CS209071B1 - Method of loop regulation of continuous processes and connection for execution of this method - Google Patents

Abstract

A loop control for a continuous process, esp. for continuous rolling mills, is based on scanning the position of the loop at >=2 points. The readings are averaged and compared with the desired value of the loop deflection. Any discrepancy produces a correcting signal for one of the stand motors. The prefd. scanner is a TV camera. Compared with a single-point scanning by revolving mirrors, this eliminates the fluctuations of the reading independent of the relative loop elongation.

Description

(54) A method for loop control of continuous processes and wiring for performing this method

The invention relates to a process for the slip control of continuous processes, for example rolling mills, and to an arrangement for carrying out the process.

The state of the art is characterized by sensing the position of the loop at one point, usually using a rotating mirror system. The thus obtained actual loop position information is fed to a loop deviation controller in which it is compared to an optional loop position setpoint. The output of this controller then controls the drive of the previous or subsequent mill to minimize the deviation between the setpoint and the actual loop value. ₅

The disadvantage of this system is the fluctuation of the measured value of the loop deviation independently of the relative elongation of the loop, this effect is mainly caused by oscillations of the strings or scales. This variation is particularly dangerous for low loops used in heavier profiles, where the speed of the regulator's intervention must be high and the oscillation of the actual value of the loop position leads to rapid changes in drive torque and thus premature wear of the gearboxes.

The invention overcomes these drawbacks, in which the position of the loop is sensed at at least two points and the relative elongation of the loop is approximated by a functional value, for example, the mean of the loop position data. the speed of at least one of the actuators before or after the loop is controlled so that the difference between the setpoint and the actual value of the loop position is minimized.

Obviously, when measuring a large number of points spaced along the entire loop, the resulting mean value approximating the relative elongation of the loop, except for the second order error, is independent of the oscillation of the struts, as well as the variation caused by scale at one measurement point averaged.

In the accompanying drawing, an example of the connection of a continuous process loop control system for carrying out the method according to the invention is shown. The loop deviation sensor 1 connected by its inputs to the measuring points 1 ', 2' to n is connected via its output via the function generator block 2 to the first input 30 of the loop deviation controller 3, whose second input 31 is connected to the loop deviation setpoint block output 4 The output of the loop deviation regulator 3 is connected both to the first stool drive 5 before the loop and:. to the second drive 6 stools behind the loop. The loop deviation sensor 1 is formed, for example, by a television camera. The function generator block 2 is formed, for example, by an average value circuit, to which a quadrature block can be connected.

The position of the loop is scanned at at least two points, and - the relative elongation of the loop is approximated by the functional value, - for example, the mean, from the loop position data, is compared. The speed of at least one of the actuators before or after the loop is controlled so that the difference between the setpoint and the actual value * of the loop position is minimized.

The use of the current loop offset sensors for multi-point scanning is apparently virtually impossible for economic reasons, on the other hand, multi-point scanning with subsequent formation; The mean values or other functional values in the functional generator are nowadays real via some CCTV systems. In most cases, the function generator produces the mean value of the measured deviations. For possible linearization - relations between the relative elongation of the loop and the output it is possible to add a linearization element, for example a quadrator.

Claims (3)

SUBJECT t ** · • 1. Method of loop control of continuous processes,. For example, rolling mill, characterized in that the position of the loop is sensed at at least two points and the relative elongation of the loop is approximated by a functional value, for example mean, of the loop position data, actuators upstream or downstream of the loop so as to minimize the difference between the setpoint and the actual value of the loop position. Wiring for carrying out the method according to claim 1, comprising loop displacement sensors, a functional 'generator', a 'deviation-regulator' block and drives, characterized in that the output of the loop deflection sensor (1) is over a functional-generator block (2) connected to the first input (30) of the controller OF THE INVENTION _{: the} deviations of the loop (3) whose second input (31) is I 'is connected to the output of the setpoint block of deviation of the loop (4) and whose output is connected on the one hand I to the first drive (5) of the stool before the loop Ί i 'and to the second drive (6). . stool behind the 'loop. 3. Circuit arrangement according to point '2, characterized in that the sensor (1) is formed by a loop deviation television kamerou.ί ¹ 4. The system according to claim 2, wherein' i of the function generator block '. (2) is formed by a circuit ^. tvorbu to create a mean value. < I 5. Wiring. according to claim 4, characterized in that ι is connected to the mean value circuit, an I block of the quadrator is connected.