of the power values ​​(Pn(t)) smoothed by the smoothing processor (44). In the above aspect, the power values ​​of each power facility (20) of the power system (11) are smoothed on a time axis, and the integrated power value Ytmp(t) is calculated from each smoothed power value. Therefore, compared to an aspect in which the power values ​​of each power facility (20) are not smoothed, excessive fluctuations in the power command value (Z(t)) caused by frequent fluctuations in the power value of each power facility (20) can be suppressed. [Explanation of symbols]

[0095] 100...power management system, 200...power system, 300...management system, 11...power system, 12...control system, 20...power equipment, 21...power storage system, 211...power storage device, 212...adjustment device, 213...transformer device, 22...power generation system, 221...power generation device, 222...adjustment device, 223...transformer device, 23...load system, 231...load device, 232...adjustment device, 233...transformer device, 31...control device, 32...storage device, 33...communication device, 41...provisional power accumulation unit, 42...target value calculation unit, 43...command generation unit, 44...smoothing processing unit

Claims

1. A control system that manages the operation of a power system including a power storage system and at least one of a power generation system and a load system, a provisional power accumulation unit that calculates an accumulated power value that is an accumulated value of total power exchanged by the power system from a start point of a unit period to a target time point within the unit period; a target value calculation unit that calculates a provisional target value of total power to be exchanged by the power system at the target time point by dividing a difference between the integrated power value and the period target value by a remaining period from the target time point to an end point of the unit period so that the integrated value of total power exchanged by the power system over the entire unit period approaches the period target value; a command generating unit that generates a command value for power to be charged or discharged by the power storage system so that a difference between the total power of the power system at the target time point and the provisional target value is reduced; Equipped with The target value calculation unit maintains the provisional target value constant during a final period including an end point of the unit period, regardless of the integrated power value and the period target value. Control system.

2. A control system that manages the operation of a power system including a power storage system and at least one of a power generation system and a load system, a provisional power accumulation unit that calculates an accumulated power value that is an accumulated value of total power exchanged by the power system from a start point of a unit period to a target time point within the unit period; a target value calculation unit that calculates a provisional target value of total power to be exchanged by the power system at the target time point in accordance with the integrated power value and the period target value so that the integrated value of total power exchanged by the power system over the entire unit period approaches the period target value; a command generating unit that generates a command value for power to be charged or discharged by the power storage system so that a difference between the total power of the power system at the target time point and the provisional target value is reduced; Equipped with The command generation unit changing the command value according to a difference between the total power at the target time point and the provisional target value; If the difference is within a predetermined range, the command value is not changed. Control system.

3. A control system that manages the operation of a power system including a power storage system and at least one of a power generation system and a load system, a smoothing processor that smoothes, on a time axis, a time series of power values ​​exchanged by each power facility included in the power system; a provisional power accumulation unit that calculates an accumulated power value that is an accumulated value of total power exchanged by the power system from a start point of a unit period to a target time point within the unit period; a target value calculation unit that calculates a provisional target value of total power to be exchanged by the power system at the target time point in accordance with the integrated power value and the period target value so that the integrated value of total power exchanged by the power system over the entire unit period approaches the period target value; a command generating unit that generates a command value for power to be charged or discharged by the power storage system so that a difference between the total power of the power system at the target time point and the provisional target value is reduced; Equipped with The provisional power accumulator calculates the power accumulation value by accumulating a total power of the power values ​​smoothed by the smoothing processor. Control system.

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