JPS6314598B2 - - Google Patents
Info
- Publication number
- JPS6314598B2 JPS6314598B2 JP55140304A JP14030480A JPS6314598B2 JP S6314598 B2 JPS6314598 B2 JP S6314598B2 JP 55140304 A JP55140304 A JP 55140304A JP 14030480 A JP14030480 A JP 14030480A JP S6314598 B2 JPS6314598 B2 JP S6314598B2
- Authority
- JP
- Japan
- Prior art keywords
- current
- rolling
- motor
- acceleration
- speed
- 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
Links
- 238000005096 rolling process Methods 0.000 claims description 70
- 230000001133 acceleration Effects 0.000 claims description 23
- 238000001514 detection method Methods 0.000 claims description 2
- 239000000284 extract Substances 0.000 claims 1
- 239000000463 material Substances 0.000 description 14
- 229910000831 Steel Inorganic materials 0.000 description 11
- 239000010959 steel Substances 0.000 description 11
- 238000010586 diagram Methods 0.000 description 5
- 238000000034 method Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/48—Tension control; Compression control
- B21B37/52—Tension control; Compression control by drive motor control
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Control Of Metal Rolling (AREA)
- Control Of Multiple Motors (AREA)
Description
【発明の詳細な説明】
本発明は、鋼材を複数台の圧延機で圧延するタ
ンデム圧延機の速度制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speed control device for a tandem rolling mill that rolls steel materials using a plurality of rolling mills.
従来のこの種の速度制御装置を第１図により説
明する。 A conventional speed control device of this type will be explained with reference to FIG.
鋼材１は第１圧延機の圧延ロール２ａ，第２圧
延機の圧延ロール２ｂにより圧延される。 The steel material 1 is rolled by a rolling roll 2a of a first rolling mill and a rolling roll 2b of a second rolling mill.
第１圧延機の圧延ロール２ａの速度は速度設定
器６により与えられ、速度制御装置５ａは電力変
換器４ａの出力電圧を制御し、第１圧延機の圧延
ロール２ａの速度が速度設定器６の設定と等しく
なるように、電動機３ａの速度を制御する。 The speed of the rolling roll 2a of the first rolling mill is given by the speed setting device 6, the speed control device 5a controls the output voltage of the power converter 4a, and the speed of the rolling roll 2a of the first rolling mill is given by the speed setting device 6. The speed of the electric motor 3a is controlled so that it is equal to the setting of .
一方、第１圧延機の電動機３ａに比べ、第２圧
延機の電動機３ｂの電動機容量が小さいため、第
２圧延機の圧延ロール２ｂの速度設定は第１圧延
機の電動機３ａの速度を回転計発電機７により検
出し、これに掛算器１０にてロール径補正８を乗
じ、掛算器１１にてドラフト９を乗じることによ
り与えられる。 On the other hand, since the motor capacity of the electric motor 3b of the second rolling mill is smaller than that of the electric motor 3a of the first rolling mill, the speed setting of the rolling roll 2b of the second rolling mill is based on the speed of the electric motor 3a of the first rolling mill. It is detected by the generator 7, multiplied by the roll diameter correction 8 in the multiplier 10, and multiplied by the draft 9 in the multiplier 11.
第２圧延機の圧延ロール２ｂはこの与えられた
速度設定に対し、第１圧延機の圧延ロール２ａと
同様に速度制御装置５ｂ、電力変換器４ｂ、電動
機３ｂにより等しくなるように制御される。 The rolling rolls 2b of the second rolling mill are controlled to be equal to the given speed setting by the speed control device 5b, the power converter 4b, and the electric motor 3b, similarly to the rolling rolls 2a of the first rolling mill.
このダンデム圧延機にて圧延される鋼材１に張
力変動を生じることなく、安定に圧延するには、
各圧延機よりも鋼材出側体積速度が常に一定でな
ければならない。 In order to stably roll the steel material 1 to be rolled by this tandem rolling mill without causing tension fluctuation,
The volume velocity of the steel material exiting from each rolling mill must always be constant.
例えば、材料温度の変化、材料寸法の変動、圧
延機のロールギヤツプ及び速度設定を変化させた
場合等により、圧延ロール２ａ，２ｂの速度比が
乱れた時に、圧延ロール２ａ，２ｂ間の鋼材１に
張力変動を生じる。 For example, when the speed ratio of the rolling rolls 2a and 2b is disturbed due to a change in material temperature, a variation in material dimensions, a change in the roll gap and speed setting of the rolling mill, etc., the steel material 1 between the rolling rolls 2a and 2b is Causes tension fluctuations.
かかる場合、第１圧延機の電動機３ａは第２圧
延機の電動機３ｂに比較し、一般的には電動機容
量が大きいため、張力変動による影響は小さく、
電動機容量の小さい第２圧延機の電動機３ｂに現
われ、電動機電流の変動を生じる。 In such a case, the electric motor 3a of the first rolling mill generally has a larger electric motor capacity than the electric motor 3b of the second rolling mill, so the influence of tension fluctuations is small.
This appears in the motor 3b of the second rolling mill, which has a small motor capacity, and causes fluctuations in the motor current.
仮りに、第２圧延機の電動機３ｂに対し、後方
張力が生じたとする。 Assume that backward tension is generated in the electric motor 3b of the second rolling mill.
当然、第２圧延機の電動機３ｂの負荷が増した
ことになるが、電動機３ｂはそれにもかかわら
ず、第１圧延機の電動機３ａの回転計発電機７よ
り与えられた速度設定にて速度を制御されるた
め、電動機電流は増加し、最悪時は過電流にな
り、第２圧延機の速度制御装置５ｂは制御不能と
なり圧延不可となる。 Naturally, the load on the electric motor 3b of the second rolling mill has increased, but the electric motor 3b nevertheless maintains the speed at the speed setting given by the tachometer generator 7 of the electric motor 3a of the first rolling mill. Since the motor current is controlled, the motor current increases, and in the worst case, an overcurrent occurs, and the speed control device 5b of the second rolling mill becomes uncontrollable, making rolling impossible.
また、過電流にならないまでも張力が生じた状
態の速度比を維持することになる。 Further, even if no overcurrent occurs, the speed ratio under tension is maintained.
従つて、かゝる事態を防ぐために一般的には張
力変動を間接的であるが、電流検出器１２により
第２圧延機の電動機３ｂの電流を検出し、これを
速度設定との加算器１４に帰還し、速度制御装置
５ｂに垂下特性を持たせ、電動機速度を下げるこ
とにより張力変動を緩和させている。 Therefore, in order to prevent such a situation, the tension fluctuation is generally detected indirectly, but the current of the electric motor 3b of the second rolling mill is detected by the current detector 12, and this is added to the speed setting in the adder 14. The speed control device 5b is given a drooping characteristic, and the tension fluctuation is alleviated by lowering the motor speed.
なお、電流検出器１２で検出する電流には電動
機の加減速に必要な加減速電流と張力を生じる圧
延電流が含まれ、鋼材１がない状態では加減速電
流のみとなる。 Note that the current detected by the current detector 12 includes an acceleration/deceleration current necessary for acceleration/deceleration of the motor and a rolling current that generates tension, and in a state where the steel material 1 is not present, only the acceleration/deceleration current is included.
しかしながら、鋼材が多少の張力変動を生じて
も支障のないスラブ材のような場合にも、常に速
度制御装置５ｂに垂下特性を持たせているため、
電動機が有している電動機容量を充分に活用出来
なかつたり、予め速度設定を上げて通板性を良く
する方法をとる必要が生じる。 However, since the speed control device 5b always has a drooping characteristic, even when the steel material is a slab material that does not have any problem even if some tension fluctuation occurs,
It may not be possible to fully utilize the capacity of the motor, or it may be necessary to increase the speed setting in advance to improve threading performance.
タンデム圧延機の駆動用電動機の電動機容量が
ほぼ等しい場合、張力変動の影響が各電動機に現
われ、円滑な圧延ができない。 If the motor capacities of the drive motors of the tandem rolling mill are approximately equal, each motor will be affected by tension fluctuations and smooth rolling will not be possible.
ここにおいて、本発明は、それらの欠点を解消
するとともに、速度制御装置が制御不能となるこ
となく、円滑に圧延することが可能なタンデム圧
延機の速度制御装置を提供することを目的とす
る。 SUMMARY OF THE INVENTION An object of the present invention is to provide a speed control device for a tandem rolling mill that eliminates these drawbacks and allows smooth rolling without the speed control device becoming uncontrollable.
以下、本発明を第２図、第３図を参照して説明
する。 The present invention will be explained below with reference to FIGS. 2 and 3.
第２図は、本発明の一実施例のブロツク図であ
る。 FIG. 2 is a block diagram of one embodiment of the present invention.
第３図は、その垂下特性回路の入力特性を示す
図である。 FIG. 3 is a diagram showing the input characteristics of the droop characteristic circuit.
図面において同一符号は、同一もしくは相当部
分を表わす。 In the drawings, the same reference numerals represent the same or corresponding parts.
一般に、同容量の圧延機がタンデムに構成され
る場合、全圧延ライン速度を速度設定器１７によ
り設定し、各圧延機の圧延ロール２ａ，２ｂの速
度は圧延ロールのロールギヤツプ、ロール径等を
考慮し、各圧延ロール間の速度が調和するよう、
各圧延機の速度調整器１８ａ，１８ｂにより設定
する。 Generally, when rolling mills of the same capacity are configured in tandem, the total rolling line speed is set by the speed setting device 17, and the speed of the rolling rolls 2a and 2b of each rolling mill is determined by taking into consideration the roll gap, roll diameter, etc. of the rolling rolls. Then, so that the speed between each rolling roll is harmonized,
It is set by speed regulators 18a and 18b of each rolling mill.
従つて、各圧延機の圧延ロール速度設定は、速
度設定器１７と各速度調整器１８ａ，１８ｂの掛
算された値にて与えられる。 Therefore, the rolling roll speed setting of each rolling mill is given by the value multiplied by the speed setting device 17 and each speed regulator 18a, 18b.
各圧延ロール２ａ，２ｂの速度はこの与えられ
た各速度設定に対し、速度制御装置５ａ，５ｂ、
電力変換器４ａ，４ｂ、電動機３ａ，３ｂにより
等しくなるよう制御される。 The speed of each rolling roll 2a, 2b is determined by a speed control device 5a, 5b,
They are controlled to be equal by power converters 4a, 4b and electric motors 3a, 3b.
一方、各圧延機の電動機３ａ，３ｂの電動機電
流は検出器１２ａ，１２ｂにより検出し、電動機
電流より電動機３ａ，３ｂの加減速に必要な加減
速電流分を除去する加減速電流除去回路１３ａ，
１３ｂを介し、張力を生じている圧延電流のみを
垂下特性回路１５ａ，１５ｂに与える。 On the other hand, the motor currents of the motors 3a, 3b of each rolling mill are detected by detectors 12a, 12b, and an acceleration/deceleration current removal circuit 13a, which removes the acceleration/deceleration current necessary for acceleration/deceleration of the motors 3a, 3b from the motor current;
Only the rolling current that causes tension is applied to the droop characteristic circuits 15a and 15b via line 13b.
ここで、加減速電流の除去方法について付言す
る。 Here, an additional comment will be made regarding the method for removing acceleration/deceleration current.
電動機２ａ，２ｂの電機子電流は一般に(1)式で
表わされる。 The armature current of the electric motors 2a, 2b is generally expressed by equation (1).
IM＝IR＋Ia ……(1)
IR：圧延電流
Ia：加減速電流
負荷に対応した圧延電流IRのみを取り出したい
場合は加減速電流Iaを除去すれば良い。 I M = I R + I a ... (1) I R : Rolling current I a : Acceleration/deceleration current If you want to extract only the rolling current I R corresponding to the load, you can remove the acceleration/deceleration current I a .
そこで加減電流Iaを求める。 Therefore, find the adjustment current Ia .
加減速トルクGaは(2)式となる。 The acceleration/deceleration torque G a is expressed by equation (2).
Ga＝2π／60・GD2／４・dN／dt（Ｎ−ｍ） ……(2)
GD2／４：慣性モーメント（Kg−m2）
Ｎ：回転数（rpm）
ｔ：時間（SEC）
即ち、加減速トルクの大きさを決定する要素は
慣性モーメント（GD2／４）と加減速（dN／dt）であ
る。 G a =2π/60・GD 2 /4・dN/dt (N-m) ...(2) GD 2 /4: Moment of inertia (Kg-m 2 ) N: Number of rotations (rpm) t: Time (SEC ) That is, the factors that determine the magnitude of acceleration/deceleration torque are moment of inertia (GD 2 /4) and acceleration/deceleration (dN/dt).
次に加減速電流は(3)式で与えられる。 Next, the acceleration/deceleration current is given by equation (3).
Ia＝Ga／Φ ……(3)
Φ＝トルク係数（Ｎ−ｍ／Ａ）
従つて電機子電流IMから(3)式で求めた加減速電
流Iaを差し引くことに依り、圧延電流IRが得られ
る。 I a = Ga/Φ ...(3) Φ = Torque coefficient (N-m/A) Therefore, by subtracting the acceleration/deceleration current I a obtained by equation (3) from the armature current I M , the rolling current IR is obtained.
そこで、加減速電流除去回路１３ａ，１３ｂに
おいては、(2)，(3)式から加減速電流は電動機速度
dN／dtの関数（他の因子は全て常数である）で
あるから、予め電動機速度に対応する加減速電流
Iaを導出し、これを設定しておき、電動機２ａ，
２ｂの速度を導入して、その電動機速度の電機子
電流Iaを電動機電流IMから減算するようにしてあ
る。 Therefore, in the acceleration/deceleration current removal circuits 13a and 13b, the acceleration/deceleration current is determined by the motor speed from equations (2) and (3).
Since it is a function of dN/dt (all other factors are constants), the acceleration/deceleration current corresponding to the motor speed can be calculated in advance.
Deriving I a and setting it, the motor 2a,
2b is introduced, and the armature current I a at that motor speed is subtracted from the motor current I M.
垂下特性回路１５ａ，１５ｂは、電動機３ａ，
３ｂの容量比、圧延される鋼材、圧延ロールのロ
ールギヤツプ、速度に応じて任意に設定ができる
不感帯設定器１６ａ，１６ｂにより、検出圧延電
流に対し、第３図のように不感帯が設けられてお
り、不感帯を越える圧延電流が入力された場合に
出力する。 The drooping characteristic circuits 15a, 15b are connected to the electric motors 3a,
A dead zone is provided for the detected rolling current as shown in FIG. 3 by dead zone setting devices 16a and 16b that can be set arbitrarily according to the capacity ratio of 3b, the steel material to be rolled, the roll gap of the rolling rolls, and the speed. , is output when a rolling current exceeding the dead zone is input.
垂下特性回路５ａ，１５ｂの出力動作は接点１
９ａ，１９ｂを閉じることにより開始指令が与え
られ、出力動作を開始する。 The output operation of the droop characteristic circuits 5a and 15b is at contact 1.
A start command is given by closing 9a and 19b, and the output operation is started.
接点１９ａ，１９ｂは図には示していないが、
各圧延ロール２ａ，２ｂに鋼材１が噛込み後、一
定時間を経過したことを検出回路より閉指令が与
えられる。 Although the contacts 19a and 19b are not shown in the figure,
After the steel material 1 is bitten into each rolling roll 2a, 2b, a closing command is given from a detection circuit when a certain period of time has elapsed.
これにより許容される範囲内の張力変動に対し
ては、電動機容量を充分に活用し、ある一定値以
上の張力変動つまり不感帯を越える圧延電流分の
みを垂下特性回路１５ａ，１５ｂを介し、加算器
１４ａ，１４ｂに帰還し、速度制御装置５ａ，５
ｂに垂下特性を持たせ、電動機速度を下げ、電動
機３ａ，３ｂは互いに張力変動を緩和し合い、か
つ電動機電流が過電流になることを防止する。 As a result, for tension fluctuations within an allowable range, the motor capacity is fully utilized, and only the tension fluctuations exceeding a certain value, that is, the rolling current exceeding the dead zone, are transmitted to the adder through the droop characteristic circuits 15a and 15b. 14a, 14b, speed control devices 5a, 5
b is given a drooping characteristic to lower the motor speed, the motors 3a and 3b mutually relieve tension fluctuations, and prevent the motor current from becoming an overcurrent.
それと共に、各圧延ロール２ａ，２ｂに噛込後
一定時間経過後に垂下特性回路を動作させ、噛込
時に増加する圧延電流分による垂下特性を持たせ
ないため、各圧延ロール２ａ，２ｂに鋼材が噛込
むさいの通板性も良くなり、しかも通常圧延時も
垂下特性が必要なときのみに動作することにな
り、予め速度設定を上げて通板性を保とうとする
必要もなくなる。 At the same time, the drooping characteristic circuit is activated after a certain period of time has passed after the steel material is bitten in each rolling roll 2a, 2b. The threadability during biting is also improved, and even during normal rolling, it operates only when drooping characteristics are required, eliminating the need to increase the speed setting in advance to maintain threadability.
かくしてこれまでの説明から明らかなように、
本発明のタンデム圧延機の速度制御装置によれ
ば、電動機容量を充分に活用した円滑な圧延が可
能となる。 Thus, as is clear from the explanation so far,
According to the speed control device for a tandem rolling mill of the present invention, smooth rolling can be performed by fully utilizing the electric motor capacity.
第１図は従来装置の構成図、第２図は本発明の
一実施例の構成を示すブロツク線図、第３図はそ
の垂下特性回路の入出力を示す図である。
１……鋼材、２ａ，２ｂ……圧延ロール、３
ａ，３ｂ……電動機、４ａ，４ｂ……電力変換
器、５ａ，５ｂ……速度制御装置、６……速度設
定器、７……回転計発電機、８……ロール径補正
設定回路、９……ドリフト設定回路、１０，１１
……掛算器、１２，１２ａ，１２ｂ……電流検出
器、１３ａ，１３ｂ……加減速電流除去回路、１
４，１４ａ，１４ｂ……加算器、１５ａ，１５ｂ
……垂下特性回路、１６ａ，１６ｂ……垂下特性
不感帯設定器、１７……速度設定器、１８ａ，１
８ｂ……速度調整器、１９ａ，１９ｂ……接点。
FIG. 1 is a block diagram showing the configuration of a conventional device, FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is a diagram showing the input and output of the droop characteristic circuit. 1... Steel material, 2a, 2b... Roll roll, 3
a, 3b...Electric motor, 4a, 4b...Power converter, 5a, 5b...Speed control device, 6...Speed setting device, 7...Tachometer generator, 8...Roll diameter correction setting circuit, 9 ...Drift setting circuit, 10, 11
... Multiplier, 12, 12a, 12b ... Current detector, 13a, 13b ... Acceleration/deceleration current removal circuit, 1
4, 14a, 14b...Adder, 15a, 15b
... Drooping characteristic circuit, 16a, 16b... Drooping characteristic dead band setter, 17... Speed setting device, 18a, 1
8b...speed regulator, 19a, 19b...contact.
Claims (1)
圧延機が複数台よりなるタンデム圧延機の速度制
御装置において、 前記各圧延機には各々速度制御装置電圧を可変
することが可能な電力変換器と、 この電力変換器の出力電圧にて圧延機速度を変
える電動機と、 この電動機の加減速に必要な加減速電流と張力
を生じる圧延電流が含まれる電動機電流を検出す
る電流検出器と、 前記電動機電流より予め設定してある電動機速
度に対応する加速度電流を除去し圧延電流のみを
取り出す加減速電流除去回路と、 垂下特性を与える垂下特性回路と、この垂下特
性回路に不感帯を任意に設定する垂下特性不感帯
設定機と、 前記垂下特性回路を動作させるタイミングを与
える開始指令手段と を具備し、 電動機電流を前記電流検出器により検出し、加
減速電流除去回路を介し圧延電流を垂下特性回路
に与え、垂下特性開始指令により、電動機電流に
対する設定値を超過する電流時にのみ、速度制御
装置に垂下特性を持たせる ことを特徴とするタンデム圧延機の速度制御装
置。[Scope of Claims] 1. A speed control device for a tandem rolling mill comprising a plurality of rolling mills each driven by an independent speed control device, wherein the speed control device voltage can be varied for each of the rolling mills. A power converter, a motor that changes the rolling mill speed using the output voltage of this power converter, and a current detection device that detects the motor current that includes the acceleration/deceleration current necessary for acceleration/deceleration of this motor and the rolling current that generates tension. an acceleration/deceleration current removal circuit that removes an acceleration current corresponding to a preset motor speed from the motor current and extracts only the rolling current; a drooping characteristic circuit that provides a drooping characteristic; and a dead zone in the drooping characteristic circuit. It is equipped with a droop characteristic dead band setting device that can be arbitrarily set, and a start command means that gives a timing to operate the droop characteristic circuit, and the motor current is detected by the current detector, and the rolling current is detected through the acceleration/deceleration current removal circuit. A speed control device for a tandem rolling mill, characterized in that a droop characteristic start command given to a droop characteristic circuit causes the speed control device to have a droop characteristic only when the current exceeds a set value for a motor current.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55140304A JPS5765289A (en) | 1980-10-07 | 1980-10-07 | Controller for speed of tandem rolling mill |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP55140304A JPS5765289A (en) | 1980-10-07 | 1980-10-07 | Controller for speed of tandem rolling mill |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5765289A JPS5765289A (en) | 1982-04-20 |
| JPS6314598B2 true JPS6314598B2 (en) | 1988-03-31 |
Family
ID=15265666
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP55140304A Granted JPS5765289A (en) | 1980-10-07 | 1980-10-07 | Controller for speed of tandem rolling mill |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5765289A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5910184A (en) * | 1982-07-05 | 1984-01-19 | Toshiba Corp | Control device for motor |
| JPS60183988A (en) * | 1984-03-01 | 1985-09-19 | Toshiba Corp | Controller for motor |
-
1980
- 1980-10-07 JP JP55140304A patent/JPS5765289A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5765289A (en) | 1982-04-20 |
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