Energy management device and energy management method

Abstract

An energy management device according to one embodiment of the present invention is an energy management device that interfaces with a power grid, a power production device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, and may include at least one processor and a memory that stores at least one instruction to be executed by the at least one processor. Here, the at least one command may include an command to collect basic information including information on the power production status and power consumption status and grid power cost information, an command to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery using the collected basic information, and an command to control the charging and discharging of the ESS battery and the EV battery in accordance with the ESS operation schedule and the EV operation schedule.

Description

[Technical Field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2023-0101159, filed with the Korean Intellectual Property Office on August 2, 2023, and all of the contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to an energy management device and an energy management method, and more particularly to an energy management device and an energy management method using such an energy management device that interfaces with a power grid, a power production device, an energy storage system, and a bidirectional electric vehicle charger. [Background technology]

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

[0004] In recent years, ESSs that work in conjunction with photovoltaic (PV) systems and electric vehicle (EV) charging systems have been proposed. The host controller of the PV-EV linked ESS is configured to appropriately distribute and supply the grid power supplied from the grid, the power produced by the PV system, and the power stored in the ESS to the load and the EV charger, and to store the remaining power in the battery system.

[0005] PV and EV linked ESSs are operated taking into consideration various factors such as the amount of power generated by the PV system, the power demands of the load and EV charger, and the state of charge of the battery. However, the most important goal for ESS users is to minimize the cost of purchasing electricity, but conventional ESS operation methods have been operated with the goal of maximizing PV power generation, maximizing battery performance, or minimizing grid power usage.

[0006] Therefore, appropriate energy management technology is needed that can enable optimal operation taking into account the amount of PV power generated, the power demands of the load and EV charger, and the battery charge state, while minimizing power purchasing costs. Summary of the Invention [Problem to be solved by the invention]

[0007] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an energy management device that can minimize the cost of purchasing grid power.

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

[0009] To achieve the above object, an energy management device according to one embodiment of the present invention is an energy management device that interfaces with a power grid, a power production device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, and may include at least one processor and a memory that stores at least one instruction to be executed by the at least one processor.

[0010] Here, the at least one command may include an command to collect basic information including information on the power production status and power consumption status and grid power cost information, an command to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery using the collected basic information, and an command to control the charging and discharging of the ESS battery and the EV battery in accordance with the ESS operation schedule and the EV operation schedule.

[0011] The command to create the operation schedule may include a command to derive the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval, which minimizes the cost of purchasing grid power.

[0012] The command to create the ESS operation schedule and the EV operation schedule may include a command to derive the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power.

[0013] The objective function may define constraints including at least one of a first condition related to the balance between power supply and power consumption, a second condition related to the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery, a third condition related to the limit charge amount of the ESS battery, a fourth condition related to the limit output of the power conversion device, and a fifth condition related to binarization of the charge / discharge state of the ESS battery. Here, the constraints may further include at least one of a sixth condition related to the state of charge (SOC) based on the charge / discharge efficiency of the EV battery, a seventh condition related to the limit charge amount of the EV battery, an eighth condition related to the limit output of the bidirectional EV charger, and a ninth condition related to binarization of the charge / discharge state of the bidirectional EV charger.

[0014] The instruction to collect basic information may include an instruction to collect basic information including information regarding a power production state and a power consumption state for a predefined first period, wherein the instruction to create an ESS operation schedule and an EV operation schedule may include an instruction to generate power production forecast information and power consumption forecast information for a predefined second period that is a period after the first period, using the collected basic information, and an instruction to generate an ESS operation schedule and an EV operation schedule for the second period based on the generated forecast information.

[0015] The command to collect basic information may include a command to receive, from a user terminal, load schedule information in which time periods for operating in an on state or an off state are set for on / off controllable loads. Here, the command to create an ESS operation schedule and an EV operation schedule may include a command to generate an ESS operation schedule and an EV operation schedule based on the load schedule information.

[0016] The command to collect basic information may include a command to receive, from the user terminal, EV schedule information in which a time period during which the EV will be connected to the bidirectional EV charger is set. Here, the command to create an ESS operation schedule and an EV operation schedule may include a command to generate an ESS operation schedule and an EV operation schedule based on the EV schedule information.

[0017] The instructions for controlling the ESS battery and the EV battery to be charged and discharged may include instructions for providing the ESS operation schedule to a power conversion device interfaced with the ESS battery and providing the EV operation schedule to a bidirectional EV charger so that the ESS battery is charged and discharged in accordance with the ESS operation schedule and the EV battery is charged and discharged in accordance with the EV operation schedule.

[0018] To achieve yet another object, an energy management method according to one embodiment of the present invention is an energy management method using an energy management device that is linked to a power grid, a power production device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, and includes the steps of collecting basic information including information on power production status and power consumption status and grid power cost information, using the collected basic information to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery, and controlling the ESS battery and the EV battery to be charged and discharged in accordance with the ESS operation schedule and the EV operation schedule.

[0019] The step of creating an operation schedule may include a step of deriving the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval that minimizes the purchasing cost of grid power.

[0020] The step of creating an ESS operation schedule and an EV operation schedule may include a step of deriving the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power.

[0021] The objective function may define constraints including at least one of a first condition related to the balance between power supply and power consumption, a second condition related to the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery, a third condition related to the limit charge amount of the ESS battery, a fourth condition related to the limit output of the power conversion device, and a fifth condition related to binarization of the charge / discharge state of the ESS battery. Here, the constraints may further include at least one of a sixth condition related to the state of charge (SOC) based on the charge / discharge efficiency of the EV battery, a seventh condition related to the limit charge amount of the EV battery, an eighth condition related to the limit output of the bidirectional EV charger, and a ninth condition related to binarization of the charge / discharge state of the bidirectional EV charger.

[0022] The step of collecting basic information may include collecting basic information including information on a power production state and a power consumption state for a predefined first period, wherein the step of creating an ESS operation schedule and an EV operation schedule may include generating power production forecast information and power consumption forecast information for a predefined second period that follows the first period using the collected basic information, and generating an ESS operation schedule and an EV operation schedule for the second period based on the generated forecast information.

[0023] The step of collecting basic information may include a step of receiving, from a user terminal, load schedule information in which time periods for operating in an on state or an off state are set for on / off controllable loads. Here, the step of creating an ESS operation schedule and an EV operation schedule may include a step of generating an ESS operation schedule and an EV operation schedule based on the load schedule information.

[0024] The step of collecting basic information may include a step of receiving, from the user terminal, EV schedule information in which a time period during which the EV will be connected to the bidirectional EV charger is set. Here, the step of creating an ESS operation schedule and an EV operation schedule may include a step of generating an ESS operation schedule and an EV operation schedule based on the EV schedule information.

[0025] The step of controlling the ESS battery and the EV battery to be charged and discharged may include the steps of providing the ESS operation schedule to a power conversion device interlocked with the ESS battery and providing the 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. [Effects of the Invention]

[0026] According to the above-described embodiment of the present invention, an operation schedule for the ESS and EV charger that can minimize the cost of purchasing grid power is derived, and the ESS and EV charger are controlled according to the derived operation schedule, thereby minimizing the operation cost of the PV and EV linked ESS. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a block diagram of an energy storage system to which the present invention may be applied. [Figure 2] 1 illustrates an example of an energy storage system to which the present invention may be applied. [Figure 3] FIG. 1 is a flow diagram of an energy management method according to an embodiment of the present invention. [Figure 4] FIG. 2 is a flow diagram of an operation schedule creation method according to an embodiment of the present invention. [Figure 5] 10 is an example of a screen of a user terminal for explaining EV schedule information according to an embodiment of the present invention. [Figure 6] 10 is an example of a screen of a user terminal for explaining load schedule information according to an embodiment of the present invention. [Figure 7] 1 is a block diagram of an energy management device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] While the present invention can be modified in various ways and can have various embodiments, specific embodiments are shown by way of example in the drawings and will be described in detail in the detailed description. However, it is understood that this is not intended to limit the present invention to the specific embodiments, but rather to include all modifications, equivalents, and alternatives that fall within the spirit and technical scope of the present invention. Similar reference numerals are used to refer to similar components throughout the various drawings.

[0029] Terms such as first, second, A, and B may be used to describe various components, but the components are not limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be designated as a second component, and similarly, a second component may be designated as a first component, without departing from the scope of the present invention. The term "and / or" includes a combination of multiple associated listed items or any one of multiple associated listed items.

[0030] When a component is referred to as being "coupled" or "connected" to another component, it is understood that the component may be directly coupled or connected to the other component, but that there may be other components in between. Conversely, when a component is referred to as being "directly coupled" or "directly connected" to another component, it is understood that there are no other components in between.

[0031] The terms used in this application are merely used to describe specific embodiments and are not intended to limit the present invention. The singular expressions include the plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and are understood not to preclude the presence or additional possibility of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0032] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this invention pertains. Terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted as having an ideal or overly formal meaning unless expressly defined in this application.

[0033] Some terms used in this specification are defined as follows:

[0034] 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 [%].

[0035] The power limit indicates the limit of power that can be output, which is set in advance by the battery manufacturer according to the battery state or according to the SOC. The power limit may be divided into a charge output limit and a discharge output limit depending on whether the battery is being charged or discharged.

[0036] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0037] FIG. 1 is a block diagram of an energy storage system to which the present invention may be applied.

[0038] The energy management device 600 may be coupled to the grid 100, the load 200, the power production device 300, an electric vehicle (EV) charger 400, and an energy storage system 500.

[0039] The energy storage system 500 is electrically connected to the grid 100 and the power production device 300, and can receive and store power from the grid 100 and the power production device 300.

[0040] The energy storage system 500 is electrically connected to the load 200 and the EV charger 400, and can supply power stored in a battery (hereinafter referred to as an ESS battery) configured in the energy storage system to the load 200 and the EV charger 400. Meanwhile, the load 200 is electrically connected to the grid 100 and the power production device 300, and may be supplied with power from the grid 100 and the power production device 300.

[0041] The power generating device 300 is a device that generates power using a power generating device, and may be configured to include at least one of a power generating device that uses sunlight, solar heat, wind power, and geothermal power. However, the type of the power generating device 300 is not an essential component of the present invention, and the scope of the present invention is not limited to these individual devices.

[0042] The EV charger 400 may be electrically connected to the grid 100 , the power generating device 300 , and the energy storage system 500 , and may receive power from the grid 100 , the power generating device 300 , and the energy storage system 500 .

[0043] In the embodiment, the EV charger 400 may correspond to a bidirectional EV charger. In this case, the EV charger 400 may charge a battery included in the EV (hereinafter, referred to as an EV battery) using power supplied from an external source and discharge power stored in the EV battery to the outside. In other words, when the EV is connected to the EV charger 400, the bidirectional EV charger and the EV battery may function similarly to the energy storage system 500 according to the present invention.

[0044] When the EV charger 400 is configured as a bidirectional charger, the EV charger 400 can supply the power stored internally to the load 200 and the energy storage system 500 .

[0045] The energy management device 600 may be configured to be connected to one or more of the load 200, the power production device 300, the EV charger 400, and the energy storage system 500 via a network to transmit and receive data to and from each other.

[0046] The energy management device 600 may be configured to be included within the energy storage system 500, or may be separately provided outside the energy storage system 500. For example, the energy management device 600 may be embodied to be included in a Home Energy Management System (HEMS), which is a top-level control system of a residential ESS, or may be embodied to be included in a server of an ESS management company and connected to the HEMS via a network.

[0047] The energy management device 600 can collect one or more 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 create an operation schedule for optimal operation of the energy storage system 500 and the EV charger 400 using the collected information. Here, the energy management device 600 can create an ESS operation schedule for controlling the energy storage system 500 and an EV operation schedule for controlling the EV charger 400 using a predetermined operation schedule generation algorithm.

[0048] The operation schedule may include a charge / discharge amount (or a reference power amount) for each time interval. Specifically, the ESS operation schedule may include a charge / discharge amount of the ESS battery for each time interval, and the EV operation schedule may include a charge / discharge amount of the EV battery for each time interval.

[0049] The energy management device 600 transmits the created ESS operation schedule to the battery charge / discharge control device of the energy storage system 500, so that the ESS battery can be controlled to be charged / discharged in accordance with the ESS operation schedule.

[0050] Furthermore, energy management device 600 can transmit the created EV operation schedule to EV charger 400, so that the charging and discharging of the EV battery can be controlled in accordance with the EV operation schedule.

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

[0052] Referring to FIG. 2, the energy storage system 500 may include an ESS battery 510 that stores power, and an inverter 520 that controls the charging and discharging operations of the ESS battery 510.

[0053] The ESS battery 510 may be implemented in a form in which a number of battery packs constitute a battery rack, and a number of battery racks constitute a battery bank. Here, the battery pack may also be called a battery module depending on the device or system in which the battery is used.

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

[0055] The inverter 520 is also called a power conditioning system (PCS) or a power conversion system (PCS), and can control the power supplied to the battery from the outside and the power supplied from the battery to the outside.

[0056] The inverter 520 may include a power management system (PMS), and the energy management device 600 may be configured to communicate with the power management system of the inverter 520 to transmit and receive data to and from the power management system.

[0057] The load 200 may be configured to include a plurality of loads 200-1 to 200-N. Here, at least some of the loads 200-1 to 200-N may be first loads that cannot be turned on or off, and the remaining part may be second loads that can be turned on or off.

[0058] The first load may refer to a load that cannot be turned off or to a load to which power cannot be cut off under the control of the energy management device. The second load may refer to a load that can be turned off or to which power can be cut off under the control of the energy management device. Here, the second load may be defined based on a selection signal input by a user.

[0059] The PV system may include a PV module 310 (e.g., a solar panel) and a PV inverter 320, which is an AC / DC inverter, and the AC terminals of the PV inverter 320 and the AC terminals of the inverter 520 of the energy storage system may be connected to an AC link.

[0060] The EV charger may correspond to the bidirectional EV charger 420. Here, the bidirectional EV charger 420 may be configured to include an AC / DC inverter, and an AC terminal may be connected to an AC link.

[0061] The bidirectional EV charger 420 can control the charging and discharging operations of the EV battery included in the EV 410 .

[0062] The energy management device 600 is a higher-level controller for the grid, multiple loads, the PV system, the bidirectional EV charger, and the energy storage system, and may be configured to collect status information of each component 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.

[0063] The energy management device 600 can create an operation schedule that can minimize the grid power purchasing cost based on one or more of the charge / discharge amount of the ESS battery, the charge / discharge amount of the EV battery, the power generation amount of the PV, and the power consumption amount of the load. Here, the energy management device 600 can create an ESS operation schedule for controlling the energy storage system 500 and an EV operation schedule for controlling the EV charger 400 using a predetermined objective function and constraint conditions.

[0064] The energy management device 600 may be configured to be connected to a user terminal 700 via a network to transmit and receive data to and from the user terminal 700 .

[0065] The user terminal 700 may refer to a computing device used by an owner or manager of an energy storage system, and may correspond to, for example, a personal computer (PC), a mobile phone, or a tablet PC.

[0066] The energy management apparatus 600 may receive load schedule information for the second loads from the user terminal 700. Here, the load schedule information may include information regarding time periods during which each of the second loads operates in an on state or an off state, which is set by the user for each of the second loads.

[0067] The energy management apparatus 600 can control the on / off of the second load based on the load schedule information received from the user terminal 700. For example, when load schedule information including [load 4, off at 14:00, on at 16:00] is received, the energy management apparatus 600 can turn off the power to load 4 or cut off the power supply to load 4 at 14:00. Thereafter, the energy management apparatus 600 can turn on the power to load 4 or cancel the cut-off of the power supply to load 4 at 16:00.

[0068] The energy management apparatus 600 can receive EV schedule information for the EV 410 from the user terminal 700. Here, the EV schedule information can include information about a time period during which the EV is connected to the bidirectional EV charger, which is set by the user. For example, the energy management apparatus 600 can receive EV schedule information including [EV connection time, 17:00 to 19:00, 21:00 to 24:00] from the user terminal 700.

[0069] The load schedule information and EV schedule information received from the user terminal 700 may be used as basic information in the process of creating an ESS operation schedule and an EV operation schedule.

[0070] The energy management device 600 transmits the created ESS operation schedule to the inverter 520 of the energy storage system 500, and the inverter 520 may control the charge / discharge operation of the ESS battery 510 according to the ESS operation schedule. For example, the inverter 520 may receive the ESS operation schedule for a specific day from the energy management device 600 and control the charge / discharge operation of the ESS battery 510 according to the reference power for each time interval included in the ESS operation schedule.

[0071] The energy management device 600 transmits the created EV operation schedule to the bidirectional EV charger 420, and the bidirectional EV charger 420 can control the charging and discharging operation of the EV battery according to the EV operation schedule. For example, the bidirectional EV charger 420 can receive the EV operation schedule for a specific day from the energy management device 600 and control the charging and discharging operation of the EV battery according to the reference power for each time interval included in the EV operation schedule.

[0072] The energy storage system shown in Figure 2 is an AC coupled ESS in which a PV system, a bidirectional EV charger, a load, and an energy storage system are connected via an AC link. However, the present invention is also applicable to a DC coupled ESS in which the output side of the PV system, the input side of the EV charger, and the output side of the energy storage system are connected via a DC link, and the DC link is connected to one terminal of an AC / DC inverter.

[0073] FIG. 3 is a flow diagram of an energy management method according to an embodiment of the present invention.

[0074] The energy management method according to the embodiment of the present invention can be performed by an energy management device that interfaces with a power grid, a power production device, an energy storage system, and a bidirectional EV charger.

[0075] The energy management device may collect basic information for creating an operation schedule (S310), where the basic information may include information on the power production status, the power consumption status, and grid power cost information.

[0076] The energy management device can use the collected basic information to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery (S320). Here, the ESS operation schedule includes the charging and discharging amount (or reference power amount) of the ESS battery for each time interval, and the EV operation schedule includes the charging and discharging amount (or reference power amount) of the EV battery for each time interval.

[0077] In the operation schedule, the time interval may be defined in various ways as needed, for example, in 30-minute, 15-minute, or 1-minute increments. The operation schedule may include information about the operation period, for example, the operation start time may be defined as midnight on a specific day, and the operation end time may be defined as midnight on that day. The energy management device may derive an ESS operation schedule and an EV operation schedule that minimize the grid power purchasing cost using an optimization technique using an objective function.

[0078] The energy management device can control the ESS battery and the EV battery to be charged and discharged according to the operation schedule created in S320 (S330).

[0079] Specifically, the energy management device transmits the ESS operation schedule to an inverter of the energy storage system, and the inverter controls the charging and discharging operation of the ESS battery according to the charge and discharge amount for each time interval included in the ESS operation schedule. Further, the energy management device transmits the EV operation schedule to a bidirectional EV charger, and the bidirectional EV charger controls the charging and discharging operation of the EV battery according to the charge and discharge amount for each time interval included in the EV operation schedule.

[0080] In an embodiment, the energy management device may adjust the operation schedule during the process of the ESS battery and the EV battery operating according to the operation schedule, based on a difference between a predicted value used in the process of creating the operation schedule and an actual value collected during the operation according to the operation schedule.

[0081] 4 is a flow diagram of an operation schedule creation method according to an embodiment of the present invention. A specific embodiment of steps S310 to S320 in FIG. 3 will be described in detail below with reference to FIG.

[0082] The energy management device collects basic information (S410).

[0083] The basic information may include ESS battery-related parameters, EV battery-related parameters, grid power cost information, and information about power production and consumption states for a predefined first period, where the basic information may further include load schedule information and EV schedule information.

[0084] The ESS battery-related parameters may include one or more of the following for the ESS battery: capacity, upper limit of SOC, lower limit of SOC, charge / discharge efficiency of the power converter, and output limit of the power converter.

[0085] The EV battery-related parameters may include one or more of the EV battery's capacity, charge / discharge efficiency, upper limit SOC, lower limit SOC, charge / discharge efficiency of the bidirectional EV charger, and output limit of the bidirectional EV charger. Here, the energy management device may receive information regarding one or more of the upper limit SOC and lower limit SOC from the user terminal. For example, the user terminal may receive a minimum guaranteed SOC of the EV battery from a user and transmit the received 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 SOC of the EV battery.

[0086] The grid power cost information may include grid power costs for each time interval.

[0087] The information about the power production state and the power consumption state may include the amount of power generated by the power production device for each time interval and the amount of power consumed by each load for each time interval.

[0088] The first period can be defined as various ranges taking into consideration the predictive accuracy of the forecast information, and may be defined, for example, as from one year before a specific day (day n) to one day before that day (day n-1).

[0089] The energy management apparatus may generate forecast information for a second period predefined as a period following the first period using the collected basic information (S420).

[0090] The forecast information may include power production forecast information and power consumption forecast information, where the power production forecast information may include a forecast power generation amount of a power generating device for each time interval, and the power consumption forecast information may include a forecast power consumption amount of a load for each time interval.

[0091] The second period can be defined as an operation period of the operation schedule, and may be defined as, for example, from 0:00 to 24:00 on a specific day (day n).

[0092] In an embodiment, the energy management device may derive pattern information including a power production pattern and a power consumption pattern based on information on a power production state and a power consumption state included in the basic information, and generate power production forecast information and power consumption forecast information using the derived pattern information. For example, the energy management device may calculate average values ​​for power generation and power consumption for each time interval over a year and derive predicted power generation and power consumption for each time interval for a specific day.

[0093] In another embodiment, the energy management device may generate power production forecast information and power consumption forecast information using an artificial intelligence-based forecast model. For example, the forecast model may be configured to pre-train learning data related to power production status and power consumption status, and to output power production forecast information and power consumption forecast information (predicted power generation and consumption amounts for each time interval for a specific day) as output data when basic information is input as input data.

[0094] The energy management device may generate an ESS operation schedule and an EV operation schedule for the second time period based on the generated forecast information (S430). Here, the energy management device may derive the ESS operation schedule and the EV operation schedule using an objective function defined based on Mixed-Integer Linear Programming (MILP). A specific example of such an operation schedule generation method will be described in detail below.

[0095] The energy management device may derive an ESS operation schedule including the charge / discharge amount of the ESS battery for each time interval and an EV operation schedule including the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power. Here, the objective function may be defined as Equation 1 below.

number

[0096] Equation 1 is an objective function for deriving the charge / discharge amount of the ESS battery and the charge / discharge amount of the EV battery for each time interval that can minimize the grid power purchasing cost.

[0097] Here, the objective function according to Equation 1 may have one or more constraints defined.

[0098] The constraints may include one or more of: a first condition related to the balance between power supply and power consumption; a second condition related to the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery; a third condition related to the limit charge amount of the ESS battery; a fourth condition related to the limit output of the power conversion device; and a fifth condition related to the binarization of the charge / discharge state of the ESS battery. Here, the constraints may further include at least one of: a sixth condition related to the state of charge (SOC) based on the charge / discharge efficiency of the EV battery; a seventh condition related to the limit charge amount of the EV battery; an eighth condition related to the limit output of the bidirectional EV charger; and a ninth condition related to the binarization of the charge / discharge state of the bidirectional EV charger.

number

number

number

number

number

number

number

number

number

number

number

number

number

number

number

number

number

[0099] The first condition can be embodied in Equation 2, and the decision variable is

number

[0100] The second condition can be embodied in Equation 3, and functions such that the SOC of the ESS battery in the next time interval is determined based on the capacity of the ESS battery and the charge / discharge efficiency of the power conversion device.

[0101] The third condition can be embodied in Equation 4, and functions to determine the SOC of the ESS battery within a set threshold range.

[0102] The fourth and fifth conditions can be embodied in Equations 5 to 7, and the decision variables are

number

[0103] The sixth condition can be embodied in Equation 8, and functions such that the SOC of the EV battery in the next time interval is determined based on the capacity of the EV battery and the charge / discharge efficiency of the bidirectional EV charger.

[0104] The seventh condition can be embodied in Equation 9 and functions to determine the SOC of the EV battery within a set threshold range. Here, one or more of the lower and upper SOC limits of the EV battery may be set by a user. For example, the lower SOC limit of the EV battery may be defined as the minimum guaranteed SOC of the EV battery received from a user terminal. According to the operation schedule derived through the objective function reflecting the seventh condition, the EV battery can perform charging and discharging operations at or above the minimum guaranteed SOC.

[0105] The eighth and ninth conditions can be embodied in Equations 10 to 12, and the decision variables are

number

[0106] EV connection status value β reflected in Equations 10 and 11 EV may be defined as [1] for a connected state and [0] for a disconnected state. Here, the EV connection state value may be defined based on the EV schedule information received from the user terminal.

[0107] Meanwhile, when one or more second loads (loads that can be on / off controlled) are included among the plurality of loads, Equation 2 may be modified as shown in Equations 13 and 14 below.

number

number

number

number

[0108] When the loads include a first load and a second load, the energy management device may generate a predicted power consumption for the first load and a predicted power consumption for the second load in S420. Here, the first condition regarding the balance between power supply and power consumption may reflect an on / off schedule of the second load as shown in Equation 13.

[0109] The load on / off state value β reflected in Equation 14 load_n may be defined as [1] for an on state and [0] for an off state, where the on / off state value of the load may be defined based on load schedule information received from the user terminal.

[0110] The energy management device satisfies the above objective function and constraint conditions (first condition to ninth condition).

number

number

number

[0111] FIG. 5 is an example of a screen of a user terminal for explaining EV schedule information according to an embodiment of the present invention.

[0112] The energy management device can receive the minimum guaranteed SOC and EV schedule information from the user terminal, and generate an operation schedule based on the received minimum guaranteed SOC and EV schedule information.

[0113] More specifically, the user terminal may receive input of the minimum guaranteed SOC for the EV battery and EV schedule information from the user via a predetermined GUI (Graphical User Interface).

[0114] For example, as shown in Fig. 5, the user may input a specific SOC value (75%) as the minimum guaranteed SOC and EV schedule information for time periods during which the EV is connected to the bidirectional EV charger (Time 1: 00:00 to 07:00, Time 2: 17:00 to 19:00, Time 3: 21:00 to 24:00) to the user terminal. Then, the user terminal may transmit the minimum guaranteed SOC and EV schedule information input by the user to the energy management device.

[0115] The energy management device can reflect the minimum guaranteed SOC received from the user terminal in the seventh condition (Equation 9) among the constraints for deriving the operation schedule. Also, the energy management device can reflect the EV schedule information received from the user terminal in the eighth and ninth conditions (Equations 10 and 11) among the constraints for deriving the operation schedule.

[0116] The energy management device satisfies the objective function of Equation 1 and the constraint conditions (first to ninth conditions) that reflect the information received from the user terminal.

number

number

number

[0117] FIG. 6 is an example of a screen of a user terminal for explaining load schedule information according to an embodiment of the present invention.

[0118] The energy management device can receive load schedule information from a user terminal, in which time periods are set for loads that can be controlled to be on or off during operation in an on or off state, and generate an operation schedule based on the received load schedule information.

[0119] More specifically, the load schedule information for the second load may be input to the user terminal via a predetermined GUI.

[0120] For example, as shown in Fig. 6, 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 N). Thereafter, the user terminal may receive input from the user information regarding the time periods during which each of the second loads operates in an on or off state ([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]).

[0121] The user terminal can then communicate the load schedule information entered by the user to the energy management device.

[0122] The energy management device can 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 can switch load 4 from an off state to an on state at 2:00 PM and from an on state to an off state at 4:00 PM. The energy management device can also switch load 7 from an on state to an off state at 2:00 PM and from an off state to an on state at 6:00 PM.

[0123] The energy management device can reflect the load schedule information received from the user terminal in the first condition (Equations 13 and 14) among the constraints for deriving the operation schedule.

[0124] The energy management device satisfies the objective function of Equation 1 and the constraint conditions (first to ninth conditions) that reflect the information received from the user terminal.

number

number

number

[0125] FIG. 7 is a block diagram of an energy management device according to an embodiment of the present invention.

[0126] The energy management device 600 according to an embodiment of the present invention may be configured to be included in an energy storage system or may be separately provided outside the energy storage system. For example, the energy management device 600 may be embodied as being included in a HEMS, which is a top-level control system of a residential ESS, or may be embodied as being included in a server of an ESS management company and connected to the HEMS via a network.

[0127] The energy management device 600 may include at least one processor 610, a memory 620 for storing at least one instruction executed by the processor, and a transceiver 630 for communicating with a network.

[0128] The at least one instruction may include an instruction to collect basic information including information on power production status and power consumption status and grid power cost information, an instruction to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery using the collected basic information, and an instruction to control the ESS battery and the EV battery to be charged and discharged in accordance with the ESS operation schedule and the EV operation schedule.

[0129] The command to create the operation schedule may include a command to derive the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval, which minimizes the purchasing cost of grid power.

[0130] The command to create the ESS operation schedule and the EV operation schedule may include a command to derive the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power.

[0131] The objective function may define constraints including at least one of a first condition related to the balance between power supply and power consumption, a second condition related to the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery, a third condition related to the limit charge amount of the ESS battery, a fourth condition related to the limit output of the power conversion device, and a fifth condition related to binarization of the charge / discharge state of the ESS battery. Here, the constraints may further include at least one of a sixth condition related to the state of charge (SOC) based on the charge / discharge efficiency of the EV battery, a seventh condition related to the limit charge amount of the EV battery, an eighth condition related to the limit output of the bidirectional EV charger, and a ninth condition related to binarization of the charge / discharge state of the bidirectional EV charger.

[0132] The instruction to collect the basic information may include an instruction to collect basic information including information on a power production state and a power consumption state for a predefined first period, wherein the instruction to create the ESS operation schedule and the EV operation schedule may include an instruction to generate power production forecast information and power consumption forecast information for a predefined second period that follows the first period using the collected basic information, and an instruction to generate the ESS operation schedule and the EV operation schedule for the second period based on the generated forecast information.

[0133] The command to collect the basic information may include a command to receive, from a user terminal, load schedule information in which time periods for operating in an on-state or an off-state are set for on-off controllable loads. Here, the command to create the ESS operation schedule and the EV operation schedule may include a command to generate the ESS operation schedule and the EV operation schedule based on the load schedule information.

[0134] The command to collect the basic information may include a command to receive, from the user terminal, EV schedule information in which a time period during which the EV is to be connected to the bidirectional EV charger is set. Here, the command to create the ESS operation schedule and the EV operation schedule may include a command to generate the ESS operation schedule and the EV operation schedule based on the EV schedule information.

[0135] The command to control the charging and discharging of the ESS battery and the EV battery may include a command to provide the ESS operation schedule to a power conversion device linked to the ESS battery and to provide 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.

[0136] The energy management device 600 may further include an input interface device 640, an output interface device 650, a storage device 660, etc. The components included in the energy management device 600 are connected to each other by a bus 670 to communicate with each other.

[0137] Here, the processor 610 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the method according to the embodiment of the present invention is performed. The memory (or storage device) may be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory may be composed of at least one of a read-only memory (ROM) and a random access memory (RAM).

[0138] The operations of the method according to the embodiment of the present invention may be embodied as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium may include any type of storage device in which data that can be read by a computer system is stored. The computer-readable recording medium may also be distributed among computer systems connected via a network, so that the computer-readable program or code may be stored and executed in a distributed manner.

[0139] Some aspects of the invention have been described in the context of an apparatus, but they may also be described in terms of a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may be described in terms of a corresponding block or item or feature of a corresponding apparatus. Some or all of the method steps may be performed by (or using) a hardware apparatus, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps may be performed by such an apparatus.

[0140] Although the present invention has been described above with reference to preferred embodiments, those skilled in the art will understand that various modifications and variations can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. [Explanation of symbols]

[0141] 100:Grid 200: Load 300: Power production device 400:EV charger 500: Energy storage system 600: Energy management device 700: User terminal

Claims

1. 1. An energy management device interfacing with an electric power grid, an electric power production device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, comprising: at least one processor; and a memory for storing at least one instruction to be executed by said at least one processor; The at least one instruction: instructions to collect basic information including information on power production status and power consumption status and grid power cost information; An instruction to create an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery using the collected basic information; and An energy management device including instructions for controlling the ESS battery and the EV battery to be charged and discharged in accordance with the ESS operation schedule and the EV operation schedule.

2. The command to create the operation schedule includes: The energy management device according to claim 1 , further comprising instructions for deriving a charge / discharge amount of the ESS battery for each time interval and a charge / discharge amount of the EV battery for each time interval that minimizes the purchase cost of grid power.

3. The command to create the ESS operation schedule and the EV operation schedule is The energy management device according to claim 1 , comprising instructions for deriving the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power.

4. The objective function is:

4. The energy management device of claim 3, wherein constraint conditions are defined that include at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery, a third condition regarding the limit charge amount of the ESS battery, a fourth condition regarding the limit output of the power conversion device, and a fifth condition regarding the binarization of the charge / discharge state of the ESS battery.

5. The constraint is:

5. The energy management device of claim 4, further comprising at least one of a sixth condition related to a state of charge (SOC) based on charge / discharge efficiency of the EV battery, a seventh condition related to a limit charge amount of the EV battery, an eighth condition related to a limit output of the bidirectional EV charger, and a ninth condition related to binarization of the charge / discharge state of the bidirectional EV charger.

6. The instruction to collect the basic information includes: instructions for collecting baseline information including information regarding power production and consumption states for a predefined first time period; The command to create the ESS operation schedule and the EV operation schedule is instructions for generating power production forecast information and power consumption forecast information for a second time period predefined as a time period subsequent to the first time period using the collected baseline information; and The energy management device of claim 1 , further comprising instructions for generating an ESS operation schedule and an EV operation schedule for the second time period based on the generated forecast information.

7. The instruction to collect the basic information includes: receiving, from a user terminal, load schedule information in which a time period for operating an on / off controllable load in an on state or an off state is set for the on / off controllable load; The command to create the ESS operation schedule and the EV operation schedule is The energy management apparatus of claim 1 , comprising instructions for generating an ESS operating schedule and an EV operating schedule based on the load schedule information.

8. The instruction to collect the basic information includes: receiving, from a user terminal, EV schedule information in which a time period during which the EV is to be connected to the bidirectional EV charger is set; The command to create the ESS operation schedule and the EV operation schedule is The energy management device of claim 1 , further comprising instructions for generating an ESS operation schedule and an EV operation schedule based on the EV schedule information.

9. The command to control charging and discharging of the ESS battery and the EV battery is 2. The energy management device of claim 1, including instructions to provide the ESS operational schedule to a power conversion device associated with the ESS battery and to provide the EV operational schedule to the bidirectional EV charger so that the ESS battery is charged and discharged in accordance with the ESS operational schedule and the EV battery is charged and discharged in accordance with the EV operational schedule.

10. 1. An energy management method by an energy management device interfacing with a power grid, a power production device, an energy storage system (ESS), and a bidirectional electric vehicle (EV) charger, the method comprising: collecting basic information including information on power production status and power consumption status and grid power cost information; Using the collected basic information, creating an ESS operation schedule for controlling the charging and discharging operation of the ESS battery and an EV operation schedule for controlling the charging and discharging operation of the EV battery; and An energy management method comprising the step of controlling the ESS battery and the EV battery to be charged and discharged in accordance with the ESS operation schedule and the EV operation schedule.

11. The step of creating an operation schedule includes: The energy management method according to claim 10, further comprising the step of deriving a charge / discharge amount of the ESS battery for each time interval and a charge / discharge amount of the EV battery for each time interval that minimizes the purchase cost of grid power.

12. The step of creating the ESS operation schedule and the EV operation schedule includes: The energy management method according to claim 10, further comprising a step of deriving the charge / discharge amount of the ESS battery for each time interval and the charge / discharge amount of the EV battery for each time interval using an objective function defined as the purchasing cost of grid power.

13. The objective function is: The energy management method of claim 12, wherein constraint conditions are defined that include at least one of a first condition regarding the balance between power supply and power consumption, a second condition regarding the state of charge (SOC) based on the charge / discharge efficiency of the ESS battery, a third condition regarding the limit charge amount of the ESS battery, a fourth condition regarding the limit output of the power conversion device, and a fifth condition regarding the binarization of the charge / discharge state of the ESS battery.

14. The constraint is:

14. The energy management method according to claim 13, further comprising at least one of a sixth condition related to a state of charge (SOC) based on the charge / discharge efficiency of the EV battery, a seventh condition related to a limit charge amount of the EV battery, an eighth condition related to a limit output of the bidirectional EV charger, and a ninth condition related to binarization of the charge / discharge state of the bidirectional EV charger.

15. The step of collecting basic information includes: collecting baseline information including information regarding power production and consumption states for a predefined first time period; The step of creating the ESS operation schedule and the EV operation schedule includes: generating power production forecast information and power consumption forecast information for a second period predefined as a period subsequent to the first period using the collected basic information; and The energy management method according to claim 10 , further comprising generating an ESS operation schedule and an EV operation schedule for the second period based on the generated forecast information.

16. The step of collecting basic information includes: receiving load schedule information from a user terminal, in which a time period for operating an on-state or an off-state is set for the on / off controllable load; The step of creating the ESS operation schedule and the EV operation schedule includes: The energy management method of claim 10 , comprising generating an ESS operation schedule and an EV operation schedule based on the load schedule information.

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

18. The step of controlling the ESS battery and the EV battery to be charged and discharged includes:

11. The energy management method of claim 10, comprising providing the ESS operation schedule to a power conversion device associated with the ESS battery and providing the EV operation schedule to the bidirectional EV charger such that the ESS battery is charged and discharged in accordance with the ESS operation schedule and the EV battery is charged and discharged in accordance with the EV operation schedule.

Images