A multi-sensor mine belt conveyor anti-accumulation interlocking control system and method

Abstract

The present application relates to a kind of multi-sensing mine belt conveyor anti-accumulation interlocking control system and method, through the multiple sensors of pre-laying synchronous acquisition belt operation multi-source parameter, weighted fusion quantization risk level by PLC controller, in combination with trend prediction early identification risk, adaptive classification speed regulation is executed to single belt, and upstream and downstream collaborative interlocking control logic is constructed to multiple belts, realize the full closed-loop anti-accumulation control from risk prediction to classification control.This method can greatly reduce the risk of accumulation misjudgment rate, avoid unnecessary downtime under mild risk, balance transportation efficiency and operating energy consumption, effectively improve the operation safety and intelligent control level of mine belt conveying system.

Description

Technical Field

[0001] This invention belongs to the field of coal mine electromechanical automation technology, and particularly relates to a multi-sensor mine belt conveyor anti-accumulation interlocking control system and method. Background Technology

[0002] Belt conveyors are the core equipment for raw coal transfer in underground coal mines. Underground working conditions are complex and the feeding at transfer points fluctuates greatly, making it easy for raw coal to accumulate and blockage. If not handled in time, it can lead to major safety accidents such as slippage, belt breakage, or even mine fire. Therefore, anti-accumulation protection is the core link in the safety management of mining belt conveyors.

[0003] Currently, conventional coal pile protection is a shutdown protection triggered by a single sensor. Only a few improved solutions have introduced multi-sensor data acquisition and simple interlocking, but they still have core shortcomings: Poor interlocking coordination: In multi-level belt conveyor scenarios, the traditional method is a fixed total stop interlock, where a single alarm will cause the entire system to stop, and even minor risks can significantly affect production efficiency.

[0004] The logic is passive and lacks the ability to anticipate events: it only takes action when the coal pile reaches the trigger height, making it impossible to identify the initial accumulation risk in advance. In case of emergencies, the delayed action can easily lead to accidents.

[0005] The system is poorly controlled, resulting in an imbalance between efficiency and energy consumption: It only has two states, "rated operation / emergency stop". Even a slight risk of emergency stop reduces efficiency and damages the equipment. Furthermore, there is no adaptive speed regulation, and constant speed operation under no-load or light-load conditions wastes energy. Summary of the Invention

[0006] (a) Purpose of the invention To overcome the above shortcomings, the present invention aims to provide a multi-sensor mine belt conveyor anti-accumulation interlocking control system and method to solve the above technical problems.

[0007] (II) Technical Solution To achieve the above objectives, the technical solution provided in this application is as follows: A multi-sensor anti-accumulation interlocking control system for a mining belt conveyor includes: an explosion-proof control box, a PLC main controller, a multi-sensor acquisition module, an execution drive module, a communication module, and an explosion-proof power supply module. The PLC main controller, communication module, and explosion-proof power supply module are all installed inside the explosion-proof control box. The multi-sensor acquisition module is connected to the signal input terminal of the PLC main controller, the execution drive module is connected to the signal output terminal of the PLC main controller, and the communication module communicates bidirectionally with the PLC main controller. The PLC main controller is an intrinsically safe mining PLC with built-in coal flow prediction algorithm, multi-machine interlocking logic, and PID speed control program. The execution drive module includes a mining explosion-proof frequency converter, an intermediate relay, a vacuum contactor, and an audible and visual alarm. The frequency converter is connected to the belt motor, and the PLC controls the contactor and alarm via the relay.

[0008] Preferably, the multi-sensor acquisition module includes a belt speed sensor, a material flow infrared sensor, a weighing load sensor, a belt misalignment switch, and a coal pile detection sensor, which collect operating parameters in real time.

[0009] Preferably, the explosion-proof control box is a mining explosion-proof and intrinsically safe control box. The explosion-proof control box has honeycomb-shaped explosion-proof heat dissipation holes and is equipped with a stainless steel dust filter. The explosion-proof control box is equipped with an epoxy-insulated flame-retardant mounting plate inside. The explosion-proof control box has reserved cable entry devices to meet the sealed entry requirements of sensor lines, power lines, and communication lines.

[0010] Preferably, the communication module is a mining intrinsically safe Ethernet switch that supports remote communication between the PLC and the host computer in the underground control room, and also supports network communication between multiple belt conveyor PLCs.

[0011] A method for preventing accumulation and interlocking control of multi-sensor mining belt conveyors, based on a multi-sensor mining belt conveyor anti-accumulation interlocking control system, includes the following specific steps: S1. Multi-source sensor data acquisition: By pre-deploying belt speed sensors, material flow infrared sensors, weighing load sensors, belt misalignment switches and coal pile detection sensors at the corresponding monitoring positions of the belt conveyor, the belt running speed, material flow status, real-time belt load, belt misalignment information and coal pile trigger signal are collected simultaneously and transmitted to the PLC controller. S2, PLC Algorithm Risk Analysis: The PLC controller performs normalization and fusion processing on the received multi-source sensor data, and identifies the current accumulation risk level of the belt conveyor by combining it with the preset accumulation risk judgment threshold. S3. Hierarchical dynamic interlocking control: The PLC controller outputs corresponding interlocking control commands according to the identified risk level: when there is no risk, the rated operating speed of the belt conveyor is maintained; when there is a slight risk, the belt conveyor is controlled to slow down and a material reduction command is sent to the upstream feeding device; when there is a severe risk, the belt conveyor and the upstream feeding device are controlled to stop synchronously and trigger the protection interlock, thereby realizing hierarchical dynamic anti-accumulation control. S4. Remote monitoring closed-loop feedback: The PLC controller uploads real-time sensor data, risk level and control action information to the well remote monitoring platform via industrial Ethernet to complete status feedback and visual monitoring, forming an anti-accumulation control closed loop.

[0012] Preferably, the method for preventing accumulation on a single belt conveyor specifically includes: Multi-source data acquisition: The sensors of the multi-sensor acquisition module collect real-time data parameters such as belt speed, material flow thickness, real-time load, deviation, coal pile height, and other data parameters, and transmit the data to the PLC controller in 500ms cycles. PLC algorithm risk analysis: The PLC controller uses a built-in coal flow prediction algorithm to fuse and analyze multiple collected parameters, and assesses them as light accumulation risk and heavy accumulation risk. The hierarchical dynamic interlocking control works as follows: When the risk level is mild accumulation risk, the PLC controller sends a speed regulation command to the mine explosion-proof frequency converter, which reduces the belt conveyor speed by 10%-30% through the PID speed regulation program. At the same time, the audible and visual alarm issues a yellow warning, but there is no shutdown action. When the risk level is severe accumulation risk, the PLC controller first sends a speed reduction / stop command to the upstream equipment, then reduces the belt conveyor speed to a low speed of 5-10 m / s, and controls the audible and visual alarm to issue a red warning. If the coal accumulation risk is not eliminated within 10 seconds, the PLC controls the vacuum contactor to disconnect, the belt conveyor stops urgently, and the motor starting circuit is locked at the same time. With remote monitoring and closed-loop feedback, after on-site personnel handle the accumulation fault, they send a reset signal to the PLC controller via the intrinsically safe reset button on the explosion-proof control box. The PLC controller then unlocks the motor start circuit, the audible and visual alarm stops, and the belt conveyor resumes normal start, stop, and speed regulation functions.

[0013] Preferably, the quantitative assessment of risk level includes the following: Based on the operating conditions of underground conveyor belts in coal mines, differentiated weights are assigned to five types of parameters: material flow thickness (35%), real-time load (30%), belt speed (20%), coal pile height (10%), and deviation (5%). These weights can be flexibly adjusted via HMI according to different transport volumes and transfer point conditions. The core formula for multi-parameter weighted fusion is: ; The comprehensive score for coal flow accumulation risk ranges from 0 to 100 points; The single-parameter weighting coefficient is the material flow thickness. =0.35, real-time load is W2=0.30, belt speed is W3=0.20, coal pile height is W4=0.10, and belt misalignment is W5=0.05. ; The score is a single-parameter standardized score, ranging from 0 to 100. The actual measured values ​​of each parameter are linearly normalized according to the working condition threshold. The closer the parameter is to the risk critical value, the higher the score. Risk levels are classified according to the following criteria: Normal operating conditions: The weighted comprehensive score S ≤ 60 points, and no parameters meet the triggering conditions for a higher risk level, so control the belt conveyor to maintain the rated speed. Mild accumulation warning risk: The weighted comprehensive score meets 61 points ≤ S ≤ 80 points, or S ≤ 60 points but meets any of the following core conditions: the material flow thickness increases by 30% to 50% for two consecutive collection cycles, the load is 70% to 90% of the rated load, the belt speed decreases by 10% to 20% compared to the rated value, and the coal pile height distance sensor warning threshold is 70% to 85%. In this case, it is judged as a mild accumulation warning risk, the belt conveyor is controlled to reduce speed and a material reduction command is issued to the upstream feeding device. Severe accumulation emergency risk: The weighted comprehensive score meets 81 points ≤ S ≤ 100 points, or S ≤ 80 points but meets any of the core conditions: the coal accumulation sensor triggers a hard protection signal, the load exceeds 90% of the rated value, the belt speed decreases by ≥20% or slips, or the material flow thickness suddenly increases by ≥50%, which is judged as a severe accumulation emergency risk. The belt conveyor and upstream feeding device are controlled to stop synchronously, and the motor starting circuit is locked at the same time. The motor cannot be restarted before the fault is manually cleared and manually reset.

[0014] Preferably, the PLC controller performs trend fitting on parameter changes over five consecutive cycles. If a continuous upward trend in coal flow thickness and load is detected, a mild warning is triggered in advance, even if the hard threshold is not reached, to prevent rapid escalation of risk. Simultaneously, a 3-second risk lock-in mechanism is set to prevent frequent warnings and malfunctions caused by instantaneous parameter fluctuations. The linear trend prediction formula is: ; Where: K is the slope of the risk score change; This is the overall score for the current period; The data collection period is 0.5s; if K>0 and the slope continues to increase, the risk is judged to be on the rise, and an early warning is triggered.

[0015] Preferably, the adaptive speed regulation process of the PLC controller specifically includes the following steps: B1 Baseline Parameter Presets: Preset the rated speed of the belt conveyor; set the no-load baseline speed to 30% of the rated speed; set the graded warning speed reduction ratio: 10%-30% for mild accumulation risk, and 50%-70% for severe accumulation risk; preset PID control parameters: proportional coefficient. =2.5, integral coefficient =0.8, differential coefficient =0.3, the core formula for speed regulation is: ; in: The output value of the PID controller directly corresponds to the output frequency of the frequency converter; =2.5 is the proportional coefficient, which enables rapid response to load deviation; =0.8 is the integral coefficient, which eliminates static error; =0.3 is the differential coefficient, which suppresses parameter fluctuations; To set the deviation value between the set rotational speed and the actual rotational speed; Let | be the integral separation coefficient, when | |≤5% of rated speed =1, activate the points system; | | > 5% =0, disable the integral terminator to prevent integral saturation from causing speed overshoot; B2 load matching speed regulation automatically matches the operating speed according to the real-time load. The specific rules are as follows: When the real-time load is ≤30% of the rated load, it is determined to be an unloaded condition and automatically switches to the unloaded reference speed to reduce unloaded energy consumption. When the real-time load is 30%-70% of the rated load, control the belt conveyor to run smoothly at the rated speed; When the real-time load exceeds 70% of the rated load, the rotation speed is dynamically and finely adjusted according to the load growth rate to avoid material accumulation due to excessive rotation speed. The load / speed matching formula is: ; in, To match the rotational speed in real time; G represents the rated speed of the belt conveyor; G represents the real-time load value. For the rated load value, under no-load conditions, G ≤ 0.3Ge, n = 0.3 To achieve energy saving at low speeds under no-load conditions; B3 Risk-Linked Speed ​​Regulation: Executes corresponding speed regulation actions according to different risk levels: When a mild accumulation warning is triggered, a graded speed reduction is triggered, and the PID output is adjusted synchronously to smoothly reduce the belt speed to the set speed reduction value to avoid material spillage caused by rapid speed reduction; when a severe accumulation risk is detected, the speed is quickly reduced to a safe low speed of 5-10m / s to reserve buffer time for upstream interlock shutdown and prevent belt jamming. B4 Fault-Tolerant Speed ​​Regulation: If the sensor experiences a momentary signal abnormality, the algorithm automatically switches to a preset fixed speed and triggers a fault warning. Once the signal returns to normal, it automatically switches back to adaptive speed regulation mode to ensure continuous system operation.

[0016] Preferably, the dynamic interlocking control method for multiple belt conveyors is based on the anti-accumulation control method for a single belt conveyor, and achieves coordinated control through multi-level interlocking logic. The core process includes: A1 parameter interaction: The PLC controllers of each belt conveyor exchange their own material flow, load and speed parameters in real time through Ethernet switches. The host computer in the underground control room sets the material flow thickness range, load threshold, speed adjustment range and interlock priority of each belt conveyor. A2 start-stop interlock: When starting up, start the belt conveyors in the order of downstream → upstream. After each belt conveyor starts, run stably for 3-7 seconds before starting the next belt conveyor. When stopping, stop the belt conveyors in the order of upstream → downstream to ensure that there is no raw coal residue on the belt conveyors and avoid accumulation. A3 speed control interlock: When a certain level of conveyor belt detects a slight risk of accumulation, its PLC controller transmits the risk signal to the PLC controllers of all upstream conveyor belts. The upstream conveyor belts synchronously reduce speed / stop according to the risk level, while the downstream conveyor belts maintain normal speed or appropriately increase speed to quickly disperse the coal flow. When the accumulation risk is eliminated, the upstream conveyor belts gradually restore to their rated speed in the order from bottom to top. A4 Overload Interlock: When a certain level of belt conveyor detects a severe risk of material accumulation, the PLC controller immediately controls the belt conveyor to reduce its speed and sends an overload signal to all upstream belt conveyors. The upstream belt conveyors stop feeding material until the load drops below 70% of the rated value and normal operation resumes.

[0017] Beneficial effects: 1. Anti-accumulation in advance: By integrating multiple parameters such as material flow, load, and speed, the PLC algorithm can predict the risk of accumulation 5-10 seconds in advance, adjust the speed first, then issue a warning, and finally trigger a shutdown, which greatly reduces the incidence of machine jamming and tearing accidents. 2. Dynamic interlocking reduces energy consumption: Multiple belt conveyors achieve intelligent speed regulation and interlocking based on real-time load. They operate at low speed when unloaded and reduce speed upstream when overloaded, saving 15%-25% of electricity compared to traditional control methods. 3. Explosion-proof, stable and highly reliable: The control box and core components meet the explosion-proof standards for mining, the heat dissipation and dustproof structure is optimized, the equipment failure rate is reduced by 60%, and it is suitable for harsh underground environments; 4. Intelligent centralized control improves efficiency: It supports remote monitoring, parameter setting and fault alarm, and can realize unmanned operation at transfer points, reduce labor costs and improve the level of intelligence in coal mines; 5. Strong compatibility and easy to promote: It can be directly connected to the existing coal mine belt conveyor control system without large-scale modification. The PLC program supports flexible upgrades and is adapted to different models of belt conveyors and transportation scenarios. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of the invention.

[0019] This invention provides a multi-sensor mine belt conveyor anti-accumulation interlocking control method, which is based on a multi-sensor mine belt conveyor anti-accumulation interlocking control system, and includes the following specific steps: S1. Multi-source sensor data acquisition: By pre-deploying belt speed sensors, material flow infrared sensors, weighing load sensors, belt misalignment switches and coal pile detection sensors at the corresponding monitoring positions of the belt conveyor, the belt running speed, material flow status, real-time belt load, belt misalignment information and coal pile trigger signal are collected simultaneously and transmitted to the PLC controller. S2, PLC Algorithm Risk Analysis: The PLC controller performs normalization and fusion processing on the received multi-source sensor data, and identifies the current accumulation risk level of the belt conveyor by combining it with the preset accumulation risk judgment threshold. S3. Hierarchical dynamic interlocking control: The PLC controller outputs corresponding interlocking control commands according to the identified risk level: when there is no risk, the rated operating speed of the belt conveyor is maintained; when there is a slight risk, the belt conveyor is controlled to slow down and a material reduction command is sent to the upstream feeding device; when there is a severe risk, the belt conveyor and the upstream feeding device are controlled to stop synchronously and trigger the protection interlock, thereby realizing hierarchical dynamic anti-accumulation control. S4. Remote monitoring closed-loop feedback: The PLC controller uploads real-time sensor data, risk level and control action information to the well remote monitoring platform via industrial Ethernet to complete status feedback and visual monitoring, forming an anti-accumulation control closed loop.

[0020] Preferably, the method for preventing accumulation on a single belt conveyor specifically includes: Multi-source data acquisition: The sensors of the multi-sensor acquisition module collect real-time data parameters such as belt speed, material flow thickness, real-time load, deviation, coal pile height, and other data parameters, and transmit the data to the PLC controller in 500ms cycles. PLC algorithm risk analysis: The PLC controller uses a built-in coal flow prediction algorithm to fuse and analyze multiple collected parameters, and assesses them as light accumulation risk and heavy accumulation risk. The hierarchical dynamic interlocking control works as follows: When the risk level is mild accumulation risk, the PLC controller sends a speed regulation command to the mine explosion-proof frequency converter, which reduces the belt conveyor speed by 10%-30% through the PID speed regulation program. At the same time, the audible and visual alarm issues a yellow warning, but there is no shutdown action. When the risk level is severe accumulation risk, the PLC controller first sends a speed reduction / stop command to the upstream equipment, then reduces the belt conveyor speed to a low speed of 5-10 m / s, and controls the audible and visual alarm to issue a red warning. If the coal accumulation risk is not eliminated within 10 seconds, the PLC controls the vacuum contactor to disconnect, the belt conveyor stops urgently, and the motor starting circuit is locked at the same time. With remote monitoring and closed-loop feedback, after on-site personnel handle the accumulation fault, they send a reset signal to the PLC controller via the intrinsically safe reset button on the explosion-proof control box. The PLC controller then unlocks the motor start circuit, the audible and visual alarm stops, and the belt conveyor resumes normal start, stop, and speed regulation functions.

[0021] Preferably, the quantitative assessment of risk level includes the following: Based on the operating conditions of underground conveyor belts in coal mines, differentiated weights are assigned to five types of parameters: material flow thickness (35%), real-time load (30%), belt speed (20%), coal pile height (10%), and deviation (5%). These weights can be flexibly adjusted via HMI according to different transport volumes and transfer point conditions. The core formula for multi-parameter weighted fusion is: ; The comprehensive score for coal flow accumulation risk ranges from 0 to 100 points; The single-parameter weighting coefficient is the material flow thickness. =0.35, real-time load is W2=0.30, belt speed is W3=0.20, coal pile height is W4=0.10, and belt misalignment is W5=0.05. ; The score is a single-parameter standardized score, ranging from 0 to 100. The actual measured values ​​of each parameter are linearly normalized according to the working condition threshold. The closer the parameter is to the risk critical value, the higher the score. Risk levels are classified according to the following criteria: Normal operating conditions: The weighted comprehensive score S ≤ 60 points, and no parameters meet the triggering conditions for a higher risk level, so control the belt conveyor to maintain the rated speed. Mild accumulation warning risk: The weighted comprehensive score meets 61 points ≤ S ≤ 80 points, or S ≤ 60 points but meets any of the following core conditions: the material flow thickness increases by 30% to 50% for two consecutive collection cycles, the load is 70% to 90% of the rated load, the belt speed decreases by 10% to 20% compared to the rated value, and the coal pile height distance sensor warning threshold is 70% to 85%. In this case, it is judged as a mild accumulation warning risk, the belt conveyor is controlled to reduce speed and a material reduction command is issued to the upstream feeding device. Severe accumulation emergency risk: The weighted comprehensive score meets 81 points ≤ S ≤ 100 points, or S ≤ 80 points but meets any of the core conditions: the coal accumulation sensor triggers a hard protection signal, the load exceeds 90% of the rated value, the belt speed decreases by ≥20% or slips, or the material flow thickness suddenly increases by ≥50%, which is judged as a severe accumulation emergency risk. The belt conveyor and upstream feeding device are controlled to stop synchronously, and the motor starting circuit is locked at the same time. The motor cannot be restarted before the fault is manually cleared and manually reset.

[0022] Preferably, the PLC controller performs trend fitting on parameter changes over five consecutive cycles. If a continuous upward trend in coal flow thickness and load is detected, a mild warning is triggered in advance, even if the hard threshold is not reached, to prevent rapid escalation of risk. Simultaneously, a 3-second risk lock-in mechanism is set to prevent frequent warnings and malfunctions caused by instantaneous parameter fluctuations. The linear trend prediction formula is: ; Where: K is the slope of the risk score change; This is the overall score for the current period; The data collection period is 0.5s; if K>0 and the slope continues to increase, the risk is judged to be on the rise, and an early warning is triggered.

[0023] Preferably, the adaptive speed regulation process of the PLC controller specifically includes the following steps: B1 Baseline Parameter Presets: Preset the rated speed of the belt conveyor; set the no-load baseline speed to 30% of the rated speed; set the graded warning speed reduction ratio: 10%-30% for mild accumulation risk, and 50%-70% for severe accumulation risk; preset PID control parameters: proportional coefficient. =2.5, integral coefficient =0.8, differential coefficient =0.3, the core formula for speed regulation is: ; in: The output value of the PID controller directly corresponds to the output frequency of the frequency converter; =2.5 is the proportional coefficient, which enables rapid response to load deviation; =0.8 is the integral coefficient, which eliminates static error; =0.3 is the differential coefficient, which suppresses parameter fluctuations; To set the deviation value between the set rotational speed and the actual rotational speed; Let | be the integral separation coefficient, when | |≤5% of rated speed =1, activate the points system; | | > 5% =0, disable the integral terminator to prevent integral saturation from causing speed overshoot; B2 load matching speed regulation automatically matches the operating speed according to the real-time load. The specific rules are as follows: When the real-time load is ≤30% of the rated load, it is determined to be an unloaded condition and automatically switches to the unloaded reference speed to reduce unloaded energy consumption. When the real-time load is 30%-70% of the rated load, control the belt conveyor to run smoothly at the rated speed; When the real-time load exceeds 70% of the rated load, the rotation speed is dynamically and finely adjusted according to the load growth rate to avoid material accumulation due to excessive rotation speed. The load / speed matching formula is: ; in, To match the rotational speed in real time; G represents the rated speed of the belt conveyor; G represents the real-time load value. For the rated load value, under no-load conditions, G ≤ 0.3Ge, n = 0.3 To achieve energy saving at low speeds under no-load conditions; B3 Risk-Linked Speed ​​Regulation: Executes corresponding speed regulation actions according to different risk levels: When a mild accumulation warning is triggered, a graded speed reduction is triggered, and the PID output is adjusted synchronously to smoothly reduce the belt speed to the set speed reduction value to avoid material spillage caused by rapid speed reduction; when a severe accumulation risk is detected, the speed is quickly reduced to a safe low speed of 5-10m / s to reserve buffer time for upstream interlock shutdown and prevent belt jamming. B4 Fault-Tolerant Speed ​​Regulation: If the sensor experiences a momentary signal abnormality, the algorithm automatically switches to a preset fixed speed and triggers a fault warning. Once the signal returns to normal, it automatically switches back to adaptive speed regulation mode to ensure continuous system operation.

[0024] Preferably, the dynamic interlocking control method for multiple belt conveyors is based on the anti-accumulation control method for a single belt conveyor, and achieves coordinated control through multi-level interlocking logic. The core process includes: A1 parameter interaction: The PLC controllers of each belt conveyor exchange their own material flow, load and speed parameters in real time through Ethernet switches. The host computer in the underground control room sets the material flow thickness range, load threshold, speed adjustment range and interlock priority of each belt conveyor. A2 start-stop interlock: When starting up, start the belt conveyors in the order of downstream → upstream. After each belt conveyor starts, run stably for 3-7 seconds before starting the next belt conveyor. When stopping, stop the belt conveyors in the order of upstream → downstream to ensure that there is no raw coal residue on the belt conveyors and avoid accumulation. A3 speed control interlock: When a certain level of conveyor belt detects a slight risk of accumulation, its PLC controller transmits the risk signal to the PLC controllers of all upstream conveyor belts. The upstream conveyor belts synchronously reduce speed / stop according to the risk level, while the downstream conveyor belts maintain normal speed or appropriately increase speed to quickly disperse the coal flow. When the accumulation risk is eliminated, the upstream conveyor belts gradually restore to their rated speed in the order from bottom to top. A4 Overload Interlock: When a certain level of belt conveyor detects a severe risk of material accumulation, the PLC controller immediately controls the belt conveyor to reduce its speed and sends an overload signal to all upstream belt conveyors. The upstream belt conveyors stop feeding material until the load drops below 70% of the rated value and normal operation resumes.

[0025] The multi-sensor mine belt conveyor anti-accumulation interlocking control method of this invention achieves early identification and quantification of accumulation risks through multi-source sensor data fusion, combined with weighted scoring and trend prediction. Based on the risk level, it performs adaptive graded speed adjustment on a single belt, and achieves dynamic control with multi-machine graded collaborative interlocking. It can effectively solve the core pain points of traditional coal pile protection logic, such as passive lag, high false alarm rate, coarse control, and poor interlocking coordination. Compared with traditional solutions, this method can predict risks in advance, significantly reduce the probability of false alarms, balance production efficiency and operating energy consumption, reduce unnecessary shutdowns under mild risks, and effectively improve the operational safety and intelligent control level of mine belt conveyor systems.

[0026] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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. Such 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 multi-sensor anti-accumulation interlocking control system for mining belt conveyors, characterized in that, include: The system comprises an explosion-proof control box, a PLC main controller, a multi-sensor acquisition module, an execution drive module, a communication module, and an explosion-proof power supply module. The PLC main controller, communication module, and explosion-proof power supply module are all installed inside the explosion-proof control box. The multi-sensor acquisition module is connected to the signal input terminal of the PLC main controller, the execution drive module is connected to the signal output terminal of the PLC main controller, and the communication module communicates bidirectionally with the PLC main controller. The PLC main controller is an intrinsically safe PLC for mining applications, with built-in coal flow prediction algorithms, multi-machine interlocking logic, and PID speed control programs. The execution drive module includes a mining explosion-proof frequency converter, intermediate relays, vacuum contactors, and an audible and visual alarm. The frequency converter is connected to a belt motor, and the PLC controls the contactors and alarm via relays.

2. The multi-sensor mine belt conveyor anti-accumulation interlocking control system according to claim 1, characterized in that, The multi-sensor acquisition module includes a belt speed sensor, a material flow infrared sensor, a weighing load sensor, a belt misalignment switch, and a coal pile detection sensor, which collect operating parameters in real time.

3. The multi-sensor mine belt conveyor anti-accumulation interlocking control system according to claim 1, characterized in that, The explosion-proof control box is a mining-grade explosion-proof and intrinsically safe control box. The explosion-proof control box has honeycomb-shaped explosion-proof heat dissipation holes and is equipped with a stainless steel dust filter. The explosion-proof control box is equipped with an epoxy-insulated flame-retardant mounting plate. The explosion-proof control box has a reserved cable entry device to meet the sealed entry requirements of sensor lines, power lines, and communication lines.

4. The multi-sensor mine belt conveyor anti-accumulation interlocking control system according to claim 1, characterized in that, The communication module is an intrinsically safe Ethernet switch for mining, which supports remote communication between the PLC and the host computer in the underground control room, and also supports network communication between multiple belt conveyor PLCs.

5. A method for interlocking control of multi-sensor mining belt conveyors to prevent accumulation, characterized in that, The multi-sensor mine belt conveyor anti-accumulation interlocking control system based on any one of claims 1-4 includes the following specific steps: S1. Multi-source sensor data acquisition: By pre-deploying belt speed sensors, material flow infrared sensors, weighing load sensors, belt misalignment switches and coal pile detection sensors at the corresponding monitoring positions of the belt conveyor, the belt running speed, material flow status, real-time belt load, belt misalignment information and coal pile trigger signal are collected simultaneously and transmitted to the PLC controller. S2, PLC Algorithm Risk Analysis: The PLC controller performs normalization and fusion processing on the received multi-source sensor data, and identifies the current accumulation risk level of the belt conveyor by combining it with the preset accumulation risk judgment threshold. S3. Hierarchical dynamic interlocking control: The PLC controller outputs corresponding interlocking control commands according to the identified risk level: when there is no risk, the rated operating speed of the belt conveyor is maintained; when there is a slight risk, the belt conveyor is controlled to slow down and a material reduction command is sent to the upstream feeding device; when there is a severe risk, the belt conveyor and the upstream feeding device are controlled to stop synchronously and trigger the protection interlock, thereby realizing hierarchical dynamic anti-accumulation control. S4. Remote monitoring closed-loop feedback: The PLC controller uploads real-time sensor data, risk level and control action information to the well remote monitoring platform via industrial Ethernet to complete status feedback and visual monitoring, forming an anti-accumulation control closed loop.

6. The method for anti-accumulation interlocking control of a multi-sensor mining belt conveyor according to claim 5, characterized in that, The specific methods for preventing accumulation on a single belt conveyor include: Multi-source data acquisition: The sensors of the multi-sensor acquisition module collect real-time data parameters such as belt speed, material flow thickness, real-time load, deviation, coal pile height, and other data parameters, and transmit the data to the PLC controller in 500ms cycles. PLC algorithm risk analysis: The PLC controller uses a built-in coal flow prediction algorithm to fuse and analyze multiple collected parameters, and assesses them as light accumulation risk and heavy accumulation risk. The hierarchical dynamic interlocking control works as follows: When the risk level is mild accumulation risk, the PLC controller sends a speed regulation command to the mine explosion-proof frequency converter, which reduces the belt conveyor speed by 10%-30% through the PID speed regulation program. At the same time, the audible and visual alarm issues a yellow warning, but there is no shutdown action. When the risk level is severe accumulation risk, the PLC controller first sends a speed reduction / stop command to the upstream equipment, then reduces the belt conveyor speed to a low speed of 5-10 m / s, and controls the audible and visual alarm to issue a red warning. If the coal accumulation risk is not eliminated within 10 seconds, the PLC controls the vacuum contactor to disconnect, the belt conveyor stops urgently, and the motor starting circuit is locked at the same time. With remote monitoring and closed-loop feedback, after on-site personnel handle the accumulation fault, they send a reset signal to the PLC controller via the intrinsically safe reset button on the explosion-proof control box. The PLC controller then unlocks the motor start circuit, the audible and visual alarm stops, and the belt conveyor resumes normal start, stop, and speed regulation functions.

7. The method for interlocking control of multi-sensor mining belt conveyors against accumulation according to claim 6, characterized in that, The quantitative assessment of risk levels specifically includes the following: Based on the operating conditions of underground conveyor belts in coal mines, differentiated weights are assigned to five types of parameters: material flow thickness (35%), real-time load (30%), belt speed (20%), coal pile height (10%), and deviation (5%). These weights can be flexibly adjusted via HMI according to different transport volumes and transfer point conditions. The core formula for multi-parameter weighted fusion is: ； The comprehensive score for coal flow accumulation risk ranges from 0 to 100 points; The single-parameter weighting coefficient is the material flow thickness. =0.35, real-time load is W2=0.30, belt speed is W3=0.20, coal pile height is W4=0.10, and belt misalignment is W5=0.

05. ; The score is a single-parameter standardized score, ranging from 0 to 100. The actual measured values ​​of each parameter are linearly normalized according to the working condition threshold. The closer the parameter is to the risk critical value, the higher the score. Risk levels are classified according to the following criteria: Normal operating conditions: The weighted comprehensive score S ≤ 60 points, and no parameters meet the triggering conditions for a higher risk level, so control the belt conveyor to maintain the rated speed. Mild accumulation warning risk: The weighted comprehensive score meets 61 points ≤ S ≤ 80 points, or S ≤ 60 points but meets any of the following core conditions: the material flow thickness increases by 30% to 50% for two consecutive collection cycles, the load is 70% to 90% of the rated load, the belt speed decreases by 10% to 20% compared to the rated value, and the coal pile height distance sensor warning threshold is 70% to 85%. In this case, it is judged as a mild accumulation warning risk, the belt conveyor is controlled to reduce speed and a material reduction command is issued to the upstream feeding device. Severe accumulation emergency risk: The weighted comprehensive score meets 81 points ≤ S ≤ 100 points, or S ≤ 80 points but meets any of the core conditions: the coal accumulation sensor triggers a hard protection signal, the load exceeds 90% of the rated value, the belt speed decreases by ≥20% or slips, or the material flow thickness suddenly increases by ≥50%, which is judged as a severe accumulation emergency risk. The belt conveyor and upstream feeding device are controlled to stop synchronously, and the motor starting circuit is locked at the same time. The motor cannot be restarted before the fault is manually cleared and manually reset.

8. The method for interlocking control of multi-sensor mining belt conveyors against accumulation according to claim 7, characterized in that, The PLC controller performs trend fitting on parameter changes over five consecutive cycles. If a continuous upward trend in coal flow thickness and load is detected, a mild warning is triggered in advance, even if the hard threshold is not reached, to prevent rapid escalation of risk. Simultaneously, a 3-second risk lock-in mechanism is set to prevent frequent warnings and malfunctions caused by instantaneous parameter fluctuations. The linear trend prediction formula is: ； Where: K is the slope of the risk score change; This is the overall score for the current period; The data collection period is 0.5s; if K>0 and the slope continues to increase, the risk is judged to be on the rise, and an early warning is triggered.

9. A multi-sensor mining belt conveyor anti-accumulation interlocking control method according to claim 8, characterized in that, The adaptive speed regulation process of the PLC controller specifically includes the following steps: B1 Baseline Parameter Presets: Preset the rated speed of the belt conveyor; set the no-load baseline speed to 30% of the rated speed; set the graded warning speed reduction ratio: 10%-30% for mild accumulation risk, and 50%-70% for severe accumulation risk; preset PID control parameters: proportional coefficient. =2.5, integral coefficient =0.8, differential coefficient =0.3, the core formula for speed regulation is: ； in: The output value of the PID controller directly corresponds to the output frequency of the frequency converter. =2.5 is the proportional coefficient, which enables rapid response to load deviation; =0.8 is the integral coefficient, which eliminates static error; =0.3 is the differential coefficient, which suppresses parameter fluctuations; To set the deviation value between the set rotational speed and the actual rotational speed; Let | be the integral separation coefficient, when | |≤5% of rated speed =1, activate the points system; | | > 5% =0, disable the integral terminator to prevent integral saturation from causing speed overshoot; B2 load matching speed regulation automatically matches the operating speed according to the real-time load. The specific rules are as follows: When the real-time load is ≤30% of the rated load, it is determined to be an unloaded condition and automatically switches to the unloaded reference speed to reduce unloaded energy consumption. When the real-time load is 30%-70% of the rated load, control the belt conveyor to run smoothly at the rated speed; When the real-time load exceeds 70% of the rated load, the rotation speed is dynamically and finely adjusted according to the load growth rate to avoid material accumulation due to excessive rotation speed. The load / speed matching formula is: ; in, To match the rotational speed in real time; G represents the rated speed of the belt conveyor; G represents the real-time load value. For the rated load value, under no-load conditions, G ≤ 0.3Ge, n = 0.3 To achieve energy saving at low speeds under no-load conditions; B3 Risk-Linked Speed ​​Regulation: Executes corresponding speed regulation actions according to different risk levels: When a mild accumulation warning is triggered, a graded speed reduction is triggered, and the PID output is adjusted synchronously to smoothly reduce the belt speed to the set speed reduction value to avoid material spillage caused by rapid speed reduction; when a severe accumulation risk is detected, the speed is quickly reduced to a safe low speed of 5-10m / s to reserve buffer time for upstream interlock shutdown and prevent belt jamming. B4 Fault-Tolerant Speed ​​Regulation: If the sensor experiences a momentary signal abnormality, the algorithm automatically switches to a preset fixed speed and triggers a fault warning. Once the signal returns to normal, it automatically switches back to adaptive speed regulation mode to ensure continuous system operation.

10. A multi-sensor mining belt conveyor anti-accumulation interlocking control method according to any one of claims 6-9, characterized in that, The dynamic interlocking control method for multiple belt conveyors is based on the anti-accumulation control method for a single belt conveyor, and achieves coordinated control through multi-level interlocking logic. The core process includes: A1 parameter interaction: The PLC controllers of each belt conveyor exchange their own material flow, load and speed parameters in real time through Ethernet switches. The host computer in the underground control room sets the material flow thickness range, load threshold, speed adjustment range and interlock priority of each belt conveyor. A2 start-stop interlock: When starting up, start the belt conveyors in the order of downstream → upstream. After each belt conveyor starts, run stably for 3-7 seconds before starting the next belt conveyor. When stopping, stop the belt conveyors in the order of upstream → downstream to ensure that there is no raw coal residue on the belt conveyors and avoid accumulation. A3 speed control interlock: When a certain level of conveyor belt detects a slight risk of accumulation, its PLC controller transmits the risk signal to the PLC controllers of all upstream conveyor belts. The upstream conveyor belts synchronously reduce speed / stop according to the risk level, while the downstream conveyor belts maintain normal speed or appropriately increase speed to quickly disperse the coal flow. When the accumulation risk is eliminated, the upstream conveyor belts gradually restore to their rated speed in the order from bottom to top. A4 Overload Interlock: When a certain level of belt conveyor detects a severe risk of material accumulation, the PLC controller immediately controls the belt conveyor to reduce its speed and sends an overload signal to all upstream belt conveyors. The upstream belt conveyors stop feeding material until the load drops below 70% of the rated value and normal operation resumes.

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