Planning System and Planning Method

Abstract

Generate an appropriate operation plan considering the decrease in the charge amount of the power storage device. 【Solution means】 The planning system is a planning system that generates an operation plan regarding the charge and discharge of a power storage device capable of providing primary regulation power to the power grid. Based on the charge and discharge efficiency of the power storage device and the frequency information regarding the system frequency in the power grid, a first calculation unit 51 that calculates a first activation rate k1(i) corresponding to the loss due to the charge and discharge of the primary regulation power, a second calculation unit 52 that calculates the average charge and discharge power Pa(i) of the power storage device based on the committed power of the regulation power and the first activation rate k1(i), and a plan generation unit 53 that generates an operation plan X of the power storage device based on the average charge and discharge power Pa(i).

Description

Technical Field

[0001] The present disclosure relates to a technique for generating a plan (hereinafter referred to as an "operation plan") for charging and discharging a power storage device.

Background Art

[0002] Power storage devices such as storage batteries are used to provide regulating power to the power system. For example, Patent Document 1 discloses a configuration for calculating a charge-discharge power amount for canceling the difference between the change amount of the stored power amount based on the charge-discharge power amount of the storage battery in the first period and the reference amount of the change in the stored power amount based on the reference value of the charge-discharge power of the storage battery in the first period.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Regarding the primary regulating power in particular among the regulating powers, frequent switching between charging and discharging in the power storage device is required to cope with fluctuations in the frequency of the power system. As a result of the frequent switching between charging and discharging, the charged amount of the power storage device decreases. Therefore, it is difficult to generate an appropriate operation plan for the power storage device. In view of the above circumstances, one aspect of the present disclosure aims to generate an appropriate operation plan considering the decrease amount of the charged amount of the power storage device.

Means for Solving the Problems

[0005] A planning system according to one aspect of the present disclosure is a planning system that generates an operation plan regarding charging and discharging of a power storage device capable of providing primary frequency regulation power to a power grid, the planning system including: a first calculation unit that calculates a first activation rate corresponding to a loss due to charging and discharging of the primary frequency regulation power based on a charging efficiency and a discharging efficiency of the power storage device and frequency information regarding a system frequency in the power grid; a second calculation unit that calculates an average charging and discharging power of the power storage device based on a contracted power of the regulation power and the first activation rate; and a plan generation unit that generates an operation plan of the power storage device based on the average charging and discharging power.

[0006] A planning method according to one aspect of the present disclosure is a planning method that generates an operation plan regarding charging and discharging of a power storage device capable of providing primary frequency regulation power to a power grid, the method including: the planning system calculating a first activation rate corresponding to a loss due to charging and discharging of the primary frequency regulation power based on a charging efficiency and a discharging efficiency of the power storage device and frequency information regarding a system frequency in the power grid; the planning system calculating an average charging and discharging power of the power storage device based on a contracted power of the regulation power and the first activation rate; and the planning system generating an operation plan of the power storage device based on the average charging and discharging power.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

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Figure 8

Embodiments for Carrying Out the Invention

[0008] Embodiments for carrying out the present disclosure will be described with reference to the drawings. Note that the embodiments described below are exemplary embodiments assumed when carrying out the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiments illustrated below.

[0009] A: First Embodiment FIG. 1 is a block diagram illustrating the configuration of a power system 100 according to the first embodiment of the present disclosure. The power system 100 is a system that exchanges AC power with the power grid 10. The power grid 10 is, for example, a power distribution grid or a power transmission grid for supplying 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 households.

[0010] As illustrated in FIG. 1, the power system 100 includes a power storage system 20, a control system 30, and a planning system 40. The power storage system 20, the control system 30, and the planning system 40 can communicate with each other via a communication network (not shown), such as a dedicated line. Note that the power system 100 may include a plurality of power storage systems 20, but in the following description, for convenience, attention is focused on one power storage system 20.

[0011] The power storage system 20 is connected to the power grid 10 at the connection point 11. The power storage system 20 is a power facility capable of supplying power (i.e., discharging) to the power grid 10 and receiving power (i.e., charging) from the power grid 10. That is, the power storage system 20 adjusts the power at the connection point 11 in the power grid 10 (hereinafter referred to as "connection point power") by charging and discharging. Specifically, the power storage system 20 can provide, for example, a regulating power including primary regulating power to the power grid 10. The primary regulating power is a regulating power that requires instantaneous charging and discharging to suppress fluctuations in the frequency of the connection point power.

[0012] The power storage system 20 includes a power storage device 21 and a control device 22. The power storage device 21 is a power facility (power storage device) that stores power. Specifically, the power storage device 21 is a system battery that discharges and charges DC power. The type of the power storage device 21 is arbitrary, and for example, a secondary battery such as a lithium-ion battery or a sodium-sulfur battery is exemplified as the power storage device 21. In FIG. 1, the power storage device 21 is illustrated as one element for convenience, but the power storage device 21 may be composed of a plurality of storage batteries.

[0013] The control device 22 is a PCS (Power Conditioning System) that controls the discharge and charge of the power storage device 21. Specifically, the control device 22 is a power conversion device that mutually converts the DC power that the power storage device 21 discharges or charges and the AC power that the power grid 10 transmits. The illustration of the voltage conversion facility for converting the AC power voltage between the power storage system 20 and the power grid 10 is omitted for convenience. In FIG. 1, only one set of the power storage device 21 and the control device 22 is illustrated for convenience, but the power storage system 20 may be composed of a plurality of sets of the power storage device 21 and the control device 22.

[0014] The planning system 40 is a computer system (EMS: Energy Management System) that generates an operation plan X. The operation plan X is a plan regarding the charging and discharging of the energy storage device 21. The operation plan X designates the planned value of the amount of electric power that the energy storage device 21 should charge or discharge for each unit period of a predetermined length. Each unit period is, for example, a period of 30 minutes.

[0015] The planning system 40 receives trading information Y1 from a management system (not shown) that manages power trading in, for example, the supply-demand adjustment market. The trading information Y1 is information regarding power trading such as regulation power, for example. Also, the planning system 40 receives operation results Y2 from the control system 30. The operation results Y2 are the results of the transfer of electric power by the energy storage system 20. The planning system 40 generates the operation plan X based on the trading information Y1 and the operation results Y2.

[0016] The control system 30 is a computer system (PMS: Power Management System) that controls the energy storage system 20. Specifically, the control system 30 transmits an operation command Z to the energy storage system 20. The operation command Z includes the command value of the electric power that the energy storage device 21 should charge or discharge.

[0017] The control system 30 receives the operation plan X generated by the planning system 40. Also, the control system 30 receives the operation results Y2 from the energy storage system 20 (control device 22). The operation results Y2 are transmitted from the control system 30 to the planning system 40.

[0018] The control system 30 receives a regulation power command value Y3 from the central power supply command system (central power supply system). The regulation power command value Y3 is the command value of the regulation power that should be dynamically supplied according to the relationship between demand and supply in the supply-demand adjustment market. Also, the control system 30 generates a regulation power command value Y4 for primary frequency regulation. The control system 30 generates the regulation power command value Y4 for primary frequency regulation according to the frequency of the tie-point power.

[0019] The control system 30 generates an operation command Z based on the operation plan X, the actual operation results Y2, the adjustment force command value Y3, and the adjustment force command value Y4. A known method is arbitrarily adopted for generating the operation command Z.

[0020] The operation plan X generated by the planning system 40 will be described in detail. As described above, the operation plan X specifies the planned value W SOC (i) [kWh] of the amount of power that the power storage device 21 should charge or discharge for each unit period. The planned value W SOC (i) is the amount of power of the power storage device 21 at the end of the unit period. Specifically, the planned value W SOC (i) is expressed by the following mathematical formula (1).

Equation

[0021] The symbol i in the mathematical formula (1) is a number for identifying the unit period, and the symbol T is the time length [hour] of the unit period. Also, the symbol Ps(i) in the mathematical formula (1) is the tie-point power [kW]. The tie-point power Ps(i) is expressed with a positive number for the discharging direction and a negative number for the charging direction. That is, a positive number of the tie-point power Ps(i) means the power value that the power storage system 20 should discharge to the power grid 10, and a negative number of the tie-point power Ps(i) means the power value that the power storage system 20 should charge by power supply from the power grid 10. The first line on the right side of the mathematical formula (1) is the planned value W SOC (i) when the power storage system 20 discharges, and the second line is the planned value W SOC (i) when the power storage system 20 charges.

[0022] The symbol η in the mathematical formula (1) out means the discharge efficiency of the power storage device 21. That is, the discharge efficiency η out means the ratio of the amount of power discharged by the power storage device 21 to the decrease in the amount of charge of the power storage device 21. Therefore, the lower the discharge efficiency η out , the smaller the amount of power that the power storage device 21 can discharge with respect to the decrease in the amount of charge. Also, the symbol η in the mathematical formula (1) in means the charge efficiency of the power storage device 21. That is, the charge efficiency ηin means the ratio of the amount of power actually charged by the power storage device 21 to the amount of power supplied to the power storage device 21. Therefore, the charging efficiency η in The lower it is, the smaller the amount of power that the power storage device 21 can charge with respect to the power supply amount.

[0023] In the formula (1), the operation of dividing the tie-point power Ps(i) by the discharge efficiency η out means the process of correcting the tie-point power Ps(i) by the discharge efficiency η out Similarly, in the formula (1), the operation of multiplying the tie-point power Ps(i) by the charging efficiency η in means the process of correcting the tie-point power Ps(i) by the charging efficiency η in As understood from the formula (1), the tie-point power Ps(i) is divided by the discharge efficiency η out or the charging efficiency η in to convert it into the amount of power within a unit period after correction, and the planned value W SOC (i - 1) in the immediately preceding unit period, the planned value W SOC (i) is calculated so that the difference therebetween is obtained.

[0024] For example, the tie-point power Ps(i) due to the regulating power such as the primary regulating power is uncertain until the regulating power command value Y4 is actually issued in the process of operating the power storage system 20. Therefore, in the first embodiment, as follows, the tie-point power Ps(i) is estimated using the expected value of the activation rate k(i).

[0025] First, the tie-point power Ps(i) is expressed by the following formula (2).

Equation

[0026] The planned power Pb(i) is a power value planned for each unit period according to the basic plan regarding the operation of the energy storage device 21. The basic plan that defines the planned power Pb(i) includes, for example, a power generation plan that defines a plan in the discharge direction (power generation direction) and a reference value plan that defines a plan in the charging direction (power consumption direction). As understood from the above description, the power exchanged between the energy storage system 20 and the power grid 10 is power with adjustment power such as primary regulation power superimposed on the basis of the planned power Pb(i).

[0027] The average charge-discharge power Pa(i) in Equation (2) is expressed by the following Equation (3).

Number

[0028] Therefore, in the actual operation process, when the adjustment power command value Y3 is maintained at the minimum value of 0, or when the adjustment power command value Y3 is maintained at the maximum value P ΔkW , it may occur. The activation rate k(i) in Equation (3) is the ratio (usage rate) of the predicted power consumption of the energy storage system 20 (or the actual power consumption of the energy storage system 20 according to the actual command) to the power amount [kWh] provided by the energy storage system 20 assuming that the maximum value P ΔkW command continues.

[0029] For example, the agreed power P ΔkWAssume a situation where the power is 5000 kW and the regulation power is provided for one unit period (30 minutes). When the regulation power command value Y3 in the first half of the unit period (starting point to 15 minutes) is 0 kW and the regulation power command value Y3 in the second half of the unit period (15 minutes to the end point) is 2500 kW, the activation rate k(i) becomes 25% through the following calculation.

Number

[0030] The activation rate k(i) described above is expressed by the following mathematical formula (4) including the first activation rate k1(i) and the second activation rate k2(i).

Number

[0031] The second activation rate k2(i) in the mathematical formula (4) is the ratio of the expected value of the regulation power command value Y3 to the contract power P ΔkW The second activation rate k2(i) is preset to a predetermined value. For example, the average value of the past activation rate k(i) is adopted as the second activation rate k2(i). Also, for example, a value predicted using artificial intelligence from the past operation results, or a value instructed by the administrator of the planning system 40 may be adopted as the second activation rate k2(i).

[0032] Note that since the frequency of the power in the power grid 10 (hereinafter referred to as "system frequency f") fluctuates around a predetermined reference frequency f0, during the supply of the primary regulation power, the charge command (negative number) and the discharge command (positive number) frequently switch. That is, the charge command and the discharge command cancel each other out. Therefore, when the regulation power supplied by the energy storage system 20 is only the primary regulation power, the second activation rate k2(i) may be set to zero.

[0033] The first activation rate k1(i) will be described in detail below. In the following description, the notation of the unit period number (i) is omitted for convenience.

[0034] First, focus on the adjustment force command value P1 of the primary adjustment force corresponding to the deviation of the system frequency f from the predetermined reference frequency f0 (hereinafter referred to as "frequency deviation") Δf. The reference frequency f0 is the reference value of the system frequency (60 Hz in western Japan, 50 Hz in eastern Japan). As illustrated in FIG. 2, the system frequency f frequently fluctuates around the reference frequency f0.

[0035] When the frequency deviation Δf reaches the maximum value (hereinafter referred to as "maximum frequency deviation") Δf max and considering that the supply of the agreed power P ΔkW is required, the adjustment force command value P1 is expressed by the following formula (5). Note that the maximum frequency deviation Δf max is a predetermined fixed value (for example, ±0.3 Hz or ±0.2 Hz). However, a variable value that changes under predetermined conditions may be adopted as the maximum frequency deviation Δf max . Note that the maximum frequency deviation Δf max may also be the upper limit value in the control of the frequency deviation Δf when changing the adjustment force command value P1 based on formula (5).

Equation

[0036] The frequency deviation Δf is calculated from the actual values observed in the past operation of the power system 10. For example, the frequency deviation Δf is calculated by statistically processing the past actual performance regarding the system frequency f. The frequency deviation Δf may be manually input by the administrator of the planning system 40, for example, by operating the operating device 44. Also, when the frequency deviation Δf is a numerical value for each unit period, the frequency deviation Δf for each unit period may be calculated from the measured values of the system frequency f in past unit periods with similar conditions in the unit period. The conditions of the unit period are, for example, meteorological information such as temperature, humidity, solar radiation amount, or weather.

[0037] As illustrated in FIG. 2, the average of the absolute value |Δf| of the frequency deviation Δf (hereinafter referred to as "average absolute deviation") Δf ave is assumed. The average absolute deviation Δf ave is applied as the frequency deviation Δf in Equation (5), and the average |P1| of the absolute value of the adjustment force command value P1 ave results in the following Equation (6).

Equation

[0038] Next, attention is paid to the average value P out_ave on the discharge side of the adjustment force command value P1 and the average value P in_ave on the charge side. The average value P out_ave on the discharge side is expressed by the following Equation (7), and the average value P in_ave on the charge side is expressed by the following Equation (8).

Equation

[0039] The symbol max(P1, 0) is an operator that selects the adjustment force command value P1 when the adjustment force command value P1 is positive (in the case of discharge) and selects 0 when the adjustment force command value P1 is negative. On the other hand, the symbol min(P1, 0) is an operator that selects the adjustment force command value P1 when the adjustment force command value P1 is negative (in the case of charge) and selects 0 when the adjustment force command value P1 is positive. Therefore, the following Equation (9) holds.

Equation

[0040] The average value |P1| of the absolute value |P1| of the adjustment force command value P1 in Equation (6) ave is expressed by the following Equation (10) by applying Equations (7) to (9).

Equation

[0041] Also, since the adjustment force command value P1 of the primary adjustment force fluctuates around 0, the average of the adjustment force command value P1 can be assumed to be 0. Therefore, the following mathematical formula (11) holds.

Number

[0042] From mathematical formulas (10) and (11) and the aforementioned mathematical formula (6), the following mathematical formula (12) is derived.

Number

[0043] Next, consider the charge and discharge losses due to the primary adjustment force. The amount of charge reduction ΔW out_ave [kWh] of the power corresponding to the average value P on the discharge side of the adjustment force command value P1 when the power storage device 21 discharges over a time period Δt is expressed by the following mathematical formula (13) using the discharge efficiency η SOC_out [kWh]. out is expressed by the following mathematical formula (13).

Number

Number

[0044] Therefore, the discharge loss ΔW loss_out of the power storage device 21 over a time period Δt is expressed by the following mathematical formula (15), and the charge loss ΔW loss_in of the power storage device 21 over a time period Δt is expressed by the following mathematical formula (16).

Number

Number

[0045] Therefore, the charge-discharge loss ΔW loss is expressed by the following mathematical formula (17).

Number

[0046] Charge-discharge loss ΔW loss To express the charge-discharge loss ΔW loss in terms of the activation rate k(i), it is necessary to convert the charge-discharge loss ΔW loss in the mathematical formula (17) into the command value of the adjustment force. Assuming that the charge-discharge loss ΔW loss in the mathematical formula (17) is the power lost due to the discharge of the power storage device 21, the discharge energy amount ΔW

Number

[0047] Converting the discharge energy amount ΔW loss ' in the mathematical formula (18) into the average power P loss during the time period Δt, it is expressed by the following mathematical formula (19).

Number

[0048] Since the first activation rate k1 is the conversion of the charge-discharge loss into an equivalent activation rate, the following mathematical formula (20) holds.

Number

[0049] From the mathematical formulas (19) and (20), the following mathematical formula (21) representing the first activation rate k1 is derived. The first activation rate k1 is a numerical value corresponding to the charge-discharge loss (P loss ) of the primary regulation force in the power storage device 21.

Number

[0050] Using the relationships described above, the specific configuration of the planning system 40 that generates the operation plan X will be described in detail below. FIG. 3 is a block diagram illustrating the configuration of the planning system 40. As illustrated in FIG. 3, the planning system 40 includes a control device 41, a storage device 42, a communication device 43, and an operation device 44. Note that the planning system 40 can be realized by a single device or by a plurality of devices separately configured from each other.

[0051] The control device 41 is composed of one or more processors that control each element of the planning system 40. Specifically, for example, the control device 41 is composed of one or more types of processors such as a PLD (Programmable Logic Device), a CPU (Central Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), or an ASIC (Application Specific Integrated Circuit).

[0052] The storage device 42 is one or more memories that store programs executed by the control device 41 and data used by the control device 41. The storage device 42 is composed of a known recording medium such as a magnetic recording medium or a semiconductor recording medium. The storage device 42 may be composed of a combination of multiple types of recording media. A portable recording medium that can be attached to and detached from the planning system 40 may be used as the storage device 42.

[0053] The communication device 43 communicates with external devices. For example, the communication device 43 communicates with each of the power storage system 20 (control device 41) and the planning system 40. The operation device 44 is an input device that receives instructions from the administrator of the planning system 40.

[0054] FIG. 4 is a block diagram illustrating a functional configuration of the planning system 40. The control device 41 realizes a plurality of functions (first calculation unit 51, second calculation unit 52, plan generation unit 53) for generating the operation plan X by executing a program stored in the storage device 42.

[0055] The first calculation unit 51 calculates the first activation rate k1(i) by performing the calculation of the mathematical formula (21). As understood from the mathematical formula (21), the first calculation unit 51 calculates the first activation rate k1(i) based on the charge efficiency η in and the discharge efficiency η out of the power storage device 21 and the frequency information regarding the system frequency f of the power system 10. The frequency information in the first embodiment is the average absolute deviation Δf that is the average of the absolute value |Δf| of the frequency deviation Δf, as understood from the mathematical formula (21). ave and the maximum frequency deviation Δf in the primary regulation force max and includes.

[0056] The second calculation unit 52 calculates the average charge / discharge power Pa(i) of the power storage device 21 based on the first activation rate k1(i) calculated by the first calculation unit 51. Specifically, the second calculation unit 52 calculates the activation rate k(i) by performing the calculation of the mathematical formula (4) to which the first activation rate k1(i) is applied, and calculates the average charge / discharge power Pa(i) by performing the calculation of the mathematical formula (3) to which the activation rate k(i) is applied. As understood from the mathematical formula (3), the second calculation unit 52 calculates the average charge / discharge power Pa(i) of the power storage device 21 based on the committed power P of the regulation force ΔkW and the first activation rate k1(i).

[0057] The plan generation unit 53 generates an operation plan X for the power storage device 21 based on the average charge / discharge power Pa(i) calculated by the second calculation unit 52. Specifically, the plan generation unit 53 calculates the tie-point power Ps(i) by performing the calculation of the mathematical formula (2) to which the average charge / discharge power Pa(i) and the planned power Pb(i) other than the regulation force are applied, and calculates the planned value W of the amount of power that the power storage device 21 should charge or discharge by performing the calculation of the mathematical formula (1) to which the tie-point power Ps(i) is applied. SOC(i) is calculated. By repeating the above processing for each unit period within a predetermined period on the time axis (for example, one day), the planned value W for different unit periods SOC An operation plan X that specifies (i) is generated.

[0058] As described above, in the first embodiment, in addition to the frequency information regarding the system frequency f, the charging efficiency η of the power storage device 21 in and the discharging efficiency η out are taken into account in the average charge-discharge power Pa(i) of the power storage device 21. Therefore, compared with the form of generating the operation plan X based only on the frequency information, an appropriate operation plan X considering the decrease in the charge amount of the power storage device 21 can be generated.

[0059] Also, the frequency information in the first embodiment is the average absolute deviation Δf that is the average of the absolute value |Δf| of the frequency deviation Δf ave Since it includes, the operation plan X can be appropriately calculated compared with the form in which the frequency information does not include the average absolute deviation Δf ave .

[0060] B: Second Embodiment The second embodiment of the present disclosure will be described. For elements whose functions are the same as those in the first embodiment in each aspect exemplified below, the same reference numerals as those in the description of the first embodiment are used, and the detailed description of each is appropriately omitted.

[0061] FIG. 5 is a block diagram illustrating a functional configuration of the planning system 40 in the second embodiment. As illustrated in FIG. 5, the control device 41 of the second embodiment functions also as a coefficient setting unit 54 in addition to the same elements as those in the first embodiment (the first calculation unit 51, the second calculation unit 52, and the plan generation unit 53).

[0062] The coefficient setting unit 54 sets the calculation coefficient α applied to the above-described mathematical formula (4). As described above, the calculation coefficient α is a coefficient representing the degree of influence of the first activation rate k1(i) on the operation plan X. The coefficient setting unit 54 sets the calculation coefficient α according to various factors. For example, the coefficient setting unit 54 sets the calculation coefficient α according to an operation from the administrator to the operation device 44.

[0063] Similar to the first embodiment, the second calculation unit 52 calculates the average charge-discharge power Pa(i) of the power storage device 21 based on the first activation rate k1(i). For the calculation of the mathematical formula (4) in which the second calculation unit 52 calculates the activation rate k(i) corresponding to the first activation rate k1(i), the calculation coefficient α set by the coefficient setting unit 54 is applied. As described above, the second calculation unit 52 of the second embodiment is the contract power P ΔkW And based on the first activation rate k1(i) and the calculation coefficient α set by the coefficient setting unit 54, the average charge-discharge power Pa(i) is calculated. The configurations and operations of the first calculation unit 51 and the plan generation unit 53 are the same as those of the first embodiment.

[0064] In the second embodiment, the same effects as those of the first embodiment are also achieved. Also, in the second embodiment, the contract power P ΔkW Based on the first activation rate k1(i) and the calculation coefficient α, the average charge-discharge power Pa(i) is calculated. Therefore, an appropriate operation plan X can be generated according to various situations, such as the power supply situation by the power storage device 21.

[0065] C: Third Embodiment The functional configuration of the plan system 40 of the third embodiment is the same as that of the second embodiment illustrated in FIG. 5. That is, the coefficient setting unit 54 variably sets the calculation coefficient α. The coefficient setting unit 54 of the third embodiment is the power offset P according to the basic plan regarding the operation of the power storage device 21 offset Based on this, the calculation coefficient α is set.

[0066] Power offset P offset Is the deviation (DC component) of the power that the power storage device 21 should charge and discharge. Specifically, the power offset P offset Is expressed by the following mathematical formula (22).

Equation

[0067] The planned power Pb in formula (22) is the power (power other than regulation power) planned for each unit period according to the basic plan as described above. As understood from formula (22), the coefficient setting unit 54 of the third embodiment applies the planned power Pb(i) defined by the basic plan, the agreed power P of the regulation power, and the second activation rate k2(i) to calculate the power offset P ΔkW by the operation of formula (22), and sets the operation coefficient α according to the power offset P offset . offset

[0068] FIG. 6 is a graph showing the relationship between the power offset P offset and the operation coefficient α. FIG. 7 is an explanatory diagram of the operation in which the coefficient setting unit 54 of the third embodiment sets the operation coefficient α. As described above, the regulation power command value P1 of the primary regulation power frequently fluctuates around 0. In the third embodiment, it is assumed that the regulation power command value P1 fluctuates within the range between the minimum value (hereinafter referred to as "regulation power lower limit value") -ΔP1 and the maximum value (hereinafter referred to as "regulation power upper limit value") +ΔP1. As illustrated in FIG. 7, the tie-point power Ps(i) frequently fluctuates due to the primary regulation power. The power offset P offset is the power corresponding to the center of fluctuation of the tie-point power Ps(i).

[0069] When the power offset P offset is 0, it means that the tie-point power Ps(i) is composed only of the primary regulation power and the planned power Pb is 0. Therefore, when the power offset P offset is 0, the coefficient setting unit 54 sets the operation coefficient to 1 (i.e., the maximum value).

[0070] When the power offset P offset is less than the regulation power lower limit value -ΔP1, the tie-point power Ps(i) becomes only a negative number indicating charging of the energy storage device 21. On the other hand, when the power offset P offset exceeds the regulation power upper limit value +ΔP1, the tie-point power Ps(i) becomes only a positive number indicating discharging of the energy storage device 21. That is, the absolute value |P offset of the power offset P offset ​When | exceeds the predetermined value ΔP1, the switching between charging and discharging in the power storage device 21 does not occur. Therefore, the power offset P offset When is below the adjustment force lower limit value -ΔP1 or above the adjustment force upper limit value +ΔP1, the coefficient setting unit 54 sets the calculation coefficient α to 0. That is, the influence of the first activation rate k1(i) on the operation plan X is ignored.

[0071] On the other hand, the power offset P offset When is a numerical value between the adjustment force lower limit value -ΔP1 and the adjustment force upper limit value +ΔP1, although the switching frequency in the power storage device 21 decreases according to the power offset P offset the switching between charging and discharging in the power storage device 21 occurs. Therefore, when the power offset P offset is a numerical value between the adjustment force lower limit value -ΔP1 and the adjustment force upper limit value +ΔP1, the coefficient setting unit 54 sets the calculation coefficient α to a variable value according to the power offset P offset That is, the calculation coefficient α is expressed by a function F(P offset ) with P offset as a variable.

[0072] Specifically, when the power offset P offset is a negative number greater than or equal to the adjustment force lower limit value -ΔP1 (-P1 ≤ P offset < 0), the coefficient setting unit 54 sets the calculation coefficient α so that the calculation coefficient α increases (for example, monotonically increases) in conjunction with the increase in the power offset P offset Specifically, the calculation coefficient α changes linearly with respect to the power offset P offset On the other hand, when the power offset P offset is a positive number less than or equal to the adjustment force upper limit value +ΔP1 (0 < P offset ≤ +ΔP1), the coefficient setting unit 54 sets the calculation coefficient α so that the calculation coefficient α decreases (for example, monotonically decreases) in conjunction with the increase in the power offset P offset Specifically, the calculation coefficient α changes linearly with respect to the power offset P offset Note that the relationship between the calculation coefficient α with respect to the power offset P offset is not limited to the relationship illustrated in FIG. 6. For example, the calculation coefficient α may be related to the power offset P offsetIt may change curvilinearly with respect to

[0073] As understood from the above description, the operation coefficient α in the third embodiment is expressed by the following mathematical formula (23).

Equation

[0074] The configurations and operations of the first operation unit 51 and the plan generation unit 53 are the same as those in the first embodiment. Therefore, the same effects as those in the first embodiment are also achieved in the third embodiment. Also, in the third embodiment, the operation coefficient α is set based on the power offset P offset by the basic plan (power generation plan or reference value plan). Therefore, considering the tendency that it becomes difficult for the charging and discharging switching in the power storage device 21 to occur according to the power offset P offset (the decrease in the charge amount due to the charge and discharge loss is less likely to occur), an appropriate operation plan X can be generated.

[0075] D: Fourth Embodiment FIG. 8 is a block diagram illustrating the functional configuration of the plan system 40 in the fourth embodiment. As illustrated in FIG. 8, the control device 41 of the second embodiment functions also as a third operation unit 55 in addition to the same elements (the first operation unit 51, the second operation unit 52, the plan generation unit 53) as those in the first embodiment.

[0076] The third operation unit 55 calculates a third activation rate k3. The third activation rate k3 corresponds to the discharge loss when the power storage device 21 does not correspond to the command value in the charging direction among the adjustment force command values P1 (that is, when the power storage device 21 performs only discharging). Specifically, the average value P out_ave (mathematical formula (12)) on the discharge side of the adjustment force command value P1, the contract power P ΔkW and the third activation rate k3 satisfy the following relationship of mathematical formula (24).

Equation

[0077] When the formula (24) is transformed using the formula (12), the following formula (25) is derived. The third calculation unit 55 calculates the third activation rate k3 by the calculation of the formula (25).

Number

[0078] The second calculation unit 52 of the fourth embodiment calculates the activation rate k by the calculation of the following formula (26) instead of the formula (4) of the first embodiment.

Number

[0079] The selection coefficient b and the selection coefficient c in the formula (26) are set to either 0 or 1. The selection coefficient b and the selection coefficient c are set complementarily. That is, when the selection coefficient b is set to 0, the selection coefficient c is set to 1, and when the selection coefficient b is set to 1, the selection coefficient c is set to 0. Therefore, the second calculation unit 52 selects one of the first activation rate k1 and the third activation rate k3. Specifically, the second calculation unit 52 selects the first activation rate k1 by setting the selection coefficient b to 1, and selects the third activation rate k3 by setting the selection coefficient c to 1.

[0080] Specifically, when the power storage device 21 does not execute charging, the second calculation unit 52 selects the third activation rate k3 by setting the selection coefficient b to 0 and the selection coefficient c to 1. On the other hand, when the power storage device 21 executes both charging and discharging, the second calculation unit 52 selects the first activation rate k1 by setting the selection coefficient b to 1 and the selection coefficient c to 0. The case where the power storage device 21 does not execute charging is, for example, a state where the power storage device 21 cannot execute further charging because the charge rate (SOC) has reached the upper limit value.

[0081] The second calculation unit 52 identifies the charging rate of the power storage device 21 by referring to the operation record Y2 supplied from the power storage system 20 via the control system 30, and selects the third activation rate k3 when the charging rate has reached a predetermined upper limit value. On the other hand, when the charging rate of the power storage device 21 has not reached the upper limit value (that is, when the power storage device 21 can perform both charging and discharging), the second calculation unit 52 selects the first activation rate k1. Note that the second calculation unit 52 may select one of the first activation rate k1 and the third activation rate k3 according to an operation on the operation device 44 by the administrator of the planning system 40.

[0082] The second calculation unit 52 calculates the activation rate k based on the selected value among the first activation rate k1 and the third activation rate k3 and the second activation rate k2 as shown in formula (26). Further, the second calculation unit 52 calculates the average charge / discharge power Pa(i) by the calculation of formula (3) applied with the activation rate k and the contract power P ΔkW As understood from the above description, the second calculation unit 52 of the fourth embodiment calculates the average charge / discharge power Pa(i) based on the contract power P ΔkW and one of the first activation rate k1 and the third activation rate k3.

[0083] In the fourth embodiment, the same effects as those of the first embodiment are achieved. Further, in the fourth embodiment, even in a situation where the power storage device 21 only discharges and does not charge, the operation plan X of the power storage device 21 can be appropriately generated. The configurations of the second or third embodiment in which the coefficient setting unit 54 sets the calculation coefficient α may be similarly applied in the fourth embodiment.

[0084] In the above description, the case where the charging rate of the power storage device 21 has reached the upper limit value is exemplified, but when the power storage device 21 does not perform charging, it is not limited to the above example. For example, there may be an operation in which the power storage device 21 is not made to charge when the overall profit of the power system 100 is greater when the power storage device 21 does not respond to the command value in the charging direction among the adjustment force command values P1.

[0085] In the above description, the case where the power storage device 21 only performs discharging and does not perform charging has been exemplified. However, the same form is also applicable to the case where the power storage device 21 only performs charging and does not perform discharging. In the form where the power storage device 21 only performs charging, the third activation rate k3 corresponds to the charging loss when the power storage device 21 does not correspond to the command value in the discharging direction among the adjustment force command values P1 (that is, when the power storage device 21 only performs charging). As understood from the above description, the third activation rate k3 is comprehensively expressed as a numerical value corresponding to the loss (charging loss or discharging loss) when the power storage device 21 does not correspond to either charging or discharging in the primary adjustment force. Note that the operation of the second calculation unit 52 when the power storage device 21 does not correspond to the command value in the discharging direction among the adjustment force command values P1 is the same as that in the fourth embodiment.

[0086] E: Fifth Embodiment The frequency information applied by the first calculation unit 51 of the first embodiment to calculate the first activation rate k1(i) is, as shown in Equation (21), the mean absolute deviation Δf ave and the maximum frequency deviation Δf max and includes. In the fifth embodiment, the content of the frequency information is different from that in the first embodiment.

[0087] The frequency deviation Δf is the deviation of the system frequency f from the reference frequency f0. In the fifth embodiment, attention is paid to the standard deviation Δf σ of the frequency deviation Δf. Regarding the mean absolute deviation Δf ave and the standard deviation Δf σ the following relationship of Equation (27) holds.

Equation

[0088] By substituting Equation (27) into Equation (21), the following Equation (28) representing the first activation rate k1 is derived.

Equation

[0089] The first calculation unit 51 of the fifth embodiment calculates the first activation rate k1(i) by performing the calculation of the mathematical formula (28). As understood from the mathematical formula (28), the first calculation unit 51 calculates the charging efficiency η in and the discharging efficiency η out of the power storage device 21, and calculates the first activation rate k1(i) based on the frequency information regarding the system frequency f of the power grid 10. The frequency information in the fifth embodiment is, as understood from the mathematical formula (28), the standard deviation Δf of the frequency deviation Δf σ and the maximum frequency deviation Δf in the primary frequency regulation force max . That is, the fifth embodiment calculates the first activation rate k1(i) using the standard deviation Δf of the frequency deviation Δf ave instead of the average absolute deviation Δf in the first embodiment σ .

[0090] Even in the fifth embodiment, the same effects as those in the first embodiment are achieved. Also, the frequency information in the fifth embodiment includes the standard deviation Δf of the frequency deviation Δf σ . Therefore, even in a situation where the average absolute deviation Δf of the system frequency f cannot be obtained ave , the first activation rate k1(i) can be appropriately calculated. Note that the configuration of the fifth embodiment in which the frequency information includes the standard deviation Δf σ may be applied to any of the first to fourth embodiments

[0091] The average absolute deviation Δf in the first embodiment ave and the standard deviation Δf in the fifth embodiment σ are comprehensively expressed as statistical quantities (dispersion degrees) representing the degree of dispersion of the frequency deviation Δf of the system frequency f with respect to the reference frequency f0. That is, the frequency information used for calculating the first activation rate k1(i) includes the dispersion degree of the frequency deviation Δf and the maximum frequency deviation Δf max . According to the above configuration, the first activation rate k1(i) can be appropriately calculated based on the dispersion degree of the frequency deviation Δf and the maximum frequency deviation Δf max .

[0092] Note that the description "the nth" (where n is a natural number) in this application is used only as a formal and convenient label for distinguishing each element in notation and has no substantial meaning. Therefore, there is no room for limited interpretation of the position or order of each element based on the notation "the nth".

[0093] G: Supplementary Note From the forms exemplified above, for example, the following configuration can be grasped.

[0094] A planning system according to one aspect (Aspect 1) of the present disclosure is a planning system that generates an operation plan regarding charging and discharging of a power storage device capable of providing primary regulation power to a power system. The planning system includes a first calculation unit that calculates a first activation rate corresponding to the loss due to charging and discharging of the primary regulation power based on the charging efficiency and discharging efficiency of the power storage device and frequency information regarding the system frequency in the power system, a second calculation unit that calculates the average charging and discharging power of the power storage device based on the contract power of the regulation power and the first activation rate, and a plan generation unit that generates the operation plan based on the average charging and discharging power. In the above aspect, in addition to the frequency information regarding the system frequency, the charging efficiency and discharging efficiency of the power storage device are taken into account in the average charging and discharging power of the power storage device. Therefore, compared with the form of generating an operation plan based only on frequency information, an appropriate operation plan considering the reduction amount of the charge amount of the power storage device can be generated.

[0095] In a specific example of Aspect 1 (Aspect 2), the frequency information includes the spread of the deviation of the system frequency with respect to a predetermined reference frequency and the maximum frequency deviation in the primary regulation power. In the above aspect, the first activation rate can be appropriately calculated based on the spread of the system frequency and the maximum frequency deviation.

[0096] In a specific example of Aspect 2 (Aspect 3), the spread is the average of the absolute values of the deviations of the system frequency with respect to the reference frequency. In the above aspect, the first activation rate can be appropriately calculated using the average of the absolute values of the deviations of the system frequency with respect to the reference frequency (mean absolute deviation).

[0097]

[0097] In the specific example of Mode 2 (Mode 4), the spread is the standard deviation of the deviation of the system frequency with respect to the reference frequency. In the above aspects, by using the standard deviation of the deviation of the system frequency with respect to the reference frequency, the first activation rate can be appropriately calculated even in a situation where the average absolute deviation of the system frequency cannot be obtained.

[0098] In a specific example of any one of Modes 1 to 4 (Mode 5), the apparatus further includes a coefficient setting unit that sets an arithmetic coefficient representing the degree of influence of the first activation rate on the operation plan, and the second arithmetic unit calculates the average charge / discharge power based on the contract power, the first activation rate, and the arithmetic coefficient. In the above aspects, since the average charge / discharge power is calculated based on the contract power, the first activation rate, and the arithmetic coefficient, an appropriate operation plan can be generated according to various situations such as the power supply situation by the power storage device.

[0099] In the specific example of Mode 5 (Mode 6), the coefficient setting unit sets the arithmetic coefficient based on a power offset according to a basic plan regarding the operation of the power storage device. In the above aspects, since the arithmetic coefficient is set based on the power offset by the basic plan (power generation plan or reference value plan), an appropriate operation plan can be generated in consideration of the tendency that it becomes difficult for the charging and discharging switching in the power storage device to occur according to the power offset (it becomes difficult for the decrease in the charged amount due to the charge / discharge loss to occur).

[0100] In a specific example of any one of Modes 1 to 6 (Mode 7), the apparatus further includes a third arithmetic unit that calculates a third activation rate corresponding to the loss when the power storage device does not correspond to either charging or discharging in the primary regulation power, and the second arithmetic unit calculates the average charge / discharge power based on the contract power and one of the first activation rate and the third activation rate. In the above aspects, even in a situation where the power storage device performs only one of charging and discharging, an appropriate operation plan for the power storage device can be generated.

[0101] A planning method according to one aspect (Aspect 8) of the present disclosure is a planning method for generating an operation plan regarding charging and discharging of a power storage device capable of providing primary regulation power to a power system. The planning system calculates a first activation rate corresponding to the loss due to charging and discharging of the primary regulation power based on the charging efficiency and discharging efficiency of the power storage device and frequency information regarding the system frequency in the power system, calculates the average charging and discharging power of the power storage device based on the contracted power of the regulation power and the first activation rate, and generates the operation plan based on the average charging and discharging power.

Explanation of Signs

[0102] 100…Power system, 10…Power system, 11…Interconnection point, 20…Power storage system, 21…Power storage device, 22…Control device, 30…Control system, 40…Planning system, 41…Control device, 42…Storage device, 43…Communication device, 44…Operating device, 51…First calculation unit, 52…Second calculation unit, 53…Plan generation unit, 54…Coefficient setting unit, 55…Third calculation unit.

Claims

1. A planning system that generates an operation plan for charging and discharging a power storage device that can provide a primary control reserve to a power grid, a first calculation unit that calculates a first activation rate corresponding to a loss due to charging and discharging of the primary control capacity based on a charging efficiency and a discharging efficiency of the power storage device and frequency information related to a system frequency in the power system; A second calculation unit that calculates an average charge / discharge power of the power storage device based on an agreed power of adjustment capacity and the first activation rate; a plan generating unit that generates the operation plan based on the average charge / discharge power; A planning system comprising:

2. The frequency information is A degree of dispersion of the deviation of the system frequency from a predetermined reference frequency; and and a maximum frequency deviation in the primary control capability. The planning system of claim 1.

3. The dispersion degree is is the average of the absolute values ​​of the deviation of the system frequency from the reference frequency. The planning system of claim 2.

4. The dispersion degree is is the standard deviation of the deviation of the system frequency from the reference frequency. The planning system of claim 2.

5. a coefficient setting unit that sets a calculation coefficient that indicates a degree of influence of the first activation rate on the operation plan, The second calculation unit calculates the average charge / discharge power based on the contract power, the first activation rate, and the calculation coefficient. The planning system of claim 1.

6. The coefficient setting unit sets the calculation coefficient based on a power offset according to a basic plan for the operation of the power storage device. The planning system of claim 5.

7. A third calculation unit is further provided to calculate a third activation rate corresponding to a loss when the power storage device does not respond to one of charging and discharging in the primary control capacity, The second calculation unit calculates the average charge / discharge power based on the contract power and one of the first activation rate and the third activation rate. The planning system of claim 1.

8. A planning method for generating an operation plan for charging and discharging a power storage device capable of providing a primary control reserve to a power grid, comprising: The planning system Calculating a first activation rate corresponding to a loss due to charging and discharging of the primary control reserve based on a charging efficiency and a discharging efficiency of the power storage device and frequency information related to a system frequency in the power system; Calculating an average charge / discharge power of the power storage device based on an agreed power of adjustment capacity and the first activation rate; generating the operation plan based on the average charge / discharge power; Planning methods including:

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