JPH0770652A - Loop car tension control method - Google Patents

Abstract

(57) [Abstract] [Object] The present invention relates to a loop car tension control method, and in particular, an object thereof is to suppress the tension fluctuation of the loop car. [Structure] Using the speed command values for each section, the moments when the loop car starts moving and when the moving direction is reversed are detected, and the calculated tension correction value is added to the current command for the electric motor that drives the loop car. It is characterized by suppressing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loop car tension control method, and in a looper installed for the purpose of absorbing a speed difference between continuous sections in a facility for transporting a continuous body, It is an object of the present invention to suppress tension fluctuations that occur at the time of starting the movement of the loop car in the looper and at the time of reversing the moving direction due to the change of the entry side or the exit side speed.

[0002]

2. Description of the Related Art As a current command value given to an electric motor driving a loop car which moves in a short end direction and a long end direction in order to absorb a speed difference generated between consecutive sections,
Corrects the inertia of the loop car when the speed of the loop car changes,
For the purpose of suppressing the occurrence of tension fluctuation, a tension command value obtained by adding a tension correction value obtained by multiplying a single differential of the speed difference by a correction gain and a tension setting value is given.

[0003]

As a problem of the prior art, the correction method for correcting inertia of the loop car and suppressing the occurrence of tension fluctuation is not optimal, and sufficient correction is made when the loop car starts moving. However, when the signs of the speed difference between the sections are exchanged and the moving direction of the loop car is reversed, no correction is applied at all, which causes a problem of tension fluctuation.

[0004]

The present invention advantageously solves the problems of the prior art by controlling a loop car in a looper installed to absorb the transport speed of a continuum between two sections. The device is characterized in that the speed command value of each section is used to detect the start of movement of the loop car and the moment of reversal of the moving direction, and the calculated tension correction is added to the tension command value of the prior art to perform tension control. This is a tension control method.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment according to the present invention.

The loop car moves in the short end direction and the long end direction in order to absorb the speed difference generated between the continuous sections.

The electric motors 1 and 2 are installed to control the position and tension of the loop car.

The continuous body 5 to be conveyed is, for example, a cold rolled thin steel plate or the like in an iron mill.

The current command 6 is a command value given to the electric motors 1 and 2.

The control system 7 controls the tension set value and the speed command value of each section with respect to the electric motor driving the loop car installed to absorb the speed difference of the transport speed of the continuum between the two sections. The tension command value obtained from the tension correction value obtained by differentiating the difference (hereinafter abbreviated as the differential speed), and the tension correction value given by detecting the moment when the loop car starts moving and reversing the moving direction from the differential speed. I am calculating.

FIG. 2 is a diagram showing the details of the present invention in the control system. In the figure, S indicates a step.

When the correction algorithm is started, the correction calculation according to the present invention is performed (S1).

When data is taken in, the exit speed VD of the looper
And the entry speed VE are fetched (S2).

In the calculation, a differential speed ΔV between VD and VE, an absolute value of the differential speed | ΔV |, a differential differential once differential ΔV ′, and an absolute differential absolute value differential ΔΔV | ′ are calculated. (S3).

In the condition judgment, | ΔV | <A and |ΔV|'>
The movement start of the loop car and the moment of reversing the movement direction are detected by the logical product of two conditions of 0 (S4).

In the correction, if the condition is satisfied, the tension correction value obtained by multiplying ΔV 'by the correction gain K is added to the tension command value (S5).

By such tension correction, it is possible to efficiently suppress the tension fluctuation generated at the moment when the loop car starts moving and the moment when the moving direction of the loop car is reversed due to the speed difference generated between the continuous sections. Body 5
It is possible to improve the stability of the conveyance of.

FIG. 3 is a diagram showing a comparison between the embodiment of the present invention and the prior art. The time [sec] on the horizontal axis indicates the time after the loop car starts moving due to the speed difference between the continuous sections. The tension [t] on the vertical axis indicates the tension at that time.

It should be noted that in the data acquisition shown in FIG.
About 300 [mpm] as D, 0 to 500 as VE
Capture about [mpm]. In condition judgment, | ΔV | <5
When the movement start point and the moment when the movement direction is reversed are detected by the logical product of the two conditions of [mpm] and | ΔV | ′> 0, the tension correction value obtained by multiplying ΔV ′ by the correction gain 2.25 is set. It is added to the tension command value.

In the present invention, the tension is 4.0 ± 0.1 [t].
Although tension control is possible with the conventional control, tension fluctuations of about 4.0 ± 0.6 [t] occur 1 to 3 seconds after the start of loop car movement, and tension control can be stabilized. Absent.

[0022]

The tension control method with tension correction according to the present invention makes it possible to efficiently control the tension fluctuation generated at the moment when the loop car moves and the moment when the loop car moving direction is reversed due to the speed difference generated between the continuous sections. Therefore, the stability of the conveyance of the continuous body 5 can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment according to the present invention.

FIG. 2 is a diagram showing details of the present invention in a control system.

FIG. 3 is a diagram showing a comparison between an example of the present invention and a conventional technique.

[Explanation of symbols]

 1 Electric Motor 1 2 Electric Motor 2 3 Loop Car 4 Loop Car 5 Continuum to be Conveyed 6 Current Command (Tension → Current Conversion) 7 Control System

Claims (1)

[Claims] 1. A loop car control device in a looper installed to absorb a transport speed difference of a continuum between two sections, using a speed command value of each section to start and move the loop car. A loop car tension control method, which detects a moment of reversal of a direction, and suppresses a tension fluctuation generated by adding a calculated tension correction value to a current command of an electric motor driving the loop car.