Product particle size control method, device, apparatus, and medium

Abstract

The application provides a product particle size control method, device, equipment and medium. The method comprises the following steps: obtaining a first content value corresponding to a first extrusion roller frequency of a roller mill based on a preset fitting relationship between the content of the product particle size and the extrusion roller frequency; processing the first content value and a target content value of the product particle size based on a predictive control model to obtain a target frequency change amount for adjusting the extrusion roller frequency; and adjusting the extrusion roller frequency of the roller mill based on the first extrusion roller frequency and the target frequency change amount. The method of the application is efficient and automatically controls the product particle size without manual intervention.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of roll mill control, and particularly relates to a product particle size control method, device, equipment and medium. BACKGROUND

[0002] The roll mill completes the crushing process of ore particles through the opposite rotation of the dynamic roller and the fixed roller based on the laminated crushing principle. The roll mill generally measures the crushing effect by the content of product particle size. Improving the crushing effect of the roll mill can effectively improve the screening efficiency of the subsequent inspection screening process, and is conducive to the stable operation of the inspection screen.

[0003] In some schemes, the optimization processing of the product particle size of the roll mill is mostly controlled by manual control, such as observing the undersize ore of the inspection screen, and then adjusting the work parameters such as the roll mill feed bin level and the roll mill roller speed according to the work experience. The adjustment method of the product particle size is relatively extensive, too dependent on manual experience, high in cost and low in efficiency. SUMMARY

[0004] The present application provides a product particle size control method, device, equipment and medium to solve the problem of high cost and low efficiency of product particle size adjustment.

[0005] In one aspect, the present application provides a product particle size control method applied to a control device of a roll mill system, wherein the roll mill system comprises a roll mill. The method comprises: obtaining a first content value corresponding to a first extrusion roller frequency of the roll mill based on a preset fitting relationship between the content of the product particle size and the extrusion roller frequency; processing the first content value and a target content value of the product particle size based on a predictive control model to obtain a target frequency change amount for adjusting the extrusion roller frequency; and adjusting the extrusion roller frequency of the roll mill based on the first extrusion roller frequency and the target frequency change amount.

[0006] In an implementation, the processing of the first content value and the target content value of the product particle size by the predictive control model to obtain a target frequency change amount for adjusting the frequency of the extrusion roller includes: constructing an optimization function among the content of the product particle size, the target content value and the frequency change amount based on the predictive control model; inputting the first content value and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount; if the unit frequency change amount is greater than a preset frequency adjustment threshold, taking the unit frequency change amount as the target frequency change amount; if the unit frequency change amount is less than the preset frequency adjustment threshold, repeatedly performing the steps of updating the first extrusion roller frequency based on the sum of the unit frequency change amount and the first extrusion roller frequency, obtaining the first content value corresponding to the updated first extrusion roller frequency, inputting the first content value corresponding to the updated first extrusion roller frequency and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount, until the sum of all unit frequency change amounts is greater than the preset frequency adjustment threshold, and taking the sum of all unit frequency change amounts as the target frequency change amount.

[0007] In an implementation, the optimization function includes:

[0008] minJ = (E t -R) 2 + λ(Δf) 2

[0009] wherein, J is the optimization function, E t is the first content value, R is the target content value, Δf is the unit frequency change amount, λ is the weight factor, and t is the time t.

[0010] In an implementation, before the preset fitting relationship between the content of the product particle size and the frequency of the extrusion roller is obtained, the method further includes: obtaining a historical extrusion roller frequency of the roller mill; obtaining a historical content of the product particle size output by the roller mill after a preset time length; wherein, the preset time length represents a response time length between the change of the extrusion roller frequency of the roller mill and the content of the product particle size; and performing numerical fitting based on the historical extrusion roller frequency and the historical content to obtain the preset fitting relationship.

[0011] In an implementation, the adjusting the frequency of the compression roller of the roller mill based on the first frequency of the compression roller and the target frequency variation includes: adding the first frequency of the compression roller and the target frequency variation to obtain an initial adjustment frequency; detecting a relationship between the initial adjustment frequency and a preset adjustment frequency range to obtain a relationship result; if the relationship result indicates that the initial adjustment frequency is within the preset adjustment frequency range, adjusting the frequency of the compression roller based on the initial adjustment frequency; and if the relationship result indicates that the value of the initial adjustment frequency is not within the values of the preset adjustment frequency range, adjusting the frequency of the compression roller based on an extreme value in the preset adjustment frequency range.

[0012] In an implementation, the roller mill system further includes a feeder, a feed belt, and a feed bin, the product to be roller milled in the feeder enters the feed bin from the feed belt and enters the roller mill through the feed bin; before the preset fitting relationship between the content of the product particle size and the frequency of the compression roller is used to obtain the first content value corresponding to the first frequency of the compression roller, the method further includes: obtaining a target belt content of the feed belt, performing proportional-integral control on the frequency of the feeder based on the target belt content to control the amount of the product to be roller milled entering the roller mill; and / or, obtaining a target content of the feed bin, performing proportional-integral control on the frequency of the feed belt based on the target content to control the amount of the product to be roller milled entering the roller mill.

[0013] In an implementation, the preset fitting relationship between the content of the product particle size and the frequency of the compression roller is used to obtain the first content value corresponding to the first frequency of the compression roller, including: obtaining an initial content value corresponding to the first frequency of the compression roller based on the preset fitting relationship; correcting the initial content value based on proportional-integral control to obtain the first content value.

[0014] In a second aspect, the application provides a product particle size control device, including: a control device applied to a roller mill system, the roller mill system including a roller mill, the device including: a content value prediction module configured to obtain a first content value corresponding to a first frequency of a compression roller of the roller mill based on a preset fitting relationship between a content of a product particle size and a frequency of the compression roller; a frequency variation measurement module configured to process the first content value and a target content value of the product particle size based on a prediction control model to obtain a target frequency variation for adjusting the frequency of the compression roller; and a frequency adjustment module configured to adjust the frequency of the compression roller of the roller mill based on the first frequency of the compression roller and the target frequency variation.

[0015] Thirdly, this application provides an electronic device, which includes: a processor and a memory; the memory is used to store instructions; the processor is used to execute the instructions in the memory, causing the electronic device to perform the product-level control method as described in the first aspect.

[0016] Fourthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the product-level control method as described in the first aspect.

[0017] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the product-level control method as described in the first aspect.

[0018] The product particle size control method, device, equipment, and medium provided in this application use a preset fitting relationship to determine the product particle size content corresponding to the extrusion roller frequency. By using the fitted content value and the target content value, a value for adjusting the roller mill frequency is obtained. The roller mill is then adjusted using this frequency. This process is automated and requires no manual intervention, enabling low-cost and efficient control of product particle size. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0020] Figure 1 A flowchart illustrating the operation of a roller mill system as an exemplary embodiment;

[0021] Figure 2 A schematic diagram of the structure of a roller mill system shown in an exemplary embodiment;

[0022] Figure 3 A flowchart illustrating a product-level control method as an exemplary embodiment;

[0023] Figure 4 A flowchart illustrating another product-level control method as an exemplary embodiment;

[0024] Figure 5 A flowchart illustrating another product-level control method as an exemplary embodiment;

[0025] Figure 6 A flowchart illustrating another product-level control method as an exemplary embodiment;

[0026] Figure 7 A flowchart illustrating another product-level control method as an exemplary embodiment;

[0027] Figure 8 A product size control device structure diagram is shown for an exemplary embodiment.

[0028] Figure 9 A block diagram of an electronic device is shown for an exemplary embodiment.

[0029] The specific embodiments of the application have been shown by way of example in the drawings and will be described in greater detail in the following. These drawings and description are not meant to restrict the scope of the inventive concept in any way but to illustrate only the inventive concept for the person skilled in the art by way of reference to specific embodiments. DETAILED DESCRIPTION

[0030] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The description of the exemplary embodiments is intended to apply to any embodiment of the application, unless specified otherwise. Although the following description is made with respect to the exemplary embodiments, it is to be understood that many variations are possible and changes can be made as would be obvious to one skilled in the art without departing from the spirit and scope of this application which is to be limited only by the appended claims and their equivalents.

[0031] The roller mill is based on the principle of laminated crushing, and the crushing process of ore particles is completed by the opposite rotation of the fixed roller and the movable roller. The ore particles are fed from above the two rollers, and move downward with the rotation of the fixed roller and the movable roller. After laminated crushing, the ore particles become dense cakes which are discharged from the mill. The discharged products contain a large amount of fine and micro-fine particles, and rich micro-cracks are generated inside the coarse particles, which is beneficial to the liberation of ore particles during grinding, improves the processing capacity of the mill, and is beneficial to multi-crushing and less grinding.

[0032] In order to make the roller mill work at its maximum efficiency and avoid large pieces of material entering the ball mill process, the roller mill system is mostly closed-circuit operation with inspection screening. The operation flow chart of the roller mill system can be referred to Figure 1 The ore is stored in the storage bin, and the ore in the storage bin is fed into the ore feeding belt by the feeder. The ore in the ore feeding belt is conveyed to the feeding bin, and the ore in the feeding bin is crushed by the roller mill. The discharged products are all conveyed to the inspection screen by the transfer belt, and the material on the screen can be returned to the roller mill by the running belt for re-crushing. The products under the screen are fed into the subsequent grinding process. Improving the crushing effect of the roller mill can effectively improve the screening efficiency of the subsequent inspection screening process, and is beneficial to the stable operation of the inspection screen.

[0033] At present, most high-pressure roller mills measure the crushing effect of the roller mill mainly by the content of the particle size in the product, such as the content of the particle size of-3mm (millimeter), and the roller speed of the roller mill has a certain influence on the content of the particle size in the discharged product of the roller mill, that is, within a certain range, increasing the roller speed can increase the crushing ratio of the roller mill, make the particle size of the product finer, and increase the content of the target particle size in the discharged product. Based on this, reasonable control of the roller speed of the high-pressure roller mill can optimize the crushing effect of the high-pressure roller mill, increase the content of the particle size in the product, and reduce the energy consumption of the high-pressure roller mill system.

[0034] Meanwhile, in actual production, the feeding of the roller mill is affected by the change of the properties of the fed ore, and under the condition that the roller gap remains unchanged, the flow capacity of the ore in the equipment will inevitably change, thereby causing the change of the material level of the feeding bin. When the material level of the feeding bin is too low, the crushing effect of the material layer of the roller mill will be affected, and when the material level is particularly low, no cushion layer is formed, the time for the new feeding to be crushed in the roller mill is reduced, the particle size of the discharged product will be obviously coarse, and the working efficiency of the equipment is reduced. On the contrary, when the material level of the feeding bin is too high, the ore will overflow the feeding hopper, and passive shutdown is required. On the other hand, affected by the abnormal upstream production process, equipment failure, etc., the feeding machine of the roller mill may also fail to feed in time, at this time, the feeding control system of the roller mill should also be handled accordingly to prevent the equipment from running for a long time under no load. Therefore, in order to improve the crushing effect of the roller mill, it is necessary to ensure the stable control of the feeding amount of the roller mill, that is, the stable material level of the feeding bin of the roller mill.

[0035] In some schemes, the optimization of the product particle size of the roller mill is mainly controlled by manual control, the undersize ore amount of the screen is observed and checked by manual observation, and the adjustment of the material level of the feeding bin of the roller mill and the roller speed of the roller mill is made according to the working experience. The adjustment mode of the product particle size of the roller mill is relatively extensive and too dependent on manual experience.

[0036] The product particle size control method provided in the present application aims to solve the problem that the adjustment of the particle size content of the roller mill is mainly determined by manual and experience, and the efficiency is low.

[0037] The technical solutions of the present application and how the technical solutions of the present application solve the above technical problems will be described in detail in specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of the present application will be described below with reference to the drawings.

[0038] It should be noted that, Figure 1 The operation process of the roller mill system in the figure is exemplary to show the structure of some roller mills, and there are other structures Figure 1 which are not shown in the figure, such as Figure 2 As can be understood,Figure 2 The roll mill system in the figure is controlled by the control device when performing the corresponding process. Specifically, the control device can control the frequency of the feeder in the roll mill system, thereby controlling the amount of ore entering the ore feeding belt. The control device can also control the frequency of the ore feeding belt, thereby controlling the amount of ore on the ore feeding belt and the amount of ore entering the feeding bin. The control device can also control the frequency of the roll mill to roll the ore in the roll mill. Of course, the control device can also control the frequency of the transfer belt and the running belt, thereby controlling the amount of product entering the inspection screen and the amount of product entering the ore feeding belt, respectively.

[0039] Of course, the roll mill system can also include a data acquisition device to acquire data of the structures in the roll mill system when in operation, such as the motor frequency of the movable roll and the fixed roll of the roll mill, the amount of ore on the ore feeding belt, the level of the feeding bin, and the product particle size. The acquisition device can be connected to the control device, thereby inputting the data to the control device, so that the control device controls and processes the relevant devices in the roll mill system based on the data.

[0040] Of course, in some embodiments, the data obtained by the acquisition device will be preprocessed after entering the control device, such as preprocessing the collected data by the moving average method to eliminate noise in the data.

[0041] The product particle size control method in this embodiment can be used in a roll mill system, and is particularly applied to a control device in the roll mill system. The control device processes the data collected by the data acquisition device, thereby adjusting the frequency of the roll mill in the roll mill system, controlling the roll speed in the roll mill, and adjusting the particle size content of the product output by the roll mill, thereby improving the efficiency of the roll mill.

[0042] Figure 3 is a product particle size control method flowchart shown by an exemplary embodiment, applied to a control device of a roll mill system, which includes a roll mill, such as Figure 3 The method includes steps S310 to S350, which are explained in detail as follows:

[0043] Step S310: Based on the preset fitting relationship between the content of the product particle size and the frequency of the extrusion roll, a first content value corresponding to a first frequency of the extrusion roll of the roll mill is obtained.

[0044] In this embodiment, the collecting device collects the first extrusion roller frequency of the roller mill, which is essentially the motor frequency of the extrusion roller of the roller mill. The extrusion roller includes a movable roller and a fixed roller. The change of the extrusion roller frequency can change the speed of the extrusion roller. The product particle size content is the product particle size content of the product obtained after the roller mill processing. In this embodiment, the product can be regarded as the ore obtained after the roller mill processing, and the product to be rolled is the ore that needs to be processed in the roller mill.

[0045] In this embodiment, the preset fitting relationship can be obtained by fitting calculation based on the historical product particle size content and the extrusion roller frequency corresponding to the product particle size content. For example, a relationship formula can be first set, in which the product particle size content is the dependent variable and the extrusion roller frequency is the independent variable. Then, the product particle size content and the extrusion roller frequency corresponding to the product particle size content in the historical data are input into the relationship formula for fitting. Thus, the preset fitting relationship can be obtained. The relationship formula can be a linear function, a nonlinear function, or a machine model, which is not limited here.

[0046] For example, in some embodiments, the relationship formula is a linear function:

[0047] E(f) = a + bf

[0048] wherein E(f) is the product particle size content, f is the extrusion roller frequency, and a and b are parameters. After fitting the relationship formula, the specific values of a and b can be obtained. Thus, the specific values of a and b can be brought into the relationship formula to obtain the preset fitting relationship.

[0049] In some embodiments, the first extrusion roller frequency is input into the preset fitting relationship to obtain the first content value, which can be regarded as the particle size content value of the product output by the current extrusion roller.

[0050] It can be understood that, in the actual process, when the extrusion roller frequency changes, the product particle size content detected at the detection screen will not immediately change to the content value corresponding to the frequency, but there is a certain hysteresis. The hysteresis time can be set as a preset time length. That is, the product particle size content corresponding to the extrusion roller frequency measured at time t should be detected at time t + preset time length, not the product particle size content detected at time t. Therefore, the preset time length corresponds to the value m. The first content value corresponding to the first extrusion roller frequency at time t is the first content value at time t + m. For time t + 1, the first content value corresponding to the first extrusion roller frequency at time t + 1 is the first content value at time t + 1 + m.

[0051] The first extrusion roller frequency can be the real-time measured frequency value, such as the first extrusion roller frequency measured at time t, which is set as ft , then the corresponding first content value is E t As can be seen above, E t The subscript t of E t corresponds to the time when the first extrusion roller frequency is obtained, and E t is the content value measured by the detection screen after the extrusion roller frequency is adjusted to f t , and after a preset time m.

[0052] In some embodiments, since the preset fitting relationship obtained by fitting may have errors, the content value obtained by fitting the first extrusion roller frequency can also be corrected, that is, the particle size content value obtained by inputting into the preset fitting relationship is taken as the initial content value, and then the initial content value is corrected based on proportional integral control to obtain the first content value. In some embodiments, the step S310 can include S10 to S12:

[0053] S10: obtaining the initial content value corresponding to the first extrusion roller frequency based on the preset fitting relationship.

[0054] S12: correcting the initial content value based on proportional integral control to obtain the first content value.

[0055] The initial content value is the particle size content value obtained by inputting the first extrusion roller frequency into the preset fitting relationship.

[0056] In some embodiments, the proportional integral control can be realized by the following formula:

[0057] m t = K p * Δe t + K i ∫0 t Δe t dt

[0058] E t = m t + E(f)

[0059] Wherein, m t is a correction coefficient, K p , K i are proportional and integral gain coefficients, Δe t is the error between the initial content value and the first content value, E t is the first content value, E(f) is the initial content value, and t is the time t.

[0060] It should be noted that since there is a preset time lag between the extrusion roller frequency and the content value of the product particle size, E t is essentially the first content value corresponding to the first extrusion roller frequency at time t, that is, the first content value measured at time t+m.

[0061] Of course, the first content value E t The subscript t corresponds to the first content value corresponding to the first extrusion roller frequency detected at time t, and is not the first content value actually detected at time t, which actually corresponds to the product particle size content value detected at time t+m, when the subscript of the first content value is other numerical value, the corresponding first content value is the first content value corresponding to the first extrusion roller frequency detected at the time corresponding to the other numerical value, such as when there is a first content value E t+4 , which means the first content value corresponding to the first extrusion roller frequency of the roller mill at time t+4, that is, the content value of the product particle size measured at time t+4+m.

[0062] It can be understood that the preset fitting relationship in the embodiment is related to the product particle size, that is, the preset fitting relationship between the content of the corresponding product particle size and the extrusion roller frequency may be different or the same for different product particle sizes.

[0063] For example, if the product particle size is -3mm, the historical -3mm product particle size content and extrusion roller frequency data are fitted to obtain the preset fitting relationship between the -3mm product particle size content and the extrusion roller frequency, and if the product particle size is -5mm, the historical -5mm product particle size content and extrusion roller frequency data are fitted to obtain the preset fitting relationship between the -5mm product particle size content and the extrusion roller frequency. In actual use, the corresponding preset fitting relationship is determined according to the determined product particle size used as the evaluation index of the crushing effect of the roller mill, such as the -3mm product particle size content as the evaluation index of the crushing effect of the roller mill, and the corresponding preset fitting relationship is obtained by calculating the -3mm product particle size content and the extrusion roller frequency.

[0064] It should be noted that the preset adjustment frequency range exists in the influence of the extrusion roller frequency on the characteristics of the product particle size, that is, within the preset adjustment frequency range, the adjustment of the frequency has a certain relationship with the content of the product particle size of the roller mill, and beyond the preset adjustment frequency range, the adjustment of the extrusion roller frequency has little effect on the content of the product particle size of the roller mill. Therefore, in order to ensure the effectiveness of the control, the preset adjustment frequency range is determined to be between fmin and fmax, that is, the extrusion roller frequency in the preset fitting relationship is within the range of fmin to fmax, which can be fmin or fmax.

[0065] The preset adjustment frequency range in the embodiment can be determined according to a relational expression of a preset fitting relationship, and can also be obtained through an empirical parameter. For example, the frequency of the extrusion roller can be adjusted, and a value at which the adjustment of the frequency of the extrusion roller has a smaller influence on the content of the product particle size is found, which is used as an extreme value of the preset adjustment frequency range. Alternatively, when the frequency of the extrusion roller is adjusted, a value at which the content of the product particle size changes by less than a certain value is used as an extreme value of the preset adjustment frequency range. Similarly, the determination of the effective range is also related to the product particle size. For example, the effective ranges of the -3 mm product particle size and the -5 mm product particle size are different. That is, the setting of the preset adjustment frequency range is related to the relational expression and the product particle size.

[0066] Step S330: The first content value and the target content value of the product particle size are processed based on the predictive control model to obtain a target frequency change amount for adjusting the frequency of the extrusion roller.

[0067] In the embodiment, the optimization control of the product particle size of the roller mill is performed based on the predictive control model. Specifically, an optimization function between the content of the product particle size and the frequency of the extrusion roller is constructed based on the predictive control model. Through iterative optimization of the optimization function, an optimal frequency adjustment amount that causes the content of the product particle size to approach the target content of the product particle size is found. The current state is used as an input to predict the change amount of the future control signal, thereby improving the stability of the control system and having the advantages of pre-adjustment and fast dynamic response speed of system adjustment. The prediction variable of the optimization function is the content of the product particle size, and the final output control signal is the frequency change of the motor of the movable roller and the fixed roller, that is, the target frequency change amount of the extrusion roller. Generally, the frequency of the movable roller and the frequency of the fixed roller are synchronously adjusted, and the adjustment amounts are consistent, so as to ensure the stability of the crushing process of the roller mill.

[0068] Specifically, in the embodiment, the first content value can be input to the optimization function, and the target content value can be input to the optimization function. The target frequency change amount can be obtained. The target frequency change amount can be regarded as a value obtained by adjusting the current frequency of the extrusion roller based on the frequency change amount, so that the content of the product particle size output by the product approaches the target content value.

[0069] Step S350: The frequency of the extrusion roller of the roller mill is adjusted based on the first frequency of the extrusion roller and the target frequency change amount.

[0070] In the embodiment, the first frequency of the extrusion roller is added to the frequency change amount, and a value for adjusting the frequency of the extrusion roller is obtained.

[0071] In some embodiments, since the frequency of the extrusion roller has a preset adjustment frequency range, the obtained value for adjusting the frequency of the extrusion roller is compared with the preset adjustment frequency range, so as to finally determine the value for adjusting the frequency of the extrusion roller. That is, the step S350 can include S20 to S23.

[0072] S20: add the first extrusion roller frequency and the target frequency variation to obtain an initial adjustment frequency.

[0073] S21: detect the relationship between the initial adjustment frequency and the preset adjustment frequency range to obtain a relationship result.

[0074] S22: if the relationship result indicates that the initial adjustment frequency is located in the preset adjustment frequency range, adjust the extrusion roller frequency based on the initial adjustment frequency.

[0075] S23: if the relationship result indicates that the value of the initial adjustment frequency is not located in the value of the preset adjustment frequency range, adjust the extrusion roller frequency based on the extreme value in the preset adjustment frequency range.

[0076] In this embodiment, the relationship result indicates that the initial adjustment frequency is not located in the preset adjustment frequency range, and the size of the initial adjustment frequency and all values of the preset adjustment frequency range is detected, if the initial adjustment frequency is greater than the preset adjustment frequency range, the extreme value is the maximum value in the preset adjustment frequency range, and if the initial adjustment frequency is less than the preset adjustment frequency range, the extreme value is the minimum value in the preset adjustment frequency range.

[0077] In this embodiment, the relationship between the frequency and the product particle size content is obtained by numerical fitting, the content value corresponding to the current frequency is determined, and the numerical value of the adjustment roller mill frequency is obtained by predicting the fitted content value and the target content value, so that the product particle size content obtained by adjusting the roller mill through the frequency is close to or is the target particle size content; the product particle size control method proposed in this embodiment does not require manual participation, is automatically completed, and is efficient.

[0078] Figure 4 is another product particle size control method shown in an example embodiment, Figure 4 shown in Figure 3 An implementation of step S330 in Figure 4 The method includes steps S410 to S470, which are explained in detail as follows:

[0079] Step S410: based on the predictive control model, an optimization function is constructed between the content of the product particle size, the target content value and the frequency variation.

[0080] In this embodiment, the prediction variable of the optimization function is the content of the product particle size, and the output is the variation of the extrusion roller frequency. By constructing the optimization function through the content of the product particle size and the variation of the extrusion roller frequency, the final variation of the extrusion roller frequency can be obtained by iteration.

[0081] In some embodiments, the optimization function is obtained based on the predictive control model, wherein the optimization function includes the content of the product particle size, i.e. the content of the product particle size at a certain time, a target content value, and a frequency change amount, which can be the change amount of the extrusion roller frequency between the previous time and the next time.

[0082] Step S430: inputting the first content value and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount.

[0083] In some embodiments, the optimization function includes:

[0084] minJ = (E t -R) 2 +λ(Δf) 2

[0085] wherein J is the optimization, E t is the first content value, R is the target content value, Δf is the unit frequency change amount, and λ is a weight factor.

[0086] Of course, the above optimization function is only exemplary, and in other embodiments, other representative optimization functions can also be used, which are not specifically limited here.

[0087] In the present embodiment, the unit frequency change amount can be obtained through the optimization function, which is essentially the difference between the predicted next time extrusion roller frequency and the first extrusion roller frequency, so that the next time extrusion roller frequency, i.e. the t+1 time extrusion roller frequency, can be obtained. t+1 .

[0088] Step S450: if the unit frequency change amount is greater than a preset frequency adjustment threshold, the unit frequency change amount is taken as the target frequency change amount.

[0089] In the present embodiment, frequent adjustment of the extrusion roller frequency can cause damage to the motor of the movable roller and the fixed roller, so a preset frequency adjustment threshold α is set for the frequency change amount of the extrusion roller motor, and the change amount of the frequency needs to be greater than α to cause the change of the extrusion roller frequency.

[0090] If the unit frequency change amount obtained in step S430 is greater than the preset frequency adjustment threshold, the unit frequency change amount is taken as the target frequency change amount, otherwise, iteration update is still needed to predict the unit frequency change amount of the next time, i.e. the unit frequency change amount between f t+2 and f t+1 .

[0091] Step S470: If the unit frequency variation is less than the preset frequency adjustment threshold, then the step of updating the first extrusion roller frequency based on the sum of the unit frequency variation and the first extrusion roller frequency, and obtaining the first content value corresponding to the updated first extrusion roller frequency is repeatedly performed until the sum of all the unit frequency variations obtained is greater than the preset frequency adjustment threshold, so as to take the sum of the unit frequency variations obtained as the frequency variation.

[0092] In the embodiment, the unit frequency variation is less than the preset frequency adjustment threshold, at this time, the extrusion roller frequency is not adjusted, and the unit frequency variation at the subsequent moment is calculated until the sum of the unit frequency variations obtained is greater than the preset frequency adjustment threshold, then the calculation of the unit frequency variation is stopped, and the sum of the unit frequency variations obtained is taken as the target frequency variation.

[0093] Specifically, after obtaining f t+1 , f t+1 is taken as the new first extrusion roller frequency, then the first content value corresponding to the new first extrusion roller frequency is calculated based on the preset fitting relationship, and the new first content value is input into the optimization function to obtain a new unit frequency variation, at this time, two frequency variations are obtained, the new unit frequency variation is actually the frequency variation at the next moment corresponding to the moment of the previous unit frequency variation, that is, if the first unit frequency variation is the frequency variation at the moments of t and t-1, then the new unit frequency variation is the frequency variation at the moments of t+1 and t, at this time, the values of the two unit frequency variations are added to determine whether the obtained value is greater than the preset frequency adjustment threshold, if yes, then the added value is taken as the target frequency variation, if no, then the frequency at the next moment is obtained based on the newly obtained unit frequency variation and the new first extrusion roller frequency, that is, the new f t+1 is obtained, the above operation is repeated to obtain multiple unit frequency variations until the sum of the unit frequency variations obtained is greater than the preset frequency adjustment threshold, and the calculation of the new unit frequency variation is stopped.

[0094] In some embodiments, the optimization function can also be:

[0095] minJ = (E t+d -R) 2 + λ (f t+1+d -f t+d ) 2

[0096] Wherein, the range of d is a positive integer including 0, t+d is at the moment of t+d, when d is 0, E t is f ta corresponding first content value, f t+1 is the extrusion roller frequency at time t+1, f t is the first extrusion roller frequency, at this time, the unit frequency change amount Δf t t+1 t , whether Δf t is greater than the preset frequency adjustment threshold, if greater, then Δf t is the target frequency change amount, otherwise, d=1, according to Δf t and f t , f t+1 is calculated t+1 , and E t+1 is solved according to the preset fitting relationship and f t+1 , and Δf t+1 is obtained by bringing E t into the above optimization function. At this time, whether Δf t+1 +Δf t is greater than the preset frequency adjustment threshold, if greater, then Δf t+1 +Δf t is the target frequency change amount, otherwise, d=2, and so on, Δf t+1 , Δf t+d , until, is greater than the preset frequency adjustment threshold, and is taken as the target frequency change amount, and n is a constant.

[0097] Similarly, the content value of the product particle size corresponding to the numerical values E t , E t+1 is the content value corresponding to the first extrusion roller frequency at the time corresponding to the subscript, that is, the actual content value actually measured at times t+m, t+1+m, etc.

[0098] In this embodiment, by predicting the control model, the optimal extrusion roller frequency change amount is optimized, avoiding the problems of control process overshoot, easy to produce roller mill energy consumption increase, motor damage, roller surface wear, etc. caused by the large adjustment range of the extrusion roller frequency existing in the fuzzy control, feedback regulation, gradient regulation and other algorithms, and setting the preset frequency adjustment threshold to avoid the problems of control effect not reaching in time and poor dynamic response effect caused by the small adjustment range of the extrusion roller frequency, thereby improving the efficiency of product particle size control.

[0099] Figure 5 is another product particle size control method shown in an exemplary embodiment, Figure 5 is an implementation of the preset fitting relationship, as shown in Figure 5 , the method comprises steps S510 to S550, which are explained in detail as follows: ​​

[0100] Step S510: Obtain the historical extrusion roller frequency of the roller mill.

[0101] Step S530: After the time corresponding to the preset time length, obtain the historical content of the product particle size of the roller mill output.

[0102] The preset time length represents the response time length between the change of the extrusion roller frequency of the roller mill and the content of the product particle size.

[0103] In this embodiment, the content of the product particle size is generally measured at the detection screen, and the change of the extrusion roller frequency has a lag corresponding to the change of the content of the product particle size, that is, when the extrusion roller frequency changes, the content of the product particle size will not change immediately, but there is a certain lag time, which is the response time length between the change of the frequency and the content of the product particle size.

[0104] Therefore, the historical extrusion roller frequency obtained at time t corresponds to the historical content of the product particle size at time t+m, and m is the preset time length.

[0105] Step S550: Numerical fitting is performed based on the historical extrusion roller frequency and the historical content to obtain a preset fitting relationship.

[0106] At this time, the obtained historical extrusion roller frequency and historical content are in a corresponding relationship, so that numerical fitting can be performed based on the historical extrusion roller frequency and the historical content to obtain a preset fitting relationship.

[0107] In this embodiment, by calculating the response time length, an accurate relationship between the frequency and the content of the product particle size is obtained, thereby improving the accuracy of subsequent product particle size control.

[0108] Figure 6 Another product particle size control method is shown in an example embodiment, Figure 6 The method shown in the embodiment should be implemented for Figure 3 Before step S310 in the embodiment, as shown in the embodiment, Figure 6 The method includes steps S610 to S630, which are explained in detail as follows:

[0109] Step S610: Obtain the target ore belt quantity of the ore feeding belt, and perform proportional integral control on the frequency of the feeder based on the target ore belt quantity to control the amount of product to be roller milled into the roller mill.

[0110] In this embodiment, step S610 and step S630 can be executed together, and at this time, the execution order of step S610 can precede step S630. Of course, in some embodiments, only one of the steps can be executed.

[0111] It should be noted that due to the anti-interference ability of the data acquisition device itself and the impact force generated by the product falling and other factors, the instantaneous ore quantity may frequently fluctuate, therefore, for the ore quantity parameters collected, a moving average method is used to process the average ore quantity of the ore feeding belt in every certain period of time as a monitoring parameter to eliminate the high-frequency noise of the ore feeding belt.

[0112] The product to be roller milled is the ore that needs to enter the roller mill, and the content of the product particle size is the relevant data of the product obtained after the roller mill processing; in some embodiments, after the product in the roller mill is screened by the inspection screen, some of the product is transported to the ore feeding belt by the running belt for roller mill processing again, at this time, the product entering the ore feeding belt through the running belt is also regarded as the product to be roller milled.

[0113] In this embodiment, according to the operating conditions of the roller mill system, the upper and lower threshold values of the ore quantity of the ore feeding belt and the target value of the ore quantity are set, and the frequency of the feeder is controlled by using the PID (proportional integral control) adjustment mode according to the target ore quantity of the ore feeding belt, so as to stabilize the ore quantity of the ore feeding belt and stabilize the accumulation thickness of the product to be roller milled on the ore feeding belt, thereby controlling the amount of the product to be roller milled entering the roller mill.

[0114] Step S630: obtaining the target ore quantity of the feeding bin, and controlling the frequency of the ore feeding belt based on the proportional integral control of the target ore quantity, so as to control the amount of the product to be roller milled entering the roller mill.

[0115] Similarly, the target ore quantity of the feeding bin and the upper and lower threshold values are set, and the frequency of the ore feeding belt is controlled by using the PID adjustment mode according to the target ore quantity of the feeding bin, so as to stabilize the feeding bin level and thereby control the amount of the product to be roller milled entering the roller mill.

[0116] In this embodiment, by adjusting the frequency of the feeder and the frequency of the ore feeding belt, the stability of the roller mill system is ensured, and the efficiency of the subsequent product particle size control is improved.

[0117] Figure 7 Another product particle size control method is shown in an example embodiment, when performing product particle size control, the following steps are included: data acquisition and processing, then controlling the frequency of the feeder and the frequency of the ore feeding belt, determining the preset frequency adjustment threshold value and the preset adjustment frequency range, and obtaining the preset fitting relationship; obtaining the first extrusion roller frequency and the first content value, establishing an optimization function, obtaining the target frequency change amount, calculating the initial adjustment frequency, and if the initial adjustment frequency is within the preset adjustment frequency range, adjusting the extrusion roller frequency by the initial adjustment frequency; if the initial adjustment frequency is greater than the value within the preset adjustment frequency range, adjusting the extrusion roller frequency by the maximum value of the preset adjustment frequency range; and if the initial adjustment frequency is less than the value within the preset adjustment frequency range, adjusting the extrusion roller frequency by the minimum value of the preset adjustment frequency range.

[0118] Figure 8 is a product particle size control device structure diagram shown in an example embodiment, applied to a control device of a roller mill system, the roller mill system including a roller mill, the product particle size control device 800 including: a content value prediction module 810 configured to obtain a first content value corresponding to a first extrusion roller frequency of the roller mill based on a preset fitting relationship between a content of a product particle size and the extrusion roller frequency; a frequency change measurement module 830 configured to process the first content value and a target content value of the product particle size based on a prediction control model to obtain a target frequency change amount for adjusting the extrusion roller frequency; and a frequency adjustment module 850 configured to adjust the extrusion roller frequency of the roller mill based on the first extrusion roller frequency and the target frequency change amount.

[0119] In an implementable manner, the frequency change measurement module 830 includes: an optimization function establishment unit configured to construct an optimization function among the content of the product particle size, the target content value, and the frequency change amount based on the prediction control model; a unit frequency change amount determination unit configured to input the first content value and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount; a first frequency change measurement unit configured to, if the unit frequency change amount is greater than a preset frequency adjustment threshold, take the unit frequency change amount as the target frequency change amount; and a second frequency change measurement unit configured to, if the unit frequency change amount is less than the preset frequency adjustment threshold, repeatedly perform the steps of updating the first extrusion roller frequency based on a sum of the unit frequency change amount and the first extrusion roller frequency, obtaining a first content value corresponding to the updated first extrusion roller frequency, inputting the first content value corresponding to the updated first extrusion roller frequency and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount, until a sum of all obtained unit frequency change amounts is greater than the preset frequency adjustment threshold, and taking the sum of the unit frequency change amounts as the target frequency change amount.

[0120] In an implementable manner, the optimization function in the frequency change measurement module 830 includes:

[0121] minJ=(E t -R) 2 +λ(Δf) 2

[0122] wherein J is the optimization function, E t is the first content value, R is the target content value, Δf is the unit frequency change amount, and λ is a weight factor.

[0123] In an implementation, the product particle size control device 800 further comprises: a historical frequency acquisition module configured to acquire a historical extrusion roller frequency of the roller mill; a historical content acquisition module configured to acquire a historical content of the product particle size output by the roller mill after a preset time length; wherein the preset time length represents a response time length between the change of the extrusion roller frequency of the roller mill and the content of the product particle size; and a preset fitting relationship confirmation module configured to perform numerical fitting based on the historical extrusion roller frequency and the historical content to obtain a preset fitting relationship.

[0124] In an implementation, the frequency adjustment module 850 comprises: an initial adjustment frequency acquisition unit configured to add the first extrusion roller frequency and the target frequency change amount to obtain an initial adjustment frequency; a relationship result determination unit configured to determine a relationship between the initial adjustment frequency and the preset adjustment frequency range to obtain a relationship result; a first adjustment unit configured to, if the relationship result indicates that the initial adjustment frequency is within the preset adjustment frequency range, adjust the extrusion roller frequency based on the initial adjustment frequency; and a second adjustment unit configured to, if the relationship result indicates that the value of the initial adjustment frequency is not within the values of the preset adjustment frequency range, adjust the extrusion roller frequency based on the extreme value in the preset adjustment frequency range.

[0125] In an implementation, the roller mill system further comprises a feeder, a feeding belt and a feeding bin connected in sequence, the product to be roller milled in the feeder enters the feeding bin from the feeding belt and enters the roller mill through the feeding bin; the product particle size control device 800 further comprises: a feeder control module configured to acquire a target belt ore amount of the feeding belt, and perform proportional integral control on the frequency of the feeder based on the target belt ore amount to control the amount of the product to be roller milled entering the roller mill; and / or a feeding belt control module configured to acquire a target ore amount of the feeding bin, and perform proportional integral control on the frequency of the feeding belt based on the target ore amount to control the amount of the product to be roller milled entering the roller mill.

[0126] In an implementation, the content value prediction module 810 comprises: an initial content value acquisition unit configured to acquire an initial content value corresponding to the first extrusion roller frequency based on the preset fitting relationship; and a content value correction unit configured to correct the initial content value based on the proportional integral control to obtain the first content value.

[0127] The product particle size control device provided by the embodiment can be used to execute the product particle size control method described above, and has similar implementation principles and technical effects, which will not be described here again.

[0128] Figure 9 is a block diagram of an electronic device according to an example embodiment, please see Figure 9The electronic device 900 can include a processor 91 and a memory 92, wherein the processor 91 and the memory 92 can communicate; for example, the processor 91 and the memory 92 communicate through a communication bus 93, the memory 92 is configured to store instructions, and the processor 91 is configured to invoke the instructions in the memory to enable the electronic device to perform the product particle level control method shown in any of the above method embodiments.

[0129] The processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), or the like. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in the present application can be directly embodied as hardware processor execution, or executed by a combination of hardware and software modules in the processor.

[0130] The present application provides a computer readable storage medium, and the computer readable storage medium stores computer execution instructions; the computer execution instructions are executed by a processor to implement the product particle level control method of any of the above embodiments.

[0131] The present application provides a computer program product, and the computer program product includes a computer program; when the computer program is executed by a processor, the product particle level control method is implemented.

[0132] Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice in the art to which the application pertains. The specification and examples are to be regarded as exemplary only, and the true scope and spirit of the application are indicated by the following claims.

[0133] It should be understood that the application is not limited to the precise construction that has been described above and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is limited only by the appended claims.

Claims

1. A product size control method, characterized by, The application relates to a control device applied to a roller mill system, the roller mill system comprising a roller mill, and the method comprises the following steps: obtaining a first content value corresponding to a first extrusion roller frequency of the roller mill based on a preset fitting relationship between the content of the product particle size and the extrusion roller frequency; processing the first content value and a target content value of the product particle size based on a predictive control model to obtain a target frequency change amount for adjusting the extrusion roller frequency; adjusting the extrusion roller frequency of the roller mill based on the first extrusion roller frequency and the target frequency change amount; wherein the processing of the first content value and the target content value of the product particle size based on the predictive control model to obtain the target frequency change amount for adjusting the extrusion roller frequency comprises: constructing an optimization function among the content of the product particle size, the target content value and the frequency change amount based on the predictive control model; inputting the first content value and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount; if the unit frequency change amount is greater than a preset frequency adjustment threshold, the unit frequency change amount is taken as the target frequency change amount; if the unit frequency change amount is less than the preset frequency adjustment threshold, the first extrusion roller frequency is updated based on the sum of the unit frequency change amount and the first extrusion roller frequency, and a first content value corresponding to the updated first extrusion roller frequency is obtained, the first content value corresponding to the updated first extrusion roller frequency and the target content value of the product particle size are inputted into the optimization function to obtain a unit frequency change amount, and the steps are repeatedly executed until the sum of all the obtained unit frequency change amounts is greater than the preset frequency adjustment threshold, so that the sum of the obtained unit frequency change amounts is taken as the target frequency change amount.

2. The method of claim 1, wherein, the optimization function comprises: wherein, is an optimization function, is a first content value, is a target content value, is a unit frequency change amount, is a weight factor, is is a time instant.

3. The method of claim 1, wherein, before the step of obtaining a first content value corresponding to a first extrusion roller frequency of the roller mill based on a preset fitting relationship between the content of the product particle size and the extrusion roller frequency, the method further comprises: obtaining a historical extrusion roller frequency of the roller mill; after a time corresponding to a preset time length, obtaining a historical content of the product particle size output by the roller mill; wherein the preset time length represents a response time length between the change of the extrusion roller frequency of the roller mill and the content of the product particle size; performing numerical fitting based on the historical extrusion roller frequency and the historical content to obtain the preset fitting relationship.

4. The method of claim 1, wherein, the adjustment of the extrusion roller frequency of the roller mill based on the first extrusion roller frequency and the target frequency change amount comprises: adding the first extrusion roller frequency and the target frequency change amount to obtain an initial adjustment frequency; detecting the relationship between the initial adjustment frequency and a preset adjustment frequency range to obtain a relationship result; if the relationship result indicates that the initial adjustment frequency is located in the preset adjustment frequency range, adjusting the extrusion roller frequency based on the initial adjustment frequency; if the relationship result indicates that the value of the initial adjustment frequency is not located in the value of the preset adjustment frequency range, adjusting the extrusion roller frequency based on the extreme value in the preset adjustment frequency range.

5. The method of claim 1, wherein, The roller mill system further comprises a feeder, a feed belt and a feed bin connected in sequence, the product to be roller milled in the feeder enters the feed bin from the feed belt and enters the roller mill through the feed bin; Before the preset fitting relationship between the content of the product particle size and the frequency of the extrusion roller is used to obtain the first content value corresponding to the first frequency of the extrusion roller of the roller mill, the method further comprises: obtaining a target belt ore quantity of the feed belt, and performing proportional integral control on the frequency of the feeder based on the target belt ore quantity to control the amount of the product to be roller milled entering the roller mill; and / or, obtaining a target ore quantity of the feed bin, and performing proportional integral control on the frequency of the feed belt based on the target ore quantity to control the amount of the product to be roller milled entering the roller mill.

6. The method of claim 1, wherein, The preset fitting relationship between the content of the product particle size and the frequency of the extrusion roller is used to obtain the first content value corresponding to the first frequency of the extrusion roller of the roller mill, comprising: obtaining an initial content value corresponding to the first frequency of the extrusion roller based on the preset fitting relationship; correcting the initial content value based on proportional integral control to obtain the first content value.

7. A product size control device, characterized by A control device applied to a roller mill system, the roller mill system comprising a roller mill, the device comprising: a content value prediction module configured to obtain a first content value corresponding to a first frequency of an extrusion roller of the roller mill based on a preset fitting relationship between a content of a product particle size and a frequency of the extrusion roller; a frequency change measurement module configured to process the first content value and a target content value of the product particle size based on a prediction control model to obtain a target frequency change amount for adjusting the frequency of the extrusion roller; a frequency adjustment module configured to adjust the frequency of the extrusion roller of the roller mill based on the first frequency of the extrusion roller and the target frequency change amount; wherein the frequency change measurement module comprises: an optimization function establishment unit configured to construct an optimization function among the content of the product particle size, the target content value and the frequency change amount based on the prediction control model; a unit frequency change amount determination unit configured to input the first content value and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount; a first frequency change measurement unit configured to, if the unit frequency change amount is greater than a preset frequency adjustment threshold, take the unit frequency change amount as the target frequency change amount; a second frequency change measurement unit configured to, if the unit frequency change amount is less than the preset frequency adjustment threshold, repeatedly perform the steps of updating the first frequency of the extrusion roller based on a sum of the unit frequency change amount and the first frequency of the extrusion roller, obtaining a first content value corresponding to the updated first frequency of the extrusion roller, inputting the first content value corresponding to the updated first frequency of the extrusion roller and the target content value of the product particle size into the optimization function to obtain a unit frequency change amount, until the sum of all unit frequency change amounts obtained is greater than the preset frequency adjustment threshold, and taking the sum of the unit frequency change amounts obtained as the target frequency change amount.

8. An electronic device, comprising: The electronic device comprises a processor and a memory; the memory is configured to store instructions; and the processor is configured to execute the instructions in the memory, so that the electronic device performs the product particle level control method according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer execution instructions, and the computer execution instructions are executed by the processor to implement the product particle level control method according to any one of claims 1 to 6.

Images