Automatic control system for abnormal vibration of roller press and roller press

Abstract

The present invention belongs to the field of mechanical equipment, and specifically relates to an automatic control system for abnormal vibration of a roller press, and a roller press using the automatic control system. The system is used to control the spindle motor speed, real-time feed amount and hydraulic pressure of the equipment step by step when the roller press vibrates abnormally; thereby restoring the over-limit vibration state of the roller press to be stable. The over-limit vibration control system includes: a vibration measuring mechanism, a roller speed regulating mechanism, a feed regulating mechanism, a hydraulic pressure regulating mechanism, and a controller. The vibration measuring mechanism uses an acceleration sensor to measure the vibration speed of the equipment. The controller is electrically connected to the vibration measuring mechanism, the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism. The controller includes a storage unit, a data acquisition unit, an over-limit evaluation unit, a first regulating unit, a second regulating unit, and a third regulating unit. The present invention can solve the problem of abnormal vibration caused by various factors in the existing roller press.

Description

Technical Field

[0001] The invention belongs to the field of mechanical equipment, and in particular relates to an automatic control system for abnormal vibration of a roller press, and a roller press adopting the automatic control system. Background Art

[0002] Roller press, also known as extrusion mill, roller mill or roller mill, is a highly efficient grinding equipment. In the raw material grinding process, since the downstream process has no special requirements for the particle morphology of the finished raw material grinding product, the roller press final grinding system can be used; in the cement grinding process, since the downstream commercial mixing station has requirements for the particle morphology of the finished cement grinding product, most of them adopt the configuration of roller press pre-grinding plus ball mill. The roller press squeezes and crushes the large particles and produces a large number of internal cracks, and then the ball mill finely grinds the finished roller press product to meet the requirements of particle size and particle morphology. Due to the high work efficiency of the roller press, it has been widely used in both raw material grinding and cement grinding. During the grinding process, the pressure, roller gap, speed and other parameters of the equipment need to be preset according to the physical properties of the raw materials. When the physical properties of the raw materials change, the pressure, roller gap, speed and other parameter settings of the roller press need to be adjusted in time to ensure the stability of production and the safety of the equipment.

[0003] In the existing cement grinding system, when the roller press vibrates, the on-site operator will suppress the vibration by adjusting the production, such as reducing the feed amount, lowering the pressure value, etc. If the DCS system is set up with equipment operation protection, the roller press vibration can also be suppressed in real time through automatic detection and automatic control.

[0004] Roller press equipment has different application scenarios during operation, and the properties of the processed materials vary greatly, so the causes of equipment vibration are often diverse. On this basis, the optimal control methods for different types of vibration should also be different. The vibration suppression control methods used by existing equipment usually only adjust the operating parameters of a single device, and use a simple negative feedback control logic. The control strategy is relatively monotonous and not adaptive. Therefore, when dealing with equipment vibration problems caused by materials of different properties, there may be poor control effects and delayed control effects. In extreme cases, inappropriate control strategies may even indirectly cause the roller press to gradually become unstable and damaged.

[0005] Abnormal vibration of roller press can cause equipment shutdown, discontinuous production, reduced production efficiency and increased costs. Therefore, how to effectively suppress equipment vibration is an important means to improve the stability and continuity of roller press operation. However, the effects of various vibration suppression methods in the prior art are still difficult to meet the requirements. Summary of the invention

[0006] In order to solve the problem that the conventional single-parameter control strategy adopted in the existing roller press has poor vibration suppression effect, resulting in insufficient equipment stability and continuity, the present invention provides an automatic control system for abnormal vibration of a roller press, and a roller press using the automatic control system.

[0007] The present invention is implemented by the following technical solutions:

[0008] An automatic control system for abnormal vibration of a roller press is used to adjust the spindle motor speed, real-time feed volume and hydraulic pressure of the equipment step by step when the roller press vibrates abnormally, so as to restore the over-limit vibration state of the roller press to stability. The over-limit vibration control system includes: a vibration measuring mechanism, a roller speed regulating mechanism, a feed regulating mechanism, a hydraulic pressure regulating mechanism and a controller.

[0009] Among them, the vibration measurement mechanism is used to measure the vibration speed of the roller press in real time during operation, and calculate the corresponding vibration offset Sh at each moment. The roller speed adjustment mechanism is used to dynamically adjust the speed v of the roller press spindle motor according to the received control instructions. The feed adjustment mechanism is used to dynamically adjust the real-time feed amount m of the electric feed device of the roller press according to the received control instructions. The hydraulic pressure adjustment mechanism is used to dynamically adjust the hydraulic pressure d of the roller press according to the received control instructions.

[0010] The controller is electrically connected to the vibration measuring mechanism, the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism. The controller is used to regulate the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism step by step according to the real-time measurement results of the vibration measuring mechanism. The controller includes a storage unit, a data acquisition unit, an over-limit evaluation unit, a first regulating unit, a second regulating unit and a third regulating unit.

[0011] In the controller, the data storage unit is used to store the preset maximum effect coefficient δ for speed regulation, feed rate regulation and hydraulic pressure regulation. 1max ,δ 2max ,δ 3max , a preset target deviation, and a speed single control rule table, a feed amount single control rule table, and a hydraulic pressure single control rule table. The data acquisition unit is used to obtain the real-time vibration deviation Sh of the roller press measured by the vibration measuring mechanism. The over-limit evaluation unit is used to evaluate in real time whether the current vibration state of the roller press exceeds the limit according to the real-time vibration deviation Sh of the roller press and the preset target deviation.

[0012] The first control unit is used to adjust the roller press according to the real-time vibration deviation Sh of the roller press and the maximum effect coefficient δ of the speed adjustment when the roller press is in the initial state or is still in the vibration over-limit state after being adjusted by the third control unit. 1maxA corresponding speed modulation amplitude Δv is calculated using the speed single control rule table, and a control instruction is generated for reducing the speed of the spindle motor of the roller press by a corresponding amplitude.

[0013] The second control unit is used to adjust the maximum effect coefficient δ according to the real-time vibration deviation Sh of the roller press and the feed amount when the roller press is still in a vibration overlimit state after being controlled by the first control unit. 2max A corresponding real-time feed amount amplitude modulation Δm is calculated from the feed amount single control rule table, and a control instruction for reducing the feed amount of the roller press by a corresponding amplitude is generated.

[0014] The third control unit is used to adjust the maximum effect coefficient δ of the roller press according to the real-time vibration deviation Sh of the roller press and the hydraulic pressure when the roller press is still in a vibration exceeding limit state after being adjusted by the second control unit. 3max A corresponding hydraulic pressure amplitude modulation Δd is calculated using the hydraulic pressure single control rule table, and a control instruction for reducing the hydraulic pressure of the roller press by a corresponding amplitude is generated.

[0015] As a further improvement of the present invention, the vibration measuring mechanism includes at least one acceleration sensor; the acceleration sensor is used to detect the real-time vibration velocity of the roller press. The vibration deviation Sh represents the proportion of the excess portion of the maximum allowable vibration velocity when the real-time vibration velocity of the roller press is greater than the maximum allowable vibration velocity.

[0016] As a further improvement of the present invention, in the feed adjustment mechanism, the real-time feed amount of the roller press is adjusted by adjusting the opening of the flap valve of the roller press to achieve the corresponding amplitude adjustment. The electric feed device includes a preset mapping relationship between different flap valve openings and real-time feed amounts; when the electric feed device receives a control instruction, the flap valve opening of the roller press is automatically adjusted to the corresponding value.

[0017] As a further improvement of the present invention, the speed single control rule table is used to characterize the speed adjustment ratio V corresponding to different first target adjustment amounts Sh during the vibration process of the roller press. rate , the two satisfy the following functional relationship:

[0018]

[0019] As a further improvement of the present invention, the feed amount single control rule table is used to characterize the real-time feed amount adjustment ratio M corresponding to different second target adjustment amounts Sh during the roller press vibration process. rate , the two satisfy the following functional relationship:

[0020]

[0021] As a further improvement of the present invention, the hydraulic pressure single control rule table is used to characterize the hydraulic pressure adjustment ratio D corresponding to different third target adjustment amounts Sh during the vibration process of the roller press. rate , the two satisfy the following functional relationship:

[0022]

[0023] As a further improvement of the present invention, in the data storage unit of the controller, the value ranges of the effect coefficients of speed regulation, feed rate regulation and hydraulic pressure regulation are: δ1∈[0.47,0.65], δ2∈[0.14,0.32], δ3∈[0.10,0.16];. The maximum effect coefficient δ 1max ,δ 2max ,δ 3max Select the maximum value of each effect coefficient, or select the best value from the range of effect coefficients based on expert experience in different application scenarios.

[0024] As a further improvement of the present invention, in the data storage unit of the controller provided by the present invention, the upper limit of the preset target deviation is 2%.

[0025] As a further improvement of the present invention, the instruction generation process of the first control unit, the second control unit and the third control unit is as follows:

[0026] (1) First, the product of the real-time vibration deviation and the maximum effect coefficient of each control index is used as the target adjustment amount of the vibration at the current stage.

[0027] (2) Then use the target adjustment amount to query the single control rule table corresponding to the control index to obtain the adjustment ratio of each control index.

[0028] (3) Then, the product of the adjustment ratio of each control indicator and the actual measured value of the corresponding control indicator is used as the target amplitude of the control indicator in the current stage.

[0029] (4) Finally, the corresponding control instructions are generated according to the amplitude modulation of each control index.

[0030] The present invention also includes a roller press, characterized in that it adopts the automatic control system for abnormal vibration of the roller press as described above.

[0031] The technical solution provided by the present invention has the following beneficial effects:

[0032] The present invention designs a new automatic control system for abnormal vibration of a roller press caused by different types of reasons. The automatic control system uses a multi-parameter hierarchical control method to adjust the operating parameters of the roller press; and designs a new control logic relative to the single-parameter control scheme. The automatic control system can achieve the best precision adjustment effect under different abnormal conditions; and significantly shortens the adjustment period for the roller press to return to a stable state.

[0033] The automatic control system for abnormal vibration of the roller press designed by the present invention can detect the abnormal state of the roller press in real time, intervene in the early stage of the roller press instability, and realize regulation as early as possible. At the same time, the new control strategy designed by the present invention is combined to accurately adjust the abnormal state of the equipment, thereby ensuring that the roller press can always be in the best operating state, reducing the failure rate of the equipment, ensuring the continuity of production, and improving the product processing efficiency under the unit energy consumption of the equipment.

[0034] In particular, the roller press using the automatic control system provided by the present invention can effectively ensure the stable operation of the roller press system under different working conditions and improve the continuity of production. At the same time, the control method also keeps the current of the equipment stable during operation without large fluctuations, thereby effectively reducing the operating power consumption of the equipment. For roller press equipment that needs to operate at high power for a long time, the application of this control system can significantly reduce the operating cost of the equipment and generate considerable economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0036] Figure 1 This is a flow chart of the steps of the method for controlling abnormal vibration of a roller press provided in Example 1 of the present invention.

[0037] Figure 2 This is a system framework diagram of the automatic control system for abnormal vibration of a roller press provided in Example 2 of the present invention.

[0038] Figure 3 This is a functional schematic diagram of the automatic control system for abnormal vibration of a roller press provided in Example 2 of the present invention.

[0039] Figure 4 This is a curve showing the variation of the vibration amount during the operation of the roller press of Example 3 of the present invention.

[0040] Figure 5 This is a curve of feed rate variation during operation of the roller press of Example 3 of the present invention.

[0041] Figure 6This is a curve of hydraulic pressure variation during operation of the roller press of Example 3 of the present invention.

[0042] Figure 7 This is a curve showing the change of the roll gap during the operation of the roller press of Example 3 of the present invention.

[0043] Figure 8 This is a curve showing the change of the equipment current during the operation of the roller press of Example 3 of the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0045] Example 1

[0046] This embodiment provides a method for controlling abnormal vibration of a roller press, which is mainly aimed at the body vibration problem of the roller press during actual operation. Generally speaking, during the operation of the roller press, the two rollers will run at a preset speed, so that the processing capacity of the roller press and the material rate of the feeding mechanism are adapted. At the same time, the hydraulic pressure of the roller press usually maintains a preset optimal state and works at a constant pressure. The above parameters jointly ensure the stable operation of the equipment. When the roller press is working, the material passes between the two rollers and is squeezed into powder under the pressure of the two rollers.

[0047] However, when the feeding situation of the equipment fluctuates to a large extent, the feeding situation will not match the processing capacity under the preset parameters of the equipment, which will cause the equipment to work abnormally. When the machine body is vibrating, the grinding effect of the roller press will be significantly worse, and the material processing rate will be reduced; the power of the roller press will increase, and the power consumption of the equipment will be increased. Of course, if the roller press is in an abnormal vibration state for a long time during operation, it may also cause damage to the equipment body. In severe cases, it may even cause the roller press to be scrapped. Therefore, it is very necessary to suppress the short-term vibration phenomenon of the roller press during operation.

[0048] The existing methods mainly adjust the operating status of the equipment through various single parameters to overcome the instantaneous jitter phenomenon. This method has obvious control effects under certain targeted abnormal conditions and can quickly restore the fuselage to normal. However, if the control method is not appropriate, it may aggravate the abnormality of the equipment. This embodiment provides a multi-parameter control method and designs a new control logic for different control methods; thereby achieving the ability to quickly solve the vibration problem of the fuselage caused by various abnormal phenomena; it has very high practical value.

[0049] Specifically, the method for controlling abnormal vibration of a roller press provided in this embodiment is as follows: Figure 1 As shown, the following steps are included:

[0050] S1: Preset the maximum effect coefficient δ for speed regulation, feed rate regulation and hydraulic pressure regulation respectively 1max ,δ 2max ,δ 3max The effect coefficient is used to characterize the proportional coefficient of the best control effect achieved by different control methods in the actual control process. This value is an expert experience value determined based on the data measured in the simulation experiment.

[0051] The probability of abnormal problems targeted by different control methods occurring in actual applications is different. At the same time, when different abnormal problems cause the failure state of fuselage vibration, the use of various control methods can often have an impact, but the results of suppressing fuselage vibration are different, and the adjustment range that can produce the best control effect is also different. In view of this feature, this embodiment combines simulation and real test measurement to determine the proportional coefficient of various control methods that can produce the best control effect in actual applications, and defines this coefficient as the effect coefficient δ.

[0052] In this embodiment, the value ranges of the effect coefficients δ1, δ2, and δ3 of the speed regulation, feed amount regulation, and hydraulic pressure regulation are: δ1∈[0.47,0.65], δ2∈[0.14,0.32], and δ3∈[0.10,0.16]. The preset maximum effect coefficient δ 1max ,δ 2max ,δ 3max The maximum value of each effect coefficient can be selected, or the best value can be selected from the range of effect coefficients according to expert experience in different application scenarios.

[0053] S2: The initial vibration deviation Sh0 of the roller press is collected in real time. When the initial vibration deviation Sh0 is higher than the target deviation, the roller press is subjected to primary regulation of the next step.

[0054] The vibration deviation Sh indicates the proportion of the excess portion relative to the maximum allowable vibration speed when the real-time vibration speed of the roller press is greater than the maximum allowable vibration speed.

[0055] The calculation formula is as follows:

[0056]

[0057] In this embodiment, the vibration deviation of the roller press is detected by an acceleration sensor. The target deviation represents the expected vibration deviation of the equipment set manually, and the target deviation is the threshold for triggering regulation; the upper limit of the target deviation set manually is 2%. That is, in the regulation logic of this embodiment, if the vibration deviation of the roller press reaches more than 2%, the equipment needs to be regulated, and if it is less than 2%, it is considered that the equipment is still in a safe state.

[0058] S3: In the primary control stage, only the speed v of the roller press is adjusted. The control process is as follows:

[0059] S31: The maximum effect coefficient δ of the speed adjustment 1max The product of the initial vibration deviation Sh0 is used as the first target adjustment amount.

[0060] S32: query a preset single speed control rule table according to the first target adjustment amount, and then generate the required speed modulation amplitude Δv. The speed modulation amplitude Δv represents the change amount of the adjusted target speed relative to the current speed.

[0061] The speed single control rule table is used to characterize the speed adjustment ratio V corresponding to different first target adjustment amounts Sh during the vibration process of the roller press rate The chart form of the speed single control rule table is shown in Table 1 below:

[0062] Table 1: Speed ​​single control rules for roller press vibration suppression process

[0063]

[0064] The speed single control rule table can also be expressed as the following functional relationship:

[0065]

[0066] in,

[0067] Speed ​​modulation Δv=V rate ×The current rotation speed v of the roller press.

[0068] S33: reducing the real-time rotation speed v of the roller press according to the rotation speed modulation Δv.

[0069] S34: Collect the initial vibration deviation Sh1 of the roller press after the speed is adjusted; determine whether the initial vibration deviation Sh1 is lower than the target deviation:

[0070] (1) If yes, the vibration suppression task is completed and the adjustment process ends.

[0071] (2) Otherwise, proceed to the next step of secondary regulation.

[0072] S4: In the secondary control stage, only the real-time feed amount m of the roller press is adjusted. The control process is as follows:

[0073] S41: The maximum effect coefficient δ of adjusting the feed amount 2max The product of the initial adjustment vibration deviation Sh1 is used as the second target adjustment amount.

[0074] S42: query a preset feed quantity single control rule table according to the second target adjustment amount, and then generate the required real-time feed quantity amplitude modulation Δm. The real-time feed quantity amplitude modulation Δm represents the change amount of the adjusted target real-time feed quantity relative to the current real-time feed quantity.

[0075] The feed rate single control rule table is used to characterize the real-time feed rate adjustment ratio M corresponding to different second target adjustment amounts Sh during the vibration process of the roller press. rate The chart form of the feed quantity single control rule table is shown in Table 2 below:

[0076] Table 2: Feed quantity single control rules table for roller press vibration suppression process

[0077]

[0078]

[0079] The feed quantity single control rule table can also be expressed as the following functional relationship:

[0080]

[0081] in,

[0082] Real-time feed amount modulation Δm=M rate ×The current real-time feed volume m of the roller press.

[0083] S43: lowering the real-time feed amount m of the roller press according to the real-time feed amount amplitude modulation Δm.

[0084] S44: Collect the secondary vibration deviation Sh2 of the roller press after the real-time feed amount is adjusted; determine whether the secondary vibration deviation Sh2 is lower than the target deviation:

[0085] (1) If yes, the vibration suppression task is completed and the adjustment process ends.

[0086] (2) Otherwise, proceed to the final control step of the next step.

[0087] S5: In the final control stage, only the hydraulic pressure d of the roller press is adjusted. The control process is as follows:

[0088] S51: The maximum effect coefficient δ of hydraulic pressure adjustment 3max The product of the secondary adjustment vibration deviation Sh2 is used as the third target adjustment amount.

[0089] S52: query a preset hydraulic pressure single control rule table according to the third target adjustment amount, and then generate the required hydraulic pressure amplitude modulation Δd. The hydraulic pressure amplitude modulation Δd represents the change amount of the adjusted target hydraulic pressure relative to the current hydraulic pressure.

[0090] The hydraulic pressure single control rule table is used to characterize the hydraulic pressure adjustment ratio D corresponding to the third target adjustment amount Sh during the vibration process of the roller press rate The chart form of the hydraulic pressure single control rule table is shown in Table 3 below:

[0091] Table 3: Hydraulic pressure single control rules for roller press vibration suppression process

[0092]

[0093] The hydraulic pressure single control rule table can also be expressed as the following functional relationship:

[0094]

[0095] in,

[0096] Hydraulic pressure modulation Δd=D rate × The current hydraulic pressure d of the roller press.

[0097] S53: Reduce the hydraulic pressure d of the roller press according to the hydraulic pressure amplitude modulation Δd.

[0098] S54: Collect the final adjustment vibration deviation Sh3 of the roller press after the hydraulic pressure is adjusted; determine whether the final adjustment vibration deviation Sh3 is lower than the target deviation:

[0099] (1) If yes, the vibration suppression task is completed and the adjustment process ends.

[0100] (2) Otherwise, return to step S3 and perform the next round of control again.

[0101] It should be noted that this embodiment adopts a strategy of multi-parameter hierarchical regulation, which is different from the synchronization strategy of multi-parameter fusion regulation. The priorities of various control means in this embodiment are different; and the effect coefficient is also different from the weight coefficient in the multi-parameter fusion regulation scheme. An obvious difference is that the sum of the effect coefficients corresponding to the various control means used in the scheme of this embodiment may not be 1. Another obvious advantage of using the effect coefficient of this embodiment to guide the regulation process is that it can avoid excessive regulation of the operating status of the equipment.

[0102] Example 2

[0103] The present embodiment provides an automatic control system for abnormal vibration of a roller press. The system is used to automatically regulate the abnormal vibration state of the equipment during operation by using the control method for abnormal vibration of the roller press as in Example 1 when abnormal vibration occurs in the roller press, thereby restoring the over-limit vibration state of the roller press to stability.

[0104] like Figure 2As shown, the over-limit vibration control system provided in this embodiment includes: a vibration measuring mechanism, a roller speed regulating mechanism, a feed regulating mechanism, a hydraulic pressure regulating mechanism, and a controller.

[0105] The vibration measuring mechanism is used to measure the vibration speed of the roller press in real time during operation and calculate the corresponding vibration offset Sh at each moment. The roller speed regulating mechanism is used to dynamically adjust the speed v of the roller press spindle motor according to the received control command. The feed regulating mechanism is used to dynamically adjust the real-time feed amount m of the electric feed device of the roller press according to the received control command. The hydraulic pressure regulating mechanism is used to dynamically adjust the hydraulic pressure d of the roller press according to the received control command.

[0106] Specifically, the vibration measuring mechanism uses an acceleration sensor for measurement. The roller speed regulating mechanism adjusts the speed of the roller press spindle motor through a frequency converter. The feed regulating mechanism adjusts the real-time feed amount of the roller press by controlling the opening of the roller press flap valve. The hydraulic pressure regulating mechanism adjusts the hydraulic pressure of the roller press through a hydraulic control system.

[0107] The controller is electrically connected to the vibration measuring mechanism, the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism. The controller is used to obtain the vibration deviation Sh detected by the vibration measuring mechanism. The method of steps S1-S5 in Example 1 is used to generate real-time control instructions sent to the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism. Thus, the equipment speed, real-time feed amount and hydraulic pressure are dynamically adjusted according to the over-limit degree of the roller press vibration, so as to quickly restore the roller press to stability.

[0108] Specifically, Figure 3 As shown, the controller of this embodiment includes a storage unit, a data acquisition unit, an over-limit evaluation unit, a first control unit, a second control unit, and a third control unit. The data storage unit adopts a FLASH memory or EPROM memory that has electronic erasable and programmable performance, and will not lose data due to power failure and can quickly read data.

[0109] The data storage unit is used to store the preset maximum effect coefficient δ for speed regulation, feed rate regulation and hydraulic pressure regulation. 1max ,δ 2max ,δ 3max ; preset target deviation; and speed single control rule table, feed volume single control rule table and hydraulic pressure single control rule table. The above data are used as system parameters of the automatic control system.

[0110] The data acquisition unit is used to obtain the real-time vibration deviation Sh of the roller press measured by the vibration measuring mechanism.

[0111] The over-limit evaluation unit is a comparator, and is used to evaluate in real time whether the current vibration state of the roller press is over-limit according to the real-time vibration deviation Sh of the roller press and the preset target deviation.

[0112] The first control unit is used to adjust the roller press according to the real-time vibration deviation Sh of the roller press and the maximum effect coefficient δ of the speed adjustment when the roller press is in the initial state or is still in the vibration over-limit state after being adjusted by the third control unit. 1max A corresponding speed modulation amplitude Δv is calculated using the speed single control rule table, and a control instruction is generated for reducing the speed of the spindle motor of the roller press by a corresponding amplitude.

[0113] The second control unit is used to adjust the maximum effect coefficient δ according to the real-time vibration deviation Sh of the roller press and the feed amount when the roller press is still in a vibration overlimit state after being controlled by the first control unit. 2max A corresponding real-time feed amount amplitude modulation Δm is calculated from the feed amount single control rule table, and a control instruction for reducing the feed amount of the roller press by a corresponding amplitude is generated.

[0114] The third control unit is used to adjust the maximum effect coefficient δ of the roller press according to the real-time vibration deviation Sh of the roller press and the hydraulic pressure when the roller press is still in a vibration exceeding limit state after being adjusted by the second control unit. 3max A corresponding hydraulic pressure amplitude modulation Δd is calculated using the hydraulic pressure single control rule table, and a control instruction for reducing the hydraulic pressure of the roller press by a corresponding amplitude is generated.

[0115] The instruction generation process of the first control unit, the second control unit and the third control unit is as follows:

[0116] (1) First, the product of the real-time vibration deviation and the maximum effect coefficient of each control index is used as the target adjustment amount of the vibration at the current stage.

[0117] (2) Then use the target adjustment amount to query the single control rule table corresponding to the control index to obtain the adjustment ratio of each control index.

[0118] (3) Then, the product of the adjustment ratio of each control indicator and the actual measured value of the corresponding control indicator is used as the target amplitude of the control indicator in the current stage.

[0119] (4) Finally, the corresponding control instructions are generated according to the amplitude modulation of each control index.

[0120] It should be emphasized that the abnormal vibration of the roller press during operation is usually only a short-term phenomenon. When the fault factors causing the abnormality are eliminated, the roller press itself will slowly return to normal. Therefore, the automatic control system in this embodiment will only adjust the operating parameters of the roller press when the roller press vibrates severely. When the roller press returns to normal and runs stably for a period of time, the system will also readjust the operating parameters of the roller press to the initial state. Or readjust the parameters according to the instructions of the technicians, and then use them to complete the grinding processing tasks of various materials.

[0121] Example 3

[0122] This embodiment provides a roller press, which adopts the automatic control system for abnormal vibration of the roller press as in Embodiment 2. Therefore, the spindle motor speed, the real-time feed amount of the equipment and the dual hydraulic pressure can be adaptively adjusted according to the operating state of the equipment by using the method in Embodiment 1 during operation. This keeps the operating state of the equipment stable and suppresses abnormal vibration of the machine body during operation.

[0123] In order to verify the effectiveness of the solution provided by this embodiment, this embodiment downloaded historical data of the operation process from the roller press; and analyzed the vibration suppression process of the roller press in this embodiment based on the data. Figure 4 The vibration curve of the roller press over a period of time is shown. From the analysis of the curve, we can see that in the early stage, the vibration speed of the roller press fluctuated greatly, and the vibration speed was maintained at a high level, higher than 0.47mm / s. However, after a period of adaptive adjustment, the vibration speed of the equipment returned to "calm" and remained at 0.37-0.38mm / s, with a drop of more than 19%. At the same time, the analysis of Figure 5-7 From the changing curves of feed rate, hydraulic pressure and roll gap in the same period, it can be seen that during the vibration suppression process, the feed rate and hydraulic pressure were indeed appropriately lowered. The feed rate dropped from nearly 230t / h to about 210t / h, and the hydraulic pressure dropped from about 8.50mPa to about 7.80mPa. Figure 7 In the curve, there is no obvious linear relationship between the adjustment of the roll gap and the vibration of the equipment. The control process of the equipment is indeed consistent with the control ideas provided in Examples 1 and 2; and the reduction of equipment vibration also verifies the effectiveness of the control strategy in this embodiment.

[0124] In particular, observe that Figure 8The trend of the equipment current change during the same period shown in the figure shows that, after the regulation of the automatic control system in this embodiment, the equipment current dropped from nearly 80A in the early stage to about 75A in the late stage, while the system output and quality remained stable, thus achieving the goal of reducing the equipment operation energy consumption. At the same time, the analysis of the image also shows that: in the early stage of regulation, the equipment current fluctuates greatly, which is the impact of the regulation process; it also reflects the conclusion that the operating current is related to the working state of the equipment and the amplitude of abnormal vibration.

[0125] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatic control system for abnormal vibration of a roller press, characterized in that: It is used to control the spindle motor speed, real-time feed volume and hydraulic pressure of the equipment step by step when the roller press vibrates abnormally, so as to restore the over-limit vibration state of the roller press to stability. The control system includes: A vibration measuring mechanism, which is used to measure the vibration velocity of the roller press in real time during operation and calculate the corresponding vibration deviation Sh at each moment; A roller speed adjustment mechanism, which is used to dynamically adjust the speed v of the roller press spindle motor according to the received control command; A feed regulating mechanism, which is used to dynamically adjust the real-time feed amount m of the electric feed device of the roller press according to the received control command; A hydraulic pressure regulating mechanism, which is used to dynamically adjust the hydraulic pressure d of the roller press according to the received control command; A controller, which is electrically connected to the vibration measuring mechanism, the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism; and is used to regulate the roller speed regulating mechanism, the feed regulating mechanism and the hydraulic pressure regulating mechanism step by step according to the real-time measurement result of the vibration measuring mechanism; wherein the controller includes a storage unit, a data acquisition unit, an over-limit evaluation unit, a first regulating unit, a second regulating unit, and a third regulating unit; The storage unit is used to store the preset maximum effect coefficient δ for speed regulation, feed quantity regulation and hydraulic pressure regulation respectively. 1max ,δ 2max ,δ 3max , preset target deviation, and speed single control rule table, feed volume single control rule table and hydraulic pressure single control rule table; The data acquisition unit is used to obtain the real-time vibration deviation Sh of the roller press measured by the vibration measuring mechanism; The over-limit evaluation unit is used to evaluate in real time whether the current vibration state of the roller press is over-limit according to the real-time vibration deviation Sh of the roller press and the preset target deviation; The first control unit is used to adjust the roller press according to the real-time vibration deviation Sh of the roller press and the maximum effect coefficient δ of the speed adjustment when the roller press is in the initial state or is still in the vibration over-limit state after being adjusted by the third control unit. 1max A corresponding speed modulation amplitude Δv is calculated using the speed single control rule table, and a control instruction is generated for reducing the speed of the spindle motor of the roller press by a corresponding amplitude; The second control unit is used to adjust the maximum effect coefficient δ according to the real-time vibration deviation Sh of the roller press and the feed amount when the roller press is still in a vibration overlimit state after being controlled by the first control unit. 2max and the feed quantity single control rule table to calculate a corresponding real-time feed quantity amplitude modulation Δm, and generate a control instruction for reducing the feed quantity of the roller press by a corresponding amplitude; The third control unit is used to adjust the maximum effect coefficient δ of the hydraulic pressure according to the real-time vibration deviation Sh of the roller press when the roller press is still in a vibration overlimit state after being adjusted by the second control unit. 3max A corresponding hydraulic pressure amplitude modulation Δd is calculated using the hydraulic pressure single control rule table, and a control instruction for reducing the hydraulic pressure of the roller press by a corresponding amplitude is generated.

2. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: The vibration measuring mechanism includes at least one acceleration sensor, which is used to detect the real-time vibration velocity of the roller press; the vibration deviation Sh represents the proportion of the excess portion of the maximum allowable vibration velocity when the real-time vibration velocity of the roller press is greater than the maximum allowable vibration velocity.

3. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: In the feed adjustment mechanism, the real-time feed amount of the roller press is adjusted to a corresponding amplitude by adjusting the opening of the flap valve of the roller press; a mapping relationship between different flap valve openings and real-time feed amounts is preset in the electric feeding device; when the electric feeding device receives a control instruction, the flap valve opening of the roller press is automatically adjusted to the corresponding value.

4. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: The speed single control rule table is used to characterize the speed adjustment ratio V corresponding to the first target adjustment amount Sh during the vibration process of the roller press rate , the two satisfy the following functional relationship:

5. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: The feed amount single control rule table is used to characterize the real-time feed amount adjustment ratio M corresponding to the second target adjustment amount Sh during the roller press vibration process. rate , the two satisfy the following functional relationship:

6. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: The hydraulic pressure single control rule table is used to characterize the hydraulic pressure adjustment ratio D corresponding to the third target adjustment amount Sh during the vibration process of the roller press. rate , the two satisfy the following functional relationship:

7. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: In the data storage unit of the controller, the value ranges of the effect coefficients of speed regulation, feed rate regulation and hydraulic pressure regulation are: δ1∈[0.47,0.65], δ2∈[0.14,0.32], δ3∈[0.10,0.16]; the maximum effect coefficient δ 1max ,δ 2max ,δ 3max Select the maximum value of each effect coefficient, or select the best value from the range of effect coefficients based on expert experience in different application scenarios.

8. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: In the data storage unit of the controller, the upper limit of the preset target deviation is 2%.

9. The automatic control system for abnormal vibration of a roller press according to claim 1, characterized in that: The instruction generation process of the first control unit, the second control unit and the third control unit is as follows: (1) First, the product of the real-time vibration deviation and the maximum effect coefficient of each control index is used as the target adjustment amount of the vibration amount at the current stage; (2) Using the target adjustment amount, query the single control rule table corresponding to the control index to obtain the adjustment ratio of each control index; (3) Then, the product of the adjustment ratio of each control index and the measured value of the corresponding control index is used as the target amplitude adjustment of the control index at the current stage; (4) Finally, the corresponding control instructions are generated according to the amplitude modulation of each control index.

10. A roller press, characterized in that: It adopts the automatic control system for abnormal vibration of the roller press as described in any one of claims 1-9.

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