JP2004153941A - Controller for ac excitation type generator motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for a generator motor which can enhance the excessive stability of a power system without stopping an AC excitation type generator motor (hereinafter referred to as a generator motor). <P>SOLUTION: In the power system, there is such a case that the excessive stability drops by the unbalance of power demand and the supply of the power system at the occurrence of a large disturbance such as a one-line earth fault or three-phase short circuit. To prevent it, when, for example, surplus power is generated and the system is accelerated and the frequency of the generator motor 1 gets over the specified frequency after the detection of a system accident by a system accident detector 32, an acceleration/deceleration control signal generator 33 computes available, that is, absorbable rotational energy from the number of revolutions and the allowable revolution range of the generator motor at that time, and controls the active power of the generator motor via a q-axis controller 15 and a converter controller 6, according to this absorbable rotational energy thereby absorbing the surplus energy as the rotational energy of the generator motor so as to enhance the excessive stability of the power system. <P>COPYRIGHT: (C)2004,JPO

Description

にて求められる。従って、運転可能回転数の上限値をＮｍａｘとすると、回転数がＮからＮｍａｘまで変化する時の回転エネルギーΔＥは、式（２）にて求まる。

【００２６】
回転エネルギーΔＥはＷ・秒の単位であり、シミュレーション計算などにより決定した加速抑制の制御継続時間をｔとすると、このときの有効電力の可能制御量ΔＰｃは、
ΔＰｃ＝ΔＥ／ｔ （３）
で求まる。有効電力値計算手段３３ｆは、制御継続時間設定手段３３ｅに予め設定された上記制御継続時間ｔと、上記ΔＥとから、上記（３）式に基づきΔＰｃを計算する。
これに基づき、抑制信号生成手段３３ｇにて生成される抑制信号Ｓ６を、このΔＰｃ、ｔの関数による図２の抑制信号生成手段３３ｇの枠内に示すような、一定時間ｔの間有効電力をΔＰだけ減少させる信号とすることにより、交流励磁形発電電動機１を過度に制御することなく運転許容限度内での電力系統の加減速抑制制御を実現できる。
【００２７】
具体的には、図１に示すように抑制信号Ｓ６を電力偏差検出器１４に加算することにより、有効電力を低下させる方向に制御し電力系統の加速を抑制する。つまり、電力系統が加速されるのは発電量＞負荷（需要）量の状態であるので、発生有効電力を少なくし、交流励磁形発電電動機１の回転エネルギーとして吸収させることにより、電力系統の加速を抑制することができる。
【００２８】
電力系統３に事故が発生した場合、事故発生信号Ｓ１が系統事故検出器３２から出され、事故時抑制指令信号発信手段３３ａは交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆαを超えると、事故時抑制指令信号Ｓ２を発する。事故時抑制指令信号Ｓ２を受けた後、利用可能回転エネルギー計算手段３３ｃ、有効電力値計算手段３３ｆ、抑制信号生成手段３３ｇは上述のように動作し、抑制信号Ｓ６を発信する。
【００２９】
なお、電力系統が減速した場合の制御も、固定子巻線電圧の周波数ｆｇが所定の周波数ｆβを下回ったことを検出すること、交流励磁形発電電動機１の回転数がＮｍｉｎを下回らないようにしながら、最速にて交流励磁形発電電動機１の回転エネルギーを放出させ有効電力Ｐｇを増加させる方向に制御する以外は上述した電力系統が加速した場合の制御と同様である。
また、上記はｑ軸制御として有効電力を制御している例を示したが、ｑ軸制御として回転数あるいはすべりを制御している場合でも、同様の効果を得ることができる。
【００３０】
なお、応答時間を短縮するために、利用可能回転エネルギー計算手段３３ｃや有効電力値計算手段３３ｆの代わりに、例えば利用可能な回転エネルギーを求める手段としての有効電力値記憶手段を設け、この有効電力値記憶手段に回転数に対応させて予め算出しておいた利用可能回転エネルギーΔＥ及び可能制御量ΔＰｃをテーブルとして記憶させておき、事故発生信号Ｓ１が発信されたとき、当該テーブルを参照して回転数Ｎに対応した可能制御量ΔＰｃを読み出すようにすることもできる。
【００３１】
以上のように、この実施の形態によれば、利用可能な回転エネルギーを求め、電力系統の事故が検出されたとき、利用可能な回転エネルギーと予め定められた抑制継続時間とから求めた交流励磁形発電電動機の有効電力の可能制御量だけ交流励磁形発電電動機の有効電力を増減して、すなわち利用可能な回転エネルギーに応じて交流励磁形発電電動機の有効電力を増減することにより、利用可能な回転エネルギーを最大限に活用して交流励磁形発電電動機を停止することなく電力系統の動揺を迅速に抑制し、電力系統の過渡安定度を向上させることができる。
【００３２】
また、交流励磁形発電電動機１の固定子巻線電圧Ｖｇ、周波数ｆｇ、電流Ｊｇ、電力Ｐｇなどの交流励磁形発電電動機の諸量の情報だけに基づいて、交流励磁形発電電動機１の有効電力を制御することができる。従って、交流励磁形発電電動機の制御装置と電力系統との距離が遠い場合でも、信号の伝送遅れ、信号品質の低下、建設費の増加などを防止できる。
【００３３】
実施の形態２．
図５及び図６はこの発明の他の実施の形態を示すものであり、図５は交流励磁形発電電動機の制御装置の構成図、図６は図５の加減速抑制信号発生器の構成図である。この実施の形態においては、図５のように加減速抑制信号発生器１３３を設けている。加減速抑制信号発生器１３３は、図６に示すように制御継続時間計算手段１３３ｅ、制御可能有効電力値計算手段１３３ｆ及び動揺抑制手段としての抑制信号生成手段１３３ｇを有する。その他の構成については、図１及び図２に示した実施の形態１と同様のものであるので、相当するものに同じ符号を付して説明を省略する。
【００３４】
交流励磁形発電電動機１は、固定子の電流容量、回転子の電流容量あるいは制御装置、電力変換器の性能から運転可能な有効電力の範囲が決まっている。この運転可能な有効電力の最大値をＰｍａｘ、最小値をＰｍｉｎ、そのときの運転有効電力をＰａとすると、利用可能な有効電力値は、（Ｐｍａｘ−Ｐａ）、あるいは（Ｐｍｉｎ−Ｐａ）となる。制御可能有効電力値計算手段１３３ｆが、この（Ｐｍａｘ−Ｐａ）、あるいは（Ｐｍｉｎ−Ｐａ）を求める。これをΔＰｍａとする。
【００３５】
次に、制御継続時間計算手段１３３ｅが、このΔＰｍａと上記（２）式に示した利用可能な回転エネルギーΔＥとから制御継続時間ｔ１を次のようにして求める。
ｔ１＝ΔＥ／ΔＰｍａ （４）
抑制信号生成手段１３３ｇは、抑制信号Ｓ７をこのΔＰｍａ、ｔ１の関数による図６の抑制信号生成手段１３３ｇの枠内に示すような、一定時間ｔ１の間有効電力をΔＰｍａだけ減少させる信号とすることにより、交流励磁形発電電動機１を過度に制御することなく許容運転限度内での加減速抑制制御を行い、事故時の電力系統の過渡安定度を確保する。
【００３６】
なお、利用可能な有効電力は、必要に応じ、定常的な運転に対する定格値、時間の関数で表される過渡的な限界値のどちらを適用してもよい。
また、図示していないが、電力系統の加減速抑制制御により電力系統が減速状態となった後も加速抑制制御を継続すると電力系統の減速を拡大し電力系統を不安定にする可能性があるため、上述の加減速抑制信号発生器１３３には、上記計算により求まった制御時間ｔ１に関係なく、一定時間で、あるいは周波数変化など例えば周波数が低下方向に転じたことを検出し、この抑制制御Ｓ７を止める加減速抑制制御停止器が付加されている。
【００３７】
以上のように、この実施の形態によれば、利用可能な回転エネルギーと制御可能有効電力値とから制御継続時間を求め、電力系統の事故が検出されたとき、制御可能有効電力値だけ交流励磁形発電電動機の有効電力を増減して、すなわち利用可能な回転エネルギーに応じて交流励磁形発電電動機の有効電力を増減することにより、利用可能な回転エネルギーを最大限に活用して交流励磁形発電電動機を停止することなく電力系統の動揺を迅速に抑制し、電力系統の過渡安定度を向上させることができる。
【００３８】
実施の形態３．
図７、図８はさらにこの発明の他の実施の形態を示すものであり、図７は交流励磁形発電電動機の制御装置の構成図、図８は図７の条件検出器のロジック回路図である。以上に示した実施の形態１及び２は、加減速抑制のための信号を制御目標有効電力設定器１３の設定値に加算する方式であるが、加減速抑制制御を行うときは図７に示すように制御モード切換器３５によりｑ軸制御を回転数制御に切り換え、その制御目標回転数を運転可能回転数の上限値あるいは下限値とすることによっても、交流励磁形発電電動機１の能力限度内で電力系統の過渡安定度の向上を実現できる。以下、具体的に説明する。
【００３９】
図７において、交流励磁形発電電動機１の制御装置には、動作遅延手段としての条件検出器３４、制御モード切換器３５、動揺抑制手段としての目標回転数変更器４０及び回転数偏差検出器４１が設けられている。条件検出器３４は、電力系統３が加速あるいは減速しつつあることを検出し、制御モード切換器３５及び目標回転数変更器４０に切換信号Ｓ９，Ｓ１０，Ｓ１１（詳細後述）を発信する。制御モード切換器３５は、通常は電力偏差検出器１４からの偏差ΔＰをｑ軸制御装置１５に与える。そして、切換信号Ｓ９を受信すると、回転数偏差検出器４１からの回転数の偏差ΔＮをｑ軸制御装置１５に与えるように切り換える。
【００４０】
目標回転数変更器４０は、通常の回転数制御時の目標値Ｎｒ、運転可能回転数の下限値Ｎｍｉｎ、運転可能回転数の上限値Ｎｍａｘを記憶しており、切換信号Ｓ１０、Ｓ１１に応じてこれらの値のうちの一つを選択して目標回転数Ｎｖとして回転数偏差検出器４１に出力する。回転数偏差検出器４１は、目標回転数Ｎｖと回転数Ｎとの偏差ΔＮを出力する。
その他の構成については、図１に示した実施の形態１と同様のものであるので、相当するものに同じ符号を付して説明を省略する。
【００４１】
常時は、制御モード切換器３５は電力偏差検出器１４からの偏差ΔＰを、ｑ軸制御装置１５に与えるように切り換えられている。ここで、条件検出器３４の動作を図８に基づいて説明する。電力系統３で事故が発生して事故発生信号Ｓ１が発信された後、交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが周波数ｆαよりも大きくなると、目標回転数を運転可能回転数の上限値Ｎｍａｘに変更するように、目標回転数変更器４０に変更指令Ｓ１０を発信する。同時に、制御モード切換器３５に信号Ｓ９を出して回転数制御モード側、すなわち回転数偏差検出器４１側に切り換える。
【００４２】
逆に、交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇがｆβよりも小さくなったとき、つまり電力系統が減速したときは、信号Ｓ１１を発信して目標回転数変更器４０により目標回転数Ｎｖを回転数の下限値Ｎｍｉｎに変更するとともに、信号Ｓ９を出して制御モード切換器３５を回転数偏差検出器４１側に切換える。これにより電力系統３が加速しているときには上限値Ｎｍａｘ、電力系統が減速しているときには下限値Ｎｍｉｎに制御することができる。
【００４３】
つまり、電力系統が加速しているときに交流励磁形発電電動機１の出力を低下させる方向の制御、電力系統が減速しているときに交流励磁形発電電動機１の出力を増加させる方向の制御となり、電力系統の加速あるいは減速を抑制し過渡安定度を向上させることができる。
【００４４】
なお、以上は回転数制御にて説明したが、すべり制御であっても同様の効果を得ることができる。また、以上は電力系統の事故発生前はｑ軸制御を電力偏差検出器１４からの偏差ΔＰに基づいて制御しているものを説明したが、常に回転数あるいはすべりに基づいてｑ軸制御をしているものであってもよい。この場合は、制御モードの切換は不要であり、回転数あるいはすべりの目標値だけを変更することにより同様の効果が得られる。
【００４５】
また、以上では目標回転数Ｎｖを上限あるいは下限の回転数Ｎｍａｘ，Ｎｍｉｎに切り換えるものを示したが、この目標回転数Ｎｖを固定子巻線電圧の周波数ｆｇの上昇速度あるいは低下速度に応じて例えば比例させて変更するようにしても同様の効果を奏する。
【００４６】
実施の形態４．
図９〜図１１は、さらにこの発明の他の実施の形態を示すものであり、図９は交流励磁形発電電動機の制御装置の構成図である。図１０は図９の変換器制御装置の励磁周波数切換器の構成図、図１１は図９の周波数切換条件検出器のロジック回路図である。上記実施の形態３では、回転数制御に切り換える方式を示したが、電力変換器４の出力周波数、つまり交流励磁形発電電動機１の回転子の励磁周波数を変更しても同様な効果を得ることができる。図９は、この場合の構成を示し、変換制御装置１０６は、励磁周波数切換器１０６ａを有する。また、動作遅延手段としての周波数切換条件検出器４２が設けられている。なお、周波数切換条件検出器４２及び励磁周波数切換器１０６ａが、この発明における動揺抑制手段として作用する。
【００４７】
この実施の形態における励磁周波数切換器１０６ａは、図１の変換器制御装置６のすべり周波数制御器６ａの代わりに設けられたものである。図１０に示すように、励磁周波数切換器１０６ａは切換スイッチ１０６ｂを有し、励磁周波数を実すべり周波数ｆｓ１、マイナスすべり最大周波数値ｆｓ２、プラスすべり最大周波数値ｆｓ３に切換えることができる。
【００４８】
図１１は、周波数切換条件検出器４２のロジック回路を示したものであり、系統事故検出器３２から事故発生信号Ｓ１が発信されていないときは、通常のすべり周波数制御を選択する信号Ｓ１５を発信する。電力系統で事故が発生し、電力系統が加速され、交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆαよりも大きくなったときはマイナスすべり最大周波数値ｆｓ２を選択する信号Ｓ１６を発信する。電力系統が減速され、交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆβ（但し、ｆβ＜ｆα）よりも小さくなったときはプラスすべり最大周波数値ｆｓ３を選択する信号Ｓ１７を発信する。この信号Ｓ１５，Ｓ１６，Ｓ１７を励磁周波数切換器１０６ａが受信して電力変換器４の出力周波数を変更する。
【００４９】
電力変換器４の周波数がマイナスすべり最大周波数値ｆｓ２に設定されると、交流励磁形発電電動機１は許容最大回転数になるよう回転数が増加、つまり有効電力を低下させる方向に変化する。プラスすべり最大周波数値ｆｓ３選択時はその逆に変化する。よって、実施の形態４と同様、電力系統の加速あるいは減速を迅速に抑制し、過渡安定度を向上させることができる。
【００５０】
なお、以上は電力変換器４の出力周波数の制御値をプラスすべり最大周波数値、マイナスすべり最大周波数値に切り換えるものを説明した。しかし、この出力周波数の制御値を固定子周波数の上昇速度あるいは低下速度に応じて、例えば比例させて、プラスすべり最大周波数値あるいはマイナスすべり最大周波数値の方向に変更するものであっても、同様な効果が得られる。
【００５１】
実施の形態５．
図１２、図１３はさらにこの発明の他の実施の形態を示すものであり、図１２は交流励磁形発電電動機の制御装置の構成図、図１３は図１２の加減速抑制信号発生器の構成図である。以上に説明した実施の形態１〜４は、電力系統で事故が発生し、事故が除去された後の第一波の加減速を不要な抑制動作を行うことなく迅速に抑制し電力系統の過渡安定度を向上させることのできる制御装置に関するものである。しかし、第一波以降も電力系統の加減速による周波数変動が継続する場合がある。
【００５２】
このようなときに、図１における加減速抑制信号発生器３３の代わりに、図１２及び図１３に示す加減速抑制信号発生器２３３を設けることにより電力系統の動揺を速やかに収束させることができる。加減速抑制信号発生器２３３は、図１３に示すように、動作遅延手段としてのスイッチ制御回路２３３ａ、偏差検出器２３３ｂ、動揺抑制手段としての位相補正回路２３３ｃ、開閉スイッチ２３３ｄを有している。偏差検出器２３３ｂは、定格周波数ｆ０と、交流励磁形発電電動機１の固定子巻線電圧Ｖｇの周波数ｆｇとの偏差Δｆを出力し、この偏差Δｆを位相補正回路２３３ｃにて位相補正した信号を、開閉スイッチ２３３ｄを介して電力偏差検出器１４に与えるように構成されている。
【００５３】
図１３において、常時は、開閉スイッチ２３３ｄが開放している。電力系統３で事故が発生した場合は、スイッチ制御回路２３３ａが動作し、事故発生信号Ｓ１が発信されていて、かつ電力系統が加速して交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆαよりも大きくなったときに、開閉スイッチ２３３ｄを閉成して位相補正された信号Ｓ２０を電力偏差検出器１４（図１２）に与える。これにより、周波数の偏差に応じてｑ軸制御を変化させて電力系統の加減速を抑制する。
【００５４】
その後、交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが、別の所定の周波数ｆγ（但し、ｆγ＜ｆα、例えばｆα＝ｆ０＋Δｆ４に設定する、Δｆ４は所定値）を下回った状態、及び交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆδ（但し、ｆδ＜ｆβ、例えばｆβ＝ｆ０−Δｆ４に設定する、Δｆ４は所定値）を上回った状態が所定時間継続したときに、電力系統の過渡的な動揺が収束したと判断し、スイッチ制御回路２３３ａにより開閉スイッチ２３３ｄを開放して電力偏差検出器１４へ信号Ｓ２０を出力しないようにする。
【００５５】
電力系統３で事故が発生し事故発生信号Ｓ１が発信されていて、かつ電力系統が減速して交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが所定の周波数ｆβ（但し、ｆβ＜ｆα）よりも小さくなったときも、同様に開閉スイッチ２３３ｄを閉成して位相補正された信号Ｓ２０を電力偏差検出器１４（図１２）に与える。これにより、周波数の偏差に応じてｑ軸制御を変化させて電力系統の加減速を抑制する。
【００５６】
位相補正は、電力系統の特性、当該交流励磁形発電電動機の制御系及び交流励磁形発電電動機自身の時定数などを考慮し、電力系統の加減速抑制に最適なタイミングで制御するためのものである。なお、この実施の形態において、有効電力を制御する代わりに、交流励磁形発電電動機１の回転数又はすべり周波数を制御しても同様の効果を奏する。
以上により、電力系統の加減速による動揺が事故除去後も継続するような場合でも、速やかに電力系統の加減速を収束させ、電力系統の安定度を向上させることができる。
【００５７】
実施の形態６．
図１４は、さらにこの発明の他の実施の形態を示す交流励磁形発電電動機の制御装置の構成図である。実施の形態１や２では、回転エネルギーなどから求めた時間の間、電力系統の加速あるいは減速を抑制するための抑制信号を継続させるものを示した。しかし、例えば電力系統の加速抑制制御中に電力系統３が減速域となった後もこの制御を継続させると逆に減速を拡大させる。
【００５８】
この実施の形態においては、図１４のように抑制制御解除器４６を設ける。抑制制御解除器４６は、周波数検出器３０から交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇを得て、周波数ｆｇと定格周波数ｆ０との差の絶対値｜ｆｇ−ｆ０｜が所定値Δｆ１を下回るようになったとき、加減速抑制制御器３３からの信号Ｓ６を遮断して抑制制御を解除する。このように、加速抑制制御により交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇが定格周波数付近に戻ってきたことを検出し抑制制御を解除することにより、上記のような過度な抑制制御を防止することができる。
【００５９】
この実施の形態では、図１に示した実施の形態の制御装置に抑制制御解除器４６を設けたものを示したが、実施の形態２〜５に示したものに抑制制御解除器４６を設けても同様の効果を奏する。
【００６０】
実施の形態７．
図１５、図１６は、さらにこの発明の他の実施の形態を示すもので、図１５は交流励磁形発電電動機の制御装置の構成図、図１６は図１５の有効電力制限器の構成図である。交流励磁形発電電動機１は運転可能な出力範囲を持っており、以上に示した各実施の形態１〜６における加減速抑制制御において、上記運転可能な出力範囲を超えた運転状態となる可能性がある。この実施の形態は、これを防止するためのものである。
【００６１】
図１５において、交流励磁形発電電動機１の制御装置には有効電力制限器４８が設けられ、有効電力検出器１２にて検出された有効電力Ｐｇに基づいてｑ軸制御装置１５へ電力制御のための制御信号Ｓ３１を発信する。ｑ軸制御装置１５は、上記制御信号Ｓ３１に従って交流励磁形発電電動機１の電力を制御する。有効電力制限器４８は、図１６に示すように対上限偏差検出器４８ａ、対下限偏差検出器４８ｂ、高値選択器４８ｃ、低値選択器４８ｄを有する。有効電力制限器４８には、電圧偏差検出器１４から偏差ΔＰが、有効電力検出器１２から有効電力ｐｇが入力される。
【００６２】
対上限偏差検出器４８ａは、有効電力検出器１２からの有効電力ｐｇと交流励磁形発電電動機１の運転可能な有効電力の上限値Ｐｍａｘとの偏差ΔＰ１を求める。対下限偏差検出器４８ｂは、有効電力検出器１２からの有効電力ｐｇと交流励磁形発電電動機１の運転可能な有効電力の下限値Ｐｍａｘとの偏差ΔＰ２を求める。
【００６３】
高値選択器４８ｃは、偏差ΔＰと偏差ΔＰ２とを比較し、高い方の値を低値選択器４８ｄに出力する。低値選択器４８ｄは、高値選択器４８ｃからの出力と偏差ΔＰ１とを比較し低い方の値を選択し、制御信号Ｓ３１として、ｑ軸制御装置１５に出力する。ｑ軸制御装置１５は、この制御信号Ｓ３１に基づき交流励磁形発電電動機１の有効電力を制御する。
【００６４】
これにより、交流励磁形発電電動機１が有効電力の上限値Ｐｍａｘと下限値Ｐｍｉｎとの間で運転されているときは、高値選択器４８ｃ、低値選択器４８ｄとも偏差ΔＰの方を選択するため、制御信号Ｓ３１として偏差ΔＰがそのまま出力される。そして、交流励磁形発電電動機１の有効電力ＰｇがＰｍａｘより大きくなったとすると、有効電力と上限値Ｐｍａｘとの偏差ΔＰ１はマイナス（負）、有効電力Ｐｇと下限値Ｐｍｉｎとの偏差ΔＰ２もマイナス（負）となる。一方、有効電力Ｐｇが増加していることから偏差ΔＰは有効電力を増加させる方向のプラスであり、高値選択器４８ｃでは高い方の値である偏差ΔＰが選択される。
【００６５】
低値選択器４８ｄでは、低い方の値である有効電力Ｐｇと上限値Ｐｍａｘとの偏差ΔＰ１が選択される。従って、制御信号Ｓ３１として偏差ΔＰ１が選択され、有効電力を抑制する方向に制御される。最終的には偏差零つまり有効電力が上限値Ｐｍａｘに到達する。また、交流励磁形発電電動機１の有効電力Ｐｇが下限値Ｐｍｉｎより小さくなったときは、制御信号Ｓ３１として偏差ΔＰ２が出力される。そして、有効電力を増加する方向に制御され、最終的には有効電力が下限値Ｐｍｉｎまで回復する。
以上により、交流励磁形発電電動機１が許容範囲を超えて運転されるのを防止できる。
【００６６】
この実施の形態では、有効電力Ｐｇの大きさに応じて時限特性無しで有効電力の出力制限を行うものを示したが、交流励磁形発電電動機１の有する過負荷耐量を有効に活用するために所定時間所定量の過負荷を許容するように時限特性を持たせたようなものであってもよい。また、有効電力の代わりに固定子電流の制御を行う制限制御方式、有効電力以外に無効電力を加味してｄ、ｑ両軸の制限制御を行う方式、あるいは交流励磁形発電電動機１の運転可能な回転数範囲での運転となるよう回転数の制限制御を行う方式としてもよい。
【００６７】
この実施の形態では、図１の実施の形態の制御装置に有効電力制限器４８を設けたものを示したが、実施の形態２〜６に示したものに有効電力制限器４８を設けても同様の効果を奏する。
【００６８】
実施の形態８．
図１７は、さらにこの発明の他の実施の形態を示す原動機制御器の構成図である。図１７において、周波数調整用制御手段としての原動機制御器５０は、周波数偏差検出器５０ａ、原動機出力増減信号発信器５０ｂを有している。以上の各実施の形態においては、電力系統３の加減速を抑制する方式について示した。しかし、電力系統の加減速が収束した後、電力系統の需給バランスが崩れ、電源（供給）に比べ負荷（需要）の方が多いと周波数は低めで、逆だと高めで安定する。交流励磁形発電電動機１にポンプ水車などの原動機が接続されている場合は、図１７に示す原動機制御器５０（発電方向の例）を設けて、その出力を制御する。
【００６９】
原動機制御器５０は、その周波数偏差検出器５０ａにて定格周波数ｆ０と交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇとの偏差Δｆを求めて原動機出力増減信号発信器５０ｂに与える。原動機出力増減信号発信器５０ｂは、偏差Δｆが所定値εよりも大きくなると原動機出力増の信号Ｓ４１を出力し、偏差Δｆが（−ε）よりも小さくなると原動機出力減の信号Ｓ４２を出力し、図示しない原動機の出力を制御する。これにより、交流励磁形発電電動機１の入力を調整し、その能力の範囲内で需給バランスの崩れを補償することができる。
【００７０】
実施の形態９．
図１８は、さらにこの発明の他の実施の形態を示す原動機制御器の構成図である。図１８において、すべり値調整用制御手段としての原動機制御器５１は、すべり値検出器５１ａ、原動機出力増減信号発信器５１ｂを有している。電力系統３の加減速が収束した後、電力系統の需給バランスを極力維持しようと制御した結果、交流励磁形発電電動機１がその可変周波数の上限あるいは下限での運転状態となる場合がある。この状態での運転の場合、次に電力系統での加減速が発生した場合、加速あるいは減速のどちらかの抑制制御ができない。そこで、この実施の形態においては、このような事態を防止するために、交流励磁形発電電動機１にポンプ水車などの原動機が接続されている場合は、図１８に示す原動機制御器（発電方向の例）５１を付加する。
【００７１】
原動機制御器５１は、そのすべり検出器５１ａにて交流励磁形発電電動機１の固定子巻線電圧の周波数ｆｇと回転数Ｎからすべり値Ｓを求めて原動機出力増減信号発信器５１ｂに与える。原動機出力増減信号発信器５１ｂは、すべり値Ｓが所定値Ｓｍよりも大きくなると原動機出力増の信号Ｓ４３を、すべり値Ｓが（−Ｓｍ）よりも小さくなると原動機出力減の信号Ｓ４４を出力し、図示しない原動機の出力を制御する。これにより、交流励磁形発電電動機１の入力を調整し、その能力の範囲内で交流励磁形発電電動機１がその可変周波数限度内での運転となるよう制御することが可能である。所定値Ｓｍを、例えば通常運用時の制御目標のすべり値に設定すると、すべり値が制御目標のすべり値になるように原動機の出力が制御される。
【００７２】
実施の形態１０．
図１９は、さらにこの発明の他の実施の形態を示す原動機制御器の構成図である。この実施の形態は、図１７に示した周波数を制御するための原動機制御器５０と図１８に示したすべり値を制御する原動機制御器５１との両者の機能を有するものである。図１９において、周波数及びすべり値調整用制御手段としての原動機制御器５４は、周波数偏差検出器５０ａ、原動機出力増減信号発信器５０ｂ、すべり検出器５１ａ、原動機出力増減信号発信器５１ｂ、ＯＲ回路５４ａ，５４ｂを有している。
【００７３】
ＯＲ回路５４ａは、偏差Δｆが所定値εより大きくなるか、すべり値Ｓが所定値Ｓｍより大きくなると原動機出力増の信号Ｓ４５を発し、原動機の出力を増加させる。ＯＲ回路５４ｂは、偏差Δｆが（−ε）よりも小さくなるか、すべり値Ｓが（−Ｓｍ）よりも小さくなると原動機出力減の信号Ｓ４５を発し、原動機の出力を減少させる。交流励磁形発電電動機１の能力の範囲内で、電力系統の周波数維持及び引き続き発生する事故に対する加減速抑制制御能力を確保することができる。
【００７４】
なお、実施の形態１〜７では交流励磁形発電電動機１の駆動装置には触れなかったが、本発明は、この駆動装置が水車／ポンプのような原動機／回転負荷であるシステムあるいは同期調相機のように駆動装置が無いシステムのどちらにも適用可能で、いずれにおいても同様の効果を奏する。
【００７５】
【発明の効果】
この発明に係る交流励磁形発電電動機の制御装置は、以上説明したように、固定子巻線が電力系統に接続されるとともに回転子巻線が可変周波数の電力変換器に接続された交流励磁形発電電動機を制御するものであって、固定子巻線の周波数を検出する周波数検出手段と、交流励磁形発電電動機の回転数を検出する回転数検出手段と、交流励磁形発電電動機の運転可能な回転数の上限値と下限値と回転数とに基づいて交流励磁形発電電動機の利用可能な回転エネルギーを求める手段と、電力系統の事故を検出する事故検出手段と、事故検出手段が電力系統の事故を検出したとき、利用可能な回転エネルギーに応じて電力変換器を介して交流励磁形発電電動機の有効電力を制御することにより電力系統の動揺を抑制する動揺抑制手段とを備えたものであるので、
利用可能な回転エネルギーを求め、電力系統の事故が検出されたとき、上記利用可能な回転エネルギーに応じて交流励磁形発電電動機の有効電力を制御することにより、交流励磁形発電電動機を停止することなく電力系統の過渡安定度を向上させることができる。
【００７６】
そして、固定子巻線が電力系統に接続されるとともに回転子巻線が可変周波数の電力変換器に接続された交流励磁形発電電動機を制御するものであって、固定子巻線の電圧の周波数を検出する周波数検出手段と、交流励磁形発電電動機の回転数を検出する回転数検出手段と、電力系統の事故を検出する事故検出手段と、事故検出手段が電力系統の事故を検出したとき、交流励磁形発電電動機の固定子巻線の電圧の周波数の変動に応じて交流励磁形発電電動機の運転可能な回転数の上限値又は下限値になるように電力変換器を介して交流励磁形発電電動機の回転数を制御することにより電力系統の動揺を抑制する動揺抑制手段とを備えたものであるので、
交流励磁形発電電動機の回転数が運転可能な回転数の上限値又は下限値になるように交流励磁形発電電動機の有効電力を増減することにより、交流励磁形発電電動機を停止することなく電力系統の過渡安定度を向上させることができる。
【００７７】
さらに、固定子巻線が電力系統に接続されるとともに回転子巻線が可変周波数の電力変換器に接続された交流励磁形発電電動機を制御するものであって、固定子巻線の電圧の周波数を検出する周波数検出手段と、交流励磁形発電電動機の回転数を検出する回転数検出手段と、交流励磁形発電電動機の固定子巻線の電圧の周波数と回転数からすべり周波数を求める手段と、電力系統の事故を検出する事故検出手段と、事故検出手段が電力系統の事故を検出したとき、交流励磁形発電電動機の固定子巻線の電圧の周波数の変動に応じてすべり周波数が交流励磁形発電電動機の回転子の励磁可能な励磁周波数の上限値又は下限値になるように電力変換器の出力周波数を制御することにより電力系統の動揺を抑制する動揺抑制手段とを備えたものであるので、
すべり周波数が交流励磁形発電電動機の回転子の励磁可能な励磁周波数の上限値又は下限値になるように電力変換器の出力周波数を制御することにより、交流励磁形発電電動機を停止することなく電力系統の過渡安定度を向上させることができる。
【００７８】
また、固定子巻線が電力系統に接続されるとともに回転子巻線が可変周波数の電力変換器に接続された交流励磁形発電電動機を制御するものであって、固定子巻線の電圧の周波数を検出する周波数検出手段と、交流励磁形発電電動機の固定子巻線の電圧の周波数と基準となる所定の周波数との周波数偏差を検出して所定の位相補正する位相補正手段と、電力系統の事故を検出する事故検出手段と、事故検出手段が電力系統の事故を検出したとき、交流励磁形発電電動機の固定子巻線の電圧の周波数の変動に応じて位相補正された周波数偏差に基づき電力変換器を介して交流励磁形発電電動機の有効電力又は回転数又はすべり周波数を制御することにより電力系統の動揺を抑制する動揺抑制手段とを備えたものであるので、
位相補正された周波数偏差に基づき交流励磁形発電電動機の有効電力又は回転数又はすべり周波数を制御することにより、交流励磁形発電電動機を停止することなく電力系統の過渡安定度を向上させることができる。
【図面の簡単な説明】
【図１】この発明の実施の一形態である交流励磁形発電電動機の制御装置の構成図である。
【図２】図１の加減速抑制信号発生器の構成図である。
【図３】図１の系統事故検出器のロジック回路図である。
【図４】図２の事故時抑制指令信号発信手段のロジック回路図である。
【図５】この発明の他の実施の形態である交流励磁形発電電動機の制御装置の構成図である。
【図６】図５の加減速抑制信号発生器の構成図である。
【図７】さらに、この発明の他の実施の形態である交流励磁形発電電動機の制御装置の構成図である。
【図８】図７の条件検出器のロジック回路図である。
【図９】さらに、この発明の他の実施の形態である交流励磁形発電電動機の制御装置の構成図である。
【図１０】図９の変換器制御装置の励磁周波数切換器の構成図である。
【図１１】図９の周波数切換条件検出器のロジック回路図である。
【図１２】さらに、この発明の他の実施の形態である交流励磁形発電電動機の制御装置の構成図である。
【図１３】図１２の加減速抑制信号発生器のロジック回路及び構成図である。
【図１４】さらに、この発明の他の実施の形態を示す交流励磁形発電電動機の制御装置の構成図である。
【図１５】この発明の他の実施の形態である交流励磁形発電電動機の制御装置の構成図である。
【図１６】図１５の有効電力制限器の構成図である。
【図１７】さらに、この発明の他の実施の形態を示す原動機制御器の構成図である。
【図１８】さらに、この発明の他の実施の形態を示す原動機制御器の構成図である。
【図１９】さらに、この発明の他の実施の形態を示す原動機制御器の構成図である。
【符号の説明】
１ 交流励磁形発電電動機、３ 電力系統、４ 電力変換器、
６ 変換器制御装置、７ 位相及び回転数検出器、８ 電圧検出器、
９ 制御目標電圧設定器、１０ 電圧偏差検出器、１１ ｄ軸制御装置、
１２ 有効電力検出器、１３ 制御目標有効電力設定器、
１４ 電力偏差検出器、１５ ｑ軸制御装置、３０ 周波数検出器、
３１ 電流検出器、３２ 系統事故検出器、３３ 加減速抑制信号発生器、
３３ｂ 事故時抑制指令信号発信手段、
３３ｃ 利用可能回転エネルギー計算手段、３３ｅ 制御継続時間設定手段、
３３ｆ 有効電力計算手段、３３ｇ 抑制信号生成手段、３４ 条件検出器、
３５ 制御モード切換器、４０ 目標回転数変更器、４１ 回転数偏差検出器、
４２ 周波数切換条件検出器、４４ 周波数変化率検出器、４５ 位相補正器、
４６ 抑制制御解除器、４８ 有効電力制限器、
５０，５１，５４ 原動機制御器、１０６ 変換器制御装置、
１０６ａ 励磁周波数切換器、１３３ 加減速抑制信号発生器、
１３３ｆ 制御可能有効電力計算手段、１３３ｅ 制御継続時間計算手段、
１３３ｇ 抑制信号生成手段、２３３ 加減速抑制信号発生器、
２３３ｃ 位相補正回路。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for an AC excitation generator motor, and more particularly to a control device for an AC excitation generator motor that can improve the transient stability of a power system.
[0002]
[Prior art]
In a power system, when a large disturbance such as a one-wire ground fault or a three-phase short circuit occurs, synchronization may be lost due to an imbalance between mechanical energy input to the generator and power energy output from the generator to the transmission system. The degree to which power transmission can be stably maintained without being out of synchronization when a large system disturbance occurs is called transient stability, and the period of fluctuation from the first wave to the second wave that occurs after the occurrence of a system fault is targeted. .
In order to ensure the transient stability of the electric power system at this time, there is a method of stopping a generator designated in advance for the purpose of power supply limitation (see, for example, Non-Patent Document 1).
[0003]
[Non-Patent Document 1]
IEEJ Technical Report (Part II) No. 238 Power System Stabilization Technology Published by the Institute of Electrical Engineers of Japan, December 1986, pages 20, 94 and 4.3
[0004]
[Problems to be solved by the invention]
In the conventional method of stopping the generator, in order to return the power system to stop the generator, it is necessary to again parallel the generator to the power system. For this reason, there is a problem that it takes time to recover, or the generator has already been stopped after the transient fluctuation has been settled, so that the supply-demand balance is lost and the frequency of the power system is lowered. In addition, when detecting the conditions for stopping or controlling the generator on the power system side, particularly when the distance between the control device of the generator and the power system is a few kilometers, signal transmission delay, signal quality degradation, There were problems such as an increase in construction costs.
[0005]
An object of the present invention is to solve the above-mentioned problems and to obtain a control device for an AC excitation generator / motor that can improve the transient stability of an electric power system without stopping the AC excitation generator / motor. And
[0006]
[Means for Solving the Problems]
A control device for an AC excitation generator / motor according to the present invention controls an AC excitation generator / motor having a stator winding connected to a power system and a rotor winding connected to a variable frequency power converter. The frequency detection means for detecting the frequency of the stator winding, the rotation speed detection means for detecting the rotation speed of the AC excitation generator motor, the upper limit value of the operable rotation speed of the AC excitation generator motor, Means for determining the available rotational energy of the AC excitation generator motor based on the lower limit value and the rotational speed; an accident detection means for detecting an accident in the power system; and when the accident detection means detects an accident in the power system, According to the present invention, there is provided vibration suppression means for suppressing the fluctuation of the electric power system by controlling the effective power of the AC excitation type generator motor through the power converter in accordance with the available rotational energy.
[0007]
The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter for controlling an AC excitation generator motor, and the frequency of the stator winding voltage is controlled. When detecting an accident in the power system, the frequency detection means for detecting, the rotation speed detection means for detecting the rotation speed of the AC excitation type generator motor, the accident detection means for detecting an accident in the power system, AC excitation type power generation via a power converter so that the upper limit value or lower limit value of the operable speed of the AC excitation type generator motor can be reached according to the frequency fluctuation of the stator winding voltage of the AC excitation type generator motor. The apparatus includes a vibration suppression unit that suppresses the fluctuation of the electric power system by controlling the rotation speed of the electric motor.
[0008]
Furthermore, the stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation generator-motor. A frequency detecting means for detecting the rotational speed of the AC excitation type generator motor, a means for detecting the rotational frequency of the AC excitation type generator motor, a means for obtaining a slip frequency from the frequency of the stator winding voltage and the rotational speed of the AC excitation type generator motor, Accident detection means for detecting an accident in the power system, and when the accident detection means detects an accident in the power system, the slip frequency is changed to the AC excitation type according to the fluctuation of the frequency of the stator winding voltage of the AC excitation generator motor. A fluctuation suppression means for suppressing fluctuations in the electric power system by controlling the output frequency of the power converter so as to be the upper limit value or the lower limit value of the excitation frequency that can be excited by the rotor of the generator motor. .
[0009]
The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation generator-motor. A frequency detecting means for detecting the frequency, a phase correcting means for detecting a frequency deviation between the frequency of the stator winding voltage of the AC excitation type generator motor and a predetermined frequency as a reference, and correcting a predetermined phase; and Accident detection means for detecting an accident, and when the accident detection means detects an accident in the power system, the power is based on the frequency deviation phase-corrected according to the frequency fluctuation of the stator winding voltage of the AC excitation generator motor. The vibration suppression means suppresses the oscillation of the electric power system by controlling the effective power, the rotation speed, or the slip frequency of the AC excitation type generator motor via the converter.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram of a control device for an AC excitation generator motor, and FIG. 2 is a block diagram of an acceleration / deceleration suppression signal generator of FIG. FIG. 3 is a logic circuit diagram of the system fault detector of FIG. 1, and FIG. 4 is a logic circuit diagram of the fault suppression command signal transmitting means of FIG.
[0011]
In FIG. 1, an AC excitation generator motor 1 is connected to a power system 3 via a generator bus 25 and a step-up transformer 2. The variable frequency power converter 4 is connected to the generator bus 25 via the excitation transformer 5 and is supplied with power. The converter controller 6 includes a rotor current of the AC excitation generator 1 that has been transformed by an instrument current transformer (CT) 23, a phase and revolution detector 7 described later, a d-axis controller 11, The power converter 4 is controlled based on each signal input from the q-axis control device 15. The converter control device 6 has a slip frequency controller 6a. The slip frequency controller 6a detects the slip frequency fs of the AC excitation type generator motor 1, and controls the output frequency fe of the power converter 4 to be equal to the slip frequency fs.
[0012]
The phase and rotational speed detector 7 detects the rotational phase and rotational speed N of the rotor of the AC excitation type generator motor 1. The voltage detector 8 detects the stator voltage Vg of the AC excitation type generator motor 1 (generator bus 25) via the instrument transformer (PT) 22. The control target voltage setting unit 9 sets the control target voltage V0 of the stator voltage. The voltage deviation detector 10 detects a deviation ΔV between the control target voltage V 0 set by the control target voltage setter 9 and the stator voltage Vg detected by the voltage detector 8. The d-axis control device 11 gives a control command value for the d-axis component to the converter control device 6 based on the deviation ΔV detected by the voltage deviation detector 10.
[0013]
The active power detector 12 includes a stator voltage of the AC excitation type generator motor 1 transformed by the PT 22 and a current of the stator of the AC excitation type generator motor 1 transformed by the instrument current transformer (CT) 21. Based on the above, the effective power Pg of the stator of the AC excitation type generator motor 1 is detected. The CT 21 and PT 22 are a generator bus 25 on the low voltage side of the step-up transformer 2 and an AC excitation type generator motor in order to reduce the manufacturing cost and shorten the transmission distance of the detected signal. 1 is provided near.
[0014]
The control target active power setting unit 13 sets the control target active power P0. The power deviation detector 14 detects a deviation ΔP between the control target active power P 0 set by the control target active power setter 13 and the active power Pg detected by the active power detector 12. The q-axis control device 15 gives a control command value of the q-axis component to the converter control device 6 by output based on the deviation ΔP detected by the power deviation detector 14.
[0015]
The frequency detector 30 detects the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 through the PT 22. The system fault detector 32 detects the occurrence of an accident in the power system 3 based on the output Vg of the voltage detector 8, the output Pg of the active power detector 12, and the output Jg of the current detector 31, and generates an accident occurrence signal S1. To emit.
[0016]
As shown in FIG. 2, the acceleration / deceleration suppression signal generator 33 includes an accident time suppression command signal transmission means 33a, upper and lower limit rotation speed setting means 33b, usable rotational energy calculation means 33c, and control duration setting. Means 33e, active power value calculation means 33f, and suppression signal generation means 33g as fluctuation suppression means. This acceleration / deceleration suppression signal generator 33 is a suppression signal that suppresses acceleration or deceleration of the power system in order to improve the transient stability of the power system when the accident occurrence signal S1 is transmitted from the system accident detector 32. S6 is generated.
[0017]
Next, the operation will be described. First, the system fault detector 32 operates with a logic circuit as shown in FIG. For example, when a three-phase ground fault occurs in the power system 3, the voltage at the ground fault point is close to zero, and the stator voltage Vg of the AC excitation type generator motor 1 is changed from the AC excitation type generator motor 1 to the ground fault point. It decreases according to the distance to the terminal, that is, impedance. Further, the AC excitation type generator motor 1 is in a state of supplying a current in which the reactive component is dominant to the ground fault point, the active power Pg decreases, and the stator current Jg increases.
[0018]
As shown in FIG. 3, the logic by which the system fault detector 32 transmits the fault occurrence signal S1 uses the above-mentioned characteristics, and the stator voltage Vg of the AC excitation generator motor 1 is higher than the predetermined voltage Vα. It is detected that an accident has occurred in the power system due to the three conditions of decrease, active power Pg falling below a predetermined value ΔPg and suddenly decreasing, and stator current Jg exceeding Jα. An accident occurrence signal S1 is generated.
[0019]
Although an example of a combination of three conditions is shown here, only the stator voltage Vg of the AC excitation type generator motor 1 or any of the stator voltage Vg, power deviation ΔP, and stator current Jg. This can also be realized by combining the two.
[0020]
Next, the operation of the acceleration / deceleration suppression signal generator 33 in FIG. 2 will be described. In the case of the AC excitation type generator-motor 1, the frequency range of the AC excitation of the rotor, that is, the operable rotation speed range of the AC excitation-type generator motor 1 may be limited from the viewpoint of the economical efficiency of the equipment. If a uniform acceleration suppression signal or deceleration suppression signal is added when the operable speed range is limited as described above, there is a possibility that the operating range deviates from the operable speed range.
[0021]
The acceleration / deceleration suppression signal generator 33 absorbs excess active power in the power system 3 as its rotational energy within the maximum allowable range of the AC excitation type generator motor 1, or converts the insufficient active power into its rotational energy. The AC excitation type generator motor 1 is controlled so as to be discharged from. As a result, the vibration of the electric system when an accident occurs in the electric power system 3 is quickly absorbed to improve the transient stability, and the AC excitation type generator motor 1 enters the operating range deviating from the operable speed range. To prevent. Hereinafter, the operation will be described in detail.
[0022]
In FIG. 2, an accident suppression command signal transmission means 33a receives an accident occurrence signal S1 transmitted when the system fault detector 32 detects an accident in the power system 3, and generates an accident as shown in the logic circuit diagram of FIG. The accident occurrence signal S1 is held for a predetermined time by the off-delay timer even after the motor is removed until the frequency fg of the stator winding voltage of the power system 3, that is, the AC excitation generator motor 1, exceeds the predetermined frequency fα. (Fg> fα) When an acceleration occurs, or when the frequency fg of the stator winding voltage is decelerated until the frequency fg falls below a predetermined frequency fβ (where fβ <fα), an accident suppression command signal S2 is transmitted. .
[0023]
The accident suppression command signal transmission means 33a as the operation delay means generates the accident suppression command signal S2 after the frequency fg of the stator winding voltage exceeds the frequency fα or falls below the frequency fβ in the event of an accident. This is to prevent unnecessary suppression operations immediately after an accident.
[0024]
When the available rotation energy calculation means 33c receives the accident suppression command signal S2 from the accident suppression command signal transmission means 33a, it calculates the available rotational energy as follows.
Below, the case where surplus electric power is absorbed by increasing the rotation speed of AC excitation type generator motor 1 is demonstrated.
[0025]
The rotational energy E1 possessed by the rotor rotating at the rotational speed N is I (kg · m), where the inertial performance rate of the AC excitation generator motor 1 is I (kg · m).

Is required. Therefore, if the upper limit value of the operable rotational speed is Nmax, the rotational energy ΔE when the rotational speed changes from N to Nmax can be obtained by Expression (2).

[0026]
Rotational energy ΔE is a unit of W · second. If t is the control duration of acceleration suppression determined by simulation calculation or the like, the possible control amount ΔPc of active power at this time is
ΔPc = ΔE / t (3)
It is obtained by The active power value calculating unit 33f calculates ΔPc based on the above equation (3) from the control duration t set in advance in the control duration setting unit 33e and ΔE.
Based on this, the suppression signal S6 generated by the suppression signal generation means 33g is applied to the active power for a certain time t as shown in the frame of the suppression signal generation means 33g in FIG. 2 by the function of ΔPc, t. By setting the signal to decrease by ΔP, it is possible to realize acceleration / deceleration suppression control of the electric power system within the allowable operating limit without excessively controlling the AC excitation type generator motor 1.
[0027]
Specifically, as shown in FIG. 1, the suppression signal S6 is added to the power deviation detector 14, thereby controlling the active power in the direction of decreasing and suppressing the acceleration of the power system. That is, since the power system is accelerated in the state of power generation amount> load (demand) amount, the generated active power is reduced and absorbed as the rotational energy of the AC excitation generator motor 1 to accelerate the power system. Can be suppressed.
[0028]
When an accident occurs in the power system 3, an accident occurrence signal S1 is output from the system fault detector 32, and the fault suppression command signal transmission means 33a has a predetermined frequency fg of the stator winding voltage of the AC excitation generator motor 1. When the frequency fα is exceeded, an accident suppression command signal S2 is issued. After receiving the accident suppression command signal S2, the available rotational energy calculation means 33c, the active power value calculation means 33f, and the suppression signal generation means 33g operate as described above and transmit the suppression signal S6.
[0029]
The control when the power system is decelerated also detects that the frequency fg of the stator winding voltage is lower than the predetermined frequency fβ, and prevents the rotational speed of the AC excitation generator motor 1 from being lower than Nmin. However, the control is the same as that in the case where the power system is accelerated except that the rotational energy of the AC excitation generator motor 1 is released at the fastest speed and the effective power Pg is controlled to increase.
Moreover, although the above showed the example which controls active power as q-axis control, the same effect can be acquired even when the rotation speed or slip is controlled as q-axis control.
[0030]
In order to shorten the response time, instead of the available rotational energy calculating means 33c and the active power value calculating means 33f, for example, an active power value storage means is provided as means for obtaining available rotational energy, and this active power is provided. The value storage means stores the available rotational energy ΔE and the possible control amount ΔPc calculated in advance corresponding to the rotational speed as a table, and when the accident occurrence signal S1 is transmitted, refer to the table. It is also possible to read out the possible control amount ΔPc corresponding to the rotational speed N.
[0031]
As described above, according to this embodiment, the AC excitation obtained from the available rotational energy and the predetermined suppression duration time when the available rotational energy is obtained and an accident in the power system is detected. It can be used by increasing / decreasing the active power of the AC excitation type generator motor by the possible control amount of the active power of the AC generator motor, that is, by increasing / decreasing the effective power of the AC excitation type generator motor according to the available rotational energy. It is possible to quickly suppress the fluctuation of the power system without stopping the AC excitation type generator motor by utilizing the rotational energy to the maximum, and to improve the transient stability of the power system.
[0032]
Further, the effective power of the AC excitation generator motor 1 is based only on the information of various quantities of the AC excitation generator motor such as the stator winding voltage Vg, frequency fg, current Jg, and power Pg of the AC excitation generator motor 1. Can be controlled. Therefore, even when the distance between the control device of the AC excitation type generator motor and the power system is long, it is possible to prevent signal transmission delay, signal quality deterioration, construction cost increase, and the like.
[0033]
Embodiment 2. FIG.
5 and 6 show another embodiment of the present invention. FIG. 5 is a block diagram of a control device for an AC excitation generator motor, and FIG. 6 is a block diagram of an acceleration / deceleration suppression signal generator of FIG. It is. In this embodiment, an acceleration / deceleration suppression signal generator 133 is provided as shown in FIG. As shown in FIG. 6, the acceleration / deceleration suppression signal generator 133 includes a control duration calculation unit 133e, a controllable active power value calculation unit 133f, and a suppression signal generation unit 133g as a fluctuation suppression unit. Since other configurations are the same as those of the first embodiment shown in FIGS. 1 and 2, the same components are denoted by the same reference numerals, and description thereof is omitted.
[0034]
In the AC excitation generator motor 1, the range of effective power that can be operated is determined from the current capacity of the stator, the current capacity of the rotor, or the performance of the control device and power converter. Assuming that the maximum value of the operable active power is Pmax, the minimum value is Pmin, and the operating active power at that time is Pa, the available active power value is (Pmax−Pa) or (Pmin−Pa). . The controllable active power value calculating means 133f obtains (Pmax−Pa) or (Pmin−Pa). Let this be ΔPma.
[0035]
Next, the control duration calculation means 133e obtains the control duration t1 from this ΔPma and the available rotational energy ΔE shown in the above equation (2) as follows.
t1 = ΔE / ΔPma (4)
The suppression signal generation unit 133g makes the suppression signal S7 a signal for reducing the active power by ΔPma for a certain time t1, as shown in the frame of the suppression signal generation unit 133g of FIG. 6 by the function of ΔPma, t1. Thus, acceleration / deceleration suppression control within the allowable operation limit is performed without excessively controlling the AC excitation generator motor 1, and the transient stability of the power system at the time of the accident is ensured.
[0036]
Note that the available active power may be either a rated value for steady operation or a transient limit value expressed as a function of time as necessary.
Although not shown, if acceleration suppression control is continued even after the power system is decelerated by the acceleration / deceleration suppression control of the power system, there is a possibility that the deceleration of the power system is expanded and the power system becomes unstable. For this reason, the acceleration / deceleration suppression signal generator 133 detects that the frequency has changed, for example, at a constant time or a frequency change, for example, regardless of the control time t1 obtained by the above calculation, and this suppression control. An acceleration / deceleration suppression control stop device for stopping S7 is added.
[0037]
As described above, according to this embodiment, the control duration is obtained from the available rotational energy and the controllable active power value, and when a power system fault is detected, only the controllable active power value is AC-excited. Increase or decrease the effective power of the AC generator motor, that is, increase or decrease the AC power of the AC excitation type generator motor according to the available rotational energy. It is possible to quickly suppress the fluctuation of the power system without stopping the electric motor, and to improve the transient stability of the power system.
[0038]
Embodiment 3 FIG.
7 and 8 further show another embodiment of the present invention. FIG. 7 is a block diagram of a control device for an AC excitation type generator motor, and FIG. 8 is a logic circuit diagram of the condition detector of FIG. is there. Embodiments 1 and 2 described above are systems in which a signal for acceleration / deceleration suppression is added to the set value of the control target active power setting unit 13, but the acceleration / deceleration suppression control is shown in FIG. As described above, the control mode switching unit 35 switches the q-axis control to the rotational speed control, and the control target rotational speed is set to the upper limit value or the lower limit value of the operable rotational speed. Can improve the transient stability of the power system. This will be specifically described below.
[0039]
In FIG. 7, the control device for the AC excitation generator motor 1 includes a condition detector 34 as an operation delay means, a control mode switch 35, a target rotational speed changer 40 and a rotational speed deviation detector 41 as shake suppression means. Is provided. The condition detector 34 detects that the power system 3 is accelerating or decelerating, and transmits switching signals S9, S10, and S11 (details will be described later) to the control mode switching device 35 and the target rotational speed changing device 40. The control mode switch 35 normally gives the deviation ΔP from the power deviation detector 14 to the q-axis controller 15. When the switching signal S9 is received, switching is performed so that the rotational speed deviation ΔN from the rotational speed deviation detector 41 is given to the q-axis control device 15.
[0040]
The target rotational speed changer 40 stores a target value Nr during normal rotational speed control, a lower limit value Nmin of the operable rotational speed, and an upper limit value Nmax of the operable rotational speed, and according to the switching signals S10 and S11. One of these values is selected and output to the rotational speed deviation detector 41 as the target rotational speed Nv. The rotational speed deviation detector 41 outputs a deviation ΔN between the target rotational speed Nv and the rotational speed N.
Since other configurations are the same as those of the first embodiment shown in FIG. 1, the same reference numerals are given to the corresponding components and the description thereof is omitted.
[0041]
Normally, the control mode switch 35 is switched so as to give the deviation ΔP from the power deviation detector 14 to the q-axis controller 15. Here, the operation of the condition detector 34 will be described with reference to FIG. When the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 becomes higher than the frequency fα after the accident has occurred in the power system 3 and the accident occurrence signal S1 has been transmitted, the target rotational speed can be set to the operational rotational speed. The change command S10 is transmitted to the target rotation speed changer 40 so as to change to the upper limit value Nmax. At the same time, a signal S9 is output to the control mode switch 35 to switch to the rotation speed control mode side, that is, the rotation speed deviation detector 41 side.
[0042]
Conversely, when the frequency fg of the stator winding voltage of the AC excitation generator motor 1 becomes smaller than fβ, that is, when the power system is decelerated, a signal S11 is transmitted and the target rotation speed changer 40 sets the target. The engine speed Nv is changed to the engine speed lower limit value Nmin, and a signal S9 is issued to switch the control mode switch 35 to the engine speed deviation detector 41 side. Thus, the upper limit value Nmax can be controlled when the power system 3 is accelerating, and the lower limit value Nmin can be controlled when the power system is decelerating.
[0043]
That is, the control in the direction to decrease the output of the AC excitation type generator motor 1 when the power system is accelerating, and the control in the direction to increase the output of the AC excitation type generator motor 1 when the power system is decelerating. In addition, acceleration or deceleration of the power system can be suppressed and transient stability can be improved.
[0044]
In addition, although the above demonstrated in rotation speed control, the same effect can be acquired even if it is slip control. In the above description, the q-axis control is controlled based on the deviation ΔP from the power deviation detector 14 before the occurrence of an accident in the power system. However, the q-axis control is always performed based on the rotational speed or the slip. It may be. In this case, it is not necessary to switch the control mode, and the same effect can be obtained by changing only the rotation speed or the target value of the slip.
[0045]
In the above description, the target rotation speed Nv is switched to the upper limit or lower limit rotation speeds Nmax and Nmin. The target rotation speed Nv is set according to the speed of increase or decrease of the frequency fg of the stator winding voltage, for example. Even if it is changed in proportion, the same effect is obtained.
[0046]
Embodiment 4 FIG.
9 to 11 further show another embodiment of the present invention, and FIG. 9 is a block diagram of a control device for an AC excitation type generator motor. FIG. 10 is a block diagram of the excitation frequency switch of the converter control device of FIG. 9, and FIG. 11 is a logic circuit diagram of the frequency switch condition detector of FIG. In the third embodiment, the method of switching to the rotational speed control is shown, but the same effect can be obtained even if the output frequency of the power converter 4, that is, the excitation frequency of the rotor of the AC excitation generator motor 1 is changed. Can do. FIG. 9 shows a configuration in this case, and the conversion control device 106 includes an excitation frequency switch 106a. Further, a frequency switching condition detector 42 is provided as an operation delay means. The frequency switching condition detector 42 and the excitation frequency switching unit 106a function as the vibration suppressing means in the present invention.
[0047]
The excitation frequency switch 106a in this embodiment is provided in place of the slip frequency controller 6a of the converter controller 6 of FIG. As shown in FIG. 10, the excitation frequency switch 106a has a changeover switch 106b, and can switch the excitation frequency to the actual slip frequency fs1, the minus slip maximum frequency value fs2, and the plus slip maximum frequency value fs3.
[0048]
FIG. 11 shows a logic circuit of the frequency switching condition detector 42. When the fault occurrence signal S1 is not transmitted from the system fault detector 32, a signal S15 for selecting normal slip frequency control is transmitted. To do. When an accident occurs in the power system, the power system is accelerated, and the frequency fg of the stator winding voltage of the AC excitation generator motor 1 becomes higher than the predetermined frequency fα, the minus slip maximum frequency value fs2 is selected. Signal S16 is transmitted. When the power system is decelerated and the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 becomes smaller than a predetermined frequency fβ (where fβ <fα), a signal for selecting the plus slip maximum frequency value fs3. Send S17. The excitation frequency switch 106a receives these signals S15, S16, S17 and changes the output frequency of the power converter 4.
[0049]
When the frequency of the power converter 4 is set to the minus-slip maximum frequency value fs2, the AC excitation type generator motor 1 increases in rotational speed so as to reach an allowable maximum rotational speed, that is, changes in a direction of reducing active power. When the plus slip maximum frequency value fs3 is selected, the change is reversed. Therefore, as in the fourth embodiment, acceleration or deceleration of the power system can be suppressed quickly, and transient stability can be improved.
[0050]
In the above description, the control value of the output frequency of the power converter 4 is switched between the plus slip maximum frequency value and the minus slip maximum frequency value. However, even if the control value of the output frequency is changed in the direction of the positive slip maximum frequency value or the negative slip maximum frequency value, for example, in proportion to the increase or decrease speed of the stator frequency, the same applies. Effects can be obtained.
[0051]
Embodiment 5. FIG.
12 and 13 further show another embodiment of the present invention. FIG. 12 is a block diagram of a control device for an AC excitation generator motor, and FIG. 13 is a block diagram of an acceleration / deceleration suppression signal generator of FIG. FIG. In the first to fourth embodiments described above, an accident occurs in the power system, and the acceleration / deceleration of the first wave after the accident is removed is quickly suppressed without performing unnecessary suppression operations, and the power system is transient. The present invention relates to a control device that can improve stability. However, frequency fluctuations due to acceleration / deceleration of the power system may continue even after the first wave.
[0052]
In such a case, by providing the acceleration / deceleration suppression signal generator 233 shown in FIGS. 12 and 13 instead of the acceleration / deceleration suppression signal generator 33 in FIG. 1, the fluctuation of the electric power system can be quickly converged. . As shown in FIG. 13, the acceleration / deceleration suppression signal generator 233 includes a switch control circuit 233a as an operation delay unit, a deviation detector 233b, a phase correction circuit 233c as an oscillation suppression unit, and an open / close switch 233d. The deviation detector 233b outputs a deviation Δf between the rated frequency f0 and the frequency fg of the stator winding voltage Vg of the AC excitation generator motor 1, and a signal obtained by correcting the phase of the deviation Δf by the phase correction circuit 233c. The power deviation detector 14 is configured to be supplied via the open / close switch 233d.
[0053]
In FIG. 13, the open / close switch 233d is normally open. When an accident occurs in the electric power system 3, the switch control circuit 233a operates, the accident occurrence signal S1 is transmitted, and the electric power system accelerates so that the frequency of the stator winding voltage of the AC excitation generator motor 1 is increased. When fg becomes larger than the predetermined frequency fα, the open / close switch 233d is closed and the phase-corrected signal S20 is supplied to the power deviation detector 14 (FIG. 12). Thereby, q-axis control is changed according to the frequency deviation to suppress acceleration / deceleration of the power system.
[0054]
Thereafter, the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 is lower than another predetermined frequency fγ (provided that fγ <fα, for example, fα = f0 + Δf4, Δf4 is a predetermined value), And a state in which the frequency fg of the stator winding voltage of the AC excitation generator motor 1 exceeds a predetermined frequency fδ (where fδ <fβ, for example, fβ = f0−Δf4, Δf4 is a predetermined value). When it continues, it is determined that the transient fluctuation of the power system has converged, and the switch control circuit 233a opens the open / close switch 233d so that the signal S20 is not output to the power deviation detector 14.
[0055]
An accident has occurred in the power system 3 and an accident signal S1 has been transmitted, and the power system has decelerated and the frequency fg of the stator winding voltage of the AC excitation generator motor 1 has a predetermined frequency fβ (provided that fβ < Similarly, when it becomes smaller than fα), the open / close switch 233d is closed and the phase-corrected signal S20 is given to the power deviation detector 14 (FIG. 12). Thereby, q-axis control is changed according to the frequency deviation to suppress acceleration / deceleration of the power system.
[0056]
Phase correction is for controlling at the optimal timing to suppress acceleration / deceleration of the power system, taking into consideration the characteristics of the power system, the control system of the AC excitation generator / motor and the time constant of the AC excitation generator / motor itself. is there. In this embodiment, the same effect can be obtained by controlling the rotational speed or slip frequency of the AC excitation generator motor 1 instead of controlling the active power.
As described above, even when the fluctuation due to acceleration / deceleration of the power system continues even after the accident is removed, the acceleration / deceleration of the power system can be quickly converged and the stability of the power system can be improved.
[0057]
Embodiment 6 FIG.
FIG. 14 is a block diagram of a control device for an AC excitation type generator-motor showing still another embodiment of the present invention. In Embodiments 1 and 2, the suppression signal for suppressing the acceleration or deceleration of the power system is continued for the time determined from the rotational energy or the like. However, for example, if this control is continued even after the power system 3 enters the deceleration region during the acceleration suppression control of the power system, the deceleration is increased.
[0058]
In this embodiment, a suppression control canceller 46 is provided as shown in FIG. The suppression control canceller 46 obtains the frequency fg of the stator winding voltage of the AC excitation generator motor 1 from the frequency detector 30, and the absolute value | fg−f0 | of the difference between the frequency fg and the rated frequency f0 is predetermined. When the value falls below the value Δf1, the signal S6 from the acceleration / deceleration suppression controller 33 is interrupted to cancel the suppression control. Thus, by detecting that the frequency fg of the stator winding voltage of the AC excitation generator motor 1 has returned to the vicinity of the rated frequency by the acceleration suppression control and canceling the suppression control, the excessive suppression as described above is performed. Control can be prevented.
[0059]
In this embodiment, the control device according to the embodiment shown in FIG. 1 is provided with the suppression control canceller 46. However, the suppression control canceller 46 is provided in the one shown in the second to fifth embodiments. However, the same effect can be obtained.
[0060]
Embodiment 7 FIG.
FIGS. 15 and 16 show still another embodiment of the present invention. FIG. 15 is a block diagram of a control device for an AC excitation generator motor, and FIG. 16 is a block diagram of an active power limiter in FIG. is there. The AC excitation generator motor 1 has an operable output range, and in the acceleration / deceleration suppression control in each of the first to sixth embodiments described above, there is a possibility that the operating state exceeds the operable output range. There is. This embodiment is for preventing this.
[0061]
In FIG. 15, an active power limiter 48 is provided in the control device of the AC excitation type generator motor 1, and the q-axis control device 15 performs power control based on the active power Pg detected by the active power detector 12. The control signal S31 is transmitted. The q-axis control device 15 controls the power of the AC excitation generator motor 1 in accordance with the control signal S31. As shown in FIG. 16, the active power limiter 48 includes an upper limit deviation detector 48a, a lower limit deviation detector 48b, a high value selector 48c, and a low value selector 48d. The active power limiter 48 receives the deviation ΔP from the voltage deviation detector 14 and the active power pg from the active power detector 12.
[0062]
The upper limit deviation detector 48 a obtains a deviation ΔP <b> 1 between the active power pg from the active power detector 12 and the upper limit value Pmax of active power operable by the AC excitation generator motor 1. The lower limit deviation detector 48b obtains a deviation ΔP2 between the active power pg from the active power detector 12 and the lower limit value Pmax of the active power operable by the AC excitation generator motor 1.
[0063]
The high value selector 48c compares the deviation ΔP and the deviation ΔP2, and outputs the higher value to the low value selector 48d. The low value selector 48d compares the output from the high value selector 48c with the deviation ΔP1, selects the lower value, and outputs it to the q-axis controller 15 as the control signal S31. The q-axis control device 15 controls the active power of the AC excitation generator motor 1 based on the control signal S31.
[0064]
Thereby, when the AC excitation type generator motor 1 is operated between the upper limit value Pmax and the lower limit value Pmin of the active power, both the high value selector 48c and the low value selector 48d select the deviation ΔP. The deviation ΔP is output as it is as the control signal S31. If the active power Pg of the AC excitation generator motor 1 is larger than Pmax, the deviation ΔP1 between the active power and the upper limit value Pmax is negative (negative), and the deviation ΔP2 between the active power Pg and the lower limit value Pmin is also negative ( Negative). On the other hand, since the active power Pg is increased, the deviation ΔP is a plus in the direction of increasing the active power, and the higher value selector 48c selects the higher deviation ΔP.
[0065]
The low value selector 48d selects the deviation ΔP1 between the active power Pg, which is the lower value, and the upper limit value Pmax. Therefore, the deviation ΔP1 is selected as the control signal S31, and the control is performed in a direction to suppress the active power. Eventually, the deviation is zero, that is, the active power reaches the upper limit value Pmax. When the active power Pg of the AC excitation generator motor 1 becomes smaller than the lower limit value Pmin, the deviation ΔP2 is output as the control signal S31. Then, the active power is controlled to increase, and finally the active power recovers to the lower limit value Pmin.
As described above, it is possible to prevent the AC excitation type generator motor 1 from operating beyond the allowable range.
[0066]
In this embodiment, the active power output is limited without a time characteristic depending on the magnitude of the active power Pg. However, in order to effectively utilize the overload capability of the AC excitation generator motor 1. It may have a time characteristic so as to allow a predetermined amount of overload for a predetermined time. In addition, a limit control method for controlling the stator current instead of the active power, a method for limiting the d and q axes by adding reactive power in addition to the active power, or the operation of the AC excitation generator motor 1 is possible. It is good also as a system which performs restriction | limiting control of rotation speed so that it may drive | operate in the rotation speed range.
[0067]
In this embodiment, the control device of the embodiment of FIG. 1 is provided with the active power limiter 48. However, the active power limiter 48 may be provided in the embodiment shown in the second to sixth embodiments. The same effect is produced.
[0068]
Embodiment 8 FIG.
FIG. 17 is a block diagram of a prime mover controller showing still another embodiment of the present invention. In FIG. 17, a prime mover controller 50 as a frequency adjustment control means includes a frequency deviation detector 50a and a prime mover output increase / decrease signal transmitter 50b. In each of the above embodiments, a method for suppressing acceleration / deceleration of the power system 3 has been described. However, after the acceleration / deceleration of the power system has converged, the supply and demand balance of the power system is disrupted, and the frequency is lower when the load (demand) is greater than the power supply (supply), and the frequency is lower and higher. When a prime mover such as a pump turbine is connected to the AC excitation generator motor 1, a prime mover controller 50 (an example of the power generation direction) shown in FIG. 17 is provided to control its output.
[0069]
The prime mover controller 50 obtains a deviation Δf between the rated frequency f0 and the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 by the frequency deviation detector 50a and supplies the deviation Δf to the prime mover output increase / decrease signal transmitter 50b. The prime mover output increase / decrease signal transmitter 50b outputs a prime mover output increase signal S41 when the deviation Δf becomes larger than a predetermined value ε, and outputs a prime mover output decrease signal S42 when the deviation Δf becomes smaller than (−ε). Controls the output of a motor (not shown). Thereby, the input of AC excitation type generator motor 1 can be adjusted, and the balance of supply-demand balance can be compensated for within the range of the capability.
[0070]
Embodiment 9 FIG.
FIG. 18 is a block diagram of a prime mover controller showing still another embodiment of the present invention. In FIG. 18, a prime mover controller 51 as a slip value adjusting control means has a slip value detector 51a and a prime mover output increase / decrease signal transmitter 51b. After the acceleration / deceleration of the power system 3 converges, the AC excitation generator motor 1 may be in an operating state at the upper limit or the lower limit of the variable frequency as a result of controlling to maintain the supply and demand balance of the power system as much as possible. In the case of operation in this state, when acceleration / deceleration occurs in the power system next time, it is impossible to perform suppression control of either acceleration or deceleration. Therefore, in this embodiment, in order to prevent such a situation, when a prime mover such as a pump turbine is connected to the AC excitation generator motor 1, the prime mover controller (in the direction of power generation) shown in FIG. Example) 51 is added.
[0071]
The prime mover controller 51 obtains a slip value S from the frequency fg of the stator winding voltage of the AC excitation type generator motor 1 and the rotational speed N by the slip detector 51a, and gives it to the prime mover output increase / decrease signal transmitter 51b. The prime mover output increase / decrease signal transmitter 51b outputs a prime mover output increase signal S43 when the slip value S becomes larger than the predetermined value Sm, and a prime mover output decrease signal S44 when the slip value S becomes smaller than (−Sm). Controls the output of a motor (not shown). Thereby, it is possible to adjust the input of the AC excitation type generator motor 1 and control the AC excitation type generator motor 1 to operate within the variable frequency limit within the range of the capacity. For example, when the predetermined value Sm is set to the slip value of the control target during normal operation, the output of the prime mover is controlled so that the slip value becomes the slip value of the control target.
[0072]
Embodiment 10 FIG.
FIG. 19 is a block diagram of a prime mover controller showing still another embodiment of the present invention. This embodiment has the functions of both the prime mover controller 50 for controlling the frequency shown in FIG. 17 and the prime mover controller 51 for controlling the slip value shown in FIG. In FIG. 19, a prime mover controller 54 as frequency and slip value adjustment control means includes a frequency deviation detector 50a, a prime mover output increase / decrease signal transmitter 50b, a slip detector 51a, a prime mover output increase / decrease signal transmitter 51b, an OR circuit 54a. , 54b.
[0073]
The OR circuit 54a generates a prime mover output increase signal S45 to increase the prime mover output when the deviation Δf is greater than the predetermined value ε or the slip value S is greater than the predetermined value Sm. When the deviation Δf is smaller than (−ε) or the slip value S is smaller than (−Sm), the OR circuit 54b generates a prime mover output decrease signal S45 to reduce the prime mover output. Within the range of the capability of the AC excitation generator motor 1, it is possible to maintain the frequency of the electric power system and to ensure acceleration / deceleration suppression control capability for a subsequent accident.
[0074]
In the first to seventh embodiments, the drive device for the AC excitation generator motor 1 was not touched, but the present invention is a system or a synchronous phase adjuster in which the drive device is a prime mover / rotary load such as a water turbine / pump. The present invention can be applied to either of the systems having no driving device as described above, and in either case, the same effect can be obtained.
[0075]
【The invention's effect】
As described above, the control device for an AC excitation generator / motor according to the present invention includes an AC excitation type in which a stator winding is connected to a power system and a rotor winding is connected to a variable frequency power converter. The generator motor is controlled, and a frequency detection means for detecting the frequency of the stator winding, a rotation speed detection means for detecting the rotation speed of the AC excitation type generator motor, and the AC excitation type generator motor can be operated. Means for obtaining available rotational energy of the AC excitation type generator motor based on the upper limit value, the lower limit value and the rotational speed of the rotational speed, an accident detecting means for detecting an accident in the electric power system, and an accident detecting means for the electric power system When detecting an accident, equipped with a vibration suppression means that suppresses the fluctuation of the power system by controlling the effective power of the AC excitation type generator motor via the power converter according to the available rotational energy Since it is is,
When the available rotational energy is determined and an accident in the power system is detected, the AC excited generator motor is stopped by controlling the active power of the AC excited generator motor according to the available rotational energy. Therefore, the transient stability of the power system can be improved.
[0076]
The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter for controlling an AC excitation generator motor, and the frequency of the stator winding voltage is controlled. Frequency detection means for detecting, rotation speed detection means for detecting the rotation speed of the AC excitation type generator motor, accident detection means for detecting an accident in the power system, and when the accident detection means detects an accident in the power system, AC excitation type power generation via a power converter so that the upper limit value or lower limit value of the operable speed of the AC excitation type generator motor can be reached according to the frequency fluctuation of the stator winding voltage of the AC excitation type generator motor. Since it is equipped with a vibration suppression means that suppresses the fluctuation of the power system by controlling the rotation speed of the electric motor,
Power system without stopping AC excitation type generator motor by increasing / decreasing effective power of AC excitation type generator motor so that rotation speed of AC excitation type generator motor becomes upper limit value or lower limit value of operable speed The transient stability of can be improved.
[0077]
Furthermore, the stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation generator-motor. A frequency detecting means for detecting the rotational speed of the AC excitation type generator motor, a means for detecting the rotational frequency of the AC excitation type generator motor, a means for obtaining a slip frequency from the frequency of the stator winding voltage and the rotational speed of the AC excitation type generator motor, Accident detection means for detecting an accident in the power system, and when the accident detection means detects an accident in the power system, the slip frequency is changed to the AC excitation type according to the fluctuation of the frequency of the stator winding voltage of the AC excitation generator motor. A fluctuation suppression means for suppressing fluctuations in the electric power system by controlling the output frequency of the power converter so as to be the upper limit value or the lower limit value of the excitation frequency that can be excited by the rotor of the generator motor. Because,
By controlling the output frequency of the power converter so that the slip frequency becomes the upper limit value or lower limit value of the excitation frequency that can be excited by the rotor of the AC excitation generator motor, power can be output without stopping the AC excitation generator motor. The transient stability of the system can be improved.
[0078]
The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation generator-motor. A frequency detecting means for detecting the frequency, a phase correcting means for detecting a frequency deviation between the frequency of the stator winding voltage of the AC excitation type generator motor and a predetermined frequency as a reference, and correcting a predetermined phase; and Accident detection means for detecting an accident, and when the accident detection means detects an accident in the power system, the power is based on the frequency deviation phase-corrected according to the frequency fluctuation of the stator winding voltage of the AC excitation generator motor. Since it is provided with a vibration suppression means that suppresses the fluctuation of the electric power system by controlling the effective power or rotation speed or slip frequency of the AC excitation type generator motor via the converter,
By controlling the effective power or rotational speed or slip frequency of the AC excitation type generator motor based on the phase-corrected frequency deviation, the transient stability of the power system can be improved without stopping the AC excitation type generator motor. .
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a control device for an AC excitation generator-motor according to an embodiment of the present invention.
2 is a block diagram of the acceleration / deceleration suppression signal generator of FIG. 1. FIG.
FIG. 3 is a logic circuit diagram of the system fault detector of FIG. 1;
4 is a logic circuit diagram of an accident suppression control signal transmission means in FIG. 2;
FIG. 5 is a block diagram of a control device for an AC excitation generator-motor according to another embodiment of the present invention.
6 is a block diagram of the acceleration / deceleration suppression signal generator of FIG. 5. FIG.
FIG. 7 is a block diagram of a control device for an AC excitation type generator-motor according to another embodiment of the present invention.
FIG. 8 is a logic circuit diagram of the condition detector of FIG.
FIG. 9 is a block diagram of a control device for an AC excitation type generator-motor according to another embodiment of the present invention.
10 is a configuration diagram of an excitation frequency switching unit of the converter control device of FIG. 9. FIG.
11 is a logic circuit diagram of the frequency switching condition detector of FIG. 9;
FIG. 12 is a configuration diagram of a control device for an AC excitation type generator-motor according to another embodiment of the present invention.
13 is a logic circuit and configuration diagram of the acceleration / deceleration suppression signal generator of FIG. 12. FIG.
FIG. 14 is a configuration diagram of a control device for an AC excitation type generator-motor showing another embodiment of the present invention.
FIG. 15 is a configuration diagram of a control device for an AC excitation type generator-motor according to another embodiment of the present invention.
16 is a configuration diagram of the active power limiter of FIG. 15;
FIG. 17 is a block diagram of a prime mover controller showing another embodiment of the present invention.
FIG. 18 is a block diagram of a prime mover controller showing another embodiment of the present invention.
FIG. 19 is a block diagram of a prime mover controller showing another embodiment of the present invention.
[Explanation of symbols]
1 AC excitation generator motor 3 Power system 4 Power converter
6 converter control device, 7 phase and rotation speed detector, 8 voltage detector,
9 control target voltage setting device, 10 voltage deviation detector, 11 d-axis control device,
12 active power detector, 13 control target active power setting device,
14 power deviation detector, 15 q-axis control device, 30 frequency detector,
31 current detector, 32 system fault detector, 33 acceleration / deceleration suppression signal generator,
33b Accident suppression command signal transmission means,
33c Available rotational energy calculating means, 33e Control duration setting means,
33f active power calculation means, 33g suppression signal generation means, 34 condition detector,
35 control mode switching device, 40 target rotational speed change device, 41 rotational speed deviation detector,
42 frequency switching condition detector, 44 frequency change rate detector, 45 phase corrector,
46 suppression control canceller, 48 active power limiter,
50, 51, 54 prime mover controller, 106 converter controller,
106a excitation frequency switching device, 133 acceleration / deceleration suppression signal generator,
133f Controllable active power calculation means, 133e Control duration calculation means,
133g suppression signal generating means, 233 acceleration / deceleration suppression signal generator,
233c Phase correction circuit.

Claims (12)

The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation type generator-motor.
Frequency detection means for detecting the frequency of the voltage of the stator winding;
A rotational speed detecting means for detecting the rotational speed of the AC excitation generator motor;
Means for obtaining available rotational energy of the AC excitation type generator-motor based on the upper limit value and the lower limit value of the operable speed of the AC excitation type generator-motor and the rotation number;
Accident detection means for detecting an accident in the power system;
When the accident detection means detects an accident in the power system, the active power of the AC system is controlled by controlling the effective power of the AC excitation generator motor through the power converter according to the available rotational energy. Vibration suppression means for suppressing
AC excitation type generator motor control device comprising The fluctuation suppressing means increases or decreases the effective power of the AC excitation generator / motor by the possible control amount of the effective power of the AC excitation generator / motor determined from the available rotational energy and a predetermined suppression duration. 2. The control device for an AC excitation generator motor according to claim 1, wherein the control device is an AC excitation generator motor. The fluctuation suppressing means is configured to control the effective power of the AC excitation generator motor by a controllable active power value obtained based on the maximum value and minimum value of the active power operable by the AC excitation generator motor and the current effective power. The apparatus for controlling an AC excitation generator-motor according to claim 1, wherein the controller is increased or decreased. The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation type generator-motor.
Frequency detection means for detecting the frequency of the voltage of the stator winding;
A rotational speed detecting means for detecting the rotational speed of the AC excitation generator motor;
Accident detection means for detecting an accident in the power system;
When the accident detection means detects an accident in the power system, the upper limit value of the rotational speed at which the AC excitation generator motor can be operated according to the frequency fluctuation of the stator winding voltage of the AC excitation generator motor Or, the vibration suppression means for suppressing the fluctuation of the power system by controlling the rotation speed of the AC excitation type generator motor through the power converter so as to be a lower limit value,
AC excitation type generator motor control device comprising The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation type generator-motor.
Frequency detection means for detecting the frequency of the voltage of the stator winding;
A rotational speed detecting means for detecting the rotational speed of the AC excitation generator motor;
Means for determining a slip frequency from the frequency of the stator winding voltage of the AC excitation generator motor and the rotational speed;
Accident detection means for detecting an accident in the power system;
When the accident detection means detects an accident in the power system, the slip frequency is excited according to the fluctuation of the frequency of the stator winding voltage of the AC excitation generator motor. A fluctuation suppressing means for suppressing the fluctuation of the power system by controlling the output frequency of the power converter so as to be an upper limit value or a lower limit value of a possible excitation frequency;
AC excitation type generator motor control device comprising The stator winding is connected to the power system and the rotor winding is connected to a variable frequency power converter to control an AC excitation type generator-motor.
Frequency detection means for detecting the frequency of the voltage of the stator winding;
Phase correction means for detecting a frequency deviation between the frequency of the stator winding voltage of the AC excitation type generator motor and a reference predetermined frequency and correcting the predetermined phase;
Accident detection means for detecting an accident in the power system;
When the accident detecting means detects an accident in the power system, the power converter is connected via the power converter based on the frequency deviation corrected in phase according to the frequency variation of the voltage of the stator winding of the AC excitation generator motor. Swing control means for suppressing the swing of the power system by controlling the effective power or the rotational speed or the slip frequency of the AC excitation generator motor,
AC excitation type generator motor control device comprising The AC excitation according to any one of claims 1 to 6, further comprising an operation delay unit that delays the operation of the oscillation suppression unit until a predetermined condition is satisfied when the accident occurs. A control device for a generator motor. Provided with suppression operation canceling means for canceling the operation of the shaking suppression means when the deviation between the voltage frequency of the stator winding of the AC excitation type generator motor and the rated frequency of the power system becomes a predetermined value or less. The control device for an AC excitation type generator motor according to any one of claims 1 to 6, wherein the control device is an AC excitation type generator motor. 7. An output limiting means for limiting the effective power of the AC excitation type generator-motor is provided so as not to exceed the output limit of the effective power of the AC excitation-type generator motor. The control apparatus of the alternating current excitation type generator motor according to any one of the above. The AC excitation generator motor is connected to a prime mover or a rotary load, and after a predetermined time after the operation of the vibration suppression means, the frequency of the stator winding voltage of the AC excitation generator motor and the power system When the deviation from the rated frequency is greater than or equal to a predetermined value, change the output of the prime mover or the magnitude of the rotary load to change the frequency of the stator winding voltage of the AC excitation generator and the rated frequency of the power system. 7. The AC excitation generator according to claim 1, further comprising a frequency adjustment control unit that causes a deviation of the AC to be less than the predetermined value. 8. Control device. The AC excitation type generator / motor is connected to a prime mover or a rotational load, and the slip value of the AC excitation type generator / motor is an upper limit value or a lower limit value of an allowable slip value range after a predetermined time after the operation of the vibration suppression means. The slip value adjusting control means is provided to change the output of the prime mover or the rotational load so that the slip value is smaller than the upper limit value and larger than the lower limit value. The control device for an AC excitation generator motor according to any one of claims 1 to 6, wherein the control device is an AC excitation generator motor. The AC excitation type generator motor is connected to a prime mover or a rotary load, and after a predetermined time after the operation of the upper vibration suppression means, the frequency of the stator winding voltage of the AC excitation type generator motor and the power system When the deviation from the rated frequency is greater than or equal to a predetermined value and the slip value of the AC excitation type generator motor is the upper limit value or lower limit value of the allowable slip value range, the output of the prime mover or the magnitude of the rotational load is changed. The frequency adjustment control means for making the deviation between the voltage frequency of the stator winding of the AC excitation generator motor and the rated frequency of the power system less than the predetermined value, and the slip value is higher than the upper limit value. 7. The AC excitation type generator according to claim 1, further comprising slip value adjusting control means which is smaller and larger than the lower limit value. The control device of the electric motor.

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