A Smart Anti-blocking Control Method for Coal Chute Based on Multi-Source Sensing and Optimal Control

Abstract

This invention discloses an intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control, relating to the field of coal chute anti-blocking technology, including the following steps: determining the blockage state C of the coal chute. i (t); Determine the priority order for clearing blockages in the coal chute, prioritizing the clearing of blockages in lower layers; Obtain the minimum input combination through an integral objective function to obtain the optimal control input combination for alternating control of the air hammer A in the corresponding layer. i With pneumatic fluidizing nozzle F i Perform a congestion clearing operation; construct a priority queue Q(t) and sort it according to the layer number in ascending order to implement the "first-in, first-out" scheduling principle, and execute the congestion clearing operation; when x i If (t+30s) = 1, indicating a failure to clear the blockage, an alarm signal B(t) is activated. If no manual intervention is performed within 15 minutes, the blockage clearing task for that layer is automatically restarted. This invention enables dynamic coordinated control of the air hammer and the pneumatic fluidization blockage clearing device, minimizing the duration of coal blockage and energy consumption, and improving blockage clearing efficiency.

Description

Technical Field

[0001] This invention relates to the field of coal chute anti-blocking technology, and in particular to an intelligent anti-blocking control method for coal chute based on multi-source sensing and optimal control. Background Technology

[0002] The coal chute is an important component of the coal conveying system in a thermal power plant. It is responsible for smoothly conveying pulverized coal from the upper coal bunker to the coal feeder or coal mill. During operation, due to uneven coal particle size, high moisture content, unstable coal dropping speed, or adhesion points on the pipe wall structure, coal powder is prone to accumulation and blockage, which can seriously affect the safe operation of the entire unit.

[0003] Currently, the following anti-blockage and clearing control technologies are mainly used to address the problem of coal chutes blockage: (1) Timed clearing control technology: The air hammer or pneumatic nozzle is automatically activated according to the set cycle, and the clearing action is performed in time sequence regardless of whether a blockage occurs. This method has a simple control structure, is easy to implement, and has a low cost. The disadvantage is that it cannot perceive the real-time blockage status, which can easily lead to resource waste, and the response is delayed in the event of a sudden blockage. (2) Manual clearing control technology: It relies on manual observation of the coal chutes status and activates the clearing device through the control button when necessary. This method is flexible and suitable for on-site duty scenarios. The disadvantage is that it relies on manual judgment, the response is not timely, the manual labor intensity is high, there is a risk of misjudgment or omission, and it is not suitable for automated and remote control scenarios. (3) Single sensor automatic control technology: The coal powder flow status is monitored in real time through a single-point coal flow detector to determine whether there is a blockage and automatically start the corresponding layer air hammer. This method can automatically respond to blockages, improve efficiency, and achieve local automation. The disadvantage is that the information source is single, it is easily affected by false signals, it cannot judge multiple concurrent blockages or clearing priorities, and it lacks hierarchical coordination and scheduling capabilities. (4) Linked control system without optimal strategy: Some systems support the linked operation of air hammers and pneumatic fluidization devices, but the control strategy is based on rule judgment and lacks optimization support. The disadvantages are the lack of an optimal scheduling model, the inability to adjust the control strategy, and low processing efficiency when facing multi-layer blockages. Therefore, existing technologies have the following shortcomings: lack of multi-source perception and fusion of coal flow status; inability to dynamically decide the blockage clearing sequence and execution rhythm; lack of a global optimal control strategy to achieve minimum energy consumption and shortest blockage clearing time; imperfect alarm and reset mechanisms, and limited system stability and intelligence level. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control.

[0005] The technical solution adopted to solve the above-mentioned technical problems is: an intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control, including the following steps:

[0006] S1. Divide each coal chute into multiple layers from top to bottom, designating the top layer as the first layer, and install an air hammer A in each layer. i (i = 1, ..., m) and coal flow detector C i (i = 1, ..., m), air hammer A i Coal flow detector C is used to clear blockages in the coal chute. i Used for continuous monitoring of the flow rate within the coal chutes; each layer within each coal chute is equipped with a pneumatic fluidization nozzle F. i (i = 1, ..., n) and pressure sensor P i (i = 1, ..., n), pneumatic fluidizing nozzle F i Pressure sensor P is used to clear blockages in the coal chute. i Used to assist in judging the pneumatic fluidization nozzle F i Whether it is blocked; according to the coal flow detector C i Signal, pneumatic fluidizing nozzle F i and pressure sensor P i The signal is used to determine the blockage status of the coal chute C. i (t);

[0007] S2. When multiple layers of blockage occur simultaneously in the coal chute, determine the priority order for clearing blockages in the coal chute, prioritizing the clearing of lower-level blockages to prevent blockages from accumulating.

[0008] S3. The control process is mathematically modeled by constructing an integral objective function, with the control variables including the air hammer excitation. Pneumatic fluidizing nozzle excitation and coal flow state x i (t), when the coal flow detector C i When a continuous blockage signal is detected for ≥2 seconds, the blockage status x of the coal chute is determined. i (t) represents congestion. The minimum input combination is obtained through the integral objective function, thus obtaining the optimal control input combination. Alternately control the air hammer A on the corresponding layer i With pneumatic fluidizing nozzle F i Perform the blockage clearing operation;

[0009] S4, according to x i A priority queue Q(t) is constructed at the level of (t) = 1, and sorted in ascending order of level number to achieve the "first-in, first-out" scheduling principle;

[0010] S5, when x i If (t+30s) = 1, meaning the blockage clearing fails, then alarm signal B(t) is activated, and the alarm log is recorded. If no manual intervention is performed within 15 minutes, the blockage clearing task for that layer will be automatically restarted.

[0011] Furthermore, the blockage state C of the coal chute in S1 i The method for determining (t) is as follows:

[0012] C i (t)=λ1F i (t)+λ2P i (t)+λ3ΔP i (t)

[0013] In the above formula, F i (t) represents the coal flow detection signal, P i (t) is the normalized value of the pressure sensor, ΔP i (t) represents the rate of change of pressure, and λ1, λ2, and λ3 are weighting coefficients, with λ1 being 0.6, λ2 being 0.3, and λ3 being 0.1.

[0014] When C i If (t) > 0.8 and lasts for 2 seconds, the coal chute is determined to be blocked.

[0015] Furthermore, the method for determining the priority order of unblocking processes in S2 is as follows:

[0016] Set the base priority W i :

[0017]

[0018] In the above formula, i is the current level code, when i=1 is the top level, and N is the total number of coal chutes;

[0019] Using the congestion severity factor S i Quantify the severity of the current congestion by integrating information from both traffic and pressure dimensions:

[0020] S i =0.7F i (t)+0.3P i (t)

[0021] By weighted fusion basic priority W i and the severity factor S of the blockage i Generate the overall priority R i :

[0022] R i =0.4W i +0.6S i .

[0023] Furthermore, the integral objective function J in S3 is:

[0024]

[0025] In the above formula, minJ is the minimum integral objective function, T is the minimum unblocking time, α is the power consumption coefficient of the air hammer, and m is the total number of air hammers. For air hammer excitation, This indicates whether the air hammer of the i-th layer is activated, with 1 indicating activation and 0 indicating deactivation. β is the power consumption coefficient of the pneumatic fluidizing nozzle, and n is the total number of pneumatic fluidizing nozzles. For excitation of the pneumatic fluidizing nozzle, u F j (t)∈{0,1} indicates whether the j-th layer of pneumatic fluidization nozzle is activated, 1 for activation, 0 for inactivation, γ is the clogging penalty factor, p represents the total number of layers in the coal chute, and x i (t) represents the coal flow state, x i (t)∈{0,1} indicates whether the i-th layer of coal flow is blocked, 1 indicates blockage, 0 indicates unobstructed flow, and dt represents the small change of variable t during the integration process.

[0026] Furthermore, the dynamic update method of the α, β adaptive strategy is as follows:

[0027]

[0028] In the above formula, k is the adjustment coefficient, k = 0.2, N c (t) represents the number of layers blocked in the coal chute at the current moment, m represents the total number of layers blocked by the air hammer, and T represents the number of layers blocked. clear (t) represents the unblocking time of the current layer in the coal chute, T max This is the maximum time threshold for clearing congestion.

[0029] Furthermore, the priority queue Q(t) in S4 is:

[0030] Q(t) = sorted({i,x) i (t)=1})

[0031]

[0032] In the above formula, sorted represents the sorting from top to bottom according to the comprehensive priority, i is the current level code, and x i (t) represents the coal flow state, t d x represents the duration of consecutive congestion signals. i (t)∈{0,1} indicates whether the coal flow in the i-th layer is blocked, where 1 indicates blockage and 0 indicates unobstructed flow;

[0033] Each control cycle is as follows: air hammer activation for 1 second, wait for 1 second, pneumatic fluidizing nozzle activation for 2 seconds, wait for 2 seconds, and repeat this operation.

[0034] The beneficial effects of the present invention are as follows: (1) The present invention determines the priority order of clearing blockages in the coal chute, prioritizes clearing blockages in the lower layer, obtains the minimum input combination through an integral objective function, and obtains the optimal control input combination. Alternately control the air hammer A on the corresponding layer i With pneumatic fluidizing nozzle F i Perform blockage clearing operations; construct a priority queue Q(t) and sort it according to the layer number from smallest to largest to achieve the "first-in, first-out" scheduling principle, realize accurate blockage identification and automated blockage clearing response, and realize dynamic collaborative control of air hammer and pneumatic fluidization blockage clearing device, minimize the duration of coal blockage and energy consumption, and improve blockage clearing efficiency.

[0035] (2) This invention combines multi-source sensing with optimal control to achieve accurate identification and efficient unblocking of the coal chute blockage, significantly improving the system's intelligence level. Compared with traditional timed or manual control methods, this method offers more timely response, more thorough unblocking, and lower energy consumption. This invention also possesses advantages such as adaptive scheduling, automatic alarm, and multi-mode fusion, effectively ensuring the continuous and stable operation of the coal conveying system. Attached Figure Description

[0036] Figure 1 This is a flowchart of the intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to the present invention.

[0037] Figure 2 This is a structural diagram of the perception layer, execution layer, and control layer in this embodiment. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0039] like Figures 1 to 2 As shown in the figure, the intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control in this embodiment includes the following steps:

[0040] S1. Divide each coal chute into multiple layers from top to bottom, designating the top layer as the first layer, which includes a sensing layer, an execution layer, and a control layer. Install an air hammer A in each layer. i (i = 1, ..., m) and coal flow detector C i (i = 1, ..., m), air hammer A i Coal flow detector C is used to clear blockages in the coal chute. i Used for continuous monitoring of the unobstructed flow within the coal chute.

[0041] Each layer of each coal chute is equipped with a pneumatic fluidization nozzle F.i (i = 1, ..., n) and pressure sensor P i (i = 1, ..., n), pneumatic fluidizing nozzle F i Pressure sensor P is used to clear blockages in the coal chute. i Used to assist in judging the pneumatic fluidization nozzle F i Is it blocked?

[0042] According to coal flow detector C i Signal, pneumatic fluidizing nozzle F i and pressure sensor P i The signal is used to determine the blockage status of the coal chute C. i (t).

[0043] C of the coal chute blockage i The method for determining (t) is as follows:

[0044] C i (t)=λ1F i (t)+λ2P i (t)+λ3ΔP i (t)

[0045] In the above formula, F i (t) represents the coal flow detection signal, P i (t) is the normalized value of the pressure sensor, ΔP i (t) represents the rate of change of pressure, and λ1, λ2, and λ3 are weighting coefficients, with λ1 being 0.6, λ2 being 0.3, and λ3 being 0.1.

[0046] When C i If (t) > 0.8 and lasts for 2 seconds, the coal chute is determined to be blocked.

[0047] S2. When multiple layers of blockage occur simultaneously in the coal chute, determine the priority order for clearing blockages in the coal chute, prioritize clearing blockages in the lower layers to prevent blockages from accumulating, and follow the principle of "coal powder gravity discharge first".

[0048] The method for determining the priority of clearing blockages is as follows:

[0049] Set the base priority W i :

[0050]

[0051] In the above formula, i is the current level code, when i=1 is the top level, and N is the total number of coal chutes;

[0052] Using the congestion severity factor S i Quantify the severity of the current congestion by integrating information from both traffic and pressure dimensions:

[0053] S i =0.7F i (t)+0.3P i (t)

[0054] By weighted fusion basic priority W i and the severity factor S of the blockage i Generate the overall priority R i :

[0055] R i =0.4W i +0.6S i .

[0056] S3. The control process is mathematically modeled by constructing an integral objective function, with the control variables including the air hammer excitation. Pneumatic fluidizing nozzle excitation and coal flow state x i (t), coal flow detector C i When a continuous blockage signal is detected for ≥2 seconds, the blockage status x of the coal chute is determined. i (t) represents congestion. The minimum input combination is obtained through the integral objective function, thus obtaining the optimal control input combination. Alternately control the air hammer A on the corresponding layer i With pneumatic fluidizing nozzle F i Perform the blockage clearing operation.

[0057] The integral objective function J is:

[0058]

[0059] In the above formula, minJ is the minimum integral objective function, T is the minimum unblocking time (T = 30s), α is the power consumption coefficient of the air hammer, and m is the total number of air hammers. For air hammer excitation, This indicates whether the air hammer of the i-th layer is activated, with 1 indicating activation and 0 indicating deactivation. β is the power consumption coefficient of the pneumatic fluidizing nozzle, and n is the total number of pneumatic fluidizing nozzles. Excitation for pneumatic fluidizing nozzles. This indicates whether the pneumatic fluidization nozzle at the j-th layer is activated, with 1 for activated and 0 for inactive. γ is the clogging penalty factor, where γ = 10. p represents the total number of layers in the coal chute, and x... i (t) represents the coal flow state, x i (t)∈{0,1} indicates whether the i-th layer of coal flow is blocked, 1 indicates blockage, 0 indicates unobstructed flow, and dt represents the small change of variable t during the integration process.

[0060] The α and β adaptive policy is updated dynamically as follows:

[0061]

[0062] In the above formula, k is the adjustment coefficient, k = 0.2, N c (t) represents the number of layers blocked in the coal chute at the current moment, m represents the total number of layers blocked by the air hammer, and T represents the number of layers blocked. clear (t) represents the unblocking time of the current layer in the coal chute, T max This is the maximum time threshold for clearing congestion.

[0063] This embodiment can dynamically adapt to different blockage scenarios in the coal chute, enhancing the system's clearing efficiency and economy under complex working conditions.

[0064] S4, according to x i A priority queue Q(t) is constructed with a hierarchy of (t) = 1, and sorted in ascending order of hierarchy number to achieve the "first-in, first-out" scheduling principle.

[0065] In S4, the priority queue Q(t) is:

[0066] Q(t) = sorted({i,x) i (t)=1})

[0067]

[0068] In the above formula, sorted represents the sorting from top to bottom according to the comprehensive priority, i is the current level code, and x i (t) represents the coal flow state, t d x represents the duration of consecutive congestion signals. i (t)∈{0,1} indicates whether the coal flow in the i-th layer is blocked, where 1 indicates blockage and 0 indicates unobstructed flow.

[0069] The following sequence of clearing instructions is executed in the queue:

[0070]

[0071] Each control cycle consists of: 1 second for air hammer activation, 1 second wait, 2 seconds for fluidizing nozzle activation, and 2 seconds wait. This cycle is repeated to enhance the unblocking effect and reduce energy consumption.

[0072] S5, when x i If (t+30s) = 1, meaning the blockage clearing fails, then alarm signal B(t) is activated, and the alarm log is recorded. If no manual intervention is performed within 15 minutes, the blockage clearing task for that layer will be automatically restarted.

[0073] In other words, if the congestion clearing operation fails to achieve its target within the set time, the system will trigger an alarm to prompt manual intervention. If there is no response within 15 minutes, the system will restart the automatic congestion clearing process and attempt to recover on its own. This mechanism improves the system's self-recovery capability in unattended operation.

[0074] This embodiment achieves closed-loop operation of the entire process of blockage identification, priority scheduling, intelligent control, and fault-tolerant recovery through the above steps, which significantly enhances the efficiency of coal flow clearing and the intelligence level of the control system.

[0075] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A method for intelligent anti-blocking control of coal chutes based on multi-source sensing and optimal control, characterized in that, Includes the following steps: S1. Divide each coal chute into multiple layers from top to bottom, designating the top layer as the first layer, and install an air hammer A in each layer. i (i = 1, ..., m) and coal flow detector C i (i = 1, ..., m), air hammer A i Coal flow detector C is used to clear blockages in the coal chute. i Used for continuous monitoring of the unobstructed flow within the coal chute; Each layer of each coal chute is equipped with a pneumatic fluidization nozzle F. i (i = 1, ..., n) and pressure sensor P i (i = 1, ..., n), pneumatic fluidizing nozzle F i Pressure sensor P is used to clear blockages in the coal chute. i Used to assist in judging the pneumatic fluidization nozzle F i Is it blocked? According to coal flow detector C i Signal, pneumatic fluidizing nozzle F i and pressure sensor P i The signal is used to determine the blockage status of the coal chute C. i (t); S2. When multiple layers of blockage occur simultaneously in the coal chute, determine the priority order for clearing blockages in the coal chute, prioritizing the clearing of lower-level blockages to prevent blockages from accumulating. S3. The control process is mathematically modeled by constructing an integral objective function, with the control variables including the air hammer excitation. Pneumatic fluidizing nozzle excitation and coal flow state x i (t), when the coal flow detector C i When a continuous blockage signal is detected for ≥2 seconds, the blockage status x of the coal chute is determined. i (t) represents congestion. The minimum input combination is obtained through the integral objective function, thus obtaining the optimal control input combination. Alternately control the air hammer A on the corresponding layer i With pneumatic fluidizing nozzle F i Perform the blockage clearing operation; S4, according to x i A priority queue Q(t) is constructed at the level of (t) = 1, and sorted in ascending order of level number to achieve the "first-in, first-out" scheduling principle; S5, when x i If (t+30s) = 1, meaning the blockage clearing fails, then alarm signal B(t) is activated, and the alarm log is recorded. If no manual intervention is performed within 15 minutes, the blockage clearing task for that layer will be automatically restarted.

2. The intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to claim 1, characterized in that: The blockage state C of the coal chute in S1 i The method for determining (t) is as follows: C i (t)=λ1F i (t)+λ2P i (t)+λ3ΔP i (t) In the above formula, F i (t) represents the coal flow detection signal, P i (t) is the normalized value of the pressure sensor, ΔP i (t) represents the rate of change of pressure, and λ1, λ2, and λ3 are weighting coefficients, with λ1 being 0.6, λ2 being 0.3, and λ3 being 0.

1. When C i If (t) > 0.8 and lasts for 2 seconds, the coal chute is determined to be blocked.

3. The intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to claim 1, characterized in that: The method for determining the priority order of unblocking processes in S2 is as follows: Set the base priority W i : In the above formula, i is the current level code, when i=1 is the top level, and N is the total number of coal chutes; Using the congestion severity factor S i Quantify the severity of the current congestion by integrating information from both traffic and pressure dimensions: S i =0.7F i (t)+0.3P i (t) By weighted fusion basic priority W i and the severity factor S of the blockage i Generate the overall priority R i : R i =0.4W i +0.6S i 。 4. The intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to claim 1, characterized in that: The integral objective function J in S3 is: In the above formula, minJ is the minimum integral objective function, T is the minimum unblocking time, α is the power consumption coefficient of the air hammer, and m is the total number of air hammers. For air hammer excitation, u A i (t)∈{0,1} indicates whether the air hammer of the i-th layer is activated, 1 for activation and 0 for deactivation, β for power consumption coefficient of the pneumatic fluidizing nozzle, and n for the total number of pneumatic fluidizing nozzles. For excitation of the pneumatic fluidizing nozzle, u F j (t)∈{0,1} indicates whether the j-th layer of pneumatic fluidization nozzle is activated, 1 for activation, 0 for inactivation, γ is the clogging penalty factor, p represents the total number of layers in the coal chute, and x i (t) represents the coal flow state, x i (t)∈{0,1} indicates whether the i-th layer of coal flow is blocked, 1 indicates blockage, 0 indicates unobstructed flow, and dt represents the small change of variable t during the integration process.

5. The intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to claim 4, characterized in that: The dynamic update method of the α, β adaptive strategy is as follows: In the above formula, k is the adjustment coefficient, k = 0.2, N c (t) represents the number of layers blocked in the coal chute at the current moment, m represents the total number of layers blocked by the air hammer, and T represents the number of layers blocked. clear (t) represents the unblocking time of the current layer in the coal chute, T max This is the maximum time threshold for clearing congestion.

6. The intelligent anti-blocking control method for coal chutes based on multi-source sensing and optimal control according to claim 1, characterized in that: The priority queue Q(t) in S4 is as follows: Q(t)=sorted({i,x i (t)=1}) In the above formula, sorted represents the sorting from top to bottom according to the comprehensive priority, i is the current level code, and x i (t) represents the coal flow state, t d x represents the duration of consecutive congestion signals. i (t)∈{0,1} indicates whether the coal flow in the i-th layer is blocked, where 1 indicates blockage and 0 indicates unobstructed flow; Each control cycle is as follows: air hammer activation for 1 second, wait for 1 second, pneumatic fluidizing nozzle activation for 2 seconds, wait for 2 seconds, and repeat this operation.

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