KR20230019892A - System for controlling output fluctuation of electric power, energe storage system and method - Google Patents

Abstract

An output fluctuation control system which controls output fluctuations of power generated from renewable power plants comprises: a generated power monitoring unit which monitors power generated from renewable power plants and the remaining energy of an energy storage system (ESS); a fluctuation rate limit setting unit which sets a fluctuation rate limit value of transmission power transmitted to a power system based on the remaining energy of the energy storage system; a charging and discharging amount determination unit which determines the charging and discharging amount of the energy storage system based on the set fluctuation rate limit value; and an output fluctuation control unit which controls the output fluctuation of power by controlling the charging and discharging of the energy storage system according to the determined charging and discharging amount.

Description

System, energy storage device and method for controlling the output fluctuation of power generated in a renewable power plant

The present invention relates to a system, an energy storage device, and a method for controlling output fluctuations of power generated in a renewable power plant.

Power generated from new and renewable power plants (eg, wind power plants, solar power plants, etc.) has many output fluctuations depending on weather conditions, topographical characteristics, and time. In addition, when power with output fluctuations is transmitted to the power system as it is, power quality problems such as voltage fluctuations, frequency fluctuations, and stability deterioration may occur, and these problems may greatly affect the stable operation of the power system.

Accordingly, the need to stably transmit power generated from renewable power plants to power systems is emerging worldwide, and preliminary research is under way to apply legal regulations on output fluctuations.

For example, there is an attempt to limit transmission power fluctuations to a new and renewable power plant system with a certain regulatory value according to each country or power system operator, and control of an energy storage device for stabilizing output to a conventional power system. Methods include a normal ramp rate (NRR) control method, a continuous moving average (CMA) control method, and a discrete moving average (DMA) control method.

In addition, the evaluation method of the output fluctuation rate of the renewable power plant includes a fluctuation rate evaluation method for the average value of the synthesized output, a fluctuation rate evaluation method for the difference between the maximum and minimum values, a fluctuation rate evaluation method for the difference between the initial value and the final value of 1 minute, etc. there is

However, if the energy storage device is controlled to stabilize the output of renewable generation without separate management of the remaining energy of the energy storage device, the energy storage device operates biasedly toward charging or discharging according to the daily output pattern of renewable generation, resulting in overcharging. Otherwise, continuous operation may be impossible due to excessive discharge.

Korean Patent Publication No. 2017-0002311, which is a prior art, discloses a configuration for setting an energy charge/discharge control mode of an energy storage device based on system scheduling based on a power variation rate system and user scheduling reflecting user input.

In order to solve the above problem caused by regulating the output fluctuation rate of power to a constant value, the fluctuation rate limit value of the transmission power transmitted to the power system is set based on the remaining energy of the energy storage device within the regulation value, and the set fluctuation rate limit value It is intended to control the output variation of power generated from a renewable power plant by controlling the charging and discharging of the energy storage device according to the charge and discharge amount of the energy storage device determined based on the energy storage device. However, the technical problem to be achieved by the present embodiment is not limited to the technical problems described above, and other technical problems may exist.

As a technical means for achieving the above-described technical problem, an output fluctuation control system for controlling an output fluctuation of power generated in a new and renewable power plant according to a first aspect of the present invention is a power and energy storage device generated in the renewable power plant (ESS, Energy Storage System) generated power monitoring unit for monitoring the remaining energy; a fluctuation rate limiting value setting unit for setting a fluctuation rate limiting value of transmission power transmitted to the power system based on the remaining energy of the energy storage device; a charge/discharge amount determiner configured to determine a charge/discharge amount of the energy storage device based on the set variation rate limit value; and an output variation control unit configured to control the output variation of the power by controlling the charging and discharging of the energy storage device according to the determined charge/discharge amount.

An energy storage system (ESS) according to a second aspect of the present invention is an output variation control system that controls the output variation of power generated in a new and renewable power plant by monitoring the remaining energy amount for each predetermined unit time, and the remaining energy amount Residual energy transmission unit for transmitting the; a charge/discharge amount receiver configured to receive a charge/discharge amount from the output variation control system for each predetermined unit time; And a charging and discharging unit for controlling the output fluctuation of the power generated in the renewable power plant by charging and discharging according to the received charge and discharge amount, wherein the charge and discharge amount is determined based on a limit value of the fluctuation rate of the transmitted power transmitted to the power system, , The fluctuation rate limit value may be set based on the remaining energy amount of the energy storage device.

A method for controlling the output fluctuation of power generated in a renewable power plant performed by an output fluctuation control system according to a third aspect of the present invention is the power and energy storage system (ESS, Energy Storage System) generated in the renewable power plant. monitoring residual energy; setting a limit value for a variation rate of transmission power transmitted to a power system based on a residual amount of energy of the energy storage device; determining a charge/discharge amount of the energy storage device based on the set variation rate limit value; and controlling the output variation of the power by controlling the charging and discharging of the energy storage device according to the determined charging and discharging amount.

The above-described means for solving the problems is only illustrative and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and detailed description.

According to any one of the above-described problem solving means of the present invention, a fluctuation rate limit value of the transmission power transmitted to the power system is set based on the remaining energy amount of the energy storage device, and the charge/discharge amount of the energy storage device is determined based on the set fluctuation rate limit value. Since the charging and discharging of the energy storage device is controlled according to the method, it is possible to stably supply power to the power system while meeting the fluctuation rate regulation.

In addition, since the output variation of the power generated by the new and renewable power plant is controlled, it is possible to satisfy the grid connection regulation of the new and renewable power plant.

In addition, since the final charge and discharge of the energy storage device is determined based on the remaining energy amount of the energy storage device, biased charging and discharging of the battery can be prevented, and continuous operation of the energy storage device and power prices by time or various subsidies are considered. Profits can be increased by strategically adjusting the charge/discharge amount of energy storage devices.

1 is a block diagram of an output variation control system according to an embodiment of the present invention.
2 is a block diagram of an output variation control device shown in FIG. 1 according to an embodiment of the present invention.
3 is a block diagram of the energy storage device shown in FIG. 1 according to an embodiment of the present invention.
4A to 4B are diagrams for explaining a method of adjusting a control coefficient of a proportional controller and a method of setting a limiting value for a rate of change according to an embodiment of the present invention.
5 is a flowchart illustrating a method of controlling an output variation of power generated in a renewable power plant according to an embodiment of the present invention.
6 is a flowchart illustrating a method of controlling output fluctuations of power generated in a renewable power plant according to another embodiment of the present invention.
7 is a flowchart illustrating a method of controlling an output variation of power generated in a renewable power plant according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention with reference to the accompanying drawings. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected" but also the case where it is "electrically connected" with another element interposed therebetween. . In addition, when a certain component is said to "include", this means that it may further include other components without excluding other components unless otherwise stated.

In this specification, a "unit" includes a unit realized by hardware, a unit realized by software, and a unit realized using both. Further, one unit may be realized using two or more hardware, and two or more units may be realized by one hardware.

In this specification, some of the operations or functions described as being performed by a terminal or device may be performed instead by a server connected to the terminal or device. Likewise, some of the operations or functions described as being performed by the server may also be performed in a terminal or device connected to the corresponding server.

Hereinafter, specific details for the implementation of the present invention will be described with reference to the accompanying configuration diagram or process flow chart.

1 is a block diagram of an output variation control system according to an embodiment of the present invention.

Referring to FIG. 1 , the power variation control system may include an output variation control device 100 , a renewable power plant 110 and an energy storage device 120 . However, since the output variation control system of FIG. 1 is only one embodiment of the present invention, the present invention is not limitedly interpreted through FIG. 1, and may be configured differently from FIG. 1 according to various embodiments of the present invention. .

The output variation control device 100 may monitor the power generation state of the renewable power plant 110 by receiving the amount of power generated by the renewable power plant 110 from the renewable power plant 110 for each predetermined unit time.

The output variation control device 100 may receive the remaining energy amount of the energy storage device 120 from the energy storage device 120 for each predetermined unit time and monitor the change in the remaining energy amount.

The output variation control device 100 sets a variation rate limit value of the transmission power transmitted to the power system based on the remaining energy of the energy storage device 120, and determines the charge/discharge amount of the energy storage device 120 based on the set variation rate limit value. can decide

The output variation control device 100 may control the output variation of power generated from the renewable power plant 110 by controlling the charging and discharging of the energy storage device 120 according to the determined charging and discharging amount.

Renewable power plant 110 may generate power using an energy source. The renewable power plant 110 may include all power generation systems that generate electricity using renewable energy such as solar heat and geothermal heat.

Transmission power transmitted to the power system may vary according to the charge/discharge amount determined by the output variation control device 100 .

The energy storage device 120 may receive information about the charge/discharge amount from the power variation control device 100 for each predetermined unit time. The energy storage device 120 may charge/discharge power according to information about the charge/discharge amount received for each predetermined unit time.

In general, each component of the output variation control system of FIG. 1 is connected through a network (not shown). A network refers to a connection structure capable of exchanging information between nodes such as terminals and servers, such as a local area network (LAN), a wide area network (WAN), and the Internet (WWW: World Wide Web), wired and wireless data communication network, telephone network, and wired and wireless television communication network. Examples of wireless data communication networks include 3G, 4G, 5G, 3rd Generation Partnership Project (3GPP), Long Term Evolution (LTE), World Interoperability for Microwave Access (WIMAX), Wi-Fi, Bluetooth communication, infrared communication, ultrasonic communication, visible light communication (VLC: Visible Light Communication), LiFi, and the like, but are not limited thereto.

Hereinafter, the operation of each component of the output variation control system of FIG. 1 will be described in more detail.

FIG. 2 is a block diagram of an output variation control device 100 shown in FIG. 1 according to an embodiment of the present invention.

Referring to FIG. 2 , the output variation control device 100 may include a generated power monitoring unit 200, a variation rate limit value setting unit 210, a charge/discharge amount determination unit 220, and an output variation control unit 230. Here, the variation rate limiting value setting unit 210 may include a proportional controller 212, a target remaining energy setting unit 214, and a control coefficient adjusting unit 216. However, the output variation control device 100 shown in FIG. 2 is only one implementation example of the present invention, and various modifications are possible based on the components shown in FIG. 2 .

The generated power monitoring unit 200 may monitor power generated from the renewable power plant 110 and residual energy of the energy storage device 120 . For example, the generated power monitoring unit 200 collects the amount of power generated for each preset unit time from the renewable power plant 110, and the energy storage device according to charging and discharging of the energy storage device 120 for each preset unit time. The remaining energy of 120 may be collected from the energy storage device 120 . For example, the preset unit time may be 1 second, 2 seconds, 3 seconds, etc., but is not limited thereto.

The variation rate limit value setting unit 210 may set the variation rate limit value based on the remaining energy of the energy storage device 120 . For example, the variation rate limiting value setting unit 210 may change the variation rate limiting value of the transmission power transmitted to the electric power system for each preset unit of time or for each separately set unit of time.

The variation rate limit value setting unit 210 uses the proportional controller 212 to set the variation rate limit value between the first variation rate and the second variation rate so that the variation rate limit value of the transmitted power is proportional to the energy remaining amount of the energy storage device 120. For example, the first rate of change may be 1% and the second rate of change may be 10%. In this case, the first rate of change is the minimum rate of change, and the second rate of change is the maximum rate of change that cannot exceed the preset rate of change regulation value. However, the final rate of change cannot exceed the rate of change limit.

For example, the fluctuation rate limiting value setting unit 210 may adjust the fluctuation rate limiting value to converge to the second rate of change as the energy remaining amount of the energy storage device 120 approaches a preset maximum charging capacity, As the charging capacity of the lowest value is approached, the variation rate limit value may be adjusted to converge to the first variation rate.

The target residual energy setting unit 214 may set a target residual energy amount of the energy storage device 120 based on the hourly unit price of power.

For example, the target energy remaining amount setting unit 214 sets the target energy remaining amount of the energy storage device 120 in the case of a time period when the unit price of electricity is low (eg, 10:00 to 16:00 in the case of a photovoltaic power plant). It can be set high as the target energy remaining amount. In this case, the energy storage device 120 may store power generated from the renewable power plant 110 up to the first target energy remaining amount during a time period when the unit cost of power generation is low. In contrast, the target energy remaining amount setting unit 214 determines the remaining target energy amount of the energy storage device 120 in the case of a time zone where the unit price of electricity is high (eg, time other than 10:00 to 16:00 in the case of a solar power plant). It may be set as a second target energy residual lower than the first target energy residual.

For another example, the energy storage device 120 may set a weight for the amount of transmitted power according to the generation cost. The target energy residual amount setting unit 214 sets a weight for the amount of transmitted power as a first weight in the time zone when the unit price of electricity is low, and sets a weight for the amount of transmitted power in the time zone where the unit price of electricity is high. It may be set to a second weight lower than the first weight.

In this way, by setting a target energy remaining amount of the energy storage device 120 based on the hourly unit price of electricity or setting a different weight for the amount of transmitted power, the remaining energy amount is increased during a time when the hourly unit price is low, and the hourly unit price is reduced. At high times, you can earn a lot of money by discharging energy.

The control coefficient controller 216 may adjust the control coefficient of the proportional controller 212 when the remaining energy of the energy storage device 120 reaches the target remaining energy. For a moment, a method of adjusting the control coefficient of the proportional controller 212 and a method of setting a limiting value for the rate of change will be described with reference to FIGS. 4A and 4B.

In FIGS. 4A and 4B , reference numeral (a) is a diagram showing a graph of the variation rate limit value when the energy storage device 120 is charging, and reference numeral (b) is a diagram showing a graph when the energy storage device 120 is discharging. It is a diagram showing a graph of the variation rate limit value, and reference numeral (c) is a diagram showing numerical values for the remaining energy of the energy storage device 120 .

Referring to FIG. 4A , when the energy storage device 120 is charged and discharged in a first time interval 407, the variation rate limit value setting unit 210 determines the variation rate of the transmission power according to the first control coefficient of the proportional controller 212. The limit value may be linearly proportionally controlled between the first rate of change 403 and the second rate of change 405 .

When the energy storage device 120 is charged and discharged in the second time period 409, the variation rate limit value setting unit 210 sets the variation rate limit value of the transmitted power according to the second control coefficient of the proportional controller 212 to a first variation rate ( 403) and the second rate of change 405 can be linearly proportionally controlled.

The control coefficient adjusting unit 216 converts the control coefficient of the proportional controller 212 into a first control coefficient in the first time period 407 when the remaining energy amount of the energy storage device 120 is less than the remaining target energy amount 401 . can be set

The control coefficient adjusting unit 216 converts the control coefficient of the proportional controller 212 into a second control coefficient in the second time period 409 in which the remaining energy amount of the energy storage device 120 exceeds the remaining target energy amount 401 . can be set

Here, the slope 413 for proportional control according to the second control coefficient may be set higher than the slope 411 for proportional control according to the first control coefficient. In other words, in the second time interval 409, the change in the rate of change limit value proportionally controlled according to the second control coefficient of the proportional controller 212 is proportional to the first control coefficient of the proportional controller 212 in the first time interval 407. It means that it is greater than the variation of the variation rate limit value that is proportionally controlled according to the

In this way, by setting the control coefficient of the proportional controller 212 differently in consideration of the target energy remaining amount 401 of the energy storage device 120, overdischarge of the energy storage device 120 in the first time interval 407 is prevented. and overcharging of the energy storage device 120 in the second time period 409 can be prevented.

In addition, by setting the slope 413 for proportional control to be high in the second time period 409, the energy storage device 120 can continuously retain energy corresponding to the remaining target energy amount.

As described in FIG. 4A, in the case of controlling the fluctuation limit value by varying the slope of the proportional control based on the target energy remaining amount, a certain amount of power output fluctuation must be allowed, which causes a problem in that a steady state error occurs. .

The problem of occurrence of the steady-state error can be solved by fixing the fluctuation rate limit value based on the target energy remaining amount in proportional control of the fluctuation rate limit value.

Referring to FIG. 4B , as shown in reference numeral (a), when the energy storage device 120 is being charged, the variation rate limit value setting unit 210 sets the remaining energy amount of the energy storage device 120 to the remaining target energy amount 401. In the first time interval 407 that is not reached, the variation rate limit value is linearly proportionally controlled between the first variation rate 403 and the second variation rate 405, and the energy remaining amount of the energy storage device 120 is the target remaining energy amount 401 ), the change rate limit value may be fixed to the second change rate 405 in the second time interval 409 exceeding .

As shown in reference numeral (b), when the energy storage device 120 is discharged, the variation rate limit value setting unit 210 determines the first time period in which the remaining energy of the energy storage device 120 is less than the remaining target energy amount 401. In step 407, the fluctuation rate limit value is fixed to the second rate of change 405, and in the second time period 409 in which the remaining energy amount of the energy storage device 120 exceeds the target remaining energy amount 401, the fluctuation rate limit value is set. Linear proportional control can be performed between the first rate of change 403 and the second rate of change 409 . Returning to FIG. 2 , the charge/discharge amount determiner 220 may determine the charge/discharge amount of the energy storage device 120 based on the set variation rate limit value for each preset unit time.

The output variation control unit 230 may control the output variation of power by controlling the charging and discharging of the energy storage device 120 according to the determined charging and discharging amount.

The output variation control unit 230 may transmit the determined charge/discharge amount to the energy storage device 120 for each predetermined unit time. Also, the output variation controller 230 may command the energy storage device 120 to charge/discharge based on the determined charge/discharge amount.

In this way, since the present invention controls the output variation of the power generated from the renewable power plant according to the remaining energy amount, it is possible to constantly hold the energy corresponding to the target energy remaining amount of the energy storage device, and to reduce the output fluctuation rate of the existing power. It is possible to solve the problem of overdischarge or overcharge of the energy storage device that occurs when it is fixed at a constant value.

On the other hand, those skilled in the art, the generated power monitoring unit 200, the fluctuation rate limit value setting unit 210, the proportional controller 212, the remaining target energy setting unit 214, the control coefficient adjusting unit 216, the charge/discharge amount determining unit 220 ) and the output variation controller 230 may be separately implemented, or one or more of them may be integrated and implemented.

FIG. 3 is a block diagram of the energy storage device 120 shown in FIG. 1 according to one embodiment of the present invention.

Referring to FIG. 3 , the energy storage device 120 may include a residual energy amount transmission unit 300 , a charge/discharge amount receiver 310 and a charge/discharge unit 320 . However, the energy storage device 120 shown in FIG. 3 is only one implementation example of the present invention, and various modifications are possible based on the components shown in FIG. 3 .

The residual energy transmission unit 300 may monitor the residual energy amount for each predetermined unit time and transmit the monitored energy residual amount to the output variation control device 100 that controls the output variation of the power generated from the renewable power plant 110. there is.

For example, the residual energy transmission unit 300 distinguishes the residual energy amount when the energy storage device 120 is being discharged and the remaining energy amount when the energy storage device 120 is being charged, and transmits the information to the output variation control device 100. can transmit

The charge/discharge amount receiving unit 310 may receive information about the charge/discharge amount from the output variation control device 100 for each predetermined unit time. Here, the charge/discharge amount is determined based on the variation rate limit value of the transmission power transmitted to the power system, and the variation rate limit value may be set based on the energy remaining amount of the energy storage device 120 . At this time, the variation rate limit value may be proportionally controlled between the first variation rate and the second variation rate according to the remaining energy by the proportional controller 212 of the output variation control device 100 . For example, the first rate of change may be 1%, and the second rate of change may be a preset value of 10%.

Here, a control coefficient of the proportional controller 212 in a first time period in which the residual energy of the energy storage device 120 is less than the residual target energy amount and the residual energy amount of the energy storage device 120 exceeds the residual target energy amount The control coefficient of the proportional controller 212 in the 2-time period may be set differently.

For example, the control coefficient of the proportional controller 212 that controls the limiting value of the rate of change in the first time interval may be set smaller than the control coefficient of the proportional controller 212 that controls the limiting value of the rate of change in the second time interval. Accordingly, the rate-of-change limit value in the first time interval may be proportionally controlled with a gentler slope than the rate-of-change limit value in the second time interval.

As another example, when the energy storage device 120 is being charged, the limiting value of the rate of change in the first time interval is linearly proportionally controlled between the first rate of change and the second rate of change, and the limiting value of the rate of change in the second time interval is the second rate of change. can be fixed with When the energy storage device 120 is being discharged, the limiting value of the rate of change in the first time period is fixed to the second rate of change, and the limiting value of the rate of change in the second time period is linearly proportionally controlled between the first rate of change and the second rate of change. can

The charging/discharging unit 320 may control the output variation of power generated from the renewable power plant 110 by charging/discharging according to the received charging/discharging amount. For example, the charging/discharging unit 320 increases the output of power generated from the renewable power plant 110 to a certain percentage of the charge amount according to the received charge/discharge amount, stores the power, and supplies the power to the power system up to a certain rate of the discharge amount. It can be controlled to discharge power.

Meanwhile, those skilled in the art will fully understand that each of the residual energy transmission unit 300, the charge/discharge amount receiver 310, and the charge/discharge unit 320 may be separately implemented or one or more of them may be integrated and implemented.

5 is a flowchart illustrating a method of controlling an output variation of power generated in a renewable power plant according to an embodiment of the present invention.

The method for controlling the output variation of power according to the embodiment shown in FIG. 5 is the output variation control device 100 according to the embodiment shown in FIGS. 1 to 4B, the renewable power plant 110, and the energy storage device 120. Steps are processed in time series. Therefore, even if the content is omitted below, the description of the output variation control device 100, the renewable power plant 110, and the energy storage device 120 of FIGS. 1 to 4B is according to the embodiment shown in FIG. It can also be applied to a method for controlling output variation of power.

Referring to FIG. 5 , in step S501, the power variation control device 100 may monitor power generated from the renewable power plant 110 and the remaining energy of the energy storage device 120 for each predetermined unit time.

In step S503 , the output fluctuation control device 100 may set a limit value for the fluctuation rate of the transmission power transmitted to the power system based on the remaining energy amount of the energy storage device 120 .

In step S505, the output variation control device 100 may determine the charge/discharge amount of the energy storage device 120 based on the set variation rate limit value.

In step S507, the output variation control device 100 may control the output variation of power by controlling the charging/discharging amount of the energy storage device 120 according to the determined charging/discharging amount.

In the above description, steps S501 to S507 may be further divided into additional steps or combined into fewer steps, depending on the implementation of the present invention. Also, some steps may be omitted if necessary, and the order of steps may be changed.

6 is a flowchart illustrating a method of controlling output fluctuations of power generated in a renewable power plant according to another embodiment of the present invention.

The output variation control method of power according to the embodiment shown in FIG. 6 is in the output variation control device 100, the renewable power plant 110 and the energy storage device 120 according to the embodiment shown in FIGS. 1 to 5 Steps are processed in time series. Therefore, even if the content is omitted below, the description of the output variation control device 100, the renewable power plant 110, and the energy storage device 120 of FIGS. 1 to 5 is according to the embodiment shown in FIG. It can also be applied to a method for controlling output variation of power.

Referring to FIG. 6 , in step S601, the power variation control device 100 may monitor power generated in the renewable power plant 110 and the remaining energy of the energy storage device 120 for each predetermined unit time.

In step S603 , the output variation control device 100 may set a target energy remaining amount of the energy storage device 120 based on the hourly unit price of power generated from the renewable power plant 110 .

In step S605 , the output variation control device 100 may adjust the control coefficient of the proportional controller 212 when the remaining energy amount of the energy storage device 120 reaches the target remaining energy amount.

In step S607, the output variation control device 100 may proportionally control the variation rate limit value of the transmission power transmitted to the power system between the first variation rate and the second variation rate according to the adjusted control coefficient of the proportional controller 212. For example, the first rate of change may be 1%, and the second rate of change may be a preset value of 10%.

In step S609, the output variation control device 100 may determine the charge/discharge amount of the energy storage device 120 based on the variation rate limit value of the transmission power.

In step S611 , the output variation control device 100 may control the output variation of power by controlling the charging/discharging amount of the energy storage device 120 according to the determined charging/discharging amount of the energy storage device 120 .

Although not shown in FIG. 6 , in step S605 , the output variation control device 100 controls the proportional controller 212 by controlling the control coefficient of the proportional controller 212 in a first time interval in which the remaining energy amount of the energy storage device 120 is less than the remaining target energy amount. It can be set as 1 control coefficient.

Although not shown in FIG. 6, in step S605, the output variation control device 100 sets the control coefficient of the proportional controller 212 to the second time period in which the remaining energy amount of the energy storage device 120 exceeds the target remaining energy amount. It can be set as a control coefficient.

In the above description, steps S601 to S611 may be further divided into additional steps or combined into fewer steps, depending on the implementation of the present invention. Also, some steps may be omitted if necessary, and the order of steps may be changed.

7 is a flowchart illustrating a method of controlling an output variation of power generated in a renewable power plant according to another embodiment of the present invention.

The method for controlling output variation of power according to the embodiment shown in FIG. 7 is in the output variation control device 100, the renewable power plant 110 and the energy storage device 120 according to the embodiment shown in FIGS. 1 to 6. Steps are processed in time series. Therefore, even if the content is omitted below, the description of the output variation control device 100, the renewable power plant 110, and the energy storage device 120 of FIGS. 1 to 6 is according to the embodiment shown in FIG. It can also be applied to a method for controlling output variation of power.

Referring to FIG. 7 , in step S701, the power variation control device 100 may monitor power generated from the renewable power plant 110 and the remaining energy of the energy storage device 120 for each predetermined unit time.

When the energy storage device 120 is charged in step S703, the output variation control device 100 may determine whether the remaining energy amount of the energy storage device 120 is less than the target remaining energy amount in step S705.

In step S707, as a result of the determination in step S705, when the remaining energy amount of the energy storage device 120 is less than the remaining target energy amount, the output variation control device 100 sets the limiting value of the variation rate of the transmission power between the first variation rate and the second variation rate. can be linearly proportionally controlled in For example, the first rate of change may be 1%, and the second rate of change may be a preset value of 10%.

In step S709, when the remaining energy amount of the energy storage device 120 exceeds the target remaining energy amount as a result of the determination in step S705, the output variation control device 100 may fix the variation rate limit value to the second variation rate.

In step S711, when the energy storage device 120 is discharged, the output variation control device 100 may determine whether the remaining energy amount of the energy storage device 120 is less than the target remaining energy amount.

In step S713, when the remaining energy amount of the energy storage device 120 is less than the target remaining energy amount as a result of the determination in step S711, the output variation control device 100 may fix the variation rate limit value to the second variation rate.

In step S715, when the remaining energy amount of the energy storage device 120 exceeds the target remaining energy amount as a result of the determination in step S711, the output variation control device 100 sets the limiting value of the variation rate linearly between the first variation rate and the second variation rate. Proportional control is possible.

In step S717, the output variation control device 100 may determine the charge/discharge amount of the energy storage device 120 based on the variation rate limit value.

In step S719 , the output variation control device 100 may control the output variation of power by controlling the charging/discharging amount of the energy storage device 120 according to the determined charging/discharging amount of the energy storage device 120 .

In the above description, steps S701 to S719 may be further divided into additional steps or combined into fewer steps, depending on an embodiment of the present invention. Also, some steps may be omitted if necessary, and the order of steps may be changed.

An embodiment of the present invention may be implemented in the form of a recording medium including instructions executable by a computer, such as program modules executed by a computer. Computer readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. Also, computer readable media may include all computer storage media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

The above description of the present invention is for illustrative purposes, and those skilled in the art can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, the embodiments described above should be understood as illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and equivalent concepts thereof should be construed as being included in the scope of the present invention. .

100: output variation control device
110: renewable power plant
120: energy storage device

Claims (19)

In the output fluctuation control system for controlling the output fluctuation of electric power generated in a renewable power plant,
Generation power monitoring unit for monitoring the remaining energy of the power and energy storage system (ESS, Energy Storage System) generated in the renewable power plant;
a fluctuation rate limiting value setting unit for setting a fluctuation rate limiting value of transmission power transmitted to the power system based on the remaining energy of the energy storage device;
a charge/discharge amount determiner configured to determine a charge/discharge amount of the energy storage device based on the set variation rate limit value; and
An output variation controller configured to control the output variation of the power by controlling the charging and discharging of the energy storage device according to the determined charging and discharging amount.
Including, output variation control system.
According to claim 1,
The change rate limit value setting unit proportionally controls the change rate limit value between a first rate of change and a second rate of change based on the remaining energy amount; a proportional controller
To include, the output variation control system.
According to claim 2,
The first rate of change is the minimum rate of change, and the second rate of change is the maximum rate of change, the output fluctuation control system.
According to claim 2,
The fluctuation rate limit value setting unit is a target remaining energy amount setting unit that sets a target remaining energy amount of the energy storage device based on the hourly unit price of the power.
To include, the output variation control system.
According to claim 4,
The variation rate limit value setting unit controls a control coefficient adjusting unit for adjusting a control coefficient of the proportional controller when the remaining energy amount of the energy storage device reaches the remaining target energy amount.
Output variation control system further comprising a.
According to claim 4,
The control coefficient adjusting unit sets a control coefficient of the proportional controller as a first control coefficient in a first time period in which the remaining energy amount of the energy storage device is less than the remaining target energy amount,
In a second time interval in which the remaining energy of the energy storage device exceeds the remaining target energy. Output variation control system for setting the control coefficient of the proportional controller to the second control coefficient.
According to claim 6,
The slope for proportional control according to the first control coefficient is smaller than the slope for proportional control according to the second control coefficient.
According to claim 1,
The change rate limit value setting unit
When the energy storage device is being charged, in a first time period in which the remaining energy amount of the energy storage device is less than the remaining target energy amount, the variation rate limit value is linearly proportionally controlled between a first rate of change and a second rate of change,
and in a second time period in which the remaining energy amount of the energy storage device exceeds the remaining target energy amount, the rate of change limit value is fixed to the second rate of change.
According to claim 1,
The change rate limit value setting unit
When the energy storage device is discharging, in a first time interval in which the remaining energy amount of the energy storage device is less than the remaining target energy amount, the change rate limit value is fixed to a second change rate;
In a second time period in which the residual energy amount of the energy storage device exceeds the target energy residual amount, the variation rate limit value is linearly proportionally controlled between the first variation rate and the second variation rate. Output variation control system.
In an energy storage system (ESS, Energy Storage System),
A residual energy transmission unit for transmitting the residual energy amount to an output variation control system that monitors the residual energy amount for each predetermined unit time and controls the output variation of power generated in the renewable power plant;
a charge/discharge amount receiver configured to receive a charge/discharge amount from the output variation control system for each predetermined unit time; and
A charging and discharging unit for controlling the output variation of the power generated from the renewable power plant by charging and discharging according to the received charge and discharge amount.
including,
The charge/discharge amount is determined based on a limit value of the fluctuation rate of the transmission power transmitted to the power system,
The energy storage device, wherein the fluctuation rate limit value is set based on the remaining energy amount of the energy storage device.
According to claim 10,
Wherein the variation rate limit value is proportionally controlled between a first variation rate and a second variation rate based on the remaining energy amount.
According to claim 11,
Wherein the first rate of change is the minimum rate of change and the second rate of change is the maximum rate of change, the energy storage device.
In the method for controlling the output fluctuation of power generated in a renewable power plant performed in an output fluctuation control system,
Monitoring the remaining energy of power and energy storage system (ESS, Energy Storage System) generated in the renewable power plant;
setting a limit value for a variation rate of transmission power transmitted to a power system based on a residual amount of energy of the energy storage device;
determining a charge/discharge amount of the energy storage device based on the set variation rate limit value; and
Controlling the output variation of the power by controlling the charging and discharging of the energy storage device according to the determined charging and discharging amount.
A method for controlling output fluctuations of power, which includes a.
According to claim 13,
The step of setting the variation rate limit value of the transmission power
The variation rate limit value setting unit proportionally controlling the variation rate limit value between a first variation rate and a second variation rate based on the residual energy amount
A method for controlling output fluctuations of power, which includes a.
15. The method of claim 14,
The step of setting the variation rate limit value of the transmission power
Setting a target energy remaining amount of the energy storage device based on the hourly unit price of the power
To further include, a method for controlling the output fluctuation of power.
According to claim 15,
The step of setting the variation rate limit value of the transmission power
adjusting a control coefficient of the proportional controller when the remaining energy of the energy storage device reaches the remaining target energy;
To further include, a method for controlling the output fluctuation of power.
According to claim 15,
Adjusting the control coefficient of the proportional controller
setting a control coefficient of the proportional controller as a first control coefficient in a first time interval in which the remaining energy amount of the energy storage device is less than the remaining target energy amount; and
In a second time interval in which the remaining energy of the energy storage device exceeds the remaining target energy. Setting a control coefficient of the proportional controller as a second control coefficient
A method for controlling output fluctuations of power, which includes a.
According to claim 13,
The step of setting the variation rate limit value of the transmission power
When the energy storage device is charging, in a first time interval in which the remaining energy amount of the energy storage device is less than the remaining target energy amount, proportionally controlling the rate of change limit value in a linear manner between a first rate of change and a second rate of change; and
fixing the variation rate limit value to the second variation rate in a second time period in which the residual energy amount of the energy storage device exceeds the target energy residual amount;
A method for controlling output fluctuations of power comprising a.
According to claim 13,
The step of setting the variation rate limit value of the transmission power
fixing the variation rate limit value to a second variation rate in a first time interval in which the remaining energy amount of the energy storage device is less than the target remaining energy amount when the energy storage device is discharging; and
linearly proportionally controlling the variation rate limit value between the first variation rate and a second variation rate in a second time period in which the residual energy amount of the energy storage device exceeds the target energy residual amount;
A method for controlling output fluctuations of power, which includes a.

Images