Energy storage system operation support device and method

Abstract

An operation support device according to one embodiment of the present invention is an operation support device for an energy storage system, and may include at least one processor and a memory for storing at least one instruction to be executed through the at least one processor. The at least one instruction may include an instruction to collect information on batteries and inverters that can be applied to the energy storage system; an instruction to derive a plurality of combinations, each consisting of one or more batteries and inverters, based on the structure of the energy storage system; an instruction to calculate the operating cost of the energy storage system for each of the combinations; and an instruction to generate recommended combination information including information on the combination that shows the lowest operating cost among the combinations.

Description

[Technical Field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2023-0092219, filed with the Korean Intellectual Property Office on July 17, 2023, and all of the contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to an operation support device and method for an energy storage system, and more particularly to an operation support device and method for an energy storage system that supports minimizing the operation cost of the energy storage system. [Background technology]

[0003] An energy storage system (ESS) is a system in which batteries that store energy are operated in conjunction with renewable energy and a power grid. In recent years, smart grids and renewable energy have become more widespread, and as the efficiency and stability of the power grid have become more important, the demand for energy storage systems has been increasing for power supply and demand adjustment and power quality improvement. Depending on the purpose of use, the output and capacity of energy storage systems can vary, and multiple battery systems can be connected to form a large-capacity energy storage system.

[0004] Among ESSs, ESSs linked to PV (Photovoltaic) systems are becoming increasingly popular. PV-linked ESSs are configured to appropriately distribute the power supplied from the power grid and the power generated by the PV system to supply the load, and store the remaining power in a battery system.

[0005] The most important goal for ESS users is to minimize the operating costs of the ESS. The costs incurred by users during the operation of an ESS consist of the grid power purchase cost that must be paid periodically and the battery replacement cost that occurs each time the battery is replaced. In general, ESSs are controlled by taking into account various factors such as the amount of power generated by the PV system, the power demand of the load, and the state of charge of the battery. However, conventional technologies focus on ESS control methods to improve power efficiency or battery performance, and are limited in their ability to minimize the costs incurred by users from the perspective of long-term operation of the ESS.

[0006] Therefore, there is a need for an appropriate energy storage system operation support technology that helps minimize the long-term operation costs of the energy storage system. Summary of the Invention [Problem to be solved by the invention]

[0007] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an operation support device for an energy storage system that supports minimizing the operation cost of the energy storage system.

[0008] Another object of the present invention to solve the above problems is to provide an operation support method using such an operation support device. [Means for solving the problem]

[0009] To achieve the above object, an operation support device according to one embodiment of the present invention is an operation support device for an energy storage system, and may include at least one processor and a memory for storing at least one instruction to be executed through the at least one processor.

[0010] The at least one instruction may include an instruction to collect information on batteries and inverters that can be applied to the energy storage system; an instruction to derive a plurality of combinations, each consisting of one or more batteries and inverters, based on the structure of the energy storage system; an instruction to calculate the operating cost of the energy storage system for each of the combinations; and an instruction to generate recommended combination information including information on the combination that shows the lowest operating cost among the combinations.

[0011] The instructions to collect information about the batteries and inverters may include instructions to collect one or more of the model name, capacity, threshold SOC range, and purchase cost for each of the batteries, and the model name, power limit, and purchase cost for each of the inverters.

[0012] The instruction to derive the plurality of combinations may include an instruction to derive a range of battery numbers based on the battery capacity and the inverter output limit; and an instruction to derive a plurality of combinations applicable to the energy storage system based on the range of battery numbers and the design structure of the battery system.

[0013] The instructions for calculating the operating costs of the energy storage system may include instructions for calculating a grid power purchase cost and a battery and inverter purchase cost for each of the combinations; and instructions for calculating the operating costs based on the grid power purchase cost and the battery and inverter purchase cost.

[0014] The instructions for calculating the operating cost of the energy storage system may include instructions for calculating a grid power purchase cost for a predetermined period for each of the combinations based on historical information regarding one or more of the energy storage system, a load associated with the energy storage system, and a power generation device associated with the energy storage system.

[0015] The instruction to calculate the grid power purchase cost may include an instruction to collect information on the power consumption state of the load and information on the power generation state of the power generation device; an instruction to derive an operation schedule including charge / discharge amounts for each time interval that minimizes the grid power purchase cost using an objective function defined as the grid power purchase cost; and an instruction to apply the operation schedule and grid power cost information to the energy storage system according to each of the combinations to calculate the grid power purchase cost for a predetermined period for each of the combinations.

[0016] Here, the objective function can define constraints including at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the battery's charge / discharge efficiency, a third condition regarding the battery's limit charge amount, a fourth condition regarding the inverter's limit output, and a fifth condition regarding the binarization of the charge state and discharge state.

[0017] The at least one instruction may further include an instruction to provide the generated recommended combination information to a user terminal that interfaces with the energy storage system.

[0018] Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, a battery connection structure, and an inverter model name.

[0019] To achieve the above-mentioned still another object, an operation support method according to one embodiment of the present invention is a method for supporting operation of an energy storage system, and includes the steps of: collecting information on batteries and inverters that can be applied to the energy storage system; deriving a plurality of combinations, each consisting of one or more batteries and inverters, based on the structure of the energy storage system; calculating the operating cost of the energy storage system for each of the combinations; and generating recommended combination information including information on the combination that shows the lowest operating cost among the combinations.

[0020] The step of collecting information about the batteries and inverters may include collecting one or more of the model name, capacity, threshold SOC range, and purchase cost for each of the batteries, and the model name, limit power output, and purchase cost for each of the inverters.

[0021] The step of deriving the plurality of combinations may include the steps of: deriving a range of battery numbers based on the battery capacity and the inverter output limit; and deriving a plurality of combinations applicable to the energy storage system based on the range of battery numbers and the design structure of the battery system.

[0022] Calculating the operating cost of the energy storage system may include calculating a grid power purchase cost and a battery and inverter purchase cost for each of the combinations; and calculating the operating cost based on the grid power purchase cost and the battery and inverter purchase cost.

[0023] The step of calculating the operating cost of the energy storage system may include a step of calculating a grid power purchase cost for a predetermined period for each of the combinations based on historical information regarding one or more of the energy storage system, a load coupled to the energy storage system, and a power generation device coupled to the energy storage system.

[0024] The step of calculating the grid power purchase cost may include the steps of: collecting information on the power consumption state of the load and information on the power generation state of the power generation device; deriving an operation schedule including charge / discharge amounts for each time interval, which minimizes the grid power purchase cost, using an objective function defined as the grid power purchase cost; and applying the operation schedule and grid power cost information to the energy storage system according to each of the combinations to calculate the grid power purchase cost for a predetermined period for each of the combinations.

[0025] Here, the objective function can define constraints including at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the battery's charge / discharge efficiency, a third condition regarding the battery's limit charge amount, a fourth condition regarding the inverter's limit output, and a fifth condition regarding the binarization of the charge state and discharge state.

[0026] The operation support method may further include an instruction to provide the generated recommended combination information to a user terminal interoperating with the energy storage system.

[0027] Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, a battery connection structure, and an inverter model name. [Effects of the Invention]

[0028] According to the above-described embodiment of the present invention, it is possible to minimize the costs incurred by the user during the long-term operation of the energy storage system. [Brief explanation of the drawings]

[0029] [Figure 1] 1 is a block diagram of an energy storage system to which the present invention can be applied. [Figure 2] 1 illustrates an example of an energy storage system to which the present invention can be applied. [Figure 3] FIG. 2 is a flow chart of an operation support method for an energy storage system according to an embodiment of the present invention. [Figure 4] 1 is a reference table illustrating battery information and inverter information according to an embodiment of the present invention. [Figure 5] 1 is a reference table illustrating a method for deriving a battery-inverter combination according to an embodiment of the present invention. [Figure 6] 1 is a reference table for explaining a method for deriving an optimal combination according to an embodiment of the present invention. [Figure 7] 1 is a block diagram of an operation support device for an energy storage system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0030] Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, it is understood that this is not intended to limit the present invention to the specific embodiments, but rather to include all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. Like reference numerals are used to refer to like elements throughout the drawings.

[0031] Terms such as "first," "second," "A," and "B" may be used to describe various components, but the components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be termed a "second component," and similarly, a second component may be termed a "first component," without departing from the scope of the present invention. The term "and / or" includes a combination of multiple associated listed items or any of multiple associated listed items.

[0032] When a component is referred to as being "coupled" or "connected" to another component, it is understood that the component may be directly coupled or connected to the other component, but that there may be other components in between. Conversely, when a component is referred to as being "directly coupled" or "directly connected" to another component, it is understood that there are no other components in between.

[0033] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly indicates otherwise. It should be understood that in this application, the terms "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and do not preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0034] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this invention pertains. Terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted as having an ideal or overly formal meaning unless expressly defined in this application.

[0035] Some terms used in this specification are defined as follows:

[0036] SOC (State of Charge) is the current charged state of the battery expressed as a percentage [%], and SOH (State of Health) is the current deterioration state of the battery expressed as a percentage [%].

[0037] The power limit is a limit on the amount of power that can be output, which is set in advance by the battery manufacturer according to the battery condition or according to the SOC. The power limit can be divided into a charge output limit and a discharge output limit depending on whether it is charging or discharging.

[0038] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0039] FIG. 1 is a block diagram of an energy storage system to which the present invention can be applied.

[0040] The energy storage system 100 is electrically connected to the power generation device 300 and the power grid 400, and can receive power from the power generation device 300 and the power grid 400 and store the power therein.

[0041] The energy storage system 100 is electrically connected to a load 200 and can supply the power stored therein to the load 200. Meanwhile, the load 200 is electrically connected to a power generation device 300 and a power grid 400 and can receive power from the power generation device 300 and the power grid 400.

[0042] The power generation device 300 is a device that generates electricity using a power generation device, and may be configured to include at least one of a power generation device that uses sunlight, solar heat, wind power, and geothermal power. However, the type of the power generation device 300 is not an essential component of the present invention, and the scope of the present invention is not limited to these individual devices.

[0043] The energy storage system 100 may be configured to be connected to a user terminal 600 through a network and transmit and receive data to and from the user terminal 600. For example, if the energy storage system 100 is a residential ESS, the user terminal 600 may be configured to be connected to a Home Energy Management System (HEMS), which is a top-level control system of the residential ESS, through a network and transmit and receive data to and from the user terminal 600.

[0044] The user terminal 600 is a computing device used by the owner or manager of the energy storage system 100, and may be, for example, a personal computer (PC), a mobile phone, or a tablet PC.

[0045] The energy storage system 100 may transmit information regarding one or more of an operating state of the energy storage system 100, a power generation state of the power generation device 300, and a power consumption state of the load 200 to the user terminal 600. Here, the user terminal 600 may be configured to output the received information via a predefined GUI (Graphical User Interface).

[0046] The user terminal 600 transmits a selection signal input by a user to the energy storage system 100, and the energy storage system 100 may be configured to perform a control operation corresponding to the selection signal. For example, if an off request signal for a specific load is received through the user terminal 600, the EMS of the energy storage system 100 may cut off the electrical path to the load to cut off the power supply to the load.

[0047] The operation support device 500 may be configured to be connected to the energy storage system 100 through a network to transmit and receive data to and from the energy storage system 100. The operation support device 500 may also be configured to be connected to one or more of the power generation device 300 and the user terminal 600 through a network to transmit and receive data to and from the energy storage system 100.

[0048] The operation support device 500 may be configured to be included within the energy storage system 100, or may be separately provided outside the energy storage system 100. For example, the operation support device 500 may be embodied as being included in a HEMS of a residential ESS, or may be embodied as being included in a server of an ESS management company.

[0049] The operation support device 500 may collect information on batteries and inverters applicable to the energy storage system 100 and generate recommended combination information of batteries and inverters that can minimize the operation cost of the energy storage system. Here, the operation support device 500 may provide the generated recommended combination information to one or more of the energy storage system 100 and the user terminal 600. Meanwhile, a method for generating recommended combination information will be described in detail later.

[0050] The operation support device 500 may monitor one or more of the operating state of the energy storage system 100, the power generation state of the power generation device 300, and the power consumption state of the load 200, and create an operation schedule that minimizes the power purchase cost of the energy storage system 100. Here, the operation schedule may include the charge / discharge amount of the battery for each time interval. The operation support device 500 may transmit the created operation schedule to the battery charge / discharge control device of the energy storage system 100, so that the battery of the energy storage system 100 may be controlled to be charged / discharged according to the operation schedule.

[0051] FIG. 2 shows an embodiment of an energy storage system to which the present invention can be applied.

[0052] Referring to FIG. 2, the energy storage system 100 may include a battery 110 for storing power, an inverter 120 for controlling the charging and discharging operation of the battery 110, and an EMS 130 for integrally managing the configuration of the energy storage system and power devices connected to the energy storage system.

[0053] The battery 110, which serves to store power, may be embodied in a form in which a number of battery packs constitute a battery rack, and a number of battery racks constitute a battery bank. Here, the battery pack may also be called a battery module depending on the device or system in which the battery is used.

[0054] Each battery may be provided with a Battery Management System (BMS), which monitors the current, voltage, and temperature of each battery rack (or pack) under its control, calculates the SOC (Status of Charge) based on the monitoring results, and controls charging and discharging.

[0055] The inverter 120 is also called a power conditioning system (PCS) or a power conversion system (PCS), and can control the power supplied from the outside to the battery and the power supplied from the battery to the outside.

[0056] The inverter 120 may include a power management system (PMS), and the operation support device 500 may be configured to work in conjunction with the power management system of the inverter 120 to transmit and receive data to and from the power management system.

[0057] The inverter 120 may control the charging and discharging operation of the battery 110 according to an operation schedule provided by the operation support device 500. For example, the inverter 120 may receive an operation schedule for a specific day from the operation support device 500 and control the charging and discharging operation of the battery 110 according to reference power for each time interval included in the operation schedule.

[0058] The EMS 130 can interface with the loads, generators, and inverters to monitor and control the associated configurations.

[0059] The PV system may include a PV module 310 (e.g., a solar panel) and a PV inverter 320, which is an AC / DC inverter, and may be configured such that the AC terminals of the PV inverter 320 and the AC terminals of the inverter 120 of the energy storage system are connected to an AC link.

[0060] The loads may include a general load 210 inside the house and an EV charging station 220. The EV charging station 220 is a system for charging an electric vehicle, and may be configured to receive power for charging the electric vehicle from an AC link.

[0061] The energy storage system shown in Figure 2 is an AC-coupled ESS in which the PV system, the load, and the energy storage system are connected over an AC link.

[0062] If the energy storage system has an AC-coupled structure, the operation support device 500 can work in conjunction with one or more of the inverter 120, the PV inverter 320, and the EMS 130 to collect basic information for generating recommended combination information.

[0063] Meanwhile, the present invention can also be applied to a DC-coupled ESS in which the output side of the PV system and the output side of the battery are connected via a DC link, and the DC link is connected to one terminal of the inverter. When the energy storage system has a DC-coupled structure, the PV inverter 320 is omitted, and the operation support device 500 can collect basic information for generating recommended combination information in conjunction with one or more of the inverter 120 and the EMS 130.

[0064] FIG. 3 is a flowchart of an operation support method for an energy storage system according to an embodiment of the present invention.

[0065] The method for supporting operation of an energy storage system according to an embodiment of the present invention may be performed by an operation support device that is linked to the energy storage system.

[0066] The operation support device may collect information about a battery and an inverter that can be applied to the energy storage system (S310). Here, the operation support device may check the battery information and the inverter information from one or more of a storage device, an external storage device connected by an administrator, and a user terminal.

[0067] The information about the batteries may include one or more of a model name, a capacity, a threshold SOC range, and a purchase cost for each of the one or more batteries, and the information about the inverters may include one or more of a model name, a limit power output, and a purchase cost for each of the one or more inverters.

[0068] FIG. 4 is a reference table for explaining battery information and inverter information according to an embodiment of the present invention.

[0069] Referring to FIG. 4(A), the operational support device can collect a battery list including the model name (or identifier), capacity, SOC lower limit, SOC upper limit, and purchase cost for each of a plurality of batteries that can be applied to the energy storage system.

[0070] Referring to FIG. 4(B), the operation support device can collect an inverter list including the model name (or identifier), capacity, battery voltage information, charge output limit, discharge output limit, and purchase cost for each of a plurality of inverters that can be applied to the energy storage system.

[0071] The operation support device can receive model name information of the battery system from the energy storage system or the user terminal, and determine the batteries and inverters applicable to the energy storage system based on the received model name information.

[0072] 3, the operation support device can derive multiple battery-inverter combinations based on the design structure of the energy storage system (S320). Here, the battery-inverter combinations can be composed of one or more batteries and inverters.

[0073] FIG. 5 is a lookup table illustrating a method for deriving a battery-inverter combination according to an embodiment of the present invention.

[0074] For example, if the design structure of the energy storage system allows three to five series-connected batteries to be connected to one inverter, and it is confirmed that there are five inverter model names (Inv #1 to #5) that can be applied to the energy storage system, the operation support device can derive a total of 15 battery-inverter combinations (C #1 to #15), as shown in Figure 5. The 15 combinations derived in the above example are, as shown in Figure 5, [3 batteries, Inv #1], [3 batteries, Inv #2], [3 batteries, Inv #3], [3 batteries, Inv #4], [3 batteries, Inv #5], [4 batteries, Inv #1], [4 batteries, Inv #2], [4 batteries, Inv #3], [4 batteries, Inv #4], [4 batteries, Inv #5], [5 batteries, Inv #1], [5 batteries, Inv #2], [5 batteries, Inv #3], [5 batteries, Inv #4], and [5 batteries, Inv #5].

[0075] In an embodiment, the operation support device may derive a range of the number of batteries applicable to the energy storage system based on the capacity of the batteries and the limit output of the inverter. For example, the number of batteries may be determined as a range such that the total capacity of the combined batteries exceeds the minimum guaranteed capacity of the energy storage system and is less than the limit capacity according to the limit output of the inverter.

[0076] 3, the operation support device can calculate the operating cost of the energy storage system for each of the combinations derived in S320 (S330). Here, the operating cost of the energy storage system can be calculated based on the grid power purchase cost and the battery and inverter purchase costs.

[0077] Thereafter, the operation support device derives the combination that shows the lowest operation cost from among the combinations (S340), and can determine the derived combination as the optimal combination.

[0078] FIG. 6 is a look-up table for explaining a method for deriving an optimal combination according to an embodiment of the present invention.

[0079] 6, the operations support device can calculate the grid power purchase cost and the battery and inverter purchase cost for each of the 15 battery-inverter combinations (C #1 to #15) derived in S330. The operations support device can then add up the grid power purchase cost and the battery and inverter purchase cost to calculate the total operating cost for each battery-inverter combination. Here, the operations support device can determine the [4 batteries, Inv #3] (C #8) that shows the lowest total operating cost among the 15 combinations as the optimal combination.

[0080] In an embodiment, the operating cost of the energy storage system can be calculated as the sum of the grid power purchase cost (C_p) and the battery and inverter purchase cost (C_bi) (C_t = C_p + C_bi), as shown in FIG. 6 .

[0081] In another embodiment, the operating cost of the energy storage system can be calculated as the sum (C_t = a*C_p + b*C_bi) of a value reflecting a predefined weighting factor (a) on the grid power purchase cost (C_p) and a value reflecting a predefined weighting factor (b) on the battery and inverter purchase cost (C_bi).

[0082] In another embodiment, the operating cost of the energy storage system can be calculated as the product of the grid power purchase cost (C_p) reflected by a predefined weighting factor (a) and the battery and inverter purchase cost (C_bi) reflected by a predefined weighting factor (b) (C_t = a*C_p * b*C_bi).

[0083] That is, the operating cost of the energy storage system can be calculated in various ways as needed.

[0084] 3 , in S330, the operation support device may calculate the grid power purchase cost for a predetermined period for each combination derived in S320 based on historical information about one or more of the energy storage system, the load, and the power generation device. Here, the operation support device may receive historical information about a certain period from one or more of the user terminal 600, the EMS 130, the inverter 120, the EV station 220, and the PV inverter 320.

[0085] The past history information may include one or more of power consumption status information of the load (e.g., power consumption per unit of time), power generation status information of the power generation device (e.g., power generation per unit of time), and battery charge / discharge schedule information (e.g., charge / discharge amount per unit of time).

[0086] The operation support device may perform a simulation using historical information for an energy storage system using a battery and an inverter according to each combination (C #1 to #15). Then, the operation support device may calculate a grid power purchase cost for each combination for a preset period (e.g., one month) based on the grid power usage amount per hour and grid power cost information per hour derived as a result of the simulation.

[0087] In an embodiment, the operation support device derives an operation schedule (charge / discharge amount per unit time) of the battery that minimizes the cost of purchasing grid power based on historical information regarding the load and the power generation device, and can calculate the cost of purchasing grid power using the derived operation schedule.

[0088] Specifically, the operation support device can collect information on the power generation state and the power consumption state for a certain past period (e.g., the past year), and then derive an operation schedule for a certain period (e.g., one day) that minimizes the grid power purchase cost using an objective function defined as the grid power purchase cost.

[0089] The operation control device can derive an operation schedule using an objective function defined based on MILP (Mixed-integer Linear Programming). Hereinafter, a specific example of a method for generating such an operation schedule will be described in detail.

[0090] The operation control device may derive an operation schedule including the charge / discharge amount of the battery for each time interval using an objective function defined as the purchase cost of grid power. Here, the objective function may be defined as Equation 1 below.

[0091]

number

[0092] (where Pgrid(t) is the grid power schedule and λgrid(t) is the grid power cost.)

[0093] Equation 1 is an objective function for deriving the charge or discharge amount of a battery for each time interval that can minimize the grid power purchase cost. Here, the objective function according to Equation 1 can define constraints including at least one of a first condition related to the balance between power supply and power consumption, a second condition related to the state of charge (SOC) according to the battery charge / discharge efficiency, a third condition related to the battery's limit charge amount, a fourth condition related to the limit output of the power conversion device, and a fifth condition related to the binarization of the state of charge and the state of discharge.

[0094]

number

[0095] (Here, PBatch(t) is the amount of charge power of the battery, PBatdch(t) is the amount of discharge power of the battery, Ppv(t) is the amount of power generated, and Pload(t) is the amount of power consumed.)

[0096]

number

[0097] (where SOC(t) is the SOC of the battery, Ecap is the capacity of the battery, ηch is the charging efficiency of the power converter, ηdch is the discharging efficiency of the power converter, and tstep is the time interval.)

[0098]

number

[0099] (Here, SOCmin is the lower limit of SOC, and SOCmax is the upper limit of SOC.)

[0100]

number

[0101] (where μch is the battery state for charging, which has a value of 0 or 1, and Pinv_max is the maximum output of the inverter.)

[0102]

number

[0103] (where μdch is the battery state for discharging, which has a value of 0 or 1.)

[0104]

number

[0105] The first condition can be embodied in Equation 2, where the decision variables PBatch(t) and PBatdch(t) are determined according to the balance between power supply and demand. Meanwhile, in Equation 2, Ppv(t) and Pload(t) can be applied to the power generation amount per hour and the power consumption amount per hour based on past history information.

[0106] Meanwhile, when the collected history information includes power consumption state information for each of a plurality of loads, Equation 2 can be transformed into Equation 8 below.

[0107]

number

[0108] (Here, Pflexible load(t) is the power consumption of the load that can be turned on and off, Pnonflexible load(t) is the power consumption of the load that cannot be turned on and off, and PEV(T) is the power consumption of the EV charging station.)

[0109] That is, some terms may be added or deleted from the formula for the first condition regarding the balance between power supply and power consumption in accordance with the power consumption state information included in the past history information.

[0110] The second condition can be embodied in Equation 3, and functions such that the SOC in the next time interval is determined based on the battery capacity and charge / discharge efficiency.

[0111] The third condition can be embodied in Equation 4, and functions to determine the SOC within a set threshold range.

[0112] The fourth and fifth conditions can be embodied in Equations 5 to 7, and function to prevent the decision variables PBatch(t) and PBatdch(t) from exceeding the output capacity of the inverter, while simultaneously preventing the amount of charging power and the amount of discharging power from being determined simultaneously.

[0113] The operation control device can derive PBatch(t) and PBatdch(t) that satisfy the above objective function and constraint conditions, and generate an operation schedule that includes them.

[0114] The operation support device can perform a simulation using historical information on power consumption and power generation and the generated operation schedule for an energy storage system using batteries and inverters according to each combination (C #1 to #15).The operation support device can then calculate the grid power purchase cost for each combination for a preset period (e.g., one month) based on the grid power usage amount by time unit and grid power cost information by time unit derived as a result of the simulation.

[0115] If the optimal combination showing the lowest operating cost is determined in S340, the operation support device may generate recommended combination information including information about the optimal combination (S350). Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, the battery connection structure, and the inverter model name. For example, the recommended combination information may be embodied as [4 batteries, series connection, Inv 9801].

[0116] The operation support device can provide the recommended combination information generated in S350 to the user terminal (S360). Here, the user terminal can output the received recommended combination information via a predefined GUI.

[0117] In an embodiment, the operation support device may provide an optimal combination and a corresponding optimal operation schedule to a user terminal, an EMS, or an inverter. Here, the optimal operation schedule may correspond to an operation schedule derived based on an objective function and constraints when calculating the grid power purchase cost of the optimal combination. That is, when an optimal battery-inverter combination is applied to a future energy storage system, the operation support device may provide the recommended combination and the corresponding optimal operation schedule as a reference operation schedule so that the grid power purchase cost is minimized when the energy storage system is operated with the combination.

[0118] FIG. 7 is a block diagram of an operation support device for an energy storage system according to an embodiment of the present invention.

[0119] The operation support device 500 according to an embodiment of the present invention may be configured to be included in an energy storage system or may be separately provided outside the energy storage system. For example, the operation support device 500 may be implemented as being included in a Home Energy Management System (HEMS), which is a top-level control system for a residential ESS, or may be implemented as being included in a server of an ESS management company.

[0120] The operation support device 500 may include at least one processor 510, a memory 520 that stores at least one instruction executed by the processor, and a transceiver device 530 that is connected to a network for communication.

[0121] The at least one instruction may include an instruction to collect information on batteries and inverters that can be applied to the energy storage system; an instruction to derive a plurality of combinations, each consisting of one or more batteries and inverters, based on the structure of the energy storage system; an instruction to calculate the operating cost of the energy storage system for each of the combinations; and an instruction to generate recommended combination information including information on the combination that shows the lowest operating cost among the combinations.

[0122] The instructions to collect information about the batteries and inverters may include instructions to collect one or more of the model name, capacity, threshold SOC range, and purchase cost for each of the batteries, and the model name, power limit, and purchase cost for each of the inverters.

[0123] The instruction to derive the plurality of combinations may include an instruction to derive a range of battery numbers based on the battery capacity and the inverter output limit; and an instruction to derive a plurality of combinations applicable to the energy storage system based on the range of battery numbers and the design structure of the battery system.

[0124] The instructions for calculating the operating costs of the energy storage system may include instructions for calculating a grid power purchase cost and a battery and inverter purchase cost for each of the combinations; and instructions for calculating the operating costs based on the grid power purchase cost and the battery and inverter purchase cost.

[0125] The instructions for calculating the operating cost of the energy storage system may include instructions for calculating a grid power purchase cost for a predetermined period for each of the combinations based on historical information regarding one or more of the energy storage system, a load associated with the energy storage system, and a power generation device associated with the energy storage system.

[0126] The instruction to calculate the grid power purchase cost may include an instruction to collect information on the power consumption state of the load and information on the power generation state of the power generation device; an instruction to derive an operation schedule including charge / discharge amounts for each time interval that minimizes the grid power purchase cost using an objective function defined as the grid power purchase cost; and an instruction to apply the operation schedule and grid power cost information to the energy storage system according to each of the combinations to calculate the grid power purchase cost for a predetermined period for each of the combinations.

[0127] Here, the objective function can define constraints including at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the battery's charge / discharge efficiency, a third condition regarding the battery's limit charge amount, a fourth condition regarding the inverter's limit output, and a fifth condition regarding the binarization of the charge state and discharge state.

[0128] The at least one instruction may further include an instruction to provide the generated recommended combination information to a user terminal that interfaces with the energy storage system.

[0129] Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, a battery connection structure, and an inverter model name.

[0130] The operation support device 500 may further include an input interface device 540, an output interface device 550, a storage device 560, etc. The components included in the operation support device 500 are connected by a bus 570 to communicate with each other.

[0131] Here, the processor 510 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the method according to the embodiment of the present invention is performed. The memory (or storage device) may be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory may be composed of at least one of a read-only memory (ROM) and a random access memory (RAM).

[0132] The operations of the methods according to the embodiments of the present invention can be embodied as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all kinds of storage devices in which data that can be read by a computer system is stored. In addition, the computer-readable recording medium can be distributed among computer systems connected via a network, so that the computer-readable program or code can be stored and executed in a distributed manner.

[0133] Some aspects of the invention have been described in the context of an apparatus, but they may also be described in terms of a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may be described in terms of a corresponding block or item or feature of a corresponding apparatus. Some or all of the method steps may be performed by (or using) a hardware apparatus, such as a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps may be performed by such an apparatus.

[0134] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art will understand that various modifications and variations can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the following claims. [Explanation of symbols]

[0135] 100: Energy storage system 200: Load 300: Power generation equipment 400: Power grid 500: Operation support equipment 600: User terminal

Claims

1. An operation support device for an energy storage system, at least one processor; and a memory for storing at least one instruction to be executed by said at least one processor; The at least one instruction: instructions to collect information regarding batteries and inverters that may be applied to the energy storage system; instructions for deriving a plurality of combinations, each of which comprises one or more batteries and an inverter, based on a configuration of the energy storage system; instructions for calculating an operating cost of an energy storage system for each of said combinations; and An operation support device including an instruction to generate recommended combination information including information about a combination that shows the lowest operation cost among the combinations.

2. The instructions for collecting information about the battery and the inverter include:

2. The operational support device of claim 1, further comprising instructions to collect one or more of the model name, capacity, threshold SOC range, and purchase cost for each battery, and the model name, limit power output, and purchase cost for each inverter.

3. The instruction to derive the plurality of combinations includes: instructions for deriving a range of battery numbers based on the capacity of the batteries and the limiting power output of the inverter; and The operation support device according to claim 1 , further comprising an instruction to derive a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and a design structure of the battery system.

4. The instructions for calculating an operating cost of the energy storage system include: instructions for calculating grid power purchase costs and battery and inverter purchase costs for each of said combinations; and The operation support device of claim 1 , further comprising instructions for calculating the operating cost based on the grid power purchase cost and the battery and inverter purchase cost.

5. The instructions for calculating an operating cost of the energy storage system include:

5. The operation support device of claim 4, further comprising instructions for calculating a grid power purchase cost for a preset period for each of the combinations based on historical information regarding one or more of the energy storage system, a load coupled to the energy storage system, and a power generation device coupled to the energy storage system.

6. The instructions to calculate the grid power purchase cost include: instructions to collect information regarding a power consumption state of the load and information regarding a power generation state of the power generation device; An instruction to derive an operation schedule including charge / discharge amounts for each time interval, which minimizes the grid power purchase cost using an objective function defined as the grid power purchase cost; and 6. The operation support device of claim 5, further comprising instructions for applying the operation schedule and grid power cost information to an energy storage system according to each of the combinations to calculate a grid power purchase cost for a preset period for each of the combinations.

7. The objective function is:

7. The operational support device of claim 6, wherein constraint conditions are defined that include at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the battery's charge / discharge efficiency, a third condition regarding the battery's limit charge amount, a fourth condition regarding the inverter's limit output, and a fifth condition regarding the binarization of the charge state and discharge state.

8. The operation support device according to claim 1 , further comprising an instruction to provide the generated recommended combination information to a user terminal that interfaces with the energy storage system.

9. The recommended combination information includes: The operation support device according to claim 8 , comprising one or more of the number of batteries applied to the energy storage system, a battery connection structure, and an inverter model name.

10. An operation support method for an energy storage system, comprising: collecting information about batteries and inverters that can be applied to the energy storage system; deriving a plurality of combinations, each of which includes one or more batteries and an inverter, based on a structure of the energy storage system; calculating an operating cost of the energy storage system for each of the combinations; and An operation support method comprising the step of generating recommended combination information including information about a combination among the combinations that shows the lowest operation cost.

11. collecting information about the battery and the inverter, 11. The operation support method according to claim 10, further comprising the step of collecting one or more of the model name, capacity, threshold SOC range and purchase cost for each battery, and the model name, limit output and purchase cost for each inverter.

12. The step of deriving a plurality of combinations includes: Deriving a range of the number of batteries based on the capacity of the batteries and the limit output of the inverter; and The operation support method according to claim 10 , further comprising the step of deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and a design structure of the battery system.

13. The step of calculating an operating cost of the energy storage system includes: calculating grid power purchase costs and battery and inverter purchase costs for each of the combinations; and The operation support method according to claim 10 , further comprising the step of calculating the operation cost based on the grid power purchase cost and the battery and inverter purchase costs.

14. The step of calculating an operating cost of the energy storage system includes:

14. The operation support method according to claim 13, further comprising: calculating a grid power purchase cost for a preset period for each of the combinations based on past history information regarding one or more of the energy storage system, a load coupled to the energy storage system, and a power generation device coupled to the energy storage system.

15. The step of calculating the grid power purchase cost includes: collecting information about the power consumption state of the load and information about the power generation state of the power generation device; A step of deriving an operation schedule including charge / discharge amounts for each time interval that minimizes the grid power purchase cost using an objective function defined as the grid power purchase cost; and 15. The operation support method according to claim 14, further comprising: applying the operation schedule and grid power cost information to an energy storage system according to each of the combinations to calculate a grid power purchase cost for a predetermined period for each of the combinations.

16. The objective function is: The operational support method of claim 15, wherein constraint conditions are defined that include at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the battery's charge / discharge efficiency, a third condition regarding the battery's limit charge amount, a fourth condition regarding the inverter's limit output, and a fifth condition regarding the binarization of the charge state and discharge state.

17. The operation support method according to claim 10 , further comprising an instruction to provide the generated recommended combination information to a user terminal that interfaces with the energy storage system.

18. The recommended combination information includes: The operation support method according to claim 17 , including one or more of the number of batteries applied to the energy storage system, a battery connection structure, and an inverter model name.

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