Creation method of operation plan for storage battery and operation plan creation support device

Abstract

A creation method of an operation plan for a storage battery disclosed herein includes: an output section setting step of selectively setting each of a plurality of unit time sections to one of a first unit time section, in which a charge / discharge output is made constant, or a second unit time section, in which the charge / discharge output is varied; and a variation pattern setting step for setting variation patterns of the charge / discharge outputs in the second unit time section, by setting an output ratio which is the ratio of the charge / discharge output to a reference output, for each of a plurality of pattern setting units obtained by dividing the unit time sections at predetermined time intervals. In the variation pattern setting step, a reference value for a predetermined setting index selected in advance is calculated from charge / discharge output result values for past charging / discharging operations having a common use with the second unit time sections subject to the variation pattern setting, and the output ratios for the variation patterns are set so that an index value, which is the value of the setting index for the variation patterns, satisfies a predetermined condition based on the reference value.

Description

Battery operation plan creation method and operation plan creation support device

[0001] The present invention relates to the creation of an operation plan for a storage battery, and in particular to the creation of an operation plan for an application in which the operation output is not determined at the time of creation of the operation plan.

[0002] Energy storage systems equipped with storage batteries such as sodium-sulfur batteries (NaS batteries) and lithium-ion batteries are primarily used for adjusting the supply and demand of electricity (power storage compensation), but in recent years they have also begun to be used for trading electricity for monetization in electricity markets (e.g., wholesale electricity markets, capacity markets, and supply and demand adjustment markets).

[0003] For example, a guidance device for efficiently operating an NaS battery used in combination with a power generation device whose output fluctuates is already known (see, for example, Patent Document 1). Patent Document 1 discloses an example in which an NaS battery is applied to a power storage compensation device for load leveling, a power storage compensation device used in combination with wind power generation, etc.

[0004] Patent Document 1 also discloses a method for calculating battery temperature and remaining capacity (SOC) executed by a guidance device. In Patent Document 1, the SOC is calculated at predetermined time intervals Δt. Specifically, the SOC(n) at the time when the nth time interval Δt has elapsed is calculated using the formula "SOC(n-1) - discharge current In x unit time Δt."

[0005] A control device that controls a plurality of power storage systems that charge and discharge in accordance with an energy service is also known (see, for example, Patent Document 2). The control device disclosed in Patent Document 2 calculates a plan for charging and discharging the power storage systems connected to a power grid, and determines a remaining charge change model based on a maximum charging and discharging output in accordance with the energy service and an actual change in the remaining charge.

[0006] Examples of energy services include frequency regulation services such as governor-free and load frequency control.

[0007] However, when a storage battery is to be operated for a supply and demand balancing market that targets frequency adjustment and supply and demand adjustment, which are envisioned as energy services in Patent Document 2, the operational output (charge and discharge output) is not determined at the time of creating the operation plan in advance. Therefore, depending on how the operation plan is created, it may not actually be possible to operate in the supply and demand balancing market, or the operation may be too lenient for the performance of the power storage system, but a technology for creating an operation plan that is suitable for such a supply and demand balancing market has not yet been established.

[0008] For example, Patent Document 1 discloses a method for planning the charging and discharging of a storage battery according to a predicted value of the amount of power generated in renewable energy power generation in order to compensate for output fluctuations in renewable energy power generation, but does not disclose anything about application to frequency adjustment or supply and demand adjustment.

[0009] Furthermore, in the technology disclosed in Patent Document 2, there are cases where the calculated charge / discharge plan cannot be executed due to constraints other than the remaining dischargeable capacity of the storage battery, such as the temperature of the storage battery.

[0010] If a charging / discharging plan that was judged to be feasible cannot actually be implemented, the battery operator may be required to pay a penalty to the person who is the subject of the charging / discharging, such as the operator of a grid power system.

[0011] On the other hand, if a battery operator changes its charging / discharging plan to one that has a margin for the battery's performance by reducing the amount of charging / discharging because it is predicted that the plan cannot be implemented, but the operating plan before the change is actually implemented, the battery operator will miss out on profits that they would have otherwise gained.

[0012] JP 2008-210586 A Japanese Patent No. 7001152 A

[0013] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for suitably creating an operation plan for a storage battery that is unlikely to be unable to charge or discharge during actual operation, even when the storage battery is used for an application in which the operational output is not determined in advance.

[0014] In order to solve the above problem, a first aspect of the present invention is a method for creating an operation plan for a storage battery, in which set values ​​of charge and discharge outputs for a predetermined period are described for each unit time segment, the method comprising: an output segment setting step for selectively setting each of a plurality of unit time segments to either a first unit time segment in which the charge and discharge output is constant or a second unit time segment in which the charge and discharge output is varied; and a variation pattern setting step for setting an output ratio, which is the ratio of the charge and discharge output to a reference output, for each of a plurality of pattern setting units obtained by dividing the unit time segment at predetermined time intervals, thereby setting a variation pattern of the charge and discharge output in the second unit time segment. In the variation pattern setting step, a reference value for a predetermined setting index selected in advance is calculated from actual charge and discharge output values ​​for past charge and discharge operations that have a common use with the second unit time segment for which the variation pattern is set, and the output ratio for the variation pattern is set so that an index value, which is the value of the set index for the variation pattern, satisfies a predetermined condition based on the reference value.

[0015] A second aspect of the present invention is a method for creating an operation plan for a storage battery according to the first aspect, wherein the length of the unit time section is T, the predetermined time increment is Δt, the output ratio in the pattern setting unit for n, n = 1 to T / Δt, is Rn(n), and k is a natural number, and the predetermined setting index is: setting index (a): total discharge output ratio = Σ(Rn(n)), where Rn(n) > 0, setting index (b): total charge output ratio = Σ(-Rn(n)), where Rn(n) <0, set index (c): total operational output ratio = total discharge output ratio + total charge output ratio, set index (d): actual discharge output ratio = total discharge output ratio - total charge output ratio, set index (e): actual charge output ratio = total charge output ratio - total discharge output ratio, set index (f): maximum cumulative output ratio = maximum value of Σ(Rn(k)) (k = 1 to n) for all n, set index (g): minimum cumulative output ratio = minimum value of Σ(Rn(k)) (k = 1 to n) for all n.

[0016] A third aspect of the present invention is a method for creating an operation plan for a storage battery according to the second aspect, characterized in that the reference value is set to the average value of calculated values ​​calculated from the actual charge / discharge output values ​​for a plurality of past charge / discharge operations for each of the setting indicators (a) to (g).

[0017] A fourth aspect of the present invention is a method for creating an operation plan for a storage battery according to the second or third aspect, characterized in that in the fluctuation pattern setting process, the output ratio is set so that the index value for at least one of the setting indicators (a) to (g) matches the reference value.

[0018] A fifth aspect of the present invention is a method for creating an operation plan for a storage battery according to the third aspect, characterized in that in the fluctuation pattern setting step, the fluctuation pattern is set so that at least one of the remaining capacity and temperature of the storage battery approaches the upper or lower limit of the allowable range compared to when the index value for at least one of the setting indexes (a) to (g) is set to match the average value.

[0019] A sixth aspect of the present invention is a method for creating an operation plan for a storage battery according to the first aspect, further comprising: a simulation step for performing a simulation of the remaining capacity and temperature of the storage battery when the storage battery is caused to perform charging and discharging operations based on the created operation plan for each of the plurality of unit time segments; and a determination step for determining whether the operation plan can be adopted based on the results of the simulation, wherein in the determination step, if the remaining capacity and the temperature obtained by the simulation are within an allowable range for all of the plurality of unit time segments, it is determined that the operation plan can be adopted.

[0020] A seventh aspect of the present invention is a method for creating an operation plan for a storage battery according to the sixth aspect, characterized in that in the judgment step, for the first unit time segment, it is judged that operation in accordance with the operation plan is possible for the unit time segment if the remaining capacity and the temperature at the end of the unit time segment are within an acceptable range, and for the second unit time segment, it is judged that operation in accordance with the operation plan is possible for the unit time segment if the remaining capacity and the temperature for each pattern setting unit are all within an acceptable range, and when it is judged that operation is possible for all of the plurality of unit time segments, it is judged that the operation plan is adoptable.

[0021] An eighth aspect of the present invention is a method for creating an operation plan for a battery according to the sixth aspect, further comprising a realization accuracy calculation step of calculating a realization accuracy of the operation plan, wherein the realization accuracy is the product of a temperature coefficient STemp, which is set to a value closer to 0 the closer the maximum temperature value of the battery at each time interval is to an upper temperature limit, and is set to a value closer to 1 the farther it is from the upper temperature limit; a capacity upper limit coefficient SSocUL, which is set to a value closer to 0 the closer the maximum remaining capacity value at each time interval is to a capacity upper limit, and is set to a value closer to 1 the farther it is from the capacity upper limit; and a capacity lower limit coefficient SSocLL, which is set to a value closer to 0 the closer the minimum remaining capacity value at each time interval is to a lower capacity limit, and is set to a value closer to 1 the farther it is from the capacity lower limit.

[0022] A ninth aspect of the present invention is an apparatus for assisting in the creation of an operation plan for a storage battery, in which set values ​​of charge and discharge outputs for a predetermined period are described for each unit time segment, the apparatus comprising: an output segment setting means for enabling each of a plurality of unit time segments to be selectively set to either a first unit time segment in which the charge and discharge output is constant or a second unit time segment in which the charge and discharge output is varied; and a fluctuation pattern setting means for enabling the setting of a fluctuation pattern of the charge and discharge output in the second unit time segment by setting an output ratio, which is the ratio of the charge and discharge output to a reference output, for each of a plurality of pattern setting units obtained by dividing the unit time segment at predetermined time intervals, the fluctuation pattern setting means calculating a reference value for a predetermined setting index selected in advance from actual charge and discharge output values ​​for past charge and discharge operations that have a common use with the second unit time segment for which the fluctuation pattern is set, and is also capable of calculating an index value, which is the value of the setting index for the fluctuation pattern, and in creating the fluctuation pattern, it is possible to set the output ratio such that the index value satisfies a predetermined condition based on the reference value.

[0023] A tenth aspect of the present invention is the storage battery operation plan creation support device according to the ninth aspect, wherein, when the length of the unit time section is T, the predetermined time interval is Δt, the output ratio in the pattern setting unit for n, n = 1 to T / Δt, is Rn(n), and k is a natural number, the predetermined setting index is: setting index (a): total discharge output ratio = Σ(Rn(n)), where Rn(n) > 0, setting index (b): total charge output ratio = Σ(-Rn(n)), where Rn(n ) < 0, set index (c): total operational output ratio = total discharge output ratio + total charge output ratio, set index (d): actual discharge output ratio = total discharge output ratio - total charge output ratio, set index (e): actual charge output ratio = total charge output ratio - total discharge output ratio, set index (f): maximum cumulative output ratio = maximum value of Σ(Rn(k)) (k = 1 to n) for all n, set index (g): minimum cumulative output ratio = minimum value of Σ(Rn(k)) (k = 1 to n) for all n.

[0024] An eleventh aspect of the present invention is a battery operation plan creation support device relating to the tenth aspect, characterized in that the reference value is an average value of calculated values ​​calculated from the actual charge / discharge output values ​​for multiple past charge / discharge operations for each of the setting indicators (a) to (g).

[0025] A twelfth aspect of the present invention is a storage battery operation plan creation support device relating to any of the ninth to eleventh aspects, further comprising: a simulation means for performing a simulation of the remaining capacity and temperature of the storage battery when the storage battery is caused to perform charging and discharging operations based on the created operation plan for each of the plurality of unit time segments; and a determination means for determining whether the operation plan can be adopted based on the results of the simulation, wherein the determination means determines that the operation plan can be adopted if the remaining capacity and the temperature obtained by the simulation for all of the plurality of unit time segments are within an allowable range.

[0026] A thirteenth aspect of the present invention is an operation plan creation device for a storage battery according to the twelfth aspect, characterized in that the determination means determines that operation in accordance with the operation plan is possible for the first unit time segment if the remaining capacity and the temperature at the end of the unit time segment are within an acceptable range, determines that operation in accordance with the operation plan is possible for the second unit time segment if the remaining capacity and the temperature for each pattern setting unit are all within an acceptable range, and determines that the operation plan is adoptable if it is determined that operation is possible for all of the plurality of unit time segments.

[0027] A fourteenth aspect of the present invention is a storage battery operation plan creation support device according to the twelfth aspect, further comprising a realization accuracy calculation means for calculating a realization accuracy of the operation plan, wherein the realization accuracy is the product of a temperature coefficient STemp, which is set to a value closer to 0 the closer the maximum temperature value of the storage battery at each time interval is to an upper temperature limit, and is set to a value closer to 1 the farther it is from the upper temperature limit; a capacity upper limit coefficient SSocUL, which is set to a value closer to 0 the closer the maximum remaining capacity value at each time interval is to a capacity upper limit, and is set to a value closer to 1 the farther it is from the capacity upper limit; and a capacity lower limit coefficient SSocLL, which is set to a value closer to 0 the closer the minimum remaining capacity value at each time interval is to a lower capacity limit, and is set to a value closer to 1 the farther it is from the capacity lower limit.

[0028] According to the first to fourteenth aspects of the present invention, when creating an operation plan for a storage battery, even if it is necessary to vary the operation output of some of the unit time segments in the operation plan for purposes such as bidding in a supply and demand adjustment market, and the variation in the actual operation output is not determined in advance, it is possible to reduce the possibility that the storage battery will become unable to operate due to the actual charging and discharging operation differing from the plan.

[0029] 1 is a diagram showing a schematic configuration of a battery system 100. FIG. 1 is a block diagram showing functional components of a battery control device 10 and an operation guidance device 11. FIG. 2 is a diagram showing, in tabular form, an operation plan created in the operation guidance device 11. FIG. 3 is a diagram showing, in tabular form, the setting contents of the fluctuation pattern of a frame whose output classification is set to "Fluctuation 1" in column R3 of FIG. 3. FIG. 4 is a diagram illustrating an example of a fluctuation pattern of operation output in a certain unit time segment. FIG. 5 is a diagram showing the flow of a simulation. FIG. 6 is a diagram showing the flow of a frame determination process for a certain frame for which a simulation was executed. FIG. 7 is a diagram showing an example in which the fluctuation pattern exemplified in FIG. 5 is changed so that the charge and discharge conditions are more severe. FIG. 8 is a diagram showing an example in which the charge and discharge conditions are changed so that the charge and discharge conditions are more severe for another fluctuation pattern. FIG. 9 is a block diagram showing functional components of a battery control device 10 and an operation guidance device 11 provided in a battery control system 100C in a battery system 100 according to a third embodiment.

[0030] 1 is a diagram showing a schematic configuration of a storage battery system 100 according to a first embodiment of the present invention. The storage battery system 100 mainly includes a storage battery 100B and a storage battery control system 100C.

[0031] The storage battery 100B is configured as a module string in which a large number of module batteries 12 are connected in series. However, for the sake of simplicity, only one module battery 12 is shown in FIG.

[0032] Each module battery 12 generally has a structure in which a battery assembly 13 made up of a plurality of unit cells (not shown) is housed in a housing.

[0033] Each module battery 12 is further equipped with a fan 14 and a heater 15 as temperature maintenance means for maintaining the temperature within a certain allowable range (operating temperature range) during operation of the module battery 12. Furthermore, a temperature sensor 16 is also provided for measuring the temperature of the module battery 12. Note that a single module battery 12 may have multiple temperature sensors 16 arranged therein.

[0034] The unit cells are, for example, sodium-sulfur batteries (NaS batteries) that use sulfur as the positive electrode active material and metallic sodium as the negative electrode active material. When the unit cells are NaS batteries, an exothermic reaction occurs in each unit cell, in which metallic sodium reacts with sulfur to produce sodium polysulfide, causing the temperature of the battery module 12 to rise. However, the heat resistance of the components of a NaS battery, particularly the solid electrolyte tube, the aluminum container, the α-alumina insulating ring interposed between the two when they are joined, and the glass joints, TCB joints, and aluminum welds that seal between these components, is limited. Furthermore, these components are prone to corrosion and degradation when in contact with highly chemically active materials such as sodium, sulfur, and sodium polysulfide at high temperatures for long periods of time. Therefore, it is undesirable for the temperature of the unit cells to exceed a certain value due to continued discharge, i.e., the continued exothermic reaction.

[0035] On the other hand, the conductivity of sodium ions in β-alumina, which serves as a solid electrolyte, and the conductivity of sulfur and sulfur-impregnated graphite felt, which serve as positive electrode active materials, increase with increasing temperature. In other words, the higher the temperature due to heat generated by discharge, the lower the internal resistance of the battery module 12. Therefore, when the cells are NaS batteries, it is preferable to operate the battery module 12 at high temperatures from the standpoint of charge / discharge efficiency. Furthermore, considering the diffusibility of the active material in the positive electrode and the equilibrium of the exothermic reaction during discharge, operation at low temperatures is disadvantageous in terms of charge recovery.

[0036] Considering the utilization of heat generated by the exothermic reaction during discharge and the constraints imposed by the characteristics of the materials and components that make up the NaS battery, when the cells are NaS batteries, the module battery 12 is generally operated within a temperature range of 280° C. to 350° C. Therefore, in this embodiment, this temperature range is considered to be the operating temperature range of the module battery 12.

[0037] In addition, in order to prioritize reducing the internal resistance of the battery and improving charge / discharge recovery, the operating temperature range of the module battery 12, whose single cells are NaS batteries, may be set to 305°C to 360°C.

[0038] A module string, each of which has the above-described configuration of module batteries 12, is connected to the DC side of a known PCS (AC-DC converter: Power Conversion System) via a charge / discharge current detector (neither of which is shown). The charge / discharge current detector measures the charge / discharge current flowing through the storage battery 100B. The AC side of the PCS is connected to a load, an external system, or the like via a transformer.

[0039] The battery control system 100C includes, as its main components, a battery control device 10 that controls the operation of the battery 100B, and an operation guidance device 11 that handles processes related to the operation of the battery 100B, such as creating an operation plan for the battery 100B and simulating the plan. That is, in this embodiment, the operation guidance device 11 functions as an exercise plan creation support device that supports the creation of an operation plan for the battery 100B.

[0040] In this embodiment, generally, the battery control device 10 controls the charge / discharge operation and temperature (battery temperature) of each module battery 12. More specifically, the battery control device 10 controls the PCS to control the charge / discharge operation of a module string made up of multiple module batteries 12, and the battery control device 10 controls the fan 14 and heater 15 of each module battery 12 to control the battery temperature. Figure 2 is a block diagram showing the functional components of the battery control device 10 and the operation guidance device 11.

[0041] The battery control device 10 can be realized by a general-purpose or dedicated computer (control computer) equipped with a CPU, memory, storage, etc. By loading and executing a predetermined program stored in the storage into the CPU, the battery control device 10 mainly includes, as functional components, a charge / discharge schedule acquisition unit 1, a charge / discharge control unit 2, a heater control unit 3, a heat dissipation control unit 4, and an operation history accumulation unit 5.

[0042] The charge / discharge schedule acquisition unit 1 acquires a schedule for charging and discharging the storage battery 100B (charge / discharge schedule), and provides the charge / discharge schedule to the charge / discharge control unit 2, the heater control unit 3, and the heat dissipation control unit 4.

[0043] In this embodiment, the charge / discharge schedule refers to an operation plan (operation plan) related to the charging and discharging schedule for the storage battery 100B, which is created by the storage battery control system 100C or externally, and which is determined to be adoptable as a result of a simulation previously performed by the operation guidance device 11.

[0044] The charge / discharge schedule includes, for example, the start and end times of charging and discharging, the output during discharging, the charge amount during charging, and the operating temperature range.

[0045] The charge / discharge control unit 2 controls the charging and discharging operations of the storage battery 100B in accordance with the contents of the charge / discharge schedule. In general, the charge / discharge control unit 2 connects the storage battery 100B to the outside when the discharge start time described in the charge / discharge schedule arrives, starts discharging from each module battery 12 to the outside, and then, when the discharge end time arrives, disconnects the storage battery 100B from the outside and ends the discharging. The charge / discharge control unit 2 also connects the storage battery 100B to the outside when the charge start time described in the charge / discharge schedule arrives, starts charging the storage battery 100B from the outside, and then, when the charge end time arrives, disconnects the storage battery 100B from the outside and ends charging each module battery 12 from the outside.

[0046] The charge and discharge control unit 2 controls the charging and discharging operations of the storage battery 100B by managing the depth of discharge of the entire storage battery 100B. The depth of discharge is an index that indicates the degree of discharge of the cells that make up the battery pack 13 of each module battery 12 in the storage battery 100B. When the depth of discharge is 0%, the module battery 12 is at the end of charge, and when the depth of discharge is 100%, the module battery 12 is at the end of discharge.

[0047] However, when multiple module batteries 12 are connected in series to form a module string, the depth of discharge of the cells that make up the battery assembly 13 in each module battery 12 is generally uniform. Therefore, in this embodiment, the depth of discharge of the entire storage battery 100B is expressed by a single common value, and this value is referred to as the depth of discharge control value.

[0048] In principle, the charge / discharge control unit 2 sets the depth of discharge of the storage battery 100B at 0% when it reaches the end of charge, and calculates a depth of discharge control value by successively increasing or decreasing the charge / discharge amount converted from the charge / discharge current value detected by the charge / discharge current detector from the initial value each time a charge / discharge operation is performed, and stores the latest value.The charge / discharge control unit 2 then controls the charge / discharge operation of the storage battery 100B so that the depth of discharge control value remains between 0%, which corresponds to the end of charge, and 100%, which corresponds to the end of discharge.A known control method can be appropriately applied to control the charge and discharge operations in the charge / discharge control unit 2, including the management of the depth of discharge.

[0049] The charge / discharge control unit 2 also monitors the measurement values ​​of the temperature sensors 16 provided in each module battery 12. If the measurement value obtained from any of the temperature sensors 16 is within the operating temperature range but approaches the upper or lower limit of that range, or if the operating temperature range is not met, the charge / discharge control unit 2 stops or postpones charging / discharging in accordance with the contents of the charge / discharge schedule.

[0050] The heater control unit 3 controls the operation (ON / OFF switching) of the heater 15 based on the measured temperature of each module battery 12 measured by the temperature sensor 16 and the set insulation temperature.

[0051] The heat radiation control unit 4 controls the operation (switching ON / OFF) of the fan 14 during a heat radiation control period described in a heat radiation schedule that is set based on the charge / discharge schedule.

[0052] The operational performance accumulation unit 5 accumulates, as log data, the actual values ​​(actual charge / discharge values) of the charge / discharge time and operational output (charge / discharge output) when charging / discharging is actually performed on the storage battery 100B based on the charge / discharge schedule (i.e., when the storage battery 100B is operated), together with the measured temperature values ​​(actual temperature values) of the individual module batteries 12 measured by the temperature sensor 16 during such operation.

[0053] Like the battery control device 10, the operational guidance device 11 can be realized by a general-purpose or dedicated computer (control computer) equipped with a CPU, memory, storage, etc. By loading and executing a predetermined program stored in the storage into the CPU, the operational guidance device 11 mainly includes, as functional components, an operational plan creation unit 6, a simulation execution unit 7, and an adoption determination unit 8.

[0054] The operation plan creation unit 6 is responsible for creating an operation plan (charge / discharge plan) for the storage battery 100B. The operation plan sets a charge / discharge period and a charge / discharge output for a predetermined planning period. The operation plan is created by an operator of the operation guidance device 11 operating input means such as a mouse, keyboard, or touch panel (not shown) provided on the control computer.

[0055] In this embodiment, a day (0:00 to 24:00) is divided into 30-minute unit time segments, also called "frames," and an operational plan is created by setting the charge / discharge output for each of the 48 frames each day for two weeks.

[0056] In this embodiment, a selection is further made between a mode in which the operational output is set constant for each unit time segment, and a mode in which the unit time segment is further divided into a plurality of pattern setting units at predetermined time intervals, and the operational output is set for each pattern setting unit, thereby varying the operational output for that unit time segment, and an operational plan with content corresponding to the selection is created.

[0057] The former is selected for a unit time segment in which charging / discharging is scheduled for, for example, a wholesale electricity market, etc. The latter is selected for a unit time segment in which charging / discharging is scheduled for, for example, a supply / demand balancing market, etc.

[0058] Note that instead of creating the operation plan in the operation plan creation unit 6, an operation plan created outside the operation guidance device 11 may be acquired. In this embodiment, this case is also included in the term "creating an operation plan."

[0059] The simulation execution unit 7 executes a simulation of the charge / discharge operation of the storage battery 100B according to the operation plan. Specifically, the remaining capacity (SOC) and the battery temperature are calculated for each predetermined time interval in each unit time segment. In this embodiment, the time interval in the simulation is the same as the time interval Δt used when varying the operation output in each unit time segment to create the operation plan, but the two may be different.

[0060] The depth-of-discharge control value stored in the charge / discharge control unit 2 is referenced when setting the initial value of the remaining capacity used in the simulation. The temperature of the module battery 12 obtained by the battery control device 10 from the temperature sensor 16 is referenced when setting the initial value of the battery temperature. Furthermore, if an abnormality occurs in the state of the storage battery 100B, the simulation execution unit 7 obtains that information and uses it to correct the simulation parameters.

[0061] The adoption determination unit 8 determines whether or not the operation plan that was the subject of the simulation can be adopted based on the results of the simulation performed by the simulation execution unit 7. Broadly speaking, the adoption determination unit 8 determines whether or not operation can be performed based on whether or not the SOC and battery temperature obtained by the simulation for each unit time segment included in the operation plan are within a predetermined allowable range. Then, based on the result of this determination, it determines whether or not the operation plan that was the subject of the simulation can be adopted. Note that information on the upper and lower limits (hereinafter, "constraint values") of the allowable ranges of the SOC and battery temperature is set in advance and stored in the operation guidance device 11.

[0062] Only the operation plans determined to be "adoptable" by the adoption determination unit 8 are included in the charge / discharge schedule acquired by the charge / discharge schedule acquisition unit 1 of the battery control device 10. The operation plans determined to be "unadoptable" by the adoption determination unit 8 are subject to correction or re-creation by the operation plan creation unit 6.

[0063] <Creating an Operation Plan> Next, the creation of an operation plan performed by the operator of the operation guidance device 11 using the functions of the operation plan creation unit 6 will be described in more detail. When creating an operation plan in this embodiment, as described above, charging and discharging in a market where the operation output fluctuates, such as when bidding in a supply and demand adjustment market, is also considered, and the operation output for each unit time segment is selected to be either a constant value or fluctuating. For unit time segments where the latter is selected, the fluctuation pattern is also set.

[0064] 3 is a diagram showing in tabular form an operation plan created by the operation guidance device 11. Column R1 lists the date, column R2 lists the number of the frame (unit time segment), column R3 lists the "output segment" in which the operation output (charge / discharge output) of the frame is selected to be "constant" or "variable," and column R4 lists the operation output as "set output P (kW)."

[0065] The operator of the operation guidance device 11 selects the output category and sets the set output P for all frames in the period for which the operation plan is to be created.

[0066] However, for frames whose operational output is set to variable, they are also numbered in column R3 according to the type of variation pattern. In the example shown in Figure 3, for frames numbered "2" and "3," the output category is written as "Variation 1" in column R3. This indicates that a common variation pattern is set for these two frames. If there are frames for which other variation patterns are set, they will be sequentially written as "Variation 2," "Variation 3," etc. in column R3 for the frames to which those variation patterns are adopted.

[0067] In addition, among the frames for which the output classification is set to "constant" in column R3 and a positive number is written in column R4, frames for which a positive value is written as "set output P (kW)" in column R4 are planned to be discharged at the discharge power of that value, and frames for which a negative value is written are planned to be charged at the charge power of that absolute value.

[0068] On the other hand, for frames whose output category is set to "Variation 1" in column R3, the "Set output P (kW)" in column R4 lists the maximum output value (positive value) that serves as the reference output in the planned variation pattern for that frame.

[0069] Figure 4 is a diagram showing in table form the setting contents of the fluctuation pattern of the frame whose output category is set to "Fluctuation 1" in column R3 of Figure 3. In the example shown in Figure 4, the time interval Δt is set to 1 minute, and the unit time section of 30 minutes is further divided into pattern setting units for each relevant time interval Δt.

[0070] Column R5 lists the number "n" of each pattern setting unit, and column R6 lists the "elapsed time" from the start of the unit time segment to the end of the time interval Δt that provides each pattern setting unit. In the case shown in Figure 4, the time interval Δt is set to 1 minute, so the values ​​in columns R5 and R6 are the same, but the values ​​may differ depending on the setting of the time interval Δt.

[0071] Additionally, column R7 lists the value of "Rn," which is the output ratio applied to each pattern setting unit. This output ratio Rn is a coefficient by which the set output P is multiplied for each pattern setting unit, n = 1 to 30. That is, the operational output Pn(n) for the nth pattern setting unit is calculated using the set output P set in the operation plan and the output ratio Rn(n) set for the nth pattern setting unit using the following formula: Pn(n) = P × Rn(n) (1). Note that when the operational output Pn(n) is set to a discharge output, the output ratio Rn is set to a positive value, and when it is set to a charge output, the output ratio Rn is set to a negative value.

[0072] By changing the output ratio Rn(n) for each pattern setting unit n = 1 to 30, the operational output Pn(n) will be a different value depending on the value of n, and the operational output set within the unit time segment will fluctuate for each time increment Δt.

[0073] For frames for which the output category is set to "variable", the operator of the operational guidance device 11 also sets the output ratio Rn for all pattern setting units of the frame.

[0074] As described above, when creating an operational plan, the mode of setting the output ratio for each time increment Δt only for the unit time segment in which a fluctuation pattern is set has the advantage of reducing the amount of data compared to the mode of setting the output ratio for each time increment in the same way for the unit time segment in which the operational output is constant.

[0075] 5 is a diagram illustrating an example of a fluctuation pattern of operational output (charge / discharge output) in a certain unit time segment. In the fluctuation pattern shown in FIG. 5, three discharges D1 to D3 at Rn=1.0, i.e., set output P, ​​and one charge C1 at Rn=-1.0, i.e., set output P, ​​are performed.

[0076] However, as described above, a plan for varying operational output within one unit time segment is made with charging and discharging in a balancing market or the like in mind, and the specific mode of charging and discharging operation to be performed in the balancing market is usually not determined until the timing of its execution. Therefore, when setting a two-week operation plan as described above, even if a fluctuation pattern is set for some unit time segments with the intention of application to a balancing market or the like, the charging and discharging operation required when that unit time segment actually arrives may differ from the fluctuation pattern set for that unit time segment.

[0077] In some cases, even if it is determined at the time of creating the operation plan that storage battery 100B can be operated without problems even if it includes such a fluctuation pattern for a certain unit time segment, in reality, charging and discharging operations cannot be performed in accordance with such fluctuation pattern, and therefore, a malfunction may occur in which the SOC and battery temperature deviate from the allowable range, making it impossible to perform charging and discharging operations in subsequent unit time segments.

[0078] In this embodiment, the possibility of such a problem occurring is sufficiently reduced by devising a method for setting the output ratio Rn. In summary, several setting indexes are selected in advance, reference values ​​for the setting indexes are calculated from actual values ​​of charge / discharge outputs for past charging / discharging operations performed in a common application with the unit time segment for which a fluctuation pattern is to be set (for example, charging / discharging to a supply-demand balancing market), and the output ratio Rn is set so that the calculated value (index value) of the setting index calculated based on the fluctuation pattern to be set matches the reference value to a high degree.

[0079] Specifically, when creating an operation plan, the operation plan creation unit 6 extracts multiple pieces of log data of operation output (log data for calculating index values) for unit time segments in which charge / discharge operations were performed for a purpose common to the unit time segment for which a fluctuation pattern is set, from log data on past charge / discharge operations of the storage battery 100B accumulated in the operation performance accumulation unit 5 of the storage battery control device 10. For example, the log data for each past unit time segment may be linked to the purpose of the performed charge / discharge operations, and when an operator of the operation guidance device 11 inputs the purpose to which the fluctuation pattern is to be applied when creating an operation plan including a fluctuation pattern, the log data linked to the purpose may be extracted in response as log data for calculating index values.

[0080] Then, the values ​​of the following set indicators (a) to (g) are calculated based on the actual values ​​of the operational output Pn and the output ratio Rn determined from the actual output for each of the extracted log data for calculating an index value, and the average value (average index value) for each set indicator is calculated based on the calculated values ​​obtained, where the length of the unit time segment is T (= 30 minutes), n = 1 to T / Δt, and k is a natural number.

[0081] Setting indicator (a): Total discharge output ratio = Σ(Rn(n)), provided that Rn(n) > 0; Setting indicator (b): Total charge output ratio = Σ(-Rn(n)), provided that Rn(n) < 0; Setting indicator (c): Total operational output ratio = Total discharge output ratio + Total charge output ratio; Setting indicator (d): Actual discharge output ratio = Total discharge output ratio - Total charge output ratio; Setting indicator (e): Actual charge output ratio = Total charge output ratio - Total discharge output ratio; Setting indicator (f): Maximum cumulative output ratio = Maximum value of Σ(Rn(k)) (k = 1 to n) for all n; Setting indicator (g): Minimum cumulative output ratio = Minimum value of Σ(Rn(k)) (k = 1 to n) for all n.

[0082] The total discharge output ratio of the setting index (a) is a value corresponding to the ratio of the actual value of the discharge output in a unit time division to the discharge output when discharge is performed in all unit time divisions (when Rn = 1 in all pattern setting units).

[0083] The total charge output ratio of the setting index (b) is a value corresponding to the ratio of the actual value of the charge output in the unit time segment to the charge output when charging is performed in all unit time segments (when Rn = -1 in all pattern setting units).

[0084] The total operational output ratio of the setting index (c) is the value corresponding to the case where either charging or discharging is performed in all unit time divisions of the total actual value of charging and discharging in the unit time division (when Rn = 1 or Rn = -1 in all pattern setting units).

[0085] The actual discharge output ratio of the set indicator (d) and the actual charge output ratio of the set indicator (e) are values ​​corresponding to the actual discharge output or charge output (net charge / discharge amount) in the unit time segment, respectively.

[0086] The maximum cumulative output ratio of the setting index (f) and the minimum cumulative output ratio of the setting index (g) are values ​​corresponding to the maximum and minimum values ​​of the operational output from the start to the end of the unit time segment, respectively.

[0087] These set indices relate to at least one of an increase in battery temperature and an increase or decrease in SOC. Specifically, set indices (a), (b), and (c) relate to an increase in battery temperature, set indices (a), (d), and (f) relate to an increase in SOC, and set indices (b), (e), and (g) relate to a decrease in SOC.

[0088] When a fluctuation pattern is set for a unit time segment, the output ratio Rn(n) for each pattern setting unit is set so that the index value for at least one of the setting indexes (a) to (g) for that fluctuation pattern matches the average index value, which is the reference value for that index.

[0089] In one exemplary embodiment, of the plurality of index value calculation log data used to calculate the average index value, the output ratio Rn(n) of the index value calculation log data whose calculated values ​​for the set indexes (a) to (g) are close to the average index value is used as is to set the fluctuation pattern. Alternatively, the output ratio Rn(n) obtained in this embodiment may be adjusted so that the value for at least one of the set indexes (a) to (g) is closer to the average index value, and then used to set the fluctuation pattern.

[0090] As described above, in this embodiment, when a fluctuation pattern is set for a certain unit output category for the purpose of bidding in a supply and demand adjustment market, the output ratio Rn(n) is set so that the index values ​​for the setting indexes (a) to (g) that have a large effect on the battery state (SOC and battery temperature) are close to the average values ​​of past performance, and a fluctuation pattern is created.

[0091] This reduces the possibility that the storage battery 100B will become inoperable even if the charge / discharge operation actually required in the supply and demand balancing market differs from the created operation plan, which leads to favorable bidding in the supply and demand balancing market.

[0092] Furthermore, since the plan is based on past performance, the possibility that the created operational plan will be deemed unacceptable in the simulation is reduced, thereby improving the accuracy and efficiency of creating operational plans that include fluctuation patterns.

[0093] <Simulation and Adoption Determination> Next, we will explain the simulation of charging and discharging operations in the storage battery 100B according to the operation plan performed by the simulation execution unit 7, and the determination of whether the operation plan can be adopted by the adoption determination unit 8 based on the results of the simulation.

[0094] Fig. 6 is a diagram showing the flow of a simulation. The simulation is performed for all "frames" (i.e., unit time segments) of the created operation plan, but Fig. 6 shows an example of a simulation for one particular frame.

[0095] First, initial values ​​of the simulation parameters are set (step S1). The initial values ​​are set for the following: operating output time: T; time interval: Δt; operating output: Pn; remaining capacity: SOC; battery temperature: Temp; and output class: F (0 → constant, 1 → variable).

[0096] More specifically, the operation output time T is 30 minutes, which is the length of the frame. The time interval Δt is set to approximately 10 seconds to 10 minutes, which is the same as the time interval when setting the fluctuation pattern. The operation output Pn is set to the set output value of the frame described in the operation plan.

[0097] The initial value of the remaining capacity SOC is set based on the depth-of-discharge control value at the start of the operation plan to be simulated. In this embodiment, the remaining capacity SOC = 100% - depth of discharge (control value).

[0098] The initial value of the battery temperature Temp is set in the range of 305° C. to 360° C. depending on the battery temperature of the frame immediately preceding the frame being simulated.

[0099] Furthermore, although the SOC and battery temperature of each of the module batteries 12 that make up the storage battery 100B may differ in nature, these module batteries 12 are connected in series to form a module string, and therefore in the simulation, the individual module batteries 12 are not distinguished from one another, and the remaining capacity SOC and battery temperature Temp of each module battery 12 are assumed to be the same, and each is represented by a single simulation value.

[0100] As the output category F, a flag (output category flag F) is set according to whether the output category set for the frame that is the subject of the simulation is "constant" or "variable" as shown in column R3 in Fig. 3. In this embodiment, the output category flag F is set to "0" for frames whose output category is set to "constant" in the operation plan, and the output category flag F is set to "1" for frames whose output category is set to "variable."

[0101] Next, the number of loops N to be executed in the latter half of the simulation is calculated by the formula N=T / Δt (step S2).

[0102] Next, n is set to 1 (step S3), and the battery current In is calculated from the operational output Pn (step S4).

[0103] Furthermore, the remaining capacity SOC at the point when time has passed by Δt is calculated using the value of the battery current In calculated in step S4, the time interval Δt set as the initial value in step S1, and the most recent value of the remaining capacity SOC according to the formula SOC = SOC - In × Δt (step S5).

[0104] Furthermore, the battery temperature Temp at the point in time Δt has elapsed is calculated using the formula Temp = Temp + (In × In × r) × Δt / C from the value of the battery current In calculated in step S4, the time interval Δt set as an initial value in step S1, the most recent battery temperature Temp, and the internal resistance r, heat dissipation loss, and heat capacity C of the module battery 12 (step S6). Here, the internal resistance r, heat dissipation loss, and heat capacity C of the module battery 12 are constants that are specified in advance and stored in a memory unit (not shown) of the operational guidance device 11. The order of steps S5 and S6 may be reversed, or both may be performed in parallel.

[0105] As described above, in this embodiment, the internal resistance r is taken into consideration when calculating the battery temperature. The internal resistance r varies depending on the remaining capacity and battery temperature, and is also related to the charge / discharge efficiency, which affects the remaining capacity. However, in Patent Document 2, the internal resistance of the battery is not taken into consideration. Furthermore, the remaining capacity prediction accuracy in the simulation performed in this embodiment is higher than the remaining capacity prediction accuracy disclosed in Patent Document 2.

[0106] Next, n=n+1 is set (step S7), and if n>N is not satisfied for the new n (NO in step S8), steps S5 to S7 are repeated at every time step Δt.

[0107] On the other hand, if n>N (YES in step S8), the simulation for the target frame ends, and the process proceeds to frame determination processing (step S9) for determining whether the settings of the frame can be used in the storage battery 100B. Note that the process may proceed to frame determination processing after the simulation for all frames ends.

[0108] FIG. 7 is a diagram showing the flow of the frame determination process for a certain frame for which a simulation has been executed according to the procedure shown in FIG.

[0109] In the frame determination process, it is first determined whether the output classification flag F set for the frame to be determined is "0" or "1" (step S10).

[0110] When F = 0, i.e., when the operational output set for the frame to be judged is constant, the adoption / non-adoption judgment unit 8 judges whether the remaining capacity (SOC) calculated in step S5 and the battery temperature calculated in step S6 for the last time increment Δt where n = N in the simulation are values ​​within the allowable range (step S11a).

[0111] If both the remaining capacity and the battery temperature are within the allowable range (YES in step S11a), the employability determination unit 8 determines that the planned operation for the frame is "allowable" (step S12a). If at least one of the remaining capacity and the battery temperature is out of the allowable range (NO in step S11a), the employability determination unit 8 determines that the planned operation for the frame is "unallowable" (step S12b).

[0112] On the other hand, when F=1, i.e., when a fluctuation pattern is set for the frame to be judged, the adoption / non-adoption judgment unit 8 judges whether the remaining capacity (SOC) calculated in step S5 and the battery temperature calculated in step S6 for all time increments Δt of n=1 to N in the simulation are all values ​​within the allowable range (step S11b).

[0113] If the calculation results of the remaining capacity and battery temperature at all time intervals Δt for n=1 to N are all within the allowable range (YES in step S11b), the employability determination unit 8 determines that the planned operation for that frame is "allowable" (step S12a).If any of the calculation results of the remaining capacity and battery temperature at all time intervals Δt for n=1 to N deviates from the allowable range (NO in step S11a), the employability determination unit 8 determines that the planned operation for that frame is "unallowable" (step S12b).

[0114] The adoption possibility determination unit 8 performs the frame determination process described above for all frames included in the operation plan. Then, only when the operation of all frames is determined to be "adoptable," the operation plan is determined to be "adoptable." If there is even one frame whose operation is determined to be "unadoptable," the operation plan is determined to be "unadoptable."

[0115] The adoption determination unit 8 displays the determination result on a display unit (not shown). In addition, the operation plan determined to be "unadoptable" is appropriately corrected by the operator. In this case, the simulation results of the pieces determined to be "unadoptable" for operation may be appropriately displayed on the display unit to serve as a reference for such correction.

[0116] As explained above, according to this embodiment, when creating an operation plan for a storage battery, it is necessary to vary the operation output of some of the unit time segments in the operation plan for purposes such as bidding in a supply and demand adjustment market, and even in cases where the fluctuation in the actual operation output cannot be determined in advance, it is possible to reduce the possibility that the storage battery will become unable to operate because the actual charging and discharging operation differs from the plan.

[0117] In the first embodiment described above, when creating an operation plan for storage battery 100B that includes a fluctuation pattern in at least some unit time segments, an average index value for set indexes (a) to (g) is calculated as a reference value based on the log data for calculating index values, and the value of output ratio Rn(n) that provides the fluctuation pattern is set so that at least one of the index values ​​for set indexes (a) to (g) approaches the average index value. This is done to avoid a situation in which storage battery 100B becomes unable to operate even if the charge / discharge operation required for storage battery 100B to which the operation plan is applied differs from the plan. In this embodiment, a fluctuation pattern is set with the intention of more reliably avoiding such a situation.

[0118] This is achieved by setting a fluctuation pattern so that, for at least one of the index values ​​for the set indicators (a) to (g), at least one of the remaining capacity and temperature of the storage battery 100B is closer to the upper or lower limit of the allowable range compared to when the indicator values ​​are set to match the average index value, i.e., by setting a fluctuation pattern so that the charging and discharging conditions are more severe.

[0119] Specifically, when focusing on the set indicators (a) to (c) and the set indicator (f), at least one of the indicator values ​​for those in the set fluctuation pattern should be greater than the average indicator value. This can be done, for example, by making at least one of those indicator values ​​equal to the maximum value in the log data for calculating the indicator values, or by making it equal to the average indicator value + kσ (σ is the standard deviation when the average indicator value is obtained, and k is a natural number).

[0120] Furthermore, when focusing on the set indicators (d) to (e), it is sufficient that at least one of the absolute values ​​of the indicator values ​​for those in the set fluctuation pattern is greater than the average index value. This can be done in the same manner as in the case of the set indicators (a) to (c) and the set indicator (f) described above, except that absolute values ​​are used.

[0121] Furthermore, when focusing on the set index (g), it is sufficient to make the index value in the set fluctuation pattern smaller than the average index value. For example, this can be done by making the index value equal to the minimum value in the log data for calculating the index value, or by making the index value equal to the average index value -kσ.

[0122] 8A and 8B are diagrams showing an example in which the variation patterns shown in Fig. 5 are changed to make the charge / discharge conditions more severe. Fig. 8A shows the same base pattern as the variation patterns shown in Fig. 5.

[0123] Figure 8(b) shows an example of a variation pattern in which the discharge times of the three discharges D1 to D3 set in the base pattern are increased to discharges D1α to D3α in order to increase the index values ​​for the set indicators (a), (c), and (f) and the absolute values ​​of the index values ​​for the set indicators (d) and (e) compared to the base pattern.

[0124] Figure 8(c) shows an example of a variation pattern in which the discharge times for the three discharges D1 to D3 set in the base pattern are increased to discharges D1α to D3α, and the charge time for one charge C1 is increased to charge C1β, in order to increase the index values ​​for the set indicators (a) to (c) and (f) compared to the base pattern.

[0125] Figure 8(d) illustrates a variation pattern in which the discharge times of the three discharges D1 to D3 set in the base pattern are increased to discharges D1γ to D3γ, and the charging time for one charge C1 is reduced to charge C1γ, in order to increase the index values ​​for the set indicators (a), (c), and (f) compared to the base pattern and increase the absolute values ​​of the index values ​​for the set indicators (d) and (e) compared to the base pattern.

[0126] 8(b) to 8(d) by setting the index value of interest to a value equivalent to the average index value + kσ, the constant k is determined to satisfy the relationship of time step Δt<kσ, and the time step Δt, the number of integer values ​​obtained by rounding up the decimal point of the value kσ / Δt, is allocated as evenly as possible to each discharge in the base pattern (variation pattern that gives the average index value). The same applies to the case where the charging time is reduced by setting the index value of interest to a value equivalent to the average index value - kσ.

[0127] FIG. 9 is a diagram showing an example in which the charge / discharge conditions are changed to be more severe for another variation pattern.

[0128] In Fig. 9(a), a variation pattern is set in which an initial discharge D11 is followed by two alternating charges C11 and C12 and two alternating discharges D12 and D13, followed by a final charge C13, whereas in Fig. 9(b), the initial discharge D11 and the final charge C13 are changed to a long discharge D20 and charge C20, respectively, with a pause interval I20 between them. This change maximizes the index value for the set index (f) and minimizes the index value for the set index (g).

[0129] As described above, if the fluctuation pattern is set so that the charging and discharging conditions are more severe, it is considered that there is a low possibility that the output will deviate from the allowable range during actual charging and discharging operations.

[0130] As a confirmation, the setting of a fluctuation pattern in which the charge / discharge conditions are made more severe in this embodiment is performed only within the range in which operation is judged to be "possible" in the frame judgment process in the adoption / non-adoption judgment unit 8. If, for example, an operation plan including a fluctuation pattern with more severe charge / discharge conditions for a certain frame is subjected to simulation and further frame judgment process, and the operation is judged to be "not possible," then naturally, the fluctuation pattern will need to be modified.

[0131] As described above, according to this embodiment, when creating an operation plan, if the operational output set for a certain unit time segment is set as a fluctuation pattern, the fluctuation pattern is set so that the charge / discharge conditions are more severe. This reduces the possibility that the output will deviate from the allowable range during actual charge / discharge operations, resulting in failure to achieve charge / discharge operations according to the operation plan.

[0132] <Variation of the second embodiment> When setting a fluctuation pattern so that the charging and discharging conditions are more severe, a simulation may be performed on an operation plan in which a fluctuation pattern is set so that at least one of the index values ​​for the set indexes (a) to (g) matches the average index value, and based on the results, the fluctuation pattern may be re-set so that the charging and discharging conditions are more severe.

[0133] Specifically, the variation pattern is set so that the charge / discharge conditions become more severe, focusing on the index values ​​that have a large effect on the simulated battery temperature and SOC with small tolerances at the upper and lower limits.

[0134] 10 is a block diagram showing functional components of a battery control device 10 and an operational guidance device 11 provided in a battery control system 100C in a battery system 100 according to a third embodiment of the present invention. Most of the functional components of the battery control device 10 and the operational guidance device 11 are the same as those in the first embodiment shown in FIG. 2 . However, this embodiment differs from the first and second embodiments in that the adoption determination unit 8 provided in the operational guidance device 11 includes a realization probability calculation unit 9.

[0135] The realization probability calculation unit 9 calculates the probability (plan realization probability) that the fluctuation pattern included in the operation plan can be implemented based on the battery temperature and remaining capacity for each time interval Δt (i.e., for each pattern setting unit) calculated by simulation in the simulation execution unit 7, and their respective allowable ranges (constraint values).

[0136] Specifically, the realization probability calculation unit 9 calculates the plan realization probability based on the following formula.

[0137] Plan realization probability = STemp × SSocUL × SSocLL (2) where STemp is a temperature coefficient, SSocUL is a capacity upper limit coefficient, and SSocLL is a capacity lower limit coefficient. Each of these coefficients is set to take a value within the range of 0 to 1 depending on the magnitude relationship with the constraint value.

[0138] The temperature coefficient STemp is set so that the closer the maximum battery temperature value for each time interval Δt is to the upper limit of the battery temperature as a constraint value, the closer it is to 0, and the farther it is from the upper limit, the closer it is to 1.

[0139] The capacity upper limit coefficient SSocUL is set so that the closer the maximum value of the remaining capacity for each time interval Δt is to the upper limit, which is a constraint value, the closer it is to 0, and the farther it is from the upper limit, the closer it is to 1.

[0140] The capacity lower limit coefficient SSocLL is set so that the closer the minimum value of the remaining capacity for each time interval Δt is to the lower limit, which is a constraint value, the closer it is to 0, and the farther it is from the lower limit, the closer it is to 1.

[0141] In such a case, the larger the value of the plan realization probability calculated from equation (2), the higher the probability that the operation plan including the simulated fluctuation pattern can actually be implemented, and the smaller the value of the plan realization probability, the lower the probability that the operation plan including the simulated fluctuation pattern can actually be implemented.

[0142] For example, the temperature coefficient STemp, the capacity upper limit coefficient SSocUL, and the capacity lower limit coefficient SSocLL can be set as follows based on the difference values ​​between the maximum battery temperature value TempCalc, the maximum remaining capacity value SocCalcMax, and the minimum remaining capacity value SocCalcMin for each time interval Δt obtained by simulation in the simulation execution unit 7 and the respective constraint values ​​TempUL (e.g., 360°C), SocUL (e.g., 100%), and SocLL (e.g., 0%):

[0143] [Temperature coefficient STemp] TempUL+5℃≦TempCalc:STemp=0; TempUL<TempCalc:STemp=0.05; TempUL-5℃<TempCalc≦TempUL:STemp=0.99; TempUL-10℃<TempCalc≦TempUL-5℃:STemp=0.999; TempCalc≦TempUL-10℃ :STemp=1.

[0144] [Capacity upper limit coefficient SSocUL] SocUL+5%≦SocCalcMax :SSocUL=0; SocUL<SocCalcMax≦SocUL+5% :SSocUL=0.05; SocUL−5%<SocCalcMax≦SocUL :SSocUL=0.99; SocUL−10%<SocCalcMax≦SocUL−5% :SSocUL=0.999; SocCalcMax≦SocUL−10% :SSocUL=1.

[0145] [Capacity lower limit coefficient SSocLL] SocCalcMin≦SocLL−10%: SSocLL=0; SocLL−10%<SocCalcMin≦SocLL: SSocLL=0.05; SocLL<SocCalcMin≦SocLL+5%: SSocLL=0.99; SocLL+5%<SocCalcMin≦SocLL+10%: SSocLL=0.999; SocLL+10%<SocCalcMin: SSocLL=1.

[0146] Alternatively, the temperature coefficient STemp, the capacity upper limit coefficient SSocUL, and the capacity lower limit coefficient SSocLL may be set based on the ratios TempCalc / TempUL, SocCalcMax / SocUL, and SocCalcMin / SocLL of the maximum battery temperature, maximum remaining capacity, and minimum remaining capacity, SocCalcMin, to the respective constraint values ​​TempUL, SocUL, and SocLL, respectively.

[0147] The adoption determination unit 8 displays the calculation result of the plan realization probability together with the result of the adoption determination for the operation plan on a display unit (not shown) of the operation guidance device 11. This allows the operator of the operation guidance device 11 to determine whether or not to actually perform charging / discharging operations based on the operation plan in the storage battery 100B, based on the value of the plan realization probability, even if the operation plan including the fluctuation pattern is determined to be "adoptable."

[0148] By indicating the probability of the plan being realized in this way, it is possible to determine whether or not to change the operation plan by comparing it with the adverse effects that would occur if the operation plan could not be implemented.

[0149] In such cases, it is possible to determine whether or not to adopt the operating plan after understanding the risk of not being able to implement the operating plan, thereby increasing the possibility of earning more profits compared to conventional technology, which simply determines whether or not to implement the charging and discharging plan.

[0150] Preferably, for the set indicators (c), (d), and (e) shown in the first embodiment, a fluctuation pattern is set so that the operational output is closer to the upper or lower limit of the allowable range compared to when those indicator values ​​are set to match the average indicator value, as in the second embodiment, and a simulation is performed on an operational plan including such a fluctuation pattern to calculate the probability of plan realization.

[0151] As described above, the setting indicator (c) is related to an increase in battery temperature, the setting indicator (d) is related to an increase in SOC, and the setting indicator (e) is related to a decrease in SOC. Therefore, by calculating the plan realization probability in this manner, the accuracy of the plan realization probability can be further improved.

[0152] As described above, according to this embodiment, when creating an operation plan that is designed to vary the operation output in some unit time segments, the probability that the operation plan (more specifically, its variation pattern) can be implemented is also calculated, making it possible to determine whether or not to adopt the operation plan after understanding the risk that the operation plan cannot be implemented. This not only reduces the possibility that the storage battery will become inoperable due to the actual charge / discharge operation differing from the operation plan, but also increases the possibility of earning more profits compared to conventional techniques that simply determine whether or not to implement the charge / discharge plan.

Claims

1. A method for creating an operation plan for a storage battery that describes the set values ​​of charge and discharge outputs for a predetermined period of time for each unit time segment, comprising: an output segment setting step of selectively setting each of a plurality of unit time segments to either a first unit time segment in which the charge and discharge output is constant or a second unit time segment in which the charge and discharge output is varied; and a variation pattern setting step of setting an output ratio, which is the ratio of the charge and discharge output to a reference output, for each of a plurality of pattern setting units obtained by dividing the unit time segment at predetermined time intervals, thereby setting a variation pattern of the charge and discharge output in the second unit time segment, wherein in the variation pattern setting step, a reference value for a predetermined setting indicator that has been selected in advance is calculated from actual charge and discharge output values ​​for past charge and discharge operations that have a common use with the second unit time segment for which the variation pattern is set, and the output ratio for the variation pattern is set so that an index value, which is the value of the setting indicator for the variation pattern, satisfies a predetermined condition based on the reference value.

2. A method for creating an operation plan for a storage battery according to claim 1, wherein, when the length of the unit time section is T, the predetermined time increment is Δt, the output ratio in the pattern setting unit for n, n = 1 to T / Δt, is Rn(n), and k is a natural number, the predetermined setting indexes are: Setting index (a): total discharge output ratio = Σ(Rn(n)), provided that Rn(n) > 0, Setting index (b): total charge output ratio = Σ(-Rn(n)), provided that Rn(n) < 0, Setting index (c): total operational output ratio = total discharge output ratio + total charge output ratio, Setting index (d): actual discharge output ratio = total discharge output ratio - total charge output ratio, Setting index (e): actual charge output ratio = total charge output ratio - total discharge output ratio, Setting index (f): maximum cumulative output ratio = maximum value of Σ(Rn(k)) (k = 1 to n) for all n, A method for creating an operation plan for a storage battery, wherein the setting index (g) is at least one of the following: minimum cumulative output ratio = minimum value of Σ(Rn(k)) (k = 1 to n) for all n.

3. A method for creating an operation plan for a storage battery as described in claim 2, characterized in that the reference value is set to the average value of calculated values ​​calculated from the actual charge / discharge output values ​​for multiple past charge / discharge operations for each of the setting indicators (a) to (g).

4. A method for creating an operation plan for a storage battery as set forth in claim 2 or claim 3, characterized in that in the fluctuation pattern setting step, the output ratio is set so that the index value for at least one of the setting indexes (a) to (g) matches the reference value.

5. A method for creating an operation plan for a storage battery as described in claim 3, characterized in that in the fluctuation pattern setting step, the fluctuation pattern is set so that at least one of the remaining capacity and temperature of the storage battery approaches the upper or lower limit of the allowable range compared to when the index value for at least one of the set indexes (a) to (g) is set to match the average value.

6. A method for creating an operation plan for a storage battery as described in claim 1, further comprising: a simulation step for performing a simulation of the remaining capacity and temperature of the storage battery when the storage battery is caused to perform charging and discharging operations based on the created operation plan for each of the plurality of unit time segments; and a judgment step for determining whether the operation plan can be adopted based on the results of the simulation, wherein in the judgment step, if the remaining capacity and the temperature obtained by the simulation for all of the plurality of unit time segments are within an allowable range, it is determined that the operation plan can be adopted.

7. A method for creating an operation plan for a storage battery as described in claim 6, characterized in that in the determination step, for the first unit time segment, it is determined that operation in accordance with the operation plan for that unit time segment is possible if the remaining capacity and the temperature at the end of the unit time segment are within an acceptable range, for the second unit time segment, it is determined that operation in accordance with the operation plan for that unit time segment is possible if the remaining capacity and the temperature for each pattern setting unit are all within an acceptable range, and when it is determined that operation is possible for all of the plurality of unit time segments, it is determined that the operation plan is adoptable.

8. A method for creating an operation plan for a storage battery according to claim 6, further comprising a realization probability calculation step of determining the realization probability of the operation plan, wherein the realization probability is the product of: a temperature coefficient STemp which is set to a value closer to 0 the closer the maximum temperature value of the storage battery at each time interval is to an upper temperature limit, and is set to a value closer to 1 the farther it is from the upper temperature limit; a capacity upper limit coefficient SSocUL which is set to a value closer to 0 the closer the maximum remaining capacity value at each time interval is to an upper capacity limit, and is set to a value closer to 1 the farther it is from the upper capacity limit; and a capacity lower limit coefficient SSocLL which is set to a value closer to 0 the closer the minimum remaining capacity value at each time interval is to a lower capacity limit, and is set to a value closer to 1 the farther it is from the lower capacity limit.

9. A device for supporting the creation of an operation plan for a storage battery in which set values ​​of charge / discharge output for a predetermined period are described for each unit time segment, the device comprising: an output segment setting means for selectively setting each of a plurality of unit time segments to either a first unit time segment in which the charge / discharge output is constant or a second unit time segment in which the charge / discharge output is varied; and a fluctuation pattern setting means for setting a fluctuation pattern of the charge / discharge output in the second unit time segment by setting an output ratio, which is the ratio of the charge / discharge output to a reference output, for each of a plurality of pattern setting units obtained by dividing the unit time segment at predetermined time intervals, wherein the fluctuation pattern setting means calculates a reference value for a predetermined setting index selected in advance from actual charge / discharge output values ​​for past charge / discharge operations that have a common use with the second unit time segment for which the fluctuation pattern is set, and is also capable of calculating an index value, which is the value of the set index for the fluctuation pattern; and when creating the fluctuation pattern, it is possible to set the output ratio such that the index value satisfies a predetermined condition based on the reference value. A storage battery operation plan creation support device characterized by:

10. A storage battery operation plan creation support device according to claim 9, wherein, when the length of the unit time section is T, the predetermined time increment is Δt, the output ratio in the pattern setting unit for n, n = 1 to T / Δt, is Rn(n), and k is a natural number, the predetermined setting indexes are: Setting index (a): total discharge output ratio = Σ(Rn(n)), where Rn(n) > 0, Setting index (b): total charge output ratio = Σ(-Rn(n)), where Rn(n) < 0, Setting index (c): total operational output ratio = total discharge output ratio + total charge output ratio, Setting index (d): actual discharge output ratio = total discharge output ratio - total charge output ratio, Setting index (e): actual charge output ratio = total charge output ratio - total discharge output ratio, Setting index (f): maximum cumulative output ratio = maximum value of Σ(Rn(k)) (k = 1 to n) for all n, A storage battery operation plan creation support device, characterized in that the setting index (g) is at least one of the following: minimum cumulative output ratio = minimum value of Σ(Rn(k)) (k = 1 to n) for all n.

11. A storage battery operation plan creation support device as described in claim 10, characterized in that the reference value is an average value of calculated values ​​calculated from the charge / discharge output actual values ​​for a plurality of the past charge / discharge operations for each of the setting indicators (a) to (g).

12. A storage battery operation plan creation support device as set forth in any one of claims 9 to 11, further comprising: simulation means for performing a simulation of the remaining capacity and temperature of the storage battery when the storage battery is caused to perform charging and discharging operations based on the created operation plan for each of the plurality of unit time segments; and judgment means for determining whether or not the operation plan can be adopted based on the results of the simulation, wherein the judgment means determines that the operation plan can be adopted when the remaining capacity and the temperature obtained by the simulation for all of the plurality of unit time segments are within an allowable range.

13. A storage battery operation plan creation device as described in claim 12, wherein the determination means determines that operation in accordance with the operation plan for the first unit time segment is possible if the remaining capacity and the temperature at the end of the unit time segment are within an acceptable range, determines that operation in accordance with the operation plan for the second unit time segment is possible if the remaining capacity and the temperature for each pattern setting unit are all within an acceptable range, and determines that the operation plan is adoptable if it is determined that operation is possible for all of the plurality of unit time segments.

14. A storage battery operation plan creation support device according to claim 12, further comprising: realization probability calculation means for calculating the realization probability of the operation plan, wherein the realization probability is the product of: a temperature coefficient STemp which is set to a value closer to 0 the closer the maximum temperature value of the storage battery at each time interval is to an upper temperature limit, and is set to a value closer to 1 the farther it is from the upper temperature limit; a capacity upper limit coefficient SSocUL which is set to a value closer to 0 the closer the maximum remaining capacity value at each time interval is to an upper capacity limit, and is set to a value closer to 1 the farther it is from the upper capacity limit; and a capacity lower limit coefficient SSocLL which is set to a value closer to 0 the closer the minimum remaining capacity value at each time interval is to a lower capacity limit, and is set to a value closer to 1 the farther it is from the lower capacity limit.

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