Branch risk window and dust cleaning and cashing dedusting energy-saving control method and system

Abstract

The application discloses a branch risk window and ash cleaning and dust removal energy-saving control method and system, and relates to the technical field of industrial dust removal and energy-saving control. The method collects dust production branch, dust remover filter chamber, ash cleaning gas supply, fan and safety interlocking information, and generates a branch deposition risk window table; according to the window table, the branch state is divided, and frequency reduction is prohibited when there is an active branch in the state of needing air supplement repair, needing purging or being isolated and locked; an ash cleaning income realization record table and a phased cooperative control instruction sheet are generated; branch repair and ash cleaning are performed first, the frequency is reduced within the time limit and amplitude at the boundary, and the frequency and write-back parameters are maintained, locked or rolled back according to the observation window result. The application integrates branch risk, ash cleaning and realization and safety interlocking into the same control link, and realizes safe and energy-saving operation of the powder production line dust removal system.

Description

Technical Field

[0001] This invention belongs to the field of industrial dust removal and energy-saving control technology, specifically relating to a branch risk window and dust removal energy-saving control method and system. Background Technology

[0002] Powder production lines generate significant amounts of dust during processes such as feeding, mixing, screening, pneumatic conveying, and packaging. This dust is typically collected from multiple dust-generating branches using a centralized dust collection system. After purification by bag filters or cartridge filters, the dust is discharged into the atmosphere by a variable frequency fan. Over time, the pressure differential in the filter chambers increases, requiring compressed air pulse cleaning to restore permeability. In this system, the branch airflow is affected by multiple factors, including the start / stop of dust-generating equipment, valve opening, pipeline resistance, and fan frequency. Lowering the fan frequency offers energy savings, but it is crucial to ensure that each dust-generating branch meets safety boundaries for collection, conveying, and preventing sediment buildup.

[0003] In related technologies, existing dust removal energy-saving control usually adopts the following methods: First, the fan frequency is adjusted according to the main static pressure or total air volume. However, when the main static pressure is normal, some branches may already have insufficient air volume due to the position of the air valve or local blockage. Continuing to reduce the frequency can easily lead to dust leakage from the hood and dust accumulation in the pipeline. Second, dust removal is performed according to a fixed time or fixed pressure difference. The branch window status and fan frequency reduction space are not considered after dust removal. The decrease in filter chamber pressure difference does not necessarily translate into fan energy saving. Ineffective blowing will increase compressed air energy consumption and filter material burden. Third, the air valve adjustment, dust removal and frequency reduction operations are independent open-loop actions, lacking a unified execution sequence and backoff mechanism. It is easy for the energy-saving action to fail due to the risk of a certain branch. Moreover, there is no observation, verification and cause writing, making it difficult to form closed-loop control.

[0004] Therefore, there is an urgent need for a branch risk window and a dust removal energy-saving control method and system that realizes dust removal benefits. This method and system can dynamically identify the safety boundaries of each branch by establishing a branch deposition risk window table, determine whether dust removal can be converted into fan energy saving by using a dust removal benefit realization record table, and uniformly constrain the execution sequence and verification rollback of valve repair, dust removal and frequency reduction release by a phased collaborative control instruction sheet. This will solve the technical problems of invisible branch risks, unrealized dust removal energy saving, fragmented action sequence and lack of closed-loop feedback in the existing dust removal control. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art by providing a branch risk window and dust removal energy-saving control method and system. The branch risk window and dust removal energy-saving control method realizes dynamic identification and gating of branch-level risks, quantitative assessment and verification of dust removal benefits, and phased coordinated control and closed-loop feedback correction of valve repair, dust removal and fan frequency reduction.

[0006] To solve the above problems, the first aspect of the present invention adopts the following technical solution: A method for controlling the risk window of a branch circuit and the dust removal and energy saving of the dust removal process includes the following steps: Step 1: Collect operational information on multiple dust-generating branches, dust collector filter chambers, dust removal air supply, fans, and safety interlocks in the powder production line, and generate a branch deposition risk window table; the branch deposition risk window table shall at least record the minimum required air volume, current branch air volume, low wind speed duration, residual powder load, dust compatibility mark, data reliability, and transferable air volume of the corresponding dust-generating branch. Step 2: According to the branch deposition risk window table, each dust-generating branch is divided into at least one of the following window states: safe transferable state, restricted transferable state, need for supplemental air repair state, need for purging state, and isolation and locking state. When any active dust-generating branch is in the need for supplemental air repair state, need for purging state, or isolation and locking state, energy-saving actions that reduce the frequency of the fan are prohibited. Step 3: Generate a dust removal benefit realization record table based on filter chamber operation information, dust removal air supply information, and fan operation information. Then, generate a phased collaborative control instruction sheet under the joint constraints of the branch deposition risk window table and the dust removal benefit realization record table. The dust removal benefit realization record table should at least record the dust layer increment resistance of the candidate filter chamber, the expected dust removal fall-off amount, the realizeable fan frequency reduction amount, and the expected fan power reduction amount. The phased collaborative control instruction sheet should at least include branch repair actions, dust removal actions, and fan frequency release actions, and their execution order. Step 4: Perform the branch repair and dust removal actions first, following the execution order. When the branch window boundary and safety interlock conditions are met, release the fan frequency reduction according to the available fan frequency reduction limit, and verify the branch air volume, filter chamber pressure difference, and actual fan power reduction in the corresponding observation window. If the verification is successful, maintain the frequency reduction; otherwise, lock or revert the fan frequency. Step 5: Write back and update the branch parameters and dust removal fulfillment rate based on the verification results, and switch to conservative control mode when the safety interlock is abnormal.

[0007] Furthermore, in step one, the minimum required air volume of the i-th dust-generating branch is determined by multiplying the maximum value among the air volume required for hood capture, the air volume corresponding to the minimum conveying air velocity in the pipeline, and the required air volume for purging by a margin coefficient, and then adding it to the maintenance air volume.

[0008] Furthermore, in step one, when no direct airflow timer is set in the dust-generating branch, the current branch airflow is estimated based on the branch pressure difference signal, branch damper opening, gas density, and branch calibration coefficient; the branch calibration coefficient is recursively corrected based on the measured wind speed, branch pressure change, damper opening change, and fan frequency change in the observation window.

[0009] Furthermore, in step one, the low wind speed duration is accumulated according to the control cycle when the current branch wind speed is lower than the minimum delivery wind speed, and decays or is cleared to zero after the branch wind speed recovers or a purging action is performed; the low wind speed duration is used to trigger the purging state and limit the fan frequency reduction action.

[0010] Furthermore, in step one, the low wind speed duration and residual dust load are jointly mapped to a first air volume deduction value, and the data reliability is mapped to a second air volume deduction value. The safety margin, the first air volume deduction value, and the second air volume deduction value are deducted sequentially from the difference between the current branch air volume and the minimum required air volume to determine the transferable air volume. Only dust-generating branches in a safe and transferable state are allowed to participate in the fan frequency reduction.

[0011] Furthermore, in step two, the dust compatibility mark is determined by at least one of dust category, shared pipeline permission, explosion risk, pollution risk, and recycling strategy; when the dust compatibility mark is prohibited from sharing or prohibited from linkage, the corresponding dust-generating branch is classified as an isolated and locked state, and does not participate in the linkage frequency reduction or the realization of joint dust removal benefits.

[0012] Furthermore, in step three, the feasible fan frequency reduction amount for the candidate filter chamber is determined as follows: under the expected resistance state after the candidate filter chamber is cleaned, the maximum fan frequency reduction amount that will not cause any active dust-generating branch to fall out of the branch deposition risk window surface boundary is calculated; when there is no fan frequency reduction amount that meets the conditions, or the maximum fan frequency reduction amount is lower than the frequency reduction release threshold, or the energy consumption of the compressed air is higher than the expected fan energy saving, the unnecessary cleaning action of the candidate filter chamber is temporarily suspended.

[0013] Furthermore, in step three, the conditions for realizing the dust removal benefits include: the incremental resistance of the dust layer in the candidate filter chamber is higher than the dust removal candidate threshold, the expected dust removal fall-off amount is higher than the fall-off threshold, the compressed air pressure meets the injection requirements, the energy consumption of the injection compressed air is lower than the expected fan energy saving, the outlet dust pulse risk is lower than the risk threshold, and the expected fan frequency reduction amount that can be realized after dust removal is not lower than the frequency reduction release threshold.

[0014] Furthermore, in step four, if the filter chamber pressure difference decreases after cleaning but the actual fan power decrease does not fall within the expected power decrease range corresponding to the achievable fan frequency reduction, then the cleaning is recorded as resistance reduction not achieved; if the filter chamber pressure difference decreases insufficiently after cleaning, it is recorded as cleaning ineffective; if the outlet dust increases after cleaning, it is recorded as cleaning disturbance risk; and the cleaning achievement rate is updated based on the achieved records, non-achievable reason codes, actual fan power decrease, and expected fan power decrease.

[0015] The second aspect of this invention adopts the following technical solution: A branch risk window and dust removal energy-saving control system includes: The dust generation status acquisition module is used to collect information on multiple dust generation branches, dust collector filter chambers, dust removal air supply, fans, and safety interlocks. The branch deposition risk window module is used to generate and update the branch deposition risk window table for each dust-generating branch, and output the window status and allowable air volume for each dust-generating branch. The dust removal revenue realization module is used to generate a dust removal revenue realization record table and determine the dust removal action, dust removal suspension action, realizeable fan frequency reduction amount, expected fan power reduction amount, and candidate ranking based on the dust removal realization rate for candidate filter chambers. The phased instruction sheet generation module is used to generate phased collaborative control instruction sheets containing branch repair, purging, dust removal and fan frequency release actions based on the branch deposition risk window table and the dust removal revenue realization record table. The local execution module is used to send the phased collaborative control instruction sheet to the frequency converter fan, branch air valve, purging device and dust removal pulse valve group; The verification and write-back module is used to verify the branch air volume, filter chamber pressure difference, fan power, jetting air consumption, outlet dust and safety interlock status in the observation window, and write back the branch air volume estimation coefficient, residual powder load, low wind speed duration, deviation between actual and expected fan power reduction and dust removal fulfillment rate. The safety degradation module is used to switch to conservative control mode when the safety interlock fails.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention collects operational information from multiple dust-generating branches and dust collector filter chambers in a powder production line, generating a branch deposition risk window table. It integrates hood capture, pipe-side deposition prevention, residual powder purging, dust compatibility, and data reliability into a branch-level dynamic boundary, avoiding the problem of neglecting low-speed powder accumulation in local branches while relying solely on main pipe static pressure or total airflow adjustment. Based on this, the invention uses a phased collaborative control command sheet to execute control actions in a fixed sequence: "branch window repair → filter chamber cleaning → fan frequency reduction release." An observation window is set up at each stage for verification, ensuring that energy-saving actions have a clear execution sequence, prohibition conditions, and retreat boundaries. This solves the problems of existing methods where fan frequency reduction and cleaning actions are disconnected and lack execution sequence constraints.

[0017] This invention uses a dust removal benefit realization record table to link filter chamber resistance reduction, compressed air consumption for blowing, outlet dust pulse risk, realized fan frequency reduction, and expected fan power reduction. Under the constraint of the branch deposition risk window, it calculates the maximum fan frequency reduction that will not cause any active branch to fall out of the safety boundary. Only when the expected resistance reduction after dust removal can be realized as a fan frequency reduction or power reduction within the branch window boundary, and the compressed air energy consumption and dust pulse risk meet the conditions, is dust removal given priority. This reduces ineffective blowing that is based solely on filter chamber pressure difference and cannot be converted into fan energy saving.

[0018] This invention verifies the branch repair effect through a first observation window and the dust removal fulfillment effect through a second observation window. It can distinguish between different results such as dust removal fulfillment, resistance reduction failure, ineffective dust removal, dust removal disturbance risk, and safety interlock interruption. It also writes back the branch airflow estimation coefficient, low wind speed duration, residual powder load, dust removal fulfillment rate, and failure reason code. Filters with high fulfillment rates are given higher candidate ranking in subsequent similar operating conditions, while filter rooms with low fulfillment rates and repeated failure reasons are temporarily suspended from dust removal or trigger maintenance prompts. Simultaneously, this invention uses safety interlocks such as dust category compatibility, ash hopper discharge, explosion-proof isolation, temperature sparks, outlet dust, and data reliability as hard constraints to ensure that dust removal and energy-saving control in powder production lines does not exceed the safety boundaries of collection, anti-deposition, emission, and combustible dust. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the branch risk window and dust removal revenue realization energy-saving control system of the present invention; the diagram shows the relationship between the dust-generating branch, branch air valve, dust collector, variable frequency fan, dust removal air supply and controller, and shows the branch deposition risk window table and dust removal revenue realization record table. Figure 2 This is a schematic representation of the branch risk window and the branch deposition risk window of the dust removal and energy-saving control method of the present invention; it shows the relationship between minimum required air volume, current branch air volume, low wind speed duration, residual powder load, dust compatibility mark, data reliability, window status and transferable air volume. Figure 3 This is a schematic representation of the dust removal benefit realization record of the branch risk window and the dust removal energy-saving control method of the present invention; it shows the relationship between filter chamber resistance increment, expected dust removal fall amount, pulse gas consumption, outlet dust pulse risk, realizeable fan frequency reduction amount, expected fan power reduction amount and realization result. Figure 4 This is a flowchart of the phased collaborative control instruction sheet for the branch risk window and dust removal energy-saving control method of the present invention; it shows the processing link between branch window repair, candidate filter chamber cleaning, fan frequency reduction release, observation and verification, and lockback. Figure 5 This is a schematic diagram of dust compatibility and safety degradation in the branch risk window and dust removal energy-saving control method of the present invention; it shows the relationship between the dust compatibility matrix, the prohibition of sharing mark, the safety interlocking anomaly and the conservative control mode. Detailed Implementation

[0020] The technical solutions of the invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without creative effort are within the scope of the invention.

[0021] In the description of this invention, it should be noted that the terms "above" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience and simplification of the description and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection," "setting," "installation," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] like Figure 1 As shown, this invention provides a branch risk window and dust removal energy-saving control method, applicable to dust removal systems in powder production lines that include multiple dust-generating branches, dust collector filter chambers, dust removal air supply devices, and variable frequency fans. Each dust-generating branch can be connected to a feeding station, unpacking station, mixer, screening machine, buffer bin, pneumatic conveying interface, dispensing port, coating equipment, slitting equipment, grinding equipment, recycling station, or cleaning interface. The dust collector can be a bag filter, cartridge filter, or a combined dust collector with compartment cleaning capabilities.

[0025] The control method of this invention converts the dust generation status data group into a branch deposition risk window table, and then combines it with the dust removal benefit realization record table to generate a phased collaborative control instruction sheet. First, branch repair or purging is executed, then dust removal actions that meet the realization conditions are executed, and finally, when the observation window confirms that each active branch still meets the branch deposition risk window boundary, the fan frequency is reduced; if the boundary is not met, the fan frequency is locked or rolled back and the reason is written back.

[0026] The relationships between input objects, intermediate objects, and output objects at each level of the system are shown in Table 1.

[0027] The branch risk window and dust removal energy-saving control method of the present invention includes the following steps: Step 1: Collect operational information and generate a branch deposition risk window table: The system collects operational information from multiple dust-generating branches and dust collector filter chambers in the powder production line, including: branch operation information (dust-generating equipment status, dust type, branch pressure or branch wind speed, branch valve opening, pipe cross-sectional area, hood status, and branch data reliability); filter chamber operation information (filter chamber differential pressure, air volume distribution, filter media status, outlet dust, and ash hopper level); cleaning air supply information (compressed air pressure, pulse-jet valve status, and pulse-jet air consumption); fan operation information (fan frequency, power, current, main pipe static pressure, and total air volume); and safety interlock information (explosion-proof isolation, temperature, spark detection, maintenance door access, and emergency stop status). This data can be obtained from PLCs, DCSs, edge data acquisition units, frequency converters, differential pressure transmitters, wind speed sensors, dust concentration detectors, level gauges, cleaning controllers, compressed air flow meters, or manually configured data.

[0028] Based on the collected dust generation status data sets, the system generates a branch deposition risk window table. For example... Figure 2 As shown, the branch deposition risk window table differs from the static minimum airflow table. It varies with dust generation status, dust type, pipeline status, residual dust load, duration of low airflow, and data reliability. Each window is used to determine whether the corresponding dust-generating branch can yield airflow and how much airflow can be yielded.

[0029] Typical fields of this window table, Table 2:

[0030] As shown in Table 2, the branch deposition risk window table covers a complete information chain from air volume demand and current status to deposition risk assessment and control action output. It is the core basis for subsequent branch status classification and fan frequency reduction gating.

[0031] The minimum required air volume is determined by the combined requirements of hood capture, in-duct delivery, purging, and maintenance air volume. Its calculation method is as follows: ; in, Indicates the first The minimum required air volume for each dust-generating branch within the current window; Indicates the required air volume for hood capture; Indicates the cross-sectional area of ​​the branch pipe; This indicates the minimum conveying velocity corresponding to the dust type, pipe diameter, and pipe orientation. This indicates the required air volume for purging during standby, batch change, cleaning, or short production stoppages. It represents the dimensionless margin coefficient determined by dust type, operating condition fluctuations, sensor errors, and safety strategies, and is usually not less than 1; This indicates the air volume maintained, which is supplemented by residual powder load, dust compatibility markings, or data reliability. This represents the maximum value operator; This formula is used to determine the minimum required air volume for each branch within the current window based on the dust generation status, serving as a safety boundary for subsequent air volume transfer and fan frequency reduction.

[0032] The current branch air volume can be directly measured by an air volume meter. When no direct air volume meter is installed on the dust-generating branch, it is estimated based on the branch pressure difference signal and the damper opening. ; in, Indicates the first Estimated air volume for each dust-generating branch; This indicates the pressure measurement location, branch resistance, and branch damper opening. The corresponding calibration coefficients; This represents the absolute value of the pressure difference signal in the dust-generating branch; Indicates gas density; This estimate can be recursively corrected by measuring wind speed, pressure changes, valve opening changes, and fan frequency changes in the first or second observation window.

[0033] The low wind speed duration is used to express deposition risk and is accumulated over a control cycle when the current branch wind speed is lower than the minimum delivery wind speed. It is attenuated or reset to zero after the branch wind speed recovers or purging is completed. For the first... Each branch is updated in the following way: ; in, Indicates the first The duration of low wind speed in each control cycle; This represents the dimensionless historical cumulative quantity retention coefficient, which is 1 during the period of low wind speed and a decay value greater than or equal to 0 and less than 1 after the wind speed recovers or the purging is completed. Indicates the first The duration of low wind speed in each control cycle (i.e., the previous control cycle); Indicates the first The branch road in the first The low wind speed indication value for each control cycle is set to 1 when the branch wind speed is lower than the minimum delivery wind speed, and 0 otherwise. This represents the minimum value operator; This indicates the cumulative upper limit of the duration of low wind speed, and... Use the same time unit; Indicates the length of the control cycle; After the branch wind speed recovers or a purging action is performed, through This causes the duration of low wind speed to decay or be reduced to zero. The formula accumulates the low wind speed state over time; the greater the duration of low wind speed, the greater the risk of sedimentation, and the less suitable this branch is for participating in wind turbine frequency reduction.

[0034] The transferable air volume is determined based on the remaining amount of air volume in the current branch that exceeds the minimum required air volume, after deducting the duration of low wind speed, residual dust load, and the impact of data reliability. ; in, Indicates the amount of air that can be transferred; Indicates the current branch air volume; This indicates the safety margin of the branch circuit as measured by air volume. This represents the equivalent air volume deduction value obtained by mapping low wind speed duration and residual dust load; This represents the equivalent air volume deduction value obtained by mapping low data reliability; First airflow deduction value It can be obtained by mapping the low wind speed duration and residual dust load to air volume through calibration coefficients, piecewise functions, or table lookups, and then adding them together; the second air volume deduction value. It can be obtained from the data's credibility level or insufficient credibility through calibration coefficients, piecewise functions, or table lookup mapping; , Both the safety margin Si and the branch air volume are expressed in the same unit. Used to form the base hold-up in the minimum required air volume. and Used to conservatively deduct the remaining amount of air volume that exceeds the minimum required air volume, the three are marked separately to avoid double counting of the same risk impact.

[0035] Only branches in a safe and transferable state are permitted to serve as sources of transferable airflow for closing redundant openings, reducing local branch airflow, or releasing fan frequency reduction.

[0036] Dust compatibility markings are determined by dust category, shared piping permits, explosion and flammability risks, pollution risks, and recycling strategies. For example, common non-combustible dust may be allowed to be shared within the same production line segment; dust from different product batches that pose a pollution risk may be restricted from being shared; combustible dust, recycled black powder, or metallic dust may require isolation, locking, or separate safety strategies.

[0037] Data credibility is used to characterize the credibility level of sensor, model and state data. For branches with insufficient data credibility, the branch deposition risk window table classifies them into restricted transfer state or isolated lock state to avoid automatic frequency reduction based on unreliable data.

[0038] Step 2: Divide the window status and reduce the frequency of the gated fan: Based on the branch deposition risk window table, the system classifies each dust-generating branch into at least one of the following window states: Safe and transferable state: The current branch airflow is higher than the minimum required airflow, the low air velocity is persistently low, the residual dust load is low, the dust compatibility marker allows for linkage, and the data reliability meets the requirements. In this state, the transferable airflow can be used for fine-tuning of the damper or reducing the fan frequency.

[0039] Limited Transfer Status: The current branch airflow is not below the minimum required airflow, but the persistent low airflow velocity, residual toner load, batch change status, or data reliability indicate that the branch should not continue to reduce airflow significantly. In this status, only minor limiting actions are allowed, and it is not permitted as the main source of frequency reduction margin.

[0040] Air replenishment required for repair: The current branch airflow is lower than the minimum required airflow or the capture capacity is insufficient. The system should prioritize opening the corresponding branch air valve, closing the redundant opening of branches without dust generation, checking the condition of hoses or hoods, or reducing system resistance by cleaning dust.

[0041] Purging required when a branch is in standby, batch change, cleaning, or a residual dust risk phase after a short production stoppage, or when the continuous low airflow exceeds the allowable threshold. The system should first perform purging or maintain the necessary airflow, and only allow frequency reduction after the continuous low airflow and residual dust load have decreased.

[0042] Isolated Lockdown Status: Dust type, product batch, explosion risk, pollution risk, or recycling strategy disallows this branch from participating in the same coordinated strategy. In this status, the branch does not participate in the shared dust removal revenue realization and is not used as a basis for wind turbine frequency reduction.

[0043] When any active dust-generating branch is in a state requiring supplemental air repair, purging, or isolation lockout, energy-saving actions that reduce the fan frequency are prohibited. Only dust-generating branches in a safe, transferable state can serve as a transferable airflow source for fan frequency reduction; dust-generating branches in a restricted transferable state are not considered a primary source of frequency reduction margin, but if their window boundaries meet and comply with minor limiting conditions, the system is not prevented from executing restricted fan frequency reduction. Through the above state classification, fan frequency reduction is no longer directly determined by the main static pressure or the number of equipment on / off states, but must first be gated through a branch deposition risk window table.

[0044] Step 3: Generate a record sheet for the realization of ash removal revenue and a phased collaborative control instruction sheet: like Figure 3 As shown, the dust removal revenue realization record table should at least record the dust layer incremental resistance of the candidate filter chamber, the expected dust removal reduction amount, the realizeable fan frequency reduction amount, and the expected fan power reduction amount.

[0045] Typical fields of this record table, Table 3:

[0046] As shown in Table 3, the dust removal benefit realization record table expands the filter chamber dust removal from a simple "resistance reduction" to a comprehensive judgment of "resistance reduction + energy saving realization"; dust removal is only considered to have been realized when the branch window allows it and the actual fan power reduction is within the expected power reduction range.

[0047] The statistical object of the dust removal fulfillment rate is the valid dust removal records that have been cleaned, have an expected fan power reduction greater than 0, and have complete data in the observation window. In one embodiment, records whose actual fan power reduction falls within the expected power reduction range are assigned a fulfillment value of 1, and records that do not fall within the expected power reduction range are assigned a fulfillment value of 0. The dust removal fulfillment rate is the weighted average of the fulfillment values ​​of all valid dust removal records. When it is necessary to reflect the degree of fulfillment, the single fulfillment value can be set as the ratio of the actual fan power reduction to the expected fan power reduction after being limited to 0 to 1.

[0048] The calculation method for the equivalent resistance of the filter chamber is as follows: ; in, Indicates the first The filter chamber is in the first Equivalent resistance for each control cycle; Indicates the pressure difference in the filter chamber; This indicates the amount of air passing through the filter chamber; This represents a dimensionless flow index that is greater than 0. This indicates the lower limit of positive air volume, and Using the same flow unit is to avoid calculation instability caused by low or zero flow. This formula is used to normalize the pressure difference according to the air volume in the filter chamber, forming an equivalent resistance index that can be compared under different air volume conditions.

[0049] The incremental resistance of the dust layer is: ; in, Indicates the resistance to the increase in dust layer; Indicates the baseline resistance of the clean filter media; The formula uses the max operation to limit the incremental resistance of the dust layer to a non-negative value, avoiding negative incremental resistance of the dust layer caused by measurement fluctuations or baseline updates, and serves as the basis for judging the value of dust removal.

[0050] The feasible fan frequency reduction for candidate filter chambers is determined as follows: Under the expected resistance conditions after cleaning the candidate filter chambers, the maximum fan frequency reduction that will not cause any active dust-generating branches to fall outside the branch deposition risk window is calculated: ; in, Indicates the first The achievable fan frequency reduction corresponding to each candidate filter chamber; Indicates the decrease in frequency of the candidate wind turbine; vertical line " It means "satisfied"; Indicates the first Each candidate filter chamber is in the expected resistance state after dust removal. And the frequency of the fan decreased At that time, the first The estimated air volume of each dust-generating branch; Indicates the first The expected resistance state of each candidate filter chamber after dust removal; Indicates the first Minimum required airflow for each dust-generating branch of an activity; Indicates "for any"; Indicates the current frequency of the wind turbine; This indicates the lowest frequency allowed by the current safety policy for the wind turbine; When using the equivalent resistance diameter, the expected resistance state after dust removal is as follows. The pressure drop can be determined based on the difference between the current equivalent resistance and the expected dust removal drop, or based on the sum of the baseline resistance of the cleaned filter media and the expected resistance of the residual dust layer. When using differential pressure, the expected differential pressure drop during dust removal is first converted into the equivalent resistance drop based on the air volume in the filter chamber. Expected branch air volume. Based on the fan characteristic curve, branch pipeline resistance, valve characteristics, and Perform pipeline network calculations, or determine the relationship based on historical calibrations for similar operating conditions, and correct the data through the observation window.

[0051] This formula is used to determine the maximum fan frequency reduction that will not cause any active branch to fall out of the branch deposition risk window under the expected resistance state after the candidate filter chamber is cleaned. It serves as the core quantitative basis for judging whether the cleaning can realize the fan frequency reduction.

[0052] The expected reduction in wind turbine power can be determined based on the achievable frequency reduction of the wind turbine, the current frequency of the wind turbine, the current power or current, the wind turbine characteristic curve, or the historical calibration relationship of similar operating conditions, and is provided to the second observation window for verification in the form of allowable deviation range.

[0053] When there is no fan frequency reduction that meets the conditions, or the maximum fan frequency reduction is lower than the frequency reduction release threshold, or the energy consumption of the compressed air is higher than the expected fan energy saving, the unnecessary dust removal action of the candidate filter chamber shall be suspended.

[0054] The conditions for realizing the benefits of dust removal include: the incremental resistance of the dust layer in the candidate filter chamber is higher than the dust removal candidate threshold; the expected dust removal fall-off amount is higher than the fall-off threshold; the compressed air pressure meets the pulse-jet requirements; the energy consumption of the pulse-jet compressed air is lower than the expected energy saving of the fan; the outlet dust pulse risk is lower than the risk threshold; and the expected realized fan frequency reduction after dust removal is not lower than the frequency reduction release threshold. Only when all of the above conditions are met simultaneously is the dust removal action considered to have revenue realization value.

[0055] Under the joint constraints of the branch deposition risk window table and the ash removal benefit realization record table, the system generates phased collaborative control instruction sheets. For example... Figure 4As shown, this instruction sheet includes at least branch repair actions, dust removal actions, and fan frequency release actions, along with their execution order. The instruction sheet also includes an observation window, prohibition conditions, rollback conditions, and reason codes.

[0056] Typical fields of this instruction form, Table 4:

[0057] A phased collaborative control instruction sheet must include at least three phases: The first stage is the branch window repair stage. If a branch is in a state that requires air replenishment or purging, the system will first perform air replenishment, valve opening, closing the redundant opening of the non-dust-generating branch, checking the status of the hose or hood, or performing a purging action.

[0058] The second stage is the candidate filter chamber cleaning stage. The system selects candidate filter chambers that meet the conditions from the cleaning revenue realization record table and performs staggered cleaning or postpones cleaning. Staggered cleaning can limit the number of filter chambers being cleaned at the same time, the pulse interval, and the pulse pressure, avoiding sudden changes in system static pressure and outlet dust pulses.

[0059] The third stage is the fan frequency reduction and release stage. After dust removal, the system verifies the filter chamber pressure differential drop, branch air volume changes, fan power changes, pulse jet air consumption, outlet dust, and safety interlock status through the second observation window.

[0060] Step 4: Phased Execution and Observation Window Verification: The system executes the branch repair and dust removal actions in the order of execution. Then, when the branch window boundary and safety interlock conditions are met, the system releases the fan frequency reduction according to the limit of the realizeable fan frequency reduction and enters the observation window for verification.

[0061] Specifically, the system first performs branch damper repair or purging actions. When any dust-generating branch is in a state requiring replenished air repair, the system opens the corresponding branch damper, closes redundant openings of non-dust-generating branches, checks the status of hoses or hoods, or reduces system resistance through dust removal. When any dust-generating branch is in a state requiring purging, the system performs purging or maintains the necessary airflow. The system collects branch airflow, branch pressure, damper opening, duration of low airflow, and residual dust load changes in the first observation window to verify whether the corresponding dust-generating branch has exited the state requiring replenished air repair or purging. If it has not exited, the system keeps the fan frequency locked and prohibits energy-saving actions that would reduce the airflow of that dust-generating branch.

[0062] Subsequently, the system performs dust removal on candidate filter chambers that meet the conditions for realizing dust removal benefits. The system collects data in the second observation window on the filter chamber pressure differential drop, branch airflow changes, fan power changes, pulse-jet air consumption, outlet dust changes, and safety interlock status.

[0063] Finally, the system performs fan frequency release and verification. When each active dust-generating branch still meets the boundaries in the branch deposition risk window table after dust removal, and the safety interlock does not trigger the prohibition condition, the system releases the fan frequency reduction according to the feasible fan frequency reduction limit, and continuously verifies the branch air volume and the actual fan power reduction; if the verification is successful, the frequency reduction is maintained; otherwise, the fan frequency is locked or rolled back, and the dust removal is marked as unfulfilled.

[0064] The second observation window is used to distinguish different cleaning results: If the filter chamber pressure differential decreases after dust removal and the actual fan power reduction falls within the expected power reduction range corresponding to the achievable fan frequency reduction, then the dust removal is recorded as achieved. If the filter chamber pressure differential decreases but the actual fan power reduction does not fall within the expected power reduction range, it is recorded as a failure to achieve the expected resistance reduction. If the filter chamber pressure differential decreases insufficiently, it is recorded as an ineffective dust removal. If the outlet dust level rises, it is recorded as a dust removal disturbance risk. The system updates the dust removal achievement rate based on the achieved records, the reason codes for non-achieved results, the actual fan power reduction, and the expected fan power reduction.

[0065] Step 5: Write-back Update and Security Degradation: The system writes back and updates the branch parameters and dust removal fulfillment rate based on the verification results, and switches to conservative control mode when the safety interlock is abnormal.

[0066] The write-back objects include branch airflow estimation coefficients, branch low airflow duration, residual dust load, filter chamber cleaning baseline resistance, dust layer incremental resistance, cleaning fulfillment rate, and non-fulfillment reason codes. Filter chambers with high cleaning fulfillment rates can improve their candidate ranking in subsequent similar operating conditions, while filter chambers with low cleaning fulfillment rates and repeated non-fulfillment reasons can have their cleaning temporarily suspended, their pulse jet intensity reduced, or maintenance prompts triggered.

[0067] like Figure 5 As shown, the safety boundary serves as a hard constraint before the instruction order is generated. The safety boundary can include the upper limit of outlet dust, the upper limit of ash hopper level, the availability status of the ash discharge device, the lower limit of compressed air pressure, the explosion-proof isolation status, the temperature or spark status, the maintenance door status, the emergency shutdown status, and the dust category compatibility status. When any of the following occurs: abnormal outlet dust, abnormal ash hopper discharge, insufficient compressed air pressure, abnormal explosion-proof isolation, abnormal temperature or spark, incompatible dust categories, or the branch data reliability falling below the reliability threshold, the system will stop or limit the corresponding energy-saving action and switch to conservative control mode.

[0068] Conservative control modes may include: stopping further reduction of fan frequency; maintaining or increasing airflow in key dust-generating branches; locking unnecessary dust removal; extending purging time; prompting manual inspection of branch hoses, air valves, filter chambers, or dust hoppers; restricting high-load production; switching to standby dust collectors; maintaining necessary ventilation and triggering alarms.

[0069] The above control method will be further explained through three specific application examples under typical operating conditions.

[0070] Example of sedimentation risk control in the feed and mixing section branch: A powder production line includes a feeding station, an unpacking station, a mixer, and a screening machine. The feeding station is in the process of feeding, the mixer is running, and the screening machine is in standby purging mode. The system collects data on pressure, valve opening, equipment status, and dust type for each branch, generating a branch deposition risk window table.

[0071] Among them, the minimum required air volume of the feeding branch is mainly determined by the air volume captured by the hood; the minimum required air volume of the mixing machine branch is determined by the negative pressure of the sealed cavity and the minimum conveying air velocity in the pipe; although the standby branch of the screening machine does not generate dust temporarily, it is classified as a state that needs to be purged because it has just finished running and the low air velocity is relatively high.

[0072] The system first performs standby branch purging on the screening machine and closes the redundant opening of all dust-free branches except for this standby purging branch. Within the first observation window, the low-velocity continuous flow rate of the screening machine branch decreases, the residual powder load decreases, and the window status changes from purging required to restricted transfer state. At this time, the system allows entry into the candidate filter chamber cleaning stage, but still restricts this branch from being the primary source of frequency reduction margin.

[0073] Example of energy saving performance evaluation after filter chamber cleaning: The dust layer in filter chamber B of a certain dust collector has a high incremental resistance. The dust removal benefit realization record table provides the expected dust removal reduction, the candidate realizeable fan frequency reduction, and the expected fan power reduction. When all active branches meet the window boundaries and no prohibition conditions are triggered, the system generates a phased collaborative control instruction sheet to perform staggered dust removal on filter chamber B.

[0074] Within the second observation window, the pressure difference in filter chamber B decreased significantly, the outlet dust did not increase abnormally, the compressed air consumption was within the allowable range, and each active branch still met the boundary of the branch deposition risk window table. The system released the fan frequency reduction according to the achievable fan frequency reduction limit; when the deviation between the actual fan power reduction and the expected fan power reduction was within the allowable range, the dust removal was recorded as achieved.

[0075] Under another operating condition, none of the active branches of filter chamber B triggered the prohibition conditions before cleaning. After filter chamber B completed cleaning, the system began to release the frequency reduction according to the candidate realizeable fan frequency reduction amount. The second observation window found that the air volume of a certain feeding branch fell out of the window boundary, and its low wind speed continued to increase while the residual powder load did not decrease. The system immediately stopped continuing to reduce the frequency and reversed the released frequency reduction amount, recording this cleaning as a failure to realize the resistance reduction due to the branch window limitation.

[0076] Example of frequency reduction due to dust compatibility limitations: A certain production line processes graphite dust and metal-containing powder at the same time. The two types of dust belong to pipelines or dust removal units that can be isolated from each other, and are coordinated by the same upper control system. The system marks the two types of branches as prohibited from linkage according to the dust category, product batch and recovery strategy; even if one type of branch has transferable air volume, the margin will not be used to realize the common benefit of the ash cleaning action corresponding to the other type of branch.

[0077] When the dust removal unit corresponding to the metal-containing powder branch has abnormal outlet dust, abnormal temperature or abnormal explosion-proof isolation, the system divides the branch into an isolated locked state, and switches the corresponding area to the conservative control mode.

[0078] As shown in Figure 1 , a second aspect of the present invention further provides a branch risk window and ash cleaning realization dust removal energy-saving control system, which includes a dust generation state acquisition module, a branch deposition risk window module, an ash cleaning benefit realization module, a phased instruction sheet generation module, a local execution module, a realization verification and back-writing module, and a safety degradation module.

[0079] The dust generation state acquisition module is configured to collect information of multiple dust generation branches, dust filter chambers, ash cleaning air supply, fans and safety interlocks.

[0080] The branch deposition risk window module is configured to generate and update the branch deposition risk window table of each dust generation branch, and output the window state and transferable air volume of each dust generation branch.

[0081] The ash cleaning benefit realization module is configured to generate an ash cleaning benefit realization record table, and determine the ash cleaning action, ash cleaning suspension action, realizable fan frequency reduction amount, estimated fan power reduction amount of the candidate filter chamber, and candidate sorting based on the ash cleaning realization rate.

[0082] The phased instruction sheet generation module is configured to generate a phased cooperative control instruction sheet including branch repair, purging, ash cleaning and fan frequency release actions based on the branch deposition risk window table and the ash cleaning benefit realization record table.

[0083] The local execution module is configured to issue the phased cooperative control instruction sheet to the frequency conversion fan, branch air valve, purging device and ash cleaning pulse valve group.

[0084] The realization verification and back-writing module is configured to verify the branch air volume, filter chamber pressure difference, fan power, injection air consumption, outlet dust and safety interlock state within the observation window, and back-write the branch air volume estimation coefficient, residual powder load, low wind speed duration, deviation between actual and estimated fan power reduction, and ash cleaning realization rate.

[0085] The safety degradation module is configured to switch to the conservative control mode when the safety interlock is abnormal.

[0086] The seven modules mentioned above work together to form a complete dust removal and energy-saving control chain: the dust generation status acquisition module collects operational data from each stage of the powder production line to form a dust generation status data set; the branch deposition risk window module generates a branch deposition risk window table based on this data, identifying the safety boundaries and allowable airflow for each dust-generating branch; the dust removal benefit realization module further generates a dust removal benefit realization record table, determining the realizeable fan frequency reduction and the expected fan power reduction; the phased instruction sheet generation module, under the joint constraints of the window table and the realization record table, generates a phased collaborative control instruction sheet including branch repair, purging, dust removal, and fan frequency reduction release actions; the local execution module sends the instruction sheet to the actuator; the realization verification and write-back module verifies the deviation between the actual and expected fan power reduction in the observation window and writes back the parameters; the safety degradation module, as the system's safety bottom line, switches to a conservative control mode in case of anomalies to ensure that energy-saving actions do not exceed the safety boundaries. These modules are sequentially connected to form a complete closed-loop control chain of "acquisition → identification → evaluation → execution → verification → correction".

[0087] This control system integrates branch-level risk control, dust removal energy saving, and safety interlock hard constraints into the same control chain, solving the problems of invisible branch risks, unrealized dust removal energy saving, disconnect between fan frequency reduction and dust removal action, and difficulty in integrating safety interlocks into the same control chain in existing dust removal systems. It achieves energy-saving and optimized operation of the dust removal system in the powder production line within the safety boundary.

[0088] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A branch risk window and dust removal energy-saving control method, characterized in that, Includes the following steps: Step 1: Collect operational information on multiple dust-generating branches, dust collector filter chambers, dust removal air supply, fans, and safety interlocks in the powder production line, and generate a branch deposition risk window table; The branch deposition risk window table shall at least record the minimum required air volume, current branch air volume, duration of low wind speed, residual dust load, dust compatibility mark, data reliability, and transferable air volume for the corresponding dust-generating branch. Step 2: According to the branch deposition risk window table, each dust-generating branch is divided into at least one of the following window states: safe transferable state, restricted transferable state, need for supplemental air repair state, need for purging state, and isolation and locking state. When any active dust-generating branch is in the need for supplemental air repair state, need for purging state, or isolation and locking state, energy-saving actions that reduce the frequency of the fan are prohibited. Step 3: Generate a dust removal benefit realization record table based on filter chamber operation information, dust removal air supply information, and fan operation information. Then, generate a phased collaborative control instruction sheet under the joint constraints of the branch deposition risk window table and the dust removal benefit realization record table. The dust removal benefit realization record table should at least record the dust layer increment resistance of the candidate filter chamber, the expected dust removal fall-off amount, the realizeable fan frequency reduction amount, and the expected fan power reduction amount. The phased collaborative control instruction sheet should at least include branch repair actions, dust removal actions, and fan frequency release actions, and their execution order. Step 4: Perform the branch repair and dust removal actions first, following the execution order. When the branch window boundary and safety interlock conditions are met, release the fan frequency reduction according to the available fan frequency reduction limit, and verify the branch air volume, filter chamber pressure difference, and actual fan power reduction in the corresponding observation window. If the verification is successful, maintain the frequency reduction; otherwise, lock or revert the fan frequency. Step 5: Write back and update the branch parameters and dust removal fulfillment rate based on the verification results, and switch to conservative control mode when the safety interlock is abnormal.

2. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step one, the minimum required air volume of the i-th dust-generating branch is determined by multiplying the maximum value among the air volume required for hood capture, the air volume corresponding to the minimum conveying air velocity in the pipeline, and the required air volume for purging by a margin coefficient, and then adding it to the maintenance air volume.

3. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step one, when no direct airflow timer is set in the dust-generating branch, the current branch airflow is estimated based on the branch pressure difference signal, branch damper opening, gas density, and branch calibration coefficient. The branch calibration coefficient is recursively corrected based on the measured wind speed, branch pressure change, damper opening change, and fan frequency change in the observation window.

4. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step one, the low wind speed duration is accumulated according to the control cycle when the current branch wind speed is lower than the minimum delivery wind speed, and decays or is cleared to zero after the branch wind speed recovers or a purging action is performed; the low wind speed duration is used to trigger the purging state and limit the fan frequency reduction action.

5. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step one, the low wind speed duration and residual dust load are jointly mapped to the first air volume deduction value, and the data reliability is mapped to the second air volume deduction value. The safety margin, the first air volume deduction value and the second air volume deduction value are deducted sequentially from the difference between the current branch air volume and the minimum required air volume to determine the transferable air volume. Only dust-generating branches that are in a safe and transferable state are allowed to participate in the fan frequency reduction.

6. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step two, the dust compatibility mark is determined by at least one of dust category, shared pipeline permission, explosion risk, pollution risk and recycling strategy; when the dust compatibility mark is prohibited from sharing or prohibited from linkage, the corresponding dust-generating branch is classified as isolated and locked, and does not participate in linkage frequency reduction or joint dust removal benefit realization.

7. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step three, the feasible fan frequency reduction amount for the candidate filter chamber is determined as follows: under the expected resistance state after the candidate filter chamber is cleaned, the maximum fan frequency reduction amount that will not cause any active dust-generating branch to fall out of the branch deposition risk window surface boundary is obtained; when there is no fan frequency reduction amount that meets the conditions, or the maximum fan frequency reduction amount is lower than the frequency reduction release threshold, or the energy consumption of the compressed air is higher than the expected fan energy saving, the unnecessary cleaning action of the candidate filter chamber is temporarily suspended.

8. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step three, the conditions for realizing the dust removal benefits include: the incremental resistance of the dust layer in the candidate filter chamber is higher than the dust removal candidate threshold, the expected dust removal fall amount is higher than the fall threshold, the compressed air pressure meets the injection requirements, the energy consumption of the injection compressed air is lower than the expected fan energy saving, the outlet dust pulse risk is lower than the risk threshold, and the expected fan frequency reduction amount that can be realized after dust removal is not lower than the frequency reduction release threshold.

9. The branch risk window and dust removal energy-saving control method according to claim 1, characterized in that, In step four, if the filter chamber pressure difference decreases after dust removal but the actual fan power decrease does not fall within the expected power decrease range corresponding to the realized fan frequency reduction, then the dust removal is recorded as resistance drop not realized. If the pressure difference in the filter chamber does not decrease sufficiently after dust removal, it is recorded as invalid dust removal; if the dust level at the outlet increases after dust removal, it is recorded as a risk of dust removal disturbance; and the dust removal fulfillment rate is updated based on the fulfilled records, the reason codes for non-fulfilled records, the actual decrease in fan power, and the expected decrease in fan power.

10. A branch risk window and dust removal energy-saving control system, characterized in that, include: The dust generation status acquisition module is used to collect information on multiple dust generation branches, dust collector filter chambers, dust removal air supply, fans, and safety interlocks. The branch deposition risk window module is used to generate and update the branch deposition risk window table for each dust-generating branch, and output the window status and allowable air volume for each dust-generating branch. The dust removal revenue realization module is used to generate a dust removal revenue realization record table and determine the dust removal action, dust removal suspension action, realizeable fan frequency reduction amount, expected fan power reduction amount, and candidate ranking based on the dust removal realization rate for candidate filter chambers. The phased instruction sheet generation module is used to generate phased collaborative control instruction sheets containing branch repair, purging, dust removal and fan frequency release actions based on the branch deposition risk window table and the dust removal revenue realization record table. The local execution module is used to send the phased collaborative control instruction sheet to the frequency converter fan, branch air valve, purging device and dust removal pulse valve group; The verification and write-back module is used to verify the branch air volume, filter chamber pressure difference, fan power, jetting air consumption, outlet dust and safety interlock status in the observation window, and write back the branch air volume estimation coefficient, residual powder load, low wind speed duration, deviation between actual and expected fan power reduction and dust removal fulfillment rate. The safety degradation module is used to switch to conservative control mode when the safety interlock fails.

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