JPH06161576A - Controller for reactive power compensator - Google Patents
Controller for reactive power compensatorInfo
- Publication number
- JPH06161576A JPH06161576A JP4338119A JP33811992A JPH06161576A JP H06161576 A JPH06161576 A JP H06161576A JP 4338119 A JP4338119 A JP 4338119A JP 33811992 A JP33811992 A JP 33811992A JP H06161576 A JPH06161576 A JP H06161576A
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- reactive power
- voltage
- output
- coefficient
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/30—Reactive power compensation
Landscapes
- Supply And Distribution Of Alternating Current (AREA)
- Control Of Electrical Variables (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は電力系統の電圧変動を抑
制する無効電力補償装置の制御装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a controller for a reactive power compensator for suppressing voltage fluctuations in a power system.
【０００２】[0002]
【従来の技術】従来使用されている無効電力補償装置の
制御の一例を図６に示す。電力系統の電力源１に電力系
統の短絡容量に相当するインピーダンス２を介して設置
されている無効電力補償装置において、電力系統の電圧
を検出する電圧検出回路４と無効電力補償装置の出力電
流を検出する電流検出回路５を持ち、系統電圧の基準値
を設定する基準電圧設定回路８の出力と電圧検出回路の
出力から差分回路７（以下、第１の差分回路と称す）に
より電圧偏差を計算し、差分回路９（以下、第２の差分
回路と称す）により電圧偏差と係数回路６により電流検
出回路の出力に係数Ｘs を乗じた値を減算し、この値か
ら電力系統に出力すべき無効電力を演算する無効電力出
力決定演算回路10を持つ。図７はこのように構成された
従来の無効電力補償装置の定常状態での電圧−電流特性
である。同図において、電流Ｉが無効電力補償装置の出
力電流であり、Ｖref が基準電圧設定器で設定された値
であり、Ａ−Ｂ間の電圧−電流特性が無効電力制御に用
いられる制御範囲であり、その特性式は(1) で与えられ
る。 Ｖ＝Ｖref ＋Ｘs ・Ｉ ………………………………………(1) ただし、Ｘs は係数回路６で与えられる係数である。図
８に過渡特性を表す無効電力補償装置のブロック図を示
す。同図において、Ｘは系統の短絡容量に相当するイン
ピーダンスを表す。又、同図を簡略化したものを図９に
示す。図９から無効電力補償装置の過渡応答特性は伝達
関数 により決まり、系統の短絡容量に相当するインピーダン
スＸにより特性が変わることが分かる。2. Description of the Related Art FIG. 6 shows an example of control of a conventional reactive power compensator. In a reactive power compensator installed in a power source 1 of a power system via an impedance 2 corresponding to a short-circuit capacity of the power system, a voltage detection circuit 4 for detecting the voltage of the power system and an output current of the reactive power compensator are detected. A voltage deviation is calculated by a difference circuit 7 (hereinafter referred to as a first difference circuit) from the output of the reference voltage setting circuit 8 that sets the reference value of the system voltage and the output of the voltage detection circuit that has the current detection circuit 5 that detects the voltage. Then, the difference circuit 9 (hereinafter, referred to as a second difference circuit) subtracts a value obtained by multiplying the voltage deviation and the coefficient circuit 6 by the output of the current detection circuit by the coefficient Xs, and outputs the value to the power system from this value. It has a reactive power output determination calculation circuit 10 for calculating power. FIG. 7 shows the voltage-current characteristics in a steady state of the conventional reactive power compensator thus configured. In the figure, current I is the output current of the reactive power compensator, Vref is the value set by the reference voltage setting device, and the voltage-current characteristic between A and B is within the control range used for reactive power control. Yes, its characteristic formula is given by (1). V = Vref + Xs · I ……………………………… (1) where Xs is a coefficient given by the coefficient circuit 6. FIG. 8 shows a block diagram of a reactive power compensator showing a transient characteristic. In the figure, X represents the impedance corresponding to the short-circuit capacity of the system. Further, a simplified version of this figure is shown in FIG. From Fig. 9, the transient response characteristic of the reactive power compensator is the transfer function. It can be seen that the characteristics vary depending on the impedance X corresponding to the short-circuit capacity of the system.
【０００３】[0003]
【発明が解決しようとする課題】上記従来方法では予め
電力系統のある短絡容量に対して制御装置の係数Ｘs と
無効電力決定演算回路の定数を決めているため、系統の
短絡容量が変化した場合に制御系がハンチングを起こし
たり、不安定になったりする。本発明は上記事情に鑑み
てなされたものであり、電力系統の短絡容量が変化して
も制御を安定に保ち、かつ常に同様の過渡応答特性を有
する無効電力補償装置の制御装置を提供することを目的
としている。In the above-mentioned conventional method, since the coefficient Xs of the control device and the constant of the reactive power determining arithmetic circuit are determined in advance for a certain short-circuit capacity of the power system, when the short-circuit capacity of the system changes. The control system causes hunting or becomes unstable. The present invention has been made in view of the above circumstances, and provides a control device for a reactive power compensator that maintains stable control even when the short-circuit capacity of a power system changes and that always has similar transient response characteristics. It is an object.
【０００４】[0004]
【課題を解決するための手段】本発明は電力系統の電圧
を検出する電圧検出回路と、系統に出力する無効電力の
電流を検出する電流検出回路と、前記電流検出回路の出
力に係数を乗ずる係数回路と、系統電圧の基準値を設定
する基準電圧設定回路と、前記電圧検出回路の出力と前
記基準電圧設定回路の出力の差を求める第１の差分回路
と、前記第１の差分回路の出力と前記係数回路の出力を
減ずる第２の差分回路と、前記第２の差分回路の出力か
ら系統に出力する無効電力を決定する無効電力決定演算
回路を有する無効電力補償装置において、前記基準電圧
設定回路の設定値を調整する第１の調整器と、前記調整
器により基準電圧を変化させたことによる電圧と電流を
もとに電力系統の短絡容量を推定する推定回路と、前記
推定回路により推定した短絡容量から前記係数回路の係
数と前記無効電力決定演算回路の定数を調整する第２の
調整器を備えた。According to the present invention, a voltage detection circuit for detecting a voltage of a power system, a current detection circuit for detecting a current of reactive power output to the system, and an output of the current detection circuit are multiplied by a coefficient. A coefficient circuit, a reference voltage setting circuit for setting a reference value of a system voltage, a first difference circuit for obtaining a difference between the output of the voltage detection circuit and the output of the reference voltage setting circuit, and the first difference circuit. In the reactive power compensator having a second differential circuit that reduces the output and the output of the coefficient circuit, and a reactive power determination arithmetic circuit that determines the reactive power output from the output of the second differential circuit to the grid, the reference voltage A first regulator that adjusts the set value of the setting circuit, an estimation circuit that estimates the short-circuit capacity of the power system based on the voltage and current resulting from changing the reference voltage by the regulator, and the estimation circuit Guess From the short-circuit capacity with a second regulator for regulating the constant factor and the reactive power determining calculation circuit of said coefficient circuits.
【作用】上記手段により本発明の無効電力補償装置の制
御装置は、電力系統の短絡容量が変化した場合でも過渡
特性を表す伝達関数の利得と位相を一定に保ち、制御系
が不安定となることはなく、かつどのような短絡容量に
対しても同様の過渡特性を持つことを可能にした。With the above means, the control device of the reactive power compensating device of the present invention keeps the gain and phase of the transfer function showing the transient characteristics constant even when the short-circuit capacity of the power system changes, and the control system becomes unstable. It is possible to have similar transient characteristics for any short-circuit capacity.
【０００５】[0005]
【実施例】以下図面を参照して実施例を説明する。図１
は本発明による無効電力補償装置の制御装置の一実施例
の構成図である。図１において図６と同一部分について
は同一符号を付して説明を省略する。11は基準電圧を調
整する調整器（以下、第１の調整器と称す）、12は前記
第１の調整器によって基準電圧を変化させたときの電
流，電圧より系統の短絡容量に相当するインピーダンス
Ｘを推定する推定器、13は前記推定されたインピーダン
スから係数Ｘs と無効電力出力決定演算回路の係数とを
調整する調整器（以下、第２の調整器と称す）である。
その他の構成は図６と同様である。Embodiments will be described below with reference to the drawings. Figure 1
FIG. 1 is a configuration diagram of an embodiment of a controller for a reactive power compensator according to the present invention. In FIG. 1, the same parts as those in FIG. Reference numeral 11 is a regulator for adjusting the reference voltage (hereinafter referred to as the first regulator), and 12 is an impedance corresponding to the short-circuit capacity of the system based on the current and the voltage when the reference voltage is changed by the first regulator. An estimator 13 for estimating X is an adjuster (hereinafter, referred to as a second adjuster) that adjusts the coefficient Xs and the coefficient of the reactive power output determination arithmetic circuit from the estimated impedance.
Other configurations are the same as those in FIG.
【０００６】ここで、無効電力補償装置の定常状態での
電圧−電流特性と電力系統特性を図に書くと図２のよう
になる。図２において、(a) は現状の無効電力補償装置
の電圧−電流特性であり、式(3) で表される。 Ｖ＝Ｖref １＋Ｘs ・Ｉ ……………………………………(3) ただし、Ｖref １は現状の電圧基準値である。(b) は電
力系統の特性であり、式(4) で表される。 Ｖ＝Ｅo −ｘ・Ｉ ……………………………………………(4) このとき、電力系統の電圧，電流は(c) の平衡点にあ
り、電流検出回路と電圧検出回路により検出できる。
今、この平衡点(c) での電流，電圧を（Ｉ１，Ｖ１）と
する。(d) は第１の調整器11により電圧基準値を変化さ
せた場合の特性を表し、式(5) で表される。 Ｖ＝Ｖref ２＋Ｘs ・Ｉ ……………………………………(5) ただし、新しい電圧基準値をＶref ２とする。無効電力
補償装置の電圧−電流特性が(d) となったことで電流，
電圧の平衡点は(e) に移る。この点での電流，電圧を
（Ｉ２，Ｖ２）とする。この値も電流検出器，電圧検出
器により検出できる。FIG. 2 shows the voltage-current characteristics and power system characteristics of the reactive power compensator in the steady state. In FIG. 2, (a) is the voltage-current characteristic of the current reactive power compensator, which is expressed by equation (3). V = Vref 1 + Xs I (3) However, Vref 1 is the current voltage reference value. (b) is the characteristic of the power system and is expressed by equation (4). V = Eo −x · I ………………………………………… (4) At this time, the voltage and current of the power system are at the equilibrium point of (c) and the current detection circuit It can be detected by the voltage detection circuit.
Now, let the current and voltage at this equilibrium point (c) be (I1, V1). (d) represents the characteristic when the voltage reference value is changed by the first adjuster 11, and is expressed by the equation (5). V = Vref 2 + Xs I (5) However, a new voltage reference value is Vref 2. Since the voltage-current characteristic of the reactive power compensator becomes (d), the current,
The voltage equilibrium point moves to (e). The current and voltage at this point are (I2, V2). This value can also be detected by the current detector and voltage detector.
【０００７】推定器12では例えば、２つの平衡点（Ｉ
１，Ｖ１）と（Ｉ２，Ｖ２）から短絡容量に相当するイ
ンピーダンスＸは式(6) で推定できる。 過渡応答特性は図９のブロック図で表せる。電力系統の
短絡容量に相当するインピーダンスＸが変化しても過渡
応答特性を変えないためには、図９中の伝達関数 の利得と位相を一定に保てば良い。そのためには、例え
ば、無効電力出力決定演算回路の伝達関数Ｇ(s) の利得
Ｋと、それ以外の伝達関数ＧＫ(s) に分ければ、式(7)
は式(8) で表される。 したがって、第２の調整器13は電力系統の短絡容量に相
当するインピーダンスＸが変化した場合、式(9) ，(10)
が成り立つようにＸs とＫを調整すれば良い。 Ｘ・Ｋ＝一定 ………………………………………………(9) Ｘs ・Ｋ＝一定 ………………………………………………(10)In the estimator 12, for example, two equilibrium points (I
From (1, V1) and (I2, V2), the impedance X corresponding to the short-circuit capacity can be estimated by the equation (6). The transient response characteristic can be represented by the block diagram of FIG. In order not to change the transient response characteristics even if the impedance X corresponding to the short-circuit capacity of the power system changes, the transfer function in FIG. It suffices to keep the gain and phase of the constant. For that purpose, for example, if the gain K of the transfer function G (s) of the reactive power output determination arithmetic circuit and the other transfer function GK (s) are divided,
Is expressed by equation (8). Therefore, when the impedance X corresponding to the short-circuit capacity of the power system changes, the second adjuster 13 can be expressed by equations (9) and (10).
Adjust Xs and K so that X ・ K = constant ……………………………………………… (9) Xs ・ K = constant ……………………………………………… ( Ten)
【０００８】図３，図４，図５は本発明を用いた場合と
従来の方法での過渡応答特性とを比較したものである。
Ｖは電力系統の電圧を、Ｑは無効電力補償装置の出力無
効電力を表す。図３はある電力系統の短絡容量に対して
Ｘs 及びＧ(s) を設計した結果である。したがって、本
発明でも、従来方法でも、短絡容量がこの設計時と同じ
であれば、過渡応答特性は図３のようになる。図４は従
来の方法において短絡容量が１／１０になった場合の過
渡応答特性である。無効電力補償装置の応答はハンチン
グしている。図５は本発明により短絡容量が１／１０に
なったことを推定してＸs とＧ(s) を調整した結果とし
て、制御対象である系統電圧は短絡容量が変わる前と同
様の過渡応答特性を実現している。FIG. 3, FIG. 4 and FIG. 5 are comparisons between the case of using the present invention and the transient response characteristics of the conventional method.
V represents the voltage of the power system, and Q represents the output reactive power of the reactive power compensator. FIG. 3 shows the result of designing Xs and G (s) for the short-circuit capacity of a certain power system. Therefore, in both the present invention and the conventional method, if the short-circuit capacity is the same as that at the time of this design, the transient response characteristic becomes as shown in FIG. FIG. 4 shows transient response characteristics when the short-circuit capacity becomes 1/10 in the conventional method. The reactive power compensator response is hunting. FIG. 5 shows that, as a result of adjusting Xs and G (s) by estimating that the short-circuit capacity has become 1/10 according to the present invention, the system voltage to be controlled has the same transient response characteristic as that before the short-circuit capacity is changed. Has been realized.
【０００９】[0009]
【発明の効果】以上説明したように、本発明によれば系
統の短絡容量が変化したとき、短絡容量に相当するイン
ピーダンスを推定して設計の係数Ｘs とＧ(s) を調整す
るようにしたので、安定でかつ同様の過渡等特性を有す
る無効電力補償装置の制御装置を提供できる。As described above, according to the present invention, when the short-circuit capacity of the system changes, the impedance corresponding to the short-circuit capacity is estimated and the design coefficients Xs and G (s) are adjusted. Therefore, it is possible to provide a control device for a reactive power compensator which is stable and has similar transient characteristics.
【図１】本発明による無効電力補償装置の制御装置の一
実施例のブロック図。FIG. 1 is a block diagram of an embodiment of a controller for a reactive power compensator according to the present invention.
【図２】本発明による電圧−電流特性図。FIG. 2 is a voltage-current characteristic diagram according to the present invention.
【図３】本発明の作用を説明する過渡応答特性図。FIG. 3 is a transient response characteristic diagram illustrating the operation of the present invention.
【図４】本発明の作用を説明する過渡応答特性図。FIG. 4 is a transient response characteristic diagram illustrating the operation of the present invention.
【図５】本発明の作用を説明する過渡応答特性図。FIG. 5 is a transient response characteristic diagram illustrating the operation of the present invention.
【図６】従来の構成を示す説明図。FIG. 6 is an explanatory diagram showing a conventional configuration.
【図７】従来の構成の電圧−電流特性図。FIG. 7 is a voltage-current characteristic diagram of a conventional configuration.
【図８】無効電力補償装置の過渡特性説明用のブロック
図。FIG. 8 is a block diagram for explaining transient characteristics of a reactive power compensator.
【図９】無効電力補償装置の過渡特性説明用のブロック
図。FIG. 9 is a block diagram for explaining transient characteristics of a reactive power compensator.
１ 電力系統電源 ２ インピーダンス ３ 無効電力補償装置 ４ 電圧検出回路 ５ 電流検出回路 ６ 係数回路 ７，９ 差分回路 ８ 基準電圧設定回路 10 無効電力出力決定演算回路 11 第１の調整器 12 推定器 13 第２の調整器 1 Power system power supply 2 Impedance 3 Reactive power compensator 4 Voltage detection circuit 5 Current detection circuit 6 Coefficient circuit 7, 9 Difference circuit 8 Reference voltage setting circuit 10 Reactive power output determination arithmetic circuit 11 First regulator 12 Estimator 13 Number 2 regulators
Claims (1)
と、系統に出力する無効電力の電流を検出する電流検出
回路と、前記電流検出回路の出力に係数を乗ずる係数回
路と、系統電圧の基準値を設定する基準電圧設定回路
と、前記電圧検出回路の出力と前記基準電圧設定回路の
出力の差を求める第１の差分回路と、前記第１の差分回
路の出力と前記係数回路の出力を減ずる第２の差分回路
と、前記第２の差分回路の出力から系統に出力する無効
電力を決定する無効電力決定演算回路を有する無効電力
補償装置において、前記基準電圧設定回路の設定値を調
整する第１の調整器と、前記第１の調整器により基準電
圧を変化させたことによる電圧と電流とから電力系統の
短絡容量を推定する推定回路と、前記推定回路により推
定した短絡容量をもとに前記係数回路の係数と前記無効
電力決定演算回路の定数を調整する第２の調整器を備え
たことを特徴とする無効電力補償装置の制御装置。1. A voltage detection circuit for detecting a voltage of a power system, a current detection circuit for detecting a current of reactive power output to the system, a coefficient circuit for multiplying an output of the current detection circuit by a coefficient, and a system voltage A reference voltage setting circuit that sets a reference value, a first difference circuit that obtains a difference between the output of the voltage detection circuit and the output of the reference voltage setting circuit, and an output of the first difference circuit and an output of the coefficient circuit. In a reactive power compensating device having a second differential circuit that reduces the power consumption and a reactive power determination arithmetic circuit that determines the reactive power output from the output of the second differential circuit to the grid, and adjusts the set value of the reference voltage setting circuit. The first regulator, the estimation circuit that estimates the short-circuit capacity of the power system from the voltage and the current resulting from changing the reference voltage by the first regulator, and the short-circuit capacity that is estimated by the estimation circuit. When A control device for a reactive power compensator, further comprising a second adjuster for adjusting a coefficient of the coefficient circuit and a constant of the reactive power determination calculation circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4338119A JPH06161576A (en) | 1992-11-25 | 1992-11-25 | Controller for reactive power compensator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4338119A JPH06161576A (en) | 1992-11-25 | 1992-11-25 | Controller for reactive power compensator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06161576A true JPH06161576A (en) | 1994-06-07 |
Family
ID=18315093
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4338119A Pending JPH06161576A (en) | 1992-11-25 | 1992-11-25 | Controller for reactive power compensator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06161576A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102790396A (en) * | 2012-08-28 | 2012-11-21 | 贵州电网公司电力调度控制中心 | Voltage stabilization open-loop control method on basis of short circuit capacity |
| WO2013151154A1 (en) * | 2012-04-06 | 2013-10-10 | 株式会社 東芝 | Short-circuit capacity observation method for power grid, and system thereof |
| CN110163540A (en) * | 2019-06-28 | 2019-08-23 | 清华大学 | Electric power system transient stability prevention and control method and system |
| JP2019176715A (en) * | 2018-03-29 | 2019-10-10 | サングロー パワー サプライ カンパニー リミテッド | Method for suppressing voltage fluctuation in common connection point at electric power plant and apparatus |
| JP2020010546A (en) * | 2018-07-11 | 2020-01-16 | 愛知電機株式会社 | Self-excited reactive power compensator |
-
1992
- 1992-11-25 JP JP4338119A patent/JPH06161576A/en active Pending
Cited By (9)
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|---|---|---|---|---|
| WO2013151154A1 (en) * | 2012-04-06 | 2013-10-10 | 株式会社 東芝 | Short-circuit capacity observation method for power grid, and system thereof |
| JP2013219901A (en) * | 2012-04-06 | 2013-10-24 | Toshiba Corp | Short circuit capacity monitoring method of power system, and system of the same |
| CN104205546A (en) * | 2012-04-06 | 2014-12-10 | 株式会社东芝 | Short-circuit capacity observation method for power grid, and system thereof |
| CN104205546B (en) * | 2012-04-06 | 2017-04-19 | 株式会社东芝 | Short-circuit capacity observation method for power grid, and system thereof |
| US10175304B2 (en) | 2012-04-06 | 2019-01-08 | Kabushiki Kaisha Toshiba | Power-system short-circuit capacity monitoring method and system thereof |
| CN102790396A (en) * | 2012-08-28 | 2012-11-21 | 贵州电网公司电力调度控制中心 | Voltage stabilization open-loop control method on basis of short circuit capacity |
| JP2019176715A (en) * | 2018-03-29 | 2019-10-10 | サングロー パワー サプライ カンパニー リミテッド | Method for suppressing voltage fluctuation in common connection point at electric power plant and apparatus |
| JP2020010546A (en) * | 2018-07-11 | 2020-01-16 | 愛知電機株式会社 | Self-excited reactive power compensator |
| CN110163540A (en) * | 2019-06-28 | 2019-08-23 | 清华大学 | Electric power system transient stability prevention and control method and system |
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