JPH02254111A - Method for controlling bellless charging equipment in blast furnace - Google Patents

Abstract

PURPOSE:To control opening degree of raw material flow rate control valve in charging equipment at high accuracy by using feedback correcting quantity based on the past actual results and feedforward correcting quantity based on characteristic of raw material at this time to correct a reference opening degree. CONSTITUTION:In the bellless charging equipment providing a swinging chuter in a blast furnace, the reference opening degree function is obtd. from relation between charging velocity based on the actual results and the opening degree of the raw material flow rate control valve in a lower bunker. On the other hand, the target charging velocity is calculated from weight of the charging raw material at this time and set times of swinging in the swinging chuter. By using the above reference opening degree function, the reference opening degree of the above raw material flow rate control valve corresponding to the target charging velocity is obtd. Successively, the feedback correcting quantity at this time is obtd. from the previous feedfack correcting quantity error. On the other hand, the feedforward correcting quantity is obtd., based on a relational approximate expression of discharged weight and discharge time of the raw material from a hopper in the actual results and the discharged weight and discharge time of the charged raw material at this time. Both correction quantities are added to the above reference opening degree, and the opening degree command value for the raw material flow rate control valve is obtd. and based on this, the opening degree is adjusted to execute charging control.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for controlling a blast furnace bellless charging equipment.

[Conventional technology] The material flow rate adjustment valve (hereinafter referred to as FC) of conventional blast furnace bellless charging equipment
The opening degree (referred to as C) is controlled by the following method.

For example, the control method disclosed in Japanese Patent Application Laid-Open No. 8CI-4B80B measures the weight inside the lower bunker with a load cell or the like while discharging the raw material, and controls the opening degree of the FCC to match the target weight pattern. ing.

In addition, the control method disclosed in Japanese Patent Application Laid-open No. 6l-2389H calculates the amount of opening correction based on the difference between the discharge time of multiple charges in the past and the set value, and The opening degree of the FCC is controlled by correcting the

In addition, we have multiple data on the discharge time of the laser ping hopper, etc. and the discharge time at the lower bunker, and linearly regress these relationships for each FCC opening.2. There is also a control method in which the opening degree of the FCC is controlled from the discharge time of the hopper etc. based on this relationship (hereinafter referred to as feedforward control).

[Problems to be Solved by the Invention] The control method disclosed in JP-A No. 80-48306 as described above requires that the furnace body and lower bunker for high-pressure operation are integrated; Since changes in the furnace internal pressure cause disturbances, it is difficult to measure the weight of the lower bunker at a high degree of tl'i, and therefore there is a problem in that sufficient control accuracy cannot be obtained.

In addition, in the control method disclosed in JP-A No. 11iI-238906, the obtained corrected data is used for the next control data, so it is difficult to follow changes in FCG flow characteristics due to changes in raw material properties. It was difficult. In addition, in feedforward control, it is necessary to check whether it is possible to follow changes in the properties of raw materials, and to check the discharge time and FCC of laser pins, etc.
Control accuracy was determined by the accuracy of the relational expression, and sufficient accuracy was not obtained.

This invention was made in order to solve such problems, and is a blast furnace that can control the opening degree of the FCG with high precision and make it possible to match the starting point and ending point of raw material 1-1 charging. The purpose is to obtain a control method for bellless charging equipment.

[Means for Solving the Problems] The control method for blast furnace bellless charging equipment according to the present invention includes a step of generating a reference opening degree function from the relationship between the charging speed and the opening degree of the FCC based on actual performance, and The method includes a step of determining a target charging speed from the weight of the raw material to be input and the number of turns by the rotating shooter, and a step of determining a standard opening of the FCC from the standard opening function and the target charging speed.

Furthermore, there is a step of calculating the feedback correction amount based on the previous charging speed, the previous target charging speed, the reference opening function, and the previous feedback correction amount, and the process of calculating the weight and time of material discharged from the hopper based on the actual results. An approximate expression representing the relationship between the two is obtained from the above] and a step of obtaining a feedforward correction amount based on the weight and time of discharge of the raw material to be charged this time from the hopper, and the approximate expression.

Furthermore, a step of determining an FCC opening command value based on the FCG reference opening, feedback correction amount, and feedforward correction amount, and adjusting the FCC opening based on this opening command value is performed.

[Function] In this invention, in addition to determining the standard opening degree of the FCC,
A feedback correction amount is determined based on past results, a feedforward correction amount is determined based on the properties of the raw material to be charged this time, and the reference opening is corrected to determine the FCC opening command value.

Then, the opening degree of the FCC is adjusted based on this FCGO opening degree command value. By adjusting the opening of the FCC, the charging speed of raw materials can be appropriately controlled.

[Embodiment] FIG. 1 is an explanatory diagram of a control device and related equipment that implement a method according to an embodiment of the present invention. In the figure, (1
0) is the lower bunker, (1j) is the lower bunker (10)
This is the FCC established under the FCC. (12) is the top of the blast furnace, and (13) is a rotating shaft installed inside the furnace. (
14) is a weighing hopper, and the raw material discharged from the weighing hopper (14) is conveyed by a belt conveyor (not shown) and carried into the lower bunker (10), where it is transferred to the F CC
(11) and is charged into the furnace by the rotating operation of the rotating unit (3) in the furnace.

(20) measures the FCG opening degree and detects the opening degree of FCG (11). (21) is a raw material passage sensor that detects the start and end of raw material charging. (22) is a load cell that detects the weight of the raw material discharged from the weighing hopper (14).

(30) is the charging time measurement circuit, and the raw material passage sensor (2)
) The raw material charging time is measured based on the output.

(31) is a charging speed calculating circuit which calculates the charging speed of the raw material based on the charging weight from the load cell (22) and the charging time from the charging time measuring circuit (30).

(50) is the data file, charging speed g-1 side circuit (
Charging speed information from 31) and FCC opening degree 11 (20)
Accumulate opening degree information from the FCC and constantly file performance data of charging speed and FCC opening degree. The contents of the data file at this time are, for example, the opening range (1
0'), the charging speed data is filed every 0.1''.

(51) is a calculation device, which calculates the average value of the charging speed for each opening degree based on the data of the data file (50), and then calculates the charging speed as shown in FIG. 3(A). A scatter diagram of the opening degree is created, and a reference opening function is generated that approximates the scatter diagram to a curve (for example, a cubic function) as shown in FIG. 3(B). For example, a function shown in the following equation is generated.

θ=av +bv2+cv+d (1)(3
2) is a target speed calculation circuit, which calculates the target charging by VQ - charging weight - (fixed number of turns x 1 turning time) based on the charging weight and the preset number of turns of the turning shooter. Find the speed VQ. (33) is a reference opening calculation circuit, which calculates the reference opening θ0 of the FCC according to the following equation based on the target charging speed vo and the reference opening function from the calculation device (51).

vo = avo + bvo2 + cvo + d (2
) (35) is a changeover switch, which is used for automatic control using the reference opening θ0 from the reference opening calculation circuit (33) as a control signal, and for control based on a predetermined FCG opening setting without automatic control. Select alternatively. In this embodiment, a case where automatic control is selected will be described below. (35) and (3G) are buffers, respectively. The buffer (35) stores the previous actual charging speed, and the buffer (36) stores the previous target charging speed.

(37) is a foot-hack correction amount calculation circuit (hereinafter referred to as FB correction amount calculation circuit), which calculates the feedback correction amount (hereinafter referred to as FB correction amount) Δθ1 by the following calculation.

Fig. 4 is an explanatory diagram for calculating the FB correction amount △θJ. First, the error △■ during the previous charging of the same brand is calculated by reading the data from Hasofa (35) and (3G) and using the following formula. demand.

△V - Previous actual charging speed Previous target charging speed (3) Then, from this △V and the reference opening degree θo (-f (vo)) for the current target charging speed VQ, correct the error using the following formula. Determine the subsequent reference opening degree of 00°.

θ0'-f(vo-ΔV) (4) The standard opening degree correction amount (theoretical value) Δθ01 is determined by the following formula.

Δθo1−θ0°−θo(5) Next, the FB correction value Δθ1 is determined from this Δθo1, the correction gain G1 (0 to 1), and the previous FB correction amount.

Δθ1=G1. X△θ01 + previous FB correction amount (3B) is the discharge time meter 1tIIJ circuit, and the load cell (22)
The raw material discharge time is calculated based on the output of fllll+.

(52) is a data file that contains discharge time information from the ujlff 1n measuring circuit (38) and the load cell (
22) is stored, and data regarding the relationship between the two is accumulated. The contents of the data at this time are, for example, as shown in Fig. 5, and the latest data is stored for each raw material brand, for example, 3000 pieces, regarding the relationship between the discharge weight of the lowering scale and the discharge weight of 1jjl for each raw material brand. There is.

(53) is an arithmetic circuit that creates a scatter diagram of discharge time against weight as shown in Figure 6 (A) based on the data in the data file (52), and as shown in Figure 6 (B). For example, the scatter diagram is approximated by a straight line as shown in the following equation.

ω−αt+β (7) (39)
is a feedforward correction amount calculation circuit (hereinafter referred to as FF correction amount calculation circuit), which calculates the current discharge speed α'' based on the current charging weight ω′ and the discharge time t° using the following equation.

α'=(ω゛-β) / t' (8
) Next, the current target charging speed v is determined from the ratio α′/α of this discharge speed α′ to the standard JJl output speed change speed.

The expected speed ■° of t1 when charging is performed at the standard opening degree Oo (-f (vo)) for the reference opening degree Oo (-f (vo)) is determined, and the predicted speed error ΔV is also determined.

v = voxa'/a (9) Δv
= v' -vo (10) Next, from this △V, perform the same calculation as the FB correction amount calculation to find the correction amount (theoretical value) △θo2, and calculate this △θ02 and the correction gain G2 (0 to 1). The feedforward correction amount (hereinafter referred to as FF correction amount) Δθ2 is determined by the following.

△θ2−G2 X△θ02 (i l
) (40) is an arithmetic/control circuit, and a selection switch (
Add the reference opening θ0 selected in step 34), the FB correction amount △θ1 from the FB correction amount calculation circuit (37), and the FF correction amount △θ2 from the FF correction amount calculation circuit (39), and perform the addition. The resulting signal (=θ0+θI+02) is output to the drive device (not shown) as the FCC opening command value.

In the embodiment configured as described above, the pig file (5o) has accumulated performance data showing the relationship between the charging speed and the opening degree of the FCC, and the calculation device (51) operates based on the data. Find the standard opening function using equation (1),
The reference opening degree generation circuit (33) calculates the FCG reference opening degree θ using equation (2) based on the reference opening degree function and the target charging speed VQ.
Find 0.

The FB correction amount calculation circuit (37) includes a buffer (37), (
The difference between the previous charging speed from 311t) and the previous []] target speed is determined by equation (3), and the FB correction amount Δθ1 is determined by equations (4) to (6).

On the other hand, the data file (52) is the weighing potper (I4).
Actual data showing the relationship between the discharge weight and the discharge time is accumulated, and the arithmetic circuit (53) calculates (
7) An approximate expression representing the relationship between the discharge time and the discharge weight is obtained. Then, the FF correction amount calculation circuit (39) is (4)
, (5), (8) ~ (lO) formula, FF correction amount △
Find θ2.

The FCG standard opening degree θo, F obtained as described in
The B correction amount Δθ1 and the FF correction amount Δθ2 are added by the calculation/control circuit (40), and the added value is supplied as the FCC opening command value to the drive circuit (not shown) of the FCG (11). Adjust the opening of FC (1, 1,).

As described above, the FB correction amount θ is calculated based on the previous performance.
1 is calculated, feedback control is performed based on this, and correction is performed based on past results.Furthermore, the FF correction amount θ2 is calculated based on the properties of the raw material to be charged this time, and feedforward correction is performed using that. The raw material charging speed can be properly controlled, the raw material charging start point and the raw material charging end point can be matched, and the raw material can be charged uniformly.

Note that it is not necessary to output the outputs of the calculation circuits (51) and (53) every time, and the outputs of the data files (50) (52)
It is only necessary to output the data after a certain amount of new data has been accumulated in the
l), (S2) should be closed. Further, when the correction using the FB correction amount and the FF correction amount is not performed, the switches (S; 3) and (S4) are opened.

In addition, in the above embodiment, the data file (
50), (52) and arithmetic circuits (51), (5
3) can be included in the process computer, and the others can be included in the charging control device. In that case, each arithmetic circuit, etc. can be realized by itself as a hardware configuration, but it is possible to implement it in the computer software. Needless to say, this can also be achieved by

[Effects of the Invention] As described above, according to the present invention, the FB correction amount is determined based on past results, and the FF correction amount is determined based on the properties of the raw material to be charged this time to correct the standard opening degree. This makes it possible to control according to the properties of the raw material, making highly accurate control possible.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing an apparatus and related equipment for implementing a method according to an embodiment of the present invention, and Fig. 2 is a data file showing the relationship between FCC opening degree and charging speed for a certain raw material brand. Content explanatory diagram, Figure 3 (A) (B) is a characteristic diagram showing the relationship between average charging speed and FCC opening degree, Figure 4 is F
B: An explanatory diagram of how to calculate the correction value. Figure 5 is an explanatory diagram of the data file showing the relationship between discharge weight and discharge time.
Figures (A) and (B) are characteristic diagrams showing the relationship between the evacuation time of υ1 and the discharge weight, and FIG. 7 is an explanatory diagram for determining the relationship between the discharge weight of the raw material and the discharge time. In the figure, (10) is the lower bunker, (11) is the FC
C, (+3) is a rotating shooter, and (14) is a Ho Sonokoo.

Claims (1)

[Claims] A step of generating a reference opening function from the relationship between the charging speed based on actual results and the opening of the raw material flow rate control valve, and from the weight of the raw material to be charged this time and the set rotation number of the rotating chute. A step of determining the target charging speed, a step of determining the standard opening of the raw material flow control valve from the standard opening function and the target charging speed, and a step of calculating the previous charging speed, the previous target charging speed, and the standard opening function. There is also a process of calculating the feedback correction amount based on the previous feedback correction amount, a process of calculating an approximate formula showing the relationship between the weight and discharge time of the raw material from the hopper based on the actual results, and a process of calculating the amount of raw material to be charged this time. a step of determining the feedforward correction amount based on the discharge weight and discharge time from the hopper, and the approximate formula; 1. A control method for blast furnace bellless charging equipment, comprising the steps of determining an opening command value and adjusting the opening of a raw material flow rate regulating valve based on the opening command value of the raw material flow rate regulating valve.