Control method for reducing roller consumption of S roller set

Abstract

The invention discloses a control method for reducing roller consumption of an S roller group, which comprises the following steps of: correcting the speed of a slave roller on the S roller group through a load balancer, so that the speed of the slave roller is consistent with the speed of a master roller on the S roller group; and the load balancer takes the torque of the driving roller as a reference value, the reference value is compared with an actual value of the torque of the driven roller, a speed correction value of the driven roller is obtained, and the speed correction value limits the speed of the driven roller in a speed window of the load balancer. According to the invention, load distribution of the S roller group is solved, and the speed stability of the S roller group is ensured when abnormal conditions such as slipping occur.

Description

Technical Field

[0001] The invention relates to a roller table technology for a 2050 hot rolling finishing mill, and more specifically to a control method for reducing roller consumption of an S roller group. Background Art

[0002] The existing 2050 hot rolling intensive heat treatment lines of steel enterprises are generally equipped with 4 sets of S rolls. The load balance of the S rolls generally adopts a mode of superimposing the speed integral of the main roll after the blocking speed integral of the slave roll. This control mode is widely used in cold rolling lines.

[0003] However, in the hot rolling finishing unit, due to the poor wrapping of the strip and the S-roll, and when the incoming material is not well deformed, the slave roll is prone to slip. When the above mode is adopted, when the slave roll slips, because it cannot reflect its own velocity integral component, the slave roll speed will oscillate and affect the speed stability of the main roll.

[0004] At present, when the transmission slips, the integral component of the speed regulator of the slave motor is invalid, and the integral component of the master motor is used as torque compensation. At this time, due to the slip of the slave motor, the integral component of the master motor cannot reflect the actual static error of the slave motor. Therefore, the slave motor will fluctuate up and down due to the effect of the proportional Kp value of its own speed regulator. (Special note: The static error is also called the residual error, which refers to the residual deviation in the transition process, that is, the difference between the stable value of the controlled variable and the given value. Its value can be positive or negative. It is an important indicator of accuracy. In production, the static error of the controlled variable is required to be limited to the range near the given value). Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present invention is to provide a control method for reducing the roller consumption of the S roller group, solve the load distribution of the S roller group, and ensure the speed stability of the S roller group when abnormalities such as slipping occur.

[0006] To achieve the above object, the present invention adopts the following technical solution:

[0007] A control method for reducing the roller consumption of the S roller group:

[0008] Correcting the speed of the slave roller on the S roller group by a load balancer so that the speed of the slave roller is consistent with the speed of the master roller on the S roller group;

[0009] The load balancer uses the torque of the master roller as a reference value, and compares it with the actual value of the torque of the slave roller to obtain a speed correction value of the slave roller, and the speed correction value limits the speed of the slave roller within the speed window of the load balancer.

[0010] Preferably, the load balancer adopts a proportional control method.

[0011] Preferably, the input of the proportional control method of the load balancer is the actual torque of the master roller and the actual torque of the slave roller, and the output is the speed correction value of the slave roller.

[0012] Preferably, when the speed main setting of the slave roller + the speed correction value of the slave roller is greater than the actual speed value of the slave roller, the output of the slave roller = (torque setting - torque feedback) * proportional coefficient;

[0013] Otherwise, the output of the slave roller maintains the current value.

[0014] The present invention provides a control method for reducing the roller consumption of an S roller group, solves the load distribution of the S roller group, and ensures the speed stability of the S roller group when anomalies such as slippage occur.

[0015] When slippage also occurs in the control method of the present invention, the slave motor still adjusts its speed by itself. Although the slave motor cannot control the torque of the slave motor to the same torque value as the main motor through the speed additional compensation regulator due to slippage, the slave motor will maintain a relatively uniform speed under the action of the speed window because of the effect of the speed window.

[0016] When slipping, both the traditional solution and the new solution cannot make the slave motor have the same output as the main motor (that is, the torque output remains consistent). This is because slipping is an abnormal condition of load fluctuation. However, when this abnormal condition occurs in the traditional solution, the speed of the slave motor will fluctuate, while the technical solution of this patent application will make the speed of the slave motor more stable. Slipping can lead to practical problems such as increased wear on the surface of the pinch roller and scratches on the surface of the strip, which cannot be avoided. Therefore, slipping must be eliminated and prevented.

[0017] It should be noted that: in an ideal state without slipping, the effects of the above two solutions are the same. Therefore, the purpose of the technology applied in the present invention is only to eliminate or slow down the occurrence of slipping. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the principle of the control method of the present invention;

[0019] Figure 2 It is a control schematic diagram of the control method of the present invention. DETAILED DESCRIPTION

[0020] In order to better understand the above technical solution of the present invention, the technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] Combination Figure 1 , Figure 2 As shown, the present invention provides a multi-motor driven straightening machine load distribution control method:

[0022] The speed of the slave roller 2 on the S roller group is corrected by the load balancer 1 so that the speed of the slave roller 2 is consistent with the speed of the main roller 3 on the S roller group.

[0023] The load balancer 1 uses the torque of the main roller 3 as a reference value, and compares it with the actual value of the torque of the slave roller 2 to obtain the speed correction value of the slave roller 2. The speed correction value limits the speed of the slave roller 2 within the speed window of the load balancer 1. When the S roller group slips, due to the limitation of the speed window, the slave roller 2 will be limited by the speed window to maintain the limited speed. In this way, even if the S roller group has slipped at that time, the speed of the slave roller 2 is still a stable speed without fluctuations, and will not affect the speed of the main roller 3.

[0024] The load balancer 1 adopts proportional control, because if proportional integral control is adopted, only static error can be eliminated. The output of the load balancer 1 in the present invention is given to the transmission device of the slave roller 2 as the speed added value of the slave roller 2, and the transmission device of the slave roller 2 already has an integral link before the speed adjustment. Therefore, the load balancer 1 in the present invention only needs to adopt proportional control to improve the response.

[0025] The inputs of the proportional control mode of the load balancer 1 are the actual torque of the main roller 3 (as the torque reference value of the slave roller 2), the actual torque of the slave roller 2 (as the actual torque feedback of the slave roller 2), the speed window (used to define the upper and lower limit windows of the speed additional value of the slave roller 2), the KP value (the amplification factor of the load balancer 1, used to control the response of the load balancer 1), and the load distribution ratio. The output is the speed correction value of the slave roller 2. The PLC sends this speed additional value to the slave roller 2 as a correction to the given speed.

[0026] When the speed master setting of the slave roller 2 + the speed correction value of the slave roller 2 is greater than the actual speed value of the slave roller 2, the output of the slave roller 2 = (torque setting - torque feedback) * proportional coefficient;

[0027] Otherwise, the output from roller 2 remains at the current value.

[0028] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A control method for reducing the roller consumption of an S roller group, characterized in that: By setting a load balancer in the PLC of the L1 system to correct the speed of the slave roller on the S roller group, the speed of the slave roller is kept consistent with the speed of the master roller on the S roller group; The load balancer uses the torque of the master roller as a reference value, and compares it with the actual value of the torque of the slave roller to obtain a speed correction value of the slave roller, and the speed correction value limits the speed of the slave roller within the speed window of the load balancer.

2. The control method for reducing the roller wear of the S roller group according to claim 1, characterized in that: The load balancer adopts a proportional control method.

3. The control method for reducing the roller wear of the S roller group according to claim 2 is characterized in that: The input of the proportional control method of the load balancer is the actual torque of the master roller and the actual torque of the slave roller, and the output is the speed correction value of the slave roller.

4. The control method for reducing the roller wear of the S roller group according to claim 3 is characterized in that: When the speed master setting of the slave roller + the speed correction value of the slave roller is greater than the actual speed value of the slave roller, the output of the slave roller = (torque setting - torque feedback) * proportional coefficient; Otherwise, the output of the slave roller maintains the current value.

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