Operation support device and method of energy storage system

Abstract

An operation support device according to an embodiment of the present invention is an operation support device of an energy storage system, and may comprise: at least one processor; and a memory for storing at least one command executed through the at least one processor. The at least one command may include commands to: collect information on a battery and an inverter which can be applied to the energy storage system; derive a plurality of combinations each composed of one or more batteries and inverters on the basis of the structure of the energy storage system; calculate an operating cost of the energy storage system for each of the combinations; and generate recommended combination information including information on a combination having a minimum operating cost among the combinations.

Description

Device and method for supporting operation of energy storage system

[0001] This application claims the benefit of Korean Patent Application No. 10-2023-0092219 filed with the Korean Intellectual Property Office on July 17, 2023, the entire disclosure of which is 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 helps minimize the operation cost of an energy storage system.

[0003] Energy Storage Systems (ESS) utilize batteries that store energy and operate in conjunction with renewable energy sources and the power grid. With the recent expansion of smart grids and renewable energy sources, coupled with an emphasis on power grid efficiency and stability, demand for energy storage systems is steadily increasing to regulate power supply and demand and improve power quality. Depending on the intended use, energy storage systems can vary in output and capacity. Multiple battery systems can be interconnected to form large-capacity energy storage systems.

[0004] Among ESS, ESS linked to PV (Photovoltaic; solar power generation) systems is becoming increasingly widespread. PV-linked ESS is configured to appropriately distribute power supplied from the power grid and power generated by PV systems to supply loads, storing any remaining power in a battery system.

[0005] The most important goal for ESS users is minimizing their operating costs. These costs, which arise during ESS operation, consist of the purchase cost of grid power, which must be paid periodically, and the battery replacement cost, which occurs at each battery replacement cycle. Typically, ESS is controlled by considering various factors, such as the PV system's power generation, the load's power demand, and the battery's state of charge. However, conventional technologies focus on ESS control methods to improve power efficiency or battery performance, limiting their ability to minimize user costs from a long-term perspective.

[0006] Accordingly, there is a need for appropriate energy storage system operation support technology that can help minimize long-term operating costs of energy storage systems.

[0007] The purpose of the present invention to solve the above problems is to provide an operation support device for an energy storage system that helps minimize the operating 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.

[0009] An operation support device according to one embodiment of the present invention for achieving the above purpose may include an operation support device of an energy storage system, which may include at least one processor and a memory that stores at least one command executed through the at least one processor.

[0010] The at least one command may include: a command for collecting information about batteries and inverters applicable to the energy storage system; a command for deriving a plurality of combinations, each combination comprising one or more batteries and inverters, based on the structure of the energy storage system; a command for calculating an operating cost of the energy storage system for each of the combinations; and a command for generating recommended combination information including information about a combination exhibiting the lowest operating cost among the combinations.

[0011] The command for collecting information about the battery and inverter may include a command for collecting one or more of the model name, capacity, critical SOC range, and purchase cost for each battery, and the model name, limit output, and purchase cost for each inverter.

[0012] The command for deriving the plurality of combinations may include a command for deriving a range of the number of batteries based on the capacity of the batteries and the limit output of the inverter; and a command for deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and the design structure of the battery system.

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

[0014] The command for calculating the operating cost of the energy storage system may include a command for calculating a system power purchase cost for a preset period for each of the combinations based on past history information about at least one of the energy storage system, a load linked to the energy storage system, and a power generation device linked to the energy storage system.

[0015] The command for calculating the system power purchase cost may include: a command for collecting information on the power consumption status of the load and information on the power production status of the power generation device; a command for deriving an operation schedule including a charge / discharge amount for each time interval that minimizes the system power purchase cost by using an objective function defined as the system power purchase cost; and a command for calculating the system power purchase cost for a preset period for each of the combinations by applying the operation schedule and system power cost information to an energy storage system according to each of the combinations.

[0016] Here, the objective function may be defined as a constraint including at least one of a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the inverter, and a fifth condition regarding the binarization of the charge state and the discharge state.

[0017] The at least one command may further include a command for providing the generated recommended combination information to a user terminal linked to 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, the connection structure of the batteries, and the model name of the inverter.

[0019]

[0020] According to an embodiment of the present invention for achieving the above another object, an operation support method is provided as an operation support method of an energy storage system, which may include: a step of collecting information on a battery and an inverter applicable to the energy storage system; a step of deriving a plurality of combinations, each combination including one or more batteries and an inverter, based on a structure of the energy storage system; a step of calculating an operation cost of the energy storage system for each of the combinations; and a step of generating recommended combination information including information on a combination exhibiting the minimum operation cost among the combinations.

[0021] The step of collecting information about the battery and inverter may include a step of collecting at least one of a model name, a capacity, a critical SOC range, and a purchase cost for each battery, and a model name, a limit output, and a purchase cost for each inverter.

[0022] The step of deriving the plurality of combinations may include a step of deriving a range of the number of batteries based on the capacity of the batteries and the limit output of the inverter; and a step of deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and the design structure of the battery system.

[0023] The step of calculating the operating cost of the energy storage system may include the step of calculating the system power purchase cost and the battery and inverter purchase cost for each of the combinations; and the step of calculating the operating cost based on the system power purchase cost and the battery and inverter purchase cost.

[0024] The step of calculating the operating cost of the energy storage system may include a step of calculating a system power purchase cost for a preset period for each of the combinations based on past history information about at least one of the energy storage system, a load linked to the energy storage system, and a power generation device linked to the energy storage system.

[0025] The step of calculating the system power purchase cost may include the steps of collecting information on the power consumption status of the load and information on the power production status of the power generation device; using an objective function defined as the system power purchase cost, deriving an operation schedule including a charge / discharge amount for each time interval that minimizes the system power purchase cost; and applying the operation schedule and system power cost information to an energy storage system according to each of the combinations, calculating the system power purchase cost for a preset period for each of the combinations.

[0026] Here, the objective function may be defined as a constraint including at least one of a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the inverter, and a fifth condition regarding the binarization of the charge state and the discharge state.

[0027] The above operation support method may further include a command for providing the generated recommended combination information to a user terminal linked with the energy storage system.

[0028] Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, the connection structure of the batteries, and the model name of the inverter.

[0029] According to the above-described embodiment of the present invention, it is possible to minimize user costs incurred during long-term operation of an energy storage system.

[0030] Figure 1 is a block diagram of an energy storage system to which the present invention can be applied.

[0031] Figure 2 shows an implementation example of an energy storage system to which the present invention can be applied.

[0032] Figure 3 is a flowchart of a method for supporting operation of an energy storage system according to an embodiment of the present invention.

[0033] Figure 4 is a reference table for explaining battery information and inverter information according to an embodiment of the present invention.

[0034] FIG. 5 is a reference table for explaining a method for deriving battery-inverter combinations according to an embodiment of the present invention.

[0035] Figure 6 is a reference table for explaining a method for deriving an optimal combination according to an embodiment of the present invention.

[0036] Figure 7 is a block diagram of an operation support device of an energy storage system according to an embodiment of the present invention.

[0037] 100: Energy storage system

[0038] 200: Subordinate

[0039] 300: Power generation device

[0040] 400: Power system

[0041] 500: Operational Support Device

[0042] 600: User terminal

[0043] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. Throughout the description of each drawing, similar reference numerals have been used to designate similar components.

[0044] Terms such as "first," "second," "A," and "B" may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, the first component could be referred to as the "second component," and similarly, the second component could also be referred to as the "first component." The term "and / or" includes any combination of multiple related items listed or any one of multiple related items listed.

[0045] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0046] The terminology used in this application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, it should be understood that the terms "comprise" or "have" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0047] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0048]

[0049] Some terms used in this specification are defined as follows:

[0050] 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 [%].

[0051] Power Limit (PL) refers to the output power limit, which is preset by the battery manufacturer based on battery condition or set based on the SOC. Power limits can be categorized into charge power limits and discharge power limits, depending on whether the battery is being charged or discharged.

[0052]

[0053] Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the attached drawings.

[0054]

[0055] Figure 1 is a block diagram of an energy storage system to which the present invention can be applied.

[0056] The energy storage system (100) is electrically connected to a power generation device (300) and a power system (400), and can receive power from the power generation device (300) and the power system (400) and store it internally.

[0057] The energy storage system (100) is electrically connected to a load (200) and can supply power stored therein to the load (200). Meanwhile, the load (200) is electrically connected to a power generation device (300) and a power system (400) and can receive power from the power generation device (300) and the power system (400).

[0058] The power generation device (300) is a device that generates power using a power generation device, and may be configured to include at least one of a solar power generation device, a solar thermal power generation device, a wind power generation device, and a geothermal power generation device. Meanwhile, since the type of the power generation device (300) is not an essential component of the present invention, the scope of the present invention is not limited to these entities.

[0059] The energy storage system (100) may be configured to be connected to a user terminal (600) via a network and to mutually transmit and receive data. For example, if the energy storage system (100) is a residential ESS, the user terminal (600) may be configured to be connected to a HEMS (Home Energy Management System), which is the top-level control system of the residential ESS, via a network and to mutually transmit and receive data.

[0060] The user terminal (600) is a computing device used by the owner or manager of the energy storage system (100), and may correspond to, for example, a personal computer (PC), a mobile phone, or a tablet PC.

[0061] The energy storage system (100) can transmit information regarding one or more of the operating status of the energy storage system (100), the power generation status of the power generation device (300), and the power consumption status of the load (200) to the user terminal (600). Here, the user terminal (600) can be configured to output the received information through a predefined GUI (Graphical User Interface).

[0062] The user terminal (600) may be configured to transmit a selection signal input by the 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, when an off request signal for a specific load is received through the user terminal (600), the EMS of the energy storage system (100) may block the electrical path for the load, thereby blocking the power supply to the load.

[0063] The operation support device (500) may be configured to be connected to the energy storage system (100) via a network and to mutually transmit and receive data. In addition, the operation support device (500) may be configured to be connected to one or more of the power generation device (300) and the user terminal (600) via a network and to mutually transmit and receive data.

[0064] The operation support device (500) may be configured and 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 implemented and included in the HEMS of a residential ESS, or may be implemented and included in the server of an ESS management company.

[0065] The operation support device (500) can collect information regarding batteries and inverters applicable to the energy storage system (100) and generate recommended combination information of batteries and inverters that can minimize the operating costs of the energy storage system. Here, the operation support device (500) can provide the generated recommended combination information to one or more of the energy storage system (100) and the user terminal (600). Meanwhile, details regarding the method for generating the recommended combination information will be described later.

[0066] The operation support device (500) can monitor one or more of the operating status of the energy storage system (100), the power generation status of the power generation device (300), and the power consumption status of the load (200), and can establish an operation schedule that can minimize the power purchase cost of the energy storage system (100). Here, the operation schedule can include the charge and discharge amount of the battery for each time period. The operation support device (500) can transmit the established operation schedule to the battery charge and discharge control device of the energy storage system (100), thereby allowing the battery of the energy storage system (100) to be charged and discharged according to the operation schedule.

[0067]

[0068] Figure 2 shows an implementation example of an energy storage system to which the present invention can be applied.

[0069] Referring to FIG. 2, an energy storage system (100) may be configured to include a battery (110) that stores power, an inverter (120) that controls the charging and discharging operation of the battery (110), and an EMS (130) that integrates and manages the configurations of the energy storage system and power devices linked to the energy storage system.

[0070] A battery (110) that performs the role of storing power can be typically implemented in a form in which a plurality of battery packs form a battery rack, and a plurality of battery racks form a battery bank. Here, depending on the device or system in which the battery is used, the battery pack may also be referred to as a battery module.

[0071] Each battery can be equipped with a Battery Management System (BMS). The BMS monitors the current, voltage, and temperature of each battery rack (or pack) it manages, calculates the State of Charge (SOC) based on the monitoring results, and controls charging and discharging.

[0072] The inverter (120) is also referred to as a power conditioning system (PCS) or a power conversion system (PCS), and can control power supplied to the battery from the outside and power supplied from the battery to the outside.

[0073] The inverter (120) may include a power management system (PMS), and the operation support device (500) may be configured to be linked with the power management system of the inverter (120) to mutually transmit and receive data.

[0074] The inverter (120) can control the charging and discharging operation of the battery (110) according to an operating schedule by the operating support device (500). For example, the inverter (120) can receive an operating schedule for a specific day from the operating support device (500) and control the charging and discharging operation of the battery (110) according to the reference power for each time period included in the operating schedule.

[0075] EMS (130) can be linked with loads, power generation devices, and inverters, and monitor and control the linked components.

[0076] The PV system may be configured to include a PV module (310) (e.g., a solar panel) and a PV inverter (320) which is an AC / DC inverter, and the AC terminal of the PV inverter (320) and the AC terminal of the inverter (120) of the energy storage system may be connected to an AC link.

[0077] The load may be configured to include a general load (210) inside a house and an EV charging station (220). The EV charging station (220) is a system for charging electric vehicles and may be configured to receive power for charging electric vehicles from an AC link.

[0078] The energy storage system illustrated in Fig. 2 is an AC coupled ESS in which a PV system, a load, and an energy storage system are connected on an AC link.

[0079] When the energy storage system has an AC coupled structure, the operation support device (500) can collect basic information for generating recommended combination information by interfacing with one or more of the inverter (120), PV inverter (320), and EMS (130).

[0080] Meanwhile, the present invention is also applicable to a DC coupled ESS in which the output terminal of a PV system and the output terminal of a battery are connected via a DC link, and the DC link is connected to one terminal of an inverter. In the case of an energy storage system having a DC coupled structure, since the PV inverter (320) is omitted, the operation support device (500) can collect basic information for generating recommended combination information by interworking with at least one of the inverter (120) and the EMS (130).

[0081]

[0082] Figure 3 is a flowchart of a method for supporting operation of an energy storage system according to an embodiment of the present invention.

[0083] The operation support method of an energy storage system according to an embodiment of the present invention can be performed by an operation support device linked to the energy storage system.

[0084] The operation support device can collect information about batteries and inverters applicable to the energy storage system (S310). Here, the operation support device can check battery information and inverter information from one or more of the storage device, an external storage device connected by the administrator, and a user terminal.

[0085] Information about the batteries may include, for each of one or more batteries, one or more of the following: model name, capacity, critical SOC range, and purchase cost. Furthermore, information about the inverters may include, for each of one or more inverters, one or more of the following: model name, limit output, and purchase cost.

[0086] Figure 4 is a reference table for explaining battery information and inverter information according to an embodiment of the present invention.

[0087] Referring to FIG. 4(A), the operation support device can collect a battery list including a 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.

[0088] Referring to FIG. 4(B), the operation support device can collect an inverter list including a 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.

[0089] The operation support device can receive model information of a battery system from an energy storage system or a user terminal, and determine a battery and inverter applicable to the energy storage system based on the received model information.

[0090] Referring again to FIG. 3, the operation support device can derive multiple battery-inverter combinations based on the design structure of the energy storage system (S320). Here, a battery-inverter combination may be comprised of one or more batteries and an inverter.

[0091] FIG. 5 is a reference table for explaining a method for deriving battery-inverter combinations according to an embodiment of the present invention.

[0092] For example, in the design structure of an energy storage system, if 3 to 5 series-connected batteries can be connected to one inverter, and 5 inverter models (Inv #1 to #5) applicable to the energy storage system are identified, the operation support device can derive a total of 15 battery-inverter combinations (C #1 to #15), as illustrated in FIG. 5. The 15 combinations derived from the above example are [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], as shown in FIG. 5.

[0093] In an embodiment, the operating support device may derive a range of battery counts applicable to the energy storage system based on the battery capacity and the inverter's output limit. For example, the number of batteries may be determined such that the total capacity of the combined batteries exceeds the minimum guaranteed capacity of the energy storage system and falls below the limit capacity based on the inverter's output limit.

[0094] Referring again to FIG. 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 cost.

[0095] Thereafter, the operation support device can derive a combination that represents the minimum operation cost among the combinations (S340) and determine the combination as the optimal combination.

[0096] Figure 6 is a reference table for explaining a method for deriving an optimal combination according to an embodiment of the present invention.

[0097] Referring to FIG. 6, the operation support device can calculate the power system purchase cost and the battery and inverter purchase cost for each of the 15 battery-inverter combinations (C #1 to #15) derived from S330. Thereafter, the operation support device can calculate the total operation cost for each battery-inverter combination by adding the power system purchase cost and the battery and inverter purchase cost. Here, the operation support device can determine [4 batteries, Inv #3] (C #8) as the optimal combination, which has the lowest total operation cost among the 15 combinations.

[0098] 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 illustrated in FIG. 6.

[0099] In another embodiment, the operating cost of the energy storage system can be calculated as the sum of a value reflecting a predefined weighting factor (a) for the grid power purchase cost (C_p) and a value reflecting a predefined weighting factor (b) for the battery and inverter purchase cost (C_bi) (C_t = a*C_p + b*C_bi).

[0100] In another embodiment, the operating cost of the energy storage system can be calculated as a value (C_t = a*C_p * b*C_bi) that is the product of a value that reflects a predefined weighting factor (a) for the grid power purchase cost (C_p) and a value that reflects a predefined weighting factor (b) for the battery and inverter purchase cost (C_bi).

[0101] That is, the operating cost of an energy storage system can be calculated in various ways depending on the needs.

[0102] Referring back to FIG. 3, at S330, the operation support device may calculate a grid power purchase cost for a predetermined period of time for each of the combinations derived at S320 based on past history information for one or more of the energy storage system, load, and power generation device. Here, the operation support device may receive past history information for a predetermined period of time from one or more of the user terminal (600), the EMS (130), the inverter (120), the EV station (220), and the PV inverter (320).

[0103] The past history information may include one or more of power consumption status information of a load (e.g., power consumption per hour), power production status information of a power generation device (e.g., power production per hour), and charge / discharge schedule information of a battery (e.g., charge / discharge amount per hour).

[0104] The operation support device can conduct simulations using historical data for energy storage systems equipped with batteries and inverters for each combination (C #1 to #15). Then, based on the hourly grid power usage and hourly grid power cost information derived from the simulation results, the operation support device can calculate the grid power purchase cost for each combination over a preset period (e.g., one month).

[0105]

[0106]

[0107] *In an embodiment, the operation support device can derive an operation schedule (charge / discharge amount per unit time) of a battery that minimizes the purchase cost of grid power based on past history information about the load and power generation device, and calculate the purchase cost of grid power using the derived operation schedule.

[0108] Specifically, the operation support device can collect information on power production status and power consumption status over a certain period of time (e.g., over the past year). Thereafter, the operation support device can derive an operation schedule for a certain period of time (e.g., one day) that minimizes the purchase cost of system power, using an objective function defined as the purchase cost of system power.

[0109] The operation control unit can derive an operation schedule using an objective function defined based on Mixed-integer Linear Programming (MILP). Below, a detailed implementation example of this operation schedule generation method is described.

[0110] The operation control device can derive an operation schedule including the battery charge / discharge amount for each time interval using an objective function defined by the purchase cost of system power. Here, the objective function can be defined as in Mathematical Expression 1 below.

[0111]

[0112] (Here, Pgrid(t) is the grid power schedule and λgrid(t) is the grid power cost.)

[0113]

[0114] Mathematical expression 1 is an objective function for deriving the amount of charge or discharge of a battery for each time interval that can minimize the cost of purchasing power from the system. Here, the objective function according to Mathematical expression 1 may define constraints that include at least one of the following: a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the power conversion device, and a fifth condition regarding the binarization of the charge state and the discharge state.

[0115]

[0116]

[0117] (Here, PBatch(t) is the battery's charging power, PBatdch(t) is the battery's discharging power, Ppv(t) is the power generation, and Pload(t) is the power consumption.)

[0118]

[0119]

[0120] (Here, SOC(t) is the SOC of the battery, Ecap is the capacity of the battery, ηch is the charging efficiency of the power conversion device, ηdch is the discharging efficiency of the power conversion device, and tstep is the time interval.)

[0121]

[0122]

[0123] (Here, SOCmin is the lower limit of SOC, and SOCmax is the upper limit of SOC)

[0124]

[0125]

[0126] (Here, μch is the battery state for charging with a value of 0 or 1, and Pinv_max is the maximum output of the inverter)

[0127]

[0128]

[0129] (Here, μdch is the battery state for discharging, which has a value of 0 or 1)

[0130]

[0131]

[0132] The first condition can be implemented using Equation 2, which functions to determine the decision variables PBatch(t) and PBatdch(t) to balance power supply and demand. Meanwhile, in Equation 2, Ppv(t) and Pload(t) can be applied to the power production and power consumption per unit of time based on past historical information.

[0133] Meanwhile, if the collected past history information includes power consumption status information for each of multiple loads, mathematical expression 2 can be modified as shown in mathematical expression 8 below.

[0134]

[0135] (Here, Pflexible load(t) is the power consumption of a load that can be turned on and off, Pnon flexible load(t) is the power consumption of a load that cannot be turned on and off, and PEV(T) is the power consumption of the EV charging station.)

[0136] That is, the mathematical formula for the first condition regarding the balance of power supply and power consumption may have some terms added or deleted in response to the power consumption status information included in the past history information.

[0137] The second condition can be implemented by mathematical expression 3, and functions to determine the SOC in the next time interval based on the battery capacity and charge / discharge efficiency.

[0138] The third condition can be implemented by mathematical expression 4, and functions to determine the SOC within a set critical range.

[0139] The fourth and fifth conditions can be implemented by mathematical expressions 5 to 7, and function to prevent the decision variables PBatch(t) and PBatdch(t) from exceeding the output capacity of the inverter, and at the same time, prevent the charging power amount and the discharging power amount from being determined simultaneously.

[0140] The operation control device can derive PBatch(t) and PBatdch(t) that satisfy the above objective function and constraints and generate an operation schedule including the same.

[0141] The operation support device can conduct simulations using historical power consumption and power production information and generated operation schedules for energy storage systems equipped with batteries and inverters according to each combination (C #1 to #15). Thereafter, based on the hourly system power usage and hourly system power cost information derived from the simulation results, the operation support device can calculate the system power purchase cost for each combination for a preset period (e.g., one month).

[0142] Once the optimal combination representing the minimum operating cost is determined in S340, the operation support device can generate recommended combination information containing 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 implemented as [4 batteries, serial connection, Inv 9801].

[0143] 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 through a predefined GUI.

[0144] In an embodiment, the operation support device may provide an optimal operation schedule corresponding to an optimal combination to a user terminal, an EMS, or an inverter. Here, the optimal operation schedule may correspond to an operation schedule derived according to an objective function and constraints when calculating the grid power purchase cost of the optimal combination. In other words, when an optimal battery-inverter combination is applied to an energy storage system in the future, the operation support device may provide an optimal operation schedule corresponding to the recommended combination as a reference operation schedule so that the grid power purchase cost is minimized when the energy storage system is operated with the optimal battery-inverter combination.

[0145]

[0146] Figure 7 is a block diagram of an operation support device of an energy storage system according to an embodiment of the present invention.

[0147] The operation support device (500) according to an embodiment of the present invention may be incorporated into an energy storage system or provided separately outside the energy storage system. For example, the operation support device (500) may be implemented by being incorporated into a Home Energy Management System (HEMS), which is the top-level control system of a residential ESS, or may be implemented by being incorporated into a server of an ESS management company.

[0148] The operation support device (500) may include at least one processor (510), a memory (520) that stores at least one command executed through the processor, and a transmission / reception device (530) that is connected to a network and performs communication.

[0149] The at least one command may include: a command for collecting information about batteries and inverters applicable to the energy storage system; a command for deriving a plurality of combinations, each combination comprising one or more batteries and inverters, based on a structure of the energy storage system; a command for calculating an operating cost of the energy storage system for each of the combinations; and a command for generating recommended combination information including information about a combination exhibiting the lowest operating cost among the combinations.

[0150] The command for collecting information about the battery and inverter may include a command for collecting one or more of the model name, capacity, critical SOC range, and purchase cost for each battery, and the model name, limit output, and purchase cost for each inverter.

[0151] The command for deriving the plurality of combinations may include a command for deriving a range of the number of batteries based on the capacity of the batteries and the limit output of the inverter; and a command for deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and the design structure of the battery system.

[0152] The command for calculating the operating cost of the energy storage system may include a command for calculating the grid power purchase cost and the battery and inverter purchase cost for each of the combinations; and a command for calculating the operating cost based on the grid power purchase cost and the battery and inverter purchase cost.

[0153] The command for calculating the operating cost of the energy storage system may include a command for calculating a system power purchase cost for a preset period for each of the combinations based on past history information about at least one of the energy storage system, a load linked to the energy storage system, and a power generation device linked to the energy storage system.

[0154] The command for calculating the system power purchase cost may include: a command for collecting information on the power consumption status of the load and information on the power production status of the power generation device; a command for deriving an operation schedule including a charge / discharge amount for each time interval that minimizes the system power purchase cost by using an objective function defined as the system power purchase cost; and a command for calculating the system power purchase cost for a preset period for each of the combinations by applying the operation schedule and system power cost information to an energy storage system according to each of the combinations.

[0155] Here, the objective function may be defined as a constraint including at least one of a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the inverter, and a fifth condition regarding the binarization of the charge state and the discharge state.

[0156] The at least one command may further include a command for providing the generated recommended combination information to a user terminal linked to the energy storage system.

[0157] Here, the recommended combination information may include one or more of the number of batteries applied to the energy storage system, the connection structure of the batteries, and the model name of the inverter.

[0158] The operation support device (500) may also include an input interface device (540), an output interface device (550), a storage device (560), etc. Each component included in the operation support device (500) may be connected by a bus (570) and communicate with each other.

[0159] Here, the processor (510) may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. The memory (or storage device) may be comprised of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory may be comprised of at least one of a read-only memory (ROM) and a random access memory (RAM).

[0160] The operations of the method according to an embodiment of the present invention can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores data readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0161] While some aspects of the present invention have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most significant method steps may be performed by such a device.

[0162] Although the present invention has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below.

Claims

1. As an operation support device for an energy storage system, at least one processor; and A memory that stores at least one instruction to be executed through at least one processor, At least one of the above commands, A command to collect information about batteries and inverters applicable to the above energy storage system; A command for deriving a plurality of combinations, each of which is composed of one or more batteries and an inverter, based on the structure of the above energy storage system; A command for calculating the operating cost of the energy storage system for each of the above combinations; and An operation support device comprising a command to generate recommended combination information including information about a combination representing the minimum operating cost among the above combinations.

2. In claim 1, The command to collect information about the above batteries and inverters is: An operational support device comprising a command to collect, for each battery, one or more of the model name, capacity, critical SOC range, and purchase cost, and for each inverter, one or more of the model name, limit output, and purchase cost.

3. In claim 1, The command to derive the above multiple combinations is: A command to derive a range of battery numbers based on the capacity of the batteries and the limit output of the inverter; and An operation support device including a command for deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and the design structure of the battery system.

4. In claim 1, A command for calculating the operating cost of the above energy storage system is: A command for calculating the cost of purchasing grid power and the cost of purchasing batteries and inverters for each of the above combinations; and An operation support device including a command for calculating the operating cost based on the above system power purchase cost and the battery and inverter purchase cost.

5. In claim 4, A command for calculating the operating cost of the above energy storage system is: An operation support device comprising a command for calculating a system power purchase cost for a preset period of time for each of the combinations based on past history information about at least one of the energy storage system, a load linked to the energy storage system, and a power generation device linked to the energy storage system.

6. In claim 5, The command to calculate the above system power purchase cost is: A command to collect information on the power consumption status of the above load and information on the power production status of the above power production device; A command for deriving an operation schedule including the charging and discharging amount by time interval that minimizes the purchase cost of system power by using an objective function defined as the purchase cost of system power; and An operation support device including a command for calculating a system power purchase cost for a preset period for each of the combinations by applying the operation schedule and system power cost information to the energy storage system according to each of the combinations.

7. In claim 6, The above objective function is, An operation support device in which constraints are defined, including at least one of a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the inverter, and a fifth condition regarding the binarization of the charge state and the discharge state.

8. In claim 1, An operation support device further comprising a command for providing the generated recommended combination information to a user terminal linked to the energy storage system.

9. In claim 8, The above recommended combination information is: An operation support device including at least one of the number of batteries applied to the energy storage system, the connection structure of the batteries, and the model name of the inverter.

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

11. In claim 10, The steps for collecting information about the above batteries and inverters are: An operation support method comprising the step of collecting, for each battery, at least one of a model name, a capacity, a critical SOC range, and a purchase cost, and for each inverter, at least one of a model name, a limit output, and a purchase cost.

12. In claim 10, The step of deriving the above multiple combinations is: A step of deriving a range of the number of batteries based on the capacity of the battery and the limit output of the inverter; and An operation support method comprising a step of deriving a plurality of combinations applicable to the energy storage system based on the range of the number of batteries and the design structure of the battery system.

13. In claim 10, The step of calculating the operating cost of the above energy storage system is: A step of calculating the system power purchase cost and the battery and inverter purchase cost for each of the above combinations; and An operation support method comprising a step of calculating the operating cost based on the system power purchase cost and the battery and inverter purchase cost.

14. In claim 13, The step of calculating the operating cost of the above energy storage system is: An operation support method comprising a step of calculating a system power purchase cost for a preset period of time for each of the combinations based on past history information about at least one of the energy storage system, a load linked to the energy storage system, and a power generation device linked to the energy storage system.

15. In claim 14, The step of calculating the above system power purchase cost is: A step of collecting information on the power consumption status of the load and information on the power production status of the power production device; A step of deriving an operation schedule including the charging and discharging amount by time interval that minimizes the purchase cost of system power by using an objective function defined as the purchase cost of system power; and An operation support method comprising a step of calculating a system power purchase cost for a preset period for each of the combinations by applying the operation schedule and system power cost information to the energy storage system according to each of the combinations.

16. In claim 15, The above objective function is, An operation support method, wherein constraints are defined, including at least one of a first condition regarding the balance of power supply and power consumption, a second condition regarding the state of charge (SOC) according to the charge / discharge efficiency of the battery, a third condition regarding the limit charge amount of the battery, a fourth condition regarding the limit output of the inverter, and a fifth condition regarding the binarization of the charge state and the discharge state.

17. In claim 10, An operation support method further comprising a command for providing the generated recommended combination information to a user terminal linked to the energy storage system.

18. In claim 17, The above recommended combination information is: An operation support method comprising at least one of the number of batteries applied to the energy storage system, the connection structure of the batteries, and the model name of the inverter.

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