A main coal flow transportation balance control method and device and a storage medium

Abstract

The present application relates to the technical field of coal mine main coal flow transportation system control, and more particularly to a main coal flow transportation balance control method, device and computer storage medium. The main coal flow transportation balance control method uses a structured light stereo vision method, projects structured light onto the surface of an object, the projected light stripe changes with the ups and downs of the surface shape of the object, and the surface image of the conveyor belt is shot. The cross-sectional area of the object is extracted from the stripe pattern modulated by the surface shape of the conveyor belt, and then the volume of coal on the conveyor belt is calculated to realize real-time detection of coal flow, effectively grasp the real-time coal flow of the entire main transportation system, achieve the purpose of balanced transportation of coal, improve the utilization rate of equipment, and reduce the power consumption and loss of equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mine main coal flow transportation system control, in particular to a main coal flow transportation balance control method and device and computer storage medium. BACKGROUND

[0002] Coal flow balance technology is a technology developed to address the problem of uneven distribution of coal flow in underground coal mines. In the production process of coal mines, the coal flow at multiple locations such as the import and export of each working face and the scraper conveyor may be different, which can cause coal accumulation and retention, affect production efficiency, and increase safety hazards such as fire and gas. Coal flow balance technology realizes balanced transportation of coal flow through real-time detection, measurement and scheduling of coal flow, so that the coal flow of each process is basically the same, and the flow speed and direction of coal in the roadway are stable. The core of this technology is the joint application of underground sensors, PLC control systems and upper computer monitoring systems, which collects, analyzes and processes coal flow data, and realizes precise control of coal flow through frequency conversion technology.

[0003] The application of coal flow balance technology can improve the production efficiency of coal mines, reduce equipment failure and maintenance downtime, reduce energy consumption and cost, and also enhance the safety management capability of underground mines, making a positive contribution to resource conservation and environmental protection.

[0004] The main coal flow transportation system involves coal mining machines, scraper conveyors, transfer machines, belt conveyors and other equipment. Due to the uncontrollable coal quantity of each production link and the time-varying nature of coal quantity, it can cause short-term imbalance of coal flow transportation, such as coal stacking failure caused by excessive coal quantity in a short time, belt conveyor overload, leading to shutdown of the entire main coal flow transportation system, or equipment idle and light load operation for too long due to insufficient coal quantity, resulting in energy waste and low equipment utilization. The purpose is to solve the imbalance of coal flow transportation, prevent coal stacking and overload failure, and reduce the idle and light load time of equipment.

[0005] The existing technology lacks technical means combining real-time coal quantity detection with coal flow tracking, and cannot provide accurate data basis for the control system; manual adjustment has problems such as high labor cost, low efficiency, poor timeliness, and low control accuracy. Some coal mines use frequency conversion driving, but most of them do not realize speed regulation according to coal quantity, resulting in low equipment utilization. SUMMARY

[0006] Therefore, the technical problem to be solved by the present application is to overcome the problem that the existing technology lacks technical means combining real-time coal quantity detection with coal flow tracking, and cannot provide accurate data basis for the control system.

[0007] To solve the above technical problems, the present application provides a main coal flow transportation balance control method, which comprises:

[0008] acquire a surface image at a preset coal flow detection position on the belt conveyor after the structured light irradiation;

[0009] extract a cross-sectional area of the coal according to the surface image, and calculate a coal flow in a preset time length in real time;

[0010] divide the belt conveyor into a plurality of regions, assign each region according to the real-time collected coal flow, and track the coal flow according to a running speed of the belt conveyor;

[0011] calculate a speed regulation value according to the tracking information of the coal flow, and send a speed regulation instruction to the belt conveyor.

[0012] Preferably, the extracting the cross-sectional area of the coal according to the surface image, and calculating the coal flow in the preset time length in real time comprises:

[0013] calculating the coal flow in the preset time length in real time according to an image acquisition time interval, the cross-sectional area of the coal, a real-time belt speed, and a density of the coal.

[0014] Preferably, the preset coal flow detection position is arranged at a preset distance from a tail position of a next-stage belt conveyor, and the preset distance is calculated according to a current belt conveyor rated speed, an acceleration time set by a frequency converter of the next-stage belt conveyor, a motor rated frequency of the next-stage belt conveyor, a braking safety distance, and a coal amount detection distance.

[0015] Preferably, the sending the speed regulation instruction to the belt conveyor comprises:

[0016] when the speed regulation value is different from an actual belt speed, and the speed regulation value is the same in a plurality of continuous calculations, sending the speed regulation instruction to the belt conveyor.

[0017] Preferably, if the speed regulation instruction is to speed up, the speed of the next-stage belt conveyor is increased by a first response time before a coal flow increasing node reaches the next-stage belt conveyor.

[0018] if the speed regulation instruction is to slow down, the belt speed is not adjusted when a coal flow decreasing node reaches the current-stage belt conveyor, and the current-stage belt conveyor is slowed down after a second response time.

[0019] Preferably, the calculating the speed regulation value according to the tracking information of the coal flow, and sending the speed regulation instruction to the belt conveyor comprises:

[0020] when it is detected or predicted that the coal flow is not greater than a first threshold value, and no coal amount point with the coal flow greater than the first threshold value is found on the current belt conveyor after a third response time, issuing a low-speed mode instruction.

[0021] When the coal flow is detected or predicted to be greater than the first threshold value and not greater than the second threshold value, a medium-speed mode instruction is issued;

[0022] When the coal flow is detected or predicted to be greater than the second threshold value, a high-speed mode instruction is issued.

[0023] When the coal flow is detected or predicted to be greater than the second threshold value, and after a delay of the fourth response duration, there is no coal flow on the current belt conveyor exceeding the coal amount point of the second threshold value, a medium-speed mode instruction is issued.

[0024] Preferably, the main coal flow transportation balancing control method further comprises:

[0025] When the coal flow tracking reaches the next coal flow detection point, and there is no coal at the next coal flow detection point, a coal blocking alarm is issued, and the system is stopped.

[0026] Preferably, the main coal flow transportation balancing control method further comprises:

[0027] When the coal flow on the belt conveyor is detected or predicted to exceed the rated value, a coal stacking alarm is issued, and the coal mining machine is reduced.

[0028] The application also provides a main coal flow transportation balancing control device, comprising:

[0029] An image acquisition module is configured to acquire a surface image of a preset coal flow detection position on the belt conveyor after the structured light irradiation.

[0030] A coal flow detection module is configured to extract a cross-sectional area of the coal according to the surface image, and calculate the coal flow within a preset time duration in real time.

[0031] A coal flow tracking module is configured to divide the belt conveyor into a plurality of regions, assign each region by using the real-time acquired coal flow, and track the coal flow according to the running speed of the belt conveyor.

[0032] A speed regulation module is configured to calculate a speed regulation value according to the tracking information of the coal flow, and send a speed regulation instruction to the belt conveyor.

[0033] The application also provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the above-mentioned main coal flow transportation balancing control method.

[0034] The above technical solutions of the application have the following advantages compared with the prior art:

[0035] The main coal flow transportation balance control method provided by the application uses a structured light stereo vision method, structured light is projected onto the surface of an object, the projected light strip changes following the ups and downs of the surface shape of the object, the surface image of the conveyor belt is shot, the cross-sectional area of the object is extracted from the stripe pattern modulated by the surface shape of the conveyor belt, and then the coal volume on the current conveyor belt is obtained through calculation, so that the real-time detection of the coal flow is realized, the real-time coal flow of the whole main transportation system is effectively mastered, the purpose of balanced transportation of the coal volume is achieved, the equipment utilization rate is improved, and the power consumption and loss of the equipment are reduced. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to make the content of the application more easily understood, the application will be further described in detail below according to specific embodiments of the application and in conjunction with the drawings, in which:

[0037] Figure 1 is a flow chart of the main transportation system;

[0038] Figure 2 is a topological diagram of the control system;

[0039] Figure 3 is a flow chart of the main coal flow transportation balance control method provided by the application;

[0040] Figure 4 is a system diagram of the coal flow monitoring device;

[0041] Figure 5 is a schematic diagram of the installation position of the coal flow monitoring device;

[0042] Figure 6 is a speed regulation flow chart;

[0043] Figure 7 is a schematic diagram of the main coal flow transportation system. DETAILED DESCRIPTION

[0044] The core of the application is to provide a main coal flow transportation balance control method, device and computer storage medium, effectively master the real-time coal flow of the whole main transportation system, and achieve the purpose of balanced transportation of the coal volume.

[0045] In order to make the personnel in the technical field better understand the application scheme, the application will be further described in detail below in conjunction with the drawings and specific embodiments. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the application.

[0046] The coal mine underground includes two fully mechanized working faces, a scraper conveyor transports the coal of the coal mining machine to a transloading machine, the transloading machine transports the coal to a crossheading belt conveyor, and then the coal is transported to the ground through a main haulage roadway belt conveyor and a main inclined shaft belt conveyor, and the whole transportation process is as shown in Figure 1 .

[0047] The coal flow balance control system topological graph is as shown in Figure 2 The topological structure adopts a combination of master control and hierarchical control, the main inclined shaft PLC is a master control PLC, responsible for the start-stop, speed regulation and protection control of each belt conveyor and fully mechanized working face, and each belt conveyor PLC is responsible for the control and protection of the equipment at this level and uploads information to the master control PLC and the upper computer.

[0048] (1) Upper computer monitoring system

[0049] The server and configuration software are used to realize centralized control and working condition display of the main transportation system.

[0050] (2) PLC control system

[0051] Responsible for information interaction with the host of the protection device, the frequency converter and the sensor, and realizes the control and information uploading of the field equipment.

[0052] In order to ensure the stability of the data communication system, the PLCs communicate with each other through the underground ring network by using optical fibers, and the upper computer collects data and issues instructions through the underground ring network.

[0053] (3) Field detection and execution equipment

[0054] The frequency converter is used to drive the belt conveyor and realize speed regulation of the belt conveyor, and the comprehensive protection device includes deviation protection, coal piling protection, speed protection, smoke protection, temperature protection, longitudinal tearing protection and emergency stop locking protection, etc., and is used for the protection function of the belt conveyor in abnormal conditions.

[0055] Please refer to Figure 3 , Figure 3 The implementation flowchart of the main coal flow transportation balance control method provided by the present application is as follows:

[0056] S101: Obtain the surface image at the preset coal flow detection position of the belt conveyor after the structured light irradiation;

[0057] S102: Extract the cross-sectional area of the coal according to the surface image, and calculate the coal flow in a preset time period in real time;

[0058] S103: Divide the belt conveyor into several regions, assign a value to each region using the real-time collected coal flow, and track the coal flow according to the running speed of the belt conveyor;

[0059] S104: Calculate the speed regulation value according to the tracking information of the coal flow, and send a speed regulation instruction to the belt conveyor.

[0060] Based on the above embodiment, steps S101 and S102 are described in detail:

[0061] A coal flow monitoring device is set to detect real-time coal quantity information on the belt conveyor:

[0062] The coal flow monitoring device uses stereo vision technology, uses a combination of binocular cameras and laser light sources, uses a structured light stereo vision method, projects a standard grating stripe structured light onto the object surface, the projected light stripe changes with the ups and downs of the object surface shape, the camera captures the surface image of the conveyor belt, extracts the three-dimensional volume of the object from the stripe pattern modulated by the conveyor belt surface shape, and then calculates the current coal volume on the conveyor belt after software processing and operation, realizes real-time detection of coal flow, and the device system diagram is shown in Figure 4 .

[0063] During the operation of the belt conveyor, the coal flow continuously passes through the detection position, and the cross section of the coal passing through the detection position is integrated to calculate the volume of the coal, and the mass of the coal can be obtained through the coal density. In a preset time interval [0, t n ], the mass of the coal passing through the detection position is:

[0064]

[0065] In the formula, p is the density of the coal;

[0066] t s is the time interval of image acquisition;

[0067] S i is the cross-sectional area calculated by the i-th image acquisition;

[0068] v i is the real-time belt speed at the i-th acquisition time.

[0069] In order to ensure that the downstream belt conveyor has sufficient speed regulation time, it is necessary to determine the installation position of the coal flow monitoring device.

[0070] As Figure 5 shown, the belt conveyor A is driven by a frequency converter, and the coal flow monitoring device is installed at a position L away from the tail of the belt conveyor A. The calculation formula of the distance L is:

[0071] L=Vb *[T a F h / (F h -F1)]+L s +L T

[0072] L - sensor distance from the head;

[0073] V b - rated speed of the belt conveyor B;

[0074] T a - acceleration time set by the frequency converter of the belt conveyor A;

[0075] F h - rated frequency of the motor of the belt conveyor A;

[0076] L s - braking safety distance;

[0077] L v - coal quantity detection distance.

[0078] Based on the above embodiment, the step S103 is described in detail:

[0079] In order to grasp the coal quantity on the belt conveyor in real time, a coal quantity tracking model is established, the conveying belt is divided into a plurality of regions, the real-time collected coal quantity information is assigned to each region, and then stack processing is performed, and the coal quantity running track on the belt conveyor can be obtained according to the running speed of the belt conveyor. The tracking and superposition method is used for numerical storage of the superimposed part of the coal quantity of two disc regions, and the superimposed coal quantity is superimposed and tracked on the conveying belt, serving as the data basis for speed regulation.

[0080] (1) Speed regulation principle: overall transportation, pre-acceleration, and lagging deceleration.

[0081] 1) Overall transportation: through data tracking of the coal flow on the belt conveyor, single value tracking and superposition tracking are divided, the coal flow at each point on the belt conveyor is grasped in real time, and speed regulation and early warning are performed.

[0082] 2) Pre-acceleration: when the acceleration instruction is issued, and the coal flow increasing node has not reached the next level belt conveyor, the speed of the next level belt conveyor is increased by the first response time in advance.

[0083] 3) Lagging deceleration: when the deceleration instruction is issued, and the coal flow decreasing node reaches the current level belt conveyor, the belt speed is not adjusted temporarily. After a delay of the second response time, the current level belt conveyor is decelerated.

[0084] The safety distance for adjusting the speed of the belt conveyor is set, and the response time is the time required for the coal flow node to pass through the safety distance. Each level of variable speed belt conveyor has a corresponding safety distance and response time, which are set according to the specific conditions of each level of variable speed belt conveyor.

[0085] (2) Speed ​​adjustment process:

[0086] The calculated speed regulation value from the model is compared with the actual belt speed of the belt conveyor. If the two values ​​differ, the calculated speed regulation value for the next three consecutive times needs to be obtained. If the three calculated speed regulation values ​​are the same, the system issues a speed regulation command. Otherwise, the belt conveyor operates at its original belt speed.

[0087] Speed ​​regulation flowchart as follows Figure 6 As shown:

[0088] (3) Speed ​​setting:

[0089] To ensure the stability of the speed control system and reduce the impact on the equipment, it is set to a 3-speed mode.

[0090] 1) Low speed mode: When the coal quantity is detected or predicted to be no greater than the first threshold (40% of the rated coal quantity), the third response time is delayed, and then it is determined whether there is a coal flow rate on this belt conveyor that exceeds 40% of the rated coal quantity. If not, a low speed mode command is issued; if it exceeds 40% of the rated coal quantity, it will still run at the original speed.

[0091] 2) Medium speed mode:

[0092] a) Switch from low speed to medium speed; when the detected or predicted coal quantity is greater than 40% but not greater than the second threshold (70% of the rated coal quantity).

[0093] When that happens, a medium-speed mode command is issued.

[0094] b) Switch from high speed to medium speed; when the coal quantity is detected or predicted to be greater than 70% of the rated coal quantity, delay the fourth response time, and then determine whether there is a coal flow rate on this belt conveyor that exceeds 70% of the rated coal quantity. If not, issue a medium speed mode command; if there is a coal flow rate that exceeds 70% of the rated coal quantity, continue to operate in high speed mode.

[0095] 3) High-speed mode:

[0096] When the detected or predicted coal quantity exceeds 70% of the rated coal quantity, a high-speed mode command is issued.

[0097] (4) Protection functions:

[0098] a) coal blocking alarm: through tracking the coal flow, it can be judged whether there is coal blocking phenomenon on the belt conveyor, when the tracked coal flow reaches the next coal flow detection point, the next coal flow detection point to no coal, the system will issue a coal blocking alarm, and the system is stopped at the same time.

[0099] b) coal stacking early warning: when the coal flow on the belt conveyor is detected or predicted to exceed the rated value, the coal winning machine will be fed back, an alarm will be issued, and the coal winning machine will reduce the mining amount.

[0100] As shown in Figure 7 , it is a schematic diagram of the main coal flow transportation system. Figure 7

[0101] The embodiment of the present application also provides a main coal flow transportation balance control device, which is arranged in a PLC control system; the specific device can include:

[0102] An image acquisition module is used to acquire the surface image of the preset coal flow detection position on the belt conveyor after the structured light irradiation;

[0103] A coal flow detection module is used to extract the cross-sectional area of the coal according to the surface image, and calculate the coal flow in a preset time length in real time;

[0104] A coal flow tracking module is used to divide the belt conveyor into a plurality of regions, value each region by using the real-time collected coal flow, and track the coal flow according to the running speed of the belt conveyor;

[0105] A speed regulation module is used to calculate the speed regulation value according to the tracking information of the coal flow, and send a speed regulation instruction to the belt conveyor.

[0106] The main coal flow transportation balance control device of the embodiment is used to realize the aforementioned main coal flow transportation balance control method, so the specific embodiments in the main coal flow transportation balance control device can be seen from the embodiment part of the main coal flow transportation balance control method, for example, the image acquisition module, the coal flow detection module, the coal flow tracking module and the speed regulation module are respectively used to realize steps S101, S102, S103, S104 and S105 in the aforementioned main coal flow transportation balance control method, so the specific embodiments can refer to the description of the corresponding part of the embodiment, and will not be repeated here.

[0107] The embodiment of the present application also provides a main coal flow transportation balance control device, which includes a memory for storing a computer program, and a processor for executing the computer program to realize the steps of the aforementioned main coal flow transportation balance control method.

[0108] ​The embodiment of the present application further provides a computer readable storage medium, wherein the computer readable storage medium stores a computer program, and the computer program is executed by a processor to realize the steps of the main coal flow transportation balance control method.

[0109] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. In addition, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage and the like) containing computer-usable program code.

[0110] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems) and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate a device implemented in the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that carries out the functions specified in one or more flows and / or blocks.

[0111] These computer program instructions can also be stored in a computer readable memory that can direct the computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including instruction apparatus, which realizes the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that carries out the functions specified in one or more flows and / or blocks.

[0112] These computer program instructions can also be loaded into a computer or other programmable data processing device, so that a series of operation steps are performed on the computer or other programmable device to produce a computer implemented process, so that the instructions executed on the computer or other programmable device provide a process for realizing the flowcharts and / or block diagrams. Figure 1 one or more flows and / or blocks Figure 1 an apparatus that carries out the functions specified in one or more flows and / or blocks.

[0113] Obviously, the above embodiments are merely example for clearly illustrating, and are not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be enumerated, and the obvious changes or variations derived from the above are still within the protection scope of the present application.

Claims

1. A method for balanced control of main coal flow transportation, characterized in that, include: A surface image of a preset coal flow detection position on a belt conveyor is obtained after structured light illumination. The preset coal flow detection position is set at a preset distance from the tail of the next-stage belt conveyor. The preset distance is calculated based on the current rated speed of the belt conveyor, the acceleration time set by the frequency converter of the next-stage belt conveyor, the rated frequency of the motor of the next-stage belt conveyor, the braking safety distance, and the coal flow detection distance. The cross-sectional area of ​​the coal is extracted from the surface image, and the coal flow rate within a preset time period is calculated in real time. The belt conveyor is divided into several areas, and the coal flow rate collected in real time is used to assign a value to each area. The coal flow rate is also tracked according to the operating speed of the belt conveyor. Based on the coal flow tracking information, a speed adjustment value is calculated, and a speed adjustment command is sent to the belt conveyor. If the speed adjustment command is to increase speed, the speed of the next-level belt conveyor is increased before the coal flow increases and before it reaches the next-level belt conveyor. If the speed adjustment command is to decrease speed, the belt speed is not adjusted when the coal flow decreases and before it reaches the current-level belt conveyor. The speed of the current-level belt conveyor is then decreased after a second response time delay.

2. The method for balanced control of main coal flow transportation according to claim 1, characterized in that, The step of extracting the cross-sectional area of ​​the coal based on the surface image and calculating the coal flow rate within a preset time period in real time includes: The coal flow rate within a preset time period is calculated in real time based on the image acquisition time interval, the cross-sectional area of ​​the coal, the real-time belt speed, and the coal density.

3. The method for balanced control of main coal flow transportation according to claim 1, characterized in that, The sending of speed control commands to the belt conveyor includes: When the speed regulation value is different from the actual belt speed, and the speed regulation value is the same after multiple consecutive calculations, a speed regulation command is sent to the belt conveyor.

4. The method for balanced control of main coal flow transportation according to claim 1, characterized in that, The step of calculating the speed regulation value based on the coal flow tracking information and sending a speed regulation command to the belt conveyor includes: When the coal flow rate is detected or predicted to be no greater than the first threshold, and there is no coal flow rate exceeding the first threshold on the current belt conveyor after a third response delay, a low-speed mode command is issued. When the coal flow rate is detected or predicted to be greater than the first threshold and not greater than the second threshold, a medium-speed mode command is issued. When the coal flow rate is detected or predicted to be greater than the second threshold, a high-speed mode command is issued. When the coal flow rate is detected or predicted to be greater than the second threshold, and after a fourth response delay, there is no coal flow rate on the current belt conveyor that exceeds the second threshold, a medium-speed mode command is issued.

5. The method for balanced control of main coal flow transportation according to claim 1, characterized in that, Also includes: When the tracked coal flow reaches the next coal flow detection point, and there is no coal at the next coal flow detection point, A coal blockage alarm is issued, and the system is simultaneously shut down.

6. The method for balanced control of main coal flow transportation according to claim 1, characterized in that, Also includes: When the coal flow rate on the belt conveyor is detected or predicted to exceed the rated value, a coal pile-up alarm is issued, and the coal mining machine is simultaneously activated to reduce the mining volume.

7. A main coal flow transport balancing control device, characterized in that, The main coal flow transportation balance control method according to any one of claims 1-6 includes: The image acquisition module is used to acquire surface images of the preset coal flow detection positions on the belt conveyor after structured light illumination; The coal flow detection module is used to extract the cross-sectional area of ​​the coal based on the surface image and calculate the coal flow rate within a preset time period in real time. The coal flow tracking module is used to divide the belt conveyor into several areas, assign a value to each area using the real-time collected coal flow, and track the coal flow according to the operating speed of the belt conveyor. The speed control module is used to calculate the speed control value based on the coal flow tracking information and send speed control commands to the belt conveyor.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the main coal flow transportation balance control method as described in any one of claims 1 to 6.

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