Energy management device and energy management method

Abstract

An energy management device according to embodiments of the present invention intercommunicates with an electrical power grid, an electrical power generating device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger. The energy management device includes: at least one processor; and a memory storing at least one instruction executed via the at least one processor. Here, the at least one instruction may include: an instruction for collecting basic information, the basic information including information on a power generation state and a power consumption state, and grid power cost information; instructions for establishing an ESS operation schedule and an EV operation schedule by using the collected basic information, the ESS operation schedule for controlling charging and discharging operations of the ESS battery, and the EV operation schedule for controlling charging and discharging operations of the EV battery; and instructions for controlling the ESS battery and the EV battery to be charged / discharged in accordance with the ESS operation schedule and the EV operation schedule.

Description

Technical Field

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0101159 filed in the Korean Intellectual Property Office on August 2, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to an energy management device and an energy management method, and more particularly to an energy management device that communicates with a power grid, a power generation device, an energy storage system, and a bidirectional electric vehicle charger, and an energy management method performed by the energy management device. Background Art

[0003] Energy storage systems (ESS) use batteries that store energy in a form that is operated while interoperating with new and renewable energy sources and the power grid. In recent years, as smart grids and new and renewable energy sources have become more popular and the efficiency and stability of the power grid have gained attention, energy storage systems are increasingly needed to control power supply and demand and improve power quality. Depending on the purpose of use, energy storage systems can vary in power output and capacity, and multiple battery systems can be interconnected to form a large-capacity energy storage system.

[0004] Recently, an ESS linked with a photovoltaic (PV) system and an electric vehicle (EV) charging system has been proposed. In this article, a higher-level control device of the PV and EV linked ESS is configured to appropriately distribute grid power supplied from the grid, power generated by the PV system, and stored power from the ESS to supply the distributed power to the load and the EV charger, and to store the remaining power in the battery system.

[0005] PV and EV linked ESS is operated by considering various factors including the amount of power generated by the PV system, the amount of power required by the load and EV charger, and the state of charge of the battery. However, the most important goal considered by the user of ESS is minimization of power purchase cost, but the conventional ESS operation method aims to maximize the amount of PV power generated, maximize battery performance, or minimize the amount of power used by the grid.

[0006] Therefore, there is a need for an appropriate energy management technology that enables optimal operation while minimizing electricity purchase costs taking into account the amount of PV power generated, the amount of power demanded by loads and EV chargers, and the state of charge of the battery. Summary of the invention

[0007] Technical issues

[0008] An object of the present invention is to provide an energy management device capable of minimizing the cost of purchasing grid electricity.

[0009] Another object of the present invention is to provide an energy management method performed by the energy management device.

[0010] Technical Solution

[0011] An exemplary embodiment of the present invention provides an energy management device that communicates with an electric power grid, an electric power generation device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, the energy management device comprising: at least one processor; and a memory storing at least one instruction executed via the at least one processor.

[0012] Herein, at least one instruction may include: an instruction for collecting basic information, the basic information including information on a power generation state and a power consumption state, and grid power cost information; an instruction for establishing an ESS operation schedule and an EV operation schedule by using the collected basic information, the ESS operation schedule being used to control charging and discharging operations of an ESS battery, and the EV operation schedule being used to control charging and discharging operations of an EV battery; and an instruction for controlling the ESS battery and the EV battery to be charged / discharged according to the ESS operation schedule and the EV operation schedule.

[0013] The instructions for establishing the operation schedule may include instructions for deriving the charging and discharging amounts of the ESS battery for each time interval and the charging and discharging amounts of the EV battery for each time interval that minimize the cost of purchasing grid power.

[0014] The instructions for establishing the ESS operation schedule and the EV operation schedule may include instructions for deriving a charge and discharge amount of the ESS battery per time interval and a charge and discharge amount of the EV battery per time interval by using an objective function defined by a cost of purchasing grid power.

[0015] The objective function may include defined constraints, the defined constraints including at least one of the following: a first condition regarding a balance between power supply and power consumption, a second condition regarding a state of charge (SOC) based on a charge / discharge efficiency of an ESS battery, a third condition regarding a limit charge amount of the ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of the charge / discharge state of the ESS battery. In this article, the constraints may also include at least one of the following: a sixth condition regarding the SOC according to the charge / discharge efficiency of an EV battery, a seventh condition regarding a limit charge amount of an EV battery, an eighth condition regarding a limit output of a bidirectional EV charger, and a ninth condition regarding binarization of the charge / discharge state of the bidirectional EV charger.

[0016] The instructions for collecting basic information may include instructions for collecting basic information including information about a power generation state and a power consumption state for a predefined first period. In the present invention, the instructions for establishing an ESS operation schedule and an EV operation schedule may include instructions for generating power generation prediction information and power consumption prediction information for a second period by using the collected basic information, the second period being predefined as a period after the first period; and instructions for generating the ESS operation schedule and the EV operation schedule for the second period based on the generated prediction information.

[0017] The instructions for collecting basic information may include instructions for receiving load schedule information for turning on and off a controllable load from a user terminal, in which a time interval for operating the load in an on state or an off state is set. Herein, the instructions for establishing an ESS operation schedule and an EV operation schedule may include instructions for generating an ESS operation schedule and an EV operation schedule based on the load schedule information.

[0018] The instructions for collecting basic information may include instructions for receiving EV schedule information from a user terminal, in which a time interval during which the EV is connected to the bidirectional EV charger is set. Herein, the instructions for establishing an ESS operation schedule and an EV operation schedule may include instructions for generating an ESS operation schedule and an EV operation schedule based on the EV schedule information.

[0019] The instructions for controlling the ESS battery and the EV battery to be charged / discharged may include instructions for providing an ESS operation schedule to a power conversion device that communicates with the ESS battery and providing an EV operation schedule to a bidirectional EV charger so that the ESS battery is charged and discharged according to the ESS operation schedule and the EV battery is charged and discharged according to the EV operation schedule.

[0020] Another exemplary embodiment of the present invention provides an energy management method performed by an energy management device that communicates with an electric power grid, an electric power generation device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, the energy management method comprising: collecting basic information, the basic information including information on a power generation state and a power consumption state, and grid power cost information; establishing an ESS operation schedule and an EV operation schedule by using the collected basic information, the ESS operation schedule being used to control charging and discharging operations of an ESS battery, and the EV operation schedule being used to control charging and discharging operations of an EV battery; and controlling the ESS battery and the EV battery to be charged / discharged according to the ESS operation schedule and the EV operation schedule.

[0021] Establishing the operating schedule may include deriving a charge and discharge amount of the ESS battery for each time interval and a charge and discharge amount of the EV battery for each time interval that minimizes the cost of purchasing grid power.

[0022] Establishing the ESS operation schedule and the EV operation schedule may include deriving a charge and discharge amount of the ESS battery per time interval and a charge and discharge amount of the EV battery per time interval by using an objective function defined by a cost of purchasing grid power.

[0023] The objective function may include defined constraints, the defined constraints including at least one of the following: a first condition regarding a balance between power supply and power consumption, a second condition regarding a state of charge (SOC) based on a charge / discharge efficiency of an ESS battery, a third condition regarding a limit charge amount of the ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of the charge / discharge state of the ESS battery. In this article, the constraints may also include at least one of the following: a sixth condition regarding the SOC according to the charge / discharge efficiency of an EV battery, a seventh condition regarding a limit charge amount of an EV battery, an eighth condition regarding a limit output of a bidirectional EV charger, and a ninth condition regarding binarization of the charge / discharge state of the bidirectional EV charger.

[0024] Collecting basic information may include: collecting basic information including information about a power generation state and a power consumption state for a predefined first period. In this article, establishing an ESS operation schedule and an EV operation schedule may include: generating power generation prediction information and power consumption prediction information for a second period by using the collected basic information, the second period being predefined as a period after the first period; and generating an ESS operation schedule and an EV operation schedule for the second period based on the generated prediction information.

[0025] Collecting basic information may include: receiving load schedule information for turning on and off the controllable load from the user terminal, in which a time interval for operating the load in an on state or an off state is set. In this article, establishing the ESS operation schedule and the EV operation schedule may include generating the ESS operation schedule and the EV operation schedule based on the load schedule information.

[0026] Collecting basic information may include: receiving EV schedule information from a user terminal, in which a time interval during which the EV is connected to the bidirectional EV charger is set. In this article, establishing the ESS operation schedule and the EV operation schedule may include generating the ESS operation schedule and the EV operation schedule based on the EV schedule information.

[0027] Controlling the ESS battery and the EV battery to be charged / discharged may include: providing an ESS operation schedule to a power conversion device that communicates with the ESS battery, and providing an EV operation schedule to a bidirectional EV charger, so that the ESS battery is charged and discharged according to the ESS operation schedule and the EV battery is charged and discharged according to the EV operation schedule.

[0028] Beneficial Effects

[0029] According to an exemplary embodiment of the present invention, the operation cost of the ESS connected to PV and EV can be minimized by deriving the operation schedule of the ESS and EV charger that can minimize the grid power purchase cost, and controlling the ESS and EV charger according to the derived operation schedule. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a block diagram illustrating an energy storage system to which the present invention is applicable.

[0031] Figure 2 is a diagram illustrating an example embodiment of an energy storage system to which the present invention is applicable.

[0032] Figure 3 is a flow chart of an energy management method according to an exemplary embodiment of the present invention.

[0033] Figure 4 is a flowchart of an operation schedule establishing method according to an exemplary embodiment of the present invention.

[0034] Figure 5 is a diagram illustrating an example screen of a user terminal for explaining EV schedule information according to an exemplary embodiment of the present invention.

[0035] Figure 6 is a diagram illustrating an example screen of a user terminal for explaining load schedule information according to an exemplary embodiment of the present invention.

[0036] Figure 7 is a block diagram illustrating an energy management apparatus according to an exemplary embodiment of the present invention.

[0037] 100: Power grid

[0038] 200: Load

[0039] 300: Power generation equipment

[0040] 400: EV charger

[0041] 500: Energy Storage System

[0042] 600: Energy management equipment

[0043] 700: User terminal DETAILED DESCRIPTION

[0044] The present invention may have various modifications and exemplary embodiments, and therefore specific exemplary embodiments will be illustrated and described in the drawings. However, it is not intended to limit the present invention to specific exemplary embodiments, and it will be appreciated that the present invention includes all modifications, equivalents or substitutions included in the spirit and technical scope of the present invention. Throughout the description of each of the drawings, similar reference numerals are used for similar components.

[0045] Terms such as first, second, A, B are used to describe various constituent elements, but constituent elements are not limited by terms. Terms are only used to distinguish one constituent element from another constituent element. For example, without departing from the scope of the present invention, the first constituent element can be named as the second constituent element, and similarly, the second constituent element can be named as the first constituent element. The term "and / or" includes a combination of multiple related description items, or any one of multiple related description items.

[0046] It should be understood that when a constituent element is mentioned as being "coupled to" or "connected to" another constituent element, the constituent element may be directly coupled to or connected to the other constituent element, but there may also be intermediate elements. Conversely, when a constituent element is "directly coupled to" or "directly connected to" another constituent element, it should be understood that there are no intermediate elements.

[0047] The terms used in this application are only used to describe specific exemplary embodiments and are not intended to limit the present invention. Singular expressions used herein include plural expressions unless they have clear opposite meanings in the context. In this application, it will be recognized that the terms "including" and "having" are intended to specify the existence of the characteristics, numbers, steps, operations, constituent elements and parts or combinations thereof described in the specification, and do not exclude the possibility of pre-existing or adding one or more other characteristics, numbers, steps, operations, constituent elements and parts or combinations thereof.

[0048] All terms used in this document, including technical or scientific terms, have the same meanings as those generally understood by those skilled in the art unless they are defined differently. Terms defined in general dictionaries should be interpreted as having meanings that match their meanings in the context of the relevant field, and should not be interpreted as idealized or overly formalized meanings unless they are clearly defined in this application.

[0049] Some of the terms used in this specification are defined below.

[0050] The state of charge (SOC) is the current state of charge of the battery expressed in percentage (%), and the state of health (SOH) is the current state of degradation of the battery expressed in percentage (%).

[0051] The power limit indicates the limit of the power that can be output, which is preset by the battery manufacturer based on the state of the battery or set according to the SOC. Depending on whether the battery is being charged or discharged, the power limit can be divided into a charging power limit and a discharging power limit.

[0052] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

[0053] Figure 1 is a block diagram illustrating an energy storage system to which the present invention is applicable.

[0054] The energy management device 600 may be linked with the grid 100 , the load 200 , the power generation device 300 , the electric vehicle (EV) charger 400 , and the energy storage system 500 .

[0055] The energy storage system 500 may be electrically connected to the grid 100 and the power generating device 300 , and may receive power from the grid 100 and the power generating device 300 and internally store the received power.

[0056] The energy storage system 500 may be electrically connected to the load 200 and the EV charger 400 to supply power stored in a battery (hereinafter, ESS battery) configured in the energy storage system to the load 200 and the EV charger 400. Meanwhile, the load 200 may be electrically connected to the grid 100 and the power generation device 300 to receive power from the grid 100 and the power generation device 300.

[0057] The power generation device 300 is a device for generating power by using a power generation device, and may include at least one of photovoltaic, solar thermal, wind, and geothermal power generation devices. However, the type of power generation device 300 is not an essential component of the present invention, so that the scope of the present invention is not limited to these entities.

[0058] EV charger 400 may be electrically connected to grid 100 , power generation device 300 , and energy storage system 500 , and may receive power from grid 100 , power generation device 300 , and energy storage system 500 .

[0059] In an exemplary embodiment, the EV charger 400 may correspond to a bidirectional EV charger. In this case, the EV charger 400 may charge a battery (hereinafter, EV battery) included in the EV by using power supplied from an external source, and may discharge the power stored in the EV battery to the external source. In other words, in a state where the EV is connected to the EV charger 400, the functions of the bidirectional EV charger and the EV battery may be the same as those of the energy storage system 500 according to the present invention.

[0060] When EV charger 400 is configured as a bidirectional charger, EV charger 400 may supply internally stored power to load 200 and energy storage system 500 .

[0061] The energy management device 600 may be configured to be networked with at least one of the load 200, the power generation device 300, the EV charger 400, and the energy storage system 500 to transmit and receive data to each other. The energy management device 600 may be included and configured inside the energy storage system 500, or may be separated and outside the energy storage system 500. For example, the energy management device 600 may be implemented while being included in a home energy management system (HEMS), which is a top-level control system of a residential ESS, or may be implemented while being included in a server of an ESS management company and connected to the HEMS via a network.

[0062] The energy management device 600 may collect at least one of the operating state of the energy storage system 500, the power generation state of the power generation device 300, and the power consumption state of the load 200, and may establish an operation schedule for optimal operation of the energy storage system 500 and the EV charger 400 by using the collected information. Herein, the energy management device 600 may establish an ESS operation schedule for controlling the energy storage system 500 and an EV operation schedule for controlling the EV charger 400 by using a predefined operation schedule generation algorithm.

[0063] The operation schedule may include the charge and discharge amount (or reference power amount) for each time interval. Specifically, the ESS operation schedule may include the charge / discharge amount of the ESS battery for each time interval, and the EV operation schedule may include the charge / discharge amount of the EV battery for each time interval.

[0064] The energy management device 600 may transmit the established ESS operation schedule to the battery charge and discharge control device of the energy storage system 500 so that the ESS battery is charge and discharge controlled according to the ESS operation schedule.

[0065] Furthermore, the energy management device 600 may transmit the established EV operation schedule to the EV charger 400 so that the EV battery is charge and discharge controlled according to the EV operation schedule.

[0066] Figure 2 is a diagram illustrating an example embodiment of an energy storage system to which the present invention is applicable.

[0067] refer to Figure 2 , the energy storage system 500 may include an ESS battery 510 storing power, and an inverter 520 controlling charging and discharging operations of the ESS battery 510 .

[0068] The ESS battery 510 may be generally implemented in the form of a plurality of battery packs constituting a battery rack and a plurality of battery racks constituting a battery bank. Herein, a battery pack may also be referred to as a battery module, depending on the device or system in which the battery is used.

[0069] Each battery may be equipped with a battery management system (BMS). The BMS may be used to monitor the current, voltage, and temperature of each battery rack (or group) under its control, calculate the state of charge (SOC) based on the monitoring results, and control charging and discharging.

[0070] The inverter 520 is also referred to as a power conditioning system (PCS) or a power conversion system (PCS), and may control power supplied from the outside to the battery and power supplied from the battery to the outside.

[0071] The inverter 520 may include a power management system (PMS), and the energy management device 600 may be configured to intercommunicate with the power management system of the inverter 520 to mutually transmit and receive data.

[0072] The load 200 may include a plurality of loads 200-1 to 200-N. Herein, at least some of the loads 200-1 to 200-N may be configured as first loads that are not controllably turned on and off, and the remaining loads may be configured as second loads that are controllably turned on and off.

[0073] The first load may be a load that cannot be turned off, or a load that may have supplied power that cannot be cut off by the control of the energy management device. Alternatively, the second load may mean a load that can be powered off, or a load that may have supplied power that may be cut off by the control of the energy management device. In this article, the second load may be defined based on a selection signal input by a user.

[0074] The PV system may include PV modules 310 (eg, solar panels), a PV inverter 320 (which is an AC / DC inverter), and may be configured to connect AC terminals of the PV inverter 320 with AC terminals of an inverter 520 of an energy storage system in an AC link.

[0075] The EV charger may correspond to the bidirectional EV charger 420. Herein, the bidirectional EV charger 420 may be configured to include an AC / DC inverter, and may have an AC terminal connected to an AC link.

[0076] The bidirectional EV charger 420 may control charging and discharging operations of an EV battery included in the EV 410 .

[0077] The energy management device 600 serves as a higher-level control device for the power grid, multiple loads, the PV system, the bidirectional EV charger, and the energy storage system, and can be configured to collect status information of each of the configurations and control the operation of one or more of the loads, the PV system, the bidirectional EV charger, and the energy storage system based on the collected status information.

[0078] The energy management device 600 can establish an operation schedule based on one or more of the charge and discharge amount of the ESS battery, the charge and discharge amount of the EV battery, the amount of power generated by the PV, and the power consumption amount of the load to minimize the grid power purchase cost. Herein, the energy management device 600 can establish an ESS operation schedule for controlling the energy storage system 500 and an EV operation schedule for controlling the EV charger 400 by using a predefined objective function and constraints.

[0079] The energy management device 600 may be configured to be connected to the user terminal 700 via a network to transmit and receive data to and from each other.

[0080] The user terminal 700 may refer to a computing device used by an owner or an administrator of the energy storage system, such as a personal computer (PC), a mobile phone, a tablet PC, and the like.

[0081] The energy management device 600 may receive load schedule information of the second load from the user terminal 700. Herein, the load schedule information may include information on a time interval at which each of the second loads operates in an on state or an off state as set by a user.

[0082] The energy management device 600 may control the on-off of the second load based on the load schedule information received from the user terminal 700. For example, when the load schedule information including [load 4, off at 14:00, on at 16:00] is received, the energy management device 600 may turn off the load 4 at 14:00 or otherwise shut down the power supply to the load 4. Subsequently, the energy management device 600 may turn on the load 4 at 16:00 or cancel the blocking of the power supply to the load 4.

[0083] The energy management device 600 may receive EV schedule information of the EV 410 from the user terminal 700. Herein, the EV schedule information may include information about a time interval set by a user during which the EV is connected to the bidirectional EV charger. For example, the energy management device 600 may receive EV schedule information including [EV access time, 17:00 to 19:00, 21:00 to 24:00] from the user terminal 700.

[0084] The load schedule information and the EV schedule information received from the user terminal 700 may be utilized as basic information in the process of establishing the ESS operation schedule and the EV operation schedule.

[0085] The energy management device 600 may transmit the established ESS operation schedule to the inverter 520 of the energy storage system 500, and the inverter 520 may control the charging and discharging operations of the ESS battery 510 according to the ESS operation schedule. For example, the inverter 520 may receive the ESS operation schedule of a specific date from the energy management device 600, and control the charging and discharging operations of the ESS battery 510 based on the reference power of each time interval included in the ESS operation schedule.

[0086] Energy management device 600 may transmit the established EV operation schedule to bidirectional EV charger 420, and bidirectional EV charger 420 may control the charging and discharging operations of the EV battery according to the EV operation schedule. For example, bidirectional EV charger 420 may receive the EV operation schedule of a specific date from energy management device 600, and may control the charging and discharging operations of the EV battery based on the reference power of each time interval included in the EV operation schedule.

[0087] Figure 2 The energy storage system illustrated in FIG is an AC-coupled ESS, in which the PV system, the bidirectional EV charger, the load, and the energy storage system are connected in an AC link. However, the present invention is also applicable to a DC-coupled energy storage system, in which the output terminal of the PV system, the input terminal of the EV charger, and the output terminal of the energy storage system are connected in a DC link, and the DC link is connected to one terminal of an AC / DC inverter.

[0088] Figure 3 is a flow chart of an energy management method according to an exemplary embodiment of the present invention.

[0089] The energy management method according to an exemplary embodiment of the present invention may be performed by an energy management device that intercommunicates with a power grid, a power generation device, an energy storage system, and a bidirectional EV charger.

[0090] The energy management device may collect basic information for establishing an operation schedule (S310). Herein, the basic information may include information on a power generation state and a power consumption state, and grid power cost information.

[0091] Using the collected basic information, the energy management device may establish an ESS operation schedule for controlling the charging and discharging operations of the ESS battery and an EV operation schedule for controlling the charging and discharging operations of the EV battery (S320). Herein, the ESS operation schedule may include the charging / discharging amount (or reference power amount) of the ESS battery per time interval, and the EV operation schedule may include the charging / discharging amount (or reference power amount) of the EV battery per time interval.

[0092] In the operation schedule, the time interval may be defined in various ways as needed, such as in units of 30 minutes, in units of 15 minutes, or in units of 1 minute. The operation schedule may include information on the duration of the operation, for example, the start time of the operation may be defined as 00:00 of a specific date, and the end time of the operation may be defined as 24:00 of the corresponding date. The energy management device may derive an ESS operation schedule and an EV operation schedule that minimize the cost of purchasing grid power by utilizing an optimization technique using an objective function.

[0093] The energy management device may control the ESS battery and the EV battery to be charged and discharged according to the operation schedule established in operation S320 ( S330 ).

[0094] Specifically, the energy management device may send the ESS operation schedule to the inverter of the energy storage system, and the inverter may control the charging and discharging operation of the ESS battery based on the charging and discharging amount of each time interval included in the ESS operation schedule. In addition, the energy management device may send the EV operation schedule to the bidirectional EV charger, and the bidirectional EV charger may control the charging and discharging operation of the EV battery based on the charging and discharging amount of each time interval included in the EV operation schedule.

[0095] In an exemplary embodiment, the energy management device may adjust the operation schedule during the process in which the ESS battery and the EV battery operate according to the operation schedule. Herein, the energy management device may adjust the operation schedule based on a difference between a predicted value utilized in the process of establishing the operation schedule and an actual value collected during the operation process according to the operation schedule.

[0096] Figure 4 is a flow chart of an operation schedule establishment method according to an exemplary embodiment of the present invention. Figure 4 Detailed Description Figure 3 Specific exemplary embodiments of steps S310 to S320.

[0097] The energy management device collects basic information ( S410 ).

[0098] The basic information may include ESS battery related parameters, EV battery related parameters, grid power cost information, and information on power generation status and power consumption status for a predefined first period. Herein, the basic information may also include load schedule information, EV schedule information.

[0099] For an ESS battery, the ESS battery related parameters may include one or more of capacity, an upper limit value of SOC, a lower limit value of SOC, a charge / discharge efficiency of the power conversion device, and a power limit of the power conversion device.

[0100] For EV batteries, EV battery-related parameters may include one or more of capacity, charging / discharging efficiency, an upper limit value of SOC, a lower limit value of SOC, a charging / discharging efficiency of a bidirectional EV charger, and a power limit of a bidirectional EV charger. In this article, the energy management device may receive information about one or more of an upper limit value of SOC and a lower limit value of SOC from a user terminal. For example, the user terminal may receive an input of a minimum guaranteed SOC of an EV battery from a user and send the input minimum guaranteed SOC to the energy management device. In this case, the energy management device may define the minimum guaranteed SOC received from the user terminal as the lower limit value of the SOC of the EV battery.

[0101] The grid power cost information may include grid power cost per time interval.

[0102] The information about the power generation state and the power consumption state may include the power generation amount of the power generation device per time interval and the power consumption amount of the corresponding load per time interval.

[0103] Considering the accuracy of prediction of the prediction information, the first period may be defined as various ranges, for example, from one year before a specific date (nth day) to one day (n-1th day) before the corresponding date (nth day).

[0104] The energy management apparatus may generate prediction information for a second period, which is predefined as a period after the first period, by using the collected basic information ( S420 ).

[0105] The prediction information may include power generation prediction information and power consumption prediction information. Herein, the power generation prediction information may include the predicted power generation of the power generation device per time interval, and the power consumption prediction information may include the predicted power consumption of the load per time interval.

[0106] The second period may be defined as an operation period of the operation schedule, for example, from 00:00 to 24:00 on a specific date (nth day).

[0107] In an exemplary embodiment, the energy management device may derive pattern information including a power generation pattern and a power consumption pattern based on information about a power generation state and a power consumption state included in the basic information, and generate power generation prediction information and power consumption prediction information by using the derived pattern information. For example, the energy management device may calculate the average value of power generation and power consumption for each time interval within a one-year period to derive a predicted power generation and predicted power consumption for each time interval of a specific date.

[0108] In another exemplary embodiment, the energy management device may generate power generation prediction information and power consumption prediction information by using a prediction model based on artificial intelligence. For example, the prediction model may be configured to be pre-trained using training data on power generation status and power consumption status, and when basic information is input as input data, output power generation prediction information and power consumption prediction information (e.g., predicted power generation amount and predicted power consumption amount for each time interval on a specific date) as output data.

[0109] The energy management device may generate an ESS operation schedule and an EV operation schedule for the second period based on the generated prediction information (S430). In this article, the energy management device may derive the ESS operation schedule and the EV operation schedule by using an objective function defined based on mixed integer linear programming (MILP). Hereinafter, a specific implementation example of the operation schedule generation method will be described in detail.

[0110] The energy management device can derive an ESS operation schedule including the charging and discharging amount of the ESS battery per time interval and an EV operation schedule including the charging and discharging amount of the EV battery per time interval by using an objective function defined as the cost of purchasing grid power. Herein, the objective function can be defined as represented in the following formula 1.

[0111] [Formula 1]

[0112]

[0113] (in, is the grid power schedule, and is the grid electricity fee)

[0114] Formula 1 is an objective function for deriving the charging and discharging amount of the ESS battery and the charging and discharging amount of the EV battery for each time interval that minimizes the grid power purchase cost.

[0115] In this paper, the objective function according to Formula 1 may be subject to one or more constraints.

[0116] The constraint may include one or more of the following conditions: a first condition regarding a balance between power supply and power consumption, a second condition regarding a state of charge (SOC) based on a charge / discharge efficiency of an ESS battery, a third condition regarding a limit charge amount of an ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of a charge / discharge state of an ESS battery. In this document, the constraint may also include at least one of the following: a sixth condition regarding a state of charge (SOC) according to a charge / discharge efficiency of an EV battery, a seventh condition regarding a limit charge amount of an EV battery, an eighth condition regarding a limit output of a bidirectional EV charger, and a ninth condition regarding binarization of a charge / discharge state of a bidirectional EV charger.

[0117] [Formula 2]

[0118]

[0119] (in is the charging power of the ESS battery, is the discharge power of the ESS battery, It is the charging power of the EV battery. is the discharge power of the EV battery, is the predicted electricity generation, and is the predicted power consumption)

[0120] [Formula 3]

[0121]

[0122] (in, is the SOC of the ESS battery, is the capacity of the ESS battery, is the charging efficiency of the power conversion device, is the discharge efficiency of the power conversion device, and is the time interval)

[0123] [Formula 4]

[0124]

[0125] (in is the lower limit of the SOC of the ESS battery, and is the upper limit of the SOC of the ESS battery)

[0126] [Formula 5]

[0127]

[0128] (in, is a battery status value of 0 or 1 for charging, and is the maximum output of the power conversion device)

[0129] [Formula 6]

[0130]

[0131] (in, is the battery status value for discharge, which is 0 or 1)

[0132] [Formula 7]

[0133]

[0134] [Formula 8]

[0135]

[0136] (in, is the SOC of the EV battery, is the capacity of the EV battery, is the charging efficiency of the bidirectional EV charger, is the discharge efficiency of the bidirectional EV charger, and is the time interval)

[0137] [Formula 9]

[0138]

[0139] (in, is the lower limit of the SOC of the EV battery, and is the upper limit of the SOC of the EV battery)

[0140] [Formula 10]

[0141]

[0142] (in, is the EV connection status value of 0 or 1, is a charge status value that can be 0 or 1, and is the maximum output of a bidirectional EV charger)

[0143] [Formula 11]

[0144]

[0145] (in, is the discharge status value of 0 or 1)

[0146] [Formula 12]

[0147]

[0148] The first condition can be implemented as Equation 2 and is used to ensure that the decision variable , , , and is determined to balance the supply and demand of electricity.

[0149] The second condition may be implemented as Formula 3, and is used to determine the SOC of the ESS battery in the next time interval based on the capacity of the ESS battery and the charging and discharging efficiency of the power conversion device.

[0150] The third condition may be implemented as Formula 4, and is used to ensure that the SOC of the ESS battery is determined to be within a set threshold range.

[0151] The fourth and fifth conditions can be implemented as formulas 5 to 7 and are used to ensure that the decision variables and The power limit of the power conversion equipment (eg, inverter) is not exceeded, and the charging power amount and the discharging power amount cannot be determined at the same time.

[0152] The sixth condition may be implemented as Formula 8 and is used to determine the SOC of the EV battery in the next time interval based on the capacity of the EV battery and the charging / discharging efficiency of the bidirectional EV charger.

[0153] The seventh condition can be implemented as Formula 9 and is used to ensure that the SOC of the EV battery is determined to be within a set threshold range. In this article, one or more of the lower limit value of the SOC of the EV battery and the upper limit value of the SOC can be set by the user. For example, the lower limit value of the SOC of the EV battery can be defined as the minimum guaranteed SOC of the EV battery received from the user terminal. According to the operation schedule derived from the objective function reflecting the seventh condition, the EV battery can perform charging / discharging operations at or above the minimum guaranteed SOC.

[0154] The eighth and ninth conditions can be implemented as formulas 10 to 12 and are used to ensure that the decision variables and The power limit of the bidirectional EV charger is not exceeded, and the charging power amount and the discharging power amount cannot be determined simultaneously.

[0155] The EV connection state value β reflected in formulas 10 and 11 EV It may be defined as [1] in the connected state and [0] for the disconnected state. Herein, the EV connection state value may be defined based on the EV schedule information received from the user terminal.

[0156] On the other hand, when the plurality of loads include one or more second loads (loads that can be controlled to be turned on and off), Formula 2 may be modified as expressed in Formulas 13 and 14 below.

[0157] [Formula 13]

[0158]

[0159] (in, is the predicted power consumption of the first load, and is the predicted power consumption of the second load)

[0160] [Formula 14]

[0161]

[0162] (in, is the on-off state value of the load with a value of 0 or 1)

[0163] When the load includes a first load and a second load, in S420, the energy management device can generate a predicted power consumption of the first load and a predicted power consumption of the second load. In this article, the first condition on the balance of power supply and power consumption can reflect the on-off schedule of the second load, as expressed in Formula 13.

[0164] The on-off state value of the load reflected in Equation 14 It can be defined as [1] for the on state and [0] for the off state. Herein, the on-off state value of the load can be defined based on the load schedule information received from the user terminal.

[0165] The energy management device can derive the , , , and , and generate and The ESS operation schedule includes and Meanwhile, the objective function and constraints established for the operation schedule may have various modification examples, and the rights of the present invention are not limited to the above formula.

[0166] Figure 5 is a diagram illustrating an example screen of a user terminal for explaining EV schedule information according to an exemplary embodiment of the present invention.

[0167] The energy management device may receive the minimum guaranteed SOC and EV schedule information from the user terminal, and may generate the operation schedule based on the received minimum guaranteed SOC and EV schedule information.

[0168] More specifically, the user terminal may receive an input of a minimum guaranteed SOC of an EV battery and EV schedule information from a user via a predefined Graphic User Interface (GUI).

[0169] For example, Figure 5 As illustrated in , the user terminal may receive a specific SOC value (75%) as the minimum guaranteed SOC, and EV schedule information of time intervals (time 1: 00:00 to 07:00, time 2: 17:00 to 19:00, and time 3: 21:00 to 24:00) during which the EV is connected to the bidirectional EV charger from the user. Then, the user terminal may transmit the minimum guaranteed SOC and EV schedule information input by the user to the energy management device.

[0170] The energy management device may reflect the minimum guaranteed SOC received from the user terminal in the seventh condition (Formula 9) among the constraints for deriving the operation schedule. In addition, the energy management device may reflect the EV schedule information received from the user terminal in the eighth and ninth conditions (Formulas 10 and 11) among the constraints for deriving the operation schedule.

[0171] The energy management device can derive the energy management system that satisfies the objective function according to Formula 1 and the constraints (the first condition to the ninth condition) reflecting the information received from the user terminal. , , , and , and generate and The ESS operation schedule includes and EV operation schedule.

[0172] Figure 6 is a diagram illustrating an example screen of a user terminal for explaining load schedule information according to an exemplary embodiment of the present invention.

[0173] The energy management device may receive load schedule information for an on-off controllable load from a user terminal, in which a time interval for operating the load in an on state or an off state is set, and generate an operation schedule based on the received load schedule information.

[0174] More specifically, the user terminal may receive the load schedule information of the second load via a predefined GUI.

[0175] For example, Figure 6 As illustrated in , the user terminal may output a list of second loads (loads 4, 5, 6, and 7) that can be controlled to be turned on and off among a plurality of loads (loads 1 to load N). Then, the user terminal may receive information about time intervals during which each of the second loads operates in an on state or an off state from the user ([load 4, 14:00 to 16:00, on], [load 5, 15:00 to 18:00, on], [load 6, 12:00 to 13:00, on], and [load 7, 14:00 to 18:00, off]).

[0176] Then, the user terminal may transmit the load schedule information input by the user to the energy management device.

[0177] The energy management device may control the on-off state of the second load based on the load schedule information received from the user terminal. For example, the energy management device may switch load 4 from the off state to the on state at 14:00, and switch load 4 from the on state to the off state at 16:00. In addition, the energy management device may switch load 7 from the on state to the off state at 14:00, and switch load 7 from the off state to the on state at 18:00.

[0178] The energy management device may reflect the load schedule information received from the user terminal in the first condition (Formulas 13 and 14) among the constraints for deriving the operation schedule.

[0179] The energy management device can derive the energy management system that satisfies the objective function according to Formula 1 and the constraints (the first condition to the ninth condition) that reflect the information received from the user terminal. , , , and , and generate and The ESS operation schedule includes and EV operation schedule.

[0180] Figure 7 is a block diagram illustrating an energy management apparatus according to an exemplary embodiment of the present invention.

[0181] The energy management device 600 according to an exemplary embodiment of the present invention may be configured to be included in the energy storage system, or may be separated and located outside the energy storage system. For example, the energy management device 600 may be implemented to be included in a HEMS as a top-level control system of a residential ESS, or may be implemented to be included in a server of an ESS management company and configured to be connected to the HEMS via a network.

[0182] The energy management device 600 may include at least one processor 610 , a memory 620 storing at least one instruction executed via the processor, and a transceiver device 630 performing communication via a network connection.

[0183] At least one instruction may include: an instruction for collecting basic information, the basic information including information on a power generation state and a power consumption state, and grid power cost information; an instruction for establishing an ESS operation schedule and an EV operation schedule by using the collected basic information, the ESS operation schedule being used to control charging and discharging operations of an ESS battery, and the EV operation schedule being used to control charging and discharging operations of an EV battery; and an instruction for controlling the ESS battery and the EV battery to be charged / discharged according to the ESS operation schedule and the EV operation schedule.

[0184] The instructions for establishing the operation schedule may include instructions for deriving the charging and discharging amounts of the ESS battery for each time interval and the charging and discharging amounts of the EV battery for each time interval that minimize the cost of purchasing grid power.

[0185] The instructions for establishing the ESS operation schedule and the EV operation schedule may include instructions for deriving a charge and discharge amount of the ESS battery per time interval and a charge and discharge amount of the EV battery per time interval by using an objective function defined by a cost of purchasing grid power.

[0186] The objective function may include defined constraints, the defined constraints including at least one of the following: a first condition regarding a balance between power supply and power consumption, a second condition regarding a state of charge (SOC) based on a charge / discharge efficiency of an ESS battery, a third condition regarding a limit charge amount of the ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of the charge / discharge state of the ESS battery. In this article, the constraints may also include at least one of the following: a sixth condition regarding the SOC according to the charge / discharge efficiency of an EV battery, a seventh condition regarding a limit charge amount of an EV battery, an eighth condition regarding a limit output of a bidirectional EV charger, and a ninth condition regarding binarization of the charge / discharge state of the bidirectional EV charger.

[0187] The instructions for collecting basic information may include instructions for collecting basic information including information about a power generation state and a power consumption state for a predefined first period. Herein, the instructions for establishing an ESS operation schedule and an EV operation schedule may include instructions for generating power generation prediction information and power consumption prediction information for a second period by using the collected basic information, the second period being predefined as a period after the first period; and instructions for generating the ESS operation schedule and the EV operation schedule for the second period based on the generated prediction information.

[0188] The instructions for collecting basic information may include instructions for receiving load schedule information for an on-off controllable load from a user terminal, in which a time interval for operating the load in an on state or an off state is set. Herein, the instructions for establishing an ESS operation schedule and an EV operation schedule may include instructions for generating an ESS operation schedule and an EV operation schedule based on the load schedule information.

[0189] The instructions for collecting basic information may include instructions for receiving EV schedule information from a user terminal, in which a time interval during which the EV is connected to the bidirectional EV charger is set. Herein, the instructions for establishing an ESS operation schedule and an EV operation schedule include instructions for generating an ESS operation schedule and an EV operation schedule based on the EV schedule information.

[0190] The instructions for controlling the ESS battery and the EV battery to be charged / discharged may include instructions for providing an ESS operation schedule to a power conversion device that communicates with the ESS battery and providing an EV operation schedule to a bidirectional EV charger so that the ESS battery is charged and discharged according to the ESS operation schedule and the EV battery is charged and discharged according to the EV operation schedule.

[0191] The energy management device 600 may further include an input interface device 640 , an output interface device 650 , a storage device 660 , etc. Each of the components included in the energy management device 600 may be connected through a bus 670 to communicate with each other.

[0192] Herein, the processor 610 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which a method according to an exemplary embodiment of the present invention is executed. The memory (or storage device) may be formed by at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory may be formed by at least one of a read-only memory (ROM) and a random access memory (RAM).

[0193] The operation of the method according to the exemplary embodiment of the present invention can be implemented as a code on a computer-readable program or a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices for storing data readable by a computer system. In addition, the computer-readable recording medium can be distributed in a network-connected computer system to store and execute a computer-readable program or code in a distributed manner.

[0194] Although some aspects of the present invention have been described in the context of a device, they may also be represented and described in terms of a corresponding method, where 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 represent 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 exemplary embodiments, one or more of the most important method steps may be performed by such a device.

[0195] In the foregoing, the present invention has been described with reference to exemplary embodiments thereof, but those skilled in the art will appreciate that various modifications and changes may be made to the present invention without departing from the spirit and scope of the present invention described in the appended claims.

Claims

1. An energy management device that communicates with a power grid, a power generation device, an energy storage system ESS, and a bidirectional electric vehicle EV charger, the energy management device comprising: at least one processor; as well as a memory for storing at least one instruction executed by the at least one processor, The at least one instruction includes: instructions for collecting basic information, the basic information including information on power generation status and power consumption status, and grid power cost information; instructions for establishing an ESS operation schedule for controlling charging and discharging operations of an ESS battery and an EV operation schedule for controlling charging and discharging operations of an EV battery by using the collected basic information; and Instructions for controlling the ESS battery and the EV battery to be charged / discharged according to the ESS operation schedule and the EV operation schedule.

2. The energy management device according to claim 1, wherein: The instructions for establishing the operation schedule include instructions for deriving a charge and discharge amount of the ESS battery for each time interval and a charge and discharge amount of the EV battery for each time interval that minimizes a cost of purchasing grid power.

3. The energy management device according to claim 1, wherein: The instructions for establishing the ESS operation schedule and the EV operation schedule include instructions for deriving a charge and discharge amount of the ESS battery per time interval and a charge and discharge amount of the EV battery per time interval by using an objective function defined by a cost of purchasing the grid power.

4. The energy management device according to claim 3, wherein: The objective function includes defined constraints, the defined constraints including at least one of a first condition regarding a balance of power supply and power consumption, a second condition regarding a state of charge SOC based on a charge / discharge efficiency of the ESS battery, a third condition regarding a limit charge amount of the ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of a charge / discharge state of the ESS battery.

5. The energy management device according to claim 4, wherein: The constraints also include at least one of: a sixth condition regarding the SOC according to the charging / discharging efficiency of the EV battery, a seventh condition regarding the limit charging amount of the EV battery, an eighth condition regarding the limit output of the bidirectional EV charger, and a ninth condition regarding the binarization of the charging / discharging state of the bidirectional EV charger.

6. The energy management device according to claim 1, wherein: The instructions for collecting the basic information include instructions for collecting basic information including information on a power generation state and a power consumption state for a predefined first period, and The instructions for establishing the ESS operation schedule and the EV operation schedule include: instructions for generating power generation prediction information and power consumption prediction information for a second period predefined as a period after the first period by using the collected basic information; and Instructions for generating an ESS operation schedule and an EV operation schedule for the second period based on the generated prediction information.

7. The energy management device according to claim 1, wherein: The instructions for collecting the basic information include instructions for receiving load schedule information for turning on and off a controllable load from a user terminal, in which a time interval for operating the load in an on state or an off state is set, and The instructions for establishing the ESS operation schedule and the EV operation schedule include instructions for generating the ESS operation schedule and the EV operation schedule based on the load schedule information.

8. The energy management device according to claim 1, wherein: The instructions for collecting the basic information include instructions for receiving EV schedule information from a user terminal in which a time interval during which an EV is connected to a bidirectional EV charger is set, and The instructions for establishing the ESS operation schedule and the EV operation schedule include instructions for generating the ESS operation schedule and the EV operation schedule based on the EV schedule information.

9. The energy management device according to claim 1, wherein: The instructions for controlling the ESS battery and the EV battery to be charged / discharged include instructions for providing the ESS operation schedule to a power conversion device that communicates with the ESS battery and providing the EV operation schedule to the bidirectional EV charger so that the ESS battery is charged and discharged according to the ESS operation schedule and the EV battery is charged and discharged according to the EV operation schedule.

10. An energy management method performed by an energy management device intercommunication with an electric power grid, an electric power generation device, an energy storage system ESS and a bidirectional electric vehicle EV charger, the energy management method comprising: collecting basic information, the basic information including information on power generation status and power consumption status, and grid power cost information; establishing an ESS operation schedule for controlling charging and discharging operations of an ESS battery and an EV operation schedule for controlling charging and discharging operations of an EV battery by using the collected basic information; as well as The ESS battery and the EV battery are controlled to be charged / discharged according to the ESS operation schedule and the EV operation schedule.

11. The energy management method according to claim 10, wherein: Establishing the operation schedule includes deriving a charge and discharge amount of the ESS battery for each time interval and a charge and discharge amount of the EV battery for each time interval that minimizes a cost of purchasing grid power.

12. The energy management method according to claim 10, wherein: Establishing the ESS operation schedule and the EV operation schedule includes deriving a charge and discharge amount of the ESS battery per time interval and a charge and discharge amount of the EV battery per time interval by using an objective function defined by a cost of purchasing the grid power.

13. The energy management method according to claim 12, wherein: The objective function includes defined constraints, the defined constraints including at least one of a first condition regarding a balance of power supply and power consumption, a second condition regarding a state of charge SOC based on a charge / discharge efficiency of the ESS battery, a third condition regarding a limit charge amount of the ESS battery, a fourth condition regarding a limit output of a power conversion device, and a fifth condition regarding binarization of a charge / discharge state of the ESS battery.

14. The energy management method according to claim 13, wherein: The constraints also include at least one of: a sixth condition regarding the SOC according to the charging / discharging efficiency of the EV battery, a seventh condition regarding the limit charging amount of the EV battery, an eighth condition regarding the limit output of the bidirectional EV charger, and a ninth condition regarding the binarization of the charging / discharging state of the bidirectional EV charger.

15. The energy management method according to claim 10, wherein: collecting the basic information includes collecting basic information including information about a power generation state and a power consumption state for a predefined first period, and Establishing the ESS operation schedule and the EV operation schedule includes: generating power generation prediction information and power consumption prediction information for a second period predefined as a period after the first period by using the collected basic information; and An ESS operation schedule and an EV operation schedule for the second period are generated based on the generated prediction information.

16. The energy management method according to claim 10, wherein: Collecting the basic information includes receiving load schedule information for turning on and off the controllable load from the user terminal, in which a time interval for operating the load in an on state or an off state is set, and Establishing the ESS operation schedule and the EV operation schedule includes generating the ESS operation schedule and the EV operation schedule based on the load schedule information.

17. The energy management method according to claim 10, wherein: collecting the basic information includes receiving EV schedule information from a user terminal, in which a time interval during which an EV is connected to a bidirectional EV charger is set, and Establishing the ESS operation schedule and the EV operation schedule includes generating the ESS operation schedule and the EV operation schedule based on the EV schedule information.

18. The energy management method according to claim 10, wherein: Controlling the ESS battery and the EV battery to be charged / discharged includes: providing the ESS operation schedule to a power conversion device that communicates with the ESS battery, and providing the EV operation schedule to the bidirectional EV charger, so that the ESS battery is charged and discharged according to the ESS operation schedule and the EV battery is charged and discharged according to the EV operation schedule.

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