Energy storage system linked to solar power generation system and electric vehicle charging system, and its operation method

Abstract

An energy storage system according to an embodiment of the present invention may include a battery system including one or more batteries, a power conditioning system (PCS) that controls power of the battery system, and a power management controller (PMS) that collects status information regarding one or more of a grid, a PV system, an EV charging system, the battery system, and the PCS, and controls power of the PV system, the EV charging system, and the battery system based on the collected status information.

Description

[Technical Field]

[0001] This application claims the benefit of the filing date of Korean Patent Application No. 10-2022-0077229, filed with the Korean Intellectual Property Office on June 24, 2022, 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 storage system and an operation method thereof, and more particularly to an energy storage system that interfaces with a solar power generation system and an electric vehicle charging system, a power management control device, and a control method for the energy storage system. [Background technology]

[0003] An energy storage system (ESS) is a system that connects renewable energy, batteries that store power, and existing grid power. As smart grids and renewable energy become more widespread and emphasis is placed on the efficiency and stability of power systems, the demand for energy storage systems is increasing to regulate power supply and demand and improve power quality.

[0004] In recent years, the penetration rate of solar power generation systems has increased significantly due to renewable energy policies. However, this has led to an increase in the frequency of output curtailment, which prevents solar power generation systems from supplying electricity to the grid due to an excess supply of electricity from solar power generation systems.

[0005] To minimize energy loss due to output restrictions, a technology has been proposed that connects a solar power generation system to an electric vehicle charging system and charges electric vehicles using solar power. To ensure a stable supply of charging power, an energy storage system (ESS) must be connected to the grid. An energy storage system stores grid power and solar power at appropriate times and discharges the stored power when needed to supply power for electric vehicles, thereby mitigating the output variability of the solar power generation system. When connecting such an energy storage system to a solar power system and an electric vehicle charging system, an appropriate control method is required that takes into account various factors such as peak generation, output restrictions, and power purchasing costs. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide an energy storage system that can be connected to a grid, a solar power generation system, and an electric vehicle charging system.

[0007] Another object of the present invention to solve the above problems is to provide a method for controlling such an energy storage system.

[0008] Another object of the present invention to solve the above problems is to provide a power control device for controlling the operation of such an energy storage system. [Means for solving the problem]

[0009] To achieve the above object, an energy storage system according to one embodiment of the present invention includes a battery system including one or more batteries, a power conditioning system (PCS) that controls the power of the battery system, and a power management controller (PMS) that collects status information regarding one or more of a grid, a PV system, an EV charging system, a battery system, and the PCS, and controls the power of the PV system, the EV charging system, and the battery system based on the collected status information.

[0010] The power management controller may control the power of the PV system, the EV charging system, and the battery system according to a control mode corresponding to the current time among a plurality of predefined control modes. In this case, the plurality of control modes may be defined to correspond to load levels for each predefined time period based on the level of the grid power purchase cost.

[0011] The plurality of control modes may include a first control mode defined corresponding to a maximum load section, a second control mode defined corresponding to a heavy load section, and a third control mode defined corresponding to a light load section.

[0012] The power management controller can control the power supplier to the EV, the power supplier to the battery system, the charging and discharging of the battery system, and the output limit (Curtailment) of the PV system based on the EV charge amount, PV power generation amount, and battery status information.

[0013] The power management controller can control the system so that the EV is charged with the power generated by the PV system and the battery is charged with the remaining power after the EV is charged, if the EV charging amount does not exceed the PV power generation amount. In this case, if the battery is fully charged, the power management controller can control the system so that the power generated by the PV system is not supplied to the grid.

[0014] The power management controller can control the PV system to charge the battery with the power generated by the PV system when the PV system is generating power and there is no EV charging demand. In this case, if the battery is fully charged, the power management controller can control the PV system so that the power generated by the PV system is not supplied to the grid.

[0015] If the current time corresponds to the maximum load section, the power management controller can control the EV to be charged with the power generated by the PV system and the battery system to charge the EV with the stored power if the EV charging amount exceeds the PV power generation amount. In this case, if the battery state of charge is below a predefined threshold SOC, the power management controller can control the EV to be charged with grid power to charge the EV with the stored power.

[0016] If the current time corresponds to a heavy load section, the power management controller can control the EV to be charged with the power generated by the PV system and the battery system to charge the insufficient EV charge if the EV charge exceeds the PV power generation. In this case, if the battery state of charge is below a predefined threshold SOC, the power management controller can control the EV to be charged with grid power to charge the insufficient EV charge, and can control the battery to be charged with grid power within a peak limit range.

[0017] If the current time falls within the light load section, the power management controller can control the EV to be charged with the power generated by the PV system and the battery system to be put into standby mode if the EV charging amount exceeds the PV power generation amount, and can control the EV to be charged with the power generated by the PV system and the grid power to make up for the shortfall in the EV charging amount.

[0018] If the current time falls within the maximum load section or the heavy load section, the power management controller may control the EV to be charged with the stored power of the battery system if the PV system is not generating power, and may control the EV to be charged with grid power if the battery's state of charge is below a predefined threshold SOC.

[0019] If the current time corresponds to a light load section, the power management controller can control the PV system to charge the EV with grid power to make up for the shortfall in the EV charge amount if the PV system is not generating power, and can control the battery system to a standby state.

[0020] If the current time corresponds to a heavy load section, the power management controller can control the battery to be charged with grid power within the peak limit range if there is no EV charging demand and the PV system is not generating power. In this case, if the battery's state of charge exceeds a predefined threshold SOC, the battery system can be controlled to be in a standby state.

[0021] The power management controller checks the cumulative usage of grid power at predetermined unit time intervals, and if it determines that the cumulative usage of grid power has exceeded a predefined peak limit value, causing a peak, the power management controller can control the battery system to discharge its stored power.

[0022] To achieve another object described above, one embodiment of the present invention provides a method for controlling an energy storage system, which includes a battery system, a power conditioning system (PCS), and a power management controller (PMS), and is linked to a grid, a solar power generation system, and an electric vehicle charging system, and includes the steps of: the power management controller collecting status information regarding one or more of the grid, the PV system, the EV charging system, the battery system, and the PCS; and the power management controller controlling power of the PV system, the EV charging system, and the battery system based on the collected status information.

[0023] The step of controlling the power may include determining a control mode corresponding to a current time from among a plurality of predefined control modes, and controlling the power of the PV system, the EV charging system, and the battery system according to the determined control mode. In this case, the plurality of control modes may be defined corresponding to load levels for each predefined time period based on the level of grid power purchase costs, and may include a first control mode defined corresponding to a maximum load zone, a second control mode defined corresponding to a heavy load zone, and a third control mode defined corresponding to a light load zone.

[0024] The step of collecting the status information may include a step of monitoring the charge amount of the EV, the amount of PV power generation, and battery status information, where the step of controlling the power may include a step of controlling a power supplier to the EV, a power supplier to the battery system, charging / discharging of the battery system, and output curtailment of the PV system based on the collected status information.

[0025] The step of controlling the power may include a step of controlling the EV to be charged with the power generated by the PV system if the EV charging amount does not exceed the PV power generation amount, and charging the battery with the remaining power after the EV charging. In this case, if the battery is fully charged, the step of controlling the power may include a step of controlling the PV system so that the power generated by the PV system is not supplied to the grid.

[0026] The step of controlling the power may include a step of controlling the battery to be charged with the power generated by the PV system if the PV system is in a power generating state and there is no EV charging request. In this case, if the battery is in a fully charged state, the step of controlling the power may include a step of controlling the power generated by the PV system not to be supplied to the grid.

[0027] When the current time corresponds to the maximum load section, the step of controlling the power may include controlling the EV to be charged with power generated by the PV system and the battery system to charge the insufficient amount of the EV charge if the EV charge amount exceeds the PV power generation amount. In this case, when the state of charge of the battery is equal to or lower than a predetermined threshold SOC, the step of controlling the power may include controlling the EV to be charged with grid power to charge the insufficient amount of the EV charge.

[0028] When the current time corresponds to a heavy load section, the step of controlling power may include controlling the EV to be charged with power generated by the PV system and charging the battery with stored power from the battery system if the EV charging amount exceeds the PV power generation amount. In this case, when the battery state of charge is equal to or lower than a predetermined threshold SOC, the step of controlling power may include controlling the EV to be charged with grid power to make up the EV charging amount and charging the battery with grid power within a peak limit range.

[0029] When the current time corresponds to the light load section, the step of controlling the power may include the steps of, if the EV charging amount exceeds the PV power generation amount, charging the EV with the power generated by the PV system, charging the shortfall in the EV charging amount with grid power, and controlling the battery system to a standby state.

[0030] If the current time corresponds to the maximum load section or the heavy load section, the step of controlling the power may include controlling the EV to be charged with stored power in the battery system if the PV system is not generating power. In this case, if the state of charge of the battery is equal to or lower than a predetermined threshold SOC, the step of controlling the power may include controlling the EV to be charged with grid power.

[0031] If the current time corresponds to the light load section, the step of controlling the power may include the steps of controlling the PV system to charge the EV with grid power to make up for the shortfall in the EV charge amount if the PV system is not in a power generation state, and controlling the battery system to a standby state.

[0032] If the current time corresponds to the heavy load section, the step of controlling the power may include controlling the battery to be charged with grid power within a peak limit range if there is no EV charging demand and the PV system is not in a power generation state. In this case, if the state of charge of the battery exceeds a predefined threshold SOC, the step of controlling the power may include controlling the battery system to a standby state.

[0033] The step of controlling the power may include a step of checking the cumulative usage of grid power every predetermined unit time, and controlling the stored power of the battery system to discharge if it is determined that the cumulative usage of grid power exceeds a predefined peak limit value, causing a peak.

[0034] To achieve the above and other objects, a power management control device according to one embodiment of the present invention is a power management control device located in an energy storage system that includes a battery system and a power conditioning system (PCS) and is linked to a grid, a solar power generation system, and an electric vehicle charging system, and can include at least one processor and a memory that stores at least one instruction that is executed by the at least one processor.

[0035] Here, the at least one instruction may include an instruction to collect status information regarding one or more of the grid, the PV system, the EV charging system, the battery system, and the PCS, and an instruction to control power of the PV system, the EV charging system, and the battery system based on the collected status information.

[0036] The instructions to control power may include instructions to determine a control mode corresponding to the current time from among a plurality of predefined control modes, and instructions to control the power of the PV system, the EV charging system, and the battery system according to the determined control mode.

[0037] The command to collect the status information may include a command to monitor the charge amount of the EV, the amount of PV power generation, and the battery status information. In this case, the command to control the power may include a command to control the power supplier to the EV, the power supplier to the battery system, the charging and discharging of the battery system, and the output limit (Curtailment) of the PV system based on the collected status information.

[0038] If the current time corresponds to the maximum load section, the command to control power may include a command to charge the EV with power generated by the PV system and charge the EV with stored power from the battery system if the EV charging amount exceeds the PV power generation amount. In this case, if the battery state of charge is below a predefined threshold SOC, the command to control power may include a command to charge the EV with grid power to charge the EV with the shortage of charge.

[0039] If the current time corresponds to a heavy load section, the command to control power may include a command to charge the EV with power generated by the PV system and charge the battery with stored power to make up for the shortfall in the EV charge if the EV charge exceeds the PV power generation. In this case, if the battery state of charge is below a predefined threshold SOC, the command to control power may include a command to charge the EV with grid power to make up for the shortfall in the EV charge and charge the battery with grid power within a peak limit range.

[0040] If the current time falls within the light load section, the power control command may include a command to charge the EV with the power generated by the PV system if the EV charging amount exceeds the PV power generation amount, control the EV to charge the shortfall in the EV charging amount with grid power, and control the battery system to a standby state.

[0041] If the current time falls within the maximum load section or the heavy load section, the command to control power may include a command to control the EV to be charged with stored power in the battery system if the PV system is not generating power. In this case, if the state of charge of the battery is equal to or lower than a predefined threshold SOC, the command to control power may include a command to control the EV to be charged with grid power.

[0042] If the current time falls within the light load section, the command to control the power may include a command to control the PV system to charge the EV with grid power to make up for the shortfall in the EV charge if the PV system is not generating power, and a command to control the battery system into standby mode.

[0043] If the current time corresponds to a heavy load section, the command to control power may include a command to control the battery to charge with grid power within a peak limit range if there is no EV charging demand and the PV system is not in a power generation state. In this case, if the battery's state of charge exceeds a predefined threshold SOC, the command to control power may include a command to control the battery system to a standby state. [Effects of the Invention]

[0044] According to the above-described embodiment of the present invention, it is possible to mitigate output variability of the solar power generation system, stably supply charging power for electric vehicles, and achieve optimal operation in terms of grid power purchase costs and energy efficiency. [Brief explanation of the drawings]

[0045] [Figure 1] 1 is a block diagram illustrating an energy storage system connected to a solar power generation system and an electric vehicle charging system according to the present invention; [Figure 2] 1 is a block diagram illustrating an energy storage system interconnected with a solar power generation system and an electric vehicle charging system according to an embodiment of the present invention. [Figure 3]FIG. 2 is a flow diagram of a control method for an energy storage system according to an embodiment of the present invention. [Figure 4] FIG. 2 is a flow diagram of a method for controlling an energy storage system operating in a maximum load zone according to an embodiment of the present invention. [Figure 5] FIG. 2 is a flow diagram of a control method for an energy storage system operating in a heavy load section according to an embodiment of the present invention. [Figure 6] FIG. 2 is a flow diagram of a control method for an energy storage system operating in a light load section according to an embodiment of the present invention. [Figure 7] 1 is a reference table for explaining a control method for peak response in an energy storage system according to an embodiment of the present invention. [Figure 8] 1 is a block diagram of a power management control device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0046] While the present invention can be modified in various ways and has various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is understood that this is not intended to limit the present invention to the specific embodiments, but rather to include all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention. Similar reference numerals are used to refer to similar components throughout the description of the various drawings.

[0047] Terms such as "first," "second," "A," and "B" may be used to describe various components, but the components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] Some terms used in this specification are defined as follows:

[0052] Nominal capacity (Nominal Capa.) refers to the capacity [Ah] of a battery set by the battery manufacturer at the time of development.

[0053] 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 [%].

[0054] A battery rack refers to the smallest single-structure system that can be monitored and controlled through a BMS by connecting pack units set by the battery manufacturer in series / parallel, and may be composed of multiple battery modules and one BPU or protection device.

[0055] A battery bank can refer to a large-scale collection of battery rack systems consisting of multiple racks connected in parallel. The battery bank BMS can monitor and control the rack BMS (RBMS) for each battery rack.

[0056] A BSC (Battery System Controller) is a device that performs top-level control for a battery system including a bank-based battery system, and can also be used as a control device in a battery system with a multi-bank level structure.

[0057] The power limit indicates the power limit preset by the battery manufacturer according to the battery condition. The rack power limit refers to the power limit (unit: [kW]) set at the rack level, and may be set based on the battery's SOC and temperature.

[0058] Output limiting can refer to the operation of cutting off power generated by a solar power generation system so that it is not supplied to the grid. Here, output limiting can be performed by turning off a PV inverter that controls the power generated by a PV module to stop PV power generation, or by supplying PV-generated power only to an energy storage system or an EV charging system and cutting off the supply to the grid.

[0059] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0060] FIG. 1 is a block diagram illustrating an energy storage system connected to a solar power generation system and an electric vehicle charging system according to the present invention.

[0061] An energy storage system (ESS) 100 according to the present invention is configured to interface with a photovoltaic (PV) system 200, an electric vehicle (EV) charging system 300, and a grid 400, as shown in FIG.

[0062] The energy storage system 100 stores power supplied from the grid 400 and power generated by the PV system 200, and can discharge the power stored in the battery to supply it to the EV charging system 300 for charging the EV.

[0063] The power generated by the PV system 200 may be transmitted to at least one of the energy storage system 100, the EV charging system 300, and the grid 400.

[0064] The EV charging system 300 can charge the EV by receiving power corresponding to the charging demand of the EV from at least one of the energy storage system 100, the PV system 200, and the grid 400.

[0065] In the present invention, the entity that controls the flow of power in the energy storage system 100, the PV system 200, and the EV charging system 300 may be a power management system (PMS) configured in the energy storage system 100. Here, the power management system (PMS) can collect status information of the battery system and PCS of the ESS, the PV system 200, and the EV charging system 300, and control the power of the battery system, the PV system 200, and the EV charging system 300 based on the collected status information.

[0066] The power management controller (PMS) can control the power of the battery system, the PV system 200, and the EV charging system 300 by transmitting control commands to the respective controllers of the battery system, the PV system 200, and the EV charging system 300.

[0067] FIG. 2 is a block diagram illustrating an energy storage system connected to a PV system and an EV charging system according to an embodiment of the present invention.

[0068] Referring to FIG. 2, an energy storage system 100 according to one embodiment of the present invention may include a battery system 110 including one or more batteries, a power conditioning system (PCS) 120 that controls the power of the battery system 110, and a power management controller (PMS) 130 that controls the power of a PV system 200, an EV charging system 300, and the battery system 110.

[0069] The battery system 110 may be typically embodied in a form in which a number of battery modules constitute a battery rack, and a number of battery racks constitute a battery bank. Here, the battery rack may also be called a battery pack depending on the device or system in which the battery is used. The battery system 110 may include a battery management system (BMS). The BMS may monitor the current, voltage, and temperature of each battery rack (or pack) under its control, calculate the SOC (Status of Charge) based on the monitoring results, and control charging and discharging.

[0070] A power conditioning system (PCS) 120 linked to the battery system 110 controls power supplied from the outside and power supplied by the battery system 110 to the outside, and may include a DC / AC inverter.

[0071] The PV system 200 may include a PV module 210 that converts solar energy into electrical energy and outputs power, and a PV inverter 220 that controls the power generated by the PV module 210. Here, the PV module 210 may be configured to include a plurality of solar panels, and the PV inverter 220 may correspond to a DC / AC inverter.

[0072] 2, the output side of the power conditioning device 120, the output side of the PV inverter 220, the input side of the EV charging system 300, and the input side of the grid 400 may be connected to an AC line. Meanwhile, the energy storage system 100 according to the present invention may also be configured to operate in conjunction with the PV system 200, the EV charging system 300, and the grid 400 in a DC coupled structure, rather than the AC coupled structure shown in FIG.

[0073] The power management controller 130 collects status information of the battery system 110, the PCS 120, the PV system 200, and the EV charging system 300, and can control the power of the battery system 110, the PV system 200, and the EV charging system 300 based on the collected status information.

[0074] The power management controller 130 can collect and monitor status information including at least one of the battery state of charge (SOC), the battery charge amount and battery discharge amount, the presence or absence of PV power generation, the PV power generation amount, the presence or absence of EV charging, the EV charge amount (or charging load), and the grid power usage amount at every predefined unit time.

[0075] The power management controller 130 generates control commands for each of the PCS 120, the PV inverter 220, and the EV charging system 300 based on the collected state information, and transmits the generated control commands to the control devices of each of the components to control the operation of each component. For example, the power management controller 130 can determine a power supplier (e.g., a battery system) corresponding to the EV charging request amount, and transmit a control command (P_EV discharge) to the control device (e.g., PCS) of the determined power supplier to supply power corresponding to the power request amount.

[0076] The operation of the power management controller 130 and the control method of the energy storage system will be described in detail below with reference to FIGS.

[0077] FIG. 3 is a flow diagram of a control method for an energy storage system according to an embodiment of the present invention.

[0078] The power management controller 130 collects status information of the battery system 110, the PCS 120, the PV system 200, and the EV charging system 300 at predetermined time intervals (S310). For example, the power management controller 130 may collect status information at five-minute intervals.

[0079] The power management controller 130 can control the power of the battery system 110, the PV system 200, and the EV charging system 300 according to a control mode corresponding to the current time among a plurality of predefined control modes.

[0080] The plurality of control modes may be defined to correspond to respective load levels for predefined time periods based on the level of the grid power purchase cost, and may include a first control mode defined to correspond to a maximum load section, a second control mode defined to correspond to a heavy load section, and a third control mode defined to correspond to a light load section.

[0081] The maximum load section may be a time period with the highest purchase cost level, the heavy load section may be a time period with a lower purchase cost level than the maximum load section, and the light load section may be a time period with a lower purchase cost level than the heavy load section. For example, 10:00 AM to 5:00 PM may be defined as the maximum load section, 9:00 AM to 10:00 AM and 5:00 PM to 12:00 PM may be defined as heavy load sections, and midnight to 9:00 AM may be defined as the light load section. Meanwhile, the load level for each time period (maximum load, heavy load, or light load) may be predefined by a grid power management organization based on various environmental factors such as season and weather, and the power management controller 130 may check the load level for each time period at a certain time point (e.g., midnight every day).

[0082] 3, the power management controller 130 checks whether the current time falls within the maximum load interval (t Max_S to t Max_E) (S320), and if so, operates in the first control mode (S330). If not, the power management controller 130 checks whether the current time falls within the heavy load interval (t Heavy_s to t Heavy_E) (S340), and if so, operates in the second control mode (S350). If not, the power management controller 130 operates in the third control mode (S360).

[0083] Meanwhile, the operations (S310 to S360) of the power management controller 130 shown in FIG. 3 can be repeatedly performed every predetermined unit time (for example, every 5 minutes).

[0084] Hereinafter, the control methods of the energy storage system in the first to third control modes will be described in detail with reference to Figures 4 to 6. Meanwhile, the parameters shown in Figures 4 to 6 are as follows.

[0085] P EV (t): EV charging amount (or EV charging demand amount) in time t P PV(t): PV power generation (or output) at time t P BAT_CH (t): ESS charging power for time t P BAT_DCH (t): ESS discharge power for time t SOC set : Threshold SOC (or target SOC) SOC MAX :Maximum SOC FIG. 4 is a flow diagram of a control method (first control mode) for an energy storage system operating in a maximum load zone according to an embodiment of the present invention.

[0086] Referring to FIG. 4, the power management controller 130 checks whether the EV is being charged based on the collected status information (S410).

[0087] First, a method for controlling the energy storage system when the EV is not in a charging state (NO in S410), that is, when there is no EV charging request, will be described.

[0088] The power management controller 130 checks the power generation state of the PV system (S411), and if the PV system is not in a power generation state (NO in S411), controls the battery system 110 to a standby state (S412).

[0089] If the PV system is in a power generating state (YES in S411), the power management controller 130 checks the charge state of the battery (S413). If the battery is not fully charged (NO in S413), the power management controller 130 controls the battery to be charged with the power generated by the PV system (S414), and if the battery is fully charged (YES in S413), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S415).

[0090] Next, a method for controlling the energy storage system when the EV is in a charging state (YES in S410), that is, when there is a required amount of EV charging, will be described.

[0091] The power management controller 130 checks whether the PV system is generating power (S420).

[0092] If the PV system is not in a power generation state (NO in S420), the power management controller 130 checks the battery's state of charge (S421). If the battery's SOC exceeds a predetermined threshold SOC (NO in S421), the power management controller 130 controls the EV to be charged with the stored power in the battery system (S422). If the battery's state of charge is equal to or less than the predetermined threshold SOC (YES in S421), the power management controller 130 charges the EV with grid power and controls the battery system 110 to a standby state (S423).

[0093] If the PV system is in a power generating state (YES in S420), the power management controller 130 compares the EV charging amount with the PV power generation amount (S430).

[0094] If the EV charging amount does not exceed the PV power generation amount (NO in S430), and if the battery is not fully charged (NO in S431), the power management controller 130 controls the EV to be charged with the power generated by the PV system and to charge the battery with the remaining power after the EV is charged (S432).If the battery is fully charged (YES in S431), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S433).

[0095] If the EV charge exceeds the PV power generation (YES in S430), the power management controller 130 checks the battery's state of charge (S440). If the battery's state of charge exceeds a predefined threshold SOC (NO in S440), the power management controller 130 controls the EV to be charged with power generated by the PV system and the battery system to charge the EV with stored power (S441). If the battery's state of charge is below the predefined threshold SOC (YES in S440), the power management controller 130 controls the EV to be charged with power generated by the PV system and the battery system to charge the EV with grid power, and places the battery system 110 in a standby state (S442).

[0096] Referring to the energy storage system control method (first control mode) shown in Figure 4, when the current time is in the maximum load section, the power management controller 130 can control power so that the EV is charged according to a priority defined in the order of PV generation power, battery system storage power, and grid power. The power management controller 130 can also control power so that the battery is charged with PV generation power. The power management controller 130 can also limit the output of the PV system if the EV charging amount does not exceed the PV generation amount and the battery cannot be charged (e.g., it is fully charged).

[0097] On the other hand, if the PV inverter is turned off due to output limitations of the PV system, the PV inverter can be controlled to be turned on if PV power generation is possible (e.g., sunlight is present), the battery is chargeable (e.g., not fully charged), and the EV is charging.

[0098] FIG. 5 is a flow diagram of a control method (second control mode) for an energy storage system operating in a heavy load section according to an embodiment of the present invention.

[0099] Referring to FIG. 5, the power management controller 130 checks whether the EV is being charged based on the collected status information (S510).

[0100] First, a method for controlling the energy storage system when the EV is not in a charging state (NO in S510), that is, when there is no EV charging request, will be described.

[0101] The power management controller 130 checks the power generation state of the PV system (S511), and if the PV system is not generating power (NO in S511), the power management controller 130 checks the battery's state of charge (S512). If the battery's state of charge is below a predefined threshold SOC (YES in S512), the power management controller 130 controls the battery to be charged with grid power within a peak limit range (S513), and if the battery's state of charge exceeds the predefined threshold SOC (NO in S512), the power management controller 130 controls the battery system 110 to a standby state (S514).

[0102] The peak limit may refer to a threshold value for the cumulative amount of grid power usage over a predefined period of time. That is, when the battery SOC is below a predetermined SOC in a state where PV power is not being generated and EV is not being charged, the battery may be charged with grid power within a range that does not exceed a predefined limit for grid power usage.

[0103] If the PV system is in a power generating state (YES in S511), the power management controller 130 checks the charge state of the battery (S515). If the battery is not fully charged (NO in S515), the power management controller 130 controls the battery to be charged with the power generated by the PV system (S516), and if the battery is fully charged (YES in S515), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S517).

[0104] Next, a method for controlling the energy storage system when the EV is in a charging state (YES in S510), that is, when there is a required amount of EV charging, will be described.

[0105] The power management controller 130 checks whether the PV system is generating power (S520).

[0106] If the PV system is not generating power (NO in S520), the power management controller 130 checks the battery's state of charge (S521). If the battery's SOC exceeds a predefined threshold SOC (NO in S521), the power management controller 130 controls the EV to be charged with stored power in the battery system (S522). If the battery's SOC is equal to or lower than the predefined threshold SOC (YES in S521), the power management controller 130 charges the EV with grid power and controls the battery system 110 to a standby state (S523).

[0107] If the PV system is in a power generating state (YES in S520), the power management controller 130 compares the EV charging amount with the PV power generation amount (S530).

[0108] If the EV charging amount does not exceed the PV power generation amount (NO in S530), and if the battery is not fully charged (NO in S531), the power management controller 130 controls the EV to be charged with the power generated by the PV system and to charge the battery with the remaining power after the EV is charged (S532).If the battery is fully charged (YES in S531), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S533).

[0109] If the EV charge exceeds the PV power generation (YES in S530), the power management controller 130 checks the battery's state of charge (S540). If the battery's state of charge exceeds a predefined threshold SOC (NO in S540), the power management controller 130 controls the EV to be charged with the power generated by the PV system and to make up for the shortfall in the EV charge with the stored power in the battery system (S541). If the battery's state of charge is equal to or lower than the predefined threshold SOC (YES ... stored power in the battery system within a predetermined peak limit value (P peak ) and the difference between the EV charging amount and the PV power generation amount (P EV (t)‐P PV (t)) (S542).

[0110] Peak limit (P peak ) is the difference between the EV charging amount and the PV power generation amount (PEV (t)‐P PV If the current is equal to or less than (t), the power management controller 130 controls the EV to be charged with the power generated by the PV system and the EV to be charged with grid power to make up for the shortfall in the EV charge, and controls the battery system to be in standby mode (S544).

[0111] Peak limit (P peak ) is the difference between the EV charging amount and the PV power generation amount (P EV (t)‐P PV If the peak limit (P (t)) is exceeded, the power management controller 130 controls the EV to be charged with the power generated by the PV system, and controls the EV to be charged with the grid power to make up for the shortfall in the EV charge amount, and controls the battery to be charged with the grid power within the peak limit range (S543). For example, peak ) is 80kWh, the EV charging amount is 50kWh, and the PV power generation amount is 20kWh, the EV is charged with the PV generated power (20kWh) and the grid power (30kWh). Here, the battery may be charged with the grid power within the margin of power (80-30=50kWh) up to the peak limit value (80kWh).

[0112] Referring to the energy storage system control method (second control mode) shown in Figure 5, when the current time is a heavy load section, the power management controller 130 can control power so that the EV is charged according to a priority defined in the order of PV generation power, battery system storage power, and grid power. The power management controller 130 can also control power so that the battery is charged according to a priority defined in the order of PV generation power and grid power. The power management controller 130 can also perform output limit control of the PV system if the EV charging amount does not exceed the PV generation amount and the battery cannot be charged (e.g., it is fully charged).

[0113] In the heavy load section, unlike the maximum load section, the battery may be charged with grid power under certain conditions. Specifically, because the cost of purchasing electricity in the heavy load section is lower than that in the maximum load section, the battery may be charged using grid power only when certain conditions are met (NO in S512, YES in S542).

[0114] FIG. 6 is a flowchart of a control method (third control mode) for an energy storage system operating in a light load section according to an embodiment of the present invention.

[0115] Referring to FIG. 6, the power management controller 130 checks whether the EV is being charged based on the collected status information (S610).

[0116] First, a method for controlling the energy storage system when the EV is not in a charging state (NO in S610), that is, when there is no EV charging request, will be described.

[0117] The power management controller 130 checks the power generation state of the PV system (S611), and if the PV system is not in a power generation state (NO in S611), controls the battery system 110 to a standby state (S612).

[0118] If the PV system is in a power generating state (YES in S611), the power management controller 130 checks the charge state of the battery (S613). If the battery is not fully charged (NO in S613), the power management controller 130 controls the battery to be charged with the power generated by the PV system (S614), and if the battery is fully charged (YES in S613), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S615).

[0119] Next, a method for controlling the energy storage system when the EV is in a charging state (YES in S610), that is, when there is a required amount of EV charging, will be described.

[0120] The power management controller 130 checks whether the PV system is generating power (S620).

[0121] If the PV system is not in a power generating state (NO in S620), the power management controller 130 charges the EV with grid power and controls the battery system 110 to a standby state (S621).

[0122] If the PV system is in a power generation state (YES in S620), the power management controller 130 compares the EV charging amount with the PV power generation amount (S630).

[0123] If the EV charging amount does not exceed the PV power generation amount (NO in S630), and if the battery is not fully charged (NO in S631), the power management controller 130 controls the EV to be charged with the power generated by the PV system and to charge the battery with the remaining power after the EV is charged (S632).If the battery is fully charged (YES in S631), the power management controller 130 controls the PV system (output limit control) so that the power generated by the PV system is not supplied to the grid (S633).

[0124] If the EV charging amount exceeds the PV power generation amount (YES in S630), the EV is charged with the power generated by the PV system, and the shortfall in the EV charging amount is charged with grid power, and the battery system 110 is controlled to be in standby mode (S642).

[0125] Referring to the energy storage system control method (third control mode) shown in Figure 6, when the current time is in a light load section, the power management controller 130 can control power so that the EV is charged according to a priority defined in the order of PV power generation and grid power. The power management controller 130 can also control power so that the battery is charged with PV power generation. The power management controller 130 can also limit the output of the PV system if the EV charging amount does not exceed the PV power generation amount and the battery cannot be charged (e.g., it is fully charged).

[0126] In the light load section, unlike the maximum load and heavy load sections, the EV is not charged with stored power in the battery, and unlike the heavy load section, the battery is not charged with grid power. This is because it is cost-effective to charge the EV using the cheapest grid power and maximize the stored power in the battery.

[0127] 7 is a reference table for explaining a control method for peak response in an energy storage system according to an embodiment of the present invention. Hereinafter, the control method for peak response according to an embodiment of the present invention will be described with reference to FIG. 7.

[0128] The power management controller 130 may check the cumulative amount of grid power usage at every predetermined unit time and determine whether a peak has occurred by comparing the cumulative amount of grid power usage with a predefined peak limit value. Here, the peak limit value may refer to a threshold value for the cumulative amount of grid power usage for a predefined time period.

[0129] If the cumulative usage of grid power exceeds a predefined peak limit, the power management controller 130 determines that a peak has occurred and controls the PV system, the EV charging system, and the battery system in a peak response control mode.

[0130] When the power management controller 130 operates in the peak response control mode due to a peak occurrence, it does not operate in the control mode corresponding to the current time (first to third control modes), but controls the EV to be charged using the stored power in the battery system.

[0131] If the peak situation is resolved (the cumulative usage of grid power is below a predefined peak limit value) by discharging the battery system in the peak response control mode, the power management controller 130 can operate in the control mode (first to third control modes) corresponding to the current time.

[0132] For example, as shown in FIG. 7, if the peak judgment value is defined as 400 kW, the cumulative usage of grid power for 15 minutes must be controlled so as not to exceed 100 kWh.

[0133] If the peak determination period is set to 5 minutes, the power management controller 130 checks the cumulative grid power usage (actual usage [kWh] in FIG. 7) through a relay (e.g., the smart meter in FIG. 2) and compares the cumulative grid power usage with the peak limit value at peak determination times (1 minute, 6 minutes, and 11 minutes) to determine whether a peak has occurred. Referring to FIG. 7, at 11 minutes into the third monitoring period, the cumulative grid power usage (78.3333 kWh) exceeds the peak limit value (73.3333 kWh), determining that a peak has occurred. In this case, the power management controller 130 operates in a peak response control mode and discharges the stored power in the battery system to prevent the cumulative grid power usage from exceeding 100 kWh for 15 minutes.

[0134] FIG. 8 is a block diagram of a power management control device according to an embodiment of the present invention.

[0135] The power management control device 800 according to an embodiment of the present invention is located in an energy storage system that interfaces with a grid, a PV system, and an EV charging system, and may include at least one processor 810, a memory 820 that stores at least one instruction to be executed by the processor, and a transceiver 830 that is connected to a network and communicates with the network.

[0136] The at least one instruction may include instructions to collect status information regarding one or more of the grid, the PV system, the EV charging system, the battery system, and the PCS, and instructions to control power of the PV system, the EV charging system, and the battery system based on the collected status information.

[0137] The instruction to control the power may include an instruction to determine a control mode corresponding to the current time from among a plurality of predefined control modes, and an instruction to control the power of the PV system, the EV charging system, and the battery system according to the determined control mode.

[0138] The command to collect the status information may include a command to monitor the charge amount of the EV, the PV power generation amount, and the battery status information. In this case, the command to control the power may include a command to control a power supplier to the EV, a power supplier to the battery system, charging / discharging of the battery system, and output curtailment of the PV system based on the collected status information.

[0139] When the current time corresponds to the maximum load section, the command to control the power may include a command to charge the EV with the power generated by the PV system and charge the EV with the stored power of the battery system if the EV charging amount exceeds the PV power generation amount. In this case, when the state of charge of the battery is equal to or lower than a predetermined threshold SOC, the command to control the power may include a command to charge the EV with grid power to charge the EV with the stored power.

[0140] If the current time corresponds to a heavy load section, the command to control the power may include a command to charge the EV with the power generated by the PV system and charge the battery with the stored power of the battery system if the EV charging amount exceeds the PV power generation amount.In this case, if the state of charge of the battery is equal to or lower than a predetermined threshold SOC, the command to control the power may include a command to charge the EV with grid power to charge the battery with grid power within a peak limit range.

[0141] If the current time corresponds to a light load section, the command to control the power may include a command to charge the EV with the power generated by the PV system if the EV charging amount exceeds the PV power generation amount, control the EV to charge the shortfall in the EV charging amount with grid power, and control the battery system to a standby state.

[0142] If the current time corresponds to a maximum load section or a heavy load section, the command to control the power may include a command to control the EV to be charged with stored power of the battery system if the PV system is not generating power. In this case, if the state of charge of the battery is equal to or lower than a predetermined threshold SOC, the command to control the power may include a command to control the EV to be charged with grid power.

[0143] If the current time corresponds to a light load section, the command to control the power may include a command to control the PV system to charge the EV with grid power to make up for the shortfall in the EV charge amount if the PV system is not in a power generation state, and a command to control the battery system to a standby state.

[0144] If the current time corresponds to a heavy load section, the command to control the power may include a command to control the battery to charge with grid power within a peak limit range if there is no EV charging demand and the PV system is not in a power generation state. In this case, if the state of charge of the battery exceeds a predefined threshold SOC, the command to control the power may include a command to control the battery system to a standby state.

[0145] The power management controller 800 may further include an input interface unit 840, an output interface unit 850, a storage unit 860, etc. The components included in the power management controller 800 are connected to each other by a bus 870 to communicate with each other.

[0146] Here, the processor 810 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).

[0147] 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.

[0148] 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.

[0149] 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]

[0150] 100 Energy Storage System (ESS) 200 Photovoltaic (PV) Systems 300 Electric Vehicle (EV) Charging System 400 grid

Claims

1. An energy storage system that interfaces with a grid, a photovoltaic (PV) system, and an electric vehicle (EV) charging system, comprising: a battery system including one or more batteries; a power conditioning system (PCS) for controlling the power of the battery system; and a power management controller (PMS) that collects status information regarding one or more of the grid, the PV system, the EV charging system, the battery system, and the PCS, and controls power of the PV system, the EV charging system, and the battery system based on the collected status information; The power management controller controls the power supplier to the EV, the power supplier to the battery system, and the output limit (Curtailment) of the PV system based on the EV's charge amount, PV power generation amount, and battery status information.

2. An energy storage system that interfaces with a grid, a photovoltaic (PV) system, and an electric vehicle (EV) charging system, a battery system including one or more batteries; a power conditioning system (PCS) for controlling the power of the battery system; and a power management controller (PMS) that collects status information regarding one or more of the grid, the PV system, the EV charging system, the battery system, and the PCS, and controls power of the PV system, the EV charging system, and the battery system based on the collected status information; the power management controller controls at least one of a power supplier to the EV, a power supplier to the battery system, and an output limitation (Curtailment) of the PV system based on information on the charge amount of the EV, the PV power generation amount, and the battery state; The power management controller An energy storage system that controls the power of the PV system, EV charging system, and battery system according to a control mode corresponding to the current time from among a plurality of predefined control modes.

3. The plurality of control modes include: The energy storage system according to claim 2 , wherein the load classes are defined corresponding to predefined time-of-day load classes based on the purchase cost classes of grid power.

4. The plurality of control modes include:

4. The energy storage system of claim 3, comprising a first control mode defined corresponding to a maximum load section, a second control mode defined corresponding to a heavy load section, and a third control mode defined corresponding to a light load section.

5. The power management controller The energy storage system according to claim 1 , further controlling charging and discharging of the battery system based on the charging amount of the EV, the PV power generation amount, and battery state information.

6. The power management controller If the amount of EV charging does not exceed the amount of PV power generation, 6. The energy storage system according to claim 5, wherein the system is controlled so that an EV is charged with power generated by the PV system and a battery is charged with remaining power after the EV is charged, but when the battery is fully charged, the system is controlled so that the power generated by the PV system is not supplied to the grid.

7. The power management controller If the PV system is generating power and there is no EV charging demand, The energy storage system according to claim 5, wherein the battery is controlled to be charged with the power generated by the PV system, but when the battery is fully charged, the power generated by the PV system is controlled not to be supplied to the grid.

8. If the current time falls within the maximum load section, The power management controller If the amount of EV charging exceeds the amount of PV power generation, 6. The energy storage system according to claim 5, wherein the EV is charged with the power generated by the PV system, and a shortfall in the EV's charge amount is charged with the stored power of the battery system, and when the state of charge of the battery is equal to or lower than a predefined threshold SOC, the shortfall in the EV's charge amount is charged with grid power.

9. If the current time falls within the heavy load section, The power management controller If the amount of EV charging exceeds the amount of PV power generation, 6. The energy storage system according to claim 5, wherein the EV is charged with power generated by the PV system, and a shortfall in the EV's charge amount is controlled to be charged with stored power of the battery system, and when the state of charge of the battery is equal to or lower than a predefined threshold SOC, the shortfall in the EV's charge amount is controlled to be charged with grid power, and the battery is controlled to be charged with grid power within a peak limit range.

10. If the current time falls within the light load section, The power management controller If the amount of EV charging exceeds the amount of PV power generation, 6. The energy storage system according to claim 5, wherein the EV is charged with power generated by the PV system, and a shortfall in the EV charge amount is charged with grid power, and the battery system is controlled to be in a standby state.

11. If the current time falls within the maximum load section or heavy load section, The power management controller If the PV system is not generating power, 6. The energy storage system of claim 5, wherein the EV is controlled to be charged with stored power of the battery system, but if the state of charge of the battery is equal to or lower than a predefined threshold SOC, the EV is controlled to be charged with grid power.

12. If the current time falls within the light load section, The power management controller If the PV system is not generating power, The energy storage system according to claim 5 , wherein the battery system is controlled to be in a standby state by controlling the grid power to charge the EV to make up for the shortfall in the amount of charge.

13. If the current time falls within the heavy load section, The power management controller If there is no EV charging demand and the PV system is not generating power, 6. The energy storage system of claim 5, wherein the battery is controlled to be charged with grid power within a peak limit range, but the battery system is controlled to enter a standby state if the state of charge of the battery exceeds a predefined threshold SOC.

14. The power management controller 6. The energy storage system according to claim 5, wherein the accumulated amount of grid power usage is checked every predetermined unit time, and when it is determined that the accumulated amount of grid power usage has exceeded a predefined peak limit value and a peak has occurred, the energy storage system is controlled to discharge the stored power of the battery system.

15. A method for controlling an energy storage system including a battery system, a power conditioning system (PCS), and a power management controller (PMS), which is in communication with a grid, a photovoltaic (PV) system, and an electric vehicle (EV) charging system, comprising: the power management controller collecting status information regarding one or more of a grid, a PV system, an EV charging system, a battery system, and a PCS, including monitoring EV charging amount, PV power generation amount, and battery status information; a step of the power management controller controlling power of the PV system, the EV charging system, and the battery system based on the collected status information, the step including controlling a power supplier for the EV, a power supplier for the battery system, and an output limit (Curtailment) of the PV system based on the collected status information; A method for controlling an energy storage system, comprising:

16. A method for controlling an energy storage system including a battery system, a power conditioning system (PCS), and a power management controller (PMS), which is linked to a grid, a photovoltaic (PV) system, and an electric vehicle (EV) charging system, comprising: the power management controller collecting status information regarding one or more of a grid, a PV system, an EV charging system, a battery system, and a PCS, including monitoring EV charging amount, PV power generation amount, and battery status information; the power management controller controlling power of the PV system, the EV charging system, and the battery system based on the collected status information, the power management controller controlling at least one of a power supplier for the EV, a power supplier for the battery system, and an output limit (Curtailment) of the PV system based on the collected status information; Including, The step of controlling power includes: determining a control mode corresponding to a current time from among a plurality of predefined control modes; and A method for controlling an energy storage system, comprising the step of controlling the power of the PV system, the EV charging system, and the battery system according to the determined control mode.

17. The plurality of control modes include: The load classes are defined in correspondence with predefined time-of-day load classes based on the grid power purchase cost classes, 17. The control method for an energy storage system according to claim 16, comprising a first control mode defined corresponding to a maximum load section, a second control mode defined corresponding to a heavy load section, and a third control mode defined corresponding to a light load section.

18. The step of controlling power includes: The method for controlling an energy storage system according to claim 15, further comprising the step of controlling charging and discharging of the battery system based on the collected state information.

19. The step of controlling power includes: If the amount of EV charging does not exceed the amount of PV power generation, 20. The method for controlling an energy storage system according to claim 18, comprising the steps of: charging an EV with power generated by the PV system; and charging a battery with remaining power after charging the EV; and controlling the PV system so that the power generated by the PV system is not supplied to a grid if the battery is fully charged.

20. The step of controlling power includes: If the PV system is generating power and there is no EV charging demand, 20. The method for controlling an energy storage system according to claim 18, comprising the step of controlling a battery to be charged with power generated by the PV system, but controlling the battery so that the power generated by the PV system is not supplied to a grid if the battery is fully charged.

21. If the current time falls within the maximum load section, The step of controlling power includes: If the amount of EV charging exceeds the amount of PV power generation, 20. The method for controlling an energy storage system according to claim 18, comprising the steps of: charging an EV with power generated by the PV system; and charging a shortfall in the EV's charge amount with stored power in a battery system; and, if the state of charge of the battery is equal to or lower than a predefined threshold SOC, controlling to charge the shortfall in the EV's charge amount with grid power.

22. If the current time falls within the heavy load section, The step of controlling power includes: If the amount of EV charging exceeds the amount of PV power generation, 20. The method for controlling an energy storage system according to claim 18, comprising the steps of: charging an EV with power generated by the PV system; and controlling to charge an insufficient amount of charge of the EV with stored power of a battery system; and, if the state of charge of the battery is equal to or lower than a predefined threshold SOC, controlling to charge the insufficient amount of charge of the EV with grid power; and controlling to charge the battery with grid power within a peak limit range.

23. If the current time falls within the light load section, The step of controlling power includes: If the amount of EV charging exceeds the amount of PV power generation, 20. The method for controlling an energy storage system according to claim 18, comprising the steps of: charging an EV with power generated by the PV system; charging a deficiency in the amount of charge of the EV with grid power; and controlling the battery system to a standby state.

24. If the current time falls within the maximum load section or heavy load section, The step of controlling power includes: If the PV system is not generating power, 20. The method of claim 18, further comprising the step of controlling the EV to be charged with stored power of the battery system, and controlling the EV to be charged with grid power if the state of charge of the battery is equal to or lower than a predefined threshold SOC.

25. If the current time falls within the light load section, The step of controlling power includes: If the PV system is not generating power, The method for controlling an energy storage system according to claim 18, comprising the step of controlling the battery system to be in a standby state by controlling the battery system so that a shortage of the EV charge amount is charged by grid power.

26. If the current time falls within the heavy load section, The step of controlling power includes: If there is no EV charging demand and the PV system is not generating power, 20. The method of claim 18, further comprising controlling the battery system to charge with grid power within a peak limit range, and controlling the battery system to a standby state if the state of charge of the battery exceeds a predefined threshold SOC.

27. The step of controlling power includes:

20. The method for controlling an energy storage system according to claim 18, further comprising: checking an accumulated amount of grid power usage for each predetermined unit time; and, if it is determined that the accumulated amount of grid power usage has exceeded a predefined peak limit value, causing a peak, controlling the battery system to discharge stored power.

28. A power management controller located in an energy storage system including a battery system and a power conditioning system (PCS), the energy storage system interfacing with a grid, a photovoltaic (PV) system, and an electric vehicle (EV) charging system, at least one processor, a memory for storing at least one instruction; The at least one instruction, when executed by the at least one processor, causes the power management controller to A power management control device that executes the method for controlling an energy storage system according to any one of claims 15 to 27.

29. A computer program for causing the power management controller to execute the method for controlling an energy storage system according to any one of claims 15 to 27.

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