KR102234526B1 - SoC Management System and Method using Frequency Control and Adaptive Control at ESS Interfacing Generation Plant - Google Patents

Abstract

In the present invention, when the power system frequency fluctuates, the ESS (Energy Storage System) controls the frequency according to the droop slope, then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC frequency tracking control of the power generation-linked ESS. And an SoC management device and method using adaptive control, which senses that the frequency of the power system fluctuates according to the output fluctuation or load fluctuation of a generator through an electrical network, and automatic power generation control and speed control (Speed Changer). When the power system frequency fluctuates in connection with the power generation control unit and the generator, the ESS controls the frequency according to the droop slope and then changes the slope and reduces the charge/discharge value of the ESS to manage the SoC; valve (Valves) ) Control, turbine (Turbine) through the control of the frequency of the power system to maintain the rated frequency by adjusting the power generation power or through the auxiliary adjustment of the load increase or decrease, the power generation unit having a generator that generates power; to include.

Description

SOC Management System and Method using Frequency Control and Adaptive Control at ESS Interfacing Generation Plant}

The present invention relates to power system control, and specifically, when the power system frequency fluctuates, frequency control is performed according to the droop slope, and then the slope is changed, the frequency of the power generation-linked ESS that reduces the charge/discharge value of the ESS and manages the SoC. It relates to an SoC management apparatus and method using tracking control and adaptive control.

The power system refers to a system in which a power plant, a substation, and a load are connected by a transmission line in response to electricity demand, from generation to consumption of electricity.

In such a power system, since power generation and consumption occur at the same time, demand and supply must be balanced. Accordingly, the power system requires continuous monitoring of the balance between supply and demand.

As the problem of unbalanced electricity supply and demand intensifies every year, ESS has recently been in the spotlight as a way to solve this problem.

ESS (Energy Storage System) is an energy storage system that controls various voltages/currents generated from distributed power or renewable energy, and connects to the power system or stores and uses idle energy as needed. Considering the enormous cost and construction time required for power plant investment against the increasing power demand, ESS has the advantages of equalizing power demand, stable operation of the power system, and active management.

In addition, ESS is essential for an efficient plan to increase the efficiency of use of smart grids and new and renewable energy, as new and renewable energies such as smart grids and solar or wind power generation are in the spotlight.

ESS has advantages such as power quality, maintenance, time shift, and energy conservation, thereby reducing investment in power plant facilities, improving power quality of new and renewable energy, and minimizing damage during power outages.

A typical energy storage system (ESS) includes a storage device (Battery), a Power Conditioning Syaetm (PCS), an Energt Management System (EMS), and a Battery Management System (BMS).

In power generation areas such as power generation sources, the emergence of new and renewable energy and small-scale distributed power generation has led to the emergence of large-scale and subdivided areas. In the transmission/distribution area, reserve capacity, The areas of power grid load distribution and frequency adjustment are emerging.

At the end user level, there are needs in various sub-markets for each purpose, such as energy storage to respond to peak demand, storage of renewable energy generation, and output response during power outages, and related ESS projects are rapidly increasing.

In ESS, the frequency regulation is to improve the supply capacity by adjusting the output frequency of the generator in operation to prevent power frequency fluctuations due to instantaneous demand fluctuations.

ESS in connection with such renewable energy needs to be accompanied by research on the problem of frequency adjustment and power peak adjustment.

In the prior art, each operated like a single ESS and a single power plant, and in the case of an ESS, the ESS was connected to a transmission network or a distribution network without a power plant connection.

As described above, in the prior art, when it detects that the frequency of the power system fluctuates due to fluctuations in the output or load of the generator, the frequency of the power system is adjusted to maintain the rated frequency, or the frequency mainsboat function is performed. In conjunction with the function, it performs auxiliary adjustment functions such as adjusting the power generation power of the linked power plant or increasing or decreasing the load.

Accordingly, a delay time occurs from the time when the output fluctuation or the load fluctuation of the power plant is found to the time when the frequency of the power system is fluctuated to perform frequency adjustment, and the power system frequency may decrease or increase during the delay time.

On the supplier side, if the frequency of the power system decreases during the delay time, there is a problem that the output of power plant auxiliary equipment and the control system may become unstable. If the frequency of the power system increases during the delay time, the frequency decreases. There is a problem that the limit width for continuous operation is less than that of the case.

In order to solve such a problem, a technology has been proposed in which an ESS (Energy Storage System) is connected to a generator and the ESS performs frequency correction in consideration of the operating conditions of the generator.

1 is a state diagram of SoC management and control of a conventional power generation-linked ESS.

SoC management control of power generation-linked ESS is to use ESS to maintain frequency regulation (frequency regulation) in order to maintain the reference frequency of 60Hz.

That is, the frequency of the system changes according to the load of the system, and when the system frequency decreases to 59.97Hz or less due to an increase in the load, the ESS is discharged to supply power to the system, and the frequency is 60.03Hz or more due to a decrease in the load. When rising to, the ESS is charged with electric power to maintain the frequency.

If the frequency is within the operating range and the SoC of the ESS is out of a certain range, it operates to keep the SoC within the operating range. The ESS output for SoC recovery operation discharges 10% or 15% of the rated output according to the SoC status.

By using the droop coefficient that determines the output of the ESS for the amount of frequency change, the ESS performs droop control for power system frequency correction, and changes the charge/discharge value to 0 when reducing the power value of the ESS after charging or discharging.

When the SoC is 80% or more, the energy storage device controls discharge, and when the SoC is less than 50%, it is controlled so that only charging according to the remaining SoC is possible.

However, the power system control technology using such a power generation-linked ESS has a limitation in stabilizing the frequency of the power system due to a large impact on the power grid when the power value changes abruptly.

Therefore, there is a need to develop a new control technology for stabilizing the frequency of the power system.

Republic of Korea Patent Publication No. 10-2019-0004587 Republic of Korea Patent Publication No. 10-2016-0028885 Republic of Korea Patent Publication No. 10-2016-0082271

The present invention is to solve the problem of the power system control technology of the prior art, when the power system frequency fluctuates, the ESS (Energy Storage System) controls the frequency according to the droop slope and then changes the slope to charge and discharge the ESS. Its purpose is to provide an SoC management apparatus and method using frequency tracking control and adaptive control of a power generation-linked ESS that reduces the value and manages the SoC.

The present invention is connected to a generator to control droop for power system frequency correction, and after charging or discharging, when reducing the power value of the ESS, the charge/discharge value is not changed to 0, but is droop in an adaptive control method. ) The purpose of this is to provide an SoC management apparatus and method using frequency tracking control and adaptive control of power generation-linked ESS that gradually changes the slope.

In the present invention, when the power system frequency fluctuates, the ESS controls the frequency according to the droop slope, then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC, so that the ESS reduces the charge/discharge value and the generator supplies power at the same time. The purpose of this is to provide an SoC management apparatus and method using frequency tracking control and adaptive control of a power generation-linked ESS that is made efficient.

The present invention is an adaptive control method in which the droop slope is gradually changed and reduced, so that charging and discharging is gradually reduced rather than abruptly, so it is helpful for SoC management, and it is a power generation-linked type that can be helpful when charging or discharging in the future. The purpose of this is to provide an SoC management apparatus and method using frequency tracking control and adaptive control of ESS.

In the present invention, since the change in the power value of the ESS does not change rapidly, the power supply of the ESS decreases in the generator + ESS combination, and the generator can naturally enter when the power supply of the generator increases, thereby reducing the impact on the power grid. The purpose of this is to provide an SoC management apparatus and method using frequency tracking control and adaptive control of a linked ESS.

Other objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

The SoC management device using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention to achieve the above object is the frequency of the power system according to the output fluctuation or load fluctuation of the generator through an electrical network. A power generation control unit that senses a fluctuation of the power generation and performs automatic power generation control and speed control (Speed Changer); When the power system frequency fluctuates in connection with the power generation control unit and the generator, the ESS controls the frequency according to the droop slope and then changes the slope. ESS that manages SoC by reducing the charge/discharge value of; Generator that generates power by adjusting the power generation power so that the frequency of the power system maintains the rated frequency through valve control and turbine control, or through auxiliary adjustment of load increase or decrease. It characterized in that it comprises a; power generation unit having.

Here, the ESS and the power generation unit communicate with each other in the process of frequency tracking control and adaptive control to perform cooperative control, so that the generator and the ESS share the role of frequency control.

In addition, the ESS controls droop, and when charging or discharging, and then reducing the power value of the ESS, instead of changing the charging/discharging value to 0, the droop slope is gradually changed in an adaptive control method to facilitate SoC management. Characterized in that.

In addition, the ESS controls the frequency according to the droop slope, then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC, so that the ESS reduces the charge/discharge value and at the same time converts the generator to supply power. It is characterized by that.

_{In addition, the ESS is a first for comparing the frequency control deadband upper limit (f H} ) and the measurement frequency (f) by measuring the frequency (f) of the SOC and the power system of the corresponding section for frequency tracking control and adaptive control. In the system frequency comparison unit and the first system frequency comparison unit, if the measurement frequency (f) does _{not exceed the frequency control deadband upper limit (f H} ), the frequency control deadband region lower limit (f _L ) and the measurement frequency (f) are compared. When the measured frequency (f) in the second system frequency comparison unit and the first system frequency comparison unit _{exceeds the upper limit of the frequency control deadband area (f H} ), the current SOC value and the SOC overcharge prevention mode division line (SOC _H2 ) are compared. In the first SOC comparison unit and the second system frequency comparison unit, if the measurement frequency (f) does _{not exceed the lower limit of the frequency control deadband area (f L} ), the current SOC value and the overdischarge prevention mode division line (SOC _L2 ) are compared. 2 In the SOC comparison unit and the second system frequency comparison unit, if the measured frequency (f) _{is not less than the frequency control deadband lower limit (f L} ), the current SOC value is SOC control deadband lower limit (SOC _L1 ) and the SOC control is dead. It characterized in that it comprises a third SOC comparison unit to determine whether it is located between the large area upper limit (SOC _H1).

In addition, the current SOC value in the first SOC comparison unit _{is greater than the SOC overcharge prevention mode division line (SOC H2} ), or the current SOC value in the second SOC comparison unit _{is less than the overdischarge protection mode division line (SOC L2} ), or the third In the SOC comparison unit, if the current SOC value is _{not located between the lower limit of the SOC control deadband area (SOC L1} ) and the upper limit of the SOC control deadband area (SOC _H1 ), the SoC management is performed by changing the drop slope in an adaptive control method. It characterized in that it further comprises an adaptive droop control unit.

의 크기로 충방전을 제어하는 ESS 충방전 제어부를 더 포함하는 것을 특징으로 한다.And if the current SOC value in the first SOC comparison unit does _{not exceed the SOC overcharge prevention mode division line (SOC H2} ), or when the current SOC value in the second SOC comparison unit exceeds the overdischarge prevention mode division line (SOC _L2 ),

It characterized in that it further comprises an ESS charge and discharge control unit for controlling the charge and discharge in the size of.

And if the current SOC value in the third SOC comparison unit is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ), the ESS charge/discharge value is set to 0 (P _ESS = 0). It characterized in that it further comprises an ESS charging and discharging value changing unit to change.

The SoC management method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention to achieve another object is to measure the frequency (f) of the SOC and the power system, and the upper limit of the frequency control deadband area (f _H ) And a first system frequency comparison step of comparing the measured frequency (f); If the measured frequency (f) does _{not exceed the upper limit of the frequency control deadband area (f H} ) in the first system frequency comparison step, the lower limit of the frequency control deadband area ( f _L ) and the second system frequency comparison step of comparing the measured frequency (f); If the measured frequency (f) _{exceeds the upper limit of the frequency control deadband area (f H} ) in the first system frequency comparison step, the current SOC value and the SOC are overcharged. The first SOC comparison step for comparing the prevention mode division line (SOC _H2 ); in the second system frequency comparison step, if the measured frequency (f) does _{not exceed the lower limit of the frequency control deadband area (f L} ), the current SOC value and overdischarge prevention mode The second SOC comparison step of comparing the division line (SOC _L2 ); in the second system frequency comparison step, if the measured frequency (f) _{is not less than the frequency control deadband region lower limit (f L} ), the current SOC value is the SOC control deadband region lower limit A third SOC comparison step of determining whether it is located between the SOC _L1 and the upper limit of the SOC control deadband SOC _H1 , and SOC management by changing a droop slope in an adaptive control method. do.

Here, in the first SOC comparison step, the current SOC value is _{greater than the SOC overcharge prevention mode dividing line (SOC H2} ), the second SOC comparison step, the current SOC value is less than the _{overdischarge prevention mode dividing line (SOC L2), or} 3 In the SOC comparison stage, if the current SOC value is _{not located between the lower limit of the SOC control deadband area (SOC L1} ) and the upper limit of the SOC control deadband area (SOC _H1 ), change the drop slope in an adaptive control method to manage SoC. It characterized in that the adaptive droop control step is performed.

의 크기로 충방전을 제어하는 ESS 충방전 제어 단계를 수행하는 것을 특징으로 한다.And if the current SOC value does not exceed the SOC overcharge prevention mode divider line (SOC _H2 ) in the first SOC comparison step, or the current SOC value exceeds the overdischarge prevention mode divider line (SOC _L2 ) in the second SOC comparison step.

It characterized in that it performs the ESS charge/discharge control step of controlling charge and discharge with the size of.

And in the third SOC comparison step, if the current SOC value is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ), the ESS charge/discharge value is set to 0 (P _ESS = 0). It characterized in that performing the step of changing the ESS charge/discharge value to be changed.

In addition, in order to manage SOC by changing the droop slope in an adaptive control method, the SOC change step of outputting ΔSOC by changing the power to SOC, and the SOC value conversion _{of changing the ΔSOC value (K R) for frequency feedback.} by the steps, and a fluctuation frequency (Δf) and converting SOC value droop (droop) tilt (R) change control (K _D) to (K _R) to the input, characterized in that it comprises a P _SOC outputting step for outputting P _SOC do.

및,

으로 정의되는 것을 특징으로 한다.And P _SOC and ΔSOC are,

And,

It characterized in that it is defined as.

인 경우에서,

이면

이고,

이면,

으로 정의되고,

인 경우에서

이면

이고,

이면

으로 정의되는 것을 특징으로 한다.And droop gradient change control (K _D ),

In the case of,

Back side

ego,

If,

Is defined as,

In case

Back side

ego,

Back side

It characterized in that it is defined as.

The SoC management apparatus and method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention as described above has the following effects.

First, when the power system frequency fluctuates, the ESS (Energy Storage System) controls the frequency according to the droop slope, then changes the slope, and reduces the charge/discharge value of the ESS, so that the SoC can be efficiently managed.

Second, it is connected to the generator to control droop for power system frequency correction, and after charging or discharging, when the power value of the ESS is reduced, the charge/discharge value is not changed to 0, but is droop in an adaptive control method. Efficient SoC management is possible by gradually changing the slope.

Third, the ESS controls the frequency according to the droop slope, then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC, so that the ESS reduces the charge/discharge value, and at the same time, the conversion of the generator supplying power is made efficiently.

Fourth, the adaptive control method gradually changes the droop slope and decreases it gradually, rather than abruptly reducing charging and discharging, so it is helpful in SoC management, and it can be helpful when charging or discharging in the future.

Fifth, since the change in the power value of the ESS does not change rapidly, the power supply of the ESS decreases in the generator + ESS combination, and the generator can naturally enter when the power supply of the generator increases, thereby reducing the impact on the power grid.

1 is a state diagram of SoC management and control of a conventional power generation-linked ESS
2 is a block diagram of an SoC management apparatus using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention
3 is a detailed configuration diagram of an SoC management apparatus using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention
Figure 4 is a state diagram of SoC management control of the power generation-linked ESS according to the present invention
5 is a graph showing a droop slope change method according to the present invention
6 is a block diagram of the SoC management control unit of the power generation-linked ESS according to the present invention
7 is a flow chart showing a SoC management method using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention

Hereinafter, a preferred embodiment of an SoC management apparatus and method using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention will be described in detail as follows.

Features and advantages of the SoC management apparatus and method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention will be apparent through detailed description of each embodiment below.

2 is a block diagram of an SoC management apparatus using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention.

The SoC management apparatus and method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention, when the power system frequency fluctuates, the ESS (Energy Storage System) performs frequency control according to the droop slope and then changes the slope. It is designed to efficiently manage SoC by reducing the charge/discharge value of ESS.

To this end, the present invention is connected to a generator to control droop for power system frequency correction, and when charging or discharging the power value of the ESS, when reducing the power value of the ESS, the charging/discharging value is drooped in an adaptive control method instead of changing to 0. (Droop) It can include a configuration that manages the SoC by gradually changing the slope.

In the present invention, the ESS controls the frequency according to the droop slope and then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC, so that the ESS reduces the charge/discharge value and at the same time, the conversion in which the generator supplies power is efficiently achieved. It may include a configuration that allows it to be built.

The SoC management apparatus using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention is the power system according to the output fluctuation or load fluctuation of the generator through the electrical network 100, as shown in FIG. The power generation control unit 200 that senses the frequency change and performs automatic power generation control and speed control (Speed Changer), and when the power system frequency fluctuates in connection with the power generation control unit 200 and the generator, the frequency is changed according to the droop slope. The power generation is adjusted so that the frequency of the power system maintains the rated frequency through the ESS (300), which manages the SoC by changing the slope during control and reducing the charge/discharge value of the ESS, and the valve control and turbine control. It includes a power generation unit 400 having a generator that generates power through auxiliary adjustments such as load increase or decrease, and a power system stabilization unit 500 that performs power system stabilization through PSS (Power System Stabilization), Exciter, and Voltage Sensing. do.

Here, the ESS 300 and the power generation unit 400 communicate with each other in the process of frequency tracking control and adaptive control to perform cooperative control so that the generator and the ESS share the role of frequency control. After frequency correction and frequency fluctuation occurs, SoC is adjusted to quickly control the frequency by utilizing the fast response characteristics of ESS.

In addition, the ESS 300 controls droop and gradually changes the droop slope in an adaptive control method instead of changing the charge/discharge value to 0 when reducing the power value of the ESS after charging or discharging. It is to manage.

In addition, the ESS 300 controls the frequency according to the droop slope, then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC, so that the ESS reduces the charge/discharge value and at the same time, the conversion in which the generator supplies power is efficient. It should be done with.

The power generation-linked ESS according to the present invention includes the following configurations for frequency tracking control and adaptive control.

3 is a detailed configuration diagram of an SoC management apparatus using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention.

의 크기로 충방전을 제어하는 ESS 충방전 제어부(37)와, 제 3 SOC 비교부(35)에서 현재 SOC 값이 SOC 제어 불감대 영역 하한선(SOC_L1)과 SOC 제어 불감대 영역 상한선(SOC_H1) 사이에 위치하면 ESS 충방전값을 0(P_ESS=0)으로 변경하는 ESS 충방전값 변경부(38)를 포함한다.The SoC management device using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention measures the frequency (f) of the SOC and the power system in the corresponding section, and measures the frequency control deadband upper limit (f _H ) and the measurement frequency. (f) If the measured frequency (f) in the first system frequency comparison unit 31 and the first system frequency comparison unit 31 to compare (f) does _{not exceed the upper limit of the frequency control deadband area (f H} ), the frequency control deadband In the second system frequency comparison unit 32 for comparing the region lower limit line f _L and the measurement frequency f, and the first system frequency comparison unit 31, the measurement frequency f is the upper limit of the frequency control deadband region f _{If H} ) is exceeded, the measured frequency f is the frequency control deadband in the first SOC comparison unit 33 and the second system frequency comparison unit 32 comparing the current SOC value and the SOC overcharge prevention mode division line (SOC _{H2 ).} If the range lower limit (f _L ) is not exceeded, the measurement frequency f in the second SOC comparison unit 34 and the second system frequency comparison unit 32 that compares the current SOC value and the overdischarge prevention mode division line SOC _L2 If is not less than the frequency control deadband region lower limit (f _L ), the current SOC value is located between the SOC control deadband region lower limit (SOC _L1 ) and the SOC control deadband region upper limit (SOC _H1 ). (35) And, the current SOC value in the first SOC comparison unit 33 _{is greater than the SOC overcharge prevention mode division line (SOC H2} ), or the current SOC value in the second SOC comparison unit 34 is the overdischarge prevention mode division line ( If the _{current SOC value is less than SOC L2} ) or is not located between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ) in the third SOC comparison unit 35, the adaptive control method is used. In the adaptive droop control unit 36 that manages SoC by changing the droop slope, and the first SOC comparison unit 33, the current SOC value is set to prevent SOC overcharging. De or more than the dividing line (SOC _H2) in the current SOC value SOC 2 comparison part 34 is more than the anti-over-discharge mode, divider (SOC _L2)

The current SOC value in the ESS charge/discharge control unit 37 that controls charging and discharging with the size of the SOC control unit 35 is the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1). ), it includes an ESS charge/discharge value change unit 38 that changes the ESS charge/discharge value to 0 (P _{ESS = 0).}

4 is a state diagram of SoC management and control of the power generation-linked ESS according to the present invention.

In FIG. 4, the current SOC value in the first SOC comparison unit 33 _{is greater than the SOC overcharge prevention mode division line SOC H2} , or the current SOC in the second SOC comparison unit 34 in FIG. The value is less than the overdischarge prevention mode division line (SOC _L2 ), or the current SOC value in the third SOC comparison unit 35 is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ). If it is not located at, it is an adaptive droop control section in which SoC management is performed by changing the droop slope in an adaptive control method.

의 크기로 충전을 하는 영역이고, (라) 영역은 현재 SOC 값이 과방전 방지 모드 구분선(SOC_L2)을 넘으면

의 크기로 방전을 제어하는 영역이다.
여기서, △P는 전력 변동값, △f는 변동 주파수, R은 드룹(Droop) 기울기이다.And in FIG. 4, the (C) area is when the current SOC value does not exceed the _{SOC overcharge prevention mode division line (SOC H2).}

It is an area that is charged with the size of and (D) area is when the current SOC value exceeds the overdischarge prevention mode division line (SOC _L2 ).

It is an area that controls the discharge by the size of.
Here, ΔP is the power fluctuation value, Δf is the fluctuation frequency, and R is the droop slope.

5 is a graph showing a droop slope changing method according to the present invention.

으로 이루어진다.The droop slope change according to the present invention depends on the change of Δf and SOC

It consists of.

6 is a block diagram of an SoC management control unit of a power generation-linked ESS according to the present invention.

The SOC change unit 61 that outputs ΔSOC by changing the power to SOC for SoC management by changing the droop slope in an adaptive control method, and changing the ΔSOC value to the K _D value for frequency feedback of the SOC. The SOC value conversion unit 62 that outputs the converted SOC value (K _R ) by changing using the coefficient K _R , and the variable frequency (Δf) and the coefficient K _{R of the SOC value conversion unit 62 are used.} It includes a P _SOC output unit 63 _{for outputting power P SOC} for managing SOC by controlling the change of droop slope _R as an input of the converted SOC value K R.

Here, P _SOC and ΔSOC are defined as follows.

여기서, K_D는 드룹 계수에 해당하는 부분(1/R)이다.

Here, K _D is a part (1/R) corresponding to the droop coefficient.

여기서, K_E는 ESS의 용량의 에너지 표현[MWs], s는 라플라스 연산자이다.

Here, K _E is the energy expression of the capacity of the ESS [MWs], and s is the Laplace operator.

The operation characteristics in FIG. 6 are summarized in Table 1.

Droop gradient change control (K _D ) may be performed as follows.

인 경우에서,

이면

이고,

이면,

으로 정의된다.

In the case of,

Back side

ego,

If,

Is defined as

인 경우에서

이면

이고,

이면

으로 정의된다.

In case

Back side

ego,

Back side

Is defined as

The SoC management method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention will be described in detail as follows.

7 is a flow chart showing a SoC management method using frequency tracking control and adaptive control of a power generation-linked ESS according to the present invention.

First, the SOC of the corresponding section and the frequency (f) of the power system are measured (S701), _{and a first system frequency comparison step of comparing the upper limit of the frequency control deadband region (f H} ) and the measurement frequency (f) is performed. .(S702)

_{Then, if the measurement frequency (f) does not exceed the frequency control deadband upper limit (f H} ) in the first system frequency comparison step, the second system compares the frequency control deadband region lower limit (f _L ) and the measurement frequency (f). The frequency comparison step is performed (S703).

And if the measurement frequency (f) exceeds the upper limit of the frequency control deadband area (f _H ) in the first system frequency comparison step, a first SOC comparison step of comparing the current SOC value with the SOC overcharge prevention mode division line (SOC _{H2) is performed.} .(S704)

Next, in the second system frequency comparison step, if the measurement frequency (f) does _{not exceed the lower limit of the frequency control deadband region (f L} ), a second SOC comparison step of comparing the current SOC value and the overdischarge prevention mode division line (SOC _{L2) is performed.} Perform. (S705)

And in the second system frequency comparison step, if the measured frequency (f) _{is not less than the frequency control deadband lower limit (f L} ), the current SOC value is the SOC control deadband lower limit (SOC _L1 ) and the SOC control deadband upper limit (SOC). _H1 ) performs a third SOC comparison step of determining whether it is located between (S706)

If, in the first SOC comparison step, the current SOC value is _{greater than the SOC overcharge prevention mode dividing line (SOC H2} ), or in the second SOC comparison step, the current SOC value is _{less than the overdischarge prevention mode dividing line (SOC L2} ), or the third In the SOC comparison stage, if the current SOC value is _{not located between the lower limit of the SOC control deadband area (SOC L1} ) and the upper limit of the SOC control deadband area (SOC _H1 ), the SoC management is performed by changing the drop slope in an adaptive control method. The adaptive droop control step is performed (S707).

의 크기로 충방전을 제어하는 ESS 충방전 제어 단계를 수행한다.(S708)And if the current SOC value does not exceed the SOC overcharge prevention mode divider line (SOC _H2 ) in the first SOC comparison step, or the current SOC value exceeds the overdischarge prevention mode divider line (SOC _L2 ) in the second SOC comparison step.

The ESS charge/discharge control step of controlling charge/discharge with the size of is performed (S708).

And in the third SOC comparison step, if the current SOC value is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ), the ESS charge/discharge value _{is changed to 0 (P ESS} = 0). The ESS charging/discharging value changing step is performed (S709).

By repeating this process, charging and discharging in a predetermined section is completed (S710), and waits until the next cycle (S710).

In the SoC management apparatus and method using the frequency tracking control and adaptive control of the power generation-linked ESS according to the present invention described above, when the power system frequency fluctuates, the ESS (Energy Storage System) controls the frequency according to the droop slope. It is to change the slope, reduce the charge/discharge value of ESS, and manage the SoC.

In particular, the present invention is connected to a generator to control droop for power system frequency correction, and when charging or discharging, and then reducing the power value of the ESS, the charging/discharging value is drooped in an adaptive control method instead of changing to 0. (Droop) It relates to SoC management using frequency tracking control and adaptive control of power generation-linked ESS that gradually changes the slope.

As described above, it will be understood that the present invention is implemented in a modified form without departing from the essential characteristics of the present invention.

Therefore, the specified embodiments should be considered from a descriptive point of view rather than a limiting point of view, and the scope of the present invention is shown in the claims rather than the above description, and all differences within the scope equivalent thereto are included in the present invention. It will have to be interpreted.

100. Electrical Network
200. Power generation control unit
300. ESS
400. Development Department
500. Power system stabilization unit

Claims (15)

A power generation control unit that senses a change in a frequency of a power system according to a change in output or a load of a generator through an electrical network, and performs automatic power generation control and speed control;
An ESS that is linked to the power generation control unit and a generator to manage the SoC by controlling the frequency while changing the slope according to the droop slope when the power system frequency fluctuates and reducing the charge/discharge value of the ESS;
Including; a power generation unit having a generator that generates power by adjusting the power generation power so that the frequency of the power system maintains the rated frequency through valve control and turbine control, or through auxiliary adjustment of load increase or decrease,
_{The ESS is the first system that compares the frequency control deadband upper limit (f H} ) and the measurement frequency (f) by measuring the frequency (f) of the SOC and the power system in the corresponding section for frequency tracking control and adaptive control. In the frequency comparison unit and the first system frequency comparison unit, if the measurement frequency (f) does _{not exceed the upper limit of the frequency control deadband area (f H} ), the frequency control deadband area lower limit (f _L ) and the measurement frequency (f) are compared. In the second system frequency comparison unit and the first system frequency comparison unit, when the measurement frequency (f) _{exceeds the upper limit of the frequency control deadband area (f H} ), the current SOC value is compared with the SOC overcharge prevention mode division line (SOC _{H2 ).} 1 In the SOC comparison unit and the second system frequency comparison unit, if the measured frequency (f) does _{not exceed the lower limit of the frequency control deadband area (f L} ), the second compares the current SOC value with the overdischarge prevention mode division line (SOC _{L2 ).} In the SOC comparison unit and the second system frequency comparison unit, if the measurement frequency (f) _{is not less than the frequency control deadband region lower limit (f L} ), the current SOC value is the SOC control deadband region lower limit (SOC _L1 ) and the SOC control deadband. SoC management apparatus using the frequency tracking control and adaptive control of the power generation-linked ESS, characterized in that it comprises a third SOC comparison unit for determining whether the region is located between the upper limit (SOC _H1). The frequency tracking control of the power generation-linked ESS according to claim 1, wherein the ESS and the power generation unit communicate with each other in the process of frequency tracking control and adaptive control to perform cooperative control, so that the generator and the ESS share the role of frequency control. SoC management device using adaptive control. The method of claim 1, wherein the ESS performs droop control and gradually decreases the droop slope in an adaptive control method instead of changing the charge/discharge value to 0 when reducing the power value of the ESS after charging or discharging. SoC management device using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that the SoC is managed by changing. The method of claim 3, wherein the ESS performs frequency control according to a droop slope and then changes the slope, reduces the charge/discharge value of the ESS, and manages the SoC,
SoC management device using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that the ESS reduces the charge/discharge value and at the same time changes the power supply from the generator. delete The method of claim 1, wherein a current SOC value in the first SOC comparison unit is greater than an _{SOC overcharge prevention mode division line (SOC H2), or}
In the second SOC comparison unit, the current SOC value is less than the _{overdischarge prevention mode division line (SOC L2 ), or}
In the 3rd SOC comparison unit, if the current SOC value is _{not located between the lower limit of the SOC control deadband area (SOC L1} ) and the upper limit of the SOC control deadband area (SOC _H1 ), the SoC is managed by changing the droop slope using an adaptive control method. SoC management apparatus using the frequency tracking control and adaptive control of the power generation-linked ESS, characterized in that it further comprises an adaptive droop control unit to perform. The method of claim 1, wherein the current SOC value in the first SOC comparison unit does not exceed an _{SOC overcharge prevention mode division line (SOC H2),}
If the current SOC value in the second SOC comparison unit exceeds the overdischarge prevention mode division line (SOC _L2 ),

Further comprising an ESS charge/discharge control unit for controlling charge and discharge at the size of,
△P is a power fluctuation value, △f is a fluctuating frequency, and R is a droop slope. SoC management device using frequency tracking control and adaptive control of a power generation-linked ESS. The method of claim 1, wherein in the third SOC comparison unit, when the current SOC value is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ), the ESS charge/discharge value is 0 (P SoC management device using frequency tracking control and adaptive control of the power generation-linked ESS, characterized in that it further comprises an ESS charge/discharge value change unit that changes to _{ESS = 0).} A first system frequency comparison step of measuring the frequency (f) of the SOC and the power system and comparing the upper limit of the frequency control deadband region (f _{H) with the measurement frequency (f);}
In the first system frequency comparison step, if the measurement frequency (f) does _{not exceed the frequency control deadband upper limit (f H} ), the second system frequency comparison compares the frequency control deadband region lower limit (f _L ) and the measurement frequency (f). step;
A first SOC comparison step of comparing a current SOC value with a SOC overcharge prevention mode division line SOC _H2 when the measurement frequency f exceeds the frequency control deadband region upper limit f _{H in the first system frequency comparison step;}
A second SOC comparison step of comparing a current SOC value with an overdischarge prevention mode dividing line SOC _L2 if the measurement frequency f does not exceed the frequency control deadband region lower limit f _{L in the second system frequency comparison step;}
In the second system frequency comparison step, if the measured frequency (f) _{is not less than the frequency control deadband region lower limit (f L} ), the current SOC value is SOC control deadband region lower limit (SOC _L1 ) and the SOC control deadband region upper limit (SOC _H1). ); a third SOC comparison step of determining whether it is located between; and using frequency tracking control and adaptive control of a power generation-linked ESS, characterized in that SOC management is performed by changing a droop slope in an adaptive control method. SoC management method. The method of claim 9, wherein in the first SOC comparison step, a current SOC value is greater than an _{SOC overcharge prevention mode division line (SOC H2), or}
In the second SOC comparison step, the current SOC value is less than the _{overdischarge prevention mode division line (SOC L2 ), or}
In the third SOC comparison step, if the current SOC value is _{not located between the lower limit of the SOC control deadband area (SOC L1} ) and the upper limit of the SOC control deadband area (SOC _H1 ), manage the SoC by changing the droop slope using an adaptive control method. SoC management method using frequency tracking control and adaptive control of a power generation-linked ESS, characterized in that performing an adaptive droop control step to perform the adaptive droop control step. The method of claim 9, wherein in the first SOC comparison step, a current SOC value does not exceed an _{SOC overcharge prevention mode division line (SOC H2 ),}
In the second SOC comparison step, if the current SOC value exceeds the overdischarge prevention mode division line (SOC _L2 ),

ESS charge/discharge control step of controlling charge and discharge with the size of
△P is the power fluctuation value, △f is the fluctuating frequency, and R is a droop slope. SoC management method using frequency tracking control and adaptive control of a power generation-linked ESS. The method of claim 9, wherein in the third SOC comparison step, when the current SOC value is between the lower limit of the SOC control deadband area (SOC _L1 ) and the upper limit of the SOC control deadband area (SOC _H1 ), the ESS charge/discharge value is 0 (P). SoC management method using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that the step of changing the ESS charge/discharge value to change to _{ESS = 0) is performed.} The method of claim 9, wherein in order to manage SOC by changing a droop slope in an adaptive control method,
SOC change step of changing the power to SOC and outputting a ΔSOC value,
An SOC value conversion step of outputting a converted SOC value (K _R ) by changing the ΔSOC value to a K _D value for frequency feedback using a coefficient (K _{R );}
Fluctuation frequency (Δf) and a coefficient (K _R) for using converted SOC value (K _R) the input to the P _SOC that by the Droop (Droop) Tilt (R) changes the control output power (P _SOC) for managing SOC SoC management method using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that it includes an output step, and K _{D is a part (1/R) corresponding to a droop coefficient.} The method of claim 13, wherein P _SOC and ΔSOC are

And,

SoC management method using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that K _E is the energy expression of the capacity of the ESS [MWs], and s is the Laplace operator. The method of claim 13, wherein the droop gradient change control (K _D ),

In the case of,

Back side

ego,

If,

Is defined as,

In case

Back side

ego,

Back side

SoC management method using frequency tracking control and adaptive control of power generation-linked ESS, characterized in that it is defined as.

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