JPH0471285B2

JPH0471285B2 -

Info

Publication number: JPH0471285B2
Application number: JP22590482A
Authority: JP
Inventors: Koji Suzuki; Shunji Tokuyama; Tokio Goto; Isao Takahashi; Kunio Hirasawa
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1982-12-24
Filing date: 1982-12-24
Publication date: 1992-11-13
Also published as: JPS59117027A

Description

【発明の詳細な説明】〔発明の利用分野〕本発明は、線路充電式直流しや断器に係り、特
に全体潮流反転制御時に好適な直流しや断器に関
する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a line-rechargeable direct current or disconnector, and particularly to a direct current or disconnector suitable for overall power flow reversal control.

[Prior art]

従来技術を第１図〜第４図をもとに説明する。 The prior art will be explained based on FIGS. 1 to 4.

第１図は、全体潮流反転制御方式（以下、潮流
反転制御）を示す回路図で第２図は動作例であ
る。通常直流系統は交流側よりトランス１を介し
て変換装置２で直流に変換（あるいはこの逆）し
線路を介して他の変換装置３で直流を交流に変換
（あるいはこの逆）しトランス４を介して電力の
供給を行なう。図は二端子送電例を示すが、多端
子送電も考慮して線路に直流しや断装置１０を設
けた例を示す。図の制御方式は電流マージンΔ
_ｄを切り換える方法によるもので直流電流設定値
_dpを両変換装置に加えた状態で、電流マージン
切換用スイツチ５をまたは側に切り換えて潮
流を反転することができる。両変換器にはそれぞ
れ定電流制御回路６，７および位相制御回路８，
９を設け、線路電流_d，_dp，Δ_dを比較して
いる動作例を第２図に示す。反転前（線路電圧が
正極性）は変換装置２側に動作特性で示す_dp
が加えられ、変換装置３側は、動作特性で示す
_dp−Δ_dとなりその交点Ａの動作点で運転さ
れている。もし全体潮流反転制御を行なう場合
は、電流マージン切換スイツチ５を側に切り換
えることで達成できる。第２図の反転後（線路電
圧が負極性）の動作特性から明らかなように、変
換装置２側に動作特性で示す_dp−Δ_d、変
換装置３側に動作特性で示す_dpが加えられ、
その交点Ｂの動作点で運転される。即ち、全体潮
流反転制御はこの電流マージン切換スイツチ５を
切り換える方法で行なわれる。 FIG. 1 is a circuit diagram showing an overall power flow reversal control system (hereinafter referred to as power flow reversal control), and FIG. 2 is an operation example. Normally, in a DC system, from the AC side, the converter 2 converts the DC into DC (or vice versa) via the transformer 1, and then converts the DC to AC (or vice versa) via the line with another converter 3, which then passes through the transformer 4. to supply electricity. Although the figure shows an example of two-terminal power transmission, it also shows an example in which a direct current or disconnection device 10 is provided on the line in consideration of multi-terminal power transmission. The control method in the figure is the current margin Δ
The DC current setting value is determined by the method of switching _d .
With _dp applied to both converters, the current margin changeover switch 5 can be switched to the or side to reverse the power flow. Both converters are provided with constant current control circuits 6 and 7 and phase control circuits 8 and 7, respectively.
FIG. 2 shows an example of operation in which line currents _d , _dp , and _Δd are compared. Before inversion (line voltage is positive polarity), _dp shown in the operating characteristics on the converter 2 side
is added, and the conversion device 3 side has the operating characteristics shown in
_dp - _Δd , and the motor is operated at the operating point of intersection A. If overall power flow reversal control is to be performed, it can be achieved by switching the current margin changeover switch 5 to the side. As is clear from the operating characteristics after inversion (line voltage is negative polarity) in Figure 2, _dp -Δ _d shown in the operating characteristics is added to the converter 2 side, _dp shown in the operating characteristics is added to the converter 3 side,
It is operated at the operating point of the intersection B. That is, the overall power flow reversal control is performed by switching the current margin changeover switch 5.

第３図は、第１図に示す直流しや断装置１０の
構成例を示したもので、線路電流の通電としや断
を行なう転流しや断器１１と、線路電圧を充電抵
抗ｒを通して充電するコンデンサＣ、および直流
をしや断するためのリアクトルＬ、投入スイツチ
１２、しや断後の過電圧抑制とエネルギ吸収のた
めの非線形抵抗（例えば酸化亜鉛抵抗）で構成さ
れている。第４図は潮流反転時の線路電流と線
路電圧ｖの波形例を示すもので、線路電流は一定
で、線路電圧の極性のみ時刻T₁〜T₂の間で反転
する。一般にこの時間は0.2〜0.5秒程度である。
もし、しや断器の高速再閉路などを考慮して充電
抵抗を小さい値に選ぶと、コンデンサの充電電圧
は第４図の電圧波形に等しくなり、潮流反転中に
地絡事故が発生し、線路電流をしや断する場合、
コンデンサの充電々圧が小さくしや断できないと
言う欠点があつた。また、充電抵抗を高く選ぶ
と、コンデンサＣの充放電時間が長くなる他、潮
流反転後、コンデンサの充電々圧の極性と線路電
圧の極性が異なると言う不具合を生ずる。また、
この場合に断路器の操作でコンデンサの極性を切
り換えることもできるが、制御方法との関連もあ
り、潮流反転中の事故時でも支障なくしや断でき
る方法が必要であつた。 FIG. 3 shows an example of the configuration of the direct current/disconnection device 10 shown in FIG. A reactor L for cutting off direct current, a closing switch 12, and a nonlinear resistor (for example, a zinc oxide resistor) for suppressing overvoltage and absorbing energy after cutting off the DC. FIG. 4 shows an example of the waveforms of the line current and line voltage v at the time of power flow reversal, where the line current is constant and only the polarity of the line voltage is reversed between times T ₁ and _{T 2} . Generally, this time is about 0.2 to 0.5 seconds.
If the charging resistance is chosen to be a small value, taking into consideration the high-speed reclosing of the circuit breaker, the charging voltage of the capacitor will be equal to the voltage waveform shown in Figure 4, and a ground fault will occur during power flow reversal. When cutting the line current,
The drawback was that the charging voltage of the capacitor was too small to be cut off. Furthermore, if the charging resistance is selected to be high, the charging/discharging time of the capacitor C becomes longer, and the polarity of the charging voltage of the capacitor differs from the polarity of the line voltage after the current flow is reversed. Also,
In this case, it is possible to switch the polarity of the capacitor by operating a disconnect switch, but this is related to the control method, and there was a need for a method that could disconnect the capacitor without any trouble even in the event of an accident during power flow reversal.

[Purpose of the invention]

本発明の目的は、線路電圧の極性が反転する間
でも支障なくしや断できる信頼性ある直流しや断
器を提供することにある。 SUMMARY OF THE INVENTION An object of the present invention is to provide a reliable direct current disconnector that can disconnect the line voltage without any trouble even when the polarity of the line voltage is reversed.

[Summary of the invention]

本発明は潮流反転制御は電流マージンの切り換
えによつて行なわれることに着目して、この電流
マージン切換スイツチとから直接あるいは間接的
に信号を得、この信号によつてコンデンサの極性
を反転する断路器を切換操作するようにしたこと
を特徴とする。 Focusing on the fact that power flow reversal control is performed by switching the current margin, the present invention provides a disconnection circuit that obtains a signal directly or indirectly from the current margin changeover switch, and uses this signal to reverse the polarity of the capacitor. The feature is that the device can be switched.

[Embodiments of the invention]

以下、本発明の一実施例を第５図により説明す
る。第３図と同一機能を有するものは同一番号で
示した。充電用コンデンサＣの両端に、コンデン
サ極性反転用のスイツチ１３，１４を設け、操作
器１５により接点ａ，a′または接点ｂ，b′に接続
される。接点ａとb′および接点ｂとa′は外部で接
続され、接点a′と大地間に充電抵抗ｒおよび接点
a′と転流しや断器の一端にリアクトルＬと投入ス
イツチ１２が直列に接続されＬ−Ｃの振動電流回
路を形成する。操作器１５は電流マージン切換ス
イツチ５からの信号を遅延装置１６で遅延させて
操作する。第６図に動作例を示す。今、電流マー
ジン切換スイツチ５を側に接続して一方の変換
器にΔ_dを加えている状態から電流マージン切
換スイツチ５を側に切換えて潮流反転制御をす
る場合、この切換信号を遅延装置１６でt₁だけ遅
延させた後スイツチ１５を動作させたもので、t₂
がスイツチ１３の操作時間である。充電抵抗ｒが
高抵抗であればコンデンサＣの端子電圧V_cは第
６図鎖線のごとくなり、しかも遅延時間t₁の選択
により、コンデンサの端子電圧は常に線路電圧の
極性と同極性で切離可能になりV_cの低下が防止
できる効果がある。 An embodiment of the present invention will be described below with reference to FIG. Components having the same functions as those in FIG. 3 are indicated by the same numbers. Switches 13 and 14 for reversing the polarity of the capacitor are provided at both ends of the charging capacitor C, and are connected to contacts a and a' or contacts b and b' by an operating device 15. Contacts a and b' and contacts b and a' are connected externally, and a charging resistor r and contact are connected between contact a' and ground.
A reactor L and a closing switch 12 are connected in series to one end of a' and a commutator or disconnector to form an LC oscillating current circuit. The operating device 15 is operated by delaying the signal from the current margin changeover switch 5 using a delay device 16. An example of operation is shown in FIG. If the current margin changeover switch 5 is connected to the side and Δ _d is applied to one converter, then when the current margin changeover switch 5 is changed to the side to perform power flow reversal control, this switching signal is transferred to the delay device 16. After delaying by t ₁ , switch 15 is operated, and t ₂
is the operation time of the switch 13. If the charging resistor r has a high resistance, the terminal voltage V _c of the capacitor C will be as shown by the chain line in Figure 6, and by selecting the delay time t ₁ , the terminal voltage of the capacitor will always be disconnected with the same polarity as the line voltage. This has the effect of preventing a drop in V _c .

第７図は他の実施例を示すもので、充電抵抗
r′を小さくして高速再閉路などの責務を考慮した
場合の構成を示す。コンデンサ切換用スイツチ１
７，１８に接点ａ，ｂ，ｃ，a′，b′，c′を設け、
接点ａ，a′から接点ｂ，b′に切換える操作器１９
と、接点ｂ，b′から接点ｃ，c′に切換える操作器
２１でコンデンサの極性を変更するもので、動作
例を第８図に示す。この場合は電流マージン切換
用スイツチ５を操作器１９からの信号により切換
えるもので、潮流反転制御を行なう場合、まず操
作器１９を操作して接点ａ，a′から接点ｂ，b′に
切り換える。 Figure 7 shows another embodiment, in which the charging resistor
The configuration is shown when r' is made small and responsibilities such as high-speed reclosing are considered. Capacitor switching switch 1
7, 18 are provided with contacts a, b, c, a', b', c',
Operator 19 for switching from contacts a, a' to contacts b, b'
The polarity of the capacitor is changed using an operating device 21 that switches from contacts b and b' to contacts c and c'. An example of operation is shown in FIG. In this case, the current margin changeover switch 5 is switched by a signal from the operating device 19. When carrying out power flow reversal control, the operating device 19 is first operated to switch from contacts a and a' to contacts b and b'.

この切換信号を操作器１９と連動する補助スイ
ツチから遅延装置２０を通してt₁だけ遅延させて
電流マージン切換スイツチ５を側から側に切
り換えて潮流反転制御を行なう。また潮流反転後
は、潮流反転前の信号より遅延装置２２を通して
t₂だけ遅延させた信号でスイツチの接点ｂ，b′か
ら接点ｃ，c′に切り換えて線路に接続される。こ
の構成によれば、潮流反転前にコンデンサを線路
から切り離し、潮流反転後、コンデンサの極性を
反転させて線路に接続させるため、コンデンサの
充電々圧の低位か防止できる効果がある第９図は他の実施例を示すための構成例であ
る。図はスイツチ１４と充電抵抗r′との間に接地
用断路部２３を設け、断路部用操作器２４，２５
でコンデンサＣと大地間の開閉操作を行なう。第
１０図は動作例を示す。潮流反転時はコンデンサ
切換用操作器１５と接地用断路器２３の操作器２
４を操作してコンデンサＣを線路から切り離した
後遅延装置２６で遅延した信号により電流マージ
ン切り換えスイツチ５を側から側へ切り換え
て潮流反転制御を行う。この場合は、潮流反転中
にスイツチ１３，１４は接点ａ，a′から接点ｂ，
b′に切り換わり、コンデンサＣの極性を反転す
る。しかし接地側断路部２３は開状態のため、コ
ンデンサＣの充電々圧の低下はなく潮流反転前の
線路電圧に保持される。潮流反転後は、潮流反転
時の電流マージン切換スイツチ５の切換信号より
遅延装置２７で遅延させた信号により接地側断路
器の操作器２５を動作させ断路部２３を投入し、
コンデンサＣの極性を反転した状態で負極性の線
路に接続され正常運転に戻る。本実施例によれ
ば、高速再閉路などの責務を満足させるよう充電
抵抗r′の値を小さくしても接地側断路器を開放し
て充電々圧の低下を防ぐと共に、潮流反転中にコ
ンデンサの極性切り換え操作ができるため潮流反
転中の事故時にも投入スイツチ１２を投入して転
流しや断器１１を開極してしや断できると言う効
果があり、信頼性ある直流しや断器が提供でき
る。 This switching signal is passed from an auxiliary switch linked to the operating device 19 to a delay device 20, and is delayed by _t1 to switch the current margin changeover switch 5 from one side to the other to perform power flow reversal control. In addition, after the power flow is reversed, the signal is passed through the delay device 22 from the signal before the power flow is reversed.
A signal delayed by t ₂ switches contacts b and b' of the switch to contacts c and c' and connects them to the line. According to this configuration, the capacitor is disconnected from the line before the current is reversed, and after the current is reversed, the polarity of the capacitor is reversed and connected to the line, which has the effect of preventing low charging voltage of the capacitor. This is a configuration example for showing another embodiment. In the figure, a grounding disconnection section 23 is provided between the switch 14 and the charging resistor r', and disconnection section operating devices 24, 25 are provided.
Open/close operation between capacitor C and ground is performed with . FIG. 10 shows an example of operation. When the power flow is reversed, the capacitor switching operation device 15 and the operation device 2 of the grounding disconnector 23
4 to disconnect the capacitor C from the line, the current margin changeover switch 5 is switched from one side to the other by a signal delayed by the delay device 26 to perform power flow reversal control. In this case, during the current reversal, switches 13 and 14 move from contacts a and a' to contacts b and
b' and reverses the polarity of capacitor C. However, since the ground side disconnector 23 is in an open state, the charging voltage of the capacitor C does not decrease and is maintained at the line voltage before the current reversal. After the power flow is reversed, the operating device 25 of the ground side disconnector is operated by a signal delayed by the delay device 27 from the switching signal of the current margin changeover switch 5 at the time of power flow reversal, and the disconnector 23 is closed.
With the polarity of capacitor C reversed, it is connected to the negative polarity line and normal operation is resumed. According to this embodiment, even if the value of the charging resistor r' is reduced to satisfy the requirements such as high-speed reclosing, the grounding side disconnector is opened to prevent a drop in the charging voltage, and the capacitor is Because the polarity can be switched, even in the event of an accident during power flow reversal, the switch 12 can be turned on to switch the current, or the disconnector 11 can be opened to disconnect the current. can be provided.

本発明の実施において、投入スイツチ１２に換
えてギヤツプ等の他の投入手段を用いても良く、
また線路電圧の極性反転信号として電流マージン
切換用スイツチを用いたが、変換器の定電圧制御
装置の出力値等を事故時と判別して用いる等他の
付随する信号を用いることができる。 In carrying out the present invention, other input means such as a gap may be used in place of the input switch 12.
Further, although a current margin changeover switch is used as a polarity reversal signal of the line voltage, other accompanying signals may be used, such as the output value of the constant voltage control device of the converter or the like, which is used to determine the occurrence of an accident.

〔Effect of the invention〕

以上のように本発明によれば、線路電圧の極性
が反転する間でも支承なくしや断できるので直流
しや断器の信頼性を向上できる。 As described above, according to the present invention, the support can be pierced or disconnected even when the polarity of the line voltage is reversed, so that the reliability of direct current and disconnection can be improved.

[Brief explanation of the drawing]

第１図は潮流反転制御例を説明する回路構成
図、第２図は第１図の動作例を示す特性図、第３
図は従来技術を説明する直流しや断器の回路構成
図、第４図は第３図の動作例を示す特性図、第５
図は本発明による一実施例を示す直流しや断器の
回路構成図、第６図は第５図の動作例を示す特性
図、第７図、第９図は本発明による他の実施例を
説明する直流しや断器の回路構成図、第８図、第
１０図は第７図、第９図の動作例を示す特性図で
ある。５……電流マージン切換用スイツチ、１１……
転流しや断器、１２……投入スイツチ、１３，１
４，１７，１８……コンデンサ極性切換スイツ
チ、１５，１９，２１……コンデンサ極性切換用
操作器、１６，２０，２２……遅延装置、ｒ……
充電抵抗、Ｌ……リアクトル、Ｃ……充電用コン
デンサ。 Fig. 1 is a circuit configuration diagram explaining an example of power flow reversal control, Fig. 2 is a characteristic diagram showing an operation example of Fig. 1, and Fig. 3
The figure is a circuit configuration diagram of a direct current and disconnector to explain the conventional technology, Figure 4 is a characteristic diagram showing an example of the operation of Figure 3, and Figure 5
The figure is a circuit diagram of a DC circuit and a circuit breaker showing one embodiment of the present invention, FIG. 6 is a characteristic diagram showing an example of the operation of FIG. 5, and FIGS. 7 and 9 are other embodiments of the present invention. FIGS. 8 and 10 are characteristic diagrams showing operation examples of FIGS. 7 and 9. 5...Current margin switching switch, 11...
Commutation and disconnection, 12... Closing switch, 13,1
4, 17, 18... Capacitor polarity switching switch, 15, 19, 21... Capacitor polarity switching operator, 16, 20, 22... Delay device, r...
Charging resistor, L...reactor, C...charging capacitor.

Claims

[Scope of Claims] 1. In a direct current or disconnection circuit in which a series circuit of a line charging capacitor connected to a line of a DC transmission system, a reactor, and a closing means is connected in parallel to a commutation or disconnection circuit, A direct current or disconnection device characterized by being provided with a polarity reversal connection device that connects the charging capacitor to the line with the polarity reversed when the polarity of the line voltage is reversed. 2. The device according to claim 1, wherein the polarity reversal connection device is a direct current or disconnector operated by a signal from a current margin switching switch. 3. In the device described in claim 1, the polarity reversal connection device has polarity switching switches on both sides of the charging capacitor, and the bipolar switching switch has polarity switching switches on both sides of the charging capacitor. A direct current or disconnector comprising a movable element connected to one end, and at least two stators connected to both end lines of the charging capacitor and capable of switching connection with the movable element.