Automatic control model for improving power of high-pressure roller mill

Abstract

This invention relates to the field of high-pressure roller mill technology and discloses an automatic control model for improving the power of high-pressure roller mills for pelletizing. The model includes: a field data acquisition module, a data processing and transmission module, an intelligent decision-making module, and a field equipment execution module. Through multi-parameter coupled zoned closed-loop automatic control and graded gradient fine-tuning, it can cover all operating conditions of roller mill feeding, material column level, edge material circulation, and roller mill speed. It not only controls conventional feeding and main machine speed parameters but also incorporates dynamic linkage control of material column height and edge material flow rate, stabilizing the material filling state in the roller pressing zone, increasing the effective power of the roller mill, and optimizing the material extrusion, crushing, and refining effect. Furthermore, relying on multi-source data preprocessing and closed-loop feedback technology, it achieves real-time linkage between the field acquisition equipment and the control module, eliminating the need for frequent manual parameter adjustments by operators and significantly reducing the workload of manual maintenance.

Description

Technical Field

[0001] This invention relates to the field of high-pressure roller mill technology, and more specifically discloses an automatic control model for improving the power of high-pressure roller mills for pellets. Background Technology

[0002] In the pelleting process, after the concentrate is dried, it must first pass through a metal and other foreign matter detection device before being sent to the buffer silo. A feeding system is installed below the buffer silo. To ensure uniform and stable feeding to the high-pressure roller mill, a straight material column silo approximately 3 meters high is installed above the feed inlet. Both the buffer silo and the straight material column silo are equipped with level gauges. Simultaneously, the high-pressure roller mill process is also equipped with an edge material circulation system to meet the requirements of subsequent pelletizing processes.

[0003] In the prior art, document CN115780006A discloses "An Intelligent Control Method for Material Weight of High-Pressure Roller Mill Based on Case Reasoning." This method utilizes a historical input-output case database to derive a material weight control model for the high-pressure roller mill based on case reasoning and a control model. This model serves as the input to the controller and effectively solves the problem of low efficiency in manual operation. The method includes: collecting data on the frequency, current, material weight, and belt conveyor current of the vibrating feeder; setting a target material weight value; establishing an optimization model for the material weight control process based on case reasoning; establishing a linear reasoning model based on the instance database; inputting the control quantity output from the determined specific operating condition control model into the intelligent controller; and establishing an intelligent control model.

[0004] The document CN120243252A discloses "a control method and device for a high-pressure roller mill system", which includes: during the operation of the high-pressure roller mill system, monitoring the actual buffer material level in the buffer chamber and the actual metering material level in the metering chamber; when the actual buffer material level is less than a preset buffer material level and the actual metering material level is within the preset metering material level range, determining whether the first actual material flow rate, the second actual material flow rate, and the third actual material flow rate meet a preset balance condition; if not, adjusting the actual material flow rate of the second belt and / or the third belt according to the first actual material flow rate to ensure the stability of material flow feeding in the high-pressure roller mill system.

[0005] While existing technologies optimize material weight control through case-based reasoning or stabilize feeding through flow balancing, thus improving automation and feeding uniformity to some extent, they only focus on controlling single material weight or regulating multiple bin levels and material flow balancing. They do not employ a control approach that couples the height of the straight material column with the flow rate of the edge material to determine the working conditions. They lack the logic for calculating parameters derived from the 30-second height change of the straight material column, and they lack a working condition-based graded handling and multi-cycle differentiated stepped feeding adjustment architecture. They cannot accurately lock the optimal material column height range, cannot improve the effective work power of the roller mill from the perspective of material filling stability, and are unable to achieve the production goals of optimizing the specific surface area of ​​powder and improving the physicochemical properties of green pellets. Summary of the Invention

[0006] The main technical problem solved by this invention is to provide an automatic control model for improving the power of high-pressure roller mills for pellets, which can solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, according to one aspect of the present invention, more specifically, an automatic control model for improving the power of high-pressure roller mills for pellets includes: a field data acquisition module, a data processing and transmission module, an intelligent decision-making module, and a field equipment execution module;

[0008] The field data acquisition module collects the real-time height of the straight material column, the instantaneous flow rate of the edge material, the instantaneous flow rate of the straight material column feed, and the original process parameters of the actual operating speed of the high-pressure roller mill.

[0009] The data processing and transmission module summarizes and stores the received raw process parameters, calculates the derived parameters of the 30s height change of the straight material column, and synchronously transmits the raw process parameters and derived parameters to the intelligent decision-making module.

[0010] The intelligent decision-making module divides the operating conditions based on the straight material column height range and the edge material flow threshold. It combines the 30-second change value of the straight material column height with the graded adjustment rules and outputs the straight material feeding adjustment value, the roller mill speed correction parameter, and the YGL belt start / stop interlock command.

[0011] The field equipment execution module drives the feeding speed regulation mechanism, the roller mill frequency conversion drive unit, and the YGL edge material belt conveyor to perform corresponding control actions according to the various control commands received.

[0012] Furthermore, the on-site data acquisition module includes: a material column and edge material detection module, a feeding metering module, and a roller mill speed acquisition module;

[0013] Material column and edge material detection module: Real-time acquisition of straight material column height and instantaneous edge material flow rate;

[0014] Feeding and metering module: Equipped with a belt scale to collect the instantaneous feed flow rate of the straight material column in real time online;

[0015] Roller mill speed acquisition module: It is equipped with the speed feedback element of the high-pressure roller mill frequency converter to acquire the actual operating speed of the high-pressure roller mill in real time.

[0016] Furthermore, the data processing and transmission module includes: a data aggregation module, a parameter calculation module, and a data interaction module;

[0017] Data aggregation module: Receives and caches all raw process parameters collected on-site;

[0018] Parameter calculation module: Using 30 seconds as a fixed timing period, it calculates the derived parameters of the height change of the straight material column in 30 seconds;

[0019] Data interaction module: It transmits the original process parameters and derived parameters to the intelligent decision-making module, and at the same time receives the control commands issued by the intelligent decision-making module and distributes them to the field equipment execution modules.

[0020] Furthermore, the intelligent decision-making module includes: a working condition differentiation and determination module, a feeding grading and control module, and a speed and interlock determination module;

[0021] Operating condition differentiation and determination module: It uses two dimensions, the height range of straight material column and the threshold of edge material flow, to divide multiple operating conditions.

[0022] Feeding grading and control module: Combines the height change of the straight material column in 30 seconds to generate feeding adjustment values ​​for two gears: 30t / h and 60t / h.

[0023] Speed ​​and Interlock Determination Module: Outputs roller mill speed correction parameters based on feed rate boundary values, and outputs YGL belt conveyor interlock start / stop commands based on the edge material range matched by the ultra-high material column.

[0024] Furthermore, the field equipment execution module includes: a feeding execution module, a roller mill speed regulation execution module, and a YGL interlock execution module;

[0025] Feeding execution module: Adjusts the instantaneous feed rate based on the received feed adjustment value;

[0026] Roller mill speed control module: Connects to the high-pressure roller mill drive frequency converter, and realizes the roller mill speed adjustment or adjustment according to the speed correction parameters;

[0027] YGL Interlock Execution Module: Connects to the YGL edge material conveyor control circuit and controls the start and stop of the conveyor based on interlock commands.

[0028] Furthermore, the working condition differentiation and determination module divides the working conditions into six categories:

[0029] Operating condition 1: 0m < H < 1.2m and M ≤ 280t / h;

[0030] Operating condition 2: 1.2m≤H≤1.7m and M≤280t / h;

[0031] Operating condition 3: 1.7m < H < 3.5m and M ≤ 280t / h;

[0032] Operating condition 4: 3.5m≤H≤4m and M≤280t / h;

[0033] Operating condition 5: 3.5m≤H≤4m and 280t / h<M≤320t / h;

[0034] Operating condition 6: 3.5m ≤ H ≤ 4m and M > 320t / h;

[0035] H represents the height of the straight material column, and M represents the instantaneous flow rate of the edge material.

[0036] Furthermore, the feeding grading and control module presets the safe feeding range for direct material as 820t / h < Q1 < 1120t / h; the system has three built-in fixed control cycles: T1=30s, T2=5s, and T3=15s; the feeding adjustment level is set to two levels: 30t / h and 60t / h per cycle; the speed and interlock judgment module locks the upper and lower limits of the roller mill speed control, with a minimum adjustment limit of 60% and a maximum adjustment limit of 95%; a height change judgment threshold of 0.3m is set to distinguish different feeding adjustment ranges.

[0037] Furthermore, in operating condition 1: the initial feed rate is increased by 60t / h at a time, and the cycle is checked with T1 as the period. Under the condition of 820t / h < Q1 < 1120t / h, when H1 < 0.3m, a single increase of 60t / h is made; when H1 ≥ 0.3m, a single increase of 30t / h is made. When Q1 reaches 1120t / h, the roller mill speed is decreased by 1% each time with T2 as the period, until the speed is 60%.

[0038] Operating Condition 2: Lock all adjustment parameters and do not output any feeding, speed, or YGL equipment adjustment commands;

[0039] Operating Condition 3: Initially, the feed rate is reduced by 60 t / h at a time, and the cycle is checked with T1 as the period. Under the condition of 820 t / h < Q1 < 1120 t / h, if H2 < 0.3m, the feed rate is reduced by 60 t / h at a time, and if H2 ≥ 0.3m, the feed rate is reduced by 30 t / h at a time. When Q1 drops to 820 t / h, the roller mill speed is increased by 1% at a time with T2 as the period, until the speed reaches 95%.

[0040] Operating conditions 4 and 6: Output a shutdown interlock signal to directly cut off the YGL belt running control circuit;

[0041] Operating Condition 5: The initial feed rate is reduced by 60t / h at once, and then reduced by 60t / h again every T3 cycle thereafter.

[0042] The beneficial effects of the automatic control model for improving the power of high-pressure roller mills for pellets in this invention are as follows: Through multi-parameter coupled zoned closed-loop automatic control and graded gradient fine-tuning, it can cover all working conditions of roller mill feeding, material column level, edge material circulation, and roller mill speed. It not only controls the parameters of conventional feeding and main machine speed, but also incorporates dynamic linkage control of material column height and edge material flow rate, stabilizing the material filling state in the roller pressing zone, improving the effective working power of the roller mill, and optimizing the material extrusion, crushing and refining effect; In addition, relying on multi-source data preprocessing and closed-loop feedback technology, it realizes real-time linkage between on-site acquisition equipment and control modules, eliminating the need for operators to manually change parameters frequently, and significantly reducing the manual operation and maintenance load; At the same time, relying on the ultra-high material column graded interlocking control technology, it differentiates the start and stop of the edge material belt, avoids material blockage and overflow faults, reduces the amount of bentonite added after the specific surface area of ​​the raw materials is increased, optimizes the strength and moisture content of green pellets, and improves the quality of finished pellets and subsequent roasting conditions. Attached Figure Description

[0043] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0044] Figure 1 This is a schematic diagram of the system module architecture;

[0045] Figure 2 This is a logical schematic diagram of the control model of the present invention. Detailed Implementation

[0046] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the present application can be combined with each other.

[0047] According to one aspect of the invention, such as Figures 1-2 As shown, an automatic control model for improving the power of a high-pressure roller mill for pelletizing is provided, including: a field data acquisition module that collects the real-time height of the straight feed column, the instantaneous flow rate of the edge material, the instantaneous flow rate of the straight feed column, and the raw process parameters of the actual operating speed of the high-pressure roller mill. This module includes:

[0048] Material column and edge material detection module: Real-time acquisition of straight material column height and instantaneous edge material flow rate;

[0049] In the existing straight material column silo with a design reference height of 3m, continuous material level detection components were installed in a segmented distributed layout from the bottom zero meter position to the top 4m extreme range. The installation points of the components were evenly distributed across the entire height range of 0-4m. All detection hardware was deliberately avoided in the area of ​​free fall impact of materials inside the silo and in the high incidence of powder adhesion and accumulation on the silo wall to prevent material from damaging the sensors and material from interfering with the height acquisition accuracy. The hardware wiring used shielded signal cables to connect to the IO acquisition terminals of the on-site PLC control system as close as possible. During the on-site commissioning phase, five sets of physical reference points were used sequentially for on-site calibration and calibration, including empty silo (H=0m), full load ultra-high material level (H=4m), optimal median material level of 1.2m, 1.7m, and ultra-high critical material level of 3.5m, to ensure that the digital signals output by the sensors could accurately map the actual metric height of the straight material column on site.

[0050] For the YGL edge material circulating conveyor belt, an online belt flow detection instrument is fixedly installed in the stable material loading section in the middle of the belt where the material is evenly spread and there is no material splashing. The instrument calculates the real-time edge material flow rate M per t / h based on the instantaneous self-weight of the material carried by the belt. The instrument calibration is carried out in advance by loading weights with two working conditions of 280t / h and 320t / h to ensure that the collected flow rate value matches the working condition judgment threshold accurately. All the original analog signals output by the material level sensor and the edge material flow meter are processed by the signal isolation module and the signal transmission module to resist interference and are uniformly converted into industrial electrical signals. The original collected data is transmitted to the data processing and transmission module in real time in an uninterrupted continuous transmission mode, completely abandoning the traditional crude collection method of manual on-site inspection and visual estimation of material level and edge material quantity.

[0051] Feeding and metering module: Equipped with a belt scale to collect the instantaneous feed flow rate of the straight material column in real time online;

[0052] Specifically, the entire belt scale adopts a split-type load-bearing frame structure and is installed as a whole in the middle section of the feed belt frame upstream of the straight material column bin, where there is no equipment vibration and the belt tension is uniform. This ensures that the material of the iron concentrate is completely placed on the load-bearing metering roller surface of the electronic scale throughout the entire conveying process. After the equipment is installed, the no-load zero-point tare calibration is first performed to eliminate the metering deviation caused by the self-weight of the frame and the self-weight of the belt. Then, standard counterweights are selected for multi-level loading calibration. The calibration range fully covers the system's preset safe feeding range of 820t / h-1120t / h. The instantaneous feed amount Q per unit t / h is calculated in real time based on the change of load. The electronic scale is equipped with a high-frequency pulse transmitter output terminal, and the real-time metering data is continuously sent out in the form of pulse signals.

[0053] It also includes integrated variable frequency speed control drive hardware for the feed belt, with the speed control circuit and the belt electronic scale data acquisition circuit electrically linked and bound. When the subsequent intelligent decision module issues a quantitative feeding adjustment command of 60t / h up / down or 30t / h fine adjustment, the variable frequency speed control hardware achieves precise quantitative increase or decrease of feed flow by changing the belt running linear speed. The speed control device reserves a dedicated communication wiring port, and the electronic scale metering data and the frequency converter operating status parameters are uniformly summarized and connected to the central control system acquisition bus.

[0054] Roller mill speed acquisition module: It is equipped with the speed feedback element of the high-pressure roller mill frequency converter to acquire the actual operating speed of the high-pressure roller mill in real time;

[0055] First, a pulse-type speed encoder is selected as the speed feedback component. It is coaxially locked and assembled at the end of the output shaft of the main drive motor of the high-pressure roller mill through a shock-absorbing coupling. The buffer structure is used to counteract the mechanical vibration generated by the operation of the roller mill body, so as to avoid the loss of encoder pulse signal and abnormal jump in speed data caused by vibration. The equipment is calibrated with the roller mill rated full speed corresponding to 100% of the reference speed scale. The calibration is carried out step by step downward to the lowest speed limit scale point of 60% of the system and upward to the highest speed limit scale point of 95%, completing the calibration of the full speed range.

[0056] Then, the main control chip of the inverter in the high-pressure roller mill is built in and collects the encoder output pulse signal in real time through the internal communication bus of the equipment. The actual running speed R of the roller mill is converted into a percentage format based on the pulse frequency. The inverter is equipped with a high-speed data register to continuously cache the real-time speed raw data at a millisecond refresh frequency.

[0057] Finally, the frequency converter reserves a standard industrial communication interface. The real-time speed data stored in the register is transmitted point-to-point over long distance to the data processing and transmission module through shielded communication cables, so as to realize the continuous uploading of the original parameters of the roller mill speed without delay, and avoid the control deviation of subsequent working condition judgment and speed adjustment due to data lag.

[0058] The data processing and transmission module summarizes and stores the received raw process parameters, calculates derived parameters of the 30-second height change of the straight material column, and synchronously transmits the raw process parameters and derived parameters to the intelligent decision-making module. This module includes:

[0059] Data aggregation module: Receives and caches all raw process parameters collected on-site;

[0060] Specifically, the four types of raw process parameters are partitioned and classified for storage based on the data register and loop stack cache architecture built into the PLC on site. The four types of raw parameters are the real-time height H of the straight material column and the instantaneous flow rate M of the edge material collected by the material column and edge material detection module, the instantaneous feed flow rate Q1 of the straight material column output by the belt electronic scale of the feeding metering module, and the actual operating speed R of the high-pressure roller mill transmitted by the frequency converter of the roller mill speed acquisition module.

[0061] At the hardware level, four independent register storage partitions are divided, and each parameter is configured with a dedicated fixed storage address. The isolated transmission industrial signals transmitted by the front-end acquisition module through shielded cables are continuously captured. After the signal is converted into a digital quantity by the PLC's internal analog-to-digital conversion unit, it is written to the corresponding partition register in real time. The first-in-first-out (FIFO) circular stack mechanism is used to continuously buffer the acquired data, which can completely retain the original sampling values ​​of all dimensions within at least 30 seconds of the cycle, avoiding the data loss problem caused by instantaneous signal fluctuations.

[0062] At the software level, data storage permissions are defined through the PLC background configuration program, distinguishing between read-only raw data areas and temporary calculation buffer areas. Direct rewriting of archived raw parameters by field equipment signals is prohibited. A data anomaly identification subroutine is configured synchronously. When abnormal operating conditions such as out-of-range parameters (H>4m, M>320t / h, Q1 exceeding the 820-1120t / h safe range, speed exceeding the 60%-95% speed regulation range), signal disconnection, null values, or numerical step jumps occur, the abnormal data points are automatically marked and the valid data collected at the previous moment is retained as temporary backup storage. All archived raw process parameters are in a standby state in real time, providing an uninterrupted, complete, and reliable raw data source for the parameter calculation module.

[0063] Parameter calculation module: Using 30 seconds as a fixed timing period, it calculates the derived parameters of the height change of the straight material column in 30 seconds;

[0064] First, the PLC system's built-in high-precision hardware timer triggers a fixed 30-second timing cycle start and stop action. The timer's timing reference relies on the industrial clock source of the field central control system for millisecond-level clock synchronization calibration to eliminate cycle calculation distortion caused by timing offset. At the moment of each timing start, the parameter calculation subroutine actively retrieves the initial sampled value H of the straight column reference height at the start of this cycle from the register of the data aggregation module. The retrieval action is completed by point-to-point fast addressing through the PLC's internal bus, and the time consumption of a single data addressing and reading is controlled within 10ms.

[0065] Then, after the hardware timer accumulates a 30-second cycle, the subroutine reads the sampled value H_end of the straight material column's end height at the end of the current cycle from the same data storage partition. After reading, it performs a difference calculation: H = H_end - H_beginning. This H is the derived parameter of the 30-second height change of the straight material column. The calculation process is simultaneously bound to a 0.3m height change judgment threshold. While calculating the value of H, it automatically compares the threshold value and marks the attribute label of H < 0.3m or H ≥ 0.3m, which is then stored along with the derived parameter. This is used by the intelligent decision-making module to distinguish between the 30t / h and 60t / h feeding adjustment levels.

[0066] Finally, after each 30-second cycle of derived parameter calculation is completed, the calculation result, along with the original H, M, Q1, and speed R parameters corresponding to the entire cycle, is packaged into a single data packet. The data packet is temporarily stored in a dedicated calculation result cache after the current cycle timestamp is added, waiting for the data interaction module to retrieve and transmit it. The timer is then automatically cleared and reset, and the next 30-second timing cycle begins immediately, realizing uninterrupted and continuous rolling calculation of derived parameters.

[0067] Data interaction module: It transmits the original process parameters and derived parameters to the intelligent decision-making module, and at the same time receives the control commands issued by the intelligent decision-making module and distributes them to the field equipment execution modules.

[0068] The first step is to use an industrial Profinet fieldbus communication architecture to achieve forward data downlink transmission. The bus communication rate is fixed at 100Mbps. After each round of parameter calculation and packaging is completed in 30 seconds, the data interaction subroutine encapsulates the original process parameters and H-derived parameters with attribute tags according to a fixed communication message format. The data inside the message is arranged in a fixed field order of H, M, Q1, mill speed R, and H. At the same time, the critical threshold parameters required for the division of six working conditions are embedded (1.2m, 1.7m, 3.5m, and 4m material column height boundary values, 280t / h and 320t / h edge material flow boundary values). The encapsulated message is uploaded to the PLC computing unit of the intelligent decision module in real time via a shielded communication cable. The transmission process is configured with a CRC cyclic redundancy check mechanism. When the message check fails, a secondary retransmission mechanism is automatically triggered to ensure that the intelligent decision module receives data without packet loss or error codes.

[0069] Following this, relying on the same industrial bus, the system receives three types of control command data from the intelligent decision-making module: direct material feeding adjustment values ​​(increase or decrease by 30t / h or 60t / h), roller mill speed percentage correction parameters, and YGL belt start / stop interlock switch commands. The data interaction module has a built-in instruction splitting logic subroutine that breaks down the message data according to the corresponding equipment: the feeding adjustment value is separately split and sent to the control terminal of the feed belt inverter corresponding to the feeding execution module; the roller mill speed correction parameters are directionally transmitted to the communication port of the high-pressure roller mill main drive inverter; and the YGL start / stop interlock switch commands are separately connected to the local control loop IO point of the YGL side material belt conveyor. The split and sent actions are synchronously matched with the three control cycle timing requirements of T1=30s, T2=5s, and T3=15s, and the control signals are output in time according to the corresponding cycle nodes to avoid conflicts in the actions of the field execution equipment caused by the simultaneous issuance of multiple instructions.

[0070] The intelligent decision-making module classifies operating conditions based on the straight material column height range and the edge material flow rate threshold. It combines the 30-second change in straight material column height with a tiered adjustment rule to output straight material feed adjustment values, mill speed correction parameters, and YGL belt start / stop interlock commands. This module includes:

[0071] Operating condition differentiation and determination module: It uses two dimensions, the height range of straight material column and the threshold of edge material flow, to divide multiple operating conditions.

[0072] Specifically, the system relies on the built-in threshold register of the intelligent decision-making PLC to pre-fix the boundary values ​​of six types of working conditions. The critical values ​​of the height of four straight material columns (1.2m, 1.7m, 3.5m, and 4m) and the boundary values ​​of the flow rate of two edge materials (280t / h and 320t / h) are pre-entered into the register for permanent storage. The PLC receives the real-time raw H and M data forwarded by the data interaction module through the Profinet bus, and sequentially retrieves the real-time material column height H to match the four height ranges. It also synchronously links the instantaneous flow rate of the edge material M to the two flow rate thresholds. After the two parameters are synchronously completed with the logical AND operation, the system automatically locks the single working condition number of the current equipment among the six types of working conditions. After the data packet is received in each 30-second cycle, a full working condition traversal judgment is immediately performed. The working condition code generated by the judgment is stored in a dedicated intermediate buffer register as the basis for subsequent feeding, speed, and interlocking logic operations. There is no manual parameter intervention or modification throughout the entire process.

[0073] Feeding grading and control module: Combines the height change of the straight material column in 30 seconds to generate feeding adjustment values ​​for two gears: 30t / h and 60t / h.

[0074] Specifically, the PLC retrieves the 30-second change in material column height (H) parameter with high / low indicators from the buffer register. It automatically distinguishes the adjustment level with a threshold of 0.3m. Under the premise that the instantaneous feeding Q1 of the straight material is within the safe range of 820t / h-1120t / h, the single-time large adjustment level of 60t / h is selected when H < 0.3m, and the single-time small adjustment level of 30t / h is selected when H ≥ 0.3m. The system binds to the T1=30s main verification cycle to read the real-time Q1 value to verify the feeding boundary. According to the feeding and subtraction rules corresponding to the six predetermined working conditions, the single feeding adjustment amount is quantitatively calculated, and a standardized flow adjustment digital signal is generated and stored in the instruction buffer area.

[0075] It also includes a built-in self-locking subroutine for upper and lower limits of flow rate. When the calculated adjusted theoretical feed rate touches the lower limit of 820t / h or the upper limit of 1120t / h, the feed increase / decrease command output is automatically locked, and the feed speed adjustment parameters are no longer sent. Only the mill speed adjustment calculation authority is retained, and all generated feed adjustment values ​​are uniformly encapsulated into control messages to wait for reverse transmission.

[0076] Speed ​​and Interlock Determination Module: Outputs roller mill speed correction parameters based on feed rate boundary values, and outputs YGL belt conveyor interlock start / stop commands based on the edge material range matched by the ultra-high material column.

[0077] First, the program captures the measured data of the instantaneous feeding of the straight material Q1 in the buffer register in real time. It uses the two feeding boundaries of 820t / h and 1120t / h as the trigger conditions for speed regulation. When Q1 rises to the upper limit of 1120t / h, the speed reduction logic is activated. When Q1 drops to the lower limit of 820t / h, the speed increase logic is activated. The speed regulation range of the roller mill is strictly locked at 60%-95%. The speed regulation action is performed according to a fixed cycle of T2=5s, with a single speed increase or decrease of 1%.

[0078] Then, for the ultra-high material column range of 3.5m≤H≤4m, the program retrieves the real-time edge material flow rate M and distinguishes between working conditions 4, 5, and 6 by benchmarking against the thresholds of 280t / h and 320t / h respectively. When working conditions 4 and 6 meet the judgment conditions, a hard interlock stop switch signal is generated instantly. Working condition 5 generates a 60t / h material drop command periodically according to T3=15s.

[0079] Finally, the speed percentage correction parameters and YGL switch interlock signals after all calculations are completed are packaged and grouped together, encapsulated into feedback communication messages according to the time-sharing distribution timing rules, and sent back to the data interaction module via the Profinet bus to complete the splitting and distribution.

[0080] The field equipment execution module, according to the received control commands, drives the feeding speed regulation mechanism, the roller mill frequency conversion drive unit, and the YGL edge material conveyor to perform corresponding control actions. This module includes:

[0081] Feeding execution module: Adjusts the instantaneous feed rate based on the received feed adjustment value;

[0082] Specifically, the system relies on the integrated variable frequency speed control hardware of the feed belt as the execution carrier. The inverter's communication port receives the 30t / h or 60t / h quantitative flow adjustment messages sent by the data interaction module via a shielded cable. After the inverter's internal program parses the flow increase or decrease data in the message, it accurately changes the belt running linear speed through a closed-loop speed control algorithm. The belt electronic scale synchronously transmits the actual instantaneous feed amount Q1 back to the front-end acquisition link to form a closed-loop verification. After a single 60t / h large adjustment or 30t / h fine adjustment instruction is executed, the local register latches the current operating frequency and waits for the T1=30s cycle to arrive before receiving the next round of adjustment instructions. It is strictly controlled within the safe feeding range of 820t / h-1120t / h. When the flow boundary is reached, the inverter locks the output frequency and no longer changes the speed.

[0083] Roller mill speed control module: Connects to the high-pressure roller mill drive frequency converter, and realizes the roller mill speed adjustment or adjustment according to the speed correction parameters;

[0084] Specifically, the high-pressure roller mill main frequency converter receives the speed percentage correction parameter through the industrial Profinet bus. After reading the instruction, the internal main control chip completes the speed increase or decrease of 1% in steps according to the T2=5s timing sequence. During the speed regulation process, the actual speed R fed back by the encoder in real time is continuously referenced. The system hardware logic locks the 60% minimum speed regulation lower limit and the 95% maximum speed regulation upper limit. When the speed calculated by the instruction reaches the limit, the frequency converter automatically blocks subsequent speed regulation instructions in the same direction and only retains the right to receive reverse speed regulation. The actual running speed is synchronously uploaded to the roller mill speed acquisition module in the reverse direction to complete the data closed loop.

[0085] YGL Interlock Execution Module: Connects to the YGL edge material conveyor control circuit and controls the start and stop of the conveyor based on interlock commands;

[0086] Specifically, the interlocking switch command is directly connected to the contactor coil control terminal of the YGL belt local electrical control circuit via the IO terminal. The shutdown command for conditions 4 and 6 is a hard interlocking signal. The power supply to the belt main contactor is directly cut off the moment the signal is turned on to achieve immediate shutdown. The feed reduction command for condition 5 is separately diverted to the feed execution module. The feed reduction operation is periodically executed at a time interval of T3=15s, with a rate of 60t / h. The start and stop control signals are synchronously connected to the field signal indicator circuit. The operation status is transmitted back to the data aggregation module register in real time for storage and recording.

[0087] To illustrate the effects achieved by this invention, we conducted an experiment in the high-pressure roller mill of the pelletizing unit at an ironmaking plant, as detailed below:

[0088] Experimental Objective

[0089] Based on the existing high-pressure roller mill equipment of a pellet production line in an ironmaking plant, an automatic control model was implemented on-site. The model's ability to stably control the material level of the straight feed column, the power enhancement effect of the high-pressure roller mill, and the improvement effect on the relevant process indicators of the subsequent green pellet products were verified by actual measurement.

[0090] Experimental materials

[0091] The experimental setup used was a complete set of high-pressure roller mills in the pelletizing unit of the ironmaking plant of Baosteel Zhanjiang Iron & Steel Co., Ltd. The original straight material column level gauge, feeding electronic scale, roller mill frequency conversion speed regulation system, YGL edge material belt and edge material flow detection equipment were used. The production material was the conventional iron concentrate raw material fed into the mill in the pelletizing process of the plant.

[0092] Experimental process

[0093] The experiment was carried out in two phases. Before the model was put into use, the production line maintained the original traditional production mode. On-site operators manually set the high-pressure roller mill to fix the feeding amount and equipment speed, and relied on manual observation and adjustment of equipment operation in real time.

[0094] Subsequently, the software and hardware deployment and parameter matching debugging of this automatic control model were completed on the high-pressure roller mill device. After the equipment signal docking and control logic download were completed, the system was switched to the fully automatic closed-loop control mode of this invention for long-term online industrial continuous production. The system continuously collects data on the height control of the straight material column, the operating power of the roller mill, the frequency of on-site manual operation, and production data related to the quality of green pellets, and compares the differences in various operating parameters between manual control and automatic model control.

[0095] Experimental results

[0096] After adopting the automatic control model, the hit rate of the high-pressure roller mill straight material column maintaining the optimal range of 1.2m-1.7m reached 90%.

[0097] The actual power output of the high-pressure roller mill increased from 200kW before the upgrade to 700kW.

[0098] After the equipment is automated, the frequency of manual adjustments by on-site operators has decreased significantly.

[0099] The improved efficiency of the roller mill optimizes the specific surface area of ​​the material, resulting in a reduction in the amount of bentonite used, a decrease in the moisture content of the finished material, and an increase in the number of green pellets falling and the compressive strength of the green pellets.

[0100] Experimental conclusions

[0101] This automatic control model can stably manage the height of the straight material column in a high-pressure roller mill, significantly improving the effective power of the high-pressure roller mill. It reduces the on-site manual operation and maintenance load, and optimizes the material crushing effect and the physical and chemical properties of green pellets. The entire control scheme has been successfully implemented in the pelletizing unit of a certain ironmaking plant, with excellent actual performance and good practical value.

[0102] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention are also within the protection scope of the present invention.

Claims

1. An automatic control model for improving the power of a high-pressure roller mill for pelletizing, characterized in that, include: The system includes a field data acquisition module, a data processing and transmission module, an intelligent decision-making module, and a field equipment execution module. The on-site data acquisition module collects the real-time height of the straight material column, the instantaneous flow rate of the edge material, the instantaneous flow rate of the straight material column feed, and the original process parameters of the actual operating speed of the high-pressure roller mill. The data processing and transmission module summarizes and stores the received raw process parameters, calculates the derived parameters of the 30s height change of the straight material column, and synchronously transmits the raw process parameters and derived parameters to the intelligent decision-making module. The intelligent decision-making module divides the operating conditions based on the straight material column height range and the edge material flow threshold. It combines the 30-second change value of the straight material column height with the graded adjustment rules and outputs the straight material feeding adjustment value, the roller mill speed correction parameter, and the YGL belt start / stop interlock command. The field equipment execution module drives the feeding speed regulation mechanism, the roller mill frequency conversion drive unit, and the YGL edge material belt conveyor to perform corresponding control actions according to the various control commands received.

2. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 1, characterized in that: The on-site data acquisition module includes: a material column and edge material detection module, a feeding and metering module, and a roller mill speed acquisition module; Material column and edge material detection module: Real-time acquisition of straight material column height and instantaneous edge material flow rate; Feeding and metering module: Equipped with a belt scale to collect the instantaneous feed flow rate of the straight material column in real time online; Roller mill speed acquisition module: Paired with the speed feedback element of the high-pressure roller mill frequency converter, it can acquire the actual operating speed of the high-pressure roller mill in real time.

3. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 1, characterized in that: The data processing and transmission module includes: a data aggregation module, a parameter calculation module, and a data interaction module; Data aggregation module: Receives and caches all raw process parameters collected on-site; Parameter calculation module: Using 30 seconds as a fixed timing period, it calculates the derived parameters of the height change of the straight material column in 30 seconds; Data interaction module: It transmits the original process parameters and derived parameters to the intelligent decision-making module, and at the same time receives the control commands issued by the intelligent decision-making module and distributes them to the field equipment execution modules.

4. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 1, characterized in that: The intelligent decision-making module includes: a working condition differentiation and determination module, a feeding grading and control module, and a speed and interlock determination module. Operating condition differentiation and determination module: It uses two dimensions, the height range of straight material column and the threshold of edge material flow, to divide multiple operating conditions. Feeding grading and control module: Combines the height change of the straight material column in 30 seconds to generate feeding adjustment values ​​for two gears: 30t / h and 60t / h. Speed ​​and Interlock Determination Module: Outputs roller mill speed correction parameters based on feed rate boundary values, and outputs YGL belt conveyor interlock start / stop commands based on the edge material range matched by the ultra-high material column.

5. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 1, characterized in that: The field equipment execution modules include: a feeding execution module, a roller mill speed regulation execution module, and a YGL interlock execution module; Feeding execution module: Adjusts the instantaneous feed rate based on the received feed adjustment value; Roller mill speed control module: Connects to the high-pressure roller mill drive frequency converter, and realizes the roller mill speed adjustment or adjustment according to the speed correction parameters; YGL Interlock Execution Module: Connects to the YGL edge material conveyor control circuit and controls the start and stop of the conveyor based on interlock commands.

6. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 4, characterized in that: The working condition differentiation and determination module divides the working conditions into six categories: Operating condition 1: 0m < H < 1.2m and M ≤ 280t / h; Operating condition 2: 1.2m≤H≤1.7m and M≤280t / h; Operating condition 3: 1.7m < H < 3.5m and M ≤ 280t / h; Operating condition 4: 3.5m≤H≤4m and M≤280t / h; Operating condition 5: 3.5m≤H≤4m and 280t / h<M≤320t / h; Operating condition 6: 3.5m ≤ H ≤ 4m and M > 320t / h; H represents the height of the straight material column, and M represents the instantaneous flow rate of the edge material.

7. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 4, characterized in that: The feeding grading and control module presets the safe feeding range for straight materials as 820t / h < Q1 < 1120t / h; the system has three built-in fixed control cycles: T1=30s, T2=5s, and T3=15s; the feeding adjustment level is set to two levels: 30t / h and 60t / h per cycle; the speed and interlock judgment module locks the upper and lower limits of the roller mill speed control, with a minimum adjustment limit of 60% and a maximum adjustment limit of 95%; a height change judgment threshold of 0.3m is set to distinguish different feeding adjustment ranges.

8. The automatic control model for improving the power of high-pressure roller mills for pelletizing according to claim 6, characterized in that: Operating Condition 1: Initially, the feed rate is increased by 60 t / h at a time, and the cycle is checked with T1 as the period. Under the condition of 820 t / h < Q1 < 1120 t / h, when H1 < 0.3m, a single feed rate of 60 t / h is added; when H1 ≥ 0.3m, a single feed rate of 30 t / h is added. When Q1 reaches 1120 t / h, the roller mill speed is decreased by 1% each time with T2 as the period, until the speed is 60%. Operating Condition 2: Lock all adjustment parameters and do not output any feeding, speed, or YGL equipment adjustment commands; Operating Condition 3: Initially, the feed rate is reduced by 60 t / h at a time, and the cycle is checked with T1 as the period. Under the condition of 820 t / h < Q1 < 1120 t / h, if H2 < 0.3m, the feed rate is reduced by 60 t / h at a time, and if H2 ≥ 0.3m, the feed rate is reduced by 30 t / h at a time. When Q1 drops to 820 t / h, the roller mill speed is increased by 1% at a time with T2 as the period, until the speed reaches 95%. Operating conditions 4 and 6: Output a shutdown interlock signal to directly cut off the YGL belt running control circuit; Operating Condition 5: The initial feed rate is reduced by 60t / h at once, and then reduced by 60t / h again every T3 cycle thereafter.

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