Single water tank multi-well catchment system control method and system

Abstract

The present application relates to the technical field of water supply control, and discloses a single-water-tank multi-well water collection system control method and system, which is suitable for the automatic control scene of water supply of multiple water wells to the same water collection tank, and comprises the following steps: collecting or receiving the real-time liquid level of the water tank, the flow of each well and the water outlet flow at the rear end of the water tank formed by direct collection of field sensors, obtaining the total water inlet flow, and forming a dynamic equivalent cross-sectional area sample according to the total water inlet flow, the water outlet flow at the rear end of the water tank and the change of the real-time liquid level of the water tank at the adjacent sampling time; when the sample meets the direction consistency, distinguishability and signal effectiveness check, a liquid level-dynamic equivalent cross-sectional area fingerprint is generated, and then the liquid level difference between the current real-time liquid level of the water tank and the target liquid level is converted into a volume deviation, the total water inlet demand is determined according to the volume deviation and the water outlet flow at the rear end of the water tank, and the well pump group start-stop command and the variable frequency frequency command are output.

Description

Technical Field

[0001] This invention belongs to the field of water supply control technology, specifically relating to a control method and system for a single-tank multi-well water collection system. Background Technology

[0002] Single-tank multi-well water collection systems are commonly used for centralized water supply from multiple wells. On-site, a programmable logic controller (PLC) or industrial controller is typically connected to the tank's level sensor, flow meters for each well, the outlet flow meter at the tank's rear, pressure detection, motor protection, well pump operation feedback, fault feedback, frequency converter, contactor, and touchscreen to complete well pump start / stop, variable frequency speed control, pump rotation, and safety interlocks. During commissioning, the target level, normal level range, and high / low level boundaries are generally used as the primary criteria, along with start / stop delays, minimum operating time, minimum downtime, and fault reselection, to maintain the tank within the allowable level range.

[0003] During on-site operation, the water storage volume corresponding to a unit change in the tank level will be affected by the tank's shape, conical bottom, rounded bottom, the space occupied by internal fasteners, and the installation status. If the controller is still adjusted according to a fixed level deviation, fixed gain, and fixed frequency ramp, the water replenishment demand corresponding to the same level difference will be different in different level ranges, which may result in insufficient water replenishment, level overshoot, repeated adjustments, or an increase in the number of well pump switching times.

[0004] Furthermore, in multi-well water supply scenarios, the flow rate of each well, the outflow rate at the rear of the water tank, and the availability status of the well pumps change over time. Simply relying on the liquid level threshold is insufficient to reflect the relationship between the current water volume change in the water tank and the water load. Engineeringly, a control method is needed that operates based on existing sensors, well pumps, frequency converters, and safety interlocks. This method would allow field-collected data to participate in determining the water tank's storage volume and the well pump's adjustment scale, and would revert to existing liquid level control in the event of signal anomalies or safety interlock triggering. Summary of the Invention

[0005] The present invention aims to provide a control method and system for a single-tank multi-well water collection system, which solves the technical problems mentioned in the background art.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution.

[0007] A control method for a single-tank, multi-well water collection system, applicable to a single-tank, multi-well water collection system with a water collection tank, well pump set, and control device, including:

[0008] The control device periodically collects or receives the real-time liquid level of the water tank, the flow rate of each well, and the outflow rate of the water tank from the rear end, which are directly collected by the field sensors, and obtains the total inflow rate based on the flow rate of each well.

[0009] Based on the total inflow rate, the outflow rate at the rear end of the water tank, and the real-time liquid level change of the water tank at adjacent sampling times, a dynamic equivalent cross-sectional area sample is determined. When the direction of the real-time liquid level change of the water tank is consistent with the direction of the net flow rate determined by the difference between the total inflow rate and the outflow rate at the rear end of the water tank, the real-time liquid level change of the water tank is within the resolvable range of the water tank level sensor, and the real-time liquid level of the water tank, the total inflow rate, and the outflow rate at the rear end of the water tank pass the signal validity check, the dynamic equivalent cross-sectional area sample is taken as a valid sample.

[0010] Based on the valid samples, a liquid level-dynamic equivalent cross-sectional area structural fingerprint containing an equivalent cross-sectional area function and a structural change rate is generated.

[0011] Based on the liquid level-dynamic equivalent cross-sectional area structure fingerprint, the liquid level difference between the current real-time liquid level in the water tank and the target liquid level is converted into a volume deviation;

[0012] The total water intake demand is determined based on the volume deviation and the water flow rate at the rear end of the water tank. The start / stop command of the well pump group is determined based on the total water intake demand. The adaptive frequency limit value of the structure is determined based on the equivalent cross-sectional area function and the structural change rate. The adaptive frequency limit value of the structure is used to limit the allowable change range of the frequency conversion command relative to the previous control cycle.

[0013] Compared with the prior art, the present invention has the following substantial features and significant progress:

[0014] This invention, while retaining the existing configuration of water tank, well pump, pipeline, sensor, and control device, introduces a liquid level-dynamic equivalent cross-sectional area fingerprint formed by the real-time liquid level of the water tank, the total inflow rate, and the outflow rate at the rear end of the water tank. This fingerprint converts the liquid level difference between the current real-time liquid level of the water tank and the target liquid level into a volume deviation, and determines the total inflow demand, well pump start / stop commands, and frequency conversion commands accordingly. This ensures that the well pump adjustment matches the actual water storage volume change of the water tank. In operating conditions where the liquid level response is sensitive or the water storage volume changes significantly, this invention can reduce the probability of liquid level overshoot, repeated adjustments, and frequent well pump switching. At the same time, it prioritizes safety interlocks such as high-high liquid level, low-low liquid level, overcurrent, overtemperature, overpressure, dry running, communication interruption, and frequency converter failure. Attached Figure Description

[0015] Figure 1 This is a diagram of the control system module and control mechanism of the single-tank multi-well water collection system of the present invention. Detailed Implementation

[0016] The following description is provided in conjunction with the accompanying drawings. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the invention; those skilled in the art can make equivalent substitutions or combinations for the specific implementations.

[0017] Figure 1 The diagram shows the connection relationships between the water collection tank 100, the water tank level sensor 110, the water outlet pipe 120 at the rear of the water tank, the water outlet flow meter 130 at the rear of the water tank, the float switch 140, the pressure sensor 150, the well group 200, the well pump group 210, the flow meters of each well 220, the inlet manifold 230, the frequency converter 240, the contactor 250, the motor protection signal input 260, the communication status input 270, and the control device 300. Figure 1 The control device 300 also includes a basic signal acquisition module 310, a structural sample calculation module 320, a structural fingerprint storage module 330, a volume deviation conversion module 340, a structural adaptive control module 350, a pump group sequence control module 360, and a safety interlock module 370.

[0018] This embodiment is applicable to a single-tank multi-well water collection system with a water collection tank, well pump set, and control device. This single-tank multi-well water collection system can be deployed in sites such as mine drainage, centralized water supply, production circulating water replenishment, groundwater collection, or other locations where multiple wells supply water to the same water collection tank. Water from the multiple wells is transported by well pump set 210 to inlet manifold 230, which then collects the water from each well into water collection tank 100. Water collection tank 100 supplies water to downstream water-using equipment or subsequent pipe networks through outlet pipe 120 at the rear of the tank. The control device 300 uses the real-time water level of the tank, the flow rate of each well, and the outlet flow rate at the rear of the tank as the basic data for direct acquisition or reception. While maintaining the original tank, well pump set, and pipeline structure unchanged, it controls the start / stop commands of the well pump set and the frequency conversion commands.

[0019] In existing single-tank multi-well water collection systems, the control device typically compares the difference between the current liquid level and the target liquid level directly, and controls the well pump group 210 based on fixed proportional-integral-derivative parameters, fixed proportional-integral parameters, or fixed frequency changes. When the water collection tank 100 has different effective capacities in different real-time liquid level ranges, the same liquid level difference may correspond to different water storage volume differences. If control is still performed using a fixed liquid level control mode, in the real-time liquid level range of the tank with a smaller equivalent cross-sectional area, a small amount of total inflow may cause a significant change in the real-time liquid level of the tank; in the real-time liquid level range of the tank with a larger equivalent cross-sectional area, the same real-time liquid level change may correspond to a larger change in water storage volume. This embodiment uses the total inflow, the outflow at the rear of the tank, and the real-time liquid level change of the tank at adjacent sampling times to determine the dynamic equivalent cross-sectional area sample, enabling the control device 300 to obtain the liquid level-dynamic equivalent cross-sectional area structural fingerprint, and further perform volume deviation conversion, total inflow demand determination, and structural adaptive frequency limit determination.

[0020] like Figure 1As shown, the well group 200 may include a first well 201, a second well 202, and a third well 203; the well pump group 210 may include a first well pump 211, a second well pump 212, and a third well pump 213; and the flow meters 220 for each well may include a first well flow meter 221, a second well flow meter 222, and a third well flow meter 223. The first well pump 211, the second well pump 212, and the third well pump 213 respectively deliver water from the first well 201, the second well 202, and the third well 203 into the inlet manifold 230. The first well flow meter 221, the second well flow meter 222, and the third well flow meter 223 respectively output the flow rate of their respective wells. Figure 1 Only three wells are shown as an example for ease of explanation. The number of wells in the well group 200 can be determined according to the number of existing wells on site. The number of well pumps in the well pump group 210 is configured accordingly to the number of flow meters in each well flow meter 220.

[0021] The water collection tank 100 is the storage container for water collected from multiple wells. A water level sensor 110 is installed on the side wall or top of the water collection tank 100 to output the real-time water level. A flow meter 130 is installed on the rear outlet pipe 120 of the water tank to output the rear outlet flow rate. A float switch 140 is installed on the water collection tank 100 to generate safety status inputs such as high / high or low / low water levels. A pressure sensor 150 is installed on the rear outlet pipe 120 of the water tank to generate overpressure-related inputs. A motor protection signal input 260 provides overcurrent, overtemperature, or dry-running related signals to the safety interlock module 370, and a communication status input 270 provides communication interruption related signals to the safety interlock module 370. All of the above hardware can use conventional industrial components from existing single-tank multi-well water collection systems; the improvements in this embodiment do not depend on specific brands, specific communication protocols, or specific register addresses.

[0022] The control device 300 can be a programmable logic controller (PLC) or an industrial controller with periodic data acquisition, data calculation, command output, and safety interlock processing capabilities. The basic signal acquisition module 310, structural sample calculation module 320, structural fingerprint storage module 330, volume deviation conversion module 340, structural adaptive control module 350, pump group sequence control module 360, and safety interlock module 370 can be implemented as function blocks, subroutines, task segments, register areas, or software objects in the PLC program, or they can be jointly implemented by the host control software and the field controller. The above module division is used to illustrate functional boundaries and does not require the physical installation of seven independent controllers.

[0023] The complete control framework of this implementation is as follows: the basic signal acquisition module 310 directly acquires or receives the real-time liquid level of the water tank, the flow rate of each well, and the outflow rate of the water tank from the rear end, which are directly acquired by field sensors, and obtains the total inflow rate based on the flow rate of each well; the structural sample calculation module 320 determines the dynamic equivalent cross-sectional area sample based on the total inflow rate, the outflow rate of the water tank from the rear end, and the real-time liquid level change of the water tank at adjacent sampling times, and uses the dynamic equivalent cross-sectional area sample as a valid sample when it meets the requirements of consistent direction, resolvable range, and signal validity checks; the structural fingerprint storage module 330 generates a function containing the equivalent cross-sectional area function and... The liquid level-dynamic equivalent cross-sectional area structural fingerprint of the structural change rate; the volume deviation conversion module 340 converts the liquid level difference between the current real-time liquid level and the target liquid level into volume deviation based on the liquid level-dynamic equivalent cross-sectional area structural fingerprint; the structural adaptive control module 350 determines the total water intake demand, the structural adaptive frequency limit value, and the frequency conversion command based on the volume deviation, the water flow rate at the rear end of the water tank, the equivalent cross-sectional area function, and the structural change rate; the pump group sequence control module 360 ​​determines the well pump group start and stop commands based on the total water intake demand; the safety interlock module 370 overrides the well pump group start and stop commands and the frequency conversion command when the safety interlock is triggered.

[0024] Figure 1 The well group 200 on the left represents the water supply source in a single-tank multi-well water collection system. The first well 201, the second well 202, and the third well 203 are connected to the first well pump 211, the second well pump 212, and the third well pump 213, respectively. Each well pump's outlet side is equipped with a first well flow meter 221, a second well flow meter 222, and a third well flow meter 223, respectively. The three flow streams converge into the water collection tank 100 via the inlet manifold 230. This connection ensures that the flow rate of each well can be identified by the basic signal acquisition module 310 and used to calculate the total inlet flow rate. If more than three wells are configured on-site, the control device 300 reads the flow rate of each well in the same manner and sums all valid flow rates.

[0025] Figure 1 The water collection tank 100 is located between the well group 200 and the outlet pipe 120 at the rear of the tank, and is the physical object that generates real-time changes in the water level of the tank. The real-time water level output by the water tank level sensor 110 reflects the water level status corresponding to the water volume stored in the water collection tank 100. The water flow rate output by the outlet flow meter 130 at the rear of the tank reflects the flow rate output by the water collection tank 100 to the downstream water-using equipment.

[0026] Figure 1The control device 300 on the right represents the software and hardware carriers that execute the control method of this embodiment. The basic signal acquisition module 310 receives data from the water tank level sensor 110, the flow meters 220 of each well, and the water tank rear outlet flow meter 130. The structural sample calculation module 320 receives the real-time water tank level, total inflow rate, and water tank rear outlet flow rate output by the basic signal acquisition module 310. The structural fingerprint storage module 330 receives valid samples output by the structural sample calculation module 320 and provides the equivalent cross-sectional area function and structural change rate to the volume deviation conversion module 340 and the structural adaptive control module 350. The volume deviation conversion module 340 outputs the volume deviation to the structural adaptive control module 350. The structural adaptive control module 350 outputs the total inflow demand to the pump group sequence control module 360 ​​and outputs the frequency conversion command to the frequency converter 240. The pump group sequence control module 360 ​​outputs the well pump group start / stop command to the contactor 250. The safety interlock module 370 receives inputs from the float switch 140, pressure sensor 150, motor protection signal input 260, and communication status input 270, and overrides relevant commands from the structure adaptive control module 350, pump group sequence control module 360, frequency converter 240, and contactor 250 when the safety interlock is triggered.

[0027] Figure 1 The dashed arrows in the diagram can be interpreted as data acquisition paths, solid arrows as control command paths, and dotted-dashed arrows as safety interlock coverage paths. This diagram shows that this implementation combines field sensor acquisition, internal calculations by the control device 300, execution by the well pump unit 210, drive by the frequency converter 240, start / stop by the contactor 250, and coverage by the safety interlock module 370 into a closed-loop control process. In specific implementation, the control device 300 cyclically executes the functions of each module according to a fixed sampling period, enabling... Figure 1 The data and commands shown are updated within each control cycle.

[0028] Furthermore, Figure 1In this embodiment, the data acquisition path corresponds to the following defined relationship: the water tank level sensor 110 sends the real-time water tank level to the basic signal acquisition module 310, the flow meters 220 of each well send the flow rate of each well to the basic signal acquisition module 310, the water tank rear outlet flow meter 130 sends the water tank rear outlet flow rate to the basic signal acquisition module 310, and the basic signal acquisition module 310 sends the total inflow flow rate, along with the real-time water tank level and the water tank rear outlet flow rate, to the structural sample calculation module 320. The structural sample calculation module 320 sends the dynamic equivalent cross-sectional area sample and the effective sample to the structural fingerprint storage module 330. The structural fingerprint storage module 330 sends the equivalent cross-sectional area function and the structural change rate to the volume deviation conversion module 340 and the structural adaptive control module 350. The volume deviation conversion module 340 sends the volume deviation to the structural adaptive control module 350. The structural adaptive control module 350 sends the total water intake demand to the pump group sequence control module 360, uses the structural adaptive frequency limiting value to generate the frequency conversion command, and sends the frequency conversion command to the frequency converter 240. The pump group sequence control module 360 ​​sends the well pump group start and stop command to the contactor 250. The safety interlock module 370 sends the safety interlock overlay signal to the structural adaptive control module 350, the pump group sequence control module 360, the frequency converter 240, and the contactor 250.

[0029] The basic signal acquisition module 310 is used to directly acquire or receive the real-time water tank level, flow rate of each well, and water outflow rate at the rear end of the water tank, which are directly acquired by field sensors, and to obtain the total inflow rate. The real-time water tank level is generated by the water tank level sensor 110 and can be input to the control device 300 via analog input, digital communication input, or fieldbus input. The flow rate of each well is generated by the flow meters 220 of each well, which can correspond to the outputs of the first well flow meter 221, the second well flow meter 222, and the third well flow meter 223, respectively. The water outflow rate at the rear end of the water tank is generated by the water outflow meter 130 at the rear end of the water tank and serves as a direct representation of the actual output state at the rear end of the water collection tank 100.

[0030] During each control cycle, the basic signal acquisition module 310 reads the real-time liquid level of the water tank. Read the first Flow rates of each well corresponding to the saliva well Read the water flow rate at the rear of the water tank. The same controller timestamp is appended to the data within the same control cycle. If the control device 300 uses a time synchronization acquisition module, the same controller timestamp is generated by the system clock of the control device 300; if the control device 300 reads multiple input points in steps, the basic signal acquisition module 310 can temporarily store each input value within a fixed sampling period and use the sampling time of the fixed sampling period as the same controller timestamp.

[0031] The basic signal acquisition module 310 obtains the total inflow rate based on the flow rate of each well. For wells with... The total inflow rate of a single-tank multi-well water collection system for a septic tank can be determined using the following formula:

[0032]

[0033] in, Indicates the first Total inflow rate for each control cycle Indicates the first Within the first control cycle, the first The flow rate of each well corresponding to the saliva well. This indicates the number of wells involved in the summation. If the flow rate of each well corresponding to a certain well fails the signal validity check, the basic signal acquisition module 310 can mark the flow rate of each well as invalid and output this status to the structural sample calculation module 320 and the safety interlock module 370 to prevent invalid flow rates of each well from entering the dynamic equivalent cross-sectional area sample calculation.

[0034] The signal validity check includes range status checks, communication status checks, and timestamp consistency checks on the real-time water tank level, total inflow rate, and outflow rate at the rear of the water tank. The range status check determines whether the real-time water tank level is within the effective range of the water tank level sensor 110, whether the total inflow rate is within the allowable engineering range of each well flowmeter 220 and well pump group 210, and whether the outflow rate at the rear of the water tank is within the effective range of the outflow meter 130 at the rear of the water tank. The communication status check determines whether there are communication interruptions, communication timeouts, verification errors, or data freezes between the relevant sensors and the control device 300. The timestamp consistency check determines whether the real-time water tank level, total inflow rate, and outflow rate at the rear of the water tank correspond to the same control cycle or allowable sampling time window.

[0035] The range status check can be performed jointly based on the range on the sensor nameplate, the engineering range loaded in the control device 300, and the current available capacity of the well pump group 210. For the real-time water tank level, the basic signal acquisition module 310 confirms that the real-time water tank level is not lower than the lower limit of the range of the water tank level sensor 110 and not higher than the upper limit of the range of the water tank level sensor 110; for the total inflow rate, the basic signal acquisition module 310 confirms that the total inflow rate is not less than zero and not greater than the maximum total inflow rate corresponding to the current available well pump status; for the outflow rate at the rear of the water tank, the basic signal acquisition module 310 confirms that the outflow rate at the rear of the water tank is not less than zero and not higher than the upper limit of the range of the outflow meter 130 at the rear of the water tank. If the field flow meter allows reverse flow detection, the reverse flow status is not used as a valid sample calculation input, but is sent as an abnormal status to the safety interlock module 370 or the fixed level control mode.

[0036] Communication status checks can be performed according to a communication acknowledgment cycle. The communication acknowledgment cycle is denoted as... Its dimension is time, and its value is derived from the communication refresh cycle between the control device 300 and the field sensors. Specifically, it can be set to... to Alternatively, it can be set to an existing communication timeout parameter on site. When the time interval between the latest valid data of the water tank level sensor 110, the flow meters of each well 220, or the water outlet flow meter 130 at the rear of the water tank and the current control cycle is greater than the communication confirmation cycle, the corresponding signal will not pass the communication status check.

[0037] Timestamp consistency checks can be performed according to the allowed deviation for timestamp consistency. The allowed deviation for timestamp consistency is denoted as... Its unit is time, and its value can be no greater than a fixed sampling period, i.e. Within the same control cycle, if the difference between the maximum and minimum sampling times corresponding to the real-time liquid level of the water tank, the total inflow rate, and the outflow rate at the rear of the water tank is not greater than the allowable deviation for timestamp consistency, the timestamp consistency check is deemed passed; otherwise, the basic signal acquisition module 310 marks the data of this cycle as asynchronous, and the structural sample calculation module 320 does not use the dynamic equivalent cross-sectional area sample of this cycle as a valid sample.

[0038] The basic signal acquisition module 310 can also read the pump frequency, pressure, current, temperature, operation feedback, fault status, and float status. These device statuses are used by the safety interlock module 370, the pump sequence control module 360, and the operation record, and are not considered as additional application scenario parameters required to form the liquid level-dynamic equivalent cross-sectional area structure fingerprint. In specific implementation, the pressure sensor 150 can provide an overpressure judgment signal, the float switch 140 can provide a high-high liquid level or low-low liquid level judgment signal, the motor protection signal input 260 can provide an overcurrent, overtemperature, or dry-run judgment signal, and the communication status input 270 can provide a communication interruption judgment signal.

[0039] The structural sample calculation module 320 is used to determine the dynamic equivalent cross-sectional area sample based on the total inflow rate, the outflow rate at the rear end of the water tank, and the real-time liquid level change of the water tank. This dynamic equivalent cross-sectional area sample reflects the change in water storage volume corresponding to a unit real-time liquid level change in the water collection tank 100 near the current real-time liquid level. This dynamic equivalent cross-sectional area sample is not directly given by the nominal drawing dimensions of the water collection tank 100, nor does it require the addition of structural components inside the water collection tank 100. Instead, it is derived by the control device 300 from the on-site operating data.

[0040] In terms of continuous physical relationships, the water storage volume within the 100-cell water collection tank... The rate of change is equal to the total inflow rate. Water flow rate at the rear of the water tank The difference between them. This relationship can be represented as:

[0041]

[0042] in, Indicates time Total inflow rate, Indicates time The water flow rate at the rear end of the water tank Indicates time The formula is based on the law of conservation of mass, ignores short-cycle evaporation, and considers leakage as part of the actual flow rate.

[0043] There is a coupling relationship between the change in water volume of the water collection tank 100 and the real-time change in the tank's liquid level. The dynamic equivalent cross-sectional area near the current real-time liquid level of the tank is represented as... Then we have:

[0044]

[0045] in, Indicates time The dynamic equivalent cross-sectional area corresponding to the real-time liquid level of the water tank. Indicates time The formula above indicates that, under the same change in water volume, the magnitude of the change in the real-time water level of the tank is affected by the effective capacity scale near the current real-time water level.

[0046] After establishing the above relationships, we can obtain a continuous expression for the dynamic equivalent cross-sectional area:

[0047]

[0048] Among them, molecules The denominator represents the difference in flow rate between the water entering and leaving the water collection tank 100. This represents the real-time liquid level change rate of the water tank. When the real-time liquid level change of the water tank corresponding to the denominator is too small or indistinguishable, the structural sample calculation module 320 does not use this control cycle to form a new dynamic equivalent cross-sectional area sample.

[0049] When the control device 300 operates according to a fixed sampling period, the structural sample calculation module 320 uses discrete expressions to determine the dynamic equivalent cross-sectional area sample:

[0050]

[0051] in, Indicates the first The dynamic equivalent cross-sectional area sample is generated in each control cycle. Indicates the first Total inflow rate for each control cycle Indicates the first The water flow rate at the back end of the water tank during each control cycle Indicates a fixed sampling period. Indicates the first Real-time water tank level for each control cycle This represents the real-time liquid level of the water tank in the previous control cycle. This discrete expression uses only the real-time liquid level of the water tank, the total inlet flow rate, the outlet flow rate at the rear of the water tank, and the existing fixed sampling cycle of the control device 300.

[0052] To prevent abnormal transition data from entering the liquid level-dynamic equivalent cross-sectional area structural fingerprint, the structural sample calculation module 320 needs to determine whether the direction of real-time liquid level change in the tank is consistent with the direction of net flow determined by the difference between the total inflow rate and the outflow rate at the rear of the tank. This determination can be expressed by the following conditions:

[0053]

[0054] Specifically, if the total inflow rate is greater than the outflow rate at the rear end of the water tank, the net flow direction determined by the difference between the total inflow rate and the outflow rate corresponds to an increase in the water volume stored in the collection tank 100, and the real-time liquid level change in the tank should be an increase. Conversely, if the total inflow rate is less than the outflow rate at the rear end of the water tank, the net flow direction determined by the difference between the total inflow rate and the outflow rate corresponds to a decrease in the water volume stored in the collection tank 100, and the real-time liquid level change in the tank should be a decrease. Only when both directions are consistent can the dynamic equivalent cross-sectional area sample possess physical consistency for describing the capacity structure of the collection tank 100.

[0055] The real-time liquid level change in the water tank reaches the resolvable range of the water tank level sensor 110, which is another limitation for using the dynamic equivalent cross-sectional area sample as a valid sample. If If the absolute value of the change is less than the minimum resolvable change by the water tank level sensor 110, the denominator of the discrete expression is easily affected by sensor noise, and the structural sample calculation module 320 will not consider the dynamic equivalent cross-sectional area sample formed during this control cycle as a valid sample. If the real-time water tank level, total inflow rate, and outflow rate at the rear of the water tank pass the signal validity check, and both the conditions of consistent direction and resolvable range are met, then the structural sample calculation module 320 will consider the dynamic equivalent cross-sectional area sample as a valid sample and output the valid sample to the structural fingerprint storage module 330.

[0056] The resolvable range of the water tank level sensor 110 is denoted as: Its dimension is length, and its value is derived from the device resolution of the water tank level sensor 110, the analog conversion resolution of the control device 300, and the on-site static noise. In practice, the real-time water level of the water tank can be continuously collected when the well pump group 210 is stopped and the water flow rate at the rear end of the water tank is zero or remains stable, thus obtaining the standard deviation of the static noise. The resolvable range of the water tank level sensor 110 is determined according to the following formula:

[0057]

[0058] in, This indicates the resolvable range of the water tank level sensor 110. This indicates the device resolution after conversion of the engineering quantities for the water tank level sensor 110 or control device 300. This represents the standard deviation of static noise. The structural sample calculation module 320 is only available in... It is assumed that the real-time liquid level change in the water tank has reached the resolvable range of the water tank level sensor 110.

[0059] When the real-time water level, total influent flow rate, or outfluent flow rate at the rear of the water tank fails the signal validity check, or when the outfluent flow rate at the rear of the water tank cannot be directly collected by the field flow meter, or when the well pump has just started or stopped, or when the float switch 140 is triggered, the structural sample calculation module 320 pauses updating the liquid level-dynamic equivalent cross-sectional area structural fingerprint. When the well pump has just started or stopped, pipeline transients, changes in well pump speed, and flow meter response lag may cause a short-term mismatch between the total influent flow rate and the real-time water level change in the water tank; when the float switch 140 is triggered, the control target has already entered the safety boundary processing and is not suitable as a structural learning sample. Pausing the update only affects the writing of valid samples and does not prevent the safety interlock module 370 from performing overwrite control.

[0060] The structural fingerprint storage module 330 is used to generate a liquid level-dynamic equivalent cross-sectional area structural fingerprint, including an equivalent cross-sectional area function and a structural change rate, based on valid samples. After receiving valid samples output by the structural sample calculation module 320, the structural fingerprint storage module 330 sorts the valid samples according to the real-time liquid level of the water tank and writes the valid samples to the storage location corresponding to the real-time liquid level range of the water tank. This storage location can be a data block, register array, file record area, or other conventional data storage unit in the control device 300.

[0061] The effective sample set can be represented as:

[0062]

[0063] in, Represents the set of valid samples. Indicates the first Real-time water tank level for each control cycle Indicates the first Dynamic equivalent cross-sectional area samples for each control cycle. This represents the set of control cycles that meet the checks for directional consistency, resolvable range, and signal validity. The effective sample set is used to form the equivalent cross-sectional area function. It is not required to cover the entire real-time liquid level range of the water tank at once, and can be gradually supplemented as the single-tank multi-well water collection system operates.

[0064] The structural fingerprint storage module 330 performs averaging on valid samples from the same or adjacent real-time liquid level ranges of water tanks. Averaging can employ arithmetic mean, moving average, or existing sample smoothing methods in the control device 300. The purpose of averaging is to reduce the impact of short-term measurement noise from the water tank level sensor 110, the flow meters 220 at each well, and the water outlet flow meter 130 at the rear of the water tank on the equivalent cross-sectional area function. Since this averaging is only performed on valid samples that already meet the validity criteria, it does not include dynamically equivalent cross-sectional area samples with inconsistent orientations or indistinguishable orientations in the liquid level-dynamic equivalent cross-sectional area structural fingerprint.

[0065] The real-time liquid level range of the same water tank can be determined by the width of the liquid level range. The width of the liquid level interval is measured in units of length, and its value can be equal to or an integer multiple of the resolvable range of the water tank level sensor 110. The control device 300 divides the working liquid level range into multiple continuous real-time liquid level intervals for each water tank according to the width of the interval, and writes each valid sample into its corresponding real-time liquid level interval. If the real-time liquid level of a valid sample falls on the boundary between two real-time liquid level intervals, it is written into the lower real-time liquid level interval to ensure unique interval assignment.

[0066] The preferred averaging method is the arithmetic mean. Let the first... The number of valid samples in the real-time liquid level range of each water tank is The first of the real-time liquid level ranges in this water tank One dynamic equivalent cross-sectional area sample is Then the average dynamic equivalent cross-sectional area of ​​the real-time liquid level range of the water tank can be expressed as:

[0067]

[0068] in, Indicates the first The average dynamic equivalent cross-sectional area of ​​the real-time liquid level range of each water tank. Indicates the first The number of valid samples in the real-time liquid level range of each water tank. Indicates the first The first of the real-time liquid level ranges of the water tank A dynamic equivalent cross-sectional area sample. When When the value is zero, the average dynamic equivalent cross-sectional area of ​​the real-time liquid level range of the water tank is not generated temporarily, and is processed by the real-time liquid level range of the adjacent covered water tank or the fixed liquid level control mode.

[0069] When the control device 300 needs to limit the storage volume, the real-time liquid level range of each water tank can retain the most recent value. One valid sample, The number of samples to retain is determined by the storage capacity of the control device 300 and the fixed sampling period. Specifically, it can be... to After a new valid sample is written, if the number of valid samples in the real-time liquid level range of the tank exceeds the number of samples to be retained, the oldest valid sample is deleted, and the average dynamic equivalent cross-sectional area is recalculated. This process is a standard first-in-first-out (FIFO) maintenance method in the existing controller data cache.

[0070] The structural fingerprint storage module 330 obtains the equivalent cross-sectional area function through interpolation. The equivalent cross-sectional area function can be expressed as:

[0071] Piecewise linear interpolation is preferred for interpolation processing. Assume the current real-time liquid level in the tank. Representative liquid levels located within the real-time liquid level ranges of the two covered tanks and Between, and The corresponding average dynamic equivalent cross-sectional areas are respectively and The equivalent cross-sectional area function can be determined according to the following formula:

[0072]

[0073] in, Represents the equivalent cross-sectional area function. This represents the real-time liquid level variable in the water tank used for querying. and These represent the representative liquid levels of two adjacent covered water tank real-time liquid level intervals, respectively. and These represent the average dynamic equivalent cross-sectional area of ​​the corresponding real-time liquid level range of the water tank. When using this piecewise linear interpolation, the rate of structural change is... and The distance can be determined using the following formula:

[0074]

[0075] in, This indicates the rate of structural change. If the current real-time liquid level of the water tank is lower than the lowest covered real-time liquid level range or higher than the highest covered real-time liquid level range, the structural fingerprint storage module 330 does not extrapolate, but instead outputs the state that the liquid level-dynamic equivalent cross-sectional area structural fingerprint has not yet covered the real-time liquid level range of the water tank where the current real-time liquid level is located.

[0076]

[0077] in, Represents the equivalent cross-sectional area function. This represents the real-time liquid level variable in the water tank used for querying. This indicates the interpolation process performed based on the valid sample set. The interpolation process can employ piecewise linear interpolation or an existing interpolation function of the control device 300. This interpolation process is only used to obtain a queryable equivalent cross-sectional area function between adjacent valid samples.

[0078] The structural fingerprint storage module 330 also obtains the structural change rate based on the equivalent cross-sectional area function. The structural change rate can be expressed as:

[0079]

[0080] in, Indicates the rate of structural change. Represents the equivalent cross-sectional area function. This represents the real-time liquid level variable of the water tank. If the equivalent cross-sectional area function uses piecewise linear interpolation, the rate of change of the structure can be obtained from the slope of the equivalent cross-sectional area function within the real-time liquid level interval of adjacent water tanks; if the equivalent cross-sectional area function uses the existing interpolation function of the control device 300, the rate of change of the structure can be obtained from the difference slope of that interpolation function.

[0081] The liquid level-dynamic equivalent cross-sectional area structural fingerprint is composed of the equivalent cross-sectional area function and the structural change rate, and can be expressed as:

[0082]

[0083] in, This represents a liquid level-dynamic equivalent cross-sectional area structure fingerprint. Represents the equivalent cross-sectional area function. This represents the rate of structural change. The equivalent cross-sectional area function reflects the change in water volume corresponding to a unit change in real-time water level at different tank levels, while the rate of structural change reflects how quickly the equivalent cross-sectional area function changes with the real-time water level. Both are used together for subsequent volume deviation conversion and determination of the structural adaptive frequency limit value.

[0084] When the liquid level-dynamic equivalent cross-sectional area structural fingerprint has not yet covered the real-time liquid level range of the current tank, the structural fingerprint storage module 330 outputs the current available coverage status to the volume deviation conversion module 340. If there is a valid sample closest to the liquid level value of the current tank, the volume deviation conversion module 340 can use the equivalent cross-sectional area function corresponding to the valid sample to perform volume deviation conversion. If there is no valid sample closest to the liquid level value of the current tank, the control device 300 reverts to the fixed liquid level control mode. This revert strategy is used to ensure that the single-tank multi-well water collection system can still maintain basic liquid level control when the liquid level-dynamic equivalent cross-sectional area structural fingerprint has not been fully formed.

[0085] The selection rule for the most recent valid sample is as follows: First, calculate the absolute difference between the current real-time liquid level of the tank and the representative liquid level of each covered tank real-time liquid level interval, and select the covered tank real-time liquid level interval with the smallest absolute difference. When the absolute differences between two covered tank real-time liquid level intervals and the current tank real-time liquid level are the same, select the covered tank real-time liquid level interval with the later update time. When the update times are also the same, select the lower tank real-time liquid level interval. The average dynamic equivalent cross-sectional area corresponding to the selected covered tank real-time liquid level interval is used as the equivalent cross-sectional area function corresponding to the most recent valid sample for volume deviation transformation. This selection rule is only used when the liquid level-dynamic equivalent cross-sectional area structural fingerprint has not yet covered the real-time liquid level interval of the tank where the current tank real-time liquid level is located.

[0086] When no valid sample is found that is closest to the current real-time liquid level of the tank, the fixed liquid level control mode operates according to the existing liquid level difference control logic of the control device 300. The fixed liquid level control mode uses the liquid level difference between the current real-time liquid level of the tank and the target liquid level as the feedback control quantity. It uses existing fixed proportional-integral parameters, fixed proportional-integral-derivative parameters, or fixed frequency changes to determine the well pump group start / stop commands and frequency conversion commands. Meanwhile, the safety interlock module 370 continues to maintain the highest priority. During the operation of the fixed liquid level control mode, the structural sample calculation module 320 can still generate valid samples when the real-time liquid level of the tank, the total inflow rate, and the outflow rate at the rear of the tank meet the valid sample conditions. Once the liquid level-dynamic equivalent cross-sectional area structural fingerprint covers the real-time liquid level range of the tank, the control device 300 resumes volume deviation conversion.

[0087] The volume deviation conversion module 340 converts the difference between the current real-time liquid level in the tank and the target liquid level into a volume deviation based on the liquid level-dynamic equivalent cross-sectional area structural fingerprint. The target liquid level is the liquid level that the control device 300 wants the water collection tank 100 to reach or maintain. The current real-time liquid level in the tank is provided by the tank level sensor 110 in the current control cycle. The volume deviation is used to characterize the difference in the volume of water stored between the current real-time liquid level in the tank and the target liquid level, rather than simply characterizing the difference in the numerical value of the real-time liquid level in the tank.

[0088] Volume deviation can be determined using the following formula:

[0089]

[0090] in, Indicates the first Volume deviation per control cycle Indicates the first Volume deviation per control cycle This indicates the current real-time liquid level in the water tank. Indicates the target liquid level. Indicates the integral variable The query returns the equivalent cross-sectional area function. If the current real-time water level in the tank is lower than the target level, the integral result is positive, and the volume deviation represents the increase in water storage volume required; if the current real-time water level in the tank is higher than the target level, the integral result is negative, and the volume deviation represents the decrease in water storage volume required.

[0091] In the control device 300, the volume deviation conversion module 340 can implement the above integration using a piecewise accumulation method. If the equivalent cross-sectional area function is stored in the form of real-time liquid level intervals of the water tank, the volume deviation conversion module 340 starts from the real-time liquid level interval of the current water tank and reads the equivalent cross-sectional area function segment by segment along the direction of the target liquid level, and multiplies the equivalent cross-sectional area function of each real-time liquid level interval of the water tank with the width of the corresponding real-time liquid level interval and then accumulates them. If the current real-time liquid level of the water tank and the target liquid level are located in the same real-time liquid level interval of the water tank, the volume deviation conversion module 340 only calculates a portion of the interval within that real-time liquid level interval.

[0092] The purpose of using volume deviation instead of directly using liquid level difference is to give the feedback control quantity received by the structural adaptive control module 350 the meaning of water storage volume. When the equivalent cross-sectional area function of the water collection tank 100 in a certain real-time liquid level range of a certain tank is small, a small volume deviation can correspond to a significant change in the real-time liquid level of the tank, and the structural adaptive control module 350 does not need to increase the total water intake demand excessively; when the equivalent cross-sectional area function of the water collection tank 100 in another real-time liquid level range of a certain tank is large, the same liquid level difference corresponds to a larger volume deviation, and the structural adaptive control module 350 can increase the total water intake demand accordingly.

[0093] When the liquid level-dynamic equivalent cross-sectional area structure fingerprint has not yet covered the real-time liquid level range of the current tank, the volume deviation conversion module 340 first uses the equivalent cross-sectional area function corresponding to the nearest valid sample to the current real-time liquid level value to perform volume deviation conversion. This process allows the control device 300 to still use existing valid samples for approximate control during the gradual formation stage of the liquid level-dynamic equivalent cross-sectional area structure fingerprint. When there is no nearest valid sample to the current real-time liquid level value, the volume deviation conversion module 340 does not output the volume deviation based on the liquid level-dynamic equivalent cross-sectional area structure fingerprint, and the control device 300 reverts to the fixed liquid level control mode.

[0094] The structural adaptive control module 350 determines the total inlet water demand, the structural adaptive frequency limit, and the frequency conversion command based on the volume deviation, the water flow rate at the rear end of the tank, the equivalent cross-sectional area function, and the structural change rate. The structural adaptive control module 350 receives the volume deviation output from the volume deviation conversion module 340, the water flow rate at the rear end of the tank output from the basic signal acquisition module 310, and the equivalent cross-sectional area function and structural change rate output from the structural fingerprint storage module 330. The total inlet water demand output by the structural adaptive control module 350 is sent to the pump group sequence control module 360, and the frequency conversion command is sent to the frequency converter 240.

[0095] The structural adaptive control module 350 can obtain the inlet water regulation amount by using volume deviation as feedback control quantity. The inlet water regulation amount can be calculated using a conventional proportional-integral structure.

[0096]

[0097] in, Indicates the first Inlet water adjustment amount per control cycle The proportionality coefficient representing the volume deviation, The integral coefficient representing the volume deviation. Indicates the first Volume deviation per control cycle This indicates a fixed sampling period. The proportional and integral coefficients can be determined using existing control system tuning methods. Integral limiting, integral freezing, and output limiting can be handled using standard procedures in existing PLC control programs.

[0098] It should be noted that the proportionality coefficient The dimension is flow rate divided by volume, and the integral coefficient is... The dimensions are flow rate divided by volume and then by time. During tuning, first determine the maximum volume deviation. and expected recovery time The maximum volume deviation is the maximum permissible absolute value of the volume deviation within the normal liquid level range, and its dimension is volume; the expected recovery time is the time allowed for the control device 300 to restore the real-time liquid level of the tank from the lower or upper limit of normal to near the target liquid level, and its dimension is time. The proportional coefficient can be taken as... The integral coefficient can be taken as... During the initial tuning, the expected recovery time can be taken as... to And it is corrected according to the stabilization adjustment time of the existing fixed liquid level control mode.

[0099] The tuning steps for the proportional and integral coefficients are as follows: First, in fixed-level control mode, record the adjustment time required for the real-time water tank level to recover from the normal lower limit to the target level, the total inflow rate, and the outflow rate at the rear end of the water tank; then, calculate the volume deviation change corresponding to this adjustment process based on the established equivalent cross-sectional area function; next, select the proportional coefficient according to the principle of not exceeding the maximum total inflow rate, and gradually increase the integral coefficient without causing continuous oscillation of the real-time water tank level; finally, the qualified tuning standard is that the real-time water tank level reaches near the target level and the well pump group start / stop commands do not frequently switch. If high-high level, low-low level, overcurrent, overtemperature, overpressure, dry running, communication interruption, or inverter failure occurs during the tuning process, the tuning is stopped and the safety interlock module 370 overwrites the normal adjustment result.

[0100] The adaptive control module 350 uses the water flow rate at the rear end of the water tank as a balancing benchmark, and correlates the inlet water adjustment with the water flow rate at the rear end of the water tank to form the total inlet water demand. The unlimited flow rate demand can be obtained first:

[0101]

[0102] in, Indicates the first Unlimited traffic demand during a control cycle Indicates the first The water flow rate at the back end of the water tank during each control cycle Indicates the first The inlet water adjustment amount for each control cycle. When the outlet water flow at the rear end of the water tank is used as the balancing benchmark, if the volume deviation is zero, the total inlet water demand is mainly used to balance the outlet water flow at the rear end of the water tank; if the volume deviation is positive, the total inlet water demand increases based on the outlet water flow at the rear end of the water tank; if the volume deviation is negative, the total inlet water demand decreases based on the outlet water flow at the rear end of the water tank.

[0103] Total water intake demand can be obtained through limiting:

[0104]

[0105] in, Indicates the first Total water inflow demand for each control cycle Indicates the first Unlimited traffic demand during a control cycle Indicates the first The maximum total inflow rate allowed for the well pump unit 210 in the current available state during each control cycle. This represents the limiting function. This limiting is used to ensure that the total water demand is not less than zero and does not exceed the current achievable water supply capacity of the well pump group 210.

[0106] Maximum total inflow rate The dimension of is flow rate, and it is updated according to the well pump availability status in each control cycle. If the ... If the well pump is in usable condition, then the rated flow rate of the single well corresponding to that pump will be included in the maximum total inflow rate; if the... If a well pump malfunctions, fails to meet the minimum downtime requirement, is removed from the available collection by safety interlock module 370, or is in a manually disabled state, the rated flow rate of the corresponding well will not be included in the maximum total inflow rate. The maximum total inflow rate can be expressed as:

[0107]

[0108] in, Indicates the first The maximum total inflow rate for each control cycle Indicates the first The set of available well pumps corresponding to the well pump availability status of each control cycle. Indicates the first The rated flow rate of a single well in the tandem pump. When the available well pump set is empty, the maximum total inflow rate is zero, and the pump set sequence control module 360 ​​does not output start / stop commands for the pump set to be put into operation.

[0109] The structural adaptive control module 350 determines the structural adaptive frequency limit based on the degree of real-time liquid level change in the tank caused by a unit of water inflow, characterized by the equivalent cross-sectional area function, and the degree of capacity scale change, characterized by the structural change rate. When the equivalent cross-sectional area function is small, the degree of real-time liquid level change in the tank caused by a unit of water inflow increases, and the structural adaptive control module 350 reduces the structural adaptive frequency limit. When the absolute value of the structural change rate is large, the degree of capacity scale change increases, and the structural adaptive control module 350 reduces the structural adaptive frequency limit. Through this process, the allowable variation of the frequency conversion command relative to the previous control cycle is constrained by the actual capacity structure of the water collection tank 100.

[0110] The adaptive frequency limiting value for the structure can be determined as follows:

[0111]

[0112] in, Indicates the first Structural change suppression coefficient for each control cycle The weighting coefficient represents the rate of change of structure. This represents the rate of structural change corresponding to the current real-time liquid level in the tank. The larger the absolute value of the rate of structural change, the greater the structural change inhibition coefficient.

[0113] Structural change rate weighting coefficient The dimension of is the reciprocal of the rate of structural change, making It is a dimensionless quantity. In specific implementation, a reference value for the rate of structural change can be selected within the real-time liquid level range of the water tank covered by the liquid level-dynamic equivalent cross-sectional area structural fingerprint. The reference value for the structural change rate can be the maximum absolute value of the structural change rate within the real-time liquid level range of the covered water tank or a representative value confirmed by the engineers, and the weighting coefficient of the structural change rate should be determined according to the following formula:

[0114]

[0115] in, The weighting coefficient represents the rate of change of structure. Indicates the dimensionless inhibition ratio. This represents a reference value for the rate of structural change. This represents the lower limit of the structural change rate reference. The dimensions of the lower limit of the structural change rate reference are the same as the structural change rate, and its value is derived from the accuracy of the equivalent cross-sectional area function calculation or the numerical resolution of the control device (300). When When, the weighting coefficient of the structural change rate is taken To avoid division by zero when the structural change rate reference value is zero or close to zero; when At that time, the weighting coefficient of the rate of structural change is according to Calculation. The dimensionless suppression ratio can be taken as... to A smaller value is used when it is desired that the structural change rate has a weaker impact on the adaptive frequency limiting value, and a larger value is used when it is desired that the structural change rate has a stronger impact on the adaptive frequency limiting value. If a reference value for the structural change rate is not yet available, the weighting coefficient for the structural change rate is temporarily set to... The control device 300 determines the adaptive frequency limit value of the structure solely based on the equivalent cross-sectional area function.

[0116]

[0117] in, Indicates the first The frequency variation range without amplitude limitation in each control cycle The coefficient representing the equivalent cross-sectional area function converted to the frequency range. This represents the equivalent cross-sectional area function corresponding to the current real-time liquid level in the water tank. This represents the structural change suppression coefficient. The smaller the equivalent cross-sectional area function, the smaller the unlimited frequency variation range; the larger the structural change suppression coefficient, the smaller the unlimited frequency variation range.

[0118] coefficient The dimension of this is frequency divided by area, making It has frequency dimensions. In practical implementation, a reference value for the equivalent cross-sectional area function can be selected. and reference frequency variation range And determine the coefficients according to the following formula. :

[0119]

[0120] in, The coefficient representing the equivalent cross-sectional area function converted to the frequency range. Indicates the range of reference frequency variation. This represents the reference value of the equivalent cross-sectional area function. The reference value of the equivalent cross-sectional area function can be taken as the median or arithmetic mean of the average dynamic equivalent cross-sectional area within the real-time liquid level range of the water tank covered by the liquid level-dynamic equivalent cross-sectional area structural fingerprint. The reference frequency variation range can be taken as the single-cycle fixed frequency variation in the existing fixed liquid level control mode, and it shall not exceed the single-cycle frequency variation range allowed by the frequency converter 240.

[0121]

[0122] in, Indicates the first The structure-adaptive frequency limiting value for each control cycle Indicates the minimum frequency variation range. This indicates the maximum frequency variation range. The minimum and maximum frequency variation ranges can follow the conventional engineering limitations of the frequency converter 240 and the well pump set 210.

[0123] Minimum frequency variation range The unit of measurement is frequency, and the value is not less than the frequency resolution of the inverter (240 Hz); maximum frequency variation range The dimension of the value is frequency, and its value is no greater than the single-cycle fixed frequency change in the existing fixed liquid level control mode, nor greater than the single-cycle frequency change range allowed by the inverter 240. When the inverter 240 experiences a fault or communication interruption, the structural adaptive control module 350 stops updating the inverter frequency command, and the safety interlock module 370 directly overrides the inverter frequency command. When the control device 300 reverts to the fixed liquid level control mode, the structural adaptive frequency limit value does not participate in the normal liquid level regulation. It will re-participate in the inverter frequency command limit after the liquid level-dynamic equivalent cross-sectional area structural fingerprint is restored to validity.

[0124] The variable frequency command can be obtained by limiting the difference between the target frequency and the variable frequency command of the previous control cycle by a structural adaptive frequency limit. The target frequency can be obtained from the existing frequency-flow correspondence of the variable frequency pump, the rated flow ratio distribution relationship, or the existing control program. This target frequency is not a new inventive feature of this embodiment. The key limitation of the structural adaptive control module 350 is to determine the structural adaptive frequency limit using the equivalent cross-sectional area function and the structural change rate.

[0125]

[0126] in, Indicates the first The frequency variation of each control cycle Indicates the first The target frequency for each control cycle This indicates the frequency conversion command of the previous control cycle.

[0127]

[0128] in, Indicates the first The allowable negative frequency variation boundary for each control cycle. Indicates the first The structure-adaptive frequency limiting value for each control cycle.

[0129]

[0130] in, Indicates the first The allowable positive frequency variation boundary for each control cycle. Indicates the first The structure-adaptive frequency limiting value for each control cycle.

[0131]

[0132] in, This indicates the difference in frequency variation after being limited by the structural adaptive frequency limiting value. Indicates differences in frequency variation. Indicates the boundary of negative frequency change. This indicates the boundary of the positive frequency change.

[0133]

[0134] in, Indicates the first The intermediate frequency command of each control cycle This indicates the frequency conversion command of the previous control cycle. This indicates the difference in frequency change after being limited by the structural adaptive frequency limiting value.

[0135]

[0136] in, Indicates the first Frequency conversion command for each control cycle Indicates the first The intermediate frequency command of each control cycle This indicates the minimum allowable frequency for inverter 240. This indicates the maximum allowed frequency of inverter 240. Through the above processing, the frequency conversion command satisfies both the upper and lower frequency limits of inverter 240 and the limitation of the variation amplitude of adjacent control cycles by the structural adaptive frequency limit value.

[0137] minimum frequency and maximum frequency All values ​​are in the dimension of frequency, and their values ​​are derived from the allowable operating frequency range of the frequency converter 240, the allowable operating frequency range of the well pump group 210, and existing protection parameters on site. If the upper and lower limits of the frequency fed back by the frequency converter 240 change, the structural adaptive control module 350 updates the minimum and maximum frequencies in the next control cycle. If the safety interlock module 370 determines that the frequency converter is faulty, overcurrent, overtemperature, or running dry, the structural adaptive control module 350 will no longer drive the well pump group 210 with the ordinary frequency command after the minimum and maximum frequency limits are applied, and the safety interlock module 370 will directly output the overlay result.

[0138] The pump sequence control module 360 ​​determines the start / stop commands for the well pumps based on the total water intake demand output by the structural adaptive control module 350. The pump sequence control module 360 ​​can determine the number of operating well pumps and the pump group rotation sequence according to the total water intake demand, the rated flow rate of a single well, the availability status of the well pumps, and the cumulative operating time. This part adopts the conventional pump sequence control logic in a single-tank multi-well water collection system.

[0139] The number of operating well pumps can be determined using the following formula:

[0140]

[0141] in, This indicates the preliminary number of operating well pumps determined based on the total water intake demand. Indicates the first Total water inflow demand for each control cycle Indicates the rated flow rate of a single well. This indicates rounding up. This formula is used to estimate the number of well pumps that need to be put into operation based on total water intake demand.

[0142] The number of operating well pumps corresponding to the actual well pump group start / stop command can be determined according to the following formula:

[0143]

[0144] in, Indicates the first The number of operating well pumps activated by the control cycle command. This indicates the number of available well pumps corresponding to the well pump availability status. This indicates the initially determined number of operating well pumps. This formula is used to ensure that well pump start-up and shutdown commands do not require the operation of more well pumps than the number allowed for availability, nor do they require the operation of a negative number of well pumps.

[0145] After determining the number of operating well pumps, the pump sequence control module 360 ​​selects specific well pumps based on the cumulative operating time and the well pump group rotation sequence. If the first well pump 211, the second well pump 212, and the third well pump 213 are all available, the pump sequence control module 360 ​​can prioritize selecting the well pump with the shorter cumulative operating time to balance the operating load of the well pump group 210. If a well pump is in a faulty state or has not met the minimum downtime, the pump sequence control module 360 ​​removes that well pump from the available set and re-determines the well pump group start / stop command from the remaining well pumps.

[0146] The start / stop command for the well pump unit is applied to the well pump unit 210 via contactor 250, and the frequency conversion command is applied to the well pump unit 210 via frequency converter 240. For multiple frequency conversion well pumps, the control device 300 can allocate them according to the rated flow ratio or the principle of the same frequency. The liquid level-dynamic equivalent cross-sectional area structural fingerprint is used to determine the total water intake demand and the structural adaptive frequency limit value.

[0147] The safety interlock module 370 is used to override the well pump set start / stop command and the frequency converter command when the safety interlock is triggered. Safety interlock triggers include high-high liquid level, low-low liquid level, overcurrent, overtemperature, overpressure, dry running, communication interruption, or frequency converter failure. These safety interlock trigger states can be jointly provided by the water tank level sensor 110, float switch 140, pressure sensor 150, motor protection signal input 260, communication status input 270, frequency converter feedback 240, and well pump set feedback 210.

[0148] When a high liquid level occurs, the safety interlock module 370 directly overrides the control result of increasing total water intake, which can stop some or all well pumps, or prohibit further increases in the frequency converter. When a low liquid level occurs, the safety interlock module 370 can restrict pumping from the rear of the water tank or enter a protection state according to the field protection logic. High and low liquid levels are hardware protection and control protections with fixed liquid level boundaries, and are not covered by the liquid level-dynamic equivalent cross-sectional area structure fingerprint.

[0149] In the event of overcurrent, overtemperature, or dry running, the motor protection signal input 260 sends the relevant status to the safety interlock module 370. The safety interlock module 370 can deactivate the corresponding well pump from its usable state and cause the pump group sequence control module 360 ​​to recalculate the total available water supply capacity. In the event of overpressure, the pressure sensor 150 sends the overpressure status to the safety interlock module 370, which can limit the well pump group 210 from further increasing its output. In the event of a communication interruption, the communication status input 270 sends the communication interruption status to the safety interlock module 370, which can override the well pump group start / stop commands and frequency conversion commands, and pause the update of the liquid level-dynamic equivalent cross-sectional area structure fingerprint.

[0150] The safety interlock module 370 is also used to handle inverter faults. When the inverter 240 fails, the frequency conversion command output by the structure adaptive control module 350 cannot be executed normally. The safety interlock module 370 directly overrides this frequency conversion command and uses the inverter fault status to determine the availability of the well pump group 210. The override priority of the safety interlock module 370 is higher than the normal adjustment results of the structure adaptive control module 350 and the pump group sequence control module 360.

[0151] When the real-time water level, total inflow rate, or outflow rate at the rear of the water tank fails the signal validity check, the control device 300 suspends updating the water level-dynamic equivalent cross-sectional area structure fingerprint. Suspending the update does not equate to stopping the safe operation of the single-tank multi-well water collection system; the control device 300 can revert to the fixed water level control mode and continue to execute safety interlocks for high-high water level, low-low water level, overcurrent, overtemperature, overpressure, dry running, communication interruption, or inverter failure.

[0152] For example, at the start of a complete control cycle, the basic signal acquisition module 310 first reads the real-time water level output by the water tank level sensor 110, reads the flow rates of each well output by the first well flow meter 221, the second well flow meter 222, and the third well flow meter 223, reads the water tank rear outlet flow rate output by the water tank rear outlet flow meter 130, and reads the device status corresponding to the float switch 140, pressure sensor 150, motor protection signal input 260, and communication status input 270. The basic signal acquisition module 310 performs range status checks, communication status checks, and timestamp consistency checks on the real-time water level, total inlet flow rate, and water tank rear outlet flow rate.

[0153] Subsequently, the basic signal acquisition module 310 sums the flow rates of each well to obtain the total influent flow rate, and sends the real-time water tank level, total influent flow rate, and water tank outlet flow rate to the structural sample calculation module 320. The structural sample calculation module 320 reads the real-time water tank level from the previous control cycle, obtains the real-time water tank level change at adjacent sampling times, and calculates the dynamic equivalent cross-sectional area sample based on the total influent flow rate, water tank outlet flow rate, and fixed sampling cycle. The structural sample calculation module 320 determines whether the direction of the real-time water tank level change is consistent with the net flow direction determined by the difference between the total influent flow rate and the water tank outlet flow rate, whether the real-time water tank level change is within the resolvable range of the water tank level sensor 110, and whether the real-time water tank level, total influent flow rate, and water tank outlet flow rate pass the signal validity check.

[0154] When all the above conditions are met, the structural sample calculation module 320 uses the dynamic equivalent cross-sectional area sample as a valid sample and sends the valid sample to the structural fingerprint storage module 330. The structural fingerprint storage module 330 sorts the valid samples according to the real-time liquid level of the water tank, averages the valid samples in the same or adjacent real-time liquid level ranges of the water tank, and obtains the equivalent cross-sectional area function and structural change rate through interpolation. The volume deviation conversion module 340 reads the current real-time liquid level of the water tank, the target liquid level, and the equivalent cross-sectional area function, and converts the liquid level difference between the current real-time liquid level and the target liquid level into a volume deviation.

[0155] Next, the structural adaptive control module 350 uses the volume deviation as feedback control quantity to obtain the inlet water adjustment quantity, and uses the outflow rate at the rear of the water tank as a balance benchmark to form the total inlet water demand. The structural adaptive control module 350 also determines the structural adaptive frequency limit value based on the equivalent cross-sectional area function corresponding to the current real-time liquid level in the water tank and the structural change rate, and uses this structural adaptive frequency limit value to limit the allowable variation of the frequency conversion command relative to the previous control cycle. The pump group sequence control module 360 ​​determines the number of operating well pumps and the well pump group rotation sequence based on the total inlet water demand, the rated flow rate of a single well, the availability status of the well pumps, and the cumulative operating time, and generates well pump group start / stop commands.

[0156] Finally, the control device 300 outputs the well pump group start / stop command to the contactor 250 and the frequency conversion command to the frequency converter 240. The safety interlock module 370 maintains higher priority throughout the entire control cycle; in the event of high-high liquid level, low-low liquid level, overcurrent, overtemperature, overpressure, dry running, communication interruption, or frequency converter failure, the safety interlock module 370 overrides the well pump group start / stop command and the frequency conversion command. The control device 300 records the real-time liquid level of the water tank, the flow rate of each well, the outflow rate of the water tank's rear end, the total inflow rate, the effective sample, the equivalent cross-sectional area function, the structural change rate, the volume deviation, the total inflow demand, the structural adaptive frequency limit value, the well pump group start / stop command, and the frequency conversion command, and then proceeds to the next control cycle.

[0157] As an optional implementation, the first well pump 211, the second well pump 212, and the third well pump 213 are all in a usable state. The water tank level sensor 110, the flow meters 220 of each well, and the water tank rear outlet flow meter 130 have all passed signal validity checks, and the real-time water tank level is within the normal range. The basic signal acquisition module 310 continuously outputs the real-time water tank level, the total inflow rate, and the water tank rear outlet flow rate. The structural sample calculation module 320 forms a valid sample when the direction of change in the real-time water tank level is consistent with the direction of net flow determined by the difference between the total inflow rate and the water tank rear outlet flow rate. The structural fingerprint storage module 330 gradually supplements the level-dynamic equivalent cross-sectional area structural fingerprint. At this time, the volume deviation conversion module 340 converts the level difference into a volume deviation according to the equivalent cross-sectional area function, and the structural adaptive control module 350 determines the total inflow demand based on the volume deviation and the water tank rear outlet flow rate, causing the water collection tank 100 to move closer to the target level.

[0158] As an alternative implementation, with a smaller equivalent cross-sectional area function, the water collection tank 100 may be located in a conical bottom region, a circular arc transition region, or a region where internal fixed components significantly occupy the real-time liquid level range. The equivalent cross-sectional area function output by the structural fingerprint storage module 330 indicates an increased degree of real-time liquid level change in the tank caused by a unit of water inflow. Accordingly, the structural adaptive control module 350 reduces the structural adaptive frequency limit value, thereby reducing the allowable variation of the frequency conversion command relative to the previous control cycle. Through this processing, the frequency converter 240 will not generate excessive frequency changes within a control cycle when driving the well pump group 210, which helps to reduce liquid level overshoot and repeated adjustments.

[0159] As an optional implementation, a larger equivalent cross-sectional area function results in a larger change in water volume corresponding to the current real-time liquid level range of the water collection tank 100. The same real-time liquid level change in the same tank corresponds to a larger volume deviation. As the volume deviation output by the volume deviation conversion module 340 increases, the structure adaptive control module 350 generates a larger total water intake demand based on the water flow rate at the rear of the tank. The pump sequence control module 360 ​​activates the corresponding number of well pumps according to the total water intake demand, and the frequency converter 240 outputs a frequency command constrained by the structure adaptive frequency limit, thereby increasing the speed of recovery from a low liquid level to the target liquid level.

[0160] As an optional implementation, the structural change rate is relatively large, and the equivalent cross-sectional area function changes rapidly within the real-time liquid level range of adjacent tanks. The increased degree of capacity scale change represented by the structural change rate leads the structural adaptive control module 350 to reduce the structural adaptive frequency limit. This processing is suitable for controlling the real-time liquid level of the tank when it crosses the cone bottom region, arc transition region, step region, or the influence zone of internal fixed components. After reducing the structural adaptive frequency limit, the change in the frequency conversion command is smoother, and the well pump group 210 is less likely to experience real-time liquid level overshoot due to excessive fixed frequency changes when passing through the real-time liquid level range of the tank where the capacity scale changes rapidly.

[0161] In situations where the liquid level-dynamic equivalent cross-sectional area structural fingerprint has not yet covered the real-time liquid level range of the current tank, the structural fingerprint storage module 330 first determines whether there is a valid sample that is closest to the current tank's real-time liquid level value. If such a valid sample exists, the volume deviation conversion module 340 uses the equivalent cross-sectional area function corresponding to the valid sample to perform volume deviation conversion. If no valid sample exists, the control device 300 reverts to the fixed liquid level control mode and continues to wait for a subsequent control cycle to generate a valid sample. This situation typically occurs when the system is first put into operation, the liquid level-dynamic equivalent cross-sectional area structural fingerprint storage area is initialized to be empty, or the system has not entered a certain tank's real-time liquid level range for a long period of time.

[0162] As an optional implementation, if the water flow meter 130 at the rear of the water tank malfunctions, preventing the water flow rate from being directly collected by the on-site flow meter, the structural sample calculation module 320 will pause updating the liquid level-dynamic equivalent cross-sectional area structural fingerprint. This is because, without the water flow rate at the rear of the water tank, relying solely on the real-time liquid level and total inflow rate cannot uniquely determine the correspondence between the change in water volume within the collection tank 100 and the change in the real-time liquid level. In this case, the control device 300 will revert to the fixed liquid level control mode and continue executing the overlay control of the safety interlock module 370.

[0163] As an optional implementation, when the well pump is first started or stopped, after the contactor 250 outputs the start / stop command for the well pump group, there may be a short-term transition in the flow rate in the well pump group 210 and the inlet manifold 230. This short-term transition will affect the synchronization relationship between the total inlet flow rate and the real-time liquid level change in the water tank. The structural sample calculation module 320 pauses updating the liquid level-dynamic equivalent cross-sectional area structural fingerprint when the well pump is first started or stopped, and resumes valid sample judgment after the operating status of the well pump group 210 stabilizes.

[0164] As an optional implementation, if the safety interlock is triggered by the float switch 140 (high / high liquid level or low / low liquid level), the motor protection signal input 260 (overcurrent, overtemperature, or dry running), the pressure sensor 150 (overpressure), the communication status input 270 (communication interruption), or the frequency converter 240 (frequency converter fault), then the safety interlock module 370 directly overrides the well pump start / stop command and the frequency conversion command. In this case, even if the volume deviation conversion module 340 and the structural adaptive control module 350 can still calculate the normal adjustment result, the normal adjustment result cannot override the output of the safety interlock module 370.

[0165] The water tank level sensor 110 can be an immersion level gauge, radar level gauge, ultrasonic level gauge, or other industrial level sensor, as long as it can provide the control device 300 with the real-time water tank level. The flow meters 220 for each well and the water tank outlet flow meter 130 can be electromagnetic flow meters, ultrasonic flow meters, or other existing flow meters, as long as they can provide the flow rate of each well and the water tank outlet flow rate respectively. The frequency converter 240 and contactor 250 can be existing drive and start / stop actuators in a single-tank multi-well water collection system. The specific devices selected above are for implementing this embodiment, and there is no limitation on the specific brand or model within the scope of protection.

[0166] The software program of the control device 300 can be implemented using a periodic task approach. At the start of a periodic task, the basic signal acquisition module 310 is executed, followed by the structural sample calculation module 320, the structural fingerprint storage module 330, the volume deviation conversion module 340, the structural adaptive control module 350, the pump group sequence control module 360, and the safety interlock module 370. The safety interlock module 370 can uniformly override the output at the end of the periodic task, or it can override the output in real time during the periodic task in the form of interruption, fast task, or high-priority logic. Regardless of the software structure used, the safety interlock module 370 directly overrides the well pump group start / stop command and frequency conversion command when the safety interlock is triggered.

[0167] A computer-readable storage medium may store a computer program for executing this embodiment. When the computer program is executed by the control device 300, the control device 300 performs the following control process: periodically directly acquiring or receiving real-time water tank level, well flow rate, and water tank outlet flow rate directly acquired by field sensors, and obtaining the total inflow flow rate based on the well flow rate; determining dynamic equivalent cross-sectional area samples and valid samples based on the total inflow flow rate, water tank outlet flow rate, and real-time water tank level changes at adjacent sampling times; generating a level-dynamic equivalent cross-sectional area structural fingerprint based on the valid samples; converting the level difference between the current real-time water tank level and the target water level into a volume deviation based on the level-dynamic equivalent cross-sectional area structural fingerprint; determining the total inflow demand based on the volume deviation and water tank outlet flow rate; determining well pump group start / stop commands based on the total inflow demand; determining the structural adaptive frequency limit value based on the equivalent cross-sectional area function and structural change rate, and limiting the allowable variation range of the frequency conversion command relative to the previous control cycle.

[0168] The computer program can be stored in the form of a programmable logic controller program, an industrial controller program, an embedded control program, or a host control software program that works in conjunction with a field controller. The computer-readable storage medium can be non-volatile memory, a memory card, a solid-state memory, or other conventional media capable of storing programs within the control device 300.

[0169] The embodiments of this example have been described above. However, this example is not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms based on the guidance of this example, and all of them are within the protection scope of this example.

Claims

1. A control method for a single-tank multi-well water collection system, applicable to a single-tank multi-well water collection system having a water collection tank, a well pump set, and a control device, characterized in that, include: The control device periodically collects or receives the real-time liquid level of the water tank, the flow rate of each well, and the outflow rate of the water tank from the rear end, which are directly collected by the field sensors, and obtains the total inflow rate based on the flow rate of each well. Based on the total influent flow rate, the outfluent flow rate at the rear end of the water tank, and the real-time liquid level change of the water tank at adjacent sampling times, a dynamic equivalent cross-sectional area sample is determined. The dynamic equivalent cross-sectional area sample is the ratio of the product of the difference between the total influent flow rate and the outfluent flow rate at the rear end of the water tank multiplied by the sampling time interval between adjacent sampling times, to the difference in the real-time liquid level of the water tank at adjacent sampling times. The dynamic equivalent cross-sectional area sample is considered a valid sample when the direction of the real-time liquid level change of the water tank is consistent with the net flow direction determined by the difference between the total influent flow rate and the outfluent flow rate at the rear end of the water tank, the real-time liquid level change of the water tank is within the resolvable range of the water tank level sensor, and the real-time liquid level of the water tank, the total influent flow rate, and the outfluent flow rate at the rear end of the water tank pass the signal validity check. Based on the valid samples, a liquid level-dynamic equivalent cross-sectional area structural fingerprint containing an equivalent cross-sectional area function and a structural change rate is generated, wherein the equivalent cross-sectional area function is a function with the real-time liquid level of the water tank as the independent variable and the dynamic equivalent cross-sectional area as the function value, and the structural change rate is the rate of change of the equivalent cross-sectional area function with the real-time liquid level of the water tank. Based on the liquid level-dynamic equivalent cross-sectional area structure fingerprint, the liquid level difference between the current real-time liquid level in the water tank and the target liquid level is converted into a volume deviation; The total water intake demand is determined based on the volume deviation and the water flow rate at the rear end of the water tank. The start / stop command of the well pump group is determined based on the total water intake demand. The adaptive frequency limit value of the structure is determined based on the equivalent cross-sectional area function and the structural change rate. The adaptive frequency limit value of the structure is used to limit the allowable change range of the frequency conversion command relative to the previous control cycle.

2. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, The signal validity check includes range status check, communication status check, and timestamp consistency check for the real-time liquid level of the water tank, the total inflow rate, and the outflow rate at the rear end of the water tank.

3. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, Generating the liquid level-dynamic equivalent cross-sectional area structural fingerprint includes: sorting the valid samples according to the real-time liquid level of the water tank; averaging the valid samples within the same real-time liquid level range of the water tank to obtain the average dynamic equivalent cross-sectional area of ​​each covered real-time liquid level range; performing piecewise linear interpolation on the average dynamic equivalent cross-sectional area of ​​adjacent covered real-time liquid level ranges to obtain the equivalent cross-sectional area function with the real-time liquid level of the water tank as the independent variable and the dynamic equivalent cross-sectional area as the function value; and determining the slope of the equivalent cross-sectional area function between adjacent covered real-time liquid level ranges as the structural change rate.

4. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, Converting the difference between the current real-time liquid level in the water tank and the target liquid level into a volume deviation includes: determining the corresponding volume deviation between the current real-time liquid level in the water tank and the target liquid level based on the equivalent cross-sectional area function.

5. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, Determining the total water intake demand includes: using the volume deviation as a feedback control quantity to obtain the water intake adjustment quantity, and using the water outlet flow rate at the rear end of the water tank as a balance benchmark, and corresponding the water intake adjustment quantity with the water outlet flow rate at the rear end of the water tank to form the total water intake demand.

6. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, Determining the well pump group start / stop command and the frequency conversion command includes: determining the number of operating well pumps and the well pump group rotation sequence according to the total water intake demand, single well rated flow, well pump availability status, and cumulative operating time; and determining the structural adaptive frequency limit value based on the degree of real-time liquid level change in the water tank caused by unit water intake as represented by the equivalent cross-sectional area function and the degree of capacity scale change represented by the structural change rate; wherein, when the degree of real-time liquid level change in the water tank caused by unit water intake increases or the degree of capacity scale change increases, the structural adaptive frequency limit value is reduced to limit the allowable change range of the frequency conversion command.

7. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, When the liquid level-dynamic equivalent cross-sectional area structure fingerprint has not yet covered the real-time liquid level range of the current water tank, the control device first uses the equivalent cross-sectional area function corresponding to the effective sample closest to the liquid level value of the current water tank to perform volume deviation conversion; when there is no effective sample closest to the liquid level value of the current water tank, the control device reverts to the fixed liquid level control mode.

8. The control method for a single-tank multi-well water collection system according to claim 1, characterized in that, When the real-time liquid level of the water tank, the total inflow rate, or the outflow rate at the rear end of the water tank fails the signal validity check, or the outflow rate at the rear end of the water tank cannot be directly collected by the field flow meter, or when the well pump has just started or stopped or the float switch is triggered, the control device suspends updating the liquid level-dynamic equivalent cross-sectional area structure fingerprint; when high-high liquid level, low-low liquid level, overflow, overtemperature, overpressure, dry running, communication interruption, or frequency converter failure occurs, the safety interlock directly overrides the well pump group start / stop command and the frequency converter command.

9. A control system for a single-tank multi-well water collection system, characterized in that, It includes a basic signal acquisition module, a structural sample calculation module, a structural fingerprint storage module, a volume deviation conversion module, a structural adaptive control module, a pump group sequence control module, and a safety interlock module; The basic signal acquisition module is used to directly acquire or receive the real-time liquid level of the water tank, the flow rate of each well and the water outflow at the rear end of the water tank formed by the field sensors, and to obtain the total inflow. The structural sample calculation module is used to determine a dynamic equivalent cross-sectional area sample based on the total influent flow rate, the outfluent flow rate at the rear end of the water tank, and the real-time liquid level change of the water tank. The dynamic equivalent cross-sectional area sample is the ratio of the product of the difference between the total influent flow rate and the outfluent flow rate at the rear end of the water tank multiplied by the sampling time interval between adjacent sampling times, to the difference in the real-time liquid level of the water tank at adjacent sampling times. The dynamic equivalent cross-sectional area sample is determined to be a valid sample when the direction of the real-time liquid level change of the water tank is consistent with the net flow direction determined by the difference between the total influent flow rate and the outfluent flow rate at the rear end of the water tank, the real-time liquid level change of the water tank is within the resolvable range of the water tank level sensor, and the real-time liquid level of the water tank, the total influent flow rate, and the outfluent flow rate at the rear end of the water tank pass the signal validity check. The structural fingerprint storage module is used to generate a liquid level-dynamic equivalent cross-sectional area structural fingerprint containing an equivalent cross-sectional area function and a structural change rate based on the valid samples. The module sorts the valid samples according to the real-time liquid level of the water tank, averages the valid samples within the same real-time liquid level range of the water tank to obtain the average dynamic equivalent cross-sectional area of ​​each covered real-time liquid level range, and performs piecewise linear interpolation on the average dynamic equivalent cross-sectional area of ​​adjacent covered real-time liquid level ranges to obtain the equivalent cross-sectional area function with the real-time liquid level of the water tank as the independent variable and the dynamic equivalent cross-sectional area as the function value. The slope of the equivalent cross-sectional area function between adjacent covered real-time liquid level ranges is determined as the structural change rate. The volume deviation conversion module is used to convert the liquid level difference between the current real-time liquid level of the water tank and the target liquid level into a volume deviation based on the liquid level-dynamic equivalent cross-sectional area structure fingerprint. The structure adaptive control module is used to determine the total water intake demand, the structure adaptive frequency limit value, and the frequency conversion command based on the volume deviation, the water flow rate at the rear end of the water tank, the equivalent cross-sectional area function, and the structural change rate. The structure adaptive frequency limit value is used to limit the allowable change range of the frequency conversion command relative to the previous control cycle within the current control cycle. The pump group sequence control module is used to determine the well pump group start and stop commands based on the total water intake demand output by the structure adaptive control module. The safety interlock module is used to override the well pump group start / stop command and the frequency conversion command when the safety interlock is triggered.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the control device, it implements the control method for a single-tank multi-well water collection system as described in any one of claims 1 to 8.

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