JPH0815607B2 - Plate thickness control method for steel strip rolling mill - Google Patents
Plate thickness control method for steel strip rolling millInfo
- Publication number
- JPH0815607B2 JPH0815607B2 JP63316771A JP31677188A JPH0815607B2 JP H0815607 B2 JPH0815607 B2 JP H0815607B2 JP 63316771 A JP63316771 A JP 63316771A JP 31677188 A JP31677188 A JP 31677188A JP H0815607 B2 JPH0815607 B2 JP H0815607B2
- Authority
- JP
- Japan
- Prior art keywords
- rolling
- control
- steel strip
- thickness
- strip
- 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
Links
- 238000005096 rolling process Methods 0.000 title claims description 59
- 238000000034 method Methods 0.000 title claims description 32
- 229910000831 Steel Inorganic materials 0.000 title claims description 30
- 239000010959 steel Substances 0.000 title claims description 30
- 239000000463 material Substances 0.000 description 4
- 238000005259 measurement Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
Landscapes
- Control Of Metal Rolling (AREA)
Description
本発明は、鋼帯の圧延機における板厚制御方法に係
り、更に詳しくは、圧延機を用いた鋼帯の圧延に際し、
該鋼帯の厚さを測定する板厚計から送出される板厚偏差
信号に基づき圧下装置を操作して、前記鋼帯の厚さをフ
イードバツク制御する板厚制御方法に関する。The present invention relates to a plate thickness control method in a steel strip rolling mill, and more specifically, in rolling a steel strip using a rolling mill,
The present invention relates to a plate thickness control method for controlling the thickness of the steel strip by feedback control by operating a reduction device based on a plate thickness deviation signal sent from a plate thickness gauge for measuring the thickness of the steel strip.
従来、鋼帯の圧延機における板厚制御は、第３図に示
すような方法で行なわれていた。即ち、第３図におい
て、鋼帯10の出側に設置された板厚計12で鋼帯10の厚さ
を測定し、該板厚計12から送出される板厚偏差信号Δｈ
に基づき比例・積分制御回路14で比例・積分制御を行な
い、該制御回路14から送出される指令信号ΔＳで圧下装
置16を操作して圧延ロール18a、18bの位置を変化させ、
究極的に鋼帯10の板厚をフイードバツク制御するように
していた。 しかし、第３図のような従来例においては、圧延ロー
ル18cの直下（いわゆる中立点）から板厚計12まで一定
の距離があるため、その間の鋼帯移送時間が無駄時間と
なつていた。又、このような無駄時間があるため、上記
比例・積分制御を開始してから鋼帯10が目標の板厚にな
るまで一定の時間を要し、この時間中に圧延される鋼帯
10の板厚がオフゲージ（板厚外れ）になるという問題が
あつた。このような問題（即ち、上記無駄時間が制御系
に及ぼす悪影響）は、特に低速圧延時に顕著となつてお
り、高速圧延時と同じゲインで上記比例・積分制御を行
なうとハンチングが生じていた。 このため、低速圧延時には上記板厚制御を行なわない
ようにしたり、あるいは又、低速圧延時は高速圧延時よ
りもゲインを下げて比例・積分制御を行なうようにして
いた。しかし、低速圧延時に板厚制御を行なわないよう
にすると、その部分の板厚がオフゲージ（板厚外れ）に
なる不都合があつた。又、低速圧延時に高速圧延時より
もゲインを下げて板厚制御を行なうと、制御能力が低下
し、その結果、圧延された板厚の精度が低下する不都合
もあつた。 一方、上記問題や不都合を解決するため、第４図に示
すようなスミス補償法による制御も試みられていた（O.
J.M.Smith:A Controller to Overcome Dead Time,ISA
J.,6−2,28/33（1959）参照）。即ち、スミス補償法に
よる制御のゲインをＣ、BISRA−AGC（自動厚み制御）の
チユーニング率をα、ミル定数をＭ、圧延材（鋼帯10）
の塑性定数をＱ、圧延ロール18b、18cと板厚計12の間の
鋼帯移送時間をTL、比例制御のゲインをKP、積分制御の
ゲインをKI、比例項の一次遅れ時定数をＴ、ロードセル
20によつて検出される圧延荷重をＰ、圧延荷重設定値を
P0、圧延ロール18b、18c間のギヤツプ設定値をS0とする
とき、スミス補償法による制御の構成は第４図のように
なり、板厚計12で鋼帯10の板厚偏差Δｈが検出されてか
ら圧下装置16を指令信号ΔＳが制御するまでの遅れを予
め見込んで一定の補正を加えることによつて、リアルタ
イムな板厚制御を行なうようになつている。 然し乍ら、上記スミス補償法による制御には、次のよ
うな問題が存在していた。 即ち、第１に、スミス補償法において使用されるミル
定数Ｍは実測可能であるが、圧延材の塑性定数Ｑは、材
料によつて異なるにも拘らず圧延時に実測するのが不可
能なため、推定値を用いざるを得ない。しかし、この推
定値が塑性定数Ｑの実際の値と必ずしも一致しない。こ
のようにして、塑性定数Ｑに誤差が存在すると、それが
スミス補償法による制御の誤差を招き、前記比例・積分
制御の場合よりも板厚精度に大きな誤差を生じさせると
いう問題があつた。 第２に、第４図における圧延ロール18b、18cの直下か
ら板厚計12までの鋼帯移送時間TLは下式（１）から求め
られるが、鋼帯10の移送速度（板速）を実測しない限
り、先進率ｆを実測するのは不可能であり、推定値を用
いざるを得ない。 TL＝L/V（１＋ｆ） …（１） ここで、Ｌは圧延ロール18b、18cと板厚計12の間の距
離、Ｖは圧延ロール18b、18cの周速、ｆは先進率であ
る。 しかしながら、圧延速度が加速されたり減速されたり
することによつて鋼帯10と圧延ロール18b、18c間の摩擦
係数が変化すると、これに応じて先進率ｆが変化するた
め、その推定値が実際の値と必ずしも一致しない。この
ようにして、先進率ｆに誤差が存在すると、板厚制御に
誤差を生ずるという問題があつた。Conventionally, strip thickness control in a steel strip rolling mill has been performed by the method shown in FIG. That is, in FIG. 3, the thickness of the steel strip 10 is measured by the strip thickness gauge 12 installed on the outlet side of the steel strip 10, and the strip thickness deviation signal Δh sent from the strip thickness gauge 12 is measured.
Based on the proportional / integral control circuit 14, proportional / integral control is performed, and the commanding device ΔS sent from the control circuit 14 operates the reduction device 16 to change the positions of the rolling rolls 18a, 18b.
Ultimately, the strip thickness of the steel strip 10 was controlled by feedback. However, in the conventional example as shown in FIG. 3, since there is a certain distance from directly under the rolling roll 18c (so-called neutral point) to the plate thickness gauge 12, the steel strip transfer time during that time is wasted. Further, since there is such a dead time, it takes a certain time from the start of the proportional / integral control until the steel strip 10 reaches the target plate thickness, and the steel strip rolled during this time.
There was a problem that the plate thickness of 10 became an off gauge (out of plate thickness). Such a problem (that is, the above-described adverse effect on the dead time on the control system) is particularly noticeable during low speed rolling, and hunting occurs when the proportional / integral control is performed with the same gain as during high speed rolling. Therefore, the strip thickness control is not performed during low speed rolling, or the proportional / integral control is performed during low speed rolling with a lower gain than during high speed rolling. However, if the plate thickness control is not performed during low speed rolling, there is a disadvantage that the plate thickness at that portion becomes an off gauge (plate thickness deviation). Further, when the plate thickness is controlled by lowering the gain in the low speed rolling than in the high speed rolling, the control capability is lowered, and as a result, the precision of the rolled plate thickness is lowered. On the other hand, in order to solve the above problems and inconveniences, control by the Smith compensation method as shown in FIG. 4 has also been attempted (O.
JMSmith: A Controller to Overcome Dead Time, ISA
J., 6-2, 28/33 (1959)). That is, the gain of control by the Smith compensation method is C, the tuning rate of BISRA-AGC (automatic thickness control) is α, the mill constant is M, and the rolled material (steel strip 10)
Is Q, the steel strip transfer time between the rolling rolls 18b and 18c and the plate thickness gauge 12 is T L , the gain of proportional control is K P , the gain of integral control is K I , and the first-order lag time constant of the proportional term. T, load cell
The rolling load detected by 20 is P, and the rolling load set value is
When P 0 and the gear set value between the rolling rolls 18b and 18c are S 0 , the configuration of the control by the Smith compensation method is as shown in FIG. 4, and the thickness gauge 12 shows that the thickness deviation Δh of the steel strip 10 is The plate thickness control is performed in real time by adding a certain correction in consideration of a delay from the detection to the time when the command signal ΔS controls the reduction device 16. However, the control by the Smith compensation method has the following problems. That is, first, the mill constant M used in the Smith compensation method can be measured, but the plastic constant Q of the rolled material cannot be measured during rolling although it varies depending on the material. , I have no choice but to use the estimated value. However, this estimated value does not always match the actual value of the plasticity constant Q. In this way, if there is an error in the plasticity constant Q, it causes an error in the control by the Smith compensation method, which causes a larger error in the plate thickness accuracy than in the case of the proportional / integral control. Secondly, the steel strip transfer time T L from directly under the rolling rolls 18b, 18c to the strip thickness gauge 12 in FIG. 4 is obtained from the following equation (1). Unless the actual measurement is made, it is impossible to actually measure the advanced rate f, and the estimated value must be used. T L = L / V (1 + f) (1) where L is the distance between the rolling rolls 18b and 18c and the plate thickness gauge 12, V is the peripheral speed of the rolling rolls 18b and 18c, and f is the advance rate. . However, when the coefficient of friction between the steel strip 10 and the rolling rolls 18b and 18c changes due to acceleration or deceleration of the rolling speed, the advanced rate f changes correspondingly, and the estimated value is actually Does not always match the value of. In this way, if there is an error in the advance rate f, there is a problem that an error occurs in the plate thickness control.
本発明は、かかる従来例の問題に鑑みてなされたもの
であり、その課題は、圧延機を用いて鋼帯の圧延を行な
うに際し、全圧延速度域に亘つて良好且つ安定した板厚
制御が行なえるような板厚制御方法を提供することにあ
る。The present invention has been made in view of the problems of the conventional example, the problem is, when performing the rolling of the steel strip using a rolling mill, good and stable strip thickness control over the entire rolling speed range. It is to provide a plate thickness control method that can be performed.
本発明は、圧延機を用いた鋼帯の圧延に際し、該鋼帯
の厚さを測定する板厚計から送出される板厚偏差信号に
基づき圧下装置を操作して、前記鋼帯の厚さをフイード
バツク制御する板厚制御方法において、前記鋼帯の高速
圧延時は比例・積分制御を行ない、前記鋼帯の低速圧延
時はスミス補償法による制御を行なうことにより、前記
課題を解決したものである。The present invention, when rolling a steel strip using a rolling mill, operates a reduction device based on a strip thickness deviation signal sent from a strip thickness gauge that measures the thickness of the strip, and measures the thickness of the strip. In the plate thickness control method for controlling the feed back, in the high speed rolling of the steel strip, proportional / integral control is performed, and in the low speed rolling of the steel strip, the control by the Smith compensation method is performed to solve the above problems. is there.
本発明は、鋼帯の圧延機における板厚制御方法におい
て、鋼帯の高速圧延時は比例・積分制御を行ない、鋼帯
の低速圧延時はスミス補償法制御を行なうことにより、
全圧延速度域に亘つて良好且つ安定した板厚制御を行な
うようになつている。 即ち、無駄時間が少なく、該無駄時間が左程問題とな
らない高速圧延時は、誤差の小さい比例・積分制御を行
ない、無駄時間が多く鋼帯の板厚制御に悪影響が出やす
い低速圧延時は、スミス補償法による制御を行なうとい
うように、圧延速度に応じて制御方式を切換え、全圧延
速度域に亘つて良好且つ安定した板厚制御を行なう。The present invention, in the plate thickness control method in a steel strip rolling mill, performs proportional / integral control during high-speed rolling of the steel strip, and by performing Smith compensation method control during low-speed rolling of the steel strip,
Good and stable strip thickness control is performed over the entire rolling speed range. That is, during high-speed rolling in which the dead time is short and the dead time is less of a problem on the left, proportional / integral control with a small error is performed. The control method is switched according to the rolling speed, such as the control by the Smith compensation method, and good and stable strip thickness control is performed over the entire rolling speed range.
以下、本発明の実施例について図を用いて詳しく説明
する。 第１図は本発明の実施例を説明するための構成説明図
である。 この図において、板厚計12をセンサとして含む例えば
DDC（Direct Digital Control）のような板厚制御装置
（装置の外形は図示せず）内に、比例・積分制御回路14
とスミス補償法制御回路22が並列的に設けられると共
に、速度制御装置（ASR）24から送出されるロール周速
度信号Ｖ（例えば実績値）が基準圧延速度V0以上か否か
判定する判定回路26が設けられている。 前記判定回路26がＶ≧V0と判定すると、該判定回路26
の出力により、スイツチ回路28aがオンにされて、比例
・積分制御回路14による比例・積分制御が行なわれ、判
定回路26がＶ＜V0と判定すると、該判定回路26の出力に
より、スイツチ回路28bがオンにされて、スミス補償法
制御回路22によるスミス補償法制御が行なわれる。 ところで、上記基準圧延速度V0は、例えば、比例・積
分制御のステツプ応答が、スミス補償法による制御のス
テツプ応答の２倍以内となる点を、実測データから求め
て決定することができる。即ち、第２図は、上記基準圧
延速度V0を決定するための、冷間タンデムミルの第１ス
タンドにおいて、板厚2.8mmの材料を圧延するに際し、
目標板厚を1.80mmから1.85mmに変化させたときのステツ
プ応答時間（即ち、目標板厚に完全に到達するまでの時
間）の実測値を示すグラフである。この図において、特
性曲線Ａ、Ｂは、それぞれ比例・積分制御のステツプ応
答とスミス補償法制御のステツプ応答を示している。 これらの特性曲線Ａ、Ｂから、圧延速度Ｖが500mpm
（meter per minuite）となる付近で、特性曲線Ａ（即
ち、比例・積分制御）のステツプ応答が、特性曲線Ｂ
（即ち、スミス補償法制御）のステツプ応答の２倍以内
となることが分る。従つて、圧延速度Ｖが500mpmとなる
付近でスミス補償法制御から比例・積分制御へ制御方式
を切換えればよいことが分る。このようにして、上記基
準圧延速度V0が例えば500mpmと決定され、本発明に係る
上述の板厚制御が行なわれる。Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration explanatory view for explaining an embodiment of the present invention. In this figure, the plate gauge 12 is included as a sensor, for example
A proportional / integral control circuit 14 is installed in a plate thickness control device (the external shape of the device is not shown) such as DDC (Direct Digital Control).
And a Smith compensation method control circuit 22 are provided in parallel, and a determination circuit for determining whether or not the roll peripheral speed signal V (for example, actual value) sent from the speed control device (ASR) 24 is equal to or higher than the reference rolling speed V 0. 26 are provided. When the judging circuit 26 judges that V ≧ V 0 , the judging circuit 26
The switch circuit 28a is turned on by the output of, and the proportional / integral control circuit 14 performs proportional / integral control. When the determination circuit 26 determines V <V 0 , the output of the determination circuit 26 causes the switch circuit 28a to switch. 28b is turned on, and Smith compensation method control by the Smith compensation method control circuit 22 is performed. By the way, the reference rolling speed V 0 can be determined, for example, by determining from the actual measurement data that the step response of the proportional / integral control is within twice the step response of the control by the Smith compensation method. That is, FIG. 2 shows that when a material having a plate thickness of 2.8 mm is rolled in the first stand of a cold tandem mill for determining the reference rolling speed V 0 ,
It is a graph which shows the measured value of the step response time (namely, time until it completely reaches a target board thickness) when changing a target board thickness from 1.80 mm to 1.85 mm. In this figure, characteristic curves A and B show the step response of proportional / integral control and the step response of Smith compensation method control, respectively. From these characteristic curves A and B, the rolling speed V is 500 mpm
In the vicinity of (meter per minuite), the step response of the characteristic curve A (that is, proportional / integral control) changes to the characteristic curve B.
It can be seen that the step response of (ie, Smith compensation method control) is within twice. Therefore, it is understood that the control method may be switched from the Smith compensation method control to the proportional / integral control in the vicinity of the rolling speed V of 500 mpm. In this way, the reference rolling speed V 0 is determined to be, for example, 500 mpm, and the above-described plate thickness control according to the present invention is performed.
【発明の効果】 以上詳しく説明したような本発明によれば、鋼帯の高
速圧延時に比例・積分制御を行ない、低速圧延時にはス
ミス補償法制御を行なうような構成であるため、圧延機
を用いて鋼帯の圧延を行なうに際し全圧延速度域に亘つ
て良好且つ安定した板厚制御が行なえるようになる。 因みに、冷間タンデム圧延機の第１スタンドに本発明
を適用したところ、コイル先端とコイル尾端の低速圧延
部にオフゲージが発生するのを回避でき、全圧延速度域
に亘つてΔ13m/コイルのオフゲージ減少を達成すること
ができた。EFFECTS OF THE INVENTION According to the present invention described in detail above, the rolling mill is used because the proportional / integral control is performed during high-speed rolling of the steel strip and the Smith compensation method control is performed during low-speed rolling. When performing the rolling of the steel strip, good and stable strip thickness control can be performed over the entire rolling speed range. By the way, when the present invention is applied to the first stand of the cold tandem rolling mill, it is possible to avoid the occurrence of an off gauge in the low speed rolling portion of the coil tip and the coil tail end, and it is possible to reduce Δ13 m / coil over the entire rolling speed range. We were able to achieve off-gauge reduction.
第１図は、本発明の実施例を説明するための構成説明
図、 第２図は、本発明における基準圧延速度を決定するべ
く、比例・積分制御とスミス補償法による制御のステツ
プ応答の実測値を比較して示す線図、 第３図は、比例・積分制御による板厚制御の従来例を説
明するための構成説明図、 第４図は、スミス補償法による制御を説明するための構
成説明図である。 10…鋼帯、12…板厚計、14…比例・積分制御回路、16…
圧下装置、18a〜18d…圧延ロール、22…スミス補償法制
御回路。FIG. 1 is a configuration explanatory view for explaining an embodiment of the present invention, and FIG. 2 is an actual measurement of step response of control by proportional / integral control and Smith compensation method in order to determine a reference rolling speed in the present invention. FIG. 3 is a diagram for comparing values, FIG. 3 is a configuration explanatory view for explaining a conventional example of plate thickness control by proportional / integral control, and FIG. 4 is a configuration for explaining control by the Smith compensation method. FIG. 10 ... Steel strip, 12 ... Plate thickness gauge, 14 ... Proportional / integral control circuit, 16 ...
Reduction device, 18a to 18d ... rolling roll, 22 ... Smith compensation method control circuit.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 計測自動制御学会論文集、19［３］（昭 58−３）渡部、伊藤、ＰＰ．187−192 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Transactions of the Society of Instrument and Control Engineers, 19 [3] (Sho 58-3) Watanabe, Ito, PP. 187-192
Claims (1)
の厚さを測定する板厚計から送出される板厚偏差信号に
基づき圧下装置を操作して、前記鋼帯の厚さをフイード
バツク制御する板厚制御方法において、 前記鋼帯の高速圧延時は比例・積分制御を行ない、 前記鋼帯の低速圧延時はスミス補償法による制御を行な
うことを特徴とする鋼帯の圧延機における板厚制御方
法。1. When rolling a steel strip using a rolling mill, a rolling-down device is operated based on a strip thickness deviation signal sent from a strip thickness gauge for measuring the thickness of the strip and the thickness of the strip is measured. In a strip thickness control method for controlling the feed back by adjusting the thickness, a proportional / integral control is performed during high-speed rolling of the steel strip, and a Smith compensation method is used during low-speed rolling of the steel strip. Thickness control method for machine.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63316771A JPH0815607B2 (en) | 1988-12-15 | 1988-12-15 | Plate thickness control method for steel strip rolling mill |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63316771A JPH0815607B2 (en) | 1988-12-15 | 1988-12-15 | Plate thickness control method for steel strip rolling mill |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02165806A JPH02165806A (en) | 1990-06-26 |
| JPH0815607B2 true JPH0815607B2 (en) | 1996-02-21 |
Family
ID=18080742
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63316771A Expired - Lifetime JPH0815607B2 (en) | 1988-12-15 | 1988-12-15 | Plate thickness control method for steel strip rolling mill |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0815607B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103464469A (en) * | 2013-09-06 | 2013-12-25 | 鞍钢股份有限公司 | Edge reduction control method of cold-rolled non-oriented silicon steel |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9317928D0 (en) * | 1993-08-26 | 1993-10-13 | Davy Mckee Poole | Rolling of metal strip |
-
1988
- 1988-12-15 JP JP63316771A patent/JPH0815607B2/en not_active Expired - Lifetime
Non-Patent Citations (1)
| Title |
|---|
| 計測自動制御学会論文集、１９［３（昭５８−３）渡部、伊藤、ＰＰ．１８７−１９２ |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103464469A (en) * | 2013-09-06 | 2013-12-25 | 鞍钢股份有限公司 | Edge reduction control method of cold-rolled non-oriented silicon steel |
| CN103464469B (en) * | 2013-09-06 | 2015-11-18 | 鞍钢股份有限公司 | Edge reduction control method of cold-rolled non-oriented silicon steel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02165806A (en) | 1990-06-26 |
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