JP7102776B2 - Static VAR compensator and its control circuit - Google Patents

Static VAR compensator and its control circuit Download PDF

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JP7102776B2
JP7102776B2 JP2018031454A JP2018031454A JP7102776B2 JP 7102776 B2 JP7102776 B2 JP 7102776B2 JP 2018031454 A JP2018031454 A JP 2018031454A JP 2018031454 A JP2018031454 A JP 2018031454A JP 7102776 B2 JP7102776 B2 JP 7102776B2
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博 篠原
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Description

本発明は、例えば、電力系統の三相または二相短絡事故によって発生する瞬時電圧低下を補償する無効電力補償装置及びその制御回路に関するものである。 The present invention relates to, for example, a static power compensator for compensating for an instantaneous voltage sag caused by a three-phase or two-phase short-circuit accident in a power system and a control circuit thereof.

図２は、無効電力補償装置の概略的な構成図である。
図２において、電力系統２０に連系される無効電力補償装置１０は、インバータ１１と変圧器１２と遮断器１３とを備えている。インバータ１１は、例えば図３に示すように、直流中間回路に設けられるコンデンサ１１ａと、還流ダイオードが接続されたＩＧＢＴやＧＴＯサイリスタ等の半導体スイッチング素子１１ｂ～１１ｇにより構成されている。 FIG. 2 is a schematic configuration diagram of the static VAR compensator.
In FIG. 2, the static VAR compensator 10 connected to the power system 20 includes an inverter 11, a transformer 12, and a circuit breaker 13. As shown in FIG. 3, for example, the inverter 11 is composed of a capacitor 11a provided in a DC intermediate circuit and semiconductor switching elements 11b to 11g such as an IGBT or GTO thyristor to which a freewheeling diode is connected.

上記の無効電力補償装置１０は、インバータ１１の出力電圧Ｖｉ及び出力電流Ｉｉを制御して電力系統２０に無効電力を注入し、電力系統２０のリアクタンス成分及び無効電流によって系統電圧Ｖｓの変動を補償している。 The above-mentioned ineffective power compensator 10 controls the output voltage Vi and the output current I i of the inverter 11 to inject the inactive power into the power system 20, and the system voltage V s is determined by the reactorance component and the ineffective current of the power system 20. Compensates for fluctuations.

図４は、無効電力補償装置１０の制御回路を示すブロック図である。
図４において、正相成分演算器３１は系統電圧Ｖｓの正相分（正相電圧）を検出し、電圧指令値と電圧検出値との偏差が減算器３２により演算される。電圧制御器３３は、上記偏差を零にするように動作して無効電流指令ＩＰｑ ＊を演算する。図２の無効電力補償装置１０は、この無効電流指令ＩＰｑ ＊に従ってインバータ１１の半導体スイッチング素子１１ｂ～１１ｇを制御し、電力系統２０に無効電力を注入することにより、系統電圧Ｖｓの変動を補償している。
この種の制御回路は、例えば特許文献１に記載されている。 FIG. 4 is a block diagram showing a control circuit of the static power compensator 10.
In FIG. 4, the positive phase component calculator 31 detects the positive phase component (positive phase voltage) of the system voltage Vs , and the deviation between the voltage command value and the voltage detected value is calculated by the subtractor 32. The voltage controller 33 operates so as to make the deviation zero, and calculates the reactive current command I Pq * . The reactive power compensator 10 of FIG. 2 controls the semiconductor switching elements 11b to 11g of the inverter 11 in accordance with the reactive current command I Pq * , and injects the reactive power into the power system 20 to cause fluctuations in the system voltage Vs. I am compensating.
This type of control circuit is described in, for example, Patent Document 1.

なお、特許文献１には明示されていないが、電圧制御器３３の出力側には、図４に示すようにリミッタ３４が設けられている。すなわち、無効電流指令ＩＰｑ ＊に従ってインバータ１１を構成する半導体スイッチング素子１１ｂ～１１ｇや還流ダイオードに定格値以上の電流が流れるとこれらが破損する恐れがあるので、リミッタ３４によって電流を定格値以下に制限しており、この技術は無効電力補償装置の制御回路として一般的である。 Although not specified in Patent Document 1, a limiter 34 is provided on the output side of the voltage controller 33 as shown in FIG. That is, if a current exceeding the rated value flows through the semiconductor switching elements 11b to 11g and the freewheeling diode constituting the inverter 11 in accordance with the invalid current command I Pq * , these may be damaged. Therefore, the limiter 34 reduces the current to the rated value or less. As a limitation, this technique is common as a control circuit for a diode-free power compensator.

さて、近年では、太陽光や風力等の再生可能エネルギーを利用した分散型電源が電力系統に導入されてきている。これらの分散型電源を備えた電力系統において、三相または二相短絡事故等により瞬時電圧低下が発生した時に分散型電源が一斉に解列されてしまうと、系統全体の電圧や周波数の維持に大きな影響を与える。
そこで、非特許文献１に記載されているように、低圧または高圧の電力系統に連系される分散型電源には事故時運転継続要件（ＦＲＴ要件）を満たすことが求められている。 By the way, in recent years, distributed power sources using renewable energy such as solar power and wind power have been introduced into electric power systems. In a power system equipped with these distributed power sources, if the distributed power sources are disconnected all at once when a momentary voltage sag occurs due to a three-phase or two-phase short-circuit accident, etc., the voltage and frequency of the entire system can be maintained. It has a big impact.
Therefore, as described in Non-Patent Document 1, the distributed power sources connected to the low-voltage or high-voltage power system are required to satisfy the accident operation continuation requirement (FRT requirement).

図５は、分散型電源と電力系統との間に設けられた連系変圧器のＹ結線側（高圧側）で三相短絡事故（図５（ａ））または二相短絡事故（図５（ｂ））が発生した場合の線間電圧の変化を示しており、非特許文献１に記載されているものである。なお、三相各相をＡ，Ｂ，Ｃ相とする。
前述したＦＲＴ要件においては、図５（ａ），（ｂ）に示すごとく、短絡事故によって残電圧が定格値の２０％～３０％に低下した場合でも、分散型電源の運転を一定時間、継続することが要求されている。 FIG. 5 shows a three-phase short-circuit accident (FIG. 5 (a)) or a two-phase short-circuit accident (FIG. 5 (Fig. 5)) on the Y connection side (high voltage side) of the interconnection transformer provided between the distributed power source and the power system. It shows the change of the line voltage when b)) occurs, and is described in Non-Patent Document 1. Each of the three phases is referred to as A, B, and C phases.
In the above-mentioned FRT requirements, as shown in FIGS. 5A and 5B, even if the residual voltage drops to 20% to 30% of the rated value due to a short circuit accident, the operation of the distributed power source is continued for a certain period of time. Is required to do.

特開平９－１５４２８４号公報（段落［００１３］～［００１９］、図１）Japanese Unexamined Patent Publication No. 9-154284 (paragraphs [0013] to [0019], FIG. 1)

「系統連系規程（ＪＥＡＣ９７０１－２０１６）」，ｐ.７４－８２，ｐ.１６９－１８０，一般社団法人日本電気協会 系統連系専門部会，２０１６年"System Connection Regulations (JEAC9701-2016)", p.74-82, p.169-180, Japan Electric Association System Connection Expert Subcommittee, 2016

図４に示した従来技術によれば、無効電力補償装置１０の動作によって電力系統２０の電圧変動を補償することが可能であり、その電圧補償効果は、無効電力補償装置１０から出力される無効電流と電力系統２０のリアクタンス成分とによって決定される。ここで、電力系統２０のリアクタンス成分を無効電力補償装置１０により制御することは不可能であるため、無効電流の大きさが系統電圧の補償効果を決定することになる。 According to the prior art shown in FIG. 4, it is possible to compensate the voltage fluctuation of the power system 20 by the operation of the ineffective power compensating device 10, and the voltage compensation effect is the invalidity output from the ineffective power compensating device 10. It is determined by the current and the reactance component of the power system 20. Here, since it is impossible to control the reactance component of the power system 20 by the static power compensator 10, the magnitude of the reactive current determines the compensation effect of the system voltage.

特に、前述したＦＲＴ要件により規定された三相または二相短絡時の瞬時電圧低下を補償する場合には、瞬間的に大きく低下する系統電圧を補償するための無効電流を出力する必要があり、無効電力補償装置１０から出力される無効電流はできるだけ大きくすることが望まれる。
この無効電流が小さく補償電圧が小さい場合には、系統電圧が低い状態が続いて分散型電源が解列してしまい、系統全体の電圧や周波数の維持に大きな影響を与えてしまう。
電力系統２０に対する電圧補償能力を高めるには無効電力補償装置１０の容量を大きくすれば良いが、装置容量を通常運転時に必要とされる以上の大きさにすることはコストの増加を招くという問題がある。 In particular, when compensating for the instantaneous voltage drop at the time of a three-phase or two-phase short circuit specified by the FRT requirement described above, it is necessary to output a reactive current for compensating for the system voltage that drops significantly momentarily. It is desirable that the reactive current output from the reactive power compensator 10 be as large as possible.
If the reactive current is small and the compensation voltage is small, the system voltage remains low and the distributed power sources are disconnected, which greatly affects the maintenance of the voltage and frequency of the entire system.
In order to increase the voltage compensation capacity for the power system 20, the capacity of the static VAR compensator 10 may be increased, but increasing the capacity of the device to a size larger than that required during normal operation causes an increase in cost. There is.

そこで、本発明の解決課題は、装置容量を増大させることなく、系統電圧の瞬時低下時の電圧補償を確実に行い、分散型電源の解列を防止するようにした無効電力補償装置及びその制御回路を提供することにある。 Therefore, the problem to be solved by the present invention is a static power compensator and its control that ensure voltage compensation when the system voltage drops instantaneously and prevent disconnection of the distributed power source without increasing the device capacity. To provide the circuit.

上記課題を解決するため、請求項１に係る無効電力補償装置は、インバータにより電力系統に無効電力を出力して系統電圧の変動を補償する無効電力補償装置において、
前記系統電圧が閾値以下に低下した時に、前記系統電圧の低下を解消するために前記無効電力補償装置の定格電流値を超える第１の無効電流を第１の時間にわたり前記インバータから出力させ、前記第１の時間の経過後に、この第１の時間に応じて予め設定された時間であって前記インバータを構成する半導体素子を冷却するための第２の時間に従って第２の無効電流を前記インバータから出力させるように無効電流指令を生成することを特徴とする。 In order to solve the above problem, the static power compensator according to claim 1 is a static power compensator that outputs invalid power to the power system by an inverter to compensate for fluctuations in the system voltage.
When the system voltage drops below the threshold value, a first reactive current exceeding the rated current value of the reactive power compensator is output from the inverter for a first time in order to eliminate the drop in the system voltage. After the lapse of the first time, a second reactive current is generated from the inverter according to a second time for cooling the semiconductor element constituting the inverter, which is a preset time according to the first time. It is characterized by generating a reactive current command so as to output it .

請求項２に係る無効電力補償装置の制御回路は、インバータにより電力系統に無効電力を出力して系統電圧の変動を補償する無効電力補償装置の制御回路において、
前記系統電圧が閾値以下に低下したことを判定する判定手段と、
前記無効電力補償装置の定格電流値を超える第１の無効電流指令と前記定格電流値以下の第２の無効電流指令とを切替可能とした切替手段と、
前記判定手段による判定信号に従って前記第１の無効電流指令を第１の時間にわたって選択し、かつ、前記第１の時間の経過後に、前記第１の時間に応じて予め設定された時間であって前記インバータを構成する半導体素子の冷却時間を考慮した第２の時間が経過するまでは前記第２の無効電流指令を選択するように前記切替手段を制御する手段と、
前記第１の無効電流指令または前記第２の無効電流指令に従って前記インバータを制御する手段と、
を備えたことを特徴とする。 The control circuit of the reactive power compensator according to claim 2 is the control circuit of the reactive power compensator that outputs the reactive power to the power system by the inverter to compensate for the fluctuation of the system voltage .
A determination means for determining that the system voltage has dropped below the threshold value, and
A switching means capable of switching between a first reactive current command that exceeds the rated current value of the reactive power compensator and a second reactive current command that is equal to or lower than the rated current value.
The first invalid current command is selected over the first time according to the determination signal by the determination means, and after the lapse of the first time, the time is set in advance according to the first time. A means for controlling the switching means so as to select the second invalid current command until a second time in consideration of the cooling time of the semiconductor element constituting the inverter elapses.
A means for controlling the inverter according to the first reactive current command or the second reactive current command, and
It is characterized by being equipped with .

本発明によれば、三相短絡や二相短絡事故等によって系統電圧が瞬時に低下した場合でも、装置の定格電流値を超える無効電流を短時間出力して系統電圧を増加させ、系統電圧の低下を補償することができる。これにより、分散型電源の解列を未然に防止して系統全体の電圧や周波数に悪影響を及ぼすことがない。
また、無効電力補償装置の容量を必要以上に大きくする必要がないため、コストの低減にも寄与する。 According to the present invention, even when the system voltage drops instantaneously due to a three-phase short circuit or a two-phase short circuit accident, an invalid current exceeding the rated current value of the device is output for a short time to increase the system voltage and increase the system voltage. The decline can be compensated. As a result, disconnection of the distributed power source is prevented and the voltage and frequency of the entire system are not adversely affected.
In addition, since it is not necessary to increase the capacity of the static power compensator more than necessary, it also contributes to cost reduction.

本発明の実施形態に係る無効電力補償装置の制御回路のブロック図である。It is a block diagram of the control circuit of the static power compensator which concerns on embodiment of this invention. 無効電力補償装置の概略的な構成図である。It is a schematic block diagram of the static power compensator. 図２におけるインバータの主回路構成図である。It is a main circuit block diagram of the inverter in FIG. 無効電力補償装置の従来の制御回路を示すブロック図である。It is a block diagram which shows the conventional control circuit of a static power compensator. 非特許文献１に記載された、電力系統の短絡事故による線間電圧の変化を示す図である。It is a figure which shows the change of the line voltage by the short circuit accident of the electric power system described in Non-Patent Document 1.

以下、図に沿って本発明の実施形態を説明する。
図１は、この実施形態に係る無効電力補償装置の制御回路のブロック図である。図１において、図４と同一の部分については同一の符号を付して説明を省略し、以下では図４との相違点を中心に説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram of a control circuit of the static power compensator according to this embodiment. In FIG. 1, the same parts as those in FIG. 4 are designated by the same reference numerals and description thereof will be omitted, and the differences from FIG. 4 will be mainly described below.

図１に示す実施形態では、正相電圧演算器３１から出力される系統電圧検出値が電圧低下判定器３７に入力されている。電圧低下判定器３７は、系統電圧検出値が閾値未満になると一定時間（ΔＴ１とする）にわたり、または、この時間内で系統電圧の低下が解消されるまで、「Ｈｉｇｈ」レベルの電圧低下判定信号ＳＴＡを出力する。
電圧低下判定信号ＳＴＡはタイマ３８に入力されており、タイマ３８は、電圧低下判定信号ＳＴＡが「Ｌｏｗ」レベルになると、「Ｈｉｇｈ」レベルの強制停止信号ＳＴＰを一定時間（ΔＴ２とする）だけ出力する。 In the embodiment shown in FIG. 1, the system voltage detection value output from the positive phase voltage calculator 31 is input to the voltage drop determination device 37. The voltage drop determination device 37 determines the voltage drop at the “High” level for a certain period of time (ΔT 1 ) when the system voltage detection value becomes less than the threshold value, or until the system voltage drop is resolved within this time. Output the signal STA.
The voltage drop determination signal STA is input to the timer 38, and when the voltage drop determination signal STA reaches the “Low” level, the timer 38 sets the “High” level forced stop signal STP for a certain period of time (ΔT 2 ). Output.

また、リミッタ３４の出力側にはスイッチ（切替手段）３５が設けられている。このスイッチ３５の一方の入力端子Ａにはリミッタ３４の出力信号（第２の無効電流指令）が加えられ、他方の入力端子Ｂには、設定器３６により設定された無効電流指令（第１の無効電流指令）が加えられている。設定器３６には、リミッタ３４による定格値（±１００％）を超える大きさの第１の無効電流指令が設定されているが、その設定値と、電圧低下判定信号ＳＴＡが「Ｈｉｇｈ」レベルを維持する時間ΔＴ１とは、インバータ１１を構成する半導体スイッチング素子１１ｂ～１１ｇや還流ダイオード等の素子が過熱によって破損しない許容範囲内で決定される。 Further, a switch (switching means) 35 is provided on the output side of the limiter 34. The output signal of the limiter 34 (second reactive current command) is applied to one input terminal A of the switch 35, and the reactive current command (first reactive current command) set by the setter 36 is applied to the other input terminal B. Reactive current command) has been added. A first reactive current command having a magnitude exceeding the rated value (± 100%) by the limiter 34 is set in the setter 36, and the set value and the voltage drop determination signal STA set the “High” level. The maintenance time ΔT 1 is determined within an allowable range in which elements such as semiconductor switching elements 11b to 11g and a freewheeling diode constituting the inverter 11 are not damaged by overheating.

スイッチ３５は、前述した電圧低下判定信号ＳＴＡが「Ｈｉｇｈ」レベルの時に入力端子Ｂを、判定信号ＳＴＡが「Ｌｏｗ」レベルの時に入力端子Ａを選択するように切替可能であり、これらの入力端子Ａ，Ｂの何れかの入力信号を無効電流指令ＩＰｑ ＊として出力する。
図２の無効電力補償装置１０は、この無効電流指令ＩＰｑ ＊に従ってインバータ１１の半導体スイッチング素子１１ｂ～１１ｇを制御して電力系統２０に無効電力を注入し、系統電圧Ｖｓの変動を補償する。 The switch 35 can be switched so as to select the input terminal B when the voltage drop determination signal STA described above is at the “High” level and the input terminal A when the determination signal STA is at the “Low” level. The input signal of either A or B is output as an invalid current command IPq * .
The reactive power compensator 10 of FIG. 2 controls the semiconductor switching elements 11b to 11g of the inverter 11 in accordance with the reactive current command I Pq * to inject the reactive power into the power system 20 and compensate for the fluctuation of the system voltage Vs. ..

なお、無効電流指令は無効電力指令と同義であるため、図１の実施形態において、無効電流指令の代わりに、無効電力指令を用いても良いことは言うまでもない。 Since the reactive current command is synonymous with the reactive power command, it goes without saying that the reactive power command may be used instead of the reactive current command in the embodiment of FIG.

次に、この実施形態の動作を詳述する。
系統電圧検出値が閾値を超えている通常時には、電圧低下判定信号ＳＴＡが「Ｌｏｗ」レベルであり、スイッチ３５は入力端子Ａ側に接続されている。このため、リミッタ３４により定格電流値である１００％以下に制限された第２の無効電流指令ＩＰｑ ＊が、スイッチ３５を介して出力され、定格値以下の無効電力が電力系統２０に注入されて電圧補償が行われる。 Next, the operation of this embodiment will be described in detail.
Normally, when the system voltage detection value exceeds the threshold value, the voltage drop determination signal STA is at the “Low” level, and the switch 35 is connected to the input terminal A side. Therefore, the second reactive current command IPq * limited to 100% or less of the rated current value by the limiter 34 is output via the switch 35, and the reactive power of the rated current value or less is injected into the power system 20. Voltage compensation is performed.

また、電力系統２０に三相または二相短絡事故等が発生して系統電圧Ｖｓが瞬時に低下し、系統電圧検出値が閾値以下になった状態が所定時間継続すると、電圧低下判定器３７による電圧低下判定信号ＳＴＡが一定時間ΔＴ１にわたって「Ｈｉｇｈ」レベルになる。この電圧低下判定信号ＳＴＡによりスイッチ３５は入力端子Ｂ側に切り替わり、設定器３６による予め設定されている設定値、すなわち、装置の定格電流値を超える第１の無効電流指令ＩＰｑ ＊がスイッチ３５を介して出力される。
このため、上記の一定時間ΔＴ１では、第１の無効電流指令ＩＰｑ ＊に従ってインバータ１１の半導体スイッチング素子１１ｂ～１１ｇが動作することにより、定格値を超える無効電力が電力系統２０に注入されて系統電圧Ｖｓの低下を補償する。 Further, when a three-phase or two-phase short-circuit accident or the like occurs in the power system 20 and the system voltage Vs drops instantaneously and the system voltage detection value becomes equal to or lower than the threshold value for a predetermined time, the voltage drop judgment device 37 The voltage drop determination signal STA due to the above becomes the “High” level over a certain period of time ΔT 1 . By this voltage drop determination signal STA, the switch 35 is switched to the input terminal B side, and the first reactive current command I Pq * that exceeds the preset value set by the setter 36, that is, the rated current value of the device is set to the switch 35. Is output via.
Therefore, in the above-mentioned constant time ΔT 1 , the semiconductor switching elements 11b to 11g of the inverter 11 operate in accordance with the first invalid current command I Pq * , so that the reactive power exceeding the rated value is injected into the power system 20. Compensates for the drop in system voltage V s .

系統電圧Ｖｓが上昇して電圧低下判定信号ＳＴＡが「Ｌｏｗ」レベルになると、スイッチ３５が入力端子Ａ側に切り替わると共に、タイマ３８は、一定時間（ΔＴ２とする）にわたって「Ｈｉｇｈ」レベルの強制停止信号ＳＴＰを電圧低下判定器３７に出力する。電圧低下判定器３７では、強制停止信号ＳＴＰが「Ｈｉｇｈ」レベルである時間ΔＴ２は電圧低下判定信号ＳＴＡを「Ｌｏｗ」レベルに保つことにより、リミッタ３４を介した第２の無効電流指令ＩＰｑ ＊を出力する状態が維持される。強制停止信号ＳＴＰが「Ｈｉｇｈ」レベルである時間ΔＴ２中は、インバータを構成する半導体素子を破損させないため、系統電圧Ｖｓが所定の閾値以下になっても電圧低下判定信号ＳＴＡは「Ｌｏｗ」レベルを維持し「Ｈｉｇｈ」レベルになることはない。系統電圧Ｖｓの低下が解消されず継続している場合は、ΔＴ２経過後に電圧低下判定信号ＳＴＡは「Ｈｉｇｈ」レベルとなり、再度定格値を超える無効電力が電力系統２０に注入されて系統電圧Ｖｓの低下を補償する。 When the system voltage V s rises and the voltage drop determination signal STA reaches the "Low" level, the switch 35 switches to the input terminal A side, and the timer 38 is set to the "High" level for a certain period of time (assumed to be ΔT 2 ). The forced stop signal STP is output to the voltage drop determination device 37. In the voltage drop determination device 37, the time ΔT 2 at which the forced stop signal STP is at the “High” level keeps the voltage drop determination signal STA at the “Low” level, so that the second reactive current command I Pq via the limiter 34 The state of outputting * is maintained. During the time ΔT 2 when the forced stop signal STP is at the “High” level, the semiconductor element constituting the inverter is not damaged. Therefore, even if the system voltage V s falls below a predetermined threshold, the voltage drop determination signal STA is “Low”. It maintains the level and never reaches the "High" level. If the decrease in the system voltage V s is not resolved and continues, the voltage decrease determination signal STA becomes the “High” level after ΔT 2 elapses, and the ineffective power exceeding the rated value is injected into the power system 20 again to the system voltage. Compensate for the decrease in Vs.

なお、無効電力補償装置１０が定格値以上の無効電力を出力していても、許容時間内に系統電圧Ｖｓの低下が解消した場合には、系統電圧Ｖｓが復帰するまでの時間に応じてインバータ１１の半導体スイッチング素子１１ｂ～１１ｇや還流ダイオード等の半導体素子を冷却すれば良い。 Even if the ineffective power compensator 10 outputs an ineffective power equal to or higher than the rated value, if the decrease in the system voltage V s is resolved within the permissible time, the system voltage V s depends on the time until the system voltage V s is restored. The semiconductor switching elements 11b to 11g of the inverter 11 and the semiconductor elements such as the freewheeling diode may be cooled.

すなわち、電圧低下判定信号ＳＴＡが「Ｈｉｇｈ」レベルである時間ΔＴ１（定格電流値を超える無効電流を出力している時間）と、その後に電圧低下判定信号ＳＴＡが「Ｌｏｗ」レベルに移行してから信号ＳＴＰを「Ｈｉｇｈ」レベルにして信号ＳＴＡを「Ｌｏｗ」レベルのまま維持する時間ΔＴ２（無効電流を定格電流値以下に抑制して半導体素子の冷却を促す時間）との間には一定の関係があることから、信号ＳＴＡが「Ｈｉｇｈ」レベルである時間ΔＴ１に応じた信号ＳＴＰの「Ｈｉｇｈ」レベルの時間ΔＴ２をテーブルデータとして予め用意しておき、このテーブルデータに基づいて上記の時間ΔＴ２を決定しても良い。 That is, the time ΔT 1 (the time during which the invalid current exceeding the rated current value is output) when the voltage drop judgment signal STA is at the “High” level, and then the voltage drop judgment signal STA shifts to the “Low” level. The time to keep the signal STP at the “High” level and the signal STA at the “Low” level ΔT 2 (the time to suppress the invalid current below the rated current value and promote the cooling of the semiconductor element) is constant. Therefore, the time ΔT 2 at the “High” level of the signal STP corresponding to the time ΔT 1 at which the signal STA is at the “High” level is prepared in advance as table data, and the above is based on this table data. The time ΔT 2 of may be determined.

以上のような動作により、無効電力補償装置１０から出力される無効電流及び電圧補償量を、許容し得る短時間だけ大きくすることにより、電力系統２０の短絡事故発生時における分散型電源の解列を抑制して系統全体の電圧や周波数の維持に悪影響が及ぶのを防止することができる。 By the above operation, the reactive current and the voltage compensation amount output from the reactive power compensating device 10 are increased by an acceptable short time, so that the distributed power source is disconnected when a short-circuit accident occurs in the power system 20. It is possible to prevent the maintenance of the voltage and frequency of the entire system from being adversely affected.

なお、本発明の他の形態として信号ＳＴＡが「Ｈｉｇｈ」レベルである時間ΔＴ１においてリミッタ３４の制限値を１００％以下から１００％超に切り替えるようにしても良い。 As another embodiment of the present invention, the limit value of the limiter 34 may be switched from 100% or less to more than 100% at the time ΔT 1 when the signal STA is at the “High” level.

１０：無効電力補償装置
１１：インバータ
１１ａ：コンデンサ。
１１ｂ～１１ｇ：半導体スイッチング素子
１２：変圧器
１３：遮断器
２０：電力系統
３１：正相電圧演算器
３２：減算器
３３：電圧制御器
３４：リミッタ
３５：スイッチ
３６：設定器
３７：電圧低下判定器
３８：タイマ 10: Static power compensator 11: Inverter 11a: Capacitor.
11b to 11g: Semiconductor switching element 12: Transformer 13: Circuit breaker 20: Power system 31: Positive phase voltage calculator 32: Subtractor 33: Voltage controller 34: Limiter 35: Switch 36: Setting device 37: Voltage drop judgment Vessel 38: Timer

Claims (2)

インバータにより電力系統に無効電力を出力して系統電圧の変動を補償する無効電力補償装置において、
前記系統電圧が閾値以下に低下した時に、前記系統電圧の低下を解消するために前記無効電力補償装置の定格電流値を超える第１の無効電流を第１の時間にわたり前記インバータから出力させ、前記第１の時間の経過後に、この第１の時間に応じて予め設定された時間であって前記インバータを構成する半導体素子を冷却するための第２の時間に従って第２の無効電流を前記インバータから出力させるように無効電流指令を生成することを特徴とする無効電力補償装置。 In an indemnity power compensator that outputs indemnity power to the power system by an inverter to compensate for fluctuations in system voltage.
When the system voltage drops below the threshold value, a first reactive current exceeding the rated current value of the reactive power compensator is output from the inverter for a first time in order to eliminate the drop in the system voltage. After the lapse of the first time, a second reactive current is generated from the inverter according to a second time for cooling the semiconductor element constituting the inverter, which is a preset time according to the first time. A reactive power compensator characterized in generating a reactive current command to output . インバータにより電力系統に無効電力を出力して系統電圧の変動を補償する無効電力補償装置の制御回路において、
前記系統電圧が閾値以下に低下したことを判定する判定手段と、
前記無効電力補償装置の定格電流値を超える第１の無効電流指令と前記定格電流値以下の第２の無効電流指令とを切替可能とした切替手段と、
前記判定手段による判定信号に従って前記第１の無効電流指令を第１の時間にわたって選択し、かつ、前記第１の時間の経過後に、前記第１の時間に応じて予め設定された時間であって前記インバータを構成する半導体素子の冷却時間を考慮した第２の時間が経過するまでは前記第２の無効電流指令を選択するように前記切替手段を制御する手段と、
前記第１の無効電流指令または前記第２の無効電流指令に従って前記インバータを制御する手段と、
を備えたことを特徴とする無効電力補償装置の制御回路。 In the control circuit of the static power compensator that outputs the static power to the power system by the inverter and compensates for the fluctuation of the system voltage .
A determination means for determining that the system voltage has dropped below the threshold value, and
A switching means capable of switching between a first reactive current command that exceeds the rated current value of the reactive power compensator and a second reactive current command that is equal to or lower than the rated current value.
The first invalid current command is selected over the first time according to the determination signal by the determination means, and after the lapse of the first time, the time is set in advance according to the first time. A means for controlling the switching means so as to select the second invalid current command until a second time in consideration of the cooling time of the semiconductor element constituting the inverter elapses.
A means for controlling the inverter according to the first reactive current command or the second reactive current command, and
A control circuit for a static VAR compensator.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005318755A (en) 2004-04-30 2005-11-10 Kansai Electric Power Co Inc:The Inverter control system
JP2008305041A (en) 2007-06-06 2008-12-18 Chugoku Electric Power Co Inc:The Over-loading prevention device for static reactive power compensation device
US20140112038A1 (en) 2011-06-29 2014-04-24 Jean-Philippe Hasler Method And Controller For Protecting A Voltage Source Converter
JP2019149849A (en) 2018-02-26 2019-09-05 富士電機株式会社 Reactive power compensator and control circuit therefor

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6266308A (en) * 1985-09-18 1987-03-25 Toshiba Corp Control method for stationary type reactive power compensating device
JPH09154284A (en) * 1995-11-27 1997-06-10 Tokyo Electric Power Co Inc:The Power converter controller

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005318755A (en) 2004-04-30 2005-11-10 Kansai Electric Power Co Inc:The Inverter control system
JP2008305041A (en) 2007-06-06 2008-12-18 Chugoku Electric Power Co Inc:The Over-loading prevention device for static reactive power compensation device
US20140112038A1 (en) 2011-06-29 2014-04-24 Jean-Philippe Hasler Method And Controller For Protecting A Voltage Source Converter
JP2019149849A (en) 2018-02-26 2019-09-05 富士電機株式会社 Reactive power compensator and control circuit therefor

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
系統連系規程 （電機技術規程系統連系編） ＪＥＡＣ９７０１－２０１６，第７版，日本，日本電気協会発行，2016年08月09日，P169-P180

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