A method and system for tracking and synchronizing measurement values ​​and positions of cold-rolled strip steel.

Abstract

This invention provides a method and system for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. It is used in scenarios where there is a significant and uncertain operational delay between the detection instrument and the actuator. The method employs strip steel position calculation and shift register to synchronize the strip steel measurement values ​​with the strip steel position. The system includes the following: the distance from the detection instrument to the actuator is d, divided into N equal segments, each segment being a step length s; the number of delay steps N includes the system delay step number N. τ and running delay steps N R In the program, a shift register of length N is established to store the strip measurement values. Each register stores the strip measurement value corresponding to each step position s. In the k-th cycle, the number of shift steps N is first calculated. T Perform the shift operation in first-in-first-out order; calculate the system delay N steps. τ Write the measured value to address 1 to (N) τ +N T The measurement value is read from the register of the Nth register, which is the strip measurement value at the actuator.

Description

Technical Field

[0001] This invention relates to the field of metallurgical automation technology, and in particular to a method and system for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. Background Technology

[0002] In cold rolling production lines, due to operating conditions, the distance between the detection instruments and actuators is relatively large, resulting in significant lead and lag delays in the detection signals, affecting the performance of the control system. This paper proposes a method for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. This method addresses scenarios where there is a significant and uncertain delay between the detection instruments and actuators. It employs strip position calculation and shift register methods to synchronize the strip steel measurement values ​​with its position. When the detection instruments are used for feedforward control, they are installed before the actuators, resulting in a lead effect in the detection signals. This method tracks the detection signals to the actuator position, achieving position synchronization and improving the accuracy of the feedforward control. When the detection instruments are installed for feedback control, they are installed after the actuators, resulting in a lag effect in the detection signals. The control quantity is recorded at the actuator position, and the soft measurement value of the controlled variable is calculated using a mathematical model of the controlled object. This method tracks the measured value to the detection instrument position, achieving soft measurement value position synchronization. Feedback control is then performed using the soft measurement value and the actual measurement value, improving the accuracy of the feedback control. Summary of the Invention

[0003] To address the technical problems raised in the background art, this invention provides a method and system for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. This system is used to detect scenarios where there is a large operating delay between the instrument and the actuator, and the delay time is uncertain. The method employs strip steel position calculation and shift register to synchronize the strip steel measurement values ​​and the strip steel position.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] A method for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel includes the following:

[0006] 1) The distance from the measuring instrument to the actuator is d, which is divided into N equal segments, each segment having a length of one step s;

[0007] 2) Set the program cycle period to T. The strip running distance within the program cycle period T shall not be less than 1 step s, i.e., s≥v*T; the control program shall be executed cyclically in the form of a timer interrupt, where v is the strip running speed.

[0008] 3) Let N be the number of delay steps; the number of delay steps N includes the system delay steps N. τ and running delay steps N R ,Right now:

[0009] N = N τ +NR ;

[0010] The delay step number N is a constant designed based on the distance between the detection instrument and the actuator and the program cycle requirements; the running delay step number N R It is the number of steps corresponding to the running time of the strip from the detection instrument to the actuator; the system delay steps N τ It is the number of delay steps corresponding to the system time constant τ(s);

[0011] 4) Calculate the system delay steps N τ :

[0012]

[0013] 5) The number of shift steps is N T It is the number of steps corresponding to the program loop cycle, and the number of shift steps is calculated as N. T :

[0014]

[0015] Run delay steps N R Not less than the number of shift steps N T N R ≥N T ;

[0016] 6) In the program, a shift register of length N is created to store the strip measurement values. Each register stores the strip measurement value at each step position s.

[0017] 7) In the kth cycle, first calculate the number of shift steps N. T Perform the shift operation in first-in-first-out order; calculate the system delay N steps. τ Write the measured value to address 1 to (N) τ +N T The measurement value is read from the register of the Nth register, which is the strip measurement value at the actuator.

[0018] Furthermore, the system time constant includes the time constant of the detection instrument and the time constant of the actuator.

[0019] Furthermore, the program loop period T ranges from 0.001 to 1 second.

[0020] Furthermore, the step size s ranges from 0.01 to 0.2 m.

[0021] The present invention also provides a system for tracking and synchronizing the measurement values ​​of cold-rolled strip steel. The system includes a primary PLC control system and a secondary host computer system connected thereto. The method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel is loaded into the programs of the primary PLC control system and the secondary host computer system.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] This invention employs a method and system for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. It addresses scenarios where there is a significant and uncertain operational delay between the detection instrument and the actuator. The method utilizes strip steel position calculation and shift register to synchronize the strip steel measurement values ​​with its position. When the detection instrument is used for feedforward control, it is installed before the actuator, resulting in a leading effect on the detection signal. This method tracks the detection signal to the actuator position, achieving position synchronization and improving the accuracy of the system's feedforward control. When the detection instrument is installed for feedback control, it is installed after the actuator, resulting in a lagging effect on the detection signal. The control quantity is recorded at the actuator position, and the soft measurement value of the controlled quantity is calculated using a mathematical model of the controlled object. This method tracks the measured value to the detection instrument position, achieving soft measurement value position synchronization. Feedback control is then performed using the soft measurement value and the actual measurement value, improving the accuracy of the system's feedback control. Attached Figure Description

[0024] Figure 1 This is an embodiment of a method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel according to the present invention. Detailed Implementation

[0025] The specific embodiments provided by the present invention will be described in detail below with reference to the accompanying drawings.

[0026] A method for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel, specifically including the following:

[0027] 1. The distance from the measuring instrument to the actuator is d (m), which is divided into N equal segments, each segment having a length of one step s (m).

[0028] 2. The strip running distance within the program cycle is not less than 1 step, i.e., s≥v*T; the control program is executed cyclically in the form of a timer interrupt, the program cycle is T(s), and the value range is 0.001~1s; v(m / s) is the strip running speed, and the value range is 1~20m / s; the step range is 0.001~20m.

[0029] 3. N represents the delay step count; the delay step count N includes the system delay step count N. τ and running delay steps N R That is, N = N τ +N RThe delay step number N is a constant designed based on the distance between the detection instrument and the actuator and the program cycle requirements; the running delay step number N R It is the number of steps corresponding to the running time of the strip from the detection instrument to the actuator; the system delay steps N τ It is the number of delay steps corresponding to the system time constant τ(s). The system time constant includes the time constant of the detection instrument and the time constant of the actuator.

[0030] 4. Calculate the system delay steps N τ :

[0031]

[0032] 5. Calculate the number of shift steps N T :

[0033]

[0034] The number of shift steps is N T It is the number of steps corresponding to the program's loop cycle, and the running delay step N. R Not less than the number of shift steps N T N R ≥N T .

[0035] 6. In the program, a shift register of length N is established to store the strip measurement values. Each register stores the strip measurement value corresponding to each step position.

[0036] 7. In the k-th cycle, first calculate the number of shift steps N. T Perform the shift operation in first-in-first-out order; calculate the system delay N steps. τ Write the measured value to address 1 to (N) τ +N T The measurement value is read from the register of the Nth register, which is the strip measurement value at the actuator. [Specific Implementation Examples]

[0038] like Figure 1 As shown, this method is used for thickness measurement tracking and position synchronization in cold rolling feedforward thickness control; the detection instrument is a thickness gauge, and the actuator is a hydraulic roll gap.

[0039] 1. The distance from the measuring instrument to the actuator is d, which is divided into N equal segments, each segment having a length of one step s (m).

[0040] N is the delay step number; the strip running distance within the program cycle is not less than 1 step, i.e., s ≥ v * T; the control program executes cyclically according to the timer interrupt method, the program cycle is T(s), the value range is 0.001~1s, and the program cycle is set to T(s) = 0.01s; the strip running speed v(m / s) is set by the production process, the value range is 1~20m / s; the strip running distance within the program cycle is not less than 1 step, i.e., s ≥ v * T, the step range is 0.01~0.2m, and the step is set to s = 0.01m; d = 3m, delay step number N = 300; the delay step number N includes the system delay step number N. τ and running delay steps N R That is, N = N τ +N R The number of shift steps is N. T It is the number of steps corresponding to the program's loop cycle, and the running delay step N. R Not less than the number of shift steps N T N R ≥N T System delay steps N τ It is the number of delay steps corresponding to the system time constant τ(s). The system time constant includes the time constant of the detection instrument and the time constant of the actuator; the detection time constant of the thickness gauge is 0.07s, the time constant of the hydraulic roll gap actuator is 0.03s, and the system time constant τ(s) is 0.1s.

[0041] 2. Calculate the system delay steps N τ :

[0042]

[0043] N τ The value range is 10 to 200;

[0044] 3. Calculate the number of shift steps as N T :

[0045]

[0046] N T The value range is 1 to 20;

[0047] 4. In the program, a shift register of length N is established to store the strip measurement values. Each register stores the strip measurement value corresponding to each step position.

[0048] 5. In the k-th cycle, first calculate the number of shift steps N. T Perform the cyclic shift operation in first-in-first-out order; then calculate the system delay N. τ Write the measured value to address 1 to (N) τ +N TThe value of the strip at the actuator is read from the register of the Nth register; when the strip speed is 1 m / s, N τ =10, N T =1, write the measured value into registers with addresses 1 to 11; N R =290. After 290 shift operations, the measured value of the detection instrument reaches the actuator; the measured value read from the register at address 300 is the strip measurement value at the actuator position.

[0049] The present invention also provides a system for tracking and synchronizing the measurement values ​​of cold-rolled strip steel. The system includes a primary PLC control system and a secondary host computer system connected thereto. The method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel is loaded into the programs of the primary PLC control system and the secondary host computer system.

[0050] This invention employs a method and system for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel. It addresses scenarios where there is a significant and uncertain operational delay between the detection instrument and the actuator. The method utilizes strip steel position calculation and shift register to synchronize the strip steel measurement values ​​with its position. When the detection instrument is used for feedforward control, it is installed before the actuator, resulting in a leading effect on the detection signal. This method tracks the detection signal to the actuator position, achieving position synchronization and improving the accuracy of the system's feedforward control. When the detection instrument is installed for feedback control, it is installed after the actuator, resulting in a lagging effect on the detection signal. The control quantity is recorded at the actuator position, and the soft measurement value of the controlled quantity is calculated using a mathematical model of the controlled object. This method tracks the measured value to the detection instrument position, achieving soft measurement value position synchronization. Feedback control is then performed using the soft measurement value and the actual measurement value, improving the accuracy of the system's feedback control.

[0051] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0052] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for tracking and synchronizing the measurement values ​​and position of cold-rolled strip steel, characterized in that, Including the following: 1) The distance from the measuring instrument to the actuator is d, which is divided into N equal segments, each segment having a length of one step s; 2) Set the program cycle period to T. Within the program cycle period T, the strip running distance shall not be less than one step s, i.e., s≤v T; The control program executes cyclically using a timer interrupt method, where v is the strip speed. 3) N is the number of delay steps; the number of delay steps N includes the number of system delay steps N τ and the number of running delay steps N R i.e.: N= +N R ; The delay step number N is a constant designed based on the distance between the detection instrument and the actuator and the program cycle requirements; the running delay step number N R It is the number of steps corresponding to the running time of the strip from the detection instrument to the actuator; system delay steps. It is the number of delay steps corresponding to the system time constant τ; 4) Calculate the system delay steps : 5) shift step number is N T is the program loop period corresponding to the step number, and the shift step number is N T : Running delay step number N R Not less than shift step number is N T That is, N R ≥ N T ; 6) In the program, a shift register of length N is created to store the strip measurement values. Each register stores the strip measurement value corresponding to each step position s. 7) In the kth cycle, first calculate the number of shift steps N. T The shift operation is performed in first-in, first-out order; Calculate system delay steps Write the measured value to address 1~( +N T The measurement value is read from the register of the Nth register, which is the strip measurement value at the actuator. The system time constant τ includes the time constant of the detection instrument and the time constant of the actuator.

2. The method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel according to claim 1, characterized in that, The program loop period T ranges from 0.001 to 1 second.

3. The method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel according to claim 1, characterized in that, The step size s ranges from 0.01 to 0.2 m.

4. The system for tracking and synchronizing the measurement values ​​of cold-rolled strip steel according to claim 1, characterized in that, The system includes a primary PLC control system and a secondary host computer system connected thereto, wherein the method for tracking and synchronizing the measurement values ​​of cold-rolled strip steel is loaded into the programs of the primary PLC control system and the secondary host computer system.

Images