KR102226008B1 - Apparatus for controlling voltage of electric power system and method thereof - Google Patents

Abstract

An apparatus and a method for controlling a voltage of a power system according to an embodiment are disclosed. The method for controlling the voltage of the power system includes obtaining data including the magnitudes and phases of voltages and currents for all buses of the power system; Calculating an electric current based on the acquired data; Identifying a bus that violates a preset constraint based on the calculated power current; And removing the constraint violation by calculating a correction amount of the state constraint variable of the system and updating the state constraint variable based on the calculated correction amount of the state constraint variable when the bus line in violation of the constraint is identified. do.

Description

Device for controlling the voltage of the power system and its method {APPARATUS FOR CONTROLLING VOLTAGE OF ELECTRIC POWER SYSTEM AND METHOD THEREOF}

The embodiments relate to a voltage control technique, and more particularly, to an apparatus and a method for controlling a voltage of a power system.

In general, the state in which the power system operates stably refers to a state in which the voltage and frequency are maintained within the specified allowable range at a certain point in the system, and each active power and reactive power are balanced.

However, as the grid connection of the distributed power supply increases and the system becomes more complex, the voltage violation of the power system busbar such as low voltage and high voltage increases, and the likelihood of system accidents is also increasing. Accordingly, the necessity of voltage control for voltage stabilization has emerged.

Registered Patent Publication No. 10-1039426 Registered Patent Publication No. 10-1659312

The embodiment may provide an apparatus and method for controlling the voltage of a power system.

A method for controlling a voltage of a power system according to an embodiment of the present invention includes obtaining data including magnitudes and phases of voltages and currents for all buses of the power system; Calculating an electric current based on the acquired data; Identifying a bus that violates a preset constraint based on the calculated power current; And removing the constraint violation by calculating a correction amount of the state constraint variable of the system and updating the state constraint variable based on the calculated correction amount of the state constraint variable when the bus line in violation of the constraint is identified. can do.

In the calculating step, the power current may be calculated using a newton-raphson method based on the acquired data.

In the verifying step, a bus that is out of a predetermined restriction violation range is checked based on the calculated power current, and the restriction violation range is a violation range determined for the reactive power of the generating bus and the voltage of the bus excluding the generating bus. I can.

을 이용하여 전압 수정량 Δv과 발전 모선의 무효전력 수정량 ΔQGen을 산출하되, 행렬 J는 decoupled voltage jacobian matrix이고, 행렬 A는 발전 모선에서의 decoupled voltage jacobian matrix이고, 행렬 B, C는 모선에서의 decoupled voltage jacobian matrix이고, ΔQ는 무효전력 수정량을 나타내고, ΔQGen은 발전 모선의 무효전력 수정량이고, 상기 산출된 전압 수정량 Δv과 제어 수정량 Δcontrol을 기초로 상기 계통의 상태 제약변수의 수정량을 산출할 수 있다.In the removing step (Equation 1)

Calculate the voltage correction amount Δv and the reactive power correction amount ΔQGen of the generating bus using, but matrix J is the decoupled voltage jacobian matrix, matrix A is the decoupled voltage jacobian matrix in the generating bus, and matrices B and C are is the decoupled voltage jacobian matrix, ΔQ represents the reactive power correction amount, ΔQGen is the reactive power correction amount of the generating bus, and the correction amount of the state constraint variable of the system based on the calculated voltage correction amount Δv and the control correction amount Δcontrol Can be calculated.

The voltage correction amount Δv is calculated by (Equation 2) JΔv = ΔQ-AΔcontrol derived from (Equation 1), and the reactive power correction amount ΔQ = 0.

에 의해 산출될 수 있다.The reactive power correction amount ΔQGen of the power generation bus is derived from (Equation 1) above (Equation 3)

Can be calculated by

에 의해 산출될 수 있다.The correction amount Δconstraint of the state constraint variable of the system is (Equation 4)

Can be calculated by

In the removing step, it is checked whether the calculated voltage correction amount and the reactive power correction amount of the power generation bus are '0', and the calculated correction amount of the bus voltage and the reactive power correction amount of the power generation bus line is '0'. If not, the correction amount of the state constraint variable of the system may be calculated based on the calculated voltage correction amount and the control correction amount.

An apparatus for controlling a voltage of a power system according to another embodiment of the present invention includes a data acquisition unit for acquiring data including magnitudes and phases of voltages and currents for all bus lines of the power system; A power flow calculator that calculates an electric current based on the acquired data; A restriction violation confirmation unit that checks a bus that violates a preset restriction based on the calculated power current; And when the bus in violation of the constraint is identified, a correction amount of the state constraint variable of the system is calculated, and the state constraint variable is updated based on the calculated amount of the state constraint variable to remove the constraint violation. May contain wealth.

The power current calculator may calculate the power current using a newton-raphson method based on the acquired data.

The restriction violation confirmation unit checks a bus that is out of a predetermined restriction violation range based on the calculated power current, and the restriction violation range is a defined violation range for the reactive power of the generating bus and the voltage of the bus excluding the generating bus. I can.

을 이용하여 전압 수정량 Δv과 발전 모선의 무효전력 수정량 ΔQGen을 산출하되, 행렬 J는 decoupled voltage jacobian matrix이고, 행렬 A는 발전 모선에서의 decoupled voltage jacobian matrix이고, 행렬 B, C는 모선에서의 decoupled voltage jacobian matrix이고, ΔQ는 무효전력 수정량을 나타내고, ΔQGen은 발전 모선의 무효전력 수정량이고, 상기 산출된 전압 수정량 Δv과 제어 수정량 Δcontrol을 기초로 상기 계통의 상태 제약변수의 수정량을 산출할 수 있다.The restriction violation removal unit (Equation 1)

Calculate the voltage correction amount Δv and the reactive power correction amount ΔQGen of the generating bus using, but matrix J is the decoupled voltage jacobian matrix, matrix A is the decoupled voltage jacobian matrix in the generating bus, and matrices B and C are is the decoupled voltage jacobian matrix, ΔQ represents the reactive power correction amount, ΔQGen is the reactive power correction amount of the generating bus, and the correction amount of the state constraint variable of the system based on the calculated voltage correction amount Δv and the control correction amount Δcontrol Can be calculated.

The voltage correction amount Δv is calculated by (Equation 2) JΔv = ΔQ-AΔcontrol derived from (Equation 1), and the reactive power correction amount ΔQ = 0.

에 의해 산출될 수 있다.The reactive power correction amount ΔQGen of the power generation bus is derived from (Equation 1) above (Equation 3)

Can be calculated by

에 의해 산출될 수 있다.The correction amount Δconstraint of the state constraint variable of the system is (Equation 4)

Can be calculated by

The restriction violation removal unit checks whether the calculated voltage correction amount and the reactive power correction amount of the power generation bus are '0', and the calculated correction amount of the voltage of the bus and the reactive power correction amount of the power generation bus is '0'. If not, the correction amount of the state constraint variable of the system may be calculated based on the calculated voltage correction amount and the control correction amount.

According to an embodiment, a bus voltage violation may be eliminated by using a reactive power control facility group desired by a system operator.

According to the embodiment, the generator and the SVC facility can also be controlled, and practical voltage control may be possible by operating the facility adjacent to the violating site due to the nature of the power system voltage.

1 is a diagram illustrating a method for controlling a voltage of a power system according to an embodiment of the present invention.
2A to 2B are diagrams for explaining a process of checking a restriction violation of FIG. 1.
3A to 3C are diagrams for explaining the shape of a decoupled voltage jacobian matrix.
4 is a diagram illustrating an apparatus for controlling a voltage of a power system according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

However, the technical idea of the present invention is not limited to some embodiments to be described, but may be implemented in various different forms, and within the scope of the technical idea of the present invention, one or more of the constituent elements may be selectively selected between the embodiments. It can be combined with and substituted for use.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention are generally understood by those of ordinary skill in the art, unless explicitly defined and described. It can be interpreted as a meaning, and terms generally used, such as terms defined in a dictionary, may be interpreted in consideration of the meaning in the context of the related technology.

In addition, terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention.

In the present specification, the singular form may also include the plural form unless specifically stated in the phrase, and when described as “at least one (or more than one) of A and (and) B and C”, it is combined with A, B, and C. It may contain one or more of all possible combinations.

In addition, terms such as first, second, A, B, (a), and (b) may be used in describing the constituent elements of the embodiment of the present invention.

These terms are only for distinguishing the component from other components, and are not limited to the nature, order, or order of the component by the term.

And, when a component is described as being'connected','coupled' or'connected' to another component, the component is not only directly connected, coupled, or connected to the other component, but also with the component. It may also include the case of being'connected','coupled' or'connected' due to another element between the other elements.

In addition, when it is described as being formed or disposed on the “top (top) or bottom (bottom)” of each component, the top (top) or bottom (bottom) is one as well as when the two components are in direct contact with each other. It also includes the case where the above other component is formed or disposed between the two components. In addition, when expressed as "upper (upper) or lower (lower)", the meaning of not only an upward direction but also a downward direction based on one component may be included.

In the embodiment, power currents are calculated based on the data acquired for all buses, and the buses that violate constraints are identified based on the calculated power currents, and then the correction amount of the state constraint variable of the system is calculated, and the calculated correction amount is based. We propose a new method to remove the constraint violation of the corresponding bus by updating the state constraint variable of the furnace system.

1 is a diagram illustrating a method for controlling a voltage of a power system according to an embodiment of the present invention.

Referring to FIG. 1, an apparatus for controlling a voltage of a power system according to an embodiment of the present invention (hereinafter, referred to as a control device) is first described in terms of voltage and current magnitudes for all buses, that is, power buses and other buses. , Data such as phase may be obtained (S100).

Next, the control device may calculate a load flow based on the acquired data. As an example, the control device may calculate the power current using a newton-raphson method based on the acquired data (S200).

At this time, the power flow using the Newton-Rapson method can be calculated using the following [Equation 1].

[Equation 1]

는 jacobian matrix를 나타내고, Δθ 는 전압의 위상차를 나타내고, Δv는 전압 수정량을 나타내고, Δp는 유효 전력의 차이를 나타내고, Δq는 무효전력의 차이를 나타낸다.here,

Denotes a jacobian matrix, Δθ denotes the phase difference of the voltage, Δv denotes the voltage correction amount, Δp denotes the difference in active power, and Δq denotes the difference in reactive power.

Next, the control device may check whether there is a bus in violation of the constraint based on the calculated power current (S300). Since the restriction refers to the reactive power of the power generation bus and other bus voltages, in the present invention, it is possible to confirm the violation of the reactive power of the power generation bus and other bus voltages out of the predetermined limit violation range based on the calculated power current. .

At this time, the system operator can determine the extent of the restriction violation to determine whether the restriction is violated.

2A to 2B are diagrams for explaining a process of checking a restriction violation of FIG. 1.

Referring to FIG. 2A, a screen in which a voltage violation range, that is, a lower limit value and an upper limit value, is set is shown. The grid operator may be able to adjust this set voltage violation range.

Referring to FIG. 2B, buses outside the range set in FIG. 2A can be identified after calculating the power current.

Here, the case of setting the voltage violation range and checking the violation busses is described, but the same applies to setting the reactive power violation range of the generating bus and checking the violation buses.

Next, the control device may remove the violation of the constraint of the confirmed bus (S400). That is, the control device calculates the correction amount of the system state constraint variable based on the correction amount of the voltage of the bus and the amount of reactive power of the generating bus, and updates the state constraint variable of the system based on the calculated correction amount. The breach of constraints on the mothership for which the breach has been identified can be eliminated.

Specifically, the control device may calculate the correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus (S410).

At this time, the constraint violation removal equation is as follows [Equation 2].

[Equation 2]

을 나타낸다. 이때, decoupled jacobian matrix는 다음의 [수학식 3]과 같다.Here, matrix J is a simplified jacobian matrix using PQ decoupling, decoupled voltage jacobian matrix =

Represents. At this time, the decoupled jacobian matrix is as shown in [Equation 3] below.

[Equation 3]

Matrices A, B, and C are matrices related to the control of the reactive power control facility, Δv represents the voltage correction amount, Δcontrol represents the correction amount of the reactive power control facility, ΔQ represents the reactive power correction amount, and ΔQGen represents the power generation Shows the amount of reactive power correction of the bus.

3A to 3C are diagrams for explaining the shape of a decoupled voltage jacobian matrix.

의 구성 형태를 보여주고 있다. 무효전력 제어설비인 발전기(generator), 동기조상기(SVC, Static Var Compensator), 션트 리액터/커패시터(shunt reactor/capacitor), 변압기 탭(Transformer Tap)의 투입에 따라 구성 형태가 달라질 수 있다.Referring to Figure 3a, in the above [Equation 2]

It shows the configuration form of. The configuration type may vary depending on the input of a reactive power control facility such as a generator, a static var compensator (SVC), a shunt reactor/capacitor, and a transformer tap.

는 행렬 J만을 포함하는 형태가 된다.Referring to FIG. 3B, when there are n buses, the form of a decoupled voltage jacobian matrix is shown. in this case

Becomes a form containing only the matrix J.

는 행렬 J, A, B, C를 포함하게 된다.Referring to FIG. 3C, when a shunt is input to bus 2, a transformer is input between bus 1 and bus 5, and bus 5 is a power generation bus, the form of a decoupled voltage jacobian matrix is shown. in this case

Contains matrices J, A, B, and C.

, 행렬 B, C는

가 된다.At this time, when controlling the generator in the bus i, the bus i is the power generation bus, and if it is connected to the bus k, the matrix A is

, Matrices B, C are

Becomes.

When controlling the SVC and shunt in the bus i, the entry value of the matrix A becomes'-1' when input and '0' when open.

(at the tap size bus),

(the other transformer bus)와 같이 두 개의 값을 갖고, a는 권선비를 나타낸다.When controlling the transformer tap on bus i, matrix A is

(at the tap size bus),

It has two values like (the other transformer bus), where a represents the turns ratio.

From the above [Equation 2], the following [Equation 4] and [Equation 5] can be obtained, respectively.

[Equation 4]

JΔv + AΔcontrol = ΔQ

JΔv = ΔQ-AΔcontrol

[Equation 5]

In the above [Equation 2], in the process of removing the violation, ΔQ of a bus that is not a power generation bus is fixed to 0. Therefore, if ΔQ = 0, that is, when the change in MVAR (Mega Voltage Ampere Reactive) is set to 0, the above [Equation 4] can be expressed again as in [Equation 6] below.

[Equation 6]

JΔv =-AΔcontrol

In this case, [Equation 6] may be used to calculate the voltage correction amount Δv for all buses by using the control correction amount Δcontrol.

In addition, the [Equation 5] may be used to calculate the reactive power correction amount ΔQGen of the power generation bus using the voltage correction amount Δv and the control correction amount Δcontrol obtained from the [Equation 6].

The control device may check whether the correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus obtained through [Equation 5] and [Equation 6] is '0' or within a predetermined violation elimination range (S420). ). Here, a case where '0' is not satisfied will be described as an example.

When the correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus are not '0', the control device may calculate the correction amount of the state constraint variable of the system (S430).

The correction amount Δconstraint of the state constraint variable of the system according to the obtained correction amount of the voltage of the bus bar and the correction amount of the reactive power of the generating bus can be expressed as the following [Equation 7].

[Equation 7]

When [Equation 6] is substituted into [Equation 7], the correction amount Δconstraint of the state constraint variable of the system can be expressed as the control correction amount Δcontrol, as follows [Equation 8].

[Equation 8]

는 발전 모선을 제외한 그 외의 모선의 전압인 경우 해당 모선은 1.0, 그 이외의 모선은 0.0이 되고, 발전 모선의 무효전력인 경우 행렬 B, C의 값

이 된다.here,

Is the value of the matrix B and C in case of the voltage of other buses excluding the generating bus, and 0.0 for the other buses, and in the case of reactive power of the generating bus.

Becomes.

The control device may remove the constraint violation of the bus by updating the state constraint variable of the system using the correction amount Δconstraint of the state constraint variable of the system (S440).

On the other hand, when the correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus is '0', the control device may determine that the violation of the proposal has been removed, and may end all processes.

In this way, in the present invention, the restriction violation removal process may be repeatedly performed until the correction amount of the voltage of the bus and the correction amount of the reactive power of the power generation bus is '0' or within the violation removal range.

4 is a diagram illustrating an apparatus for controlling a voltage of a power system according to an embodiment of the present invention.

Referring to FIG. 4, the apparatus for controlling the voltage of the power system according to an embodiment of the present invention includes a data acquisition unit 100, a power flow calculation unit 200, a restriction violation confirmation unit 300, and a restriction violation agent. It may include a rejection 400.

The data acquisition unit 100 may acquire data such as magnitudes and phases of voltages and currents for all buses, that is, power buses and other buses.

The power flow calculation unit 200 may calculate a load flow based on the acquired data. As an example, the power current calculator 200 may calculate the power current using a newton-raphson method based on the acquired data.

The constraint violation confirmation unit 300 may check a bus that violates the constraint based on the calculated power current. That is, the restriction violation confirmation unit 300 may check the reactive power of the power generation bus and the violation of other bus voltages outside the predetermined restriction violation range based on the calculated power current.

The restriction violation removal unit 400 may remove the restriction violation of the mother ship in which the restriction violation has been confirmed. That is, the restriction violation removal unit 400 may remove the restriction violation of the corresponding mothership when it is confirmed that the mothership violating the restriction is identified.

Specifically, when the constraint violation removing unit 400 is identified, the constraint violation removing unit 400 first determines the voltage correction amount using the constraint violation elimination equation when the constraint violating bus is identified. It is possible to calculate the correction amount of reactive power of the over-generation bus.

Next, the restriction violation removing unit 400 may check whether the calculated voltage correction amount and the reactive power correction amount of the power generation bus are '0' or within a predetermined violation elimination range.

Next, the constraint violation removal unit 400, when the calculated correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus is not '0', the state of the system based on the calculated voltage correction amount and the control correction amount. You can calculate the amount of correction for the constraint variable.

Next, the constraint violation removal unit 400 may remove the constraint violation of the corresponding bus by updating the state constraint variable of the system based on the calculated correction amount of the state constraint variable.

On the other hand, the restriction violation removal unit 400 determines that the proposed violation has been removed when the calculated correction amount of the voltage of the bus and the correction amount of the reactive power of the power generation bus is '0', and ends all processes.

The term'~ unit' used in this embodiment refers to software or hardware components such as field-programmable gate array (FPGA) or ASIC, and'~ unit' performs certain roles. However,'~ part' is not limited to software or hardware. The'~ unit' may be configured to be in an addressable storage medium, or may be configured to reproduce one or more processors. Thus, as an example,'~ unit' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, database, data structures, tables, arrays, and variables. Components and functions provided in the'~ units' may be combined into a smaller number of elements and'~ units', or may be further separated into additional elements and'~ units'. In addition, components and'~ units' may be implemented to play one or more CPUs in a device or a security multimedia card.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. You will understand that you can do it.

100: data acquisition unit
200: power flow calculation unit
300: Pharmaceutical Violation Confirmation Department
400: restriction violation removal unit

Claims (16)

Acquiring data including magnitudes and phases of voltages and currents for all buses of the power system;
Calculating an electric current based on the acquired data;
Identifying a bus that violates a preset constraint based on the calculated power current; And
When it is confirmed that the mothership violating the constraint, calculating a correction amount of the state constraint variable of the system and removing the constraint violation by updating the state constraint variable based on the calculated correction amount of the state constraint variable, and ,
In the removing step,
(Equation 1)

Calculate the voltage correction amount Δv and the reactive power correction amount ΔQGen of the generating bus using, but matrix J is the decoupled voltage jacobian matrix, matrix A is the decoupled voltage jacobian matrix in the generating bus, and matrices B and C are decoupled voltage jacobian matrix, ΔQ represents the correction amount of reactive power, ΔQGen is the correction amount of reactive power of the generating bus,
A method for controlling a voltage of a power system, calculating a correction amount of the state constraint variable of the system based on the calculated voltage correction amount Δv and a control correction amount Δcontrol. The method of claim 1,
In the calculating step,
A method for controlling a voltage of a power system, calculating the power current using a newton-raphson method based on the acquired data. The method of claim 1,
In the step of confirming,
Based on the calculated electric current, check buses that are outside the range of violations of the predetermined restrictions,
The restriction violation range is a violation range determined for the reactive power of the power generation bus and the voltage of the bus excluding the power generation bus. delete The method of claim 1,
The voltage correction amount Δv is calculated by (Equation 2) JΔv = ΔQ-AΔcontrol derived from (Equation 1), and the reactive power correction amount ΔQ = 0, a method for controlling a voltage of a power system. The method of claim 5,
The reactive power correction amount ΔQGen of the power generation bus is derived from (Equation 1) above (Equation 3)

A method for controlling the voltage of the power system, calculated by. The method of claim 1,
The correction amount Δconstraint of the state constraint variable of the system is (Equation 4)

A method for controlling the voltage of the power system, calculated by. The method of claim 7,
In the removing step,
Check whether the calculated voltage correction amount and the reactive power correction amount of the power generation bus are '0',
When the calculated correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus are not '0', the correction amount of the state constraint variable of the system is determined based on the calculated voltage correction amount and the control correction amount. A method for controlling the voltage of the power system to calculate. A data acquisition unit that acquires data including magnitudes and phases of voltages and currents for all bus lines of the power system;
A power flow calculator that calculates an electric current based on the acquired data;
A restriction violation confirmation unit that checks a bus that violates a preset restriction based on the calculated power current; And
When a bus in violation of the constraint is identified, a constraint violation removal unit that calculates a correction amount of the state constraint variable of the system and updates the state constraint variable based on the calculated correction amount of the state constraint variable to remove the constraint violation Including,
The restriction violation removal unit,
(Equation 1)

Calculate the voltage correction amount Δv and the reactive power correction amount ΔQGen of the generating bus using, but matrix J is the decoupled voltage jacobian matrix, matrix A is the decoupled voltage jacobian matrix in the generating bus, and matrices B and C are decoupled voltage jacobian matrix, ΔQ represents the correction amount of reactive power, ΔQGen is the correction amount of reactive power of the generating bus,
An apparatus for controlling a voltage of a power system, calculating a correction amount of a state constraint variable of the system based on the calculated voltage correction amount Δv and a control correction amount Δcontrol. The method of claim 9,
The power flow calculation unit,
An apparatus for controlling a voltage of a power system, calculating the power current using a Newton-raphson method based on the acquired data. The method of claim 9,
The restriction violation confirmation unit,
Based on the calculated electric current, check buses that are outside the range of violations of the predetermined restrictions,
The restriction violation range is a violation range determined with respect to the reactive power of the power generation bus and the voltage of the bus excluding the power generation bus. delete The method of claim 9,
The voltage correction amount Δv is calculated by (Equation 2) JΔv = ΔQ-AΔcontrol derived from (Equation 1), and the reactive power correction amount ΔQ = 0, a device for controlling the voltage of the power system. The method of claim 13,
The reactive power correction amount ΔQGen of the power generation bus is derived from (Equation 1) above (Equation 3)

A device for controlling the voltage of the power system, calculated by. The method of claim 9,
The correction amount Δconstraint of the state constraint variable of the system is (Equation 4)

A device for controlling the voltage of the power system, calculated by. The method of claim 15,
The restriction violation removal unit,
Check whether the calculated voltage correction amount and the reactive power correction amount of the power generation bus are '0',
When the calculated correction amount of the voltage of the bus and the correction amount of the reactive power of the generating bus are not '0', the correction amount of the state constraint variable of the system is determined based on the calculated voltage correction amount and the control correction amount. A device for controlling the voltage of the power system to be calculated.

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