JPS63192507A - Controller for sheet flatness - Google Patents

Abstract

PURPOSE:To stabilize the product quality and bringing the operation to be efficient by quantitatively correcting an output from a sheet flatness pattern extraction mechanism by directional correction of an actuator and calculation based on a rule of a knowledge base. CONSTITUTION:A signal 4 detected by a sheet flatness detector 2 is sent to a sheet flatness controller 5 and a typical pattern corresponding to the output is extracted and is sent to an inference mechanism 9. A knowledge base 10 based on an empirical rule of a mill operator determines correcting direction of an actuator and a correction amount is found by an arithmetic mechanism 12 so that a controller 14 controls the actuator. The product quality is stabilized by a device having that structure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a rolling mill that rolls a plate material, and more particularly to a plate flatness control device that controls plate flatness over the entire width direction of the plate.

(Prior art) Various methods have been proposed for plate flatness control in rolling plate materials, and one of them is, for example, controlling the actuator for roll bending, leveling, etc. according to the output of a plate flatness detector. There was something to fix.

(Problems to be Solved by the Invention) The conventional plate flatness control described above is different from control that focuses on a single point in the center of the plate width, such as plate thickness control, because it is control over the entire width direction of the plate. The logic and mathematical model that determines the amount of correction in the rolling mill has become complex, and it is difficult to control it with automatic control alone, and the rolling operator has had to rely heavily on his experience.

The present invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide a plate flatness control device that takes advantage of the experience of a rolling operator.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention comprises the following configuration. That is, the plate flatness control device of the rolling mill that rolls the plate material is as follows:
A knowledge base containing rules for actuator correction patterns for several types of representative plate flatness patterns, a plate flatness pattern extraction mechanism that extracts representative plate flatness patterns from the output of a plate flatness detector, and this It is equipped with an inference mechanism that determines the direction of actuator correction based on the output of the plate flatness pattern extraction mechanism and the aforementioned knowledge-based rules, and a calculation mechanism that determines the amount of actuator correction.

(Function) First, a knowledge base is built on how the rolling operator modifies the actuator in order to control plate flatness in actual rolling. The construction method involves selecting several typical plate flatness patterns and accumulating knowledge on how the rolling operator actually corrects the actuator for each of these patterns. Based on the knowledge base constructed in this way, knowledge engineering techniques are applied to control the system as described below.

First, the above-mentioned typical plate flatness pattern is extracted from the output of a plate flatness detector installed on the downstream side of a rolling mill that rolls a plate material (a specific extraction method will be described later). Next, with respect to this extracted plate flatness pattern, the correction direction of the actuator is determined by an inference mechanism based on the above-mentioned knowledge base.

The amount of correction of the actuator is determined according to the intensity of the extracted plate flatness pattern included in the current output of the plate flatness detector.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

The drawing is a block diagram showing the configuration of an embodiment of the present invention. In the figure, a plate flatness detector 2 installed on the downstream side of a rolling mill 1 detects the plate flatness of a material to be rolled 3, and a plate flatness signal 4 thereof is sent to a plate flatness control device 5. Inside the plate flatness control device 5, an extraction mechanism 6 extracts some representative patterns included in the output of the current plate flatness detector from a collection 7 of representative plate flatness patterns prepared in advance. It is sent as a pattern signal 8 to the inference mechanism 9.

The inference mechanism 9 determines the correction direction of the actuator according to the knowledge base 1O constructed based on the empirical rules of the rolling operator, and sends the signal 11 to the next calculation mechanism 12.

The calculation mechanism 12 determines the amount of correction of the actuator. As a result of determining the actuator correction direction and correction amount in this way, a correction signal 13 based on the actuator correction amount is sent to the actuator control device 14 for roll bending, leveling, and roll shifting.

Actuators such as roll coolant are controlled.

The operation of this embodiment configured as described above will be explained in detail below.

First, the plate flatness detection value signal 4 detected by the plate flatness detector 2 at each N position Xj (j=1+2t..., N is a natural number) in the plate width direction is detected by the plate flatness 4 once by the control device 5. sent to. The amount of actuator correction is determined inside the plate flatness control device 5, and the procedure is as follows.

■ Extraction of plate flatness representative patterns First, the extraction mechanism 6 extracts and infers how many representative patterns are included in the output of the current plate flatness detector from a collection 7 of plate flatness representative patterns prepared in advance. Send to mechanism 9. The specific extraction method is to calculate the correlation coefficient r between each representative pattern and the output of the plate flatness detector, where xj: position in the plate width direction (, j=1.2...,
N) υ(XJ): Calculates plate flatness representative patterns and extracts some representative patterns having the largest correlation coefficient r.

The representative patterns U(X) are patterns A and B in the figure.
, C...... Ear wave, medium elongation.

It is sufficient to prepare any number of reference patterns such as compound elongation, two-piece elongation, etc.

■ Reasoning mechanism 9 is used to determine the direction of actuator correction
The correction direction of the actuator is determined by The inference mechanism 9 determines the correction direction of the actuator according to the knowledge base 10 constructed based on the empirical rules of the rolling operator. As for the contents of the knowledge base 10, the following may be stored as rules, for example.

Rule 1: IF “Pattern A has been extracted.

Tl(EN Increase work roll pending force.

Rule 2: IF “Pattern B has been extracted.

THII! N Decrease intermediate roll pending force.

Rule 3: IF “Pattern E has been extracted.

THEN Reduce the leveling amount (tighten the roll gap on the work side and open the roll gap on the drive side).

Rule 4: IF “THEN pattern F was extracted
Increase the leveling amount (open the work side roll gap and tighten the drive side roll gap).

Since this knowledge base is intended to utilize the experience and intuition of skilled rolling operators, the contents may be changed at any time.

(3) Determining the magnitude of actuator correction Although the inference mechanism 9 determines the direction of actuator correction, since the contents of the knowledge base 10 depend solely on the experience and intuition of the rolling operator, It is not possible to quantitatively determine the magnitude of the correction amount. Therefore, the calculation mechanism 12 determines the amount of correction of the actuator in the following manner. For example, if pattern A is extracted as a representative pattern, calculate the value of the formula R below that represents the component of pattern A included in the output of the plate flatness detector, and multiply this by gain K. (The value of K is set in advance by the operator.)C=R−K・
.... (3) is the magnitude C of the amount of correction of the work roll pending force. Even when other patterns are extracted, the magnitude C1 (i=1.2, . . . ) of the correction amount for each actuator is determined using a similar method.

(b) Modification of the actuator Since the direction of correction of the actuator and the magnitude of the correction amount C have been determined by the above-mentioned steps ① and (v), the signal 13 based on the amount of correction of the actuator is transmitted to the actuator control device 14. and each actuator is corrected.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, plate flatness control is performed using a thrust wheel mechanism that utilizes knowledge engineering techniques in accordance with a knowledge base constructed based on the experience and intuition of a rolling operator. Therefore, by building a knowledge base that utilizes the experience and intuition of skilled rolling operators, even rolling operators who are inexperienced in plate flatness control can perform stable and high-quality rolling operations.

[Brief explanation of the drawing]

The drawing is a block diagram showing the configuration of an embodiment of the present invention. 1... Rolling mill, 2... Plate flatness detector, 3...
...Rolled material, 4...Plate flatness detection value signal, 5
...Plate flatness control device, 6...Extraction mechanism, 10
...Knowledge base. 11... Actuator correction direction signal, 12...
- Calculation mechanism, 13...actuator correction amount signal, 14...
Actuator control device agent Patent attorney Nori Chika Yudo Hirofumi Mitsumata

Claims (1)

[Claims] A plate flatness control device for a rolling mill that rolls plate materials uses a knowledge base that includes rules for actuator correction patterns for several types of typical plate flatness patterns, and a representative plate flatness control device based on the output of a plate flatness detector. a plate flatness pattern extraction mechanism that extracts a plate flatness pattern, an inference mechanism that determines the direction of correction of the actuator based on the output of the plate flatness pattern extraction mechanism and the rules of the knowledge base, and a size of the correction amount of the actuator. A plate flatness control device comprising: a calculation mechanism for determining the flatness of a plate.