High position front caving control method

Abstract

The present application relates to the technical field of coal mining, and particularly relates to a high-position front top coal caving control method, which comprises the following steps: S1, when the advancing distance of a coal mining machine reaches the distance between the hydraulic support and the coal mining machine, the telescopic beam and the support plate are synchronously contracted to provide a distance for the support moving operation; S2, the stand column is controlled to be depressurized to the pressure requirement of the support moving; S3, the push-moving oil cylinder is controlled to be contracted to drive the hydraulic support to move forward; S4, the stand column is controlled to be pressurized to the initial support force requirement, and the balance oil cylinder is differentially controlled; S5, the balance oil cylinder is controlled to be contracted to make the front beam lie down to form a caving window, the size of the caving window is controlled by monitoring the inclination angle of the front beam through the front beam inclination sensor, and the top coal is realized to slide to the front scraper conveyor; and S6, the telescopic beam and the support plate are controlled to be extended, the caving is stopped, and the supporting state is restored. The method effectively solves the technical problems of the coupling of the mining and caving timing, the complexity of the equipment coordination, and the insufficient control precision, and improves the automation level and the mining efficiency of the top coal caving mining.

Description

Technical Field

[0001] This invention relates to the field of coal mining technology, and in particular to a method for controlling top coal caving at high positions. Background Technology

[0002] Top coal caving is a core technology for efficient mining of thick coal seams. Based on the location of the top coal caving, it can be categorized into high-level top coal caving, mid-level top coal caving, and low-level top coal caving. Current technologies primarily employ low-level top coal caving, which involves controlling a sequence of actions such as the retraction, extension, swing, retraction, and extension of the hydraulic support tail beam insert plate to achieve the caving and recovery of the top coal.

[0003] Existing top coal caving technology is divided into two categories based on the timing of coal mining and coal release: shutdown coal release and on-the-fly coal release. Shutdown coal release refers to the coal mining machine stopping after completing one or more cuts, while the hydraulic supports sequentially release coal according to a preset program. This method typically takes 2-3 times longer than the cutting time, requiring the coal mining machine to wait for an extended period, making parallel mining and coal release operations impossible. On-the-fly coal release primarily uses a follow-the-machine coal release mode, performing coal release operations synchronously with the coal mining machine's advance. Methods include follow-the-machine coal release, memory-based coal release, and planned coal release.

[0004] The existing low-position top coal caving technology has the following technical defects: The mining and coal release sequence is highly coupled, and equipment coordination is complex. In the existing process, the hydraulic support relocation must be completed before coal release. The timing requirements for the actions of the front conveyor, hydraulic support, and rear conveyor are strict. Any deviation in the timing of any link may lead to equipment interference or failure of top coal recovery. In particular, spatial interference between the tail beam insert plate and the rear conveyor occurs frequently, affecting equipment safety and production continuity.

[0005] Coal mining efficiency is severely constrained by the coal release process. Because the coal release time far exceeds the coal cutting time, the mining machine must frequently wait for the release operation to complete, limiting the overall advance speed of the working face. Even with the use of a coal release-as-you-go mining process, a clear time dependency exists between coal mining and release, making it difficult to achieve truly parallel and efficient operations.

[0006] The control precision is insufficient and the adaptability is poor. Existing top coal caving control mainly relies on the operator's experience and simple program control, lacking the ability to accurately monitor and dynamically adjust the coal caving process. Faced with different coal quality characteristics and changes in geological conditions, the control strategy is not adaptable enough, and the top coal recovery rate and coal caving safety are difficult to guarantee. Summary of the Invention

[0007] This invention provides a high-level front-end top coal caving control method, which can effectively solve the technical problems of mining and caving sequence coupling, complex equipment coordination, and insufficient control accuracy in the prior art, and improve the automation level and mining efficiency of top coal caving mining.

[0008] This invention provides a high-level front-end top coal caving control method. By controlling the high-level front-end top coal caving hydraulic support to continuously execute the following steps during normal coal cutting by the coal mining machine, coordinated coal caving operation is achieved: S1. When the coal mining machine advances to the distance between the hydraulic support and the machine, the telescopic beam and side guard plate are controlled to retract synchronously to provide distance for the support shifting operation; S2. The pressure of the column is controlled to decrease to the required pressure for support shifting; S3. The pushing cylinder is controlled to retract, driving the hydraulic support forward; S4. The pressure of the column is controlled to increase to the initial support force requirement, while differential control is applied to the balance cylinder; S5. The balance cylinder is controlled to retract, causing the front beam to tilt downwards to form a coal caving window. The size of the coal caving window is controlled by monitoring the pitch angle of the front beam using a front beam tilt sensor, allowing the top coal to slide down to the front scraper conveyor; S6. The telescopic beam and side guard plate are controlled to extend, stopping coal caving and restoring the support state.

[0009] In one possible implementation, step S5 uses sensor feedback to control the size of the coal discharge window, including: monitoring the attitude parameters of the hydraulic support through sensors; calculating control commands based on the attitude parameters; and controlling the action of the balance cylinder to adjust the coal discharge window.

[0010] In one possible implementation, a PID control algorithm integrating the front beam tilt angle sensor and the shield beam tilt angle sensor is used to adjust the coal discharge window. Specifically, this includes: calculating a fusion error term based on the front beam pitch angle α detected by the front beam tilt angle sensor and the shield beam tilt angle β detected by the shield beam tilt angle sensor; inputting the fusion error term into the PID control algorithm to generate the control output of the balancing cylinder; and controlling the coordinated action of the balancing cylinder and the column based on the control output.

[0011] In one possible implementation, the calculation of the fusion error term includes: Calculate the pitch angle deviation of the front beam: ; Calculate the deviation of the shield beam's tilt angle: ; Calculate the fusion error term: ; in, , The target angles for the front beam and the shield beam are pre-set based on coal discharge experience. , Let be the actual angles at time k. , These are the weighting coefficients.

[0012] In one possible implementation, the calculation formula for the PID control algorithm is: ; Where u_k is the control output of the balancing cylinder at time k. For proportional gain, The integral coefficient is... These are the differential coefficients. The sampling period.

[0013] One possible implementation also includes a cross-coupling compensation step: ; Where u'_k is the compensated control command for the balance cylinder. is the coupling coefficient, used to compensate for the dynamic coupling relationship between the pitch of the front beam and the tilt of the shield beam.

[0014] In one possible implementation, the weighting coefficient is adjusted based on the top coal flow characteristics: for top coal that is soft and has good flowability, the weighting coefficient is increased. Reduce weighting coefficient Prioritize ensuring the front beam pitch angle is close to the target value; for top coal with hard quality and poor fluidity, increase the weighting coefficient. Reduce weighting coefficient Increase the stability weight of the protective beam.

[0015] In one possible implementation, step S6 further includes: controlling the balancing cylinder through numerical feedback from the front beam tilt angle sensor to keep the front beam in a horizontal state; calculating the support height using the shield beam tilt angle sensor and controlling the column to adjust to the mining height that meets the mining requirements.

[0016] One possible implementation also includes a safety protection mechanism: if the pitch angle value of the front beam detected by the current beam tilt sensor exceeds a safety threshold... At that time, the protection mechanism is forcibly triggered, stopping the coal release operation.

[0017] In one possible implementation, multiple hydraulic supports execute steps S1 to S6 sequentially according to a scheduling method to achieve coordinated advancement of coal cutting by the coal mining machine and coal release by the supports.

[0018] This invention provides a high-position front-end top coal caving control method that integrates the hydraulic support's shifting action with the coal caving action into a continuously executed control sequence. This allows the coal mining machine to trigger the hydraulic support to synchronously complete the following and coal caving operations during continuous advancement. When the coal mining machine's advancement distance reaches the following distance, the hydraulic support executes the complete process of retracting the telescopic beam, lowering the column, pushing, raising the column, caving coal, and extending the telescopic beam, without waiting for the coal mining machine to stop or for confirmation of other equipment status. This eliminates the time dependence between coal mining and coal caving in traditional processes. The high-position front-end coal caving layout uses the telescopic beam and side guard plate contraction combined with the front beam lying down to form a coal caving channel, allowing the top coal to slide directly onto the front scraper conveyor, avoiding the rear equipment area. This solves the spatial interference problem between the tail beam insert plate and the rear conveyor in traditional low-position coal caving, enabling the hydraulic support to independently complete the shifting and coal caving process. The established closed-loop control system based on the front beam tilt angle sensor dynamically adjusts the contraction of the balancing cylinder by real-time monitoring of the front beam pitch angle, precisely controlling the size of the coal release window. This adapts to changes in top coal flowability under different geological conditions, ensuring the continuity and controllability of the coal release process. The differential control of the balancing cylinder maintains appropriate pre-pressure and responsiveness during the column pressurization process, preventing excessive compaction of the front beam by the roof, providing sufficient driving force and rapid response for the coal release action, shortening the transition time from support shifting to coal release, and achieving coordinated operation between support and coal release functions. This effectively solves the technical problems of coupled mining and release sequences, complex equipment coordination, and insufficient control precision in existing technologies, improving the automation level and mining efficiency of top coal caving mining. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a flowchart of a high-level front-end top coal caving control method provided by the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of a high-position front-mounted top coal caving hydraulic support provided by the present invention.

[0022] Figure 3 This is a schematic diagram of the detection angle of a high-position front-mounted top coal caving hydraulic support provided by the present invention.

[0023] Figure label: 1. Side guard plate; 2. Telescopic beam; 3. Front beam; 4. Protective beam; 5. Balance cylinder; 6. Column; 7. Push cylinder; 8. Front beam tilt sensor; 9. Protective beam tilt sensor. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0025] The following is combined with Figure 1 This invention describes a high-position front-end top coal caving control method, which achieves coordinated coal caving operation by controlling the high-position front-end top coal caving hydraulic support to continuously execute the following steps during the normal coal cutting process of the coal mining machine: S1. When the coal mining machine advances to the distance between the hydraulic support and the machine, control the telescopic beam 2 and the side guard plate 1 to retract synchronously to provide distance for the support moving operation. S2, Control column 6 to reduce pressure to the required moving pressure; S3. Control the retraction of the push cylinder 7 to drive the hydraulic support to move forward; S4. Control the column 6 to increase the pressure to meet the initial support force requirement, and at the same time perform differential control on the balance cylinder 5; S5. Control the retraction of the balance cylinder 5 to make the front beam 3 tilt downward to form a coal discharge window. The pitch angle of the front beam 3 is monitored by the front beam tilt angle sensor 8 to control the size of the coal discharge window, so that the top coal slides down to the front scraper conveyor. S6. Control the extension beam 2 and the side plate 1 to extend, stop coal feeding and restore the support status.

[0026] In this invention, the hydraulic support's moving action and coal release action are integrated into a continuously executed control sequence, completely changing the traditional operation mode where coal mining and coal release are executed separately. When the coal mining machine advances to the following distance, the hydraulic support immediately executes the continuous action process of retracting the telescopic beam 2 → lowering the column → pushing → raising the column → releasing coal → extending the telescopic beam 2. The entire process does not require waiting for the coal mining machine to stop or for other equipment status confirmations. Compared to the traditional process that requires stopping the machine after completing a certain coal cutting progress to execute a centralized coal release procedure, this invention enables the coal mining machine to advance continuously according to optimal parameters, no longer constrained by the time of the coal release stage. This parallel operation mode transforms the original intermittent cycle of coal cutting-stopping-coal release-advancement into a continuous and coordinated operation of coal mining and coal release, significantly improving the overall advancement efficiency of the working face. At the same time, continuous operation of the coal mining machine avoids equipment impact and increased energy consumption caused by frequent start-stop operations, extending the service life of the equipment.

[0027] This technical solution fundamentally solves the multi-equipment coordination problem in traditional low-level coal feeding by adopting a high-level front coal feeding spatial layout. Traditional processes require strict timing control of the hydraulic support, front conveyor, and rear conveyor. When the tail beam insert plate operates above the rear conveyor, spatial interference can easily occur, leading to equipment damage. This invention, through the retraction of the telescopic beam 2 and the side guard plate 1, combined with the downward movement of the front beam 3, forms a coal feeding channel, allowing the top coal to slide directly onto the front scraper conveyor. The entire coal feeding path completely avoids the rear equipment area. This layout eliminates spatial conflicts between equipment, enabling the hydraulic support to independently complete the entire coal feeding process, simplifying the complexity of the control system, improving operational reliability and safety, and reducing equipment investment and maintenance costs because no rear conveying equipment is required.

[0028] The closed-loop control system based on the front beam tilt sensor 8 established in this invention realizes intelligent management of the coal discharge process. The system precisely controls the size of the coal discharge window by dynamically adjusting the contraction amount of the balancing cylinder 5 based on real-time monitoring of the pitch angle of the front beam 3. When insufficient angle is detected, the contraction amount is automatically increased to widen the opening; when the risk of excessive coal discharge is detected, the contraction amount is adjusted in a timely manner to control the flow rate. This sensor feedback control can adapt to changes in top coal flowability under different geological conditions, effectively addressing the influence of factors such as coal hardness and moisture content, ensuring the continuity and controllability of the coal discharge process, avoiding the problems of insufficient or excessive coal discharge caused by traditional experience-based operations, and significantly improving coal discharge quality and recovery rate.

[0029] This technical solution establishes a coordination mechanism between support and coal discharge functions through differential control of the balancing cylinder 5. During the pressurization process of the column 6, differential control of the balancing cylinder 5 ensures it maintains appropriate preload and responsiveness under support load, preventing excessive compaction of the front beam 3 by the roof plate from affecting subsequent coal discharge operations. Differential control provides sufficient driving force and rapid response for coal discharge initiation, significantly shortening the transition time from support shifting to coal discharge, and improving the continuity of the control process and operational efficiency. Simultaneously, the differential parameters can be adjusted according to different support pressure requirements, ensuring both the safety support requirements of the support structure and creating optimal execution conditions for coal discharge operations, thus achieving an organic unity between structural support and coal recovery functions.

[0030] Specifically, in step S1, the telescopic beam 2 and the side guard plate 1 retract synchronously to reserve space for the support relocation operation, avoiding collisions and interference during the relocation process; in step S2, the pressure of the column 6 is reduced to the required support relocation pressure to ensure that the pushing cylinder 7 can smoothly drive the support to move; in step S3, the retraction of the pushing cylinder 7 realizes the forward positioning of the support; in step S4, the pressure of the column 6 is increased to meet the initial support force requirement, restoring the support's load-bearing capacity, while differential control of the balance cylinder 5 is performed to prepare for subsequent coal release; in step S5, the balance cylinder 5 controls the front beam 3 to tilt downward to form a coal release window, and the front beam tilt angle sensor 8 monitors the pitch angle change in real time, adjusting the size of the coal release window according to the angle feedback to achieve controllable sliding of top coal; in step S6, the telescopic beam 2 and the side guard plate 1 extend to restore the normal support state, and the coal release operation stops.

[0031] In one specific embodiment, when the working face advances to a top-coal caving face with a coal seam thickness of 8 meters, the coal mining machine cuts out the lower 4-meter-thick coal seam, and the remaining 4-meter-thick top coal needs to be recovered through the top-coal caving process. With this control method, the hydraulic support can maintain synchronization with the coal mining machine's 0.8-meter following distance. Whenever the coal mining machine advances 0.8 meters, the support automatically performs a complete following-machine coal caving cycle, ensuring timely recovery of the top coal and avoiding the risk of roof collapse caused by prolonged top coal suspension.

[0032] In some embodiments, step S5 uses sensor feedback to control the size of the coal discharge window, including: monitoring the attitude parameters of the hydraulic support through sensors; calculating control commands based on the attitude parameters; and controlling the action of the balance cylinder 5 to adjust the coal discharge window.

[0033] In this invention, a sensor feedback control method is adopted based on the coal discharge window control in step S5. This method achieves precise automatic control of the coal discharge process by monitoring the attitude parameters of the hydraulic support, calculating control commands based on these parameters, and controlling the balance cylinder 5 to adjust the coal discharge window in a closed-loop control process. The attitude parameters monitored in real time by the sensors are processed by the control algorithm to generate corresponding control commands, driving the balance cylinder 5 to perform precise actions, thus forming a complete feedback loop from perception to execution.

[0034] Specifically, the hydraulic support posture parameters include key position information such as the pitch angle of the front beam 3 and the tilt angle of the shield beam 4. Sensors convert these physical quantities into electrical signals and input them into the control system. The control system calculates the deviation between the current state and the desired state based on the preset control algorithm and target parameters, and generates corresponding control commands. The balance cylinder 5 performs extension and retraction movements according to the control commands to adjust the pitch of the front beam 3, thereby precisely controlling the opening size of the coal discharge window.

[0035] In one specific embodiment, when the properties of the top coal change at the working face, soft top coal, with its good flowability, requires a smaller coal discharge window, while hard top coal requires a larger coal discharge window to slide smoothly. The sensor feedback control system can automatically adjust the action of the balancing cylinder 5 according to the actual changes in the support posture, adapting to the coal discharge requirements of different top coal properties, ensuring that neither too large a window causes excessive top coal to fall, nor too small a window causes top coal to become blocked and unable to be discharged.

[0036] In this embodiment of the invention, by introducing a sensor feedback control mechanism, the system can acquire accurate attitude information of the support in real time and automatically adjust according to the deviation between the actual state and the target state. Compared with experience-based operation, sensor feedback control has the advantages of fast response, high accuracy, and good repeatability, significantly improving the controllability and stability of the coal feeding process.

[0037] In some embodiments, a PID control algorithm integrating the front beam tilt angle sensor 8 and the shield beam tilt angle sensor 9 is used to adjust the coal discharge window. Specifically, this includes: calculating a fusion error term based on the pitch angle α of the front beam 3 detected by the front beam tilt angle sensor 8 and the tilt angle β of the shield beam 4 detected by the shield beam tilt angle sensor 9; inputting the fusion error term into the PID control algorithm to generate the control output of the balancing cylinder 5; and controlling the coordinated action of the balancing cylinder 5 and the column 6 based on the control output.

[0038] In this invention, a PID control algorithm integrating the front beam tilt angle sensor 8 and the shield beam tilt angle sensor 9 is used to adjust the coal discharge window. Through the fusion of information from both sensors and the combined control effect of the PID algorithm, high-precision coal discharge window control is achieved. The front beam tilt angle sensor 8 detects the pitch angle α of the front beam 3, reflecting the direct state of the coal discharge window. The shield beam tilt angle sensor 9 detects the tilt angle β of the shield beam 4, providing information on the overall stability of the support. The fusion of these two sensors forms a fusion error term, which is input into the PID control algorithm to generate the control output of the balancing cylinder 5. Precise control is achieved through the coordinated action of the balancing cylinder 5 and the column 6.

[0039] Specifically, the front beam tilt sensor 8, installed on the front beam 3, can directly measure the pitch angle of the front beam 3 relative to the horizontal plane, reflecting the actual opening degree of the coal discharge window; the shield beam tilt sensor 9, installed on the shield beam 4, measures the tilt state of the shield beam 4, reflecting the stability and working posture of the entire hydraulic support; the calculation of the fusion error term comprehensively considers the information of the two sensors, avoiding the measurement error or insufficient local information that may exist with a single sensor; the proportional term in the PID control algorithm provides fast response, the integral term eliminates steady-state error, and the derivative term provides damping effect, and the combination of the three achieves a control effect that is both fast and stable; the coordinated action of the balance cylinder 5 and the column 6 ensures that the overall stability of the support is maintained while the pitch of the front beam 3 is adjusted.

[0040] In one specific embodiment, when the pressure on the roof of the working face changes, relying solely on the front beam tilt sensor 8 may not fully reflect the true working state of the support. For example, when the roof pressure increases, the shield beam 4 may tilt. In this case, even if the angle of the front beam 3 is normal, the stability of the entire support will be affected. By adopting PID control with dual sensor fusion, the system not only focuses on the coal discharge window status of the front beam 3, but also monitors the stability of the shield beam 4, ensuring that the support maintains a good working state throughout the coal discharge process through comprehensive control.

[0041] In this embodiment of the invention, information fusion between the front beam tilt angle sensor 8 and the shield beam tilt angle sensor 9 yields more comprehensive and accurate status information than that obtained from a single sensor. The application of the PID control algorithm enables the system to possess excellent dynamic response characteristics and steady-state accuracy. Compared with single-sensor control, dual-sensor fusion control can significantly improve control accuracy and system stability, ensuring the safety and reliability of the coal discharge process.

[0042] In some embodiments, the calculation of the fusion error term includes: Calculate the pitch angle deviation of the front beam: ; Calculate the deviation of the shield beam's tilt angle: ; Calculate the fusion error term: ; in, , The target angles for the front beam and the shield beam are pre-set based on coal discharge experience. , Let be the actual angles at time k. , These are the weighting coefficients.

[0043] In this invention, a mathematical relationship model between the pitch angle deviation of the front beam 3 and the tilt angle deviation of the shield beam 4 is established through a specific calculation formula for the fusion error term, realizing the quantitative fusion processing of dual-sensor information. (Front beam 3 pitch angle deviation) and the deviation of the tilt angle of the protective beam 4 These reflect the degree of deviation of the front beam 3 and the shield beam 4 from the target state, respectively, through the weighting coefficient ω1, The weighted combination forms the fusion error term. This provides an accurate input signal for the PID control algorithm.

[0044] Specifically, from the perspective of the target , These parameters, pre-set based on coal feeding experience and operating conditions, represent the ideal working state parameters; from a practical perspective... , The current working status is reflected by real-time measurements from sensors; the angle deviation is calculated by subtracting the actual value from the target value, with positive values ​​indicating that the angle needs to be increased and negative values ​​indicating that the angle needs to be decreased; weighting coefficients... , The settings allow the system to adjust the importance of the two sensor information according to actual needs. When the front beam is larger, more attention is paid to controlling the three angles. When the angle is large, more attention is paid to the stability control of the support; the calculation of the fusion error term combines two independent angle deviations into a unified control input, which simplifies the complexity of the control algorithm.

[0045] In one specific embodiment, different combinations of weighting coefficients can be set for different coal seam conditions. In working faces with softer coal and better top coal flowability, [the following is an example of a specific weighting coefficient combination]. =0.7、 =0.3, prioritize precise control of the front beam angle 3 to prevent excessive coal outflow; in working faces with hard coal and high roof pressure, set =0.4、 =0.6, placing greater emphasis on the stability of the shield beam 4 to ensure the safety of the support. This flexible weight configuration allows the control system to adapt to different geological conditions and process requirements.

[0046] In this embodiment of the invention, the introduction of weighting coefficients enables flexible configuration of sensor information fusion, allowing for adjustments to the control strategy based on different operating conditions. The quantitative error calculation formula ensures the accuracy and repeatability of the control algorithm, offering higher reliability and consistency compared to empirical qualitative control.

[0047] In some embodiments, the calculation formula for the PID control algorithm is: ; Where u_k is the control output of the balancing cylinder at time k. For proportional gain, The integral coefficient is... These are the differential coefficients. The sampling period.

[0048] In this invention, the fused error term is converted into a specific control output for the balancing cylinder 5 through a complete mathematical expression of the PID control algorithm, thus achieving precise conversion from error signal to control action. The proportional term of the PID control algorithm... Provides control action proportional to the current error, integral term Historical errors are accumulated, and the differential term is processed. Predictive control is performed based on the trend of error change. The combination of the three control actions gives the system excellent control performance, including fast response, zero steady-state error, and strong anti-interference capabilities.

[0049] Specifically, proportional gain It determines the system's response speed. A larger value results in a faster response but may cause oscillations; it needs to be set appropriately based on system characteristics; integral coefficient Used to eliminate steady-state errors of the system, it corrects persistent deviations by accumulating historical error information; differential coefficients It provides proactive control, predicting the system's development trend based on the rate of change of error, which helps improve the system's stability and speed; sampling period It is the basic time unit of the digital control system, which affects the execution frequency and control accuracy of the control algorithm; the control output u_k directly corresponds to the action amount of the balancing cylinder 5, with a positive value indicating that the cylinder extends and a negative value indicating that the cylinder retracts.

[0050] In one specific embodiment, when the system detects that the angle of the front beam 3 deviates from the target value by 2 degrees, the proportional term immediately generates a corresponding control output to drive the balancing cylinder 5 to correct the deviation. If the deviation persists, the integral term gradually accumulates and increases the control output until the deviation is eliminated. When the system approaches the target state, the derivative term detects a decrease in the rate of change of error and provides a reverse damping effect to prevent overshoot. This triple control mechanism ensures that the system can respond quickly and converge stably to the target state.

[0051] In this embodiment of the invention, the complete PID control algorithm fully utilizes information on current error, historical error, and error change trends to achieve high-precision and high-stability control. Compared to simple control methods, PID control can effectively eliminate steady-state error, improve anti-interference capability, and ensure the accuracy and stability of coal discharge window control.

[0052] In some embodiments, a cross-coupling compensation step is also included: ; Where u'_k is the compensated control command for the balance cylinder. is the coupling coefficient, used to compensate for the dynamic coupling relationship between the pitch of the front beam and the tilt of the shield beam.

[0053] In this invention, a cross-coupling compensation mechanism is introduced through the coupling coefficient. Compensation is provided for the dynamic coupling relationship between the pitch of the front beam 3 and the tilt of the shield beam 4, effectively suppressing mutual interference in the multi-input multi-output system. The pitch movement of the front beam 3 affects the mechanical balance of the entire hydraulic support, while the tilt of the shield beam 4 also constrains the movement of the front beam 3. The cross-coupling compensation term... The product effect of the two angular deviations is taken into account, and additional compensation control is provided when both deviations exist simultaneously, thereby improving the decoupling performance of the system.

[0054] Specifically, coupling coefficient This reflects the strength of the interaction between the pitch of the front beam 3 and the tilt of the shield beam 4; its value needs to be calibrated based on the structural characteristics and operating conditions of the hydraulic support; product term This represents the interaction between two deviations. When the two deviations are in the same direction, the product is positive, providing positive compensation. When the deviations are in opposite directions, the product is negative, providing reverse compensation. The compensated control command u'_k adds a coupling compensation amount to the original PID output, enabling the control system to simultaneously take into account the front beam 3-angle control and the support stability maintenance.

[0055] In one specific embodiment, when the front beam 3 needs to pitch downwards to increase the coal discharge window, this action will shift the center of gravity of the entire support forward, potentially causing the shield beam 4 to tilt forward. Without coupling compensation, the tilt of the shield beam 4 will, in turn, affect the pitch accuracy of the front beam 3. Through a cross-coupling compensation mechanism, the system automatically considers the impact on the stability of the shield beam 4 while controlling the pitch of the front beam 3, providing corresponding compensation control to ensure that both control objectives are met.

[0056] In this embodiment of the invention, the dynamic coupling relationship between the pitch of the front beam 3 and the tilt of the shield beam 4 is effectively handled through a cross-coupling compensation mechanism, thereby improving the overall performance of the multivariable control system. Compared with separate control, cross-coupling compensation can significantly reduce mutual interference between channels, thereby improving control accuracy and system stability.

[0057] In some embodiments, the weighting coefficients are adjusted according to the top coal flow characteristics: For top coal with soft texture and good fluidity, increase the weighting coefficient. Reduce weighting coefficient Prioritize ensuring that the pitch angle of the front beam 3 is close to the target value; For top coal with hard texture and poor fluidity, increase the weighting coefficient. Reduce weighting coefficient Increase the stability weight of the protective beam 4.

[0058] In this invention, intelligent optimization of the control strategy is achieved by adaptively adjusting the weighting coefficients based on the top coal flow characteristics. This is accomplished by dynamically adjusting the weighting coefficients based on the different characteristics of the coal quality (soft vs. hard, good vs. poor flowability). and The value allows the control system to adopt the most suitable control strategy for different geological conditions. When the coal is soft, the value increases. Decrease Prioritize controlling the pitch angle of the front beam 3; increase the pitch angle when the coal is hard. Decrease Increasing the stability weight of the protective beam 4, this adaptive adjustment mechanism significantly improves the system's adaptability and robustness.

[0059] Specifically, soft, fluid top coal flows easily under relatively small external forces, making precise control of the coal discharge window crucial. Accurate 3-angle control of the front beam is needed to prevent excessive top coal outflow, which could lead to roof collapse or blockage of the scraper conveyor. Hard, poorly fluid top coal requires greater impact force to break and flow out, making the stability of the support more important. 4-angle control of the shield beam is necessary to ensure the support remains stable under the impact of top coal. The adaptive adjustment of the weighting coefficients is dynamically configured based on on-site geological exploration data and actual coal discharge results, achieving optimal matching between the control strategy and geological conditions.

[0060] In one specific embodiment, the upper part of a working face consists of soft mudstone interlayers, while the lower part consists of harder sandstone layers, resulting in significant differences in the properties of the top coal. During the working face advancement, the system automatically adjusts the weighting coefficients based on pre-set geological stratification information: setting weighting coefficients in the soft areas... =0.8、 =0.2, focus on controlling the angle of the front beam at 3 to prevent excessive coal outflow; set in hard areas =0.3、 =0.7, focusing on ensuring the stability of the support structure to resist top coal impact. This adaptive control strategy significantly improves the coal discharge efficiency and equipment safety under different geological conditions.

[0061] In this embodiment of the invention, by adaptively adjusting the weights based on the top coal flow characteristics, the system can optimize the control strategy according to different geological conditions, achieving good control performance under various operating conditions. Compared to fixed-weight control, adaptive weight adjustment can fully utilize the potential of the control system, improving top coal recovery rate and equipment adaptability.

[0062] In some embodiments, step S6 further includes: controlling the balancing cylinder 5 through numerical feedback of the front beam tilt sensor 8 to keep the front beam 3 in a horizontal state; calculating the support height using the shield beam tilt sensor 9, and controlling the column 6 to adjust to the mining height that meets the mining requirements.

[0063] In this invention, during the restoration of the support state in step S6, a function for controlling the horizontal state of the front beam 3 and adjusting the support height is added. The front beam tilt sensor 8 provides numerical feedback to control the balancing cylinder 5, ensuring the front beam 3 remains horizontal. The shield beam tilt sensor 9 calculates the support height and adjusts the column 6 to the required mining height, achieving precise restoration and adaptive adjustment of the support's working state after coal release. This refined restoration control ensures that the hydraulic support can accurately return to its standard working posture after coal release, providing reliable support conditions for the next mining cycle.

[0064] Specifically, the front beam tilt sensor 8 monitors the angle of the front beam 3 relative to the horizontal plane in real time. When the front beam 3 is detected to be tilted, the control system drives the balance cylinder 5 to make corresponding adjustments until the front beam 3 reaches a horizontal state. The measurement data of the shield beam tilt sensor 9, combined with the geometric parameters of the support, can calculate the current support height. When there is a deviation between the calculated height and the required mining height, the system controls the column 6 to adjust its height. Maintaining the horizontal state of the front beam 3 ensures good contact between the support top beam and the roof, avoiding problems such as excessive local stress or inadequate support caused by the tilt of the front beam 3. The automatic adjustment of the mining height adapts to the undulation of the roof and changes in the coal seam thickness, ensuring that the support always provides appropriate support force.

[0065] In one specific embodiment, the coal seam thickness in a certain working face varies between 3.5 and 4.2 meters, with significant roof undulations. After implementing this recovery control function, the support can automatically adjust to a mining height matching the current coal seam thickness at the end of each coal discharge, and the front beam 3 automatically returns to a horizontal state to ensure uniform contact with the roof. This adaptive adjustment avoids the tediousness and inaccuracy of manual adjustments, significantly improving support quality and work efficiency.

[0066] In this embodiment of the invention, automatic recovery control based on sensor feedback achieves precise restoration of the support's working state, eliminating the subjectivity and arbitrariness of manual operation. Front beam 3 horizontal state control and automatic mining height adjustment ensure that the support is in optimal working condition after each restoration, improving support quality and the system's automation level.

[0067] In some embodiments, a safety protection mechanism is also included: when the pitch angle value of the front beam 3 detected by the current beam tilt sensor 8 exceeds a safety threshold. At that time, the protection mechanism is forcibly triggered, stopping the coal release operation.

[0068] In this invention, a safety protection mechanism is set up so that the pitch angle value of the front beam 3 detected by the front beam tilt sensor 8 exceeds a safety threshold. A forced triggering protection mechanism stops the coal discharge operation, establishing a proactive safety protection system based on real-time monitoring. Safety threshold. Based on the design parameters of the hydraulic support, the characteristics of the top coal, and the safety operating procedures, the coal discharge process is immediately interrupted when the system detects that the angle of the front beam 3 exceeds the safe range, effectively preventing equipment damage or personnel injury caused by excessive pitching of the front beam 3.

[0069] Specifically, the front beam tilt sensor 8 continuously monitors the pitch angle change of the front beam 3, with a sufficiently high sampling frequency to ensure timely detection of anomalies; safety threshold. The setting comprehensively considers various factors such as the mechanical strength of the front beam 3, the load-bearing capacity of the hydraulic system, and the impact characteristics of the top coal. It is usually set to 80%-90% of the maximum safe pitch angle of the front beam 3. When the detection angle exceeds the threshold, the system immediately issues a stop command, the balance cylinder 5 stops moving, and may also activate an alarm device to remind the operator. The triggering of the protection mechanism is mandatory and is not affected by other control commands, ensuring that the principle of safety first is implemented.

[0070] In one specific embodiment, when a working face encounters a large, hard piece of top coal, the sudden collapse of the top coal may generate excessive impact force on the front beam 3, causing a rapid change in the pitch angle of the front beam 3. Without a safety protection mechanism, continued coal feeding may result in serious consequences such as deformation of the front beam 3, damage to the balance cylinder 5, or instability of the support. By setting a safety threshold and monitoring it in real time, the system can stop the coal feeding operation in time before the danger occurs, avoiding equipment damage and safety accidents.

[0071] In this embodiment of the invention, the sensor-based automatic safety protection mechanism has the advantages of fast response, accurate judgment, and reliable operation. Real-time monitoring and automatic protection significantly improve the inherent safety level of the system, reduce reliance on manual judgment, and provide more reliable safety assurance for downhole operations.

[0072] In some embodiments, multiple hydraulic supports execute steps S1 to S6 sequentially according to a scheduling method to achieve coordinated advancement of coal cutting by the coal mining machine and coal release by the supports.

[0073] In this invention, multiple hydraulic supports sequentially execute steps S1 to S6 according to a scheduling method to achieve coordinated advancement of coal cutting by the coal mining machine and coal release by the supports, establishing a unified scheduling and control system at the working face level. By rationally arranging the action sequence of each support, the advancement rhythm of the coal mining machine is ensured to remain coordinated with the coal release operation of the entire working face support group, forming an orderly and efficient fully mechanized mining operation mode. This coordinated control avoids mutual interference and timing chaos that may occur when each support operates independently, improving the overall advancement efficiency and safety of the working face.

[0074] Specifically, the scheduling method formulates the action plan for each support based on the advancing direction and speed of the coal mining machine. Usually, the supports are arranged to perform the coal release process in the order in which the coal mining machine passes. The execution time of steps S1 to S6 of each support needs to be staggered with the action time of adjacent supports to avoid the risk of roof instability caused by simultaneous support movement or coal release. The working face communication system is responsible for transmitting the position information of the coal mining machine and the status information of each support to ensure the real-time performance and accuracy of scheduling control. During the coordinated advancement process, each support must not only complete its own coal release task but also cooperate with the advancement rhythm of the entire working face to achieve the unity of local control and overall coordination.

[0075] In this embodiment of the invention, the coordinated movement of each support on the working face is achieved through unified scheduling and collaborative control, eliminating the arbitrariness and uncertainty of decentralized control. The collaborative propulsion mechanism ensures the spatiotemporal matching of coal cutting by the coal mining machine and coal release by the support group, significantly improving the automation level and production efficiency of the fully mechanized mining face.

[0076] like Figure 2-3 As shown, the present invention provides a high-level front-end top coal caving control system for implementing the above-mentioned method, comprising: a high-level front-end top coal caving hydraulic support, having a side guard plate 1, a telescopic beam 2, a front beam 3, a shield beam 4, a balance cylinder 5, a column 6, and a pushing cylinder 7, wherein the front beam 3 is hinged to the shield beam 4 via the balance cylinder 5; a front beam tilt sensor 8, installed on the front beam 3 for detecting the pitch angle α of the front beam 3; a shield beam tilt sensor 9, installed on the shield beam 4 for detecting the tilt angle β of the shield beam 4; and a controller, electrically connected to the front beam tilt sensor 8, the shield beam tilt sensor 9, and each hydraulic actuator, for executing the high-level front-end top coal caving control method.

[0077] In this invention, a complete hardware system architecture for implementing a high-position front-end top coal caving control method is constructed through the integrated configuration of a high-position front-end top coal caving hydraulic support, a front beam inclination sensor 8, a shield beam inclination sensor 9, and a controller. The hydraulic support provides the mechanical execution basis, the dual inclination sensors provide state perception capability, and the controller provides intelligent decision-making function. The components are electrically connected to form a complete loop for information acquisition, processing, and control execution, laying the hardware foundation for the engineering implementation of complex control algorithms.

[0078] Specifically, the high-position front-end coal caving hydraulic support has basic components such as side guard plate 1, telescopic beam 2, front beam 3, balance cylinder 5, column 6, and pushing cylinder 7. The front beam 3 is hinged to the shield beam 4 through the balance cylinder 5 to form an adjustable coal caving window structure. The front beam tilt sensor 8 is installed on the front beam 3 to monitor the pitch angle of the front beam 3 relative to the horizontal plane in real time, providing direct status feedback for coal caving window control. The shield beam tilt sensor 9 is installed on the shield beam 4 to monitor the overall tilt state of the support, providing reference information for support stability control. The controller, as the core processing unit of the system, receives sensor signals, executes control algorithms, and outputs control commands. The electrical connection with each hydraulic actuator ensures that the control commands can be accurately transmitted and executed.

[0079] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling high-level front-end top coal caving, characterized in that, By controlling the high-position front-end top-coal caving hydraulic support to continuously execute the following steps during the normal coal cutting process of the coal mining machine, coordinated operation of coal caving with the machine can be achieved: S1. When the coal mining machine advances to the distance between the hydraulic support and the machine, control the telescopic beam and the side guard plate to retract synchronously to provide distance for the support moving operation. S2. Control the pressure drop of the column to the required pressure for moving the support frame; S3. Control the retraction of the push cylinder to drive the hydraulic support to move forward; S4. Control the column pressure to reach the initial support force requirement, and at the same time perform differential control on the balance cylinder; S5. Control the retraction of the balance cylinder to make the front beam tilt downward to form a coal discharge window. The pitch angle of the front beam is monitored by the front beam tilt angle sensor to control the size of the coal discharge window, so that the top coal can slide down to the front scraper conveyor. S6. Control the extension of the telescopic beam and side plate, stop coal feeding and restore the support status; Step S5 uses sensor feedback to control the size of the coal discharge window, including: monitoring the attitude parameters of the hydraulic support through sensors; calculating control commands based on the attitude parameters; and controlling the action of the balance cylinder to adjust the coal discharge window. A PID control algorithm integrating the front beam tilt angle sensor and the shield beam tilt angle sensor is used to adjust the coal discharge window. Specifically, this includes: calculating the fusion error term based on the front beam pitch angle α detected by the front beam tilt angle sensor and the shield beam tilt angle β detected by the shield beam tilt angle sensor; inputting the fusion error term into the PID control algorithm to generate the control output of the balancing cylinder; and controlling the coordinated action of the balancing cylinder and the column based on the control output. The calculation of the fusion error term includes: Calculate the pitch angle deviation of the front beam: ; Calculate the deviation of the shield beam's tilt angle: ; Calculate the fusion error term: ; in, , The target angles for the front beam and the shield beam are pre-set based on coal discharge experience. , Let be the actual angles at time k. , These are the weighting coefficients.

2. The high-level front-end top coal caving control method according to claim 1, characterized in that, The calculation formula for the PID control algorithm is as follows: ； Where u_k is the control output of the balancing cylinder at time k. For proportional gain, The integral coefficient is... The differential coefficients are... The sampling period.

3. The high-level front-end top coal caving control method according to claim 2, characterized in that, It also includes a cross-coupling compensation step: ； Where u'_k is the compensated control command for the balance cylinder. is the coupling coefficient, used to compensate for the dynamic coupling relationship between the pitch of the front beam and the tilt of the shield beam.

4. The high-level front-end top coal caving control method according to claim 1, characterized in that, Adjust the weighting coefficients according to the top coal flow characteristics: For top coal with soft texture and good fluidity, increase the weighting coefficient. Reduce weighting coefficient Prioritize ensuring that the pitch angle of the front beam is close to the target value; For top coal with hard texture and poor fluidity, increase the weighting coefficient. Reduce weighting coefficient Increase the stability weight of the protective beam.

5. The high-level front-end top coal caving control method according to any one of claims 1-4, characterized in that, Step S6 further includes: The balance cylinder is controlled by numerical feedback from the front beam tilt sensor to keep the front beam in a horizontal state. The height of the support frame is calculated using the tilt sensor of the shield beam, and the column is adjusted to meet the mining requirements.

6. The high-level front-end top coal caving control method according to any one of claims 1-4, characterized in that, It also includes security protection mechanisms: The pitch angle of the front beam detected by the current beam tilt sensor exceeds the safety threshold. At that time, the protection mechanism is forcibly triggered, stopping the coal release operation.

7. The high-level front-end top coal caving control method according to any one of claims 1-4, characterized in that, Multiple hydraulic supports execute steps S1 to S6 sequentially according to the scheduling method to achieve coordinated advancement of coal cutting by the coal mining machine and coal release by the supports.

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