KR102661065B1 - System for controlling output fluctuation of electric power, energe storage system and method - Google Patents

Abstract

The output fluctuation control system, which controls the output fluctuations of power generated from renewable power plants, includes a power monitoring unit and energy storage device that monitors the power generated from renewable power plants and the remaining energy of the energy storage system (ESS). A variation rate limit value setting unit that sets the variation rate limit value of the transmission power transmitted to the power system based on the energy remaining amount, a charge/discharge amount determination unit that determines the charge/discharge amount of the energy storage device based on the set change rate limit value, and an energy according to the determined charge/discharge amount. It may include an output variation control unit that controls output variation of power by controlling charging and discharging of the storage device.

Description

System, energy storage device, and method for controlling output fluctuations of power generated from renewable power plants {SYSTEM FOR CONTROLLING OUTPUT FLUCTUATION OF ELECTRIC POWER, ENERGE STORAGE SYSTEM AND METHOD}

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

Electric power generated from renewable power plants (e.g., wind power plants, solar power plants, etc.) experiences significant output fluctuations depending on weather conditions, topographical characteristics, and time of day. In addition, when power with output fluctuations is directly transmitted to the power system, power quality problems such as voltage fluctuations, frequency fluctuations, and stability deterioration may occur, and these problems can have a significant impact on the stable operation of the power system.

Accordingly, the need to stably transmit power generated from new and renewable power plants to the power system is emerging around the world, and preliminary research is in progress to apply legal regulations on output fluctuations.

For example, there are attempts to limit fluctuations in transmission power to the grid of new and renewable power plants to certain regulatory values depending on each country or power system operator, and control of energy storage devices to stabilize output to the conventional power system. Methods include Normal Ramp Rate (NRR) control method, Continuous Moving Average (CMA) control method, and Discrete Moving Average (DMA) control method.

In addition, methods for evaluating the output fluctuation rate of renewable power plant power include a method for evaluating the rate of change for the average value of composite output, a method for evaluating the rate of change for the difference between the maximum and minimum values, a method for evaluating the rate of change for the difference between the initial value and final value for 1 minute, etc. There is.

However, if the energy storage device is controlled to stabilize the output of renewable power generation without separate management of the remaining energy of the energy storage device, the energy storage device may operate biased toward charging or discharging according to the daily renewable power generation output pattern, resulting in overcharge. Otherwise, continuous operation may become impossible due to over-discharge.

Korean Patent Publication No. 2017-0002311, a prior art, discloses a configuration for setting the energy charge/discharge control mode of an energy storage device based on system scheduling based on a power variable rate plan and user scheduling that reflects user input.

In order to solve the above problems that arise from regulating the output variation rate of power to a constant value, the variation rate limit value of the transmission power transmitted to the power system is set within the regulated value based on the energy remaining amount of the energy storage device, and the set variation rate limit value is set. It is intended to control the output fluctuations of power generated from a renewable power plant by controlling the charging and discharging of the energy storage device according to the charging and discharging amount of the energy storage device determined based on the determined charging and discharging amount of the energy storage device. However, the technical challenges that this embodiment aims to achieve are not limited to the technical challenges described above, and other technical challenges may exist.

As a technical means for achieving the above-described technical problem, the output variation control system for controlling the output variation of power generated from a new and renewable power plant according to the first aspect of the present invention is a power and energy storage device generated from the new and renewable power plant. A generated power monitoring unit that monitors the remaining energy of the (ESS, Energy Storage System); a variation rate limit setting unit that sets a variation rate limit value of transmission power transmitted to the power system based on the remaining energy of the energy storage device; a charge/discharge amount determination unit that determines a charge/discharge amount of the energy storage device based on the set variation rate limit value; And it may include an output fluctuation control unit that controls the output fluctuation of the power by controlling charging and discharging of the energy storage device according to the determined charging and discharging amount.

The energy storage system (ESS) according to the second aspect of the present invention is an output fluctuation control system that controls the output fluctuation of power generated from a renewable power plant by monitoring the energy residual amount at a preset unit time. a residual energy transmission unit that transmits; a charging/discharging amount receiving unit that receives a charging/discharging amount from the output variation control system at each preset unit time; and a charge/discharge unit that controls output fluctuations of power generated from the renewable power plant by charging and discharging according to the received charge/discharge amount, wherein the charge/discharge amount is determined based on a change rate limit value of the 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.

The method of controlling the output variation of power generated from a renewable power plant performed in the output variation control system according to the third aspect of the present invention is the power generated from the renewable power plant and the energy storage system (ESS). monitoring energy remaining; setting a change rate limit value of transmission power transmitted to the power system based on the remaining energy of the energy storage device; determining a charge/discharge amount of the energy storage device based on the set variation rate limit; And it may include controlling the output variation of the power by controlling charging and discharging of the energy storage device according to the determined charging and discharging amount.

The above-described means for solving the problem are merely 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 of the invention.

According to one of the means for solving the problem of the present invention described above, a change rate limit value of the transmission power transmitted to the power system is set based on the energy remaining amount of the energy storage device, and the charging and discharging amount of the energy storage device determined based on the set change rate limit value. Since the charging and discharging of the energy storage device is controlled according to the system, power can be stably supplied to the power system while meeting the fluctuation rate regulations.

In addition, because it controls output fluctuations of power generated from new and renewable power plants, it is possible to satisfy grid connection regulations for new and renewable power plants.

In addition, since the charging and discharging of the final energy storage device is determined based on the remaining energy of the energy storage device, biased charging and discharging of the battery can be prevented, and taking into account the continuous operation of the energy storage device and the power price by time period or various subsidies Profits can be increased by strategically adjusting the charging and discharging amount of energy storage devices.

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

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts unrelated to the description are omitted, and similar parts are given similar reference numerals 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 in between. . Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

In this specification, 'part' includes a unit realized by hardware, a unit realized by software, and a unit realized using both. Additionally, one unit may be realized using two or more pieces of hardware, and two or more units may be realized using one piece of hardware.

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

Hereinafter, specific details for implementing the present invention will be described with reference to the attached configuration diagram or processing flow diagram.

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

Referring to FIG. 1, the output 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 limited to FIG. 1, and may be configured differently from FIG. 1 according to various embodiments of the present invention. .

The output fluctuation 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 every preset 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 at preset unit times and monitor changes in the remaining energy amount.

The output fluctuation control device 100 sets a fluctuation rate limit value of the transmission power transmitted to the power system based on the energy remaining amount of the energy storage device 120, and sets the charging and discharging amount of the energy storage device 120 based on the set fluctuation rate limit value. You can decide.

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

The renewable power plant 110 can generate power using an energy source. The renewable power plant 110 may include, for example, a power generation system that generates electricity using renewable energy such as solar heat or geothermal heat.

The transmitted power transmitted to the power system may vary depending on the charging and discharging amount determined by the output change control device 100.

The energy storage device 120 may receive information about the charging and discharging amount every preset unit time from the output variation control device 100. The energy storage device 120 may charge and discharge power according to information about the amount of charging and discharging received at each preset unit time.

Generally, each component of the output variation control system of FIG. 1 is connected through a network (not shown). Network refers to a connection structure that allows information exchange between nodes such as terminals and servers, including Local Area Network (LAN), Wide Area Network (WAN), and World Wide Area Network (WWW). Wide Web), wired and wireless data communication networks, telephone networks, wired and wireless television communication networks, etc. Examples of wireless data communication networks include 3G, 4G, 5G, 3GPP (3rd Generation Partnership Project), LTE (Long Term Evolution), WIMAX (World Interoperability for Microwave Access), Wi-Fi, Bluetooth communication, infrared communication, and ultrasound. This includes, but is not limited to, communication, Visible Light Communication (VLC), LiFi, etc.

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 the 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 change rate limit value setting unit 210 may include a proportional controller 212, a target energy remaining amount 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 the power generated from the renewable power plant 110 and the remaining energy of the energy storage device 120. For example, the generated power monitoring unit 200 collects the amount of power generated per preset unit time from the renewable power plant 110, and charges and discharges the energy storage device 120 per 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.

The variation rate limit 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 limit setting unit 210 may change the variation rate limit value of the transmission power transmitted to the power system for each preset unit time or for each separately set unit time.

The variation rate limit value setting unit 210 may use 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 change rate may be 1% and the second change rate may be 10%. At this time, the first change rate is the minimum change rate, and the second change rate means the maximum change rate that cannot exceed the preset change rate regulation value. However, the final change rate cannot exceed the change rate regulation value.

For example, the variation rate limit setting unit 210 may adjust the variation rate limit value to converge to the second variation rate as the energy remaining amount of the energy storage device 120 approaches the preset highest charging capacity, and the energy remaining amount may be adjusted to the preset maximum charging capacity. As the charging capacity approaches the minimum, the variation rate limit value can be adjusted to converge to the first variation rate.

The target energy remaining amount setting unit 214 may set the target energy remaining 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 to the first time zone when the unit price of power is low (e.g., 10:00 to 16:00 in the case of a solar power plant). It can be set high as the target energy remaining amount. In this case, the energy storage device 120 can store the power generated by the renewable power plant 110 up to the first target energy remaining amount during times when power generation costs are low. In contrast, 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 zone when the unit price of power is high (for example, in the case of a solar power plant, times other than 10:00 to 16:00). 1 It can be set to a second target energy remaining amount that is lower than the target energy remaining amount.

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

In this way, by setting the target energy residual amount of the energy storage device 120 based on the hourly unit price of power or setting different weights for the amount of transmitted power, the energy residual amount is increased at times when the hourly unit price is low, and the hourly unit price is lower. During high times, you can make a lot of profit by discharging your energy.

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

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

Referring to FIG. 4A, when the energy storage device 120 charges and discharges in the first time period 407, the variation rate limit setting unit 210 sets the variation rate of the transmitted power according to the first control coefficient of the proportional controller 212. The limit value can be linearly proportionally controlled between the first change rate 403 and the second change rate 405.

When the energy storage device 120 charges and discharges in the second time section 409, the variation rate limit setting unit 210 sets the variation rate limit value of the transmitted power to the first variation rate ( 403) and the second change rate 405 can be linearly proportionally controlled.

The control coefficient adjusting unit 216 sets the control coefficient of the proportional controller 212 as the first control coefficient in the first time section 407 when the energy remaining amount of the energy storage device 120 is less than the target energy remaining amount 401. You can set it.

The control coefficient adjusting unit 216 adjusts the control coefficient of the proportional controller 212 to the second control coefficient in the second time period 409 when the energy residual amount of the energy storage device 120 exceeds the target energy residual amount 401. You can set it.

Here, the slope 413 for proportional control according to the second control coefficient may be set to be larger than the slope 411 for proportional control according to the first control coefficient. In other words, the change in the change rate limit value, which is proportionally controlled according to the second control coefficient of the proportional controller 212 in the second time section 409, is affected by the first control coefficient of the proportional controller 212 in the first time section 407. This means that the change is greater than the change rate limit value that is proportionally controlled.

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 period 407 is prevented. It is possible to prevent overcharging of the energy storage device 120 in the second time period 409.

Additionally, by setting the slope 413 for proportional control to be large in the second time section 409, the energy storage device 120 can continuously retain energy corresponding to the target energy remaining amount.

As explained in Figure 4a, when controlling the variation limit value by varying the slope of the proportional control based on the target energy remaining amount, a certain amount of power output variation must be allowed, which causes a problem in that a steady-state error occurs. .

This problem of occurrence of steady-state error can be solved by fixing the variation rate limit value based on the target energy remaining amount when proportionally controlling the change rate limit value.

Referring to FIG. 4B, when the energy storage device 120 is charged, as shown in reference numeral (a), the change rate limit value setting unit 210 sets the energy remaining amount of the energy storage device 120 to the target energy remaining amount 401. In the first time section 407, the change rate limit value is linearly proportionally controlled between the first change rate 403 and the second change rate 405, and the energy remaining amount of the energy storage device 120 is adjusted to the target energy remaining amount 401. ), the change rate limit value may be fixed to the second change rate 405.

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

The output variation control unit 230 may control the output variation of power by controlling 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 every preset unit time. Additionally, the output variation control unit 230 may command the energy storage device 120 to charge and discharge based on the determined charge and discharge amount.

In this way, the present invention controls the output fluctuation of power generated from a new and renewable power plant according to the remaining energy, so that energy corresponding to the target energy remaining amount of the energy storage device can be maintained at a constant level, and the output fluctuation rate of existing power can be reduced. If the value is fixed to a certain value, the problem of overdischarging or overcharging of the energy storage device that occurs can be solved.

Meanwhile, those skilled in the art will know that the generated power monitoring unit 200, the variation rate limit setting unit 210, the proportional controller 212, the target energy remaining amount setting unit 214, the control coefficient adjusting unit 216, and the charge/discharge amount determination unit 220. ) and the output change control unit 230 may be implemented separately, 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 an embodiment of the present invention.

Referring to FIG. 3 , the energy storage device 120 may include a remaining energy transmitter 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 energy residual amount transmission unit 300 may monitor the energy residual amount at a preset unit time and transmit the monitored energy residual amount to the output variation control device 100, which controls the output variation of power generated from the renewable power plant 110. there is.

For example, the energy residual amount transmission unit 300 distinguishes the energy residual amount when the energy storage device 120 is discharging and the energy residual amount when the energy storage device 120 is charging and transmits the energy residual amount to the output change control device 100. Can be transmitted.

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

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

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

As another example, when the energy storage device 120 is charging, the change rate limit value in the first time section is linearly proportionally controlled between the first change rate and the second change rate, and the change rate limit value in the second time section is the second change rate. It can be fixed as . When the energy storage device 120 is discharging, the change rate limit value in the first time section is fixed to the second change rate, and the change rate limit value in the second time section is linearly proportionally controlled between the first change rate and the second change rate. You can.

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

Meanwhile, those skilled in the art will fully understand that the remaining energy transmission unit 300, the charging/discharging amount receiving unit 310, and the charging/discharging unit 320 may be implemented separately, or one or more of them may be integrated and implemented.

Figure 5 is a flowchart showing a method of controlling output fluctuations of power generated from 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 used 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 4B. It includes steps that are processed in time series. Therefore, even if the content is omitted below, the content described regarding the output variation control device 100, the renewable power plant 110, and the energy storage device 120 of FIGS. 1 to 4B are the same as those according to the embodiment shown in FIG. 5. It can also be applied to a method of controlling power output fluctuations.

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

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

In step S505, the output variation control device 100 may determine the charging and discharging 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 and discharging amount of the energy storage device 120 according to the determined charging and 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. Additionally, some steps may be omitted or the order between steps may be changed as needed.

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

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

Referring to FIG. 6 , in step S601, the output fluctuation control device 100 may monitor the power generated from the renewable power plant 110 and the remaining energy of the energy storage device 120 at each preset unit time.

In step S603, the output fluctuation control device 100 may set the 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 energy remaining amount of the energy storage device 120 reaches the target energy remaining 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 control coefficient of the adjusted proportional controller 212. For example, the first change rate may be 1%, and the second change rate may be a preset value of 10%.

In step S609, the output change control device 100 may determine the charging and discharging amount of the energy storage device 120 based on the change rate limit value of the transmitted power.

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

Although not shown in FIG. 6, in step S605, the output variation control device 100 sets the control coefficient of the proportional controller 212 in the first time period when the energy residual amount of the energy storage device 120 is less than the target energy residual amount. It can be set as 1 control coefficient.

Although not shown in FIG. 6, in step S605, the output variation control device 100 adjusts the control coefficient of the proportional controller 212 to a second time interval in a second time period when the energy residual amount of the energy storage device 120 exceeds the target energy residual 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. Additionally, some steps may be omitted or the order between steps may be changed as needed.

Figure 7 is a flowchart showing a method of controlling output fluctuations of power generated from a renewable power plant according to another embodiment of the present invention.

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

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

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

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

In step S709, when the remaining energy of the energy storage device 120 exceeds the target energy remaining 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 of the energy storage device 120 is less than the target energy remaining amount.

In step S713, if the remaining energy of the energy storage device 120 is less than the target energy remaining 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, if the energy residual amount of the energy storage device 120 exceeds the target energy residual amount as a result of the determination in step S711, the output change control device 100 sets the change rate limit value linearly between the first change rate and the second change rate. Proportional control is possible.

In step S717, the output variation control device 100 may determine the charging and discharging 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 and discharging amount of the energy storage device 120 according to the determined charging and 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 the implementation of the present invention. Additionally, some steps may be omitted or the order between steps may be changed as needed.

One embodiment of the present invention may also be implemented in the form of a recording medium containing 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 non-volatile media, removable and non-removable media. Additionally, computer-readable media may include all computer storage media. Computer storage media includes both volatile and non-volatile, 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 description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts 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 device for controlling the output fluctuation of power generated from a renewable power plant,
A generated power monitoring unit that monitors the power generated from the renewable power plant and the remaining energy of an energy storage system (ESS);
a variation rate limit setting unit that sets a variation rate limit value of transmission power transmitted to the power system based on the remaining energy of the energy storage device;
a charge/discharge amount determination unit that determines a charge/discharge amount of the energy storage device based on the set variation rate limit value; and
An output fluctuation control unit that controls the output fluctuation of the power by controlling charging and discharging of the energy storage device according to the determined charging and discharging amount.
Including,
The change rate limit setting unit,
a proportional controller that controls the change rate limit value between a first change rate and a second change rate in proportion to a control coefficient based on the remaining energy; and
A control coefficient adjustment unit that adjusts the control coefficient when the energy remaining amount of the energy storage device reaches a preset target energy remaining amount.
An output variation control device comprising:
According to claim 1,
The first change rate is the minimum change rate, and the second change rate is the maximum change rate.
According to claim 1,
The target energy remaining amount is set based on the hourly unit price of the power.
According to claim 1,
The control coefficient adjusting unit sets the control coefficient of the proportional controller to a first control coefficient in a first time period when the energy remaining amount of the energy storage device is less than the target energy remaining amount,
An output variation control device that sets the control coefficient of the proportional controller to a second control coefficient in a second time period when the energy residual amount of the energy storage device exceeds the target energy residual amount.
According to claim 4,
An output variation control device wherein 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.
In the output fluctuation control device for controlling the output fluctuation of power generated from a renewable power plant,
A generated power monitoring unit that monitors the power generated from the renewable power plant and the remaining energy of an energy storage system (ESS);
a rate limit value setting unit including a proportional controller that proportionally controls a change rate limit value of power transmitted to the power system between a first change rate and a second change rate based on the remaining energy of the energy storage device;
a charge/discharge amount determination unit that determines a charge/discharge amount of the energy storage device based on the set variation rate limit value; and
An output fluctuation control unit that controls the output fluctuation of the power by controlling charging and discharging of the energy storage device according to the determined charging and discharging amount.
Including,
The variation rate limit setting unit uses the proportional controller to set a variation rate limit value between a first variation rate and a second variation rate so that the variation rate limitation value of the transmitted power is proportional to the remaining energy of the energy storage device.
According to claim 6,
The variation rate limit value setting unit adjusts the variation rate limit value to converge to the second variation rate as the remaining energy of the energy storage device approaches the preset highest charging capacity, and the remaining energy of the energy storage device approaches the preset lowest charging capacity. The output variation control device adjusts the variation rate limit value to converge to the first variation rate as it approaches.
In an energy storage system (ESS),
An energy remaining amount transmission unit that monitors the remaining energy amount at a preset unit time and transmits the remaining energy amount to an output fluctuation control device that controls output fluctuations of power generated from a renewable power plant;
a charging/discharging amount receiving unit that receives a charging/discharging amount from the output change control device at each preset unit time; and
A charging and discharging unit that controls output fluctuations of power generated from the renewable power plant by charging and discharging according to the received charging and discharging amount.
Including,
The charging and discharging amount is determined based on the change rate limit value of the transmitted power transmitted to the power system,
The fluctuation rate limit value is set based on the energy remaining amount of the energy storage device,
When the remaining energy amount reaches a preset target energy remaining amount, the control coefficient of the proportional controller is adjusted so that the change rate limit value is proportionally controlled between the first change rate and the second change rate.
According to claim 8,
The first change rate is the minimum change rate, and the second change rate is the maximum change rate.
In a method of controlling the output fluctuation of power generated from a renewable power plant performed by an output fluctuation control device,
Monitoring the power generated from the renewable power plant and the remaining energy of an energy storage system (ESS);
setting a change rate limit value of transmission power transmitted to the power system based on the remaining energy of the energy storage device;
determining a charge/discharge amount of the energy storage device based on the set variation rate limit; and
Controlling the output fluctuation of the power by controlling charging and discharging of the energy storage device according to the determined charging and discharging amount
Including,
The step of setting the change rate limit value of the transmitted power is,
controlling the change rate limit value between a first change rate and a second change rate in proportion to a control coefficient based on the energy remaining amount; and
When the energy remaining amount of the energy storage device reaches a preset target energy remaining amount, adjusting the control coefficient
A method for controlling output fluctuations of power, comprising:
According to claim 10,
The target energy remaining amount is set based on the hourly unit price of the power.
According to claim 10,
The step of adjusting the control coefficient is
In a first time period when the energy remaining amount of the energy storage device is less than the target energy remaining amount, setting the control coefficient as a first control coefficient; and
In a second time period when the energy remaining amount of the energy storage device exceeds the target energy remaining amount, setting the control coefficient as a second control coefficient.
A method for controlling output fluctuations of power, comprising:
According to claim 12,
A method for controlling output variation of power, wherein 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. delete delete delete delete delete delete