JPH1144404A - Combustion controller for boiler - Google Patents
Combustion controller for boilerInfo
- Publication number
- JPH1144404A JPH1144404A JP21564797A JP21564797A JPH1144404A JP H1144404 A JPH1144404 A JP H1144404A JP 21564797 A JP21564797 A JP 21564797A JP 21564797 A JP21564797 A JP 21564797A JP H1144404 A JPH1144404 A JP H1144404A
- Authority
- JP
- Japan
- Prior art keywords
- steam
- pressure
- combustion
- detector
- steam pressure
- 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.)
- Granted
Links
- 238000002485 combustion reaction Methods 0.000 title claims abstract description 68
- 230000002159 abnormal effect Effects 0.000 claims abstract description 33
- 229920006395 saturated elastomer Polymers 0.000 claims description 8
- 230000007423 decrease Effects 0.000 claims description 5
- 230000001747 exhibiting effect Effects 0.000 abstract 1
- 230000000630 rising effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 2
- 230000002950 deficient Effects 0.000 description 1
Landscapes
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、ボイラの蒸気を
安定して供給できるようにしたボイラの燃焼制御装置に
関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiler combustion control device capable of stably supplying steam from a boiler.
【０００２】[0002]
【従来の技術】ボイラの燃焼制御装置は、負荷側に所定
圧力の蒸気を供給するため、ボイラの蒸気圧力を検出し
て、その検出値が予め設定された設定値になるように燃
焼を制御している。従来のこの種の制御動作を、図３を
参照して説明する。2. Description of the Related Art A boiler combustion control device detects the steam pressure of a boiler to supply steam at a predetermined pressure to a load side, and controls the combustion so that the detected value becomes a preset value. doing. A conventional control operation of this type will be described with reference to FIG.
【０００３】同図に示すように、燃焼停止圧力Ｐ1及び
燃焼開始圧力Ｐ2が予め設定され、ボイラの蒸気圧力を
検出する蒸気圧力検出器からの信号に基づき、蒸気圧力
が燃焼停止圧力Ｐ1まで上昇すると燃焼を停止し、燃焼
開始圧力Ｐ2まで降下すると燃焼を開始して、蒸気圧力
が予め設定された設定値、即ち燃焼停止圧力Ｐ1と燃焼
開始圧力Ｐ2の間の圧力になるように燃焼を制御してい
る。As shown in FIG. 1 , a combustion stop pressure P 1 and a combustion start pressure P 2 are set in advance, and based on a signal from a steam pressure detector for detecting the steam pressure of the boiler, the steam pressure is reduced to the combustion stop pressure P 1. combustion and rises to 1 stops, and begins to burn and drops to the combustion start pressure P 2, a preset value is steam pressure, i.e. the pressure between the combustion stop pressure P 1 and the combustion start pressure P 2 Combustion is controlled so that it becomes.
【０００４】ここに、燃焼停止圧力Ｐ1より高い異常圧
力Ｐ3が設定されているとともに、この異常圧力Ｐ3を検
出する異常圧力検出器が蒸気圧力検出器とは別に備えら
れて、この異常圧力検出器で異常圧力Ｐ3を検出した時
に燃焼を異常停止させるようにしている。しかしなが
ら、蒸気圧力検出器の故障に対しては、何ら対策が施さ
れていなかった。Here, an abnormal pressure P 3 higher than the combustion stop pressure P 1 is set, and an abnormal pressure detector for detecting the abnormal pressure P 3 is provided separately from the steam pressure detector. When the abnormal pressure P 3 is detected by the pressure detector, the combustion is abnormally stopped. However, no measures have been taken against failure of the steam pressure detector.
【０００５】このため、蒸気圧力検出器が故障して、図
４（ａ）の符号Ａで示す低圧状態の信号を出した場合、
蒸気圧力は実際は高いのであるが低いと検出される。こ
のため、蒸気圧力が燃焼停止圧力Ｐ1に達しても燃焼停
止とはならずに上昇を続け、異常圧力検出器で蒸気圧力
が異常圧力Ｐ3に達したことを検出した時に、異常停止
されることになる。For this reason, when the steam pressure detector fails and a signal in a low pressure state indicated by reference symbol A in FIG.
The steam pressure is actually high but detected as low. For this reason, even if the steam pressure reaches the combustion stop pressure P 1 , the combustion is not stopped and continues to increase. When the abnormal pressure detector detects that the steam pressure has reached the abnormal pressure P 3 , the operation is abnormally stopped. Will be.
【０００６】一方、蒸気圧力検出器が故障して、図４
（ｂ）の符号Ｂで示す高圧状態の信号を出した場合、蒸
気圧力は実際は低いのであるが高いと検出される。この
ため、蒸気圧力が実際には燃焼開始圧力Ｐ2に達しても
燃焼開始されずに下降を続け、この結果、実質的に蒸気
の供給が停止されることになる。On the other hand, when the steam pressure detector fails, FIG.
When a signal in a high pressure state indicated by a symbol B in (b) is output, it is detected that the steam pressure is high although it is actually low. For this reason, even if the steam pressure actually reaches the combustion start pressure P 2 , the combustion continues to decrease without starting the combustion, and as a result, the supply of the steam is substantially stopped.
【０００７】[0007]
【発明が解決しようとする課題】このように、蒸気圧力
検出器は、蒸気供給のための重要な機器であり、この蒸
気圧力検出器が故障すると、上記図４（ａ）（ｂ）に示
すように、蒸気が供給できなくなって、最悪の場合に
は、蒸気を使用して生産している製品等がすべて不良と
なる場合もあった。As described above, the steam pressure detector is an important device for supplying steam. If the steam pressure detector fails, the steam pressure detector shown in FIGS. 4A and 4B is used. As described above, steam cannot be supplied, and in the worst case, all products manufactured using steam sometimes become defective.
【０００８】本発明は上記事情に鑑みて為されたもの
で、蒸気圧力検出器が故障した場合でも、安全に運転を
継続して蒸気を供給できるようにしたボイラの燃焼制御
装置を提供することを目的とする。The present invention has been made in view of the above circumstances, and provides a boiler combustion control apparatus capable of safely operating and supplying steam even when a steam pressure detector fails. With the goal.
【０００９】[0009]
【課題を解決するための手段】本発明のボイラの燃焼制
御装置は、ボイラの蒸気圧力を検知する蒸気圧力検出器
からの信号に基づいて燃焼を制御するボイラの燃焼制御
装置において、蒸気温度検出器と異常圧力検出器とを備
え、燃焼停止圧力より高く設定された異常圧力まで蒸気
圧力が上昇した時、または燃焼停止後の所定時間経過後
に蒸気圧力検出器から出力される信号が蒸気圧力の低下
を示していない時に、蒸気圧力検出器異常と判断し、蒸
気温度検出器からの信号に基づいて燃焼を制御する切換
手段を備えたことを特徴とする。SUMMARY OF THE INVENTION A boiler combustion control device according to the present invention is a boiler combustion control device for controlling combustion based on a signal from a steam pressure detector for detecting the steam pressure of the boiler. A signal output from the steam pressure detector when the steam pressure rises to an abnormal pressure set higher than the combustion stop pressure, or after a lapse of a predetermined time after the stop of the combustion. A switching means is provided for determining that the steam pressure detector is abnormal when no decrease is indicated, and controlling the combustion based on a signal from the steam temperature detector.
【００１０】これにより、蒸気圧力検出器が故障して
も、蒸気温度検出器からの蒸気温度の信号に基づき燃焼
を制御し、擬似的に蒸気圧力を制御して、蒸気を供給し
続けることができる。Thus, even if the steam pressure detector fails, the combustion can be controlled based on the steam temperature signal from the steam temperature detector, and the steam pressure can be controlled in a simulated manner to continue supplying steam. it can.
【００１１】ここに、蒸気圧力検出器異常と判断した
時、蒸気圧力の設定値を、飽和蒸気圧力−飽和蒸気温度
の関係から求められる蒸気温度の設定値に変更すること
が好ましい。これにより、蒸気圧力の設定値から自動的
に蒸気温度の設定値を得ることができる。Here, when it is determined that the steam pressure detector is abnormal, it is preferable to change the set value of the steam pressure to the set value of the steam temperature obtained from the relationship between the saturated steam pressure and the saturated steam temperature. Thus, the set value of the steam temperature can be automatically obtained from the set value of the steam pressure.
【００１２】[0012]
【発明の実施の形態】以下、本発明の実施の形態を図１
及び図２を参照して説明する。図２は、本発明が適用さ
れる蒸気ボイラの全体構成図で、ボイラ本体１には、蒸
気を発生させるために該ボイラ本体１を加熱する燃焼装
置２が備えられている。また、この内部の蒸気圧力を検
出する蒸気圧力検出器４が付設されている。FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. FIG. 2 is an overall configuration diagram of a steam boiler to which the present invention is applied. The boiler main body 1 is provided with a combustion device 2 that heats the boiler main body 1 to generate steam. Further, a steam pressure detector 4 for detecting the steam pressure in the inside is provided.
【００１３】そして、この蒸気圧力検出器４からの信号
が、図１に示すように、燃焼停止圧力Ｐ1と燃焼開始圧
力Ｐ2がそれぞれ設定された燃焼制御装置３に入力さ
れ、この蒸気圧力に基づいて燃焼装置２を燃焼と燃焼停
止状態にオン／オフ制御するように構成されている。The signal from the steam pressure detector 4 is input to a combustion control device 3 in which a combustion stop pressure P 1 and a combustion start pressure P 2 are set, as shown in FIG. Is configured to perform on / off control of the combustion device 2 in a combustion and combustion stop state based on the following.
【００１４】更に、ボイラ本体１には、ボイラの異常高
圧インターロックで蒸気圧力が異常に上昇した時にボイ
ラを運転停止にする異常圧力検出器５と、ボイラの加熱
防止インターロックで蒸気温度が異常に上昇した時にボ
イラを運転停止にする蒸気温度検出器６が備えられ、こ
れらの信号も、燃焼制御装置３に入力される。そして、
前記燃焼制御装置３には、前記燃焼停止圧力Ｐ1より高
い異常圧力Ｐ3が設定され、前記異常圧力検出器５でこ
の異常圧力Ｐ3を検出した時に、従来はボイラの運転を
停止するようになっていた。Further, the boiler body 1 includes an abnormal pressure detector 5 for stopping the operation of the boiler when the steam pressure rises abnormally due to the abnormal high pressure interlock of the boiler, and an abnormal steam temperature due to the interlock for preventing heating of the boiler. A steam temperature detector 6 is provided to stop the operation of the boiler when the temperature rises to 1. The signals are also input to the combustion control device 3. And
Wherein the combustion control device 3, the combustion stop pressure P 1 higher than the abnormal pressure P 3 is set, upon detecting the abnormal pressure P 3 in the abnormal pressure detector 5, as it is conventional for stopping the operation of the boiler Had become.
【００１５】次に、図１を参照して、前記蒸気圧力検出
器４が故障した時の制御動作を説明する。ここに、蒸気
圧力検出器４の故障は、燃焼制御装置３の信号受信回路
の故障を含む概念である。Next, a control operation when the steam pressure detector 4 fails will be described with reference to FIG. Here, the failure of the steam pressure detector 4 is a concept including a failure of the signal receiving circuit of the combustion control device 3.
【００１６】先ず、同図（ａ）に符号Ａで示すように、
蒸気圧力が燃焼開始圧力Ｐ2まで低下して燃焼を開始し
た（時間ｔ1）後、蒸気圧力検出器４が故障したとす
る。この故障で、蒸気圧力があたかも低圧の信号で出力
されるが、実際には蒸気圧力が上昇し、燃焼停止圧力Ｐ
1まで上昇しても、ボイラは燃焼を停止しない。そし
て、蒸気圧力が更に上昇して異常圧力Ｐ3まで達した
時、異常圧力検出器５でこの異常圧力Ｐ3が検出される
（時間ｔ2）。First, as shown by reference numeral A in FIG.
After steam pressure starts to burn decreases to the combustion starting pressure P 2 (time t 1), the steam pressure detector 4 has failed. With this failure, the steam pressure is output as if it were a low pressure signal, but in fact the steam pressure rises and the combustion stop pressure P
When it rises to 1 , the boiler does not stop burning. When the steam pressure has reached the abnormal pressure P 3 rises further, this abnormal pressure P 3 is detected by the abnormal pressure detector 5 (time t 2).
【００１７】この際に、異常圧力検出器５で蒸気圧力の
異常圧力Ｐ3を検出した時に、ボイラを異常停止するこ
となく、先ず蒸気圧力検出器４の異常と判断して警報を
出力する。そして蒸気圧力の設定値、即ち燃焼停止圧力
Ｐ1及び燃焼開始圧力Ｐ2等を飽和蒸気圧力−飽和蒸気温
度の関係からそれぞれの蒸気温度の設定値、即ち燃焼停
止蒸気温度及び燃焼開始蒸気温度とに変更する。At this time, when the abnormal pressure detector 5 detects the abnormal pressure P 3 of the steam pressure, the boiler is not stopped abnormally, but it is first determined that the steam pressure detector 4 is abnormal, and an alarm is output. Then, the set values of the steam pressures, that is, the combustion stop pressure P 1 and the combustion start pressure P 2, are set to the respective steam temperature set values, that is, the combustion stop steam temperature and the combustion start steam temperature from the relationship of the saturated steam pressure and the saturated steam temperature. Change to
【００１８】そして、これ以降、蒸気温度検出器６で検
出した蒸気温度に基づき、前記蒸気温度の設定値で燃焼
をオン／オフ制御することにより、擬似的に蒸気圧力を
制御するのであり、これにより蒸気を供給し続けること
ができる。Thereafter, based on the steam temperature detected by the steam temperature detector 6, on / off control of combustion is performed at the set value of the steam temperature, thereby controlling the steam pressure in a pseudo manner. Can continue to supply steam.
【００１９】一方、同図（ｂ）に示すように、蒸気圧力
が燃焼停止圧力Ｐ1まで上昇して燃焼を停止した（時間
ｔ3）後、蒸気圧力検出器４が故障したとする。この故
障で、符号Ｂに示すように蒸気圧力が実際には低下して
いるにもかかわらず、あたかも高圧の信号で出力され
る。本発明では、燃焼停止後、所定時間Ｔを経過しても
蒸気圧力検出器４の信号が低下しないと（時間ｔ4）、
上述と同様に、先ず蒸気圧力検出器４の異常と判断して
警報を出力し、それぞれの蒸気圧力の設定値を、飽和蒸
気圧力−飽和蒸気温度の関係からそれぞれの蒸気温度の
設定値に変更する。On the other hand, as shown in FIG. 2B, suppose that the steam pressure detector 4 breaks down after the steam pressure rises to the combustion stop pressure P 1 and the combustion is stopped (time t 3 ). As a result of this failure, as shown by the symbol B, the steam pressure is actually reduced but is output as a high-pressure signal. According to the present invention, if the signal of the steam pressure detector 4 does not decrease even after the lapse of the predetermined time T after the combustion is stopped (time t 4 ),
As described above, first, it is determined that the steam pressure detector 4 is abnormal, and an alarm is output, and the set value of each steam pressure is changed to the set value of each steam temperature from the relationship of saturated steam pressure-saturated steam temperature. I do.
【００２０】そして、これ以降、蒸気温度検出器６で検
出した蒸気温度に基づき、前記蒸気温度の設定値で燃焼
をオン／オフ制御して、疑似的に蒸気圧力を制御するの
であり、これにより蒸気圧力検出器の故障にもかかわら
ず、蒸気を供給し続けることができる。Thereafter, based on the steam temperature detected by the steam temperature detector 6, the on / off control of the combustion is performed at the set value of the steam temperature to control the steam pressure in a pseudo manner. Despite the failure of the steam pressure detector, the supply of steam can be continued.
【００２１】また、蒸気温度検出器６からの蒸気温度で
ボイラの燃焼を制御している時、仮に、蒸気圧力が上昇
して、異常圧力検出器５で異常圧力Ｐ3を検出した時に
は、異常圧力状態としてボイラを異常停止させる。これ
により、安全上、支障をきたすことはない。Further, when controlling the combustion in a boiler at a steam temperature from the steam temperature detector 6, if the vapor pressure rises, and when it detects an abnormal pressure P 3 in abnormal pressure detector 5 is abnormal The boiler is stopped abnormally as a pressure state. As a result, there is no problem in safety.
【００２２】なお、この実施の形態は、燃焼をオン／オ
フ制御するようにした例を示しているが、高燃焼、低燃
焼及び燃焼停止の３位置制御にも同様に適用できる。Although this embodiment shows an example in which the on / off control of combustion is performed, the present invention can be similarly applied to three-position control of high combustion, low combustion, and stop of combustion.
【００２３】以上のように、この実施の形態によれば、
異常高圧インターロック機器、加熱インターロック機器
として従来から広く使用されている異常圧力検出器５及
び蒸気温度検出器６を利用して、蒸気圧力検出器４が故
障しても、安全に蒸気圧力を制御して安定に蒸気を供給
することができる。As described above, according to this embodiment,
Even if the steam pressure detector 4 fails, the steam pressure can be safely reduced using the abnormal pressure detector 5 and the steam temperature detector 6, which have been widely used as an abnormally high pressure interlock device and a heating interlock device. The steam can be supplied stably by controlling.
【００２４】[0024]
【発明の効果】以上に説明したように、本発明によれ
ば、蒸気圧力検出器が故障しても、蒸気温度検出器から
の蒸気温度の信号に基づき燃焼を制御し、擬似的に蒸気
圧力を制御して、蒸気を供給し続けることができる。こ
れによって、蒸気の供給停止に伴う蒸気を使用して生産
している負荷側の不具合を防止することができる。As described above, according to the present invention, even if the steam pressure detector fails, the combustion is controlled based on the steam temperature signal from the steam temperature detector, and the steam pressure is simulated. Can be controlled to continue supplying steam. As a result, it is possible to prevent a problem on the load side that is producing using the steam due to the stoppage of the steam supply.
【図１】本発明の実施の形態の蒸気圧力検出器が故障し
た時の制御動作の説明に付する図。FIG. 1 is a diagram for describing a control operation when a steam pressure detector according to an embodiment of the present invention fails.
【図２】本発明が適用されるボイラの概要を示す全体構
成図。FIG. 2 is an overall configuration diagram showing an outline of a boiler to which the present invention is applied.
【図３】従来の制御動作の説明に付する図。FIG. 3 is a diagram attached to description of a conventional control operation.
【図４】同じく、蒸気圧力検出器が故障した時の制御動
作の説明に付する図FIG. 4 is a diagram attached to a description of a control operation when a steam pressure detector fails.
１ ボイラ本体 ２ 燃焼装置 ３ 燃焼制御装置 ４ 蒸気圧力検出器 ５ 異常圧力検出器 ６ 蒸気温度検出器 DESCRIPTION OF SYMBOLS 1 Boiler main body 2 Combustion device 3 Combustion control device 4 Steam pressure detector 5 Abnormal pressure detector 6 Steam temperature detector
Claims (2)
出器からの信号に基づいて燃焼を制御するボイラの燃焼
制御装置において、蒸気温度検出器と異常圧力検出器と
を備え、 燃焼停止圧力より高く設定された異常圧力まで蒸気圧力
が上昇した時、または燃焼停止後の所定時間経過後に蒸
気圧力検出器から出力される信号が蒸気圧力の低下を示
していない時に、蒸気圧力検出器異常と判断して、蒸気
温度検出器からの信号に基づいて燃焼を制御する切換手
段を備えたことを特徴とするボイラの燃焼制御装置。1. A boiler combustion control device for controlling combustion based on a signal from a steam pressure detector for detecting a steam pressure of a boiler, comprising: a steam temperature detector and an abnormal pressure detector; The steam pressure detector is determined to be abnormal when the steam pressure has increased to the abnormal pressure set to a high value or when the signal output from the steam pressure detector does not indicate a decrease in the steam pressure after a lapse of a predetermined time after the combustion is stopped. And a switching means for controlling combustion based on a signal from the steam temperature detector.
蒸気圧力の設定値を、飽和蒸気圧力−飽和蒸気温度の関
係から求められる蒸気温度の設定値に変更する手段を更
に備えたことを特徴とする請求項１記載のボイラの燃焼
制御装置。2. When it is determined that the steam pressure detector is abnormal,
2. The boiler combustion control device according to claim 1, further comprising means for changing a set value of the steam pressure to a set value of the steam temperature obtained from a relationship between the saturated steam pressure and the saturated steam temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21564797A JP3894624B2 (en) | 1997-07-25 | 1997-07-25 | Boiler combustion control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21564797A JP3894624B2 (en) | 1997-07-25 | 1997-07-25 | Boiler combustion control system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1144404A true JPH1144404A (en) | 1999-02-16 |
| JP3894624B2 JP3894624B2 (en) | 2007-03-22 |
Family
ID=16675876
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21564797A Expired - Lifetime JP3894624B2 (en) | 1997-07-25 | 1997-07-25 | Boiler combustion control system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3894624B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012057805A (en) * | 2010-09-03 | 2012-03-22 | Samson Co Ltd | Steam boiler |
| CN107525059A (en) * | 2017-09-29 | 2017-12-29 | 宁波波力维革环保设备科技有限公司 | A kind of steam boiler failure self- recoverage control method and system |
| CN113834054A (en) * | 2021-08-31 | 2021-12-24 | 中国船舶重工集团公司第七0三研究所 | Supercharged boiler blowing-out protection method |
-
1997
- 1997-07-25 JP JP21564797A patent/JP3894624B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012057805A (en) * | 2010-09-03 | 2012-03-22 | Samson Co Ltd | Steam boiler |
| CN107525059A (en) * | 2017-09-29 | 2017-12-29 | 宁波波力维革环保设备科技有限公司 | A kind of steam boiler failure self- recoverage control method and system |
| CN107525059B (en) * | 2017-09-29 | 2024-02-23 | 宁波波力维革环保设备科技有限公司 | Steam boiler fault self-recovery control method and system |
| CN113834054A (en) * | 2021-08-31 | 2021-12-24 | 中国船舶重工集团公司第七0三研究所 | Supercharged boiler blowing-out protection method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3894624B2 (en) | 2007-03-22 |
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