WO2018074651A1 - Operating device and method for energy storage device for microgrid - Google Patents

Abstract

The present invention relates to an operating device and method for an energy storage device for a microgrid. To this end, an operating device according to an embodiment of the present invention: collects prediction data relating to a load, power generation, and an energy price for each time period and real-time operation information from a microgrid operating system; defines a minimum charge capacity of an energy storage device for each time period; creates charging and discharging schedules of the energy storage device for each time period to minimize an operation cost of a microgrid; determines an operation state of the energy storage device according to user setting information and the charging and discharging schedules; derives a command value of effective power to be output from the energy storage device; and controls an operation of the energy storage device according to the operation state and the command value of effective power.

Description

Operating device and method for energy storage device for microgrid

The present invention relates to an operating apparatus and method for an energy storage device for a microgrid (APPARATUS AND METHOD FOR OPERATING ENERGY STORAGE SYSTEM CONNECTED TO MICROGRID), and more particularly to the energy storage device can be applied to the microgrid in a stable and economical manner. It relates to an operating device and a method.

An energy storage system (ESS) is a device that can charge and discharge power as needed, such as a pumped-up power plant. Recently, due to the rapid development of power electronic technology and energy storage technology, the power system linkage of the energy storage device (ESS) is continuously increasing. The power system-linked energy storage device (ESS) can be used for various purposes, such as frequency maintenance, reduction of intermittent output of renewable energy sources, peak load reduction, electricity bill reduction, and emergency power generation.

Due to these advantages, in the past, various operating techniques and control methods using energy storage devices have been studied. For example, in the related art, load and power generation prediction, electric energy price prediction data are used, and schedule-based operation schemes for maximizing the gain generated by charging / discharging the energy storage device (ESS), and energy generated by charging / discharging Considerations have been made to consider the cost of reducing the life of the device (ESS). However, in the prior art, the following problems exist.

First, the prior arts have a problem in that they propose techniques that consider only specific rates, for example only energy rates. In general, the components of electricity rates defined in domestic and international power market rules can be classified as follows according to the factors of the rates.

-Fixed rate: A rate that is charged a fixed amount regardless of the electricity usage and pattern of the customer

-Energy rate: The rate is determined by the electric energy consumed by the customer and the time of use, and is determined by the amount of electricity used per hour, the rate of time of use (TOU), critical peak pricing (CPP), real time pricing (RTP), etc. Determined

-Maximum Power Consumption Rate: The rate determined by the maximum power consumed by the consumer over a period of time, including the national base rate, overage surcharges, and transmission / distribution system use rates in the Ontario Ontario power market.

-Peak Load Contribution Fee: The rate determined by the percentage of the peak load (maximum load) of the upper grid is the Global Adjustment Rate in Ontario Canada.

Of these, the remaining charges, except for the fixed rate, may affect different rates. If an energy storage device (ESS) is operated in a market in which multiple rates are applied, considering only a specific rate, the corresponding rate may be reduced, but other charges may increase, thereby increasing the overall electric rate. Therefore, in order to prepare the charge / discharge schedule of the energy storage device (ESS) to reduce the customer's electric charge, it is necessary to simultaneously consider the energy charge, the maximum power consumption charge, and the peak load contribution charge. However, the prior patents present a problem in that they propose a method for reducing only a specific fee (mostly an energy fee).

Second, the prior art has a problem that there is no risk management method for the prediction error. Since the capacity kWh of the energy storage device ESS is limited, the output control of the energy storage device ESS at the present time may affect the operation of the future energy storage device ESS. Therefore, in order to reduce the electric charges of customers by using the energy storage device (ESS), the output control technique of the schedule-based energy storage device (ESS) should be used. Since accurate values such as future loads, power generation, and prices cannot be known, these predicted values are used to create a charge / discharge schedule of the energy storage device (ESS). However, there may be errors in the forecasts and unforeseen damages may occur due to the errors. However, the prior art has a problem in that it does not propose a method for reducing the risk that may occur due to the error of the predicted value.

Third, there is a problem in that the prior art manually manages the state of charge (SOC). In order to use the ESS as an emergency generator, the SOC must be maintained above a certain level (minimum charge) during normal operation. However, maintaining the SOC above a certain level means that the capacity of the energy storage device (ESS) capable of charging / discharging during normal operation is reduced. As a result, the gain obtained by performing charging / discharging of the energy storage device ESS may be reduced. Therefore, in order to maximize the gain that can be obtained by charging / discharging the energy storage device (ESS), it is necessary to actively define the minimum charge amount in consideration of the load to be supplied by the emergency generator. However, in the prior art, the minimum charge amount is maintained at a constant value irrespective of the load, so that there is a problem that the efficiency is lowered.

Fourth, the prior art has a problem that the state control technology of the energy storage device (ESS) is absent. In converters, which are often used as interlocking systems of ESS, internal losses (IGBT switching losses, etc.) occur even if the output is controlled to zero. Therefore, if the charge / discharge schedule result output command value of the energy storage device (ESS) is 0, controlling the active power output of the energy storage device (ESS) to 0 causes the charge amount (SOC) to continuously decrease due to internal loss. do. In order to prevent such a phenomenon, it is necessary to perform on / off control based on the output command value of the energy storage device ESS.

Accordingly, there is a need for a new operating device and method that can solve the problems of the above-mentioned prior arts and can utilize the energy storage device (ESS) for microgrid operation more stably and economically.

In this regard, there is a Korean Patent No. 1597993 entitled Energy Storage Device.

It is an object of the present invention to provide an operating apparatus and method for an energy storage device for a microgrid that can stably and economically utilize an energy storage device (ESS) for microgrid operation.

The operating device for the microgrid energy storage device of the present invention for solving the above problems is to collect the prediction data and real-time operating information on load, power generation and energy prices for each time interval from the microgrid operating system, A schedule preparation unit defining a minimum charge amount of the energy storage device connected to the microgrid per unit, and preparing a charging and discharging schedule of the energy storage unit for each time interval to minimize the operating cost of the microgrid; A command value deriving unit for determining an operating state of the energy storage device and deriving an effective power command value to be output from the energy storage device according to user setting information and a charging and discharging schedule; And a controller for controlling the operation of the energy storage device according to the operating state and the effective power command value, wherein the schedule preparation unit minimizes the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee, and the life reduction cost of the energy storage device. The charging and discharging schedules may be prepared as much as possible.

The schedule preparation unit may further include a prediction data correction module that corrects the prediction data of the time period based on the real time price information within the time period for each time period according to a user's setting.

Also, the prediction data correction module may divide one time period into a plurality of unit time periods according to a user's setting, and step the prediction data according to at least one stepping interval for each unit time period.

In addition, the schedule preparation unit may include a minimum charge setting module for setting a minimum charge amount of the energy storage device connected to the microgrid for each time period, and the minimum charge setting module may include a minimum charge amount of the energy storage device for emergency power generation and physical energy storage. Based on the minimum charge of the device, the minimum time the energy storage device should operate as an emergency generator, the forecast data for the load, the forecast data for the generation and the rated energy capacity of the energy storage device, Can be set.

In addition, the schedule preparation unit may create a temporary charge and discharge schedule for the energy storage device by converting a charge and discharge control problem into an optimization problem and finding an optimal solution of the optimization problem.

In addition, the objective function of the optimization problem may be such that the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee, and the life reduction cost of the energy storage device are minimized.

In addition, the schedule preparation unit analyzes the charge price by time period and the temporary charge and discharge schedules, and schedules to generate the final charge and discharge schedule by distributing the temporary charge and discharge schedules so that the charge and discharge plans by time intervals are maximized. It may further include a correction module.

In addition, the schedule preparation unit defines charge prices and maximum charge amounts of individual time periods, defines time periods that are continuously in the same state as a charged state or discharged state as a set of correction time periods, and time periods belonging to each correction time period set. The final charging and discharging schedule can be generated by calculating the average power of the power and performing the calibration by comparing the average power with the time periods belonging to each set of time periods to be corrected.

In addition, the operating device for the microgrid energy storage device according to an embodiment of the present invention further includes a user interface unit used for generating user setting information, the user interface unit is detected a power failure generation signal, the upper power grid connection When the switch is closed, when an operation command of the energy storage device is input from the user, the operation signal of the energy storage device according to the operation command may be blocked and a warning message may be generated.

The user interface unit may block the operation of the microgrid associated switch and generate a warning message when the voltages of the upper power grid and the consumer power grid are not synchronized during the independent operation of the energy storage device.

Operation method for the microgrid energy storage device of the present invention for solving the above problems is a schedule creation unit, the prediction data and real-time operating information on load, power generation and energy price for each time interval from the microgrid operation system Collecting the; Defining, by the schedule preparation unit, a minimum charge amount of the energy storage device connected to the microgrid for each time period; Creating, by a schedule preparation unit, a charging and discharging schedule of the energy storage device for each time interval such that an operating cost of the microgrid is minimized; Determining, by the command value deriving unit, an operating state of the energy storage device according to the user setting information and the charging and discharging schedule, and deriving an effective power command value to be output from the energy storage device; And controlling, by the control unit, the operation of the energy storage device in accordance with the operating state and the effective power command value, wherein preparing a charge and discharge schedule of the energy storage device includes an energy charge, a maximum power consumption cost, and a peak load. The sum of the contribution fee and the cost of reducing the life of the energy storage device can be made to be minimized.

In addition, the operating method for the microgrid energy storage device according to an embodiment of the present invention by the schedule preparation unit, according to the user's setting for each time period, based on the real-time price information within the time period The method may further include correcting the prediction data.

The correcting of the prediction data of the time period may include: dividing one time period into a plurality of unit time periods according to a user's setting; And cascading the prediction data according to at least one stepping interval for each unit time period.

In addition, the step of defining the minimum charge amount of the energy storage device includes the minimum charge amount of the energy storage device for emergency power generation, the minimum charge amount of the physical energy storage device, the minimum time that the energy storage device should operate as the emergency generator, and the load. Forecast data, forecast data for power generation and rated energy capacity of the energy storage device can be made.

In addition, the charging and discharging schedule of the energy storage device may include preparing a temporary charging and discharging schedule for the energy storage device by converting a charging and discharging control problem into an optimization problem and finding an optimal solution of the optimization problem. It may include.

In addition, the objective function of the optimization problem may be such that the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee, and the life reduction cost of the energy storage device are minimized.

In addition, the charging and discharging schedule of the energy storage device may be prepared by analyzing charge prices and temporary charging and discharging schedules according to time periods, and distributing temporary charging and discharging schedules to maximize distribution of time and charge plans. The method may further include generating a final charge and discharge schedule.

In addition, the step of generating the final charge and discharge schedules define the charge price and the maximum charge amount of the individual time periods, and define the time periods that are continuously the same state as the charging state or the discharge state as a set of correction target time periods, and each correction target The average output of the time periods belonging to the time period set may be calculated, and the correction may be performed by comparing the average power and the time periods belonging to each target time period set.

In addition, the operating method for the microgrid energy storage device according to an embodiment of the present invention, when the power failure signal is detected by the user interface unit, and the upper power grid associated switch is closed, the user of the energy storage device from the user When the operation command is input, the method may further include blocking an operation signal of the energy storage device according to the operation command and generating a warning message.

In addition, the operating method for the energy storage device for a microgrid according to an embodiment of the present invention, when the voltage of the upper grid and the consumer grid is not synchronized by the user interface unit during the independent operation of the energy storage device, the microgrid Blocking the operation of the associated switch of the, may further include generating a warning message.

According to the operating device and method for an energy storage device for a microgrid according to an embodiment of the present invention, it is possible to reduce the electric bill of the microgrid by performing charging / discharging in normal times and to supply power to the microgrid with an emergency power source in an emergency. There is an advantage.

1 and 2 are conceptual diagrams of a micro operating system to which an operating apparatus and method according to an embodiment of the present invention may be applied.

3 is a block diagram of an operating device for an energy storage device for a microgrid according to an embodiment of the present invention.

4 is a block diagram of a schedule preparation unit according to an embodiment of the present invention.

5 is a conceptual diagram illustrating a method of correcting prediction data made through the prediction data correction module according to an embodiment of the present invention.

6 is a conceptual view illustrating a method of setting a minimum charge amount made through the minimum charge amount setting module according to an embodiment of the present invention.

7 is a conceptual diagram illustrating a schedule correction method performed through a schedule correction module according to an embodiment of the present invention.

8 is a flowchart illustrating a method of operating an energy storage device for a microgrid according to an embodiment of the present invention.

9 is a flowchart illustrating a charging and discharging schedule generation step according to an embodiment of the present invention.

10 is a flowchart illustrating a correction step of a temporary schedule according to an embodiment of the present invention.

11 is a flowchart of a step of deriving a command value according to an embodiment of the present invention.

12 is a conceptual diagram of a control method performed through a control step according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Here, the repeated description, well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention, and detailed description of the configuration will be omitted. Embodiments of the present invention are provided to more completely describe the present invention to those skilled in the art. Accordingly, the shape and size of elements in the drawings may be exaggerated for clarity.

First, a description will be given of a micro operating system to which an operating apparatus and method (hereinafter, an operating apparatus and method) for an energy storage device for a microgrid according to an embodiment of the present invention can be applied.

1 and 2 are conceptual diagrams of a micro operating system 10 to which an operating apparatus and method according to an embodiment of the present invention may be applied. The microgrid 20 managed by the micro operating system 10 is a microgrid connection switch 21 that can physically separate the payment meter 22 and the upper power system and the microgrid 20 used to settle electric bills. It is a small power system connected to the power system 30 through. The microgrid 20 is usually operated in connection with the upper power grid 30, the microgrid operating system 10, the status information of the microgrid 20 and the energy storage device (ESS), the power market operating system 40 Using the market price and load information provided by the weather information, weather information provided by the weather data providing system 50, such as the meteorological office, user operation information and the like to control the active power of the energy storage device (ESS) in real time. On the other hand, if a problem occurs in the upper power system by using the microgrid link switch 21 disconnects the upper power system and performs independent operation. The microgrid 20 may be a single consumer such as a home, a factory, a building, and the like, and may be a distribution system of a peripheral pressure unit.

In addition, the operating apparatus and method according to an embodiment of the present invention may be connected to the microgrid operating system 10 shown in FIG. 2 to perform an operation thereof. That is, the operating device and method according to an embodiment of the present invention can derive the state and output command value of the energy storage device (ESS) using data acquired from various data sources such as terminal data, external data, database, middleware, and the like. have. The derived command value is transmitted to the energy storage device (ESS) in the field through the communication device, and the real-time output and state control of the energy storage device (ESS) can be performed based on the command value in the energy storage device (ESS) local controller. have. Various information related to the operation of the energy storage device (ESS) (status, outputs, alarms and events, charge / discharge schedules, etc.) are displayed through the HMI. In addition, the microgrid operator may change the operation strategy (operation mode, output value, etc.) of the energy storage device (ESS) based on the displayed information, and control the devices constituting the microgrid. Finally, all the history related to the operation of the energy storage device (ESS) is stored in the database and the report management can periodically generate a history report and provide it to the user. In addition, through the operating device and the method according to an embodiment of the present invention, the energy storage device (ESS) can be largely controlled in a stopped state, a ready state and an operating state.

First, the stop state indicates an open state of mechanical switches (VCB, MCCB, etc.) connecting the energy storage device (ESS) and the microgrid. In this case, the energy storage device (ESS) is physically separated from the microgrid. Indicates. The ready state indicates a state in which all preparations for the output control (mechanical switch closed, DC stage initial charge completion, etc.) are completed, and the semiconductor switch (eg, IGBT) is all open and the output current is zero.

The operating state indicates a state in which the on / off state of the semiconductor switch is controlled to control the output of the energy storage device ESS. Such an operation state may be divided into a manual operation mode and a schedule operation mode used during a grid-connected operation, and a constant voltage / frequency operation mode and a synchronization operation mode used during an independent operation. Here, the manual operation mode represents a state of controlling the active power output of the energy storage device (ESS) to a value set by the user, and the scheduled operation mode is to reduce the electric charge in the operating process for the energy storage device (ESS) It shows a state in which the active power output of the energy storage device ESS is automatically controlled according to the charge / discharge schedule of the energy storage device ESS which is periodically created. In the constant voltage / frequency operation mode, the size and frequency of the output voltage of the energy storage device (ESS) are controlled to a value set by the user to indicate a state in which the active and reactive power balance of the microgrid is maintained during the independent operation. In addition, the synchronous operation mode of the output voltage of the energy storage device (ESS) in order to control the phase angle and magnitude of the primary (high grid) and secondary (microgrid) voltage of the microgrid-linked switch open during the independent operation. Indicates the state of controlling the phase angle and magnitude. This feature enables microgrid reconnection to uninterrupted upper systems.

3 is a block diagram of an operating device 100 for an energy storage device for a microgrid according to an embodiment of the present invention. As described above, an operating device (hereinafter, referred to as an operating device) for the microgrid energy storage device according to an embodiment of the present invention may be largely divided into six features to solve the problems of the prior art.

First, the operating device 100 according to an embodiment of the present invention is characterized by creating a charge / discharge schedule by considering various electric charges. Specifically, the operating device 100 according to an embodiment of the present invention not only considers a specific fee (for example, an energy fee) of the prior art, but also an energy fee, as well as a maximum power consumption fee and a peak charge fee. In addition, solving the optimization problem in consideration of the cost of reducing the life of the energy storage device is characterized in that the charge / discharge schedule of the energy storage device (ESS) to prepare.

Second, the operating device 100 according to an embodiment of the present invention is characterized in that the risk management for the prediction error. That is, the operating device and method according to an embodiment of the present invention corrects the prediction value of the current time period by using the past history of the current time period together with the predicted value and the real-time measured value, and is used to prepare the charge / discharge schedule and predict the current time period. The error can be reduced. In addition, the operating apparatus 100 according to an embodiment of the present invention steps the prediction data at regular intervals, and distributes the charging / discharging schedule as much as possible for the time intervals in which the charging / discharging costs of the energy charging device ESS are the same. Creating a schedule can spread the risk of error. In addition, the operating apparatus 100 according to an embodiment of the present invention may provide an environment in which an interval for stairing may be set according to a user strategy (increasing the interval, the expected value of risk and gain is reduced and the interval is increased. There is a characteristic that reducing the risk increases the expected value of risk and benefit). In addition, the operating apparatus 100 according to an exemplary embodiment of the present invention may add a condition for maintaining the charge amount SOC to an upper limit at a user setting time when the charging and discharging schedule is prepared. As a result, it is possible to secure a discharge reserve force corresponding to the prediction error.

Third, the operating device 100 according to an embodiment of the present invention is characterized by actively managing the charging amount SOC of the energy storage device ESS by using the prediction data. That is, the operating apparatus 100 according to an embodiment of the present invention actively determines the minimum charging amount for emergency power generation using the load and power generation prediction result, and uses the same in the schedule preparation to determine the charging amount that can be used during normal operation ( SOC) area can be enlarged. Accordingly, there is an advantage that can increase the economics of the operation of the energy storage device (ESS).

Fourth, the operating device 100 according to an embodiment of the present invention is characterized by automatically controlling the state of the energy storage device (ESS). If the energy storage device (ESS) is automatically operated according to a schedule in the microgrid operating system, the active power output is controlled by performing on / off control of the energy storage device (ESS) together with the active power output. The loss caused by the operation of the semiconductor switch for controlling to zero can be reduced.

Fifth, the operating device 100 according to an embodiment of the present invention can perform the control according to the user's judgment and has an advantage of preventing a user's misoperation. That is, the operating apparatus 100 according to an embodiment of the present invention expresses various acquisition information together with the charge / discharge schedule information in the user interface, and can control the energy storage device ESS based on the user determination. Can provide an environment that In addition, a protection function may be provided to prevent a user's misoperation in the user interface.

Sixth, the operating device 100 according to an embodiment of the present invention may provide an uninterruptible independent operation function. In the local control system of the energy storage device (ESS), it is possible to monitor the status of the power system for stable uninterrupted independent operation and grid linkage, and automatically change the output control mode of the energy storage device (ESS).

In order to perform the above functions, the operating device 100 according to an embodiment of the present invention includes a schedule preparing unit 110, a command value deriving unit 120, a user interface unit 130, and a control unit 140. Can be configured. In this case, the above-described configuration is divided into functions for the purpose of understanding the present invention, and may be implemented through one processing device.

The schedule generator 110 prepares a charge and discharge schedule of the energy storage device ESS. In detail, the schedule preparation unit 110 functions to create a charge and discharge schedule of the energy storage device ESS for each time interval so that the operating cost of the microgrid is minimized. As described above, if the components of electricity rates defined in the domestic and overseas power market rules are classified according to the factors of the rates, they can be largely classified into fixed rates, energy rates, maximum power consumption rates, and peak load contribution rates. All of these rates, except for the fixed rate, can affect different rates. If an energy storage device (ESS) is operated in a market in which multiple rates are applied, considering only a specific rate, the corresponding rate may be reduced, but other charges may increase, thereby increasing the overall electric rate. Therefore, in order to prepare the charge / discharge schedule of the energy storage device (ESS) to reduce the customer's electric charge, it is necessary to simultaneously consider the energy charge, the maximum power consumption charge, and the peak load contribution charge. Accordingly, the schedule preparation unit 110 generates a charging and discharging schedule such that an operating cost representing a sum of an energy fee, a maximum power consumption fee, a peak load contribution fee, and a reduction in the lifespan of an energy storage device is minimized. do.

In addition, as shown in FIG. 4, the schedule preparation unit 110 may generate the prediction data correction module 111, the minimum charge amount setting module 112, the initial schedule preparation module 113, and the like. It may be configured to include a schedule correction module 114.

The prediction data correction module 111 functions to correct an error that may exist in prediction data used to prepare a charge and discharge schedule. In detail, the prediction data correction module 111 may correct the prediction data for each time interval according to the setting information set by the user, and may perform a function of stairizing the prediction data. First, a description will be given of a method of correcting prediction data for each time period made through the prediction data correction module 111.

Typically, the settlement price in a Real-Time Pricing (RTP) plan is calculated and known after operating the actual power market. Therefore, since the actual settlement price is not known at the time of operation, it is inevitable to charge / discharge using the forecast price. That is, charging is performed when the predicted price is low, and discharge is performed when it is expensive. Therefore, damage may occur due to the difference between the forecast price and the actual settlement price. For example, if discharge was performed because the expected price at the time of operation was high, but the actual settlement price is lower than when charging is performed, there is a possibility that the charge / discharge operation may be caused by charging at a high price and discharging at a low price. . Similar problems can also occur in peak power consumption and peak load contribution costs. In other words, in the prediction, the maximum power consumption or the maximum grid load did not appear, but the actual operation result. In this case, if the charge / discharge operation is performed using only the predicted value, the maximum power consumption cost and peak that could be reduced by not discharging at the time when the event occurred, even though the SOC reserve power for discharging was obtained. It does not reduce the load contribution cost.

Accordingly, the prediction data correction module 111 corrects the prediction data of the settlement price (or load) by using real-time price information (or real-time load information) in order to reduce the risk of the aforementioned error according to the user's setting. can do. For example, as shown in the upper part of FIG. 5, the prediction data correction module 111 uses the prediction data as it is in charge / discharge schedule generation if there is no real time price information (or real time load information) corresponding to the current time period. However, when there is real time price information or real time load information as shown in FIG. 5, the prediction data correction module 111 may correct the prediction data by the weighted average of the real time price or real time load and their prediction data. The corrected prediction data can be used for the charging and discharging schedule described later. According to the correction of the prediction data, an error between the prediction data and the value used in the actual settlement may be reduced.

In addition, the prediction data correction module 111 may step the prediction data in order to reduce the risk that may occur due to the difference in the minute prediction values that may occur in the optimization-based charging / discharging schedule creation method according to the user's setting. . For example, when the market price forecast value of the current time period is slightly larger than the predicted value of the next time period when charging is required, a schedule for filling in the next time period is created, and thus, charging is not performed in the current time period. However, if the market price rises in the next period, it will be charged at a higher cost than planned. In order to disperse these risks, the prediction data correction module 111 divides the corresponding time period into a plurality of unit time periods as shown at the bottom of FIG. 5, and divides the prediction data for the real-time price or the real-time load by at least one step. It can be staircased by unit time intervals according to the intervals. That is, when the staircase is performed in this example, the price of the current time period and the next time period is corrected to the same value, and thus charging is performed equally between the current time period and the next time period. Therefore, even if the market price increases in the next period, the damages from the price increase can be reduced than if the forecast value is used directly.

As such, the prediction data correction module 111 may perform two functions as described above. That is, the prediction data can be corrected or the staircase interval can be set appropriately in consideration of the characteristics of the microgrid and the power market, which is optional according to the user's setting, that is, one of two functions or two functions. All can be used.

In order to use the energy storage device as an emergency generator, the minimum charge setting module 112 sets a minimum charge amount so that the microgrid load can be supplied for a predetermined time or more (for example, the time required for starting an emergency diesel generator) during independent operation. Do it. That is, when the charging and discharging schedule of the energy charging device ESS is prepared, the energy charging device ESS should be maintained above the minimum charging amount. The minimum charging amount setting module 112 functions to set the minimum charging amount.

If the minimum charging amount is set high, the charge / discharge capacity of the energy storage device ESS may be reduced, thereby reducing the gain obtained by charging or discharging the energy storage device ESS. Therefore, in order to increase the utilization of the energy storage device (ESS), it is necessary to set the minimum charge amount as low as possible.

Accordingly, unlike the existing patents, the minimum charge setting module 112 may differently set the minimum SOC criterion for each time period by using the load and power generation amount prediction value and the minimum time during which the energy storage device (ESS) should operate as an emergency generator. As shown in FIG. 6, when the predicted value of (load-generation) after the time period is large, the energy storage device ESS needs to supply a lot of power in an emergency, and thus sets the minimum charge amount of the time period to be high. In the opposite case, set the minimum charge level low. As a result, the amount of charge corresponding to the hatched area of FIG. 6 can be utilized for normal operation compared to the method used in the related art. This minimum charge amount is calculated as in Equation 1 below.

In Equation 1, SOC _opr ^min (t) represents the minimum charge amount of the energy storage device (ESS) for emergency power generation, SOC _mech ^min (t) represents the minimum charge amount of the physical energy storage device (ESS), t _{min, back} represents the minimum time that the energy storage device (ESS) should operate as an emergency generator, P _LD (x) represents the load prediction value, P _DG (x) represents the generation prediction value (kw), E _{ESS, rated} represents the rated energy capacity of the energy storage device,

The temporary schedule preparing module 113 converts the charge and discharge control problem into an optimization problem and finds an optimal solution of the optimization problem, thereby creating a temporary charge and discharge schedule for the energy storage device (ESS). Specifically, the temporary schedule creation module 113 functions to create a temporary charging and discharging schedule for optimally controlling the energy storage device ESS for each time period. As described above, the operating device 100 according to an embodiment of the present invention generates a schedule such that the sum of the energy fee, the maximum power consumption cost, and the peak charge fee and the life reduction cost of the energy storage device are minimized. In this optimization process, the objective function and the constraints may be expressed as Equations 2 and 3, respectively.

In Equation 2, PESS (i) represents the output of the energy storage device (ESS) in the time interval (i), C _energy represents the energy rate, C _{MG, peak} represents the maximum power consumption rate, C _{market, The peak} represents the peak charge, the C _{wear, the tear} represents the life reduction cost of the energy storage device (ESS), the specific equation can be determined by the electricity bill settlement rules of the power market to which the microgrid belongs.

As the constraints, the upper and lower limits of the active power and the upper and lower limits of the charge amount may be used. In addition, the temporary schedule preparation module 113 may use a charge amount (SOC) constraint, such as Equation 3, in order to secure a discharge reserve force corresponding to the error of the predicted value.

In Equation 3, T _{SOC, max} represents a time period during which the filling amount should be maximum, SOC (T _{SOC, max} ) represents the filling amount in the time period T _{SOC, max} , and SOC _max means the maximum filling amount.

The constraint referred to in Equation 3 may perform the following function. For example, suppose a situation is expected that there will be no discharge gain in the afternoon. In this situation, the conventional technology does not perform charging at low dawn and morning time even if the SOC is low. Therefore, even if a situation in which the actual price rises in the afternoon can benefit from the discharge may occur, the discharge may not be performed due to the lack of the SOC. However, if you apply the preceding constraints to the schedule and set the maximum amount of charge (SOC) time to 8 am, the time before 8 am is maximized until the charge is maximized at 8 am by the operating process of the energy storage device (ESS). Charge / discharge can be performed in the liver. Therefore, even if an unexpected event occurs after 8 o'clock, the discharge can be performed.

The schedule correction module 114 functions to generate a final schedule by correcting the temporary schedule created through the temporary schedule preparation module 113. If the objective function is linear (defined by most of the electrical charges) and there are time intervals with the same coefficient, the combination of optimal solutions that minimizes the objective function can be infinite. That is, there are infinite charge / discharge schedules for minimizing the objective function. For example, if the price of time period 1 and time 2 is the same as 100 won / kWh, charge 10 kWh at hour 1 and charge 5 kWh at hour 2 and charge 5 kWh at hour 2 and charge 10 kWh at time 2 Charging is the same as all costing 1,500 won. As described above, in order to reduce the risk of prediction error, various charging / discharging schedules of minimizing the objective function in the present invention have the same charging periods (discharge prices are opposite signs) among the schedules derived from the optimization problem as shown in FIG. The schedule for distributing the charge / discharge as much as possible can be selected as the final charge / discharge schedule.

The schedule correction method performed through the schedule correction module 114 may be largely divided into three processes.

First, the schedule correction module 114 may define the charging price and the maximum charging amount of each time period. The temporary schedule created through the temporary schedule creation module 113 may be substituted into the objective function of the optimization problem to find the price coefficient activated in the individual time zone and calculate the charge price of the individual time period. Next, calculate the maximum charge amount that does not change the charge price for each time period. For example, charging a new energy storage device (ESS) generates a new maximum power consumption of the microgrid, which increases the maximum power consumption rate. Therefore, in this case, the maximum charge amount of each time period is the maximum charge amount that can maintain the power consumption of each time period below the maximum power consumption prediction value (the larger of the maximum power consumption generated by applying the existing maximum power consumption and schedule). Is determined

In addition, the schedule correction module 114 may derive a set of time periods for performing a correction operation based on the time period T currently undergoing the calculation. That is, the schedule correction module 114 derives a set of time periods that remain in the same state, that is, a set of correction time periods, in consideration of the state of charge or discharge of the time period T currently being calculated. Do it. For example, if the schedule result of the time period T in which the current operation is performed is charging, the set of correction target time periods is equal to the current operation time period and the charging price among the time periods after the current operation time period and immediately before the scheduled time period. It is the same set of time periods. On the contrary, if the schedule result of the time period T in which the current calculation proceeds is discharged, the set of time periods to be corrected is one of the time periods that have the same charging price as the current calculation time period, among the time periods after the current calculation time period and before charging is scheduled. Represents a set of. If the schedule result of the current operation time period is 0, the set of time targets to be corrected is defined based on the schedule result of the first time when the schedule result after the current operation time period is not 0.

In addition, when the derivation of the correction target time period set to perform the above-described correction operation is completed, the schedule correction module 114 performs a schedule correction operation on time periods belonging to the correction target time period set. First, the schedule correction module 114 calculates an average output of time periods belonging to the set of time periods to be corrected, and performs schedule correction for time periods in the order of the maximum charge amount mentioned above among the time periods belonging to the time period set to be corrected. You can proceed. If the maximum charge amount of the corresponding time period is smaller than the average output, the schedule of the corresponding time period may be set as the maximum charge amount, the average power of the remaining time periods may be recalculated, and the operation for the next time period may be performed. On the contrary, if the maximum charging amount is larger than the average charging amount, the charging amount of the corresponding section is set as the average charging amount and the operation for the next section is performed.

The command value deriving unit 120 sets an operation mode (manual / scheduling) of the energy storage device ESS according to a charging and discharging schedule, that is, a final charging and discharging schedule created through the schedule preparing unit 110, and sets the set validity. According to the power output command value, the function of deriving the state and the active power command value of the energy storage device (ESS) to be delivered to the controller 130 of the energy storage device (ESS). If the operation mode of the energy storage device ESS is the manual mode, there is no change of the state command value of the energy storage device ESS, and only the active power command value is changed to the user input value. However, when the energy storage device ESS is operated in the schedule mode, the state and output command value of the energy storage device ESS may be determined. In addition, the command value deriving unit 120 changes the state of the energy storage device ESS to ready (semiconductor switch off) when the schedule result command value is 0. This operation can reduce the loss caused by unnecessary standby operation (switching of the semiconductor switch to control to zero as an output).

The controller 140 performs an operation state and an output control of the energy storage device ESS based on the command value derived from the command value deriving unit 120 and transmitted to the microgrid operating system, and an operation state setting value. Do it. As described above, the operation state of the energy storage device (ESS) may be divided into a manual operation mode and a schedule operation mode used during grid linkage operation, and a constant voltage / frequency operation mode and synchronization operation mode used during independent operation. .

Here, the schedule operation mode, that is, the active power and reactive power control mode indicates a mode for controlling the active power and the reactive power according to the command value, and the constant voltage / frequency operation mode indicates a mode for controlling the voltage and frequency as the command value. . The synchronous operation mode represents a mode in which the magnitude and phase angle of the voltage of the secondary side (microlog grid) of the microgrid associated switch are synchronized with the voltage of the primary side by controlling the magnitude and phase angle of the output voltage.

In addition, the controller 140 provides protection functions such as AC / DC voltage, current, and charge amount to protect the system of the energy storage device (ESS). A characteristic of the controller 140 is that an uninterruptible operation is possible. In other words, if the anti-island function is turned off, an autonomous operation (voltage / frequency control mode) is automatically performed when an accident in the power grid is detected. It also detects when the upper grid is restored and synchronizes automatically. When the microgrid link is closed, it automatically switches to the active / reactive power mode. In this manner, when the energy storage device (ESS) maintains the synchronization mode after being connected to the upper power grid, problems that may occur due to measurement error and delay (ESS overcurrent protection operation, excessive inrush current, etc.) may be minimized.

The user interface 130 provides an environment in which a user expresses various information for determining various matters related to the operation of the energy storage device (ESS) and controls related devices. Data expressed in the user interface 130 is as follows.

-Energy storage device (ESS): status (stop / ready / operation), operation mode (independent operation / synchronization / auto / manual), warning and alarm, charge level (SOC), active / reactive power output, voltage, frequency, communication Status, higher grid synchronization results, etc.

-Microgrid switch: open / close, active / reactive power, communication status, etc.

-Charge / discharge schedule of energy storage device (ESS): schedule result and operation history, market price history and forecast value, microgrid power consumption history and forecast value, upper grid load history and forecast value, operation gain of energy storage device (ESS), etc.

The user may perform the following operations through the user interface unit 130 based on the above materials.

-Energy storage device (ESS): control status (stop / ready / operation), anti-island function setting, automatic / manual mode selection, control of active / reactive power output in manual mode, energy storage device (ESS) in independent operation Output voltage control etc.

-Microgrid switch: open / close control, etc.

-Charge / discharge schedule of energy storage device (ESS): change of schedule creation cycle, change of variables related to schedule creation, etc.

In addition, the user interface unit 130 may further provide two functions to prevent a problem that may occur due to an incorrect operation by the user. Here, first, the user interface 130 may provide a higher power grid-linked black start prevention function. Here, when the anti-island mode is activated and a power failure occurs due to a failure of the upper power grid, the energy storage device ESS stops operating. In order to supply power to the microgrid by using the energy storage device (ESS) as an emergency power source, the user must open the microgrid link switch and start the energy storage device (ESS). If the energy storage device (ESS) is activated without opening the microgrid associated switch, in the worst case, an overcurrent may occur in the energy storage device (ESS), and the semiconductor switch may be damaged. In order to prevent such a problem, in the user interface unit 130, when a power failure occurs (that is, when a power failure signal is detected), when the upper power grid link switch is closed, the user inputs an operation command of the energy storage device (ESS). Even if it can block the operation signal of the energy storage device (ESS) by itself and display a warning message.

In addition, the user interface 130 may provide an asynchronous reassociation prevention function. If the upper grid is restored during stand-alone operation, reconnection to the upper grid of the microgrid must be performed. At this time, if the microgrid link switch is closed while the upper power system and the microgrid are not synchronized (magnitude and phase angle), excessive inrush current may occur. have. Asynchronous reconnection prevention function prevents the operation of the microgrid link switch and displays the relevant warning message if the voltages of the upper grid and the consumer grid are not synchronized during stand-alone operation.

As a result of the demonstration of the operating device 100 according to the embodiment of the present invention described above, the actual operation is possible while minimizing the energy cost, the maximum power consumption fee, the peak load contribution fee, and the life reduction cost of the energy storage device (ESS). The point was confirmed.

8 is a flowchart illustrating an operating method (hereinafter, an operating method) for an energy storage device for a microgrid according to an embodiment of the present invention. Now, a description will be given of an operating method according to an embodiment of the present invention with reference to FIGS. 8 to 12. In addition, the following description will be omitted to omit overlapping with the above-mentioned parts.

In step S110, a schedule preparation unit prepares a schedule for charging and discharging the energy charging device ESS using the microgrid operating system. Specifically, step S110 may include collecting forecast data and real-time operation information on load, power generation, and energy price for each time period from the microgrid operating system, and step S110 may include the steps illustrated in FIG. 9. Can be.

The step S111 is a step of correcting the prediction data of the time period by the schedule preparation unit based on the real-time price information within the time period for each time interval according to the user's setting. In addition, the step S111 may include dividing one time period into a plurality of unit time periods according to a user's setting and stepping the prediction data according to at least one stepping interval for each unit time period. . However, the two processes are not necessarily performed in the correction process and the staircase process of the prediction data, and may be performed selectively or all according to the user's setting.

In step S112, in order to use the energy storage device as an emergency generator, the schedule preparing unit sets a minimum charge amount so that the microgrid load can be supplied for a predetermined time or more (for example, the time required for starting an emergency diesel generator) during independent operation. Step. That is, when the minimum charging amount is set high, the charge / discharge capacity of the energy storage device ESS may be reduced, thereby reducing the gain obtained by charging or discharging the energy storage device ESS. Therefore, in order to increase the utilization of the energy storage device (ESS), it is necessary to set the minimum charge amount as low as possible.

In addition, step S112 may be performed by differently setting the minimum SOC criteria of the individual time periods by using the load and generation amount prediction value and the minimum time that the energy storage device (ESS) should operate as an emergency generator. As described with reference to FIG. 6, if the predicted value of (load-generation) after the corresponding time period is large, the energy storage device ESS needs to supply a lot of power in an emergency, and thus sets the minimum charge amount of the corresponding time period high. In the opposite case, it is desirable to set the minimum charge amount low.

In addition, as described with reference to Equation 1, step S112 may include a minimum charge amount of the energy storage device for emergency power generation, a minimum charge amount of the physical energy storage device, a minimum time that the energy storage device should operate as an emergency generator, and a load. Prediction data for power generation, prediction data for power generation, and rated energy capacity of an energy storage device.

Step S113 is a step of preparing a temporary charging and discharging schedule for the energy storage device by converting a charging and discharging control problem into an optimization problem and finding an optimal solution of the optimization problem. Here, the objective function of the optimization problem can be made such that the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee and the life reduction cost of the energy storage device are minimized. Here, since the objective function and the constraints have been described with reference to Equations 2 and 3 in the optimization process performed through step S113, redundant descriptions are omitted.

Step S114 is a step of generating a final charging and discharging schedule by analyzing the charging price and the temporary charging and discharging schedule for each time period, and distributing the temporary charging and discharging schedule to maximize distribution of the charging and discharging schedule for each time period. . Here, the step of generating the final charge and discharge schedule through the step S114 is shown in FIG.

Step S114a is a step of defining the charge price and the maximum charge amount of the individual time period. Here, the charging price may be calculated by substituting the temporary schedule created in step S113 into the objective function of the optimization problem to find the price coefficient activated in the individual time zones and calculate the charging price of the individual time periods.

In addition, step S114a may define the maximum charge amount does not change the charge price for each time period. For example, charging a new energy storage device (ESS) results in a new maximum power consumption of the microgrid, which increases the maximum power consumption rate. Therefore, in this case, the maximum charge amount of each time period is determined as the maximum charge amount that can maintain the power consumption of each time period below the maximum power consumption estimate value (the greater of the maximum power consumption generated by applying the existing maximum power consumption and schedule). do

Step S114b is a step of initializing the variables used for the correction to be described below, and setting the correction target to the current time period.

Step S114c is a step of determining whether correction for the current time period, that is, the time period T, is completed. As a result of the determination, if it is determined that the correction for the time period T is completed, the control is passed to the step S114f. Otherwise, control passes to a step S114d.

The step S114d is a step of deriving a set of time periods for performing a correction operation based on the time period T currently being calculated. That is, the step S114d functions to derive the set of time periods that remain in the same state, that is, the set of correction target time periods, in consideration of the state of charge or discharge of the time period T currently being calculated. In addition, in operation S114d, when the schedule result of the current operation time period is 0, the set of correction target time periods may be defined based on the schedule result of the first time when the schedule result after the current operation time period is not zero.

In step S114e, when the derivation of the set of time target sections is corrected, a schedule correction operation is performed on time periods belonging to the set of time target sections. Here, in step S114e, the average output of the time periods belonging to the set of time periods to be corrected may be calculated, and the schedule correction may be performed for the time periods in the order in which the maximum charge amount mentioned above is small among the time periods belonging to the time period set to be corrected. If the maximum charge amount of the corresponding time period is smaller than the average output, the schedule of the corresponding time period may be set as the maximum charge amount, the average power of the remaining time periods may be recalculated, and the operation for the next time period may be performed. On the contrary, if the maximum charging amount is larger than the average charging amount, the charging amount of the corresponding section is set as the average charging amount and the operation for the next section is performed.

Step S114f is a step of determining whether the current time period is the last time period, that is, whether there is a subsequent time period that requires correction. Here, when there is a time period that needs to be corrected, control is transferred to step S114g to select a next time period. Otherwise, control passes to step S120.

In this way, the charging and discharging schedule of the energy storage device may be prepared for each time interval to minimize the operating cost of the microgrid through the step S110. In addition, the step S110 is made to minimize the sum of the energy bill, the maximum power consumption cost, the peak load contribution fee and the cost of reducing the life of the energy storage device, thereby lowering the customer's electricity bill compared to the prior art and more efficient operation is possible. There is an advantage. In addition, the step S110 performs error correction on the prediction data considering the real-time price, thereby minimizing the damage caused by the error.

In step S120, the command value deriving unit determines the operation state of the energy storage device according to the user setting information and the charging and discharging schedule, and derives an effective power command value to be output from the energy storage device. Here, step S120 may be performed by performing the steps illustrated in FIG. 11. As explained earlier. When the operation mode of the energy storage device ESS is the manual mode, there is no change of the state command value of the energy storage device ESS, and only the active power command value may be changed to a user input value. In addition, as shown in step S122, when the schedule result command value is 0, control is transferred to step S123 to change the state of the energy storage device to a ready state (ie, semiconductor switching off). This operation can reduce the losses caused by unnecessary standby operations.

In step S130, the controller controls the operation of the energy storage device according to the operating state and the effective power command value. Specifically, step S130 is a step of performing the operation state and output control of the energy storage device (ESS) on the basis of the command value and the operation state set value derived through the step S120 to the microgrid operating system. Here, the control step made through the step S130 may provide protection functions such as AC / DC voltage and current, SOC, etc. to protect the own system of the energy storage device ESS as shown in FIG. You can switch modes. In this manner, when the ESS maintains the synchronization mode after being connected to the upper power grid, problems that may occur due to measurement error and delay (ESS overcurrent protection operation, excessive inrush current, etc.) can be minimized.

In addition, according to the operating method according to an embodiment of the present invention, when a power failure generation signal is sensed by the user interface unit and the upper power grid link switch is closed, when the operation command of the energy storage device is input from the user, The method may further include blocking an operation signal of the energy storage device according to the operation command and generating a warning message. The method may further include, by the user interface unit, interrupting an operation of the link switch of the microgrid and generating a warning message when the voltages of the upper power grid and the consumer power grid are not synchronized during the independent operation of the energy storage device. can do.

As described above, the best embodiment has been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (20)

1. Collect forecast data and real-time operating information about load, power generation and energy prices from time to time, from the microgrid operating system, define the minimum amount of energy storage connected to the microgrid by time, and minimize the operating costs of the microgrid. A schedule preparation unit to prepare a charge and discharge schedule of the energy storage device for each time interval as possible;

   A command value deriving unit which determines an operating state of the energy storage device and derives an effective power command value to be output from the energy storage device according to user setting information and the charge and discharge schedule; And

   And a controller configured to control an operation of the energy storage device according to the operation state and an active power command value.

   The schedule preparation unit is an operating device for the energy storage device for a microgrid, characterized in that the charging and discharging schedule to minimize the sum of the energy charge, maximum power consumption cost, peak load contribution fee and the cost of reducing the life of the energy storage device .
2. The method of claim 1,

   The schedule preparation unit may further include a prediction data correction module for correcting the prediction data of the time period based on real-time price information within the time period for each time period according to a user's setting. Operating device for.
3. The method of claim 2,

   The prediction data correction module may classify one time period into a plurality of unit time periods according to the user's setting, and micronize the prediction data according to at least one stepping interval for each unit time period. Operating device for energy storage for grid.
4. The method of claim 1,

   The schedule preparation unit includes a minimum charge setting module for setting a minimum charge amount of the energy storage device connected to the micro grid for each time period, and the minimum charge amount setting module includes a minimum charge amount of the energy storage device for emergency power generation and physical energy storage. Based on the minimum charge of the device, the minimum time the energy storage device should operate as an emergency generator, the forecast data for the load, the forecast data for the generation and the rated energy capacity of the energy storage device, Operating device for an energy storage device for a microgrid, characterized in that the setting.
5. The method of claim 1,

   The schedule preparation unit converts the charging and discharging control problem into an optimization problem, and finds an optimal solution of the optimization problem, thereby operating the energy storage device for the microgrid, wherein a temporary charging and discharging schedule is created for the energy storage device. Device.
6. The method of claim 5,

   The objective function of the optimization problem is the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee, and the reduced lifespan cost of the energy storage device.
7. The method of claim 6,

   The schedule preparation unit

   A schedule correction module is further configured to analyze charge prices by time periods and the temporary charge and discharge schedules, and generate a final charge and discharge schedule by distributing the temporary charge and discharge schedules to maximize distribution of charge and discharge plans by time periods. An operating device for an energy storage device for a microgrid, comprising.
8. The method of claim 7, wherein

   The schedule preparation unit defines charge prices and maximum charge amounts of individual time periods, and defines time periods that are continuously in the same state as a charging state or a discharge state as a set of correction target time periods, and compares the time periods belonging to each correction target time period set. An operation device for an energy storage device for microgrids, the final charge and discharge schedules are generated by calculating the average power and performing a calibration by comparing the average power with time periods belonging to each set of time periods to be corrected.
9. The method of claim 1,

   The user interface unit may further include a user interface unit used to generate the user setting information. When the power failure generation signal is detected and the upper power grid link switch is closed, an operation command of the energy storage device is input from the user. And an operation signal of the energy storage device according to the operation command, and generating a warning message.
10. The method of claim 9,

    The user interface unit blocks the operation of the microgrid associated switch and generates a warning message when the voltages of the upper power grid and the consumer power grid are not synchronized during the independent operation of the energy storage device, and generates a warning message. Operating device for storage.
11. Collecting, by the scheduler, prediction data and real-time operation information on load, power generation, and energy price for each time period from the microgrid operating system;

    Defining, by the schedule preparation unit, a minimum charge amount of the energy storage device connected to the microgrid for each time period;

    Creating, by the schedule preparation unit, a charging and discharging schedule of the energy storage device for each time interval such that an operating cost of the microgrid is minimized;

    Determining, by the command value deriving unit, an operating state of the energy storage device according to user setting information and the charging and discharging schedule, and deriving an effective power command value to be output from the energy storage device; And

    Controlling, by a control unit, an operation of the energy storage device according to the operation state and an active power command value;

    The charging and discharging schedule of the energy storage device may be prepared by minimizing a sum of an energy fee, a maximum power consumption cost, a peak load contribution fee, and a reduction in the lifespan cost of the energy storage device. How to operate.
12. The method of claim 11,

    And correcting the prediction data of the time period by the schedule preparation unit based on real time price information within the time period for each time period according to a user's setting. How to operate.
13. The method of claim 12,

    The correcting of the prediction data of the time period may include: dividing one time period into a plurality of unit time periods according to a setting of the user; And

    And stairizing the predicted data according to at least one stepping interval for each unit of time periods.
14. The method of claim 11,

    Defining the minimum charge amount of the energy storage device,

    The minimum charge of the energy storage device for emergency power generation, the minimum charge of the physical energy storage device, the minimum time that the energy storage device should operate as an emergency generator, the predictive data for the load, the prediction data for the power generation and the energy storage device An operating method for an energy storage device for a microgrid, characterized in that it is based on a rated energy capacity.
15. The method of claim 11,

    The step of preparing a charge and discharge schedule of the energy storage device may include creating a temporary charge and discharge schedule for the energy storage device by converting a charge and discharge control problem into an optimization problem and finding an optimal solution of the optimization problem. An operating method for an energy storage device for a microgrid, comprising.
16. The method of claim 15,

    The objective function of the optimization problem is a method for operating an energy storage device for a microgrid, characterized in that the sum of the energy charge, the maximum power consumption cost, the peak load contribution fee, and the life reduction cost of the energy storage device are minimized.
17. The method of claim 16,

    Creating a charge and discharge schedule of the energy storage device,

    Analyzing the charge price by time period and the temporary charge and discharge schedule, and generating a final charge and discharge schedule by distributing the temporary charge and discharge schedule such that the charge and discharge schedule by time period is maximally distributed. An operating method for an energy storage device for a microgrid.
18. The method of claim 17,

    The generating of the final charge and discharge schedules may define charge prices and maximum charge amounts of individual time periods, and define time periods that are continuously in the same state as a charged state or a discharge state as a set of correction target time periods, and each correction target time period. A method for operating an energy storage device for a microgrid, comprising calculating a mean output of time periods belonging to an interval set, and performing a correction by comparing an average power with time periods included in each time interval set.
19. The method of claim 11,

    If an operation command of the energy storage device is input by the user when the power failure generation signal is detected by the user interface unit and the upper power grid link switch is closed, the operation signal of the energy storage device according to the operation command is cut off, And generating a warning message.
20. The method of claim 19,

    By the user interface unit, during the independent operation of the energy storage device, when the voltage of the upper power grid and the consumer power grid is not synchronized, the operation of the microgrid linked switch, further comprising the step of generating a warning message further comprising: An operating method for an energy storage device for a microgrid.

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