JPS5886919A - Interstand tension controlling method of continuous rolling mill - Google Patents

Abstract

PURPOSE:To execute interstand tension control which generates no offset, even if disturbance is large and a target tension value is changed, by keeping a looper angle between continuous rolling mills constant, and executing integral state feedback control. CONSTITUTION:In a rolling device provided with a looper device 3 between a front stage stand 1 and a rear stage stand 2 of a continuous rolling mill, on a looper 3, a torque controller 13 of the looper is provided, and to both stands 1, 2, mill speed controllers 11, 12 are set, respectively. Also, a control reference value, an equipment constant, etc. in the stationary state are inputted in advance to a tensin controller 21. When rolling, the interstand tension is controlled by correcting an angle deviation of the looper 3, an angular velocity deviation, an interstand tension deviation, an interstand speed deviation, a looper angle deviation integral value, and an interstand tension deviation integral value, as state vriable vectors, and a looper torque target value and a main motor speed target value, as operation vectors, along a kinematic equation of a tension controlling system, and secondary format appreciating index minimization.

Description

[Detailed Description of the Invention] Jin's invention relates to a tension control method for controlling the tension between the stands to an arbitrary target value while keeping the roux-po shield angle between the stands of a continuous rolling mill almost constant. be.

In a conventional continuous rolling mill with a tension control device that has a loop between the stands, the tension between the stands generates a predetermined torque between the stands, and the angle between the stands is controlled by the speed between the stands. Control by changing. However, this method has a so-called mutual interference system in which the tension changes as the height of the loop changes, and the height of the loop changes as the tension changes, resulting in a limit in controllability.

On the other hand, Lou! A state feedback control has been proposed in which the angular velocity change, Roux 101, tension, and plate speed difference between stands are used as state vectors, and the operating vector is Roux 101 drive torque and plate reach difference reference value between stands (4111
! (Sho 58-23309).

However, according to optimal control theory, this method constitutes a tweed wick using only proportional operation, and when there is a steady relatively large disturbance or when the target tension changes over time, the offset It is generally said that this causes a decrease in controllability.

Jin's invention was made in view of the actual situation described in E, and its purpose is to provide a method for controlling the tension between stands of a continuous rolling mill that does not cause offset by performing integral cedar-shaped reciprocating feed/paddle control. This is what I am trying to do.

The method of this invention will be explained in detail below. FIG. 1 shows the geometrical arrangement of the roux/quantity system in a general tension control system. In the figure, 1 is a front stage stand, and 2 is a rear stage stand, each of which is equipped with a speed control device. 3 is the Roux machine, which is equipped with a Roux control device (for rolling material).

Here, to simplify the explanation, the reference speed stand P (♂I knot stand) of the control is adopted for the rear stage stand 2. Therefore, the roll circumferential speed of the decorative stage stand 1 is the height and the tension between the stands. And the roots will be affected by the extra motor torque.

The Roux-Qing kinetic force li equation is linearly approximated using the reference Roux-in-direction -0° to obtain the following equation.

d 4 7-(Δ” ” ' 11 a t (Δθ) 10 m, 2
(Δθ)+Js(Δσ)+b,,(ΔTr@t)
・・・・・・・・・(1) However, 0: Luno middle angle σ: Tension between stands T. f: Drive torque Δ: Each of the operator formula (1) that indicates the deviation of the reference value layer.
The arming meter is calculated as follows.

"11"" Ding D...
Song (2)"+5""Kl('.)
Song/beat (4) b = ~ King..., used ° song (5
)K2(a)=2ρhoBOr+asθνσWateko;
+WLar'' (θ 10,) ... (7) However, g: Acceleration of gravity J nil - Inertia rate r: Arm length of Runoya Ar nil - I (Arm length of center of gravity @Nil) Off-sera from the rotating shaft and file line
Quantity t: Distance between stands 0°, 1 Offset angle of center of gravity D, coefficient of friction of front shaft ho: Material grade Bo: Material board ρ: Material vH WL nil, weight also The inter-stand tension generation formula is expressed by the following equation.

However, K4 (#) = 2 or 5 stones; -?・・・・・・・・・(9
)ΔMa,=(1+f)ΔV・・・・・・
...(2) E: Young's modulus Δma M: Material transport difference 1: # stage stand material advance rate 4 Ma: Front stage stand Y roll circumferential speed deviation Differentiate equation (8) and find linear around the reference value , and obtain the following equation.

however, On the other hand, the main Tanabata response Fi is expressed as a first-order delay.

However, Te: Main motor time constant knob r*f” stand roll same Liao steel difference indicated value and ζ
Define the following variables in ζ.

Δ'r@f sΔσ1. , the target value deviations around the reference values of ballou, angle change, and inter-stand tension.

Above (x), 01, a4, n, a*
If we combine the equations and ignore the target value O movement term, we get
We get the following equation.

Crystal x heat exchange + 1 song/song (b) However, LJ = (ΔTrsf'ΔMa1.f) That is, × indicates a shaped Ili number vector, U indicates an operation vector, and A and B indicate a coefficient matrix.

By reconsidering the integral element depending on this *#i (goods) and (to) 2 and making it a good form, we can obtain a quadratic evaluation index.However, Q: Non-negative definite matrix R: By finding U that minimizes the positive definite matrix, It performs tension control that has good responsiveness and is resistant to steady disturbances and fluctuations in target tension.

Here, Q and R constitute evaluation criteria determined by the weight IIIrR on tension control accuracy, Roux angle control accuracy, offset removability, etc.

Now, the complete set is to solve the Riccati-type mold equation and feed/
It can be minimized by finding a four-dimensional matrix K. That is,
It is optimal to feed and check the manipulated variable according to the following equation.

LJ = KX , = -0, @ In the above explanation, the bit I stand is used as the rear stage stand 2, but the same method can be applied even if it is used as the front stage stand 1.

Next, the tension control device OIIg& that performs the method of this invention is installed in the second
@ # @ Rear stand J explained with diagrams.

2 are respectively provided with mill speed control devices 1i and rx, and are also provided with a roux/tortoror control device 13. Reference numeral 21 denotes a tension control device, which has control reference values of 0° and σ0°"ref@'ma in a steady state, as well as equations (2) to (7), equations (9) to (a), and (b) to (to )
The material specifications, equipment constants, etc. necessary for the equations and equations (to) to (to) are given in advance to this tension control device 21jfC.

In addition, an inter-stand tension needle, a Roux main angle needle, and a Roux 9 self-speed needle are installed in the Roux/manual device 3, and each is provided on the t9 main motor, and the tension control device f' I is provided from the 9th speed needle to the
It is now possible to input a large K. In this case, the bit stand is the rear stand 2, and the tension control device 21 outputs the main motor speed ref of the front stand 1 and the loop/
It becomes possible to set the loop motor torque Trat of the tread device 3.

The tension control operation using the above control device and measuring instrument is performed as follows. First, σ, θ.

-0, Ma is measured, and (b), the state spectrum i is determined by the C1 equation. Next, use (1) to Sakaki equations to find the coefficient matrix and B. Find the feed/paddle r ink that minimizes the evaluation index [J] of the zero-order equation (E).

In the feed peck dyne K, each element of the state vector determines the weight to be given to the main motor speed change amount and the Roux torque change f.

Finally, the front stage stand roll #fjA luck-difference instruction value and the driving torque of the #stage stand's main motor and the Ru I? The temperature of 0 or more that is set for each motor depends on the control that is performed every certain threshold period, and can be controlled without causing an offset in response to steady disturbances and changes in the tension target value. .

FIG. 3 shows nine cases in which the method of this invention is applied and compared with the conventional method. This shows that the offset occurs in the conventional method for nine disturbances entering the run l shape, but it is possible to reduce the offset intermittently by the integral type control of the present invention.

The method of the present invention is as described above, and by performing integral state feedback control, it is possible to perform inter-stand tension control without causing offset even if the disturbance is large or the target tension value is changed.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a general tension control system for explaining the method of this invention, Fig. 2 is an explanatory diagram of a general tension control system for implementing the method of this invention, and Fig. 3 is an explanatory diagram of a general tension control system according to the method of this invention. FIG. 3 is an explanatory diagram showing the response of the control system in comparison with a conventional method. 1...Front stage stand, 2...Rear stage stand P53...
Lu Yasoupui, 11.12... Mill speed control device. 13 Roux/mother torque control device, 21... tension control device. Applicant's agent Patent attorney Takeshi Suzue Hikosai 1YI! A Figure 2 Figure 3 - 1112 condition

Claims (1)

[Claims] Equipped with a tension control method that is arranged between the stands of a continuous rolling mill and consists of a torque control device of 9 mm and a speed control device of 1 to control the tension between the stands to a target value while controlling the ζ angle to a constant value. In the continuous rolling mill inter-stand tension control method, the above-mentioned angular variation deviation, self-speed [4 difference, inter-stand tension deviation, inter-stand speed deviation, and 1-difference integral of Roux and arm angle] are used. The value and the integrated value of the tension deviation between stands are used as state variable vectors, and the torque target value and main mo-moderate target value are corrected as operation vectors according to the equation of motion of the tension control system and quadratic form evaluation index minimization. ``Opening force control method'' for a continuous rolling mill, which is characterized by controlling the tension between the meta 71 and the continuous rolling mill.