Method and device for improving output of coal mill

Abstract

The invention provides a method and device for improving the output of a coal mill, and the method comprises the steps: constructing a parameterized model containing a grinding roller-lining plate gap and coal particle distribution, determining a difference value between the grinding roller-lining plate gap and a set gap, and correspondingly adjusting the positions of a grinding roller and a lining plate; determining a collaborative optimization relationship between the feeding speed and the grinding disc rotating speed, establishing an ideal nonlinear constraint between the feeding speed and the grinding disc rotating speed, and determining an ideal grinding disc rotating speed or an ideal feeding speed; a ventilation optimization model is constructed, the ventilation volume is corrected based on the air field information, quantitative correlation between the ventilation volume and the pulverized coal suspension speed is established, and the opening degree of an air door is correspondingly adjusted; a PID controller is adopted to control mill parameters; building a digital twin architecture, and updating the model parameters of the steps in real time; according to the method, the internal structure and operation parameters of the coal mill are accurately adjusted through the parameterized model construction and multi-physics field coupling calculation technology, the grinding roller-lining plate gap, the feeding speed and the grinding disc rotating speed are optimized, the air volume is accurately regulated and controlled, and the output and operation efficiency of the coal mill is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of coal processing, and in particular to a method and a device for improving the output of a coal mill. Background Art

[0002] In the industrial fields of electricity, heat production and coal processing, coal mill is one of the key equipment. With the continuous growth of global energy demand, thermal power generation, as one of the main power generation methods, has increasingly higher performance requirements for coal mills. In recent years, coal mill technology has developed in the direction of large-scale, high-efficiency and intelligentization. In terms of large-scale, the unit capacity of coal mills is constantly increasing to meet the needs of large-scale power generation units, reduce the number of equipment, and reduce system complexity and cost. During the operation of the coal mill, it is difficult to accurately control the gap between the grinding roller and the liner and the distribution of coal particles; the existing technology cannot fully consider the dynamic changes of the grinding roller stress distribution and the coal particle distribution over time, resulting in untimely or inaccurate gap adjustment, affecting the grinding effect and the output of the coal mill; there is a lack of effective methods for the coordinated optimization of the feed speed and the grinding disc speed; the relationship between the two is complex, and it is difficult for the existing technology to establish an accurate mathematical model to determine their ideal operating state. Adjustments are often made based on experience, and the best match between the two cannot be achieved, which limits the grinding efficiency of the coal mill; in terms of the ventilation system, the actual ventilation air volume is difficult to accurately adjust according to the real-time operating conditions of the coal mill; due to the mutual influence of air duct characteristics, air physical properties, wind pressure, wind speed and other factors, the existing ventilation optimization methods cannot accurately calculate and control the ventilation air volume, affecting the suspension and transportation of coal powder, thereby reducing the overall efficiency of the coal mill; It can be seen that the art is in urgent need of a method and device for improving the output of a coal mill to solve the above-mentioned problems. Summary of the invention

[0003] The present invention provides a method and device for improving the output of a coal mill, aiming to solve the problems existing in the above-mentioned prior art. By constructing a parameterized model and multi-physical field coupling calculation technology, the internal structure and operating parameters of the coal mill can be accurately adjusted, the grinding roller-liner gap, feed speed and grinding disc speed can be optimized, the ventilation air volume can be accurately controlled, and the output and operating efficiency of the coal mill can be effectively improved.

[0004] In one aspect, the present invention provides a method for improving the output of a coal mill, comprising: Step 1: Based on the coal quality characteristics, the internal geometry of the mill is dynamically modeled, a parametric model including the roller-liner gap and coal particle distribution is constructed, the difference between the roller-liner gap and the set gap is determined, and the positions of the roller and liner are adjusted accordingly; Step 2: Using multi-physics field coupling calculation, determine the coordinated optimization relationship between the feed speed and the grinding disc speed, establish an ideal nonlinear constraint between the two, substitute the feed speed or the grinding disc speed into the ideal nonlinear constraint, and determine the ideal grinding disc speed or the ideal feed speed; Step 3: Construct a ventilation optimization model, correct the ventilation air volume based on the air field information, obtain the actual ventilation air volume, and establish a quantitative relationship between it and the coal powder suspension velocity; compare the current actual ventilation air volume with the preset ideal air volume, and adjust the air door opening accordingly; Step 4: Use PID controller to control mill parameters; Step 5: Build a digital twin architecture and update the model parameters of the above steps in real time through multispectral sensing and data fusion technology.

[0005] According to a method for improving the output of a coal mill provided by the present invention, in step 1, the parameterized model is used to determine the roller-liner gap, specifically: ； in, is the roller-liner gap, is the number of grinding rollers; It is the stress distribution function of the grinding roller surface, which reflects the stress distribution of the grinding roller surface and is determined based on the grinding roller model or experiment; is the coal particle size distribution matrix, which is used to quantify the distribution characteristics of coal particles; is the axial coordinate of the grinding roller surface, that is, the stress distribution function of the grinding roller surface Variable parameters; is a time variable; the grinding roller-liner gap It is used to reflect the dynamic value of the roller-liner gap considering the roller stress distribution and coal particle distribution changing with time; Wherein, the coal particle size distribution matrix satisfies: ； in, It represents the proportion of particles in the jth particle size interval in the i-th grinding roller area, and m is the particle size classification number; this matrix is ​​used to reflect the distribution ratio of coal particles in different particle size intervals in different grinding roller areas; Get the rated clearance , calculate the roller-liner gap With rated clearance The position of the grinding roller and lining plate is adjusted based on the difference.

[0006] According to a method for improving the output of a coal mill provided by the present invention, in step 2, the coordinated optimization relationship between the feed speed and the grinding disc speed is determined, and an ideal nonlinear constraint between the two is established. The ideal nonlinear constraint between the two is: ; in, and is the inherent constant of the device; is the coal density; The real-time power of the motor; is the rate of change of the gap between the grinding roller and the liner over time; this formula is used to reflect the dynamic relationship between the rate of change of the feed speed and the grinding disc speed and the change of the gap between the grinding roller and the liner, and then determine the feed speed With grinding disc speed Ideal nonlinear constraints; The current feed speed Or grinding disc speed Substituting into the formula, the ideal grinding disc speed is calculated Or ideal feed rate ; Based on ideal grinding disc speed Or ideal feed rate Adjust the grinding disc speed or feed speed accordingly.

[0007] According to a method for improving coal mill output provided by the present invention, in step three, the ventilation optimization model is: ； in, is the diameter of the air duct; is the air density; is the wind pressure field; is the axial coordinate; Represents the rate of change of wind pressure field along the axial direction; is the air dynamic viscosity; is the wind speed field; Representing the velocity field The Laplace operator of is the Reynolds number, and ; Income The current actual ventilation air volume corrected based on the air duct characteristics, air physical properties, wind pressure and wind speed factors is compared with the preset ideal air volume and the damper opening is adjusted accordingly.

[0008] According to a method for improving the output of a coal mill provided by the present invention, in step 4, the control law of the PID controller is: ； in, The load deviation corresponds to adjusting the position of the grinding roller liner, adjusting the grinding disc speed or the feed speed, and adjusting the air door opening. , , They are proportional, integral, and differential coefficients, respectively, determined based on experience or experiment; is the controller output; The corresponding adjustment of the position of the grinding roller lining, the adjustment of the grinding disc speed or the feed speed, and the adjustment of the air door opening are achieved by the PID controller.

[0009] According to a method for improving the output of a coal mill provided by the present invention, in step five, the digital twin architecture includes: The physical entity layer deploys a multi-spectral CCD sensor array, which includes a near-infrared band sensor for measuring the moisture distribution of coal powder, a terahertz band sensor for detecting micro-cracks on the surface of the grinding roller, and an ultraviolet band sensor for monitoring the combustion characteristics of coal powder; The data fusion layer uses tensor decomposition technology to process multi-source heterogeneous data for multi-physics field coupling modeling and PID control; The model update layer implements online parameter identification based on the variational autoencoder to ensure the consistency between the model and the actual operating status.

[0010] In another aspect, the present invention provides a device for improving the output of a coal mill, based on a method for improving the output of a coal mill, comprising: The geometric modeling and adjustment equipment includes a stress sensor and a multi-spectral particle analyzer; the stress sensor is installed on the surface of the grinding roller to collect the surface stress data of the grinding roller in real time and determine the stress distribution function of the grinding roller surface; the multi-spectral particle analyzer monitors the coal particles in real time to obtain the coal particle size distribution data, and then constructs the coal particle size distribution matrix; The geometric modeling and adjustment device has a built-in microprocessor, which calculates the roller-liner gap through the parameterized model according to the data transmitted by the stress and particle distribution monitoring unit; compares the calculated gap value with the rated gap to obtain the difference; and sends a control instruction to the roller and liner position adjustment mechanism through the PID controller according to the difference to adjust the position of the roller and liner; Multi-physics field coupling control equipment, which consists of a speed sensor, a power sensor and a density sensor; the speed sensor is used to measure the grinding disc speed, the power sensor monitors the real-time power of the motor, and the density sensor detects the coal density; The multi-physical field coupling control device is equipped with a computing chip, which calculates the ideal feed speed or the ideal grinding disc speed according to the ideal nonlinear constraint based on the data collected by the operating parameter monitoring unit and the change rate of the grinding roller-liner gap over time; controls the actions of the feed speed regulating mechanism and the grinding disc speed regulating mechanism through a PID controller to achieve coordinated optimization control of the feed speed and the grinding disc speed; Ventilation optimization equipment, including wind pressure sensor, wind speed sensor, wind duct diameter measuring instrument and temperature sensor; wind pressure sensor measures wind pressure field, wind speed sensor obtains wind speed field, wind duct diameter measuring instrument monitors wind duct diameter in real time, and temperature sensor is used to measure ambient temperature and then calculate air density; The ventilation optimization device has the ventilation optimization model built in to calculate the current actual ventilation air volume; the calculation result is compared with the preset ideal air volume, and according to the difference, a command is issued to the damper opening adjustment mechanism through the PID controller to adjust the damper opening; Digital twin architecture equipment, which includes a multi-spectral CCD sensor array, including near-infrared band sensors, terahertz band sensors and ultraviolet band sensors; the near-infrared band sensor is used to measure the moisture distribution of coal powder, the terahertz band sensor detects micro-cracks on the surface of the grinding roller, and the ultraviolet band sensor monitors the combustion characteristics of coal powder; The digital twin architecture device also includes a data fusion device for processing multi-source heterogeneous data of multi-physics field coupling modeling and PID control using tensor decomposition technology; it also includes an autoencoder for online identification and updating of geometric modeling, multi-physics field coupling calculation, ventilation optimization model and PID control model parameters.

[0011] Compared with the prior art, the beneficial effects of this application are: This application constructs a parameterized model including the grinding roller-liner gap and coal particle distribution based on coal quality characteristics, which can accurately determine the dynamic value of the gap; after comparing with the rated gap, the grinding roller and liner position are adjusted in time, and the changes of grinding roller stress and coal particle distribution over time are fully considered, so that the grinding parts are always in the best matching state. Compared with the lack of precise control in the prior art, the grinding effect is greatly improved. The present application uses multi-physics field coupling calculation to establish an ideal nonlinear constraint relationship between the feed speed and the grinding disc speed; through this relationship, the ideal values ​​of the two can be calculated and adjusted according to the actual operation conditions, thereby achieving the coordinated optimization of the feed speed and the grinding disc speed, changing the drawbacks of the prior art that relies on experience adjustment, so that the coal mill can process coal more efficiently during the grinding process, thereby improving the output of the coal mill; This application constructs a ventilation optimization model, comprehensively calculates the actual ventilation air volume by combining multiple factors, and adjusts the air door opening by comparing it with the preset ideal air volume, and establishes a quantitative correlation with the coal powder suspension speed; this optimization enables the ventilation system to better adapt to the real-time operating conditions of the coal mill, ensuring that the coal powder is fully suspended and transported. Compared with existing ventilation control methods, it effectively improves the overall operating efficiency and output of the coal mill; A digital twin architecture is built, multi-spectral sensing is used to collect multi-faceted data, tensor decomposition technology is used to process multi-source heterogeneous data, and online parameter identification is realized based on variational autoencoders; this enables the model to reflect the actual operating status of the coal mill in real time, adjust and optimize the model parameters in a timely manner, and ensure the continuous and effective operation of the entire plan to improve the output of the coal mill, thus overcoming the problem of disconnection between the model and the actual operating status in the existing technology.

[0012] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0013] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] 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: Figure 1 It is a flow chart of a method for improving the output of a coal mill provided by an embodiment of the present invention; Figure 2 It is a structural schematic diagram of a device for improving the output of a coal mill provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0015] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0016] Embodiment 1: The embodiment of the present invention provides a method for improving the output of a coal mill. Figure 1 ,include: Step 1: Based on the coal quality characteristics, the internal geometry of the mill is dynamically modeled, a parametric model including the roller-liner gap and coal particle distribution is constructed, the difference between the roller-liner gap and the set gap is determined, and the positions of the roller and liner are adjusted accordingly; Step 2: Using multi-physics field coupling calculation, determine the coordinated optimization relationship between the feed speed and the grinding disc speed, establish an ideal nonlinear constraint between the two, substitute the feed speed or the grinding disc speed into the ideal nonlinear constraint, and determine the ideal grinding disc speed or the ideal feed speed; Step 3: Construct a ventilation optimization model, correct the ventilation air volume based on the air field information, obtain the actual ventilation air volume, and establish a quantitative relationship between it and the coal powder suspension velocity; compare the current actual ventilation air volume with the preset ideal air volume, and adjust the air door opening accordingly; Step 4: Use PID controller to control mill parameters; Step 5: Build a digital twin architecture and update the model parameters of the above steps in real time through multispectral sensing and data fusion technology.

[0017] It should be noted that this embodiment constructs a parameterized model based on the coal quality characteristics, adjusts the position of the grinding roller and liner in real time, optimizes the grinding roller-liner gap, adapts to different types of coal, and improves the grinding efficiency. Determine the ideal nonlinear constraints of the feed speed and the grinding disc speed to achieve coordinated optimization of the two, avoid over-grinding or under-grinding, and improve the processing capacity of the coal mill. Construct a ventilation optimization model to accurately adjust the ventilation air volume to ensure effective suspension and transportation of coal powder, prevent blockage and accumulation, and improve the operating stability of the coal mill. A PID controller is used to achieve closed-loop control of the coal mill operating parameters. Combined with the digital twin architecture and multi-spectral sensing technology, the model parameters are updated in real time to optimize the operating status. Comprehensively optimize the grinding, ventilation and control systems of the coal mill, significantly improve the output, meet production needs, enhance operational stability, reduce failure rates, optimize operating parameters, reduce energy consumption and equipment wear, extend equipment life, reduce maintenance costs, and improve economic benefits.

[0018] In order to further optimize the above embodiment, in step 1, the parameterized model is used to determine the grinding roller-liner gap, specifically: ； in, is the roller-liner gap, is the number of grinding rollers; It is the stress distribution function of the grinding roller surface, which reflects the stress distribution of the grinding roller surface and is determined based on the grinding roller model or experiment; is the coal particle size distribution matrix, which is used to quantify the distribution characteristics of coal particles; is the axial coordinate of the grinding roller surface, that is, the stress distribution function of the grinding roller surface Variable parameters; is a time variable; the grinding roller-liner gap It is used to reflect the dynamic value of the roller-liner gap considering the roller stress distribution and coal particle distribution changing with time; Wherein, the coal particle size distribution matrix satisfies: ； in, It represents the proportion of particles in the jth particle size interval in the i-th grinding roller area, and m is the particle size classification number; this matrix is ​​used to reflect the distribution ratio of coal particles in different particle size intervals in different grinding roller areas; Get the rated clearance , calculate the roller-liner gap With rated clearance The position of the grinding roller and lining plate is adjusted based on the difference.

[0019] It should be noted that this embodiment determines the roller surface stress distribution function based on the roller model or experiment, and combines the coal particle size distribution matrix to construct a parameterized model to calculate the dynamic value of the roller-liner gap. This value comprehensively considers the changes in roller stress and coal particle distribution over time. The difference is obtained by comparing it with the rated gap, and accurate adjustment is made based on the difference.

[0020] In order to further optimize the above embodiment, in step 2, the coordinated optimization relationship between the feed speed and the grinding disc speed is determined, and an ideal nonlinear constraint between the two is established. The ideal nonlinear constraint between the two is: ; in, and is the inherent constant of the device; is the coal density; The real-time power of the motor; is the rate of change of the gap between the grinding roller and the liner over time; this formula is used to reflect the dynamic relationship between the rate of change of the feed speed and the grinding disc speed and the change of the gap between the grinding roller and the liner, and then determine the feed speed With grinding disc speed Ideal nonlinear constraints; The current feed speed Or grinding disc speed Substituting into the formula, the ideal grinding disc speed is calculated Or ideal feed rate ; Based on ideal grinding disc speed Or ideal feed rate Adjust the grinding disc speed or feed speed accordingly.

[0021] It should be noted that this nonlinear constraint establishes the connection between the feed speed change rate and the grinding disc speed and the grinding roller-liner gap change by introducing key parameters such as the inherent constant of the equipment, coal density, real-time motor power, and the time change rate of the grinding roller-liner gap. The complex relationship between them is quantified using mathematical forms such as the hyperbolic tangent function, thereby obtaining the ideal nonlinear constraints of the feed speed and the grinding disc speed, and achieving the coordinated optimization of the two.

[0022] In order to further optimize the above embodiment, in step three, the ventilation optimization model is: ； in, is the diameter of the air duct; is the air density; is the wind pressure field; is the axial coordinate; Represents the rate of change of wind pressure field along the axial direction; is the air dynamic viscosity; is the wind speed field; Representing the velocity field The Laplace operator of is the Reynolds number, and ; Income The current actual ventilation air volume corrected based on the air duct characteristics, air physical properties, wind pressure and wind speed factors is compared with the preset ideal air volume and the damper opening is adjusted accordingly.

[0023] It should be noted that the ventilation optimization model combines many factors to accurately calculate the actual ventilation air volume. The diameter of the air duct determines the ventilation cross-sectional area and affects the air volume; air density and dynamic viscosity are inherent physical properties of air and participate in the air volume calculation. The axial change rate of the wind pressure field, the wind speed field and its Laplace operator reflect the airflow state. The Reynolds number integrates air density, wind speed, duct diameter and dynamic viscosity to reflect the airflow characteristics. The actual air volume is calculated by combining these factors, and the damper opening is adjusted after comparison with the ideal air volume to achieve ventilation system optimization.

[0024] In order to further optimize the above embodiment, in step 4, the control law of the PID controller is: ； in, The load deviation corresponds to adjusting the position of the grinding roller liner, adjusting the grinding disc speed or the feed speed, and adjusting the air door opening. , , They are proportional, integral, and differential coefficients, respectively, determined based on experience or experiment; is the controller output; It should be noted that the corresponding adjustment of the position of the grinding roller liner, the grinding disc rotation speed or the feed speed, and the air door opening are achieved by the PID controller.

[0025] In order to further optimize the above embodiment, in step 5, the digital twin architecture includes: The physical entity layer deploys a multi-spectral CCD sensor array, which includes a near-infrared band sensor for measuring the moisture distribution of coal powder, a terahertz band sensor for detecting micro-cracks on the surface of the grinding roller, and an ultraviolet band sensor for monitoring the combustion characteristics of coal powder; The data fusion layer uses tensor decomposition technology to process multi-source heterogeneous data for multi-physics field coupling modeling and PID control; The model update layer implements online parameter identification based on the variational autoencoder to ensure the consistency between the model and the actual operating status.

[0026] It should be noted that by deploying a multi-spectral CCD sensor array, the characteristics of sensors in different bands are used to achieve accurate data collection. The near-infrared band is sensitive to moisture and can effectively measure the moisture distribution of coal powder; terahertz waves can penetrate materials of a certain thickness and are used to detect microcracks on the surface of the grinding roller; the ultraviolet band is suitable for monitoring the combustion characteristics of coal powder and obtaining real-time physical data of the coal mill operation from multiple dimensions. The tensor decomposition technology is used to extract the key features and laws of the multi-source heterogeneous data generated in the multi-physics field coupling modeling and PID control process according to specific mathematical decomposition rules, and the complex data is converted into a form that is easier to process and analyze, eliminating redundancy and conflict between data, and providing high-quality data support for subsequent model updates. Based on the variational autoencoder, the input data is encoded and decoded by constructing an autoencoder neural network structure. Data features are extracted during the encoding process, and data is reconstructed during decoding. By comparing the difference between the reconstructed data and the original data, the parameters of the encoder and decoder are continuously optimized, thereby realizing the online identification of the model parameters, so that the model can follow the actual operating state of the coal mill in real time and maintain a high degree of consistency.

[0027] Embodiment 2: The embodiment of the present invention provides a device for improving the output of a coal mill. Figure 2 ,include: The geometric modeling and adjustment equipment includes a stress sensor and a multi-spectral particle analyzer; the stress sensor is installed on the surface of the grinding roller to collect the surface stress data of the grinding roller in real time and determine the stress distribution function of the grinding roller surface; the multi-spectral particle analyzer monitors the coal particles in real time to obtain the coal particle size distribution data, and then constructs the coal particle size distribution matrix; The geometric modeling and adjustment device has a built-in microprocessor, which calculates the roller-liner gap through the parameterized model according to the data transmitted by the stress and particle distribution monitoring unit; compares the calculated gap value with the rated gap to obtain the difference; and sends a control instruction to the roller and liner position adjustment mechanism through the PID controller according to the difference to adjust the position of the roller and liner; Multi-physics field coupling control equipment, which consists of a speed sensor, a power sensor and a density sensor; the speed sensor is used to measure the grinding disc speed, the power sensor monitors the real-time power of the motor, and the density sensor detects the coal density; The multi-physical field coupling control device is equipped with a computing chip, which calculates the ideal feed speed or the ideal grinding disc speed according to the ideal nonlinear constraint based on the data collected by the operating parameter monitoring unit and the change rate of the grinding roller-liner gap over time; controls the actions of the feed speed regulating mechanism and the grinding disc speed regulating mechanism through a PID controller to achieve coordinated optimization control of the feed speed and the grinding disc speed; Ventilation optimization equipment, including wind pressure sensor, wind speed sensor, wind duct diameter measuring instrument and temperature sensor; wind pressure sensor measures wind pressure field, wind speed sensor obtains wind speed field, wind duct diameter measuring instrument monitors wind duct diameter in real time, and temperature sensor is used to measure ambient temperature and then calculate air density; The ventilation optimization device has the ventilation optimization model built in to calculate the current actual ventilation air volume; the calculation result is compared with the preset ideal air volume, and according to the difference, a command is issued to the damper opening adjustment mechanism through the PID controller to adjust the damper opening; Digital twin architecture equipment, which includes a multi-spectral CCD sensor array, including near-infrared band sensors, terahertz band sensors and ultraviolet band sensors; the near-infrared band sensor is used to measure the moisture distribution of coal powder, the terahertz band sensor detects micro-cracks on the surface of the grinding roller, and the ultraviolet band sensor monitors the combustion characteristics of coal powder; The digital twin architecture device also includes a data fusion device for processing multi-source heterogeneous data of multi-physics field coupling modeling and PID control using tensor decomposition technology; it also includes an autoencoder for online identification and updating of geometric modeling, multi-physics field coupling calculation, ventilation optimization model and PID control model parameters.

[0028] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for increasing the output of a coal mill, characterized in that: include: Step 1: Based on the coal quality characteristics, the internal geometry of the mill is dynamically modeled, a parametric model including the roller-liner gap and coal particle distribution is constructed, the difference between the roller-liner gap and the set gap is determined, and the positions of the roller and liner are adjusted accordingly; Step 2: Using multi-physics field coupling calculation, determine the coordinated optimization relationship between the feed speed and the grinding disc speed, establish an ideal nonlinear constraint between the two, substitute the feed speed or the grinding disc speed into the ideal nonlinear constraint, and determine the ideal grinding disc speed or the ideal feed speed; Step 3: Construct a ventilation optimization model, correct the ventilation air volume based on the air field information, obtain the actual ventilation air volume, and establish a quantitative relationship between it and the coal powder suspension velocity; compare the current actual ventilation air volume with the preset ideal air volume, and adjust the air door opening accordingly; Step 4: Use PID controller to control mill parameters; Step 5: Build a digital twin architecture and update the model parameters of the above steps in real time through multispectral sensing and data fusion technology.

2. A method for increasing the output of a coal mill according to claim 1, characterized in that: In step 1, the parameterized model is used to determine the roller-liner gap, specifically: ； in, is the roller-liner gap, is the number of grinding rollers; It is the stress distribution function of the grinding roller surface, which reflects the stress distribution of the grinding roller surface and is determined based on the grinding roller model or experiment; is the coal particle size distribution matrix, which is used to quantify the distribution characteristics of coal particles; is the axial coordinate of the grinding roller surface, that is, the stress distribution function of the grinding roller surface Variable parameters; is a time variable; the grinding roller-liner gap It is used to reflect the dynamic value of the roller-liner gap considering the roller stress distribution and coal particle distribution changing with time; Wherein, the coal particle size distribution matrix satisfies: ； in, It represents the proportion of particles in the jth particle size interval in the i-th grinding roller area, and m is the particle size classification number; this matrix is ​​used to reflect the distribution ratio of coal particles in different particle size intervals in different grinding roller areas; Get the rated clearance , calculate the roller-liner gap With rated clearance The position of the grinding roller and lining plate is adjusted based on the difference.

3. A method for improving coal mill output according to claim 1, characterized in that: In step 2, the coordinated optimization relationship between the feed speed and the grinding disc speed is determined, and an ideal nonlinear constraint between the two is established. The ideal nonlinear constraint between the two is: ； in, and is the inherent constant of the device; is the coal density; The real-time power of the motor; is the rate of change of the gap between the grinding roller and the liner over time; this formula is used to reflect the dynamic relationship between the rate of change of the feed speed and the grinding disc speed and the change of the gap between the grinding roller and the liner, and then determine the feed speed With grinding disc speed Ideal nonlinear constraints; The current feed speed Or grinding disc speed Substituting into the formula, the ideal grinding disc speed is calculated Or ideal feed rate ; Based on ideal grinding disc speed Or ideal feed rate Adjust the grinding disc speed or feed speed accordingly.

4. A method for increasing the output of a coal mill according to claim 3, characterized in that: In step three, the ventilation optimization model is: ； in, is the diameter of the air duct; is the air density; is the wind pressure field; is the axial coordinate; Represents the rate of change of wind pressure field along the axial direction; is the air dynamic viscosity; is the wind speed field; Representing the velocity field The Laplace operator of is the Reynolds number, and ; Income The current actual ventilation air volume corrected based on the air duct characteristics, air physical properties, wind pressure and wind speed factors is compared with the preset ideal air volume and the damper opening is adjusted accordingly.

5. A method for increasing the output of a coal mill according to claim 4, characterized in that: In step 4, the control law of the PID controller is: ； in, The load deviation corresponds to adjusting the position of the grinding roller liner, adjusting the grinding disc speed or the feed speed, and adjusting the air door opening. , , They are proportional, integral, and differential coefficients, respectively, determined based on experience or experiment; is the controller output; The corresponding adjustment of the position of the grinding roller lining, the adjustment of the grinding disc speed or the feed speed, and the adjustment of the air door opening are achieved by the PID controller.

6. A method for increasing the output of a coal mill according to claim 5, characterized in that: In step five, the digital twin architecture includes: The physical entity layer deploys a multi-spectral CCD sensor array, which includes a near-infrared band sensor for measuring the moisture distribution of coal powder, a terahertz band sensor for detecting micro-cracks on the surface of the grinding roller, and an ultraviolet band sensor for monitoring the combustion characteristics of coal powder; The data fusion layer uses tensor decomposition technology to process multi-source heterogeneous data for multi-physics field coupling modeling and PID control; The model update layer implements online parameter identification based on the variational autoencoder to ensure the consistency between the model and the actual operating status.

7. A device for improving the output of a coal mill, based on the method of claims 1-6, characterized in that: include: a geometric modeling adjustment device, which includes a stress sensor and a multi-spectral particle analyzer; The stress sensor is installed on the surface of the grinding roller to collect the surface stress data of the grinding roller in real time and determine the stress distribution function of the grinding roller surface; the multi-spectral particle analyzer monitors the coal particles in real time, obtains the coal particle size distribution data, and then constructs the coal particle size distribution matrix; The geometric modeling and adjustment device has a built-in microprocessor, which calculates the roller-liner gap through the parameterized model according to the data transmitted by the stress and particle distribution monitoring unit; compares the calculated gap value with the rated gap to obtain the difference; and sends a control instruction to the roller and liner position adjustment mechanism through the PID controller according to the difference to adjust the position of the roller and liner; Multi-physics field coupling control equipment, which consists of a speed sensor, a power sensor and a density sensor; the speed sensor is used to measure the grinding disc speed, the power sensor monitors the real-time power of the motor, and the density sensor detects the coal density; The multi-physical field coupling control device is equipped with a computing chip, which calculates the ideal feed speed or the ideal grinding disc speed according to the ideal nonlinear constraint based on the data collected by the operating parameter monitoring unit and the change rate of the grinding roller-liner gap over time; controls the actions of the feed speed regulating mechanism and the grinding disc speed regulating mechanism through a PID controller to achieve coordinated optimization control of the feed speed and the grinding disc speed; Ventilation optimization equipment, including wind pressure sensor, wind speed sensor, wind duct diameter measuring instrument and temperature sensor; wind pressure sensor measures wind pressure field, wind speed sensor obtains wind speed field, wind duct diameter measuring instrument monitors wind duct diameter in real time, and temperature sensor is used to measure ambient temperature and then calculate air density; The ventilation optimization device has the ventilation optimization model built in to calculate the current actual ventilation air volume; the calculation result is compared with the preset ideal air volume, and according to the difference, a command is issued to the damper opening adjustment mechanism through the PID controller to adjust the damper opening; Digital twin architecture equipment, which includes a multi-spectral CCD sensor array, including near-infrared band sensors, terahertz band sensors and ultraviolet band sensors; the near-infrared band sensor is used to measure the moisture distribution of coal powder, the terahertz band sensor detects micro-cracks on the surface of the grinding roller, and the ultraviolet band sensor monitors the combustion characteristics of coal powder; The digital twin architecture device also includes a data fusion device for processing multi-source heterogeneous data of multi-physics field coupling modeling and PID control using tensor decomposition technology; it also includes an autoencoder for online identification and updating of geometric modeling, multi-physics field coupling calculation, ventilation optimization model and PID control model parameters.

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