JPH05263152A - Speed controller for continuous heat treatment line - Google Patents

Abstract

PURPOSE:To provide a speed controller in a continuous heat treatment line by which a looper residual quantity can automatically and suitably be controlled. CONSTITUTION:The speed in the line is controlled by taking into account the upper and the lower limit velocities VMAX, VMIN in driving based on a fuzzy control output VF being a deviation between the min. value V12 in the inlet side and the outlet side looper detected values I1, I2 obtd. from a fuzzy arithmetic operation based on the looper residual quantities and the line speed in the inlet side and outlet side loopers 2, 4 and a velocity setting value correcting quantity DELTAVS obtd. from the fuzzy arithmetic operation based on a heating zone outlet strip temp. detected value TS indicating the strip temp. at the outlet in the heating zone, the aimed strip temp. TSSET and the line speed in a center treatment section 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed control device for a continuous heat treatment line, and is useful when applied to a continuous heat treatment furnace line such as a continuous annealing line, a continuous plating line or a stainless steel plate annealing pickling line.

[0002]

2. Description of the Related Art Normally, a continuous heat treatment line for strips (steel plates) S is largely divided into an inlet side section 1, an inlet side looper 2, a central processing section 3, an outlet side looper 4, and an outlet side section 5, as shown in FIG. Be divided.

The entry side section 1 has a welding machine for connecting the trailing end of the preceding material and the leading end of the following material, and a pretreatment facility for degreasing the steel sheet.

The central processing section 3 is a portion for subjecting the strip S to the heat treatment or surface treatment which is the object of this line. Of these, the heat treatment section is usually composed of a heating zone 31, a soaking zone 32, and a cooling zone 33, and heats and cools the strip S to give a predetermined heat cycle.

The delivery section 5 has a temper rolling mill, a cutting machine, etc. for straightening the shape of the steel sheet.

Thus, the coiled strip S is dispensed from the entry side section 1 and the desired strip S is obtained.
After the process (1), it is rewound into a coil through the outlet section 5.

The inlet looper 2 is a temporary steel plate storage device for continuously feeding the steel plates to the central processing section 3 even if the inlet section 1 is stopped due to welding or the like.
The exit side looper 4 is also a device having the same purpose, and the entrance side looper 2 and the exit side looper 4 enable continuous processing of steel sheets in the central processing section 3.

[0008]

In the continuous heat treatment line for the steel plate S as described above, the temporary steel plate storage amount, that is, the looper capacity, can secure the entry side handling time such as welding or the exit side handling time such as cutting. Is designed to be.

However, in actual operation, the required time is longer than the handling time assumed at the time of design due to misalignment of automatic equipment in the inlet section 1 and the outlet section 5, delay in roll changing work of the temper rolling mill, and the like. Is often large. Therefore, since the looper allowance will be lost and the line will have to be stopped as it is, the operator appropriately decelerates the strip passing speed of the strip S by looking at the looper remaining amount detection value in order to earn the handling time. After that, when the handling is completed, the acceleration is started.

As described above, in the prior art, the speed control for controlling the remaining amount of the looper has no choice but to depend on the manual operation of the operator, and the advent of a technique capable of achieving the automation of the speed control is desired. It was

Further, the change of the strip passing speed becomes a disturbance to the central processing section 3, and due to a delay in the temperature control operation of the heat treatment section, it often happens that the predetermined heat cycle is exceeded, resulting in a poor yield. It was

The present invention has been made in view of the above-mentioned prior art, and an object of the present invention is to provide a speed control device for a continuous heat treatment line capable of automatically and properly managing the looper remaining amount.

[0013]

According to the structure of the present invention for achieving the above object, a strip passes through an entrance side section, an entrance side looper, a central processing section, an exit side looper and an exit side section in this order. In the speed control device used for the continuous heat treatment line in which the speed at which the strip passes is changed by changing the speed setting value sent to the motor speed control device, the inlet side looper remaining amount detection value and its time change rate detection value or A first fuzzy control calculation unit that calculates and outputs a speed set value or its time change rate by fuzzy calculation from a time change rate calculated value using the entry side looper remaining amount detection value, an output side looper remaining amount detection value, and From the time change rate detection value or the time change rate calculated value using the output looper remaining amount detection value, the speed setting value or the time change rate is calculated by fuzzy calculation. A second fuzzy control calculation unit for outputting, a minimum value calculation unit for calculating the minimum value of the calculation output values of the first and second fuzzy control calculation units, and plate temperature detection at the outlet of the heating zone in the central processing section Third fuzzy control calculation for calculating and outputting a speed setpoint correction amount by fuzzy calculation from the value and the detected time change rate or the calculated time change rate using the detected plate temperature and the target plate temperature for each coil Section, a final fuzzy control output calculating section for calculating the final fuzzy control calculation output by subtracting the calculation output value of the third fuzzy control calculating section from the calculation output of the minimum value calculating section, and the strip running conditions and facility capacity. The target speed calculation unit that calculates the target speed for each coil that is determined from the above, the lower limit speed calculation unit that calculates the plate passing lower limit speed that is determined from the plate passing conditions and facility capacity, and the final fuzzy Your output calculation unit,
It is characterized in that it has an intermediate limiter calculation unit that selects an intermediate value from the calculation outputs of the target speed calculation unit and the lower limit speed calculation unit, and calculates and outputs the selected value to the motor speed control device as a speed set value.

[0014]

According to the present invention having the above-described structure, the speed correction amount by the fuzzy calculation using the minimum value of each fuzzy control output value of the entrance side and exit side loopers and the plate temperature detection value at the exit of the heating zone of the central processing section. Based on the above, the speed of the line is automatically set in consideration of the upper and lower speed limits in operation in the continuous processing line.

[0015]

Embodiments of the present invention will now be described in detail with reference to the drawings.

As shown in FIG. 1, the looper remaining amount detector 1
Numerals 0 and 11 are respectively provided in the inlet and outlet loopers 2 and 4, and are the input and outlet looper residual amount detection values I ₁ , which are signals representing the residual amount of the strip S in each looper 2 and 4.
Send I ₂ respectively. The plate temperature detector 12 is disposed at the outlet of the heating zone 31 (see FIG. 3) of the central processing section 3, and is a signal indicating the plate temperature of the strip S at this outlet portion. _{Send S.} The speed detector 24 includes an entrance looper 2 and a central processing section 3.
And a speed detection value V _r representing the strip passing speed of the strip S during this period.

The speed detector 100 includes a detection value I ₁ (k) and a detection value I ₂ (k) for the inlet and outlet loopers, a heating zone outlet plate temperature detection value T _S (k), and a target at fixed intervals. Plate temperature T
_SSET (k) and speed detection value V _r (k) are input. Note that k is the time of sampling.

The fuzzy control calculators 13 and 14 are provided with input and output looper remaining amount detection values I ₁ (k) and I ₂ (k), respectively.
The speed detection value V _r is input. Fuzzy control computing unit 1
3 is taken as an example, and more specifically, as shown in FIG.
The fuzzy control calculation unit 13 calculates the looper remaining amount detection value I ₁ and the looper remaining amount time change rate calculation value ΔI by the following equation (1).
_{Based on 1} (k) (of course, if there is a looper remaining amount time change rate detector, the detected value may be used as it is. The same applies to the following).
Calculate ₁ (k).

ΔI ₁ (k) = I ₁ (k) −I ₁ (k−1) / Δt (1) where I ₁ (k): Looper remaining amount detection value at time k I ₁ (k− 1): Looper remaining amount detection value at k-1 time point ΔI ₁ (k): Looper remaining amount time change rate calculation value at k time point Δt: Sample period (control period)

Further, the required speed value V is calculated by the following equation (2).
Calculate ₁ (k). V ₁ (k) = V _r (k) + ΔV ₁ (k) * Δt (2) Here, V _r (k): speed detection value at time k ΔV ₁ (k): speed set value time at time k Change rate V ₁ (k): Required value of speed at time k

Since the fuzzy operation is performed by a known method, detailed description thereof will be omitted. For example, the following is a description of what the human being actually judges and operates (fuzzy rule) by a mathematical expression and algorithmizes it. There is.

When "the remaining amount of the looper is" small "and" is gradually decreasing ", the speed is" slightly decreased ". ]

However, although not shown, the remaining amount of the looper becomes extremely small, and necessary safety measures such as line stop are taken before mechanically hitting the stopper.

The fuzzy control calculation unit 14 for managing the remaining amount of the looper on the output side outputs the required value V ₂ (k) of the speed with the same processing contents as the fuzzy control calculation unit 13.

The minimum value calculation unit 16 obtains the minimum value V ₁₂ (k) of the required values V ₁ (k) and V ₂ (k) which are the fuzzy control calculation output values. That is, the case is considered in which the deceleration requests are made simultaneously from the entrance side and exit side looper remaining amount management.

Although not shown, heating of the heat treatment part
The cooling condition is set based on the minimum value V ₁₂ (k).

The fuzzy control calculator 15 manages the heating zone outlet plate temperature. That is, the difference between the heating zone outlet plate temperature detection value T _S (k) and the target plate temperature T _SSET (k) determined for each coil and the speed and the time change rate of the difference are calculated by fuzzy calculation.
The speed set value correction amount ΔV _S (k) is calculated.

The final fuzzy control output computing unit 25 computes the following equation (3) to obtain the final fuzzy control output V _F (k)
Ask for.

V _F (k) = V ₁₂ (k) −ΔV _S (k) (3) where ΔV _S (k) ≧ 0

If ΔV _S (k)> 0 from the equation (3), the heating zone outlet plate temperature rises from the current value. In other words, even if the heating zone outlet plate temperature temporarily fluctuates due to a poor adjustment of the fuzzy control calculation units 13 and 14, operation can be performed without breaking the allowable lower limit of the target heat cycle which causes a problem in heat treatment.

Needless to say, the so-called fuzzy rules differ for each of the fuzzy control calculation units 13-15.

The target speed calculation unit 17 calculates and outputs a target speed V _MAX for each coil based on the plate size, required heat cycle and other plate passing conditions and facility capacity.

The lower limit speed calculation unit 18 calculates and outputs, for each coil, a lower limit speed V _MIN that does not cause buckling, based on equipment capacity and plate passing conditions such as plate size.

The intermediate limiter calculation unit 19 checks the upper and lower limits of the fuzzy control output V _F (k) and calculates and outputs the speed command value V _S (k) to be actually given to the motor speed control device 20. That is, since V _MAX > V _MIN , the speed command value V _S (k) is obtained from the following equations (4) to (6). I) When V _F (k)> V _MAX V _S (k) = V _MAX (4) II) When V _F (k) <V _MIN V _S (k) = V _MIN (5) III) other _{V S (k) = V F} (k) ... (6)

The motor speed control device 20 operates the drive motor 23 of the entrance-side bridle roll 21 or the exit-side bridle roll 22 so that the line speed becomes V _S (k).

In the above embodiment, the fuzzy control method is employed as a method for expressing and automating the manual operation performed by the intuition and experience of the operator by a mathematical expression, and managing the remaining amount of the looper. That is, although the remaining amount of the looper is initially controlled by decelerating the speed, when the entrance looper 2 and the exit looper 4 operate at the same time, that is, considering that the deceleration operation is necessary due to a plurality of factors, Take the minimum value of each fuzzy control output value.

Further, the outlet plate temperature of the heating zone 31 which is the most important in heat treatment is detected, and the allowable heat cycle range is smaller than the target value on the low temperature side and larger on the high temperature side. If the detected value becomes equal to or lower than the target value, the speed correction amount is obtained by fuzzy calculation using the plate temperature detected value, and the speed set value is further reduced below the minimum value, and the heating zone outlet plate temperature is higher than the target value. Normalize. Also, the upper and lower limits are kept at the maximum and minimum speeds for operation.

[0038]

As described above in detail with reference to the embodiments, according to the present invention, the speed for controlling the remaining amount of the looper on the inlet side or the outlet side of the continuous heat treatment line, which conventionally had to rely on manual operation. Operations can be performed automatically while ensuring target heat cycle conditions. That is, it is possible to automatically perform the operation that realizes the function equal to or more than the manual operation and exhibits the effect, and it is possible to facilitate the operation and save the labor.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram illustrating processing contents of a fuzzy control calculation unit.

FIG. 3 is an overall configuration diagram of a continuous heat treatment line.

[Explanation of symbols]

 2 Inlet looper 3 Central processing section 4 Outlet looper 10 Inlet looper residual amount detector 11 Outgoing looper residual amount detector 12 Heating zone outlet plate temperature detector 13 to 15 Fuzzy control arithmetic unit 16 Minimum value arithmetic unit 17 Target Speed calculator 18 Lower limit speed calculator 19 Intermediate limiter calculator 20 Motor speed controller 25 Final fuzzy control output calculator 31 Heating zone 100 Speed controller S strip

Claims (1)

[Claims] 1. A strip is made to pass through an entrance side section, an entrance side looper, a central processing section, an exit side looper and an exit side section in order, and a speed set value sent to a motor speed control device is changed to thereby strip the strip. In the speed control device used for the continuous heat treatment line that changes the speed at which the sheet passes, the inlet looper remaining amount detection value and its time change rate detection value or the time change rate calculated value using the inlet side looper remaining amount detection value From the first fuzzy control calculation unit that calculates and outputs the speed set value or its time change rate by fuzzy calculation, the output side looper remaining amount detection value, and its time change rate detection value or the output side looper remaining amount detection value A second fuzzy control calculation unit for calculating and outputting a speed setting value or its time change rate by fuzzy calculation from a time change rate calculated value using 2. A minimum value calculation unit that calculates the minimum value of the calculation output value of the fuzzy control calculation unit, a plate temperature detection value at the outlet of the heating zone in the central processing section, and a time change rate detection value or the plate temperature detection value From the calculated rate of change over time and the target plate temperature for each coil,
A third fuzzy control arithmetic unit for arithmetically outputting the speed setting value correction amount by fuzzy arithmetic, and a final fuzzy control arithmetic operation by subtracting the arithmetic output value of the third fuzzy control arithmetic unit from the arithmetic output of the minimum value arithmetic unit. Final fuzzy control output calculation unit that calculates the output, target speed calculation unit that calculates the target speed for each coil that is determined based on the strip running conditions and facility capacity, etc. Selects an intermediate value from the lower limit speed calculation unit that calculates the lower limit speed, the final fuzzy control output calculation unit, the target speed calculation unit, and the calculation output of the lower limit speed calculation unit, and sets the selected value to the motor speed control device. A speed control device for a continuous heat treatment line, comprising: an intermediate limiter operation unit that outputs an operation as a value.