A sewage filter control method based on time series analysis and pooling operation

Abstract

This invention provides a wastewater filter control method based on time-series analysis and pooling operation, comprising: reading filter operating parameters and scanning the status of on-site equipment to determine executable control processes; collecting filter process variables according to a sampling period and processing the collected values ​​to obtain effective time-series data; establishing a sliding time window based on the effective time-series data and calculating pooling characteristic values; executing constant water level filtration control based on the pooling characteristic values, and judging filtration stability, head blockage trend, turbidity time series, and backwashing requirements; confirming backwashing resources when the backwashing trigger conditions are met, executing flushing, primary filtration, and production restoration according to the backwashing sequence, and re-incorporating the restored filter into the closed-loop control. The beneficial effects of this invention are: by processing filter operating data through time-series analysis, pooling characteristic analysis, and closed-loop step sequence analysis, continuous linkage control of constant water level filtration, backwashing timing judgment, backwashing process control, and production restoration processes is achieved.

Description

Technical Field

[0001] This invention belongs to the field of wastewater treatment, and in particular relates to a wastewater filter control method based on time-series analysis and pooling operation. Background Technology

[0002] In actual wastewater treatment operations, the influent water quality, influent flow rate, and filter bed interception status of the filter bed typically exhibit continuous changes. Parameters such as liquid level, head blockage value, and turbidity do not change in isolation but rather form a trend-driven time-series process as filtration time increases. If the control system relies solely on single sample values ​​for judgment, it may easily misinterpret short-term disturbances as changes in actual operating conditions, or fail to respond in advance when a filter blockage trend has formed but has not yet reached a fixed threshold, thus affecting the judgment of backwashing timing.

[0003] Furthermore, most filter bed control systems process the collected data in a relatively simple way, typically only performing upper and lower limit alarms or fixed threshold comparisons, lacking a unified processing mechanism for abnormal range of collected values, single-cycle jumps, minor dead-zone fluctuations, and short-term data loss. When instruments experience momentary drift, brief communication interruptions, or valve feedback delays, the control system may directly use abnormal data in PID control or backwash judgment, leading to sudden changes in the output of the filtered water regulating valve, frequent alarms, or incorrect interruption of the automatic control process.

[0004] In constant water level filtration control, existing methods mostly use instantaneous liquid level as PID input. Liquid level measurement is greatly affected by water surface fluctuations, inlet and outlet water disturbances, and instrument noise, which can easily cause PID output oscillations, leading to frequent operation of the filtered water regulating valve. The regulating valve is in a high-frequency regulating state for a long time, which not only reduces the stability of liquid level control, but also increases the wear of the valve actuator, and makes it difficult for the regulating valve opening to accurately reflect the true filtration resistance of the filter bed.

[0005] Regarding backwash triggering, traditional control methods typically initiate backwashing based on a single condition such as maximum filtration time, fixed head blockage threshold, or excessive turbidity, lacking a comprehensive assessment of blockage growth trends, effluent water quality fluctuations, and regulating valve load status. When the filter clogging rate accelerates but the head blockage value has not yet reached the backwash setpoint, the system struggles to request backwash resources in a timely manner; conversely, when turbidity experiences a short-term peak but the overall water quality remains stable, unnecessary backwashing may occur.

[0006] In terms of backwashing execution, the stages of air washing, combined air-water flushing, water rinsing, exhaust, and primary filtration are all dependent on air volume, water volume, valve position status, liquid level, and water quality. Although the existing fixed-sequence control method can advance the process according to the set time, it is insufficient in identifying process anomalies such as insufficient backwash air volume, insufficient backwash water volume, unclear improvement trend of rinsing water quality, and large fluctuations in primary filtration turbidity. This can easily lead to insufficient rinsing or resumption of production before the primary filtration water quality has stabilized.

[0007] Therefore, a wastewater filter control scheme that combines data preprocessing, sliding time window, pooling feature extraction, trend prediction, comprehensive scoring, step sequence interlocking, and fault hold recovery is needed to improve the continuity and reliability of filter filtration control, backwash judgment, and backwash execution processes. Summary of the Invention

[0008] In view of this, the present invention aims to propose a wastewater filter control method based on time-series analysis and pooling operation, in order to solve at least one of the above-mentioned technical problems.

[0009] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0010] The first aspect of this invention proposes a wastewater filter control method based on time-series analysis and pooling operation, comprising:

[0011] Read the filter bed operating parameters and scan the status of on-site equipment; determine the executable control process based on login permissions, filter bed working mode and automatic control access conditions.

[0012] The PLC collects filter process variables according to the sampling period, and judges the range, change amplitude, dead zone and missing value of the collected value to obtain effective time series data.

[0013] A sliding time window is established based on the effective time series data, and pooling feature values ​​are calculated.

[0014] Based on the pooling characteristic values, constant water level filtration control is performed, and filtration stability, head blockage trend, turbidity time series and backwashing requirements are judged.

[0015] When the backwash triggering conditions are met, backwash resources are confirmed, and flushing, primary filtration, and production resumption are performed according to the backwash sequence. The restored filter is then reintegrated into the closed-loop control.

[0016] Furthermore, the system reads the filter's operating parameters and scans the status of on-site equipment. Based on login permissions, the filter's operating mode, and automatic control access conditions, it determines the executable control procedures, including:

[0017] After the PLC, host computer, communication module, online instruments and valve actuators are initialized, the PLC reads the operating control parameters, including filter operation parameters, valve control parameters, flushing sequence parameters, liquid level adjustment parameters and time sequence analysis parameters.

[0018] PLC scanning includes the status of field equipment, including field detection equipment, valve actuators, and backwashing actuators, and establishes a time-series data cache for process variables involved in the calculation;

[0019] Based on login permissions and the current operating mode of the filter, determine the permitted filtration control, level regulation, backwashing, forced rinsing, or manual test procedures.

[0020] Before entering the automatic control process, confirm that the filter is not disabled, the key valves are not seriously faulty, the liquid level has not reached the limit alarm, the backwash resources are not occupied, and the communication and instrument data are valid.

[0021] Furthermore, the PLC collects filter process variables according to the sampling period, and performs range, variation amplitude, dead zone, and missing value judgments on the collected values ​​to obtain valid time-series data, including:

[0022] The PLC collects filter process variables including liquid level, valve status, flow rate, head blockage value and water quality parameters, and writes the collected value of any variable at the current moment into the corresponding time-series data buffer.

[0023] Compare the current collected value with the corresponding instrument's allowable range. If the value exceeds the allowable range, mark it as an invalid value and prohibit it from participating in the pooling calculation for this cycle.

[0024] When the current acquired value is within the allowable range, compare the current acquired value with the previous valid value. If the difference exceeds the maximum allowable single-cycle change, it is marked as a jump anomaly. Based on the duration of the anomaly, maintain the previous valid value or generate an instrument anomaly status.

[0025] When the difference between the current collected value and the previous valid value is less than the set dead zone, the previous valid value is retained as the valid value for this period.

[0026] If the instrument fails to upload data for a short period of time, the previous valid value will be used to maintain the calculation. If the missing time exceeds the set allowable value, the corresponding variable will be prohibited from participating in critical automatic control.

[0027] Furthermore, establishing a sliding time window and calculating pooling feature values ​​based on the effective time-series data includes:

[0028] For any process variable involved in the calculation, the N most recent valid sampled values ​​are taken at the current moment to form a sliding time window;

[0029] When a new valid sample value enters the sliding time window, the earliest valid sample value is removed, so that the sliding time window remains at a fixed length.

[0030] Calculate the smoothing characteristics, trend characteristics, and fluctuation characteristics of liquid level based on the liquid level sliding time window;

[0031] Calculate the characteristics of blockage degree and blockage trend based on the sliding time window of the water head blockage value;

[0032] Water quality smoothness characteristics, peak water quality characteristics, trend water quality characteristics, and fluctuation water quality characteristics are calculated based on turbidity sliding time windows.

[0033] Based on the sliding time window of the execution volume and backwash process variables, the valve load characteristics, backwash air volume characteristics, and backwash water volume characteristics are calculated.

[0034] Furthermore, constant water level filtration control is performed based on the pooling characteristic values, including:

[0035] When the filter is in production filtration mode, read the level smoothing feature and the current effective level value, and calculate and control the level according to the set weight;

[0036] Calculate the liquid level deviation based on the set liquid level and the controlled liquid level;

[0037] When the absolute value of the liquid level deviation is less than the set liquid level dead zone, keep the current opening of the filtered water regulating valve unchanged;

[0038] When the absolute value of the liquid level deviation is not less than the set liquid level dead zone, the adjustment output is calculated based on the current liquid level deviation, historical liquid level deviation, sampling period and PID parameters.

[0039] The setpoint value of the filter water regulating valve is obtained by superimposing the regulating output with the basic opening degree, and the opening degree setpoint value is limited by the opening degree amplitude and the change amount between adjacent cycles.

[0040] The PLC converts the limited opening setpoint into an analog signal and outputs it to the filtered water regulating valve.

[0041] Further, assessments are made regarding filtration stability, head clogging trends, turbidity time series, and backwashing requirements, including:

[0042] The stability of filtration is determined by the difference between the controlled liquid level and the set liquid level, the characteristics of liquid level fluctuation, and the output change of the filtered water regulating valve in adjacent cycles.

[0043] When the control liquid level deviates from the set liquid level for a long period of time and the opening of the filtered water regulating valve is close to the opening limit, an abnormal filtration state is generated and sent to the backwash judgment process.

[0044] The blockage status is determined based on the blockage degree characteristics and blockage trend characteristics, and the remaining time to reach the blockage backwash set value is calculated when the blockage trend characteristics indicate that the head blockage value is rising.

[0045] The water quality status is determined based on water quality smoothness characteristics, water quality peak characteristics, water quality trend characteristics, and water quality fluctuation characteristics.

[0046] Scoring items are calculated based on cumulative filtration time, clogging degree characteristics, clogging trend characteristics, water quality smoothness characteristics, and valve load characteristics, and then weighted to obtain a comprehensive backwash score.

[0047] Furthermore, when the anti-washing trigger conditions are met, the anti-washing resources are confirmed, including:

[0048] A backwash request is generated when any one of the following conditions is met: cumulative filtration time, blockage degree characteristics, water quality smoothness characteristics, remaining time, or comprehensive backwash score;

[0049] When no backwash request is generated, maintain the production filtration status and continue to perform data acquisition, preprocessing, sliding time window update, pooling calculation and constant water level filtration control.

[0050] After generating a backwash request, determine whether backwash resources, including backwash water supply equipment, backwash gas supply equipment, backwash pipelines, drainage and public facilities, are available.

[0051] When backwashing resources are available, lock the current filter backwashing process and prevent other filters from occupying the locked resources;

[0052] When the anti-washing resource is unavailable, it enters the anti-washing waiting state and accumulates the waiting time. When the waiting time reaches the maximum waiting time, an anti-washing waiting timeout state is generated.

[0053] Furthermore, rinsing is performed according to the backwash sequence, including:

[0054] After the backwash resources are locked, the filter-related valves are switched to the backwash preparation state in sequence, and the corresponding valves are waited for feedback on their position.

[0055] If any valve fails to receive feedback on the target arrival within the set valve action time, a valve action timeout state is generated and a flushing fault state is entered.

[0056] When the relevant filtration valves are in place and the liquid level is within the allowable range, the air washing stage begins.

[0057] During the air washing stage, the backwash air supply path is opened and the backwash air supply equipment is started. The backwash air volume is collected and the backwash air volume characteristics are calculated. When the backwash air volume characteristics do not meet the air washing requirements and continue to exceed the alarm delay, the flushing fault state is entered.

[0058] After the air washing time reaches the set air washing time, the backwash water supply path is opened and the backwash water supply equipment is started to enter the air-water combined flushing stage;

[0059] After the combined air-water flushing time reaches the set time, the backwash air supply path is closed, the backwash air supply equipment is stopped, and the water rinsing stage begins. After the water rinsing time reaches the set time, the exhaust stage begins.

[0060] Furthermore, the initial filtration and production resumption are performed according to the backwashing sequence, and the restored filter is reintegrated into the closed-loop control, including:

[0061] During the exhaust phase, the exhaust valve is opened and the exhaust time is accumulated. After the exhaust time reaches the set exhaust time, the exhaust valve is closed and feedback on whether it is closed is received.

[0062] If the exhaust valve fails to close completely within the set time, an exhaust valve malfunction status is generated and the flushing malfunction status is entered.

[0063] After the vent valve is closed, the control valve for the inlet water and the valves related to the primary filter discharge will enter the primary filtration stage;

[0064] Collect water quality parameters of the primary filtered water and calculate the smoothness characteristics and fluctuation characteristics of the primary filtered water.

[0065] When the initial filtration water quality smoothness characteristics, initial filtration water quality fluctuation characteristics, and initial filtration duration meet the initial filtration qualification conditions, the production resumption stage begins.

[0066] If the initial filtration duration reaches the maximum allowable time and still fails to meet the requirements, an initial filtration failure status is generated and the system enters maintenance or waiting for manual confirmation status.

[0067] When production resumes, close the valves related to the primary filter discharge, open the filtered water regulating valve, reset the cumulative filtration time to zero, use the current blockage characteristics as the new head blockage benchmark, and re-execute closed-loop control.

[0068] A second aspect of this invention proposes a wastewater filter control system based on time-series analysis and pooling operation, characterized in that it includes:

[0069] The host computer is used to receive login information, display the filter tank's operating status and alarm status, and send operating parameters to the PLC;

[0070] Online instruments are used to collect filter process variables and backwashing process variables, and send the collected data to the PLC through a communication module.

[0071] The PLC is used to execute the method described in the first aspect, including judging the validity of the collected data, forming valid time-series data, establishing a sliding time window, calculating pooling characteristic values, executing constant water level filtration control, judging backwashing requirements and controlling the backwashing sequence.

[0072] The valve actuator is used to drive the valves related to filtration, backwashing, venting and primary filtration discharge according to the valve commands output by the PLC, and to feed back the valve position status to the PLC.

[0073] Compared with the prior art, the present invention has the following beneficial effects:

[0074] 1. By establishing a time-series data buffer for process variables after system startup, and continuously collecting variables such as liquid level, flow rate, head blockage value, turbidity, valve opening, and backwashing process during filter operation, the filter control process is transformed from single-point sampling control to continuous analysis control based on time-series data.

[0075] 2. Before the collected values ​​enter the control calculation, range judgment, change range judgment, dead zone handling, and missing data handling are performed. This can prevent out-of-range data, jump data, and long-term missing data from directly participating in key automatic control, and use the previous valid value to maintain the calculation when short-term data is missing, thereby improving the consistency of control input data.

[0076] 3. The stability of filtration is judged by controlling the liquid level deviation, liquid level fluctuation value and the output change of the filtered water regulating valve. When the controlled liquid level deviates from the set liquid level for a long time and the opening of the regulating valve is close to the limit, an abnormal filtration state is generated, so as to establish a correlation between the liquid level control state and the filtration capacity of the filter.

[0077] 4. By using the average turbidity pooling value, the maximum turbidity pooling value, the turbidity trend slope, and the turbidity fluctuation value, the water quality status can be determined. It can distinguish between overall water quality exceeding limits, short-term peak risk, continuous turbidity increase, and abnormal water quality fluctuation, so that water quality judgment no longer depends solely on the instantaneous turbidity value.

[0078] 5. In the air washing stage, the minimum pooling value of backwash air volume is used to determine insufficient air volume. In the combined air and water washing stage, the average pooling value of backwash air volume and the average pooling value of backwash water volume are used to determine the washing quality. In the water rinsing stage, the average turbidity value and the turbidity trend slope are used to determine the rinsing status. In the primary filtration stage, the average turbidity value and the primary filtration turbidity fluctuation value are used to determine the primary filtration qualification status, so that the backwashing process has continuous status identification capability.

[0079] 6. After backwashing is completed, the cumulative filtration time is reset to zero. The current average head blockage pooling value is used as the new head blockage benchmark. The blockage growth value is calculated based on the subsequent average head blockage pooling value and this benchmark, so that the filtration cycle benchmark can be re-established each time the filter resumes production. Attached Figure Description

[0080] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0081] Figure 1 This is a schematic diagram of the workflow of a wastewater filter control method based on time-series analysis and pooling operation as described in an embodiment of the present invention. Detailed Implementation

[0082] It should be noted that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application. In the absence of conflict, the embodiments and features in the embodiments of this invention can be combined with each other. In order to make the purpose, technical solution and advantages of this application clearer, the following describes this application in further detail with reference to the accompanying drawings and embodiments.

[0083] like Figure 1 As shown, a wastewater filter control method based on time-series analysis and pooling operation includes:

[0084] S1. Read the filter bed operating parameters and scan the status of on-site equipment. Determine the executable control process based on login permissions, filter bed working mode and automatic control access conditions.

[0085] S2 and PLC collect filter process variables according to the sampling period, and judge the range, change amplitude, dead zone and missing value of the collected value to obtain effective time series data;

[0086] S3. Establish a sliding time window based on the effective time series data and calculate the pooling feature value;

[0087] S4. Perform constant water level filtration control based on the pooling characteristic value, and judge the filtration stability, head blockage trend, turbidity time sequence and backwashing requirements.

[0088] S5. When the backwash triggering condition is met, confirm the backwash resources, perform flushing, primary filtration and production recovery according to the backwash sequence, and reintegrate the recovered filter into the closed-loop control.

[0089] Read the filter's operating parameters and scan the status of on-site equipment. Based on login permissions, filter operating mode, and automatic control access conditions, determine the executable control procedures, including:

[0090] After the PLC, host computer, communication module, online instruments and valve actuators are initialized, the PLC reads the operating control parameters, including filter operation parameters, valve control parameters, flushing sequence parameters, liquid level adjustment parameters and time sequence analysis parameters.

[0091] PLC scanning includes the status of field equipment, including field detection equipment, valve actuators, and backwashing actuators, and establishes a time-series data cache for process variables involved in the calculation;

[0092] Based on login permissions and the current operating mode of the filter, determine the permitted filtration control, level regulation, backwashing, forced rinsing, or manual test procedures.

[0093] Before entering the automatic control process, confirm that the filter is not disabled, the key valves are not seriously faulty, the liquid level has not reached the limit alarm, the backwash resources are not occupied, and the communication and instrument data are valid.

[0094] In some embodiments, after the system is powered on, the PLC, host computer, communication module, online instruments, and valve actuators complete initialization sequentially. After initialization, the PLC reads the operating control parameters, which include filter operation parameters, valve control parameters, flushing sequence parameters, liquid level adjustment parameters, and time-series analysis parameters.

[0095] The PLC then scans the status of the field equipment. The field equipment includes field monitoring equipment, valve actuators, and backwash actuators. The field monitoring equipment collects filter operation data, the valve actuators perform valve actions related to filtration, backwashing, venting, and primary filter discharge, and the backwash actuators provide backwash water and backwash air.

[0096] The system establishes a time-series data cache for the process variables involved in the calculation. These process variables include filter filtration process variables and backwashing process variables. During the initialization phase, the system clears invalid historical data and sets the filter status to one of the following: standby, production, maintenance, testing, or disabled.

[0097] After the host computer enters the login interface, the operator enters their account and password. After successful login, the system grants corresponding operation functions according to login permissions and displays the filter's operating status, valve status, process variable status, and alarm status on the main control screen.

[0098] The system determines the permissible control flow based on the current operating mode of the filter:

[0099] When the filter is in production mode, the system allows filtration control, level regulation, and backwashing processes. The PLC opens the inlet valve and the filtered water regulating valve according to process conditions to enter constant water level filtration control. When the filter is in maintenance mode, the system prohibits normal filtration and allows operators to forcibly start the backwashing process. When the filter is in test mode, the system prohibits filtration and backwashing processes and only allows manual testing of the on-site equipment. When the filter is in disabled mode, the system prohibits automatic and manual operation, keeping the filter in a stopped state.

[0100] Before entering the automatic control process, the system performs an automatic control access judgment. Access conditions include: the filter is not in a disabled state, critical valves are not seriously faulty, the liquid level has not reached the limit alarm, backwash resources are not occupied, and communication and instrument data are valid. Once these conditions are met, the system proceeds to the subsequent data acquisition and closed-loop control process.

[0101] The PLC collects filter process variables according to the sampling period, and performs range, variation amplitude, dead zone, and missing value judgments on the collected values ​​to obtain valid time series data, including:

[0102] The PLC collects filter process variables including liquid level, valve status, flow rate, head blockage value and water quality parameters, and writes the collected value of any variable at the current moment into the corresponding time-series data buffer.

[0103] Compare the current collected value with the corresponding instrument's allowable range. If the value exceeds the allowable range, mark it as an invalid value and prohibit it from participating in the pooling calculation for this cycle.

[0104] When the current acquired value is within the allowable range, compare the current acquired value with the previous valid value. If the difference exceeds the maximum allowable single-cycle change, it is marked as a jump anomaly. Based on the duration of the anomaly, maintain the previous valid value or generate an instrument anomaly status.

[0105] When the difference between the current collected value and the previous valid value is less than the set dead zone, the previous valid value is retained as the valid value for this period.

[0106] If the instrument fails to upload data for a short period of time, the previous valid value is used to maintain the calculation. If the missing time exceeds the set allowable value, the corresponding variable is prohibited from participating in critical automatic control.

[0107] In some embodiments, after the filter begins operation, the PLC collects process variables of the filter according to a set sampling period. Liquid level, valve feedback, and regulating valve opening can use shorter sampling periods, while flow rate, turbidity, and head blockage value can use longer sampling periods. The collected value of any variable at the current moment is denoted as... t is the sampling time.

[0108] For liquid level data, the system generates a liquid level sequence: ;

[0109] For head blockage value data, the system generates a blockage sequence: ;

[0110] For turbidity data, the system generates a turbidity sequence: ;

[0111] For the control valve opening data, the system generates an opening sequence: ;

[0112] After obtaining the current collected value, the system does not use it directly for control, but first performs a validity check.

[0113] First, determine the measurement range. Taking liquid level as an example, when the liquid level gauge's range is... to At that time, the current liquid level value satisfies: ;

[0114] If the current liquid level value is valid, then it is valid; otherwise, the current liquid level value is deemed invalid and prohibited from participating in the pooling calculation for this cycle. Other process variables are judged in the same way according to the allowable range of the corresponding instrument.

[0115] The system then judges the magnitude of the change. It compares the current collected value with the previous valid value, and if the following conditions are met:

[0116] ;

[0117] When this happens, the system marks the current collected value as an anomaly. This represents the maximum allowable single-cycle change for the corresponding variable. For abrupt outliers, the system decides whether to use the previous valid value for calculation or generate an instrument anomaly status based on the duration of the anomaly.

[0118] Then dead zone processing is performed. This occurs when the difference between the current measured value and the previous valid value satisfies:

[0119] ;

[0120] When this happens, the system considers the variable to have not changed effectively and retains the previous valid value as the valid value for the current period. Here, vacuumisilon is the set dead zone for the corresponding variable.

[0121] If a certain instrument fails to upload data for a short period of time, the system uses the previous valid value to maintain the calculation; if the missing time exceeds the set allowable value, the system determines that the instrument is faulty and prohibits the corresponding variable of the instrument from continuing to participate in critical automatic control.

[0122] Through the above preprocessing, the system obtains valid time series data and sends the valid time series data into the sliding time window.

[0123] Based on the effective time-series data, a sliding time window is established and pooling feature values ​​are calculated, including:

[0124] For any process variable involved in the calculation, the N most recent valid sampled values ​​are taken at the current moment to form a sliding time window;

[0125] When a new valid sample value enters the sliding time window, the earliest valid sample value is removed, so that the sliding time window remains at a fixed length.

[0126] Calculate the smoothing characteristics, trend characteristics, and fluctuation characteristics of liquid level based on the liquid level sliding time window;

[0127] Calculate the characteristics of blockage degree and blockage trend based on the sliding time window of the water head blockage value;

[0128] Water quality smoothness characteristics, peak water quality characteristics, trend water quality characteristics, and fluctuation water quality characteristics are calculated based on turbidity sliding time windows.

[0129] Based on the sliding time window of the execution volume and backwash process variables, the valve load characteristics, backwash air volume characteristics, and backwash water volume characteristics are calculated.

[0130] In some embodiments, preprocessed valid data enters a sliding time window. For any process variable x involved in the calculation, the system takes the n most recent valid sampled values ​​at the current time t to form a sliding time window:

[0131] ;

[0132] When a new valid sample value enters the sliding time window, the system removes the earliest valid sample value from the window, thus maintaining the sliding time window at a fixed length.

[0133] The system calculates pooling eigenvalues ​​based on a sliding time window.

[0134] Average pooling value: ;

[0135] For the liquid level, the average pooling value of the liquid level is obtained: ;

[0136] For the head blockage value, the average pooling value of the blockage is obtained: ;

[0137] For turbidity, the average pooling value of turbidity is obtained: ;

[0138] The trend slope is calculated using a linear fitting method, fitting the data within the window as follows: ;

[0139] Where 'a' is the trend slope. When When, it indicates that the variable is on an upward trend; when When the value is 0, it indicates that the variable is showing a downward trend.

[0140] The degree of window fluctuation is: ;

[0141] The system calculates the smoothness characteristics, trend characteristics, and fluctuation characteristics of liquid level based on the sliding time window of liquid level; calculates the degree of blockage and trend characteristics based on the sliding time window of head blockage value; calculates the smoothness characteristics, peak characteristics, trend characteristics, and fluctuation characteristics of water quality based on the sliding time window of turbidity; and calculates the valve load characteristics, backwash air volume characteristics, and backwash water volume characteristics based on the sliding time window of execution quantity and backwash process variables.

[0142] Performing constant water level filtration control based on the pooling characteristic values ​​includes:

[0143] When the filter is in production filtration mode, read the level smoothing feature and the current effective level value, and calculate and control the level according to the set weight;

[0144] Calculate the liquid level deviation based on the set liquid level and the controlled liquid level;

[0145] When the absolute value of the liquid level deviation is less than the set liquid level dead zone, keep the current opening of the filtered water regulating valve unchanged;

[0146] When the absolute value of the liquid level deviation is not less than the set liquid level dead zone, the adjustment output is calculated based on the current liquid level deviation, historical liquid level deviation, sampling period and PID parameters.

[0147] The setpoint value of the filter water regulating valve is obtained by superimposing the regulating output with the basic opening degree, and the opening degree setpoint value is limited by the opening degree amplitude and the change amount between adjacent cycles.

[0148] The PLC converts the limited opening setpoint into an analog signal and outputs it to the filtered water regulating valve.

[0149] In some embodiments, when the filter is in production filtration mode, the system does not directly use the instantaneous liquid level for PID control, but instead integrates the average pooled liquid level value, the median pooled liquid level value, and the current effective liquid level value into the control liquid level: ;

[0150] in: ;

[0151] The control liquid level is used for control purposes. This represents the average pooling value based on liquid level. This represents the median pooling value of the liquid level. This is the current effective liquid level value. To set weights.

[0152] The system is set with liquid level To calculate the liquid level deviation, use the target as an example: ;

[0153] When the absolute value of the liquid level deviation is less than the set liquid level dead zone hour: ;

[0154] The system maintains the current opening degree of the filtered water regulating valve unchanged.

[0155] When the absolute value of the liquid level deviation is not less than the set liquid level dead zone, the system starts discrete PID calculation:

[0156] ;

[0157] in, This is the current PID output. This is the proportionality coefficient. The integral coefficient is... The differential coefficients are... This represents the current cycle deviation. This represents the deviation from the previous cycle.

[0158] The set value for the opening of the filtered water regulating valve is: ;

[0159] in, Based on the basic opening.

[0160] The system limits the given opening value: ;

[0161] in, For the minimum allowable opening, This represents the maximum permissible opening.

[0162] The system further limits the output variation between adjacent periods: ;

[0163] in, This represents the maximum permissible change between adjacent periods.

[0164] Ultimately, the PLC will limit the... The signal is converted into an analog signal and output to the filtered water regulating valve. The feedback opening degree of the filtered water regulating valve is written into the corresponding timing data buffer for subsequent valve load judgment.

[0165] Determine filtration stability, head clogging trend, turbidity time series, and backwashing requirements, including:

[0166] The stability of filtration is determined by the difference between the controlled liquid level and the set liquid level, the characteristics of liquid level fluctuation, and the output change of the filtered water regulating valve in adjacent cycles.

[0167] When the control liquid level deviates from the set liquid level for a long period of time and the opening of the filtered water regulating valve is close to the opening limit, an abnormal filtration state is generated and sent to the backwash judgment process.

[0168] The blockage status is determined based on the blockage degree characteristics and blockage trend characteristics, and the remaining time to reach the blockage backwash set value is calculated when the blockage trend characteristics indicate that the head blockage value is rising.

[0169] The quality status of the effluent is determined based on the smoothness characteristics, peak characteristics, trend characteristics, and fluctuation characteristics of the water quality.

[0170] Scoring items are calculated based on cumulative filtration time, clogging degree characteristics, clogging trend characteristics, water quality smoothness characteristics, and valve load characteristics, and then weighted to obtain a comprehensive backwash score.

[0171] In some embodiments, during the filtration process, the system continuously determines whether the filter bed is in a stable filtration state.

[0172] Liquid level stability is determined by the following conditions: ;

[0173] and: ;

[0174] in, This represents the liquid level fluctuation value. Set the value for liquid level fluctuation.

[0175] The stability of a control valve is judged by changes in its opening degree: ;

[0176] When the liquid level pooling value is close to the set liquid level, the liquid level fluctuation value is lower than the set value, the rate of change of the regulating valve opening is small, the average turbidity of the effluent does not exceed the set value, and the head blockage value does not reach the backwash condition, the system determines that the filter is in normal filtration state. If the controlled liquid level deviates from the set liquid level for a long period of time, and the opening of the filtered water regulating valve is close to the opening limit, the system generates a filtration abnormality state and sends this state to the backwash judgment process.

[0177] The system continuously analyzes the head blockage value during the filtration process. The average pooling value for head blockage is:

[0178] ;

[0179] The slope of the head blockage trend is: ;

[0180] when: ;

[0181] This indicates that the filter bed is becoming increasingly clogged. If: ;

[0182] The system then determines that the filter bed has a rapid clogging trend, among which, Set a value for blocking the trend.

[0183] If the current average pooling value of head blockage has not yet reached the blockage backwash setpoint, but the slope of the head blockage trend is greater than zero, the system calculates the remaining time to reach the blockage backwash setpoint: ;

[0184] in, This is the setting for blocking backwashing. If: ;

[0185] The system then determines that the filter is about to reach the backwashing condition and prepares to apply for backwashing resources. Time to prepare for backwashing.

[0186] The system performs time-series analysis on the effluent turbidity. The average turbidity pooling value is: ;

[0187] The maximum pooling value for turbidity is: ;

[0188] Turbidity fluctuation value: ;

[0189] when: ;

[0190] If the alarm delay continues for an extended period, the system determines that the water quality is abnormal. If: ;

[0191] The system generates a water quality risk alarm. If: ;

[0192] The system considers that the filter layer may be at risk of penetration and incorporates this risk into the backwashing decision.

[0193] The system periodically calculates the backwashing requirement score. The filtration time score is: ;

[0194] in, This represents the current cumulative filtering time. This is the maximum filtering time. When... When the time is equal to 1, it is calculated as 1.

[0195] The level of congestion is rated as follows: ;

[0196] when When the time is equal to 1, it is calculated as 1.

[0197] The blocking trend score is: ;

[0198] when When the time is equal to 1, it is calculated as 1.

[0199] The effluent water quality score is: ;

[0200] when When the time is equal to 1, it is calculated as 1.

[0201] The load rating of the control valve is: ;

[0202] in, The average value of the valve opening. This is the value for determining high opening degree. When... When the time is right, it can be calculated as 1.

[0203] The overall anti-washing score is: ;

[0204] in, Let each term have a weight, and satisfy the following conditions: .

[0205] When the anti-washing trigger conditions are met, confirm the anti-washing resources, including:

[0206] A backwash request is generated when any one of the following conditions is met: cumulative filtration time, blockage degree characteristics, water quality smoothness characteristics, remaining time, or comprehensive backwash score;

[0207] When no backwash request is generated, maintain the production filtration status and continue to perform data acquisition, preprocessing, sliding time window update, pooling calculation and constant water level filtration control.

[0208] After generating a backwash request, determine whether backwash resources, including backwash water supply equipment, backwash gas supply equipment, backwash pipelines, drainage and public facilities, are available.

[0209] When backwashing resources are available, lock the current filter backwashing process and prevent other filters from occupying the locked resources;

[0210] When the anti-washing resource is unavailable, it enters the anti-washing waiting state and accumulates the waiting time. When the waiting time reaches the maximum waiting time, an anti-washing waiting timeout state is generated.

[0211] In some embodiments, the system determines whether to initiate anti-washing based on a hard threshold, trend prediction, and a comprehensive score.

[0212] When the cumulative filtration time reaches the maximum filtration time: ;

[0213] The system triggered a reverse scrubbing request.

[0214] When the average pooling value of head blockage reaches the blockage backwash set value: ;

[0215] The system triggered a reverse scrubbing request.

[0216] When the average turbidity value of the effluent reaches the set turbidity value and continues to exceed the set delay: The system triggered a reverse shuffling request.

[0217] When the remaining time for blocking trend prediction is less than the reshuffling preparation time: ;

[0218] The system triggered a backwashing preparation request ahead of schedule.

[0219] When the overall back-washing score reaches the back-washing threshold: ;

[0220] The system triggers an intelligent backwashing request, in which, This is the threshold for backwashing scoring.

[0221] If none of the above conditions are met, the filter will continue to operate in production filtration mode and will continue to perform data acquisition, preprocessing, sliding time window updates, pooling calculations, and constant water level filtration control.

[0222] Upon generating a backwash request or backwash preparation request, the system determines whether backwash resources are available. Backwash resources include backwash water supply equipment, backwash air supply equipment, backwash pipelines, drainage systems, and common equipment. If backwash resources are available, the system locks the backwash process for the current filter to prevent other filters from simultaneously occupying the same resources. If backwash resources are temporarily unavailable, the system enters a backwash waiting state and accumulates the waiting time.

[0223] When the waiting time is satisfied: When this happens, the system triggers a backwash waiting timeout state and, according to the control strategy, continues filtering, enters maintenance, or waits for manual processing.

[0224] Perform rinsing according to the backwash sequence, including:

[0225] After the backwash resources are locked, the filter-related valves are switched to the backwash preparation state in sequence, and the corresponding valves are waited for feedback on their position.

[0226] If any valve fails to receive feedback on the target arrival within the set valve action time, a valve action timeout state is generated and a flushing fault state is entered.

[0227] When the relevant filtration valves are in place and the liquid level is within the allowable range, the air washing stage begins.

[0228] During the air washing stage, the backwash air supply path is opened and the backwash air supply equipment is started. The backwash air volume is collected and the backwash air volume characteristics are calculated. When the backwash air volume characteristics do not meet the air washing requirements and continue to exceed the alarm delay, the flushing fault state is entered.

[0229] After the air washing time reaches the set air washing time, the backwash water supply path is opened and the backwash water supply equipment is started to enter the air-water combined flushing stage;

[0230] After the combined air-water flushing time reaches the set time, the backwash air supply path is closed, the backwash air supply equipment is stopped, and the water rinsing stage begins. After the water rinsing time reaches the set time, the exhaust stage begins.

[0231] In some embodiments, after the backwash resource is confirmed and locked by the current filter, the filter enters the backwash preparation stage. The system first closes the inlet valve to stop the filter from continuing to receive water; then it closes the after-filtration water regulating valve to stop the filter from discharging water to subsequent processes; then it opens the drain valve to allow the filter to enter a flushable state.

[0232] After each valve action, the PLC waits for feedback on the valve's position. If no feedback is received within a set time after issuing an open valve command, the valve opening is considered a fault; if no feedback is received within a set time after issuing a close valve command, the valve closing is considered a fault. Valve action timeout is determined as follows: ;

[0233] When this condition is met and the target feedback is not received, the system enters a flushing failure state.

[0234] During the backwash preparation phase, the system also checks if the liquid level is within the allowable range. If the liquid level is too high, the system continues to drain or is prohibited from proceeding to the next step; if the liquid level is too low and may cause the equipment to run dry, the system is prohibited from starting the backwash water pump. Once the inlet valve is fully closed, the filtered water valve is fully closed, the drain valve is fully open, and the liquid level meets the requirements, the system enters the air washing phase.

[0235] After air washing begins, the system opens the backwash inlet valve and starts the backwash fan. During air washing, the system continuously collects backwash airflow and establishes a backwash airflow timing window. The system calculates the minimum pooling value of the airflow:

[0236] ;

[0237] in, This represents the current backwash air volume. If: ;

[0238] If the airflow continues beyond the alarm delay, the system determines that the air washing volume is insufficient and triggers an abnormal washing alarm. The system also accumulates the air washing time, and when the following conditions are met: ;

[0239] At this point, the air washing stage ends, and the system enters the combined air-water flushing stage.

[0240] After the combined air-water flushing begins, the system keeps the backwash air inlet valve open and simultaneously opens the backwash water inlet valve, starting the backwash water pump. The system performs pooling calculations on the backwash airflow and backwash water flow separately. The average backwash airflow is:

[0241] ;

[0242] The average backwash water volume is: ;

[0243] in, This is the sampled value of the backwash water volume. If: ;or: ;

[0244] If the alarm delay continues for an extended period, the system determines that the combined air-water flushing is of insufficient quality.

[0245] The system's cumulative air-water combined flushing time, when it meets the following conditions: At this point, the system ends the combined air-water flushing and enters the water rinsing stage.

[0246] After the water rinsing stage begins, the system closes the backwash air inlet valve, stops the backwash fan, keeps the backwash water valve open, and continues to use water flow for rinsing. During the rinsing process, the system continuously collects the turbidity of the effluent or relevant water quality parameters, and calculates the average turbidity and trend of the rinsing turbidity.

[0247] like: This indicates that the quality of the rinsing water is improving.

[0248] like: This indicates that the rinsing process is nearing completion. If the rinsing time reaches the set value:

[0249] ;

[0250] The system enters the venting phase. If insufficient water, abnormal liquid level, or abnormal valve status occurs during rinsing, the system enters a flushing failure state.

[0251] Perform initial filtration and production recovery according to the backwashing sequence, and reintegrate the recovered filter into the closed-loop control system, including:

[0252] During the exhaust phase, the exhaust valve is opened and the exhaust time is accumulated. After the exhaust time reaches the set exhaust time, the exhaust valve is closed and feedback is waited for when it is fully closed.

[0253] If the exhaust valve fails to close completely within the set time, an exhaust valve malfunction status is generated and the flushing malfunction status is entered.

[0254] After the vent valve is closed, the control valve for the inlet water and the valves related to the primary filter discharge will enter the primary filtration stage;

[0255] Collect water quality parameters of the primary filtered water and calculate the smoothness characteristics and fluctuation characteristics of the primary filtered water.

[0256] When the initial filtration water quality smoothness characteristics, initial filtration water quality fluctuation characteristics, and initial filtration duration meet the initial filtration qualification conditions, the production resumption stage begins.

[0257] If the initial filtration duration reaches the maximum allowable time and still fails to meet the requirements, an initial filtration failure status is generated and the system enters maintenance or waiting for manual confirmation status.

[0258] When production resumes, close the valves related to the primary filter discharge, open the filtered water regulating valve, reset the cumulative filtration time to zero, use the current blockage characteristics as the new head blockage benchmark, and re-execute closed-loop control.

[0259] In some embodiments, after water rinsing is completed, the system enters the venting phase. Once the venting phase begins, the system opens the vent valve to expel residual air from the filter and pipelines. The system accumulates the venting time.

[0260] When satisfied When the system closes the exhaust valve, it waits for the exhaust valve to close completely. If the exhaust valve fails to close completely within the set time, the system determines that the exhaust valve is faulty and enters the flushing fault state; if the exhaust valve closes normally, the system enters the initial filtration stage.

[0261] After the primary filtration begins, the system reopens the inlet valve to allow water to flow back into the filter bed. However, the filtered water does not directly enter subsequent treatment processes; instead, it is discharged through the primary filtration discharge or return path. The system opens the corresponding discharge valve or flushing water valve to discharge the primary filtration water to the designated location.

[0262] The system continuously collects the turbidity of the effluent during the initial filtration stage and calculates the average and fluctuation values ​​of the initial filtration turbidity. , ;

[0263] The initial average turbidity was below the acceptable value: ;

[0264] Furthermore, the turbidity fluctuation is below the stability threshold: ;

[0265] The system determines that the initial filtration is qualified. If the initial filtration is qualified after reaching the minimum set time, the system enters the production resumption phase. If the initial filtration time reaches the maximum allowable time and still fails to meet the requirements: ;

[0266] The system triggers an alarm indicating that the initial filter is not up to standard and enters a maintenance or waiting-for-manual-confirmation state.

[0267] After the initial filtration is successful, the system closes the valves related to the initial filtration discharge, opens the filtered water regulating valve, and switches the filter tank status back to production filtration. Upon resuming production, the system resets the current filtration timer. ;

[0268] The system re-establishes the head blockage baseline, using the current blockage pooling value as the new initial state for filtration:

[0269] ;

[0270] Subsequent congestion growth is calculated as follows: ;

[0271] The system simultaneously records the start time, end time, triggering reason, flushing duration, pre-flushing blockage value, post-flushing blockage value, initial filtration duration, and initial filtration pass status of this backwash. After completing the above actions, the filter re-enters a closed-loop process of data acquisition, pretreatment, pooling calculation, constant water level filtration control, trend analysis, and backwash judgment.

[0272] Throughout the filtration, backwashing, and pre-filtration processes, the system continuously monitors the consistency between valve commands and feedback. If, after issuing a valve opening command, no feedback indicating the valve is fully open is received within a set time, the valve is determined to be incompletely open.

[0273] ;

[0274] in, This is a valve opening command. To ensure proper feedback, This refers to the valve opening waiting time.

[0275] If the system issues a valve closing command and does not receive feedback indicating that the valve is fully closed within a set time, the valve is determined to be incompletely closed. ;

[0276] If the same valve simultaneously shows both open and closed feedback: The system determined that there was a valve feedback conflict.

[0277] For the filtered water regulating valve, the system compares the valve setpoint with the feedback value: .

[0278] If the deviation continues to exceed the alarm delay, the system determines that the regulating valve tracking is abnormal.

[0279] If, during the flushing process, issues arise such as valve misalignment, insufficient backwash airflow, insufficient backwash water flow, abnormal liquid level, malfunctioning exhaust valve, substandard pre-filter, or abnormal resources, the system enters a flushing fault state. Upon entering this state, the system maintains the "flushing started but not completed" status flag, stops proceeding to the next step, and closes or maintains relevant valves according to safety protocols. Simultaneously, the filter tank is placed in maintenance mode, prohibiting its direct return to production filtration.

[0280] After handling an on-site fault, the operator can perform a reset on the fault reset interface. After resetting, the system rechecks the current valve status, liquid level status, backwash resource status, and flushing completion flag. If flushing is not complete, the system restarts the flushing process or resumes from an authorized safety procedure; if the operator selects disabled or test mode, the system exits the automatic flushing recovery logic.

[0281] A wastewater filter control system based on time-series analysis and pooling operation includes:

[0282] The host computer is used to receive login information, display the filter tank's operating status and alarm status, and send operating parameters to the PLC;

[0283] Online instruments are used to collect filter process variables and backwashing process variables, and send the collected data to the PLC through a communication module.

[0284] The PLC is used to execute the above-mentioned wastewater filter control method based on time-series analysis and pooling operation, which performs validity judgment on the collected data, forms valid time-series data, establishes a sliding time window, calculates pooling characteristic values, executes constant water level filtration control, judges backwashing requirements and controls the backwashing sequence.

[0285] The valve actuator is used to drive the valves related to filtration, backwashing, venting and primary filtration discharge according to the valve commands output by the PLC, and to feed back the valve position status to the PLC.

[0286] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

[0287] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wastewater filter control method based on time-series analysis and pooling operation, characterized in that, include: Read the filter bed operating parameters and scan the status of on-site equipment; determine the executable control process based on login permissions, filter bed working mode and automatic control access conditions. The PLC collects filter process variables according to the sampling period, and judges the range, change amplitude, dead zone and missing value of the collected value to obtain effective time series data. A sliding time window is established based on the effective time series data, and pooling feature values ​​are calculated. Based on the pooling characteristic values, constant water level filtration control is performed, and filtration stability, head blockage trend, turbidity time series and backwashing requirements are judged. When the backwash triggering conditions are met, backwash resources are confirmed, and flushing, primary filtration, and production resumption are performed according to the backwash sequence. The restored filter is then reintegrated into the closed-loop control.

2. The wastewater filter control method according to claim 1, characterized in that, Read the filter's operating parameters and scan the status of on-site equipment. Based on login permissions, filter operating mode, and automatic control access conditions, determine the executable control procedures, including: After the PLC, host computer, communication module, online instruments and valve actuators are initialized, the PLC reads the operating control parameters, including filter operation parameters, valve control parameters, flushing sequence parameters, liquid level adjustment parameters and time sequence analysis parameters. PLC scanning includes the status of field equipment, including field detection equipment, valve actuators, and backwashing actuators, and establishes a time-series data cache for process variables involved in the calculation; Based on login permissions and the current operating mode of the filter, determine the permitted filtration control, level regulation, backwashing, forced rinsing, or manual test procedures. Before entering the automatic control process, confirm that the filter is not disabled, the key valves are not seriously faulty, the liquid level has not reached the limit alarm, the backwash resources are not occupied, and the communication and instrument data are valid.

3. The wastewater filter control method according to claim 2, characterized in that, The PLC collects filter process variables according to the sampling period, and performs range, variation amplitude, dead zone, and missing value judgments on the collected values ​​to obtain valid time series data, including: The PLC collects filter process variables including liquid level, valve status, flow rate, head blockage value and water quality parameters, and writes the collected value of any variable at the current moment into the corresponding time-series data buffer. Compare the current collected value with the corresponding instrument's allowable range. If the value exceeds the allowable range, mark it as an invalid value and prohibit it from participating in the pooling calculation for this cycle. When the current acquired value is within the allowable range, compare the current acquired value with the previous valid value. If the difference exceeds the maximum allowable single-cycle change, mark it as a jump anomaly and maintain the previous valid value or generate an instrument anomaly status based on the duration of the anomaly. When the difference between the current collected value and the previous valid value is less than the set dead zone, the previous valid value is retained as the valid value for this period. If the instrument fails to upload data for a short period of time, the previous valid value will be used to maintain the calculation. If the missing time exceeds the set allowable value, the corresponding variable will be prohibited from participating in critical automatic control.

4. The wastewater filter control method according to claim 3, characterized in that, Based on the effective time-series data, a sliding time window is established and pooling feature values ​​are calculated, including: For any process variable involved in the calculation, the N most recent valid sampled values ​​are taken at the current moment to form a sliding time window; When a new valid sample value enters the sliding time window, the earliest valid sample value is removed, so that the sliding time window remains at a fixed length. Calculate the smoothing characteristics, trend characteristics, and fluctuation characteristics of liquid level based on the liquid level sliding time window; Calculate the characteristics of blockage degree and blockage trend based on the sliding time window of the water head blockage value; Water quality smoothness characteristics, peak water quality characteristics, trend water quality characteristics, and fluctuation water quality characteristics are calculated based on turbidity sliding time windows. Based on the sliding time window of the execution volume and backwash process variables, the valve load characteristics, backwash air volume characteristics, and backwash water volume characteristics are calculated.

5. The wastewater filter control method according to claim 4, characterized in that, Performing constant water level filtration control based on the pooling characteristic values ​​includes: When the filter is in production filtration mode, read the level smoothing characteristics and the current effective level value, and calculate and control the level according to the set weight; Calculate the liquid level deviation based on the set liquid level and the controlled liquid level; When the absolute value of the liquid level deviation is less than the set liquid level dead zone, keep the current opening of the filtered water regulating valve unchanged; When the absolute value of the liquid level deviation is not less than the set liquid level dead zone, the adjustment output is calculated based on the current liquid level deviation, historical liquid level deviation, sampling period and PID parameters. The setpoint value of the filter water regulating valve is obtained by superimposing the regulating output with the basic opening degree, and the opening degree setpoint value is limited by the opening degree amplitude and the change amount between adjacent cycles. The PLC converts the limited opening setpoint into an analog signal and outputs it to the filtered water regulating valve.

6. The wastewater filter control method according to claim 5, characterized in that, Determine filtration stability, head clogging trend, turbidity time series, and backwashing requirements, including: The stability of filtration is determined by the difference between the controlled liquid level and the set liquid level, the characteristics of liquid level fluctuation, and the output change of the filtered water regulating valve in adjacent cycles. When the control liquid level deviates from the set liquid level for a long period of time and the opening of the filtered water regulating valve is close to the opening limit, an abnormal filtration state is generated and sent to the backwash judgment process. The blockage status is determined based on the blockage degree characteristics and blockage trend characteristics, and the remaining time to reach the blockage backwash set value is calculated when the blockage trend characteristics indicate that the head blockage value is rising. The quality status of the effluent is determined based on the smoothness characteristics, peak characteristics, trend characteristics, and fluctuation characteristics of the water quality. Scoring items are calculated based on cumulative filtration time, clogging degree characteristics, clogging trend characteristics, water quality smoothness characteristics, and valve load characteristics, and then weighted to obtain a comprehensive backwash score.

7. The wastewater filter control method according to claim 6, characterized in that, When the anti-washing trigger conditions are met, confirm the anti-washing resources, including: A backwash request is generated when any one of the following conditions is met: cumulative filtration time, blockage degree characteristics, water quality smoothness characteristics, remaining time, or comprehensive backwash score; When no backwash request is generated, maintain the production filtration status and continue to perform data acquisition, preprocessing, sliding time window update, pooling calculation and constant water level filtration control. After generating a backwash request, determine whether backwash resources, including backwash water supply equipment, backwash gas supply equipment, backwash pipelines, drainage and public facilities, are available. When backwashing resources are available, lock the current filter backwashing process and prevent other filters from occupying the locked resources; When the anti-washing resource is unavailable, it enters the anti-washing waiting state and accumulates the waiting time. When the waiting time reaches the maximum waiting time, an anti-washing waiting timeout state is generated.

8. The wastewater filter control method according to claim 7, characterized in that, Perform rinsing according to the backwash sequence, including: After the backwash resources are locked, the filter-related valves are switched to the backwash preparation state in sequence, and the corresponding valves are waited for feedback on their position. If any valve fails to receive feedback on the target arrival within the set valve action time, a valve action timeout state is generated and a flushing fault state is entered. When the relevant filtration valves are in place and the liquid level is within the allowable range, the air washing stage begins. During the air washing stage, the backwash air supply path is opened and the backwash air supply equipment is started. The backwash air volume is collected and the backwash air volume characteristics are calculated. When the backwash air volume characteristics do not meet the air washing requirements and continue to exceed the alarm delay, the flushing fault state is entered. After the air washing time reaches the set air washing time, the backwash water supply path is opened and the backwash water supply equipment is started to enter the air-water combined flushing stage; After the combined air-water flushing time reaches the set time, the backwash air supply path is closed, the backwash air supply equipment is stopped, and the water rinsing stage begins. After the water rinsing time reaches the set time, the exhaust stage begins.

9. The wastewater filter control method according to claim 8, characterized in that, Perform initial filtration and production recovery according to the backwashing sequence, and reintegrate the recovered filter into the closed-loop control system, including: During the exhaust phase, the exhaust valve is opened and the exhaust time is accumulated. After the exhaust time reaches the set exhaust time, the exhaust valve is closed and feedback on whether it is closed is received. If the exhaust valve fails to close completely within the set time, an exhaust valve malfunction status is generated and the flushing malfunction status is entered. After the vent valve is closed, the control valve for the inlet water and the valves related to the primary filter discharge will enter the primary filtration stage; Collect water quality parameters of the primary filtered water and calculate the smoothness characteristics and fluctuation characteristics of the primary filtered water. When the initial filtration water quality smoothness characteristics, initial filtration water quality fluctuation characteristics, and initial filtration duration meet the initial filtration qualification conditions, the production resumption stage begins. If the initial filtration duration reaches the maximum allowable time and still fails to meet the requirements, an initial filtration failure status is generated and the system enters maintenance or waiting for manual confirmation status. When production resumes, close the valves related to the primary filter discharge, open the filtered water regulating valve, reset the cumulative filtration time to zero, use the current blockage characteristics as the new head blockage benchmark, and re-execute closed-loop control.

10. A wastewater filter control system based on time-series analysis and pooling operation, characterized in that, include: The host computer is used to receive login information, display the filter tank's operating status and alarm status, and send operating parameters to the PLC; Online instruments are used to collect filter process variables and backwashing process variables, and send the collected data to the PLC through a communication module. The PLC is used to execute the method described in any one of claims 1 to 9, which includes judging the validity of collected data, forming valid time-series data, establishing a sliding time window, calculating pooling characteristic values, executing constant water level filtration control, judging backwashing requirements and controlling the backwashing sequence. The valve actuator is used to drive the valves related to filtration, backwashing, venting and primary filtration discharge according to the valve commands output by the PLC, and to feed back the valve position status to the PLC.

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