JPH07103810B2 - Steam valve controller - Google Patents
Steam valve controllerInfo
- Publication number
- JPH07103810B2 JPH07103810B2 JP11555986A JP11555986A JPH07103810B2 JP H07103810 B2 JPH07103810 B2 JP H07103810B2 JP 11555986 A JP11555986 A JP 11555986A JP 11555986 A JP11555986 A JP 11555986A JP H07103810 B2 JPH07103810 B2 JP H07103810B2
- Authority
- JP
- Japan
- Prior art keywords
- signal
- valve
- steam valve
- steam
- position detection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- Control Of Turbines (AREA)
Description
【発明の詳細な説明】 〔発明の目的〕 （産業上の利用分野） 本発明は、火力や原子力発電プラント等の蒸気タービン
において用いられる蒸気弁の制御装置に関する。The present invention relates to a control device for a steam valve used in a steam turbine such as a thermal power plant or a nuclear power plant.
（従来の技術） 蒸気タービンには蒸気流量を負荷に応じて制御するため
に蒸気弁が設けられている。この蒸気弁は通常、複数弁
が並設され、３弁ないしは４弁がほぼ同じ開度で制御さ
れることが多い。各弁は位置検出器によって弁実開度を
検出され、これらの位置検出信号と、開度要求信号との
信号差によって制御されている。(Prior Art) A steam valve is provided in a steam turbine to control a steam flow rate according to a load. In this steam valve, usually, a plurality of valves are arranged in parallel, and three or four valves are often controlled with substantially the same opening. The actual position of each valve is detected by a position detector, and controlled by the signal difference between these position detection signals and the opening request signal.
（発明が解決しようとする問題点） 位置検出器が、それ自体の異常や脱落等によって弁実開
度を正常に反映しない場合には、開度要求信号に対する
フィードバック信号がバランスしないため、蒸気弁は開
方向または閉方向に暴走し、正常な制御が不可能とな
る。このような場合には、タービン前圧の急変により、
プラントが停止に至るという不都合が生じる。(Problems to be Solved by the Invention) When the position detector does not normally reflect the actual valve opening due to an abnormality or dropout of the position detector, the feedback signal for the opening request signal does not balance, so the steam valve Runs uncontrollably in the opening or closing direction, making normal control impossible. In such a case, due to a sudden change in turbine front pressure,
The inconvenience that the plant will stop will occur.
（問題点を解決するための手段） 本発明の蒸気弁制御装置は蒸気弁を駆動する変化率演算
器と、この変化率演算器を制御するサーボ弁と、前記蒸
気弁を駆動する変化率演算器に連結されて前記蒸気弁の
位置検出信号を出力する位置検出器と、この位置検出器
からの位置検出信号、開度要求信号、手動閉動作信号お
よび手動開動作信号を入力し、前記サーボ弁に制御信号
を出力する蒸気弁制御装置において、前記制御装置には
蒸気弁を低速で開動作させる偏差信号を発生する信号発
生器と、蒸気弁を低速で閉動作させる偏差信号を発生す
る信号発生器と、微開または微閉信号を発生する信号発
生器と、開度要求信号および位置検出信号を入力して偏
差信号を出力する加算器とが設けられていことを特徴と
する。(Means for Solving Problems) A steam valve control device according to the present invention includes a change rate calculator that drives a steam valve, a servo valve that controls the change rate calculator, and a change rate calculator that drives the steam valve. A position detector connected to the output device to output the position detection signal of the steam valve, and the position detection signal from this position detector, the opening request signal, the manual closing operation signal and the manual opening operation signal are input, and the servo In a steam valve control device for outputting a control signal to a valve, the control device includes a signal generator for generating a deviation signal for opening the steam valve at a low speed and a signal generator for generating a deviation signal for closing the steam valve at a low speed. A generator, a signal generator that generates a slightly opened or slightly closed signal, and an adder that inputs an opening request signal and a position detection signal and outputs a deviation signal are provided.
（作用） 本発明においては、運転中の弁位置検出器のなんらかの
異常による弁開度制御不能という事態を回避し、プラン
トの停止という事態を可及的に回避することができる。(Operation) In the present invention, it is possible to avoid the situation in which the valve opening degree cannot be controlled due to some abnormality in the valve position detector during operation, and the situation in which the plant is stopped can be avoided as much as possible.
（実施例） 以下、図面を参照して本発明の実施例を説明する。Embodiments Embodiments of the present invention will be described below with reference to the drawings.
第１図は本発明による蒸気弁制御装置の一実施例を示す
もので、蒸気タービン（図示せず）への蒸気流量を制御
するために蒸気弁１が設けられている。この蒸気弁は油
圧シリンダ２によって開閉駆動される。油圧シリンダ２
は制御装置３からの信号４によって制御されるサーボ弁
５の開閉動作によって駆動される。また蒸気弁１の開度
は油圧シリンダ２に取付けられた位置検出器６によって
検出され、位置検出信号7aとして制御装置３に送られ
る。FIG. 1 shows an embodiment of a steam valve control device according to the present invention, in which a steam valve 1 is provided for controlling the flow rate of steam to a steam turbine (not shown). The steam valve is opened and closed by a hydraulic cylinder 2. Hydraulic cylinder 2
Is driven by the opening / closing operation of the servo valve 5 controlled by the signal 4 from the controller 3. Further, the opening degree of the steam valve 1 is detected by a position detector 6 attached to the hydraulic cylinder 2 and sent to the control device 3 as a position detection signal 7a.
なお、上記蒸気弁１、油圧シリンダ２、サーボ弁５、位
置検出器６は３台ずつ並設されており、制御装置３には
位置検出信号7aと共に、同時開閉動作を行う他の蒸気弁
（図示せず）の開度を示す位置検出信号7b,7cも同様に
入力し、また手動閉動作信号９および手動開動作信号10
も入力しサーボ弁５へ制御信号４を送る。The steam valve 1, the hydraulic cylinder 2, the servo valve 5, and the position detector 6 are arranged in parallel at three units, and the control device 3 receives the position detection signal 7a together with another steam valve (which opens and closes simultaneously). The position detection signals 7b and 7c indicating the opening degree (not shown) are also input in the same manner, and the manual closing operation signal 9 and the manual opening operation signal 10 are also input.
Is also input and the control signal 4 is sent to the servo valve 5.
第２図は制御装置３の詳細構造を示すものである。弁の
開度要求信号８と当該弁の位置検出信号7aは加算器11で
比較演算され、偏差信号12が出力される。この偏差信号
は接点13,14を通して増幅器15に導かれ、そこで増幅さ
れてサーボ弁５への制御信号４となる。FIG. 2 shows a detailed structure of the control device 3. The valve opening request signal 8 and the valve position detection signal 7a are compared and calculated by an adder 11, and a deviation signal 12 is output. This deviation signal is guided to the amplifier 15 through the contacts 13 and 14, and is amplified there to become the control signal 4 to the servo valve 5.
他方、中間値選択器16は位置検出信号7a,7b,7cを入力し
て比較し、その中間信号17を出力する。すなわち、例え
ば7b＜7a＜7cの条件が入力された場合には、出力信号は
7aとなる。この中間信号17は加算器18で比較演算され、
その偏差信号19が出力される。信号発生器20は偏差信号
19を入力して信号21を発する。この信号21はタイマー22
を介して接点13,23に伝達され、これらを制御する。On the other hand, the intermediate value selector 16 inputs the position detection signals 7a, 7b and 7c, compares them, and outputs the intermediate signal 17. That is, for example, when the condition of 7b <7a <7c is input, the output signal is
It becomes 7a. This intermediate signal 17 is compared and calculated by the adder 18,
The deviation signal 19 is output. Signal generator 20 is a deviation signal
Input 19 and emit signal 21. This signal 21 is a timer 22
Is transmitted to the contacts 13 and 23 via the to control them.
一方、手動開動作信号10は接点23を介して14を制御す
る。また手動閉動作信号９は接点24を制御する。On the other hand, the manual opening operation signal 10 controls 14 via the contact 23. Further, the manual closing operation signal 9 controls the contact 24.
信号発生器25は蒸気弁１を微小開閉動作させる信号26を
発生する。この信号は接点24,13,14および増幅器15を介
してサーボ弁５への制御信号４となる。The signal generator 25 generates a signal 26 that causes the steam valve 1 to perform a minute opening / closing operation. This signal becomes the control signal 4 to the servo valve 5 via the contacts 24, 13, 14 and the amplifier 15.
信号発生器27は蒸気弁１を低速で閉める信号28を発生
し、この信号は接点24,13,14および増幅器15を介してサ
ーボ弁５への制御信号４となる。また、信号発生器29は
蒸気弁１を低速で開ける信号30を発生する。この信号30
は接点14、増幅器15を介してサーボ弁５への制御信号４
となる。The signal generator 27 generates a signal 28 for closing the steam valve 1 at a low speed, which signal is the control signal 4 to the servo valve 5 via the contacts 24, 13, 14 and the amplifier 15. The signal generator 29 also generates a signal 30 for opening the steam valve 1 at a low speed. This signal 30
Is the control signal 4 to the servo valve 5 via the contact 14 and amplifier 15.
Becomes
次ぎに、上述のように構成した本発明装置の動作を説明
する。Next, the operation of the device of the present invention configured as described above will be described.
蒸気タービンの通常運転時には３台の蒸気弁１はほぼ同
じ開度にあるため、位置検出信号7a,7b,7cの中間信号17
と位置検出信号7aとの偏差信号19は微小である。この
時、信号発生器20は接点13を信号12側に保持し、かつ、
接点23を開にする信号を発している。この場合は安定状
態にあるため、タイマー22の影響は受けない。また、こ
の時、蒸気弁１は開度要求信号８によって制御されてお
り、開度要求信号８と、弁位置検出信号7aとが加算器11
で比較演算されているが、両信号８と7aはほぼバランス
しており，偏差信号12は非常に小さな値となっている。During normal operation of the steam turbine, since the three steam valves 1 have almost the same opening, the intermediate signal 17 of the position detection signals 7a, 7b, 7c
The deviation signal 19 between the position detection signal 7a and the position detection signal 7a is minute. At this time, the signal generator 20 holds the contact 13 on the signal 12 side, and
It emits a signal to open contact 23. In this case, the timer 22 is not affected by the stable state. Further, at this time, the steam valve 1 is controlled by the opening request signal 8, and the opening request signal 8 and the valve position detection signal 7a are added by the adder 11.
Although both signals 8 and 7a are almost balanced, the deviation signal 12 has a very small value.
この偏差信号12は接点13,14を経て増幅器15に入力し、
そこで増幅された後、サーボ弁５へ制御信号４として出
力されるが、偏差信号12が微小であるからサーボ弁５は
蒸気弁１を一定開度に保つよう制御する。This deviation signal 12 is input to the amplifier 15 via the contacts 13 and 14,
After being amplified there, it is output as a control signal 4 to the servo valve 5, but since the deviation signal 12 is minute, the servo valve 5 controls the steam valve 1 to maintain a constant opening.
なお、蒸気タービンが過渡状態にある時、各蒸気弁の動
きは機械差により多少バラツクことがあり、その場合に
は位置検出信号7a,7b,7cにもバラツキを生ずるが、この
時には、中間信号17と位置検出信号7aの偏差信号19が大
きくなり、規定値を一時的に越えることがある。この場
合、信号発生器20からの信号も変化するが、タイマー22
によって偏差信号19が所定の時間以上、規定値を越える
状態が続かない限り、接点13,23は切換わらない。この
様な過渡状態は正常なものであるため、この動作は妥当
である。When the steam turbine is in a transient state, the movement of each steam valve may vary slightly due to mechanical differences.In that case, the position detection signals 7a, 7b, 7c also vary, but at this time, the intermediate signal The deviation signal 19 between the position detection signal 7a and the position detection signal 17a may become large and may temporarily exceed the specified value. In this case, the signal from the signal generator 20 also changes, but the timer 22
Therefore, the contacts 13 and 23 are not switched unless the deviation signal 19 exceeds the specified value for a predetermined time or longer. This behavior is reasonable because such transients are normal.
次に位置検出器６が脱落や、故障等によって誤った位置
検出信号7aを発生させた場合には、開度要求信号８に対
して位置検出信号7aはバランスせず偏差信号12は＋また
は−の大きな偏差値となる。これによって、蒸気弁１は
弁開方向、または弁閉方向にノンコントロールの状態で
動き出すことになる。Next, when the position detector 6 generates an erroneous position detection signal 7a due to dropout or failure, the position detection signal 7a is not balanced with respect to the opening request signal 8 and the deviation signal 12 is + or-. Is a large deviation value. As a result, the steam valve 1 starts to move in the valve opening direction or the valve closing direction in a non-controlled state.
この時、位置検出信号7b,7cは正常なため、中間信号17
は前の状態とほとんど変らず、一定であるが、位置検出
信号7aが大きく異なる。このため、偏差信号19は大きな
値を示し、規定値をこえると、信号発生器20は接点13を
信号26側に切換え、かつ接点23を閉とする信号21を発生
する。At this time, since the position detection signals 7b and 7c are normal, the intermediate signal 17
Is almost unchanged from the previous state and is constant, but the position detection signal 7a is greatly different. Therefore, the deviation signal 19 shows a large value, and when it exceeds the specified value, the signal generator 20 generates the signal 21 that switches the contact 13 to the signal 26 side and closes the contact 23.
このとき、位置検出器６の故障が軽微で瞬時に復帰すれ
ば、タイマー22の働きで接点13,23は切換わらないが、
所定時間以上、復帰しない場合には接点13,23は切換え
られる。この接点13,23の切換えにより信号発生器25の
信号26が接点24,13,14、増幅器15を介してサーボ弁５に
おくられる。信号発生器25の特性は第３図に示す通りで
あり、サーボ弁５に対して、微開信号と微閉信号を交互
に短時間ずつ繰り返し入力する。従って、蒸気弁１はほ
ぼ一定の開度に抑制される。At this time, if the position detector 6 has a minor failure and is recovered instantly, the contacts 22 are not switched by the function of the timer 22, but
If the contacts are not restored for a predetermined time or longer, the contacts 13 and 23 are switched. By switching the contacts 13 and 23, the signal 26 of the signal generator 25 is sent to the servo valve 5 via the contacts 24, 13 and 14 and the amplifier 15. The characteristics of the signal generator 25 are as shown in FIG. 3, and the fine open signal and the fine close signal are alternately and repeatedly input to the servo valve 5 for a short time. Therefore, the steam valve 1 is suppressed to a substantially constant opening.
故障が軽微であって短時間に復帰するような場合は、位
置検出器６が正常に復帰すると、偏差信号19も小とな
り、信号発生器20の働きによって接点13は、信号12側に
切換えられ、全て正常状態に復帰する。In the case where the malfunction is minor and the fault is restored in a short time, when the position detector 6 returns to the normal state, the deviation signal 19 also becomes small and the contact 13 is switched to the signal 12 side by the action of the signal generator 20. , Return to normal.
故障が生じて位置検出器６の交換等が必要な場合には、
蒸気弁１を一時全閉させる必要がある。この場合には、
外部より手動閉動作信号９を入力する。この信号９によ
り接点24は信号26側から信号28側へ切換えられる。この
ため、信号発生器27の信号28が接点24,13,14を経て増幅
器15で増幅され、信号４となってサーボ弁５に送られ
る。信号発生器27の特性は第４図に示す通りであり、サ
ーボ弁５に対して微閉信号を送る。If a failure occurs and the position detector 6 needs to be replaced,
It is necessary to temporarily close the steam valve 1 completely. In this case,
Input a manual closing operation signal 9 from the outside. By this signal 9, the contact 24 is switched from the signal 26 side to the signal 28 side. Therefore, the signal 28 of the signal generator 27 is amplified by the amplifier 15 via the contacts 24, 13, 14 and becomes the signal 4, which is sent to the servo valve 5. The characteristics of the signal generator 27 are as shown in FIG. 4, and a slight closing signal is sent to the servo valve 5.
従って、蒸気弁１は、弁前圧力に大きな変動を与えない
ように極めて低速度で閉じる。このようにして蒸気弁が
全閉したら、位置検出器６等の変換やその他の点検処置
を行い、正常に復帰したことを確認した後、手動開動作
信号10を入力する。Therefore, the steam valve 1 closes at an extremely low speed so as not to make a large fluctuation in the valve front pressure. When the steam valve is completely closed in this way, conversion of the position detector 6 and the like and other inspection measures are performed, and after confirming that the steam valve has returned to normal, the manual opening operation signal 10 is input.
この信号は接点23を経由して接点14に入力し、接点14を
信号30側に切換える。その結果、信号発生器29の信号30
が接点14を経て増幅器15に入り、ここで増幅され、信号
４となってサーボ弁５に送られる。信号発生器29の特性
は第５図に示す通りであり、サーボ弁５に対して微開信
号を送る。This signal is input to the contact 14 via the contact 23, and the contact 14 is switched to the signal 30 side. As a result, the signal 30 of the signal generator 29 is
Enters the amplifier 15 via the contact 14 where it is amplified and sent as a signal 4 to the servo valve 5. The characteristics of the signal generator 29 are as shown in FIG. 5, and a slight opening signal is sent to the servo valve 5.
そのため、蒸気弁１は弁前圧力に大きな変動を与えない
ように極めて低速度で開く。この開弁動作中に中間信号
17と、その弁の位置検出信号7aとの偏差信号19が規定値
以下になると、信号発生器20は接点13を正常信号12側に
切換え、かつ接点23をOFFにする信号21をタイマー22を
介して送る。この信号21によって接点13は切替わり、ま
た接点23がOFFとなるため接点14も信号12側に切換えら
れる。この動作によって制御系は正常状態に復帰する。Therefore, the steam valve 1 opens at an extremely low speed so as not to make a large fluctuation in the valve front pressure. Intermediate signal during this valve opening operation
When the deviation signal 19 between the valve 17 and the valve position detection signal 7a falls below a specified value, the signal generator 20 switches the contact 13 to the normal signal 12 side and turns off the contact 23 by setting the signal 21 to the timer 22. Send through. The contact 13 is switched by this signal 21, and the contact 14 is switched to the signal 12 side because the contact 23 is turned off. By this operation, the control system returns to the normal state.
なお、第２図に示した実施例では、信号発生器20は同時
に開する３弁の位置検出信号7a,7b,7cの中間信号17とそ
の弁の位置検出信号7aとの偏差信号19を信号発生器20に
入力する例につき述べたが、本発明はこれに限定される
みのではなく、第６図に示すように、単にその弁の開度
要求信号８と位置検出信号7aとの偏差信号31を信号発生
器20の入力信号とするようにしてもよい。In the embodiment shown in FIG. 2, the signal generator 20 outputs the deviation signal 19 between the intermediate signal 17 of the position detection signals 7a, 7b, 7c of the three valves which are simultaneously opened and the position detection signal 7a of the valve. Although an example of inputting to the generator 20 has been described, the present invention is not limited to this, and as shown in FIG. 6, a deviation signal between the valve opening request signal 8 and the position detection signal 7a is simply used. 31 may be used as the input signal of the signal generator 20.
上述のように、本発明によれば、位置検出器に異常を生
じたとしても、抑制不能な状態とはならず、まずその開
度を保持し、しかる後に必要に応じて全閉、補修するこ
とによって運転を継続することができる。As described above, according to the present invention, even if an abnormality occurs in the position detector, it will not be in an uncontrollable state, its opening will be maintained first, and then fully closed and repaired if necessary. By doing so, the operation can be continued.
第１図は本発明の蒸気弁制御装置の実施例を示す系統
図、第２図は本発明における制御装置の実施例を示す接
続図、第３図ないし第５図は本発明装置における信号発
生器25,27,29の作動を示す特性図、第６図は本発明にお
ける制御装置の他の実施例を示す接続図である。 １…蒸気弁、２…油圧シリンダ、３…制御装置、４…制
御信号、５…サーボ弁、６…位置検出器、７…手動閉動
作信号、８…開度要求信号、９…手動閉動作信号、10…
手動開動作信号、11,18…加算器、12,19,31…偏差信
号、15…増幅器、16…中間値選択器、17…中間信号、2
0,25,27,29…信号発生器、22…タイマー。1 is a system diagram showing an embodiment of the steam valve control device of the present invention, FIG. 2 is a connection diagram showing an embodiment of the control device of the present invention, and FIGS. 3 to 5 are signal generation in the device of the present invention. FIG. 6 is a characteristic diagram showing the operation of the devices 25, 27 and 29, and FIG. 6 is a connection diagram showing another embodiment of the control device according to the present invention. 1 ... Steam valve, 2 ... Hydraulic cylinder, 3 ... Control device, 4 ... Control signal, 5 ... Servo valve, 6 ... Position detector, 7 ... Manual closing operation signal, 8 ... Opening request signal, 9 ... Manual closing operation Traffic lights, 10 ...
Manual open operation signal, 11, 18 ... Adder, 12, 19, 31 ... Deviation signal, 15 ... Amplifier, 16 ... Intermediate value selector, 17 ... Intermediate signal, 2
0,25,27,29 ... Signal generator, 22 ... Timer.
Claims (1)
化率演算器を制御するサーボ弁と、前記蒸気弁を駆動す
る変化率演算器に連結されて前記蒸気弁の位置検出信号
を出力する位置検出器と、この位置検出器からの位置検
出信号、開度要求信号、手動閉動作信号および手動開動
作信号を入力し、前記サーボ弁に制御信号を出力する蒸
気弁制御装置において、前記制御装置には蒸気弁を低速
で開動作させる偏差信号を発生する信号発生器と、蒸気
弁を低速で閉動作させる偏差信号を発生する信号発生器
と、微開または微閉信号を発生する信号発生器と、開度
要求信号および位置検出信号を入力して偏差信号を出力
する加算器とが設けられていことを特徴とする蒸気弁制
御装置。1. A rate-of-change calculator for driving a steam valve, a servo valve for controlling the rate-of-change calculator, and a rate-of-change calculator for driving the steam-valve to output a position detection signal of the steam valve. In the steam valve control device that outputs a position detector and a position detection signal from this position detector, an opening request signal, a manual closing operation signal and a manual opening operation signal, and outputs a control signal to the servo valve, The control device includes a signal generator that generates a deviation signal that causes the steam valve to open at a low speed, a signal generator that generates a deviation signal that causes the steam valve to close at a low speed, and a slightly open or slightly closed signal. A steam valve control device comprising: a signal generator; and an adder that inputs an opening request signal and a position detection signal and outputs a deviation signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11555986A JPH07103810B2 (en) | 1986-05-20 | 1986-05-20 | Steam valve controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11555986A JPH07103810B2 (en) | 1986-05-20 | 1986-05-20 | Steam valve controller |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62271909A JPS62271909A (en) | 1987-11-26 |
| JPH07103810B2 true JPH07103810B2 (en) | 1995-11-08 |
Family
ID=14665536
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11555986A Expired - Lifetime JPH07103810B2 (en) | 1986-05-20 | 1986-05-20 | Steam valve controller |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07103810B2 (en) |
-
1986
- 1986-05-20 JP JP11555986A patent/JPH07103810B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62271909A (en) | 1987-11-26 |
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