Temper mill on-line roll changing cylinder synchronous control system and control method

[0044] The technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments to further understand the purpose, solutions and effects of the present invention, but not as a limitation of the protection scope of the appended claims of the present invention.

[0045] Refer to figure 2 The structural block diagram of the online roller changing cylinder synchronization control system of the leveling machine of the present invention is shown in the figure. The online roller changing cylinder synchronization control system 50 of the leveling machine of the present invention is combined with the hydraulic system of the online roller changing of the leveling machine. The hydraulic system includes a plurality of hydraulic cylinders 61, 62, 63, 64 arranged in parallel, the control system 50 includes a plurality of hydraulic cylinder position detection modules 551, 552, 553, 554, an A/D input module 51, a PLC controller 52, D/A output module 53, amplifier 54, and multiple control valves 561, 562, 563, 564. The hydraulic cylinder position detection modules 551, 552, 553, and 554 are respectively arranged on the hydraulic cylinders 61, 62, 63, and 64. The hydraulic cylinder position detection modules 551, 552, 553, and 554 can use common sensors; A/ The D input module 51 is connected to the hydraulic cylinder position detection modules 551, 552, 553, and 554, respectively, to collect the actual position value of each hydraulic cylinder; the PLC controller 52 is connected to the A/D input module 51 for The actual position value fed back from the D input module 51 is subjected to PID calculation with a set value and the calculation result value is compared with a limit range value to obtain a limiting output value; the D/A output module 53 is connected to the PLC controller 52, It is used to output the limiting output value; the amplifier 54 is connected to the D/A output module 53, for receiving the limiting output value transmitted by the D/A output module 53 and amplifying the limiting output value; control valve 561, 562, 563, and 564 are respectively connected to hydraulic cylinders 61, 62, 63, and 64, and control valves 561, 562, 563, and 564 are respectively connected to amplifier 54. Each control valve is used to adjust according to the amplified limiting output value. The movement of its spool is to control the lifting speed and position of the hydraulic cylinder connected to it. Among them, the PLC controller averages multiple actual position values, subtracts the actual position value of each hydraulic cylinder from the average value, multiplies it by a hydraulic cylinder synchronization coefficient, and normalizes the result value. To obtain the limit range value, it should be noted that the limit range value here refers to a value between a lower limit value and an upper limit value, such as -10 to 10, when the PID calculation result value When the value exceeds the limit range value, the limit output value is the upper limit value of the limit range value or the lower limit value of the limit range value. For example, the limit range value is -10~10. For example, when the PID operation result value is 12, the limit output value is 10, and when the PID operation result value is -12, the limit output value is -10. When the PID operation result value is within the limit range value, the limit output value is the PID operation result value.

[0046] Preferably, the PLC controller 52 is an anti-integral saturation PID controller. The amplifier 54 is an electro-hydraulic servo amplifier board, and the control valves 561, 562, 563, and 564 are electro-hydraulic servo valves.

[0047] Further, the above-mentioned set value is the height value of the outer rail of the leveler, and the outer rail of the leveler here is the roller changing carriage rail 24 in the introduction of the background art.

[0048] Such as image 3 As shown, when the above-mentioned control system is used to synchronously control the on-line roll changing cylinder of the leveling machine, it includes:

[0049] Step S1: Collect the actual position value of each hydraulic cylinder;

[0050] Step S2: The PLC controller performs PID calculation on the actual position value and a set value, and compares the calculation result value with a limit range value to obtain a limiter output value (corresponding to the hydraulic cylinder 61, 62, 63 mentioned above) 64. The LC controller will perform PID calculations on each actual position value and a set value and compare the calculation result value with a limit range value to obtain a limiting output value, that is, each of the four hydraulic cylinders Form a closed loop control loop);

[0051] Step S3: The D/A output module outputs the limiting output value to the amplifier;

[0052] Step S4: the amplifier amplifies the limiting output value and outputs it to multiple control valves respectively;

[0053] Step S5: Each control valve adjusts the movement of its spool according to the amplified limiting output value to control the lifting speed and position following of the hydraulic cylinder connected to it.

[0054] In the step S2, the PLC controller averages multiple actual position values, that is, S average =(S1+S2+S3+S4)/4, the actual position value of each hydraulic cylinder is subtracted from the average value, and then multiplied by a hydraulic cylinder synchronization coefficient k, and the result value is normalized To obtain the limit range value, when the PID operation result value exceeds the limit range value, the limit output value is the upper limit value of the limit range value or the lower limit value of the limit range value , When the PID calculation result value is within the limit range value, the limit output value is the PID calculation result value, wherein the value of the hydraulic cylinder synchronization coefficient k can be adjusted according to actual conditions, such as 0.5~ Adjust within the range of 3.0. It can be seen from the acquisition of the above limit range values ​​that although the four hydraulic cylinders each form a closed loop control circuit, the four hydraulic cylinders restrict each other.

[0055] Preferably, in the step S3, an additional value superimposing step is further included. In the additional value superimposing step, an additional value can be added to the aforementioned calculation result value according to the actual corresponding speed of the hydraulic cylinder to eliminate zero point drift , Output characteristic difference and other influences.

[0056] It can be seen from the above that figure 2 The four hydraulic cylinders shown are taken as an example. When the control system is working, each electro-hydraulic servo valve forms a closed loop control loop with the corresponding hydraulic cylinder and the hydraulic cylinder position detection module. The A/D input module 51 collects the actual position of the hydraulic cylinder detected by the hydraulic cylinder position detection module and inputs it to the PLC controller 52. The PLC controller 52 uses it as a feedback value and performs PID calculations with the set value of the hydraulic cylinder. The calculation result passes D The /A output module 53 outputs to the electro-hydraulic servo amplifier board 54, and after amplifying, it is sent to the electro-hydraulic servo valves 561, 562, 563, and 564. The electro-hydraulic servo valves 561, 562, 563, and 564 drive their respective spools to move. , Thereby controlling the lifting speed and position following of the hydraulic cylinders 61, 62, 63, 64. When performing synchronous control, the PLC controller 52 takes the average value of the actual position values ​​of the four hydraulic cylinders as the adjustment reference. The actual position value of each hydraulic cylinder is subtracted from the average value, and then multiplied by the synchronization coefficient of the hydraulic cylinder. After the result value is normalized, the output of the corresponding electro-hydraulic servo valve is controlled by limiting to coordinate the lifting speed of the four hydraulic cylinders. In this way, the four hydraulic cylinders each form a closed-loop control loop, and the four hydraulic cylinders mutually restrict each other. When the actual position value of any hydraulic cylinder is greater than the average position detection value, the control system automatically reduces its D/ A output, similarly, when the actual position value of any hydraulic cylinder is less than the average value, the system automatically increases its ascent speed, so as to maintain the speed and position synchronization of the four hydraulic cylinders. Among them, the synchronization coefficient can adjust the synchronization accuracy and response speed.

[0057] It should be noted that the number of hydraulic cylinders in the present invention is not limited to four, and can be adjusted according to actual needs. Similarly, the number of control valves is not limited to four, and the number of control valves is only The number of hydraulic cylinders should be equal.

[0058] Of course, the present invention can also have various other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding All changes and deformations shall belong to the protection scope of the appended claims of the present invention.