Water and fertilizer integrated irrigation system

Abstract

The application discloses a water and fertilizer integrated irrigation system and relates to the technical field of agricultural irrigation control. The water and fertilizer integrated irrigation system comprises a water source interface, a source end voltage stabilizing and purifying unit, a double-path mother liquor unit, a pulse mixing and reaction unit, a partition transportation and distribution gate control unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link referee unit, a liquid return recovery and rebalancing unit, a degraded safety shell layer and a control unit. The control unit calculates the root zone absorbability state based on pressure characteristics, phase characteristics, energy characteristics and root zone state quantity, executes the fertilizer injection and release in combination with the minimum executable irrigation volume threshold, the maximum concentration slope threshold and the unit volume available mechanical energy threshold, switches the pure water voltage stabilization or the degraded track when the thresholds are out of bounds, the state is missing or abnormal events occur, and updates the next round of scheduling by using the write-back parameters after the round ends.

Description

Technical Field

[0001] This invention relates to the field of agricultural irrigation control technology, specifically an integrated water and fertilizer irrigation system. Background Technology

[0002] Existing fertigation systems typically rely on timed irrigation or single-index threshold control, with control logic largely focused on irrigation duration, flow rate, or mixed concentration. While these systems can complete basic fertilization tasks under stable operating conditions and uniform soil types, they are prone to delays in release decisions when crops are transitioning through different growth stages, when there are significant local soil variations, or when pipeline resistance changes rapidly. This can lead to inconsistencies between the fertilization rhythm and the root zone's absorption rhythm.

[0003] Existing technologies enhance the precision of irrigation strategies through multivariate calculations. While these solutions improve state recognition capabilities, a common problem in engineering practice is insufficient coupling between the data chain and the execution chain. That is, the perception layer can identify risk trends, but the execution layer may still continue to output parameters from the previous round. When state synchronization delays, local link mismatches, or fluctuations in edge device load occur, the system is prone to control gaps where anomalies are detected but high-risk actions still occur. Fluid mechanical energy recovery, buffered power supply, or low-power scheduling are used to extend the working cycle of edge devices. These solutions play a positive role in ensuring the availability of sensing and communication, but the mechanical energy channel is often treated as an auxiliary power supply unit and does not form a direct constraint relationship with fertilizer injection release decisions. Therefore, even if the energy supply state has entered an unstable range, the control strategy may still execute according to the original fertilizer injection rhythm, making it difficult to constrain the superposition of high-energy-consuming and high-risk actions from a mechanistic perspective. In complex farmland scenarios, irrigation execution is affected not only by the mother liquor formula and hydraulic boundary but also by the root zone absorbable state, mechanical response consistency, and current available energy constraints. If a system lacks a unified overall state variable and a hierarchical judgment mechanism, a common outcome is that individual indicators meet the standards, but the overall execution is unsustainable, leading to problems such as excessive concentration fluctuations, unstable fertilization actions, prolonged anomaly recovery times, and parameter drift across cycles. Existing technologies mostly employ localized patchwork strategies to address these issues, failing to establish a unified closed loop spanning startup, steady-state, and anomaly phases. Current solutions generally lack sufficient disclosure regarding the engineering feasibility of anomaly handling sequences and recovery conditions. Events such as pressure anomalies, mechanical signature anomalies, sensor disconnection, and insufficient power supply often occur concurrently in the field. Without clear priorities and action chains, the system is prone to repeated start-ups and shutdowns or strategy jitters during anomaly transitions, affecting irrigation continuity and equipment lifespan. Even if normal operation is restored briefly, if the liquid return rebalancing result and the execution consistency result are not written back into the next round of parameter initialization, the system will repeatedly enter the same unstable range.

[0004] Therefore, there is an urgent need for an integrated water and fertilizer irrigation system that incorporates root zone absorbability status, three-threshold release, three-link judgment, mechanical energy constraint and write-back rebalancing into the same control closed loop, so as to improve the execution stability under complex working conditions, the controllability of abnormal handling and the consistency of cross-cycle operation while ensuring the accuracy of fertilizer injection. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and propose an integrated water and fertilizer irrigation system to solve the above-mentioned problems.

[0006] The objective of this invention is achieved through the following technical solution: A water and fertilizer integrated irrigation system, comprising a water source interface, a source-end pressure stabilization and purification unit, a dual-path mother liquor unit, a pulse mixing and reaction unit, a zone distribution gating unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link referee unit, a return liquid recovery and rebalancing unit, a degradation safety shell, and a control unit. The water source interface is fluidly connected to the source-end pressure stabilization and purification unit; the source-end pressure stabilization and purification unit is fluidly connected to the zone distribution gating unit via a main supply pipeline; the dual-path mother liquor unit is fluidly connected to the pulse mixing and reaction unit, and the pulse mixing and reaction unit is fluidly connected to the zone distribution gating unit; the zone distribution gating unit is fluidly connected to the irrigation branches and to the return liquid recovery and rebalancing unit via a return liquid pipeline; the return liquid recovery and rebalancing unit is fluidly connected to the dual-path mother liquor unit; the mechanical energy recovery and energy buffer unit is coupled to the main supply pipeline and the irrigation branches, supplies energy to the control unit, and outputs a mechanical signature feature; the root zone state sensing unit is signal-connected to the control unit and outputs the rate of change of root zone volumetric water content. The pulse mixing reaction unit outputs pressure characteristics, phase characteristics, and energy characteristics to the control unit based on the pressure characteristics, phase characteristics, energy characteristics, root zone volumetric water content change rate, root zone conductivity gradient, residual ion content in the return liquid, and evapotranspiration estimate. The control unit then drives the zone distribution gating unit to perform fertilizer injection release judgment. The control unit outputs fertilizer injection control command when the minimum executable irrigation volume threshold, the maximum concentration slope threshold, and the unit volume available mechanical energy threshold are simultaneously met. If any threshold is exceeded, pure water pressure stabilization control is switched. The three-link judging unit performs consistency judgment on the main link judgment result, the shadow link judgment result, and the mechanical signature verification link judgment result, and outputs efficient trajectory command, suspicious trajectory command, and downgraded trajectory command to the control unit. After each round of irrigation, the return liquid recovery and rebalancing unit writes back the mother liquor formula parameters, gating threshold parameters, mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score for the next round of startup.

[0007] The control unit writes the root zone absorbability status as the overall control intermediate quantity into the source-end pressure stabilization and purification unit, dual-path mother liquor unit, pulse mixing reaction unit, zoned distribution gating unit, three-link judgment unit, and return liquid recovery and rebalancing unit. When any unit lacks the root zone absorbability status, the fertilizer injection is stopped and the pure water pressure stabilization trajectory is switched.

[0008] The minimum executable irrigation volume threshold is defined as the lower limit threshold of the single-round zone irrigation volume, the maximum concentration slope threshold is defined as the upper limit threshold of the concentration change rate per unit time, and the available mechanical energy per unit volume threshold is defined as the lower limit threshold of the available mechanical energy per unit irrigation volume. The control unit performs fertilizer injection release when the zone irrigation volume is greater than the lower limit threshold of the single-round zone irrigation volume, the concentration change rate is less than the upper limit threshold of the concentration change rate per unit time, and the available mechanical energy per unit volume is greater than the lower limit threshold of the available mechanical energy per unit irrigation volume.

[0009] The pressure characteristics consist of the pressure peak, pressure valley and pressure recovery time within the pulse cycle; the phase characteristics consist of the interval between the fertilizer injection pulse trigger time and the zone flow response time; the energy characteristics consist of the output power density of the micro-generator module and the charge change rate of the energy buffer unit; and the control unit performs back-calculation of the pipeline impedance based on the above characteristics.

[0010] When the main link judgment result, shadow link judgment result, and mechanical signature verification link judgment result are consistent, the three-link adjudication unit outputs an efficient trajectory instruction. When the main link judgment result and shadow link judgment result are consistent but the mechanical signature verification link judgment result is inconsistent, it outputs a suspicious trajectory instruction and the control unit lowers the single fertilizer injection limit and triggers a local backflash retest. When the three-link judgment results conflict, it outputs a downgrade trajectory instruction and the control unit triggers low-power protection.

[0011] When the available mechanical energy per unit volume is lower than the lower limit threshold of available mechanical energy per unit irrigation volume, the control unit first controls the system to execute the low-energy pure water pressure stabilization section and then sets the high-energy fertilizer injection section. After the available mechanical energy per unit volume recovers to the lower limit threshold of available mechanical energy per unit irrigation volume, the fertilizer injection release judgment is restarted.

[0012] After each irrigation cycle, the liquid recovery and rebalancing unit writes back the mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score. The control unit updates the mother liquor injection cycle, gating threshold combination, and partition priority based on the write-back results during the next start-up phase.

[0013] During the startup phase, the control unit first performs a fertilizer-free impedance scan and establishes a mechanical energy recovery baseline. Then, it performs a low-dose wave packet trial injection and generates the first round of absorbable window. After the first round of absorbable window reaches the preset increase, it enters the steady-state fertilizer injection irrigation phase.

[0014] During the steady-state phase, the control unit uses the target absorption improvement amount reaching the preset termination target value as the round termination condition, and constrains the upper limit of mother liquor concentration, the upper limit of fertilizer injection pulse frequency, the upper limit of return liquid reuse ratio, and the water hammer risk boundary throughout the process.

[0015] During abnormal phases, the control unit executes a graded strategy in sequence: pressure over-limit handling, mechanical signature abnormal handling, sensor disconnection handling, and insufficient power supply handling. Pressure over-limit handling triggers pure water pressure stabilization, mechanical signature abnormal handling triggers local backflush retesting, sensor disconnection handling triggers mechanical signature weight increase and pressure reduction of fertilizer injection limit, and insufficient power supply handling triggers low power protection and unlocks in segments according to the energy recovery curve.

[0016] The beneficial effects of this invention are: This invention forms a synchronous closed loop of information, material, and execution chains through the unified organization of a water source interface, a source-end pressure stabilization and purification unit, a dual-path mother liquor unit, a pulse mixing and reaction unit, a zoned distribution gating unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link adjudication unit, a return liquid recovery and rebalancing unit, a degraded safety shell, and a control unit. Compared to conventional systems that primarily focus on liquid supply or distribution, this invention solidifies connectivity and control relationships within the same architecture, enabling continuous completion of state acquisition, release judgment, trajectory switching, and write-back updates within the same cycle. This reduces the risk of data updates occurring without corresponding updates to the execution strategy and improves system consistency across different cycles.

[0017] This invention uses the root zone's absorbability as a core governing intermediate quantity in fertilization control. Compared to strategies driven by a single humidity or conductivity index, it unifies the rate of change in root zone volumetric water content, root zone conductivity gradient, residual ions in the return liquid, evapotranspiration estimation, and pressure, phase, and energy characteristics into a single decision-making caliber. This unified state quantity can be directly used for release determination and trajectory assessment, avoiding decision conflicts caused by independent triggering of multiple inputs. This ensures higher consistency between control actions and the crop's root zone absorption window, and gives the same control strategy more stable migration capabilities across different plots and stages.

[0018] This invention employs a three-threshold parallel release mechanism consisting of a minimum executable irrigation volume threshold, a maximum concentration slope threshold, and a unit volume available mechanical energy threshold. Compared to existing methods that only set volume or concentration thresholds, this mechanism simultaneously constrains operational feasibility, mixing stability, and edge execution capability. It can identify potential risks where local indicators meet standards but overall execution is unsustainable before release. When any threshold is exceeded, the control unit immediately switches to the pure water pressure stabilization trajectory and records the type of exceedance, ensuring operational continuity while suppressing the spread of abnormal actions in subsequent cycles, thereby improving the boundary controllability of the fertilization process.

[0019] This invention employs a three-link adjudication mechanism, comprising the main link judgment result, the shadow link judgment result, and the mechanical signature verification link judgment result. This mechanism enables real-time judgment, trend verification, and physical execution consistency to be cross-validated within the same cycle. Compared to a single-link control mode, this mechanism can output a suspicious trajectory and proactively reduce the single-injection limit when the main link and shadow link are consistent but the mechanical signature is inconsistent. This allows for earlier identification of hidden anomalies such as valve jamming, partial blockage, and bypass leakage. When there is a conflict between the three links, a degraded trajectory is entered and low-power protection is triggered, which can significantly reduce the probability of false release and improve the policy interpretability during the anomaly phase.

[0020] In terms of state synchronization, this invention writes the absorbable state of the root region into multiple controlled units and directly couples the state missing criterion to the release link. Compared with a strategy that only reports errors at the acquisition layer without interrupting execution, this design can stop fertilizer injection and release and switch to the pure water pressure stabilization trajectory when any critical unit lacks a valid state, thus preventing local units from continuing to execute with expired states. By making state integrity a prerequisite for execution, this invention can maintain a conservative and continuous operating state under conditions of communication jitter, node restart, or short-term disconnection, reducing control drift during abnormal periods.

[0021] This invention directly incorporates the results of mechanical energy recovery and energy buffering into the execution capability boundary, and reorders the timing of the low-energy-consuming pure water pressure stabilization stage and the high-energy-consuming fertilizer injection stage when mechanical energy is insufficient. Compared to the strategy of directly stopping irrigation when energy supply is insufficient, this method can gradually restore high-energy-consuming actions while ensuring key data collection and basic pressure stabilization. This avoids execution oscillations caused by frequent start-stop cycles and reduces control abrupt changes during the energy supply recovery phase. With the segmented unlocking mechanism, the system can gradually restore local backflushing, low-upper-limit fertilizer injection, and full-function trajectory referencing according to the energy recovery progress, improving the continuous operation capability under complex conditions.

[0022] This invention utilizes a liquid recovery and rebalancing unit to write back the mother liquor formulation parameters, gating threshold parameters, mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score after each cycle. This allows the next cycle to be started based on the actual execution results of the previous cycle, updating the parameters accordingly. Compared to fixed parameters or manual periodic parameter tuning, this write-back mechanism can absorb hardware degradation, operating condition drift, and execution deviations in advance during the initialization stage, reducing the accumulation of parameter drift over long-term operation. Therefore, this invention improves the system's adaptability and engineering maintenance efficiency while maintaining fertilizer injection accuracy, and enhances the stability and feasibility of operation throughout its entire lifecycle. Attached Figure Description

[0023] Figure 1 The process of this invention Figure 1 ; Figure 2 The process of this invention Figure 2 ; Figure 3 The process of this invention Figure 3 . Detailed Implementation

[0024] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1 like Figure 1 As shown, this embodiment discloses a basic executable scheme for an integrated water and fertilizer irrigation system. The system consists of a water source interface, a source-end pressure stabilization and purification unit, a dual-path mother liquor unit, a pulse mixing and reaction unit, a zoned distribution gating unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link referee unit, a return liquid recovery and rebalancing unit, a degraded safety shell, and a control unit. The water source interface is fluidly connected to the source-end pressure stabilization and purification unit, the source-end pressure stabilization and purification unit is fluidly connected to the zoned distribution gating unit via the main liquid supply pipeline, the dual-path mother liquor unit is fluidly connected to the pulse mixing and reaction unit, and the pulse mixing and reaction unit is fluidly connected to the zoned distribution gating unit. The zoned distribution gate unit is fluidly connected to the irrigation branch and fluidly connected to the return liquid recovery and rebalancing unit via the return liquid pipeline. The return liquid recovery and rebalancing unit is fluidly connected to the dual-path mother liquor unit. The mechanical energy recovery and energy buffer unit is coupled to the main supply pipeline and the irrigation branch and supplies energy to the control unit and outputs mechanical signature characteristics. The root zone state sensing unit is signal-connected to the control unit and outputs the root zone volumetric water content change rate, root zone conductivity gradient, return liquid ion residue, and evapotranspiration estimate. The pulse mixing reaction unit outputs pressure characteristics, phase characteristics, and energy characteristics to the control unit. The control unit calculates the root zone absorbability status based on the above characteristics and performs fertilizer injection release determination.

[0026] In this embodiment, the data acquisition link includes pressure sensors at the inlet of the pulse mixing reaction unit and the inlet of the zoned distribution gating unit, with a sampling frequency of 20Hz; flow sensors at the inlet of each zone branch, with a sampling frequency of 10Hz; root zone volumetric water content sensors and root zone conductivity sensors at the effective depth of the crop root layer, with a sampling period of 60s; residual ions in the return liquid are sampled every 30s by the online ion meter of the return liquid recovery and rebalancing unit; and evapotranspiration estimates are updated every 300s by the estimation model based on ambient temperature, humidity, irradiance, and wind speed inputs. The control unit performs time alignment with a control cycle of 1s, first using a sliding window median filter to suppress spikes, and then using a first-order low-pass filter to obtain a smooth sequence. The initial window lengths are 5 points and 10 points, derived from engineering constraints on valve action response time and pressure wave propagation time. If the response times of the field equipment differ, the median window length is adjusted. With low-pass window length As parameters to be calibrated, and reset to 0.2 to 0.5 times the duration of a single valve action, the recommended initial value range is as follows: point, The calibration trigger condition is the first start after the valve or pump body is replaced, and the update frequency is once after each irrigation cycle ends.

[0027] The pressure characteristic output of the pulse mixing reaction unit is defined as the combination of the pressure peak, pressure trough, and pressure recovery time within the pulse cycle, expressed as: in To control the periodic index, For the first Cyclic pressure characteristics This represents the peak pressure of the cycle. This represents the trough value of the pressure during this period. The time it takes for the pressure to recover from the trough to the steady-state threshold. and The weights are normalized and are all parameters to be calibrated. Their initial values ​​are 0.62 and 0.38, respectively, with value ranges of [missing values]. and The data source is the fitting of impedance scan samples without fertilizer during the initial stage, and the update frequency is once every 3 irrigation cycles. The phase feature is defined as the interval between the fertilizer injection pulse trigger time and the zone flow response time, expressed as follows: in For the first Periodic phase characteristics, The moment when the partition traffic reaches the response threshold. This refers to the trigger moment of the fertilizer injection pulse. The energy characteristics are composed of the output power density and rate of change of charge of the mechanical energy recovery and energy buffer unit, expressed as follows: in For the first Periodic energy characteristics For power density, This represents the rate of change of charge per unit time.

[0028] The control unit performs back-calculation of the pipeline impedance based on pressure and phase characteristics, expressed as follows: in For the first Estimation of periodic pipeline network impedance. This represents the peak flow rate for that period. To prevent tiny positive numbers with a denominator of zero, and The parameters to be calibrated have initial values ​​of 1.15 and 0.42, with value ranges of [missing values]. and The data source is the impedance scan fitting during the initial fertilizer-free phase, and the update frequency is once after each irrigation cycle. The root zone absorbability state is expressed using a bounded mapping. in For the first Absorbable states in the periodic root region It is a sigmoid mapping function. The rate of change of volumetric water content in the root zone. The root region conductivity gradient, This refers to the residual ion content in the returned liquid. For the estimation of evaporation, to For the parameters to be calibrated, the initial value vector is taken as follows: ,in The range of values ​​for the remaining coefficients is as follows: The sample source is the combined data of the initiation phase of non-fertilizer impedance scanning and low-dose wave packet trial injection. The update trigger condition is the end of the round and no state loss occurs. The update frequency is once per round.

[0029] The control unit calculates the single-cycle zone irrigation volume, concentration change rate, and available mechanical energy per unit volume in each cycle and implements a three-threshold gating system, where the single-cycle zone irrigation volume is denoted as... The minimum executable irrigation volume threshold is defined as For the area of ​​the zone, For the target wetting depth, This is the soil porosity correction coefficient and a parameter to be calibrated. The initial value is 0.88, and the range is... The data is derived from the conversion between on-site soil bulk density and field water holding capacity, and is updated once per crop stage; the concentration change rate is denoted as... in For the first Periodic mixing output concentration, To control the cycle duration and set it to 1 second, the maximum concentration slope threshold is defined as follows: in It is the 0.95 quantile function. This is the baseline sample set for pure water pressure stabilization during the startup phase; the mechanical energy per unit volume can be denoted as... in The energy available for the buffer unit To safely conserve energy, the mechanical energy threshold per unit volume can be defined as follows: in For valve control action energy consumption budget, For the energy consumption budget of the sensing link, To control the calculated energy consumption budget, a coefficient of 1.2 is used as the project's safety margin. If there are significant fluctuations in on-site energy supply, this should be changed to a parameter to be calibrated. And the solution is obtained based on the criterion that the probability of energy deficit in the past 10 rounds is no higher than 5%. Initial value is 1.20, range of values The update frequency is once every 5 rounds of irrigation.

[0030] The quantification of fertilizer release judgment is as follows: in As a result of the release, For indicator functions, The threshold for allowing the root region to be absorbable is set. From the low-dose wavelet injection phase The 0.60 quantile of the sample is given. If... The control unit outputs fertilizer injection control commands and drives the zone distribution gating unit to perform fertilizer injection for this cycle; if any threshold is exceeded, the pure water pressure stabilization control is immediately switched and the type and time of the exceedance are recorded.

[0031] The three-link adjudication unit performs consistency adjudication on the main link judgment result, the shadow link judgment result, and the machine signature verification link judgment result. The main link judgment result is denoted as... And the release decision is based on the current cycle. The shadow link determination result is denoted as: ; in The shadow link window length is determined using a conservative criterion based on the most recent 5 control cycles and calculated based on the number of available cycles during the initial startup phase, with a fixed window length of 5. The mechanical signature verification link determination result is recorded as follows. in and The mean of the baseline without abnormalities. and This is three times the median absolute deviation limit of the baseline sample. When all three chains are consistent, an efficient trajectory command is output. When the main link and shadow link are consistent but the mechanical signature verification link is inconsistent, a suspicious trajectory command is output, the single fertilization limit is reduced, and a local backflash retest is triggered. When there is a conflict among the three chains, a degraded trajectory command is output, and a low-power protection is performed by the degraded security shell.

[0032] Control unit parallel computing window execution consistency score ; With execution risk score ; in For the most recent Number of inconsistencies in the three chains within a control cycle. This represents the total number of periods in the window. The risk assessment window length is a parameter to be calibrated; the initial value is 30 periods, and the range is [not specified]. The data is sourced from risk sample statistics during the initial phase and is updated once per round. For the first Cyclical risk scoring and The initial values ​​for the weights to be calibrated are 0.55 and 0.45, respectively, and satisfy the following conditions: The value range is ;when Output suspicious trajectory warnings and lock fertilizer injection limits in real time. It outputs a warning about the degradation trajectory and enters low-power protection mode. and The threshold to be calibrated and satisfies The initial values ​​are taken from the 0.80 and 0.95 quantiles of the baseline risk score sample, respectively, and are updated every 5 rounds. The degradation trajectory recovery condition is set as follows: three thresholds must be met consecutively for 3 control cycles, and three-chain consistency must be met consecutively for 3 control cycles. Simultaneously, it is required that… After recovery, the pure water pressure stabilization transition section is executed first, and then the fertilizer injection release judgment is unlocked.

[0033] After each irrigation cycle, the liquid recovery and rebalancing unit writes the mother liquor formula parameters, gating threshold parameters, mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score into the write-back record object. The mechanical energy recovery efficiency is defined as ; Pressure wave attenuation coefficient is defined as ; The execution consistency score is defined as follows: ; For irrigation cycle indexing, For the first Wheel recovers energy, This provides hydraulic input energy for the vessel. and These are the pressure wave amplitudes at the wheel end and wheel front, respectively. The number of inconsistencies in the three chains. This represents the total number of cycles in this round. The write-back record object uses a JSON structure and is persisted to the local parameter table `rw_round_log` of the control unit. The key fields are the round number and partition number, and the value fields are the mother liquor formula parameters, gate threshold parameters, etc. , , and timestamp. Control parameter vector Dimensions The fields are, in order: mother liquor injection cycle time, volume threshold coefficient, concentration slope threshold coefficient, mechanical energy threshold coefficient, partition priority weight, and backflush duration; write-back parameter vector The same dimension The initial value is given by the results of the first round of impedance scan without fat. The control unit, in the next round of startup, calls the write-back record object and presses... Update the mother liquor injection cycle time, gating threshold combination, and partition priority, among which... This is the forgetting factor and a parameter to be calibrated, with an initial value of 0.72 and a range of values. The data is sourced from the stability statistics of the last 5 rounds of write-back. The trigger condition is the end of the current round and the write-back fields are complete. The update frequency is once per round. If a field is missing, the parameter update is frozen and the system is forced to enter the pure water pressure stabilization trajectory.

[0034] This embodiment employs an execution sequence of state calculation first, threshold release second, referee error correction in parallel, and write-back rebalancing closed loop. The root region absorbability state unifies moisture, salinity, evapotranspiration, and energy availability into a single decision quantity, avoiding misapplication caused by triggering fertilization based solely on humidity or conductivity. The three-threshold structure constrains operational feasibility to the intersection of volume boundary, concentration change boundary, and energy supply boundary, preventing local indicators from meeting standards but the entire round of execution from being unsustainable. The mechanical signature verification link uses pressure-phase consistency constraints to identify hidden anomalies such as valve jamming, local blockage, and bypass leakage, suppressing the risk of misjudgment and release in the main link. The write-back rebalancing mechanism feeds back the credibility of the current round of execution to the parameter initialization of the next round, allowing hardware degradation and operating condition drift to be absorbed in advance during long-term operation.

[0035] Example 2 like Figure 1 and Figure 2 As shown, this embodiment enhances the entire-link control execution based on the operable closed-loop of Embodiment 1. The enhancements focus on four aspects: the overall broadcast of root zone absorbability status, rigid interception of missing status, dynamic loading with three thresholds, and combined impedance back-calculation based on pressure, phase, and energy characteristics. This elevates fertilizer injection release from localized judgment to consistent, executable judgment across the entire link. The system hardware configuration and fluid connectivity remain consistent with Embodiment 1. Basic engineering parameters are the same as in Embodiment 1: pressure sampling frequency is 20Hz, flow sampling frequency is 10Hz, root zone volumetric water content and root zone conductivity sampling periods are 60s, control period is 1s, and the filtering window is 5 points of median filtering and 10 points of first-order low-pass filtering. The control unit generates a root zone absorbability status data packet in each control cycle and writes it to the source-end pressure stabilization and purification unit, dual-path mother liquor unit, pulse mixing reaction unit, zoned distribution gating unit, three-link judgment unit, and return liquid recovery and rebalancing unit. The status data packet is defined as... in To control the periodic index, This represents the root region's absorbability state. For state credibility, For estimating the network impedance, This is the status version number. This is the time when the state expires.

[0036] State reliability is directly calculated from the availability of leaf node inputs, expressed as: in This represents the number of missing input channels within the most recent risk assessment window. The risk assessment window length is the same as in Example 1. That is, the initial value is 30 control cycles, and the value range is... , The total number of input channels is fixed at 7, corresponding to pressure characteristics, phase characteristics, energy characteristics, root zone volumetric water content change rate, root zone conductivity gradient, residual ions in the return liquid, and evapotranspiration estimation. The control unit broadcasts the status data packets via the industrial bus at 1-second intervals, and each unit sends back a timestamp and version confirmation. The state valid flag is defined as in For the current moment, For unit The last time it was received, The heartbeat timeout threshold is initially set to 2 seconds, and the value is determined based on twice the engineering redundancy of the broadcast cycle. This is the unit-side status version number. The minimum confidence threshold is set, and the initial value is taken as the 0.10 quantile of the baseline confidence sample. The state expires at the time of state broadcast plus the expiration window. get, The initial value is 3s. These correspond to six controlled units. The criterion for missing state across the entire chain is defined as follows: ; when At that time, the control unit forcibly shuts down the fertilizer injection release and switches to the pure water pressure stabilization trajectory, and freezes the current wheel gate parameter update.

[0037] In this embodiment, the pressure, phase, and energy characteristics output by the pulse mixing reaction unit are organized using a unified feature frame. The pressure feature frame is... in The peak pressure of the pulse cycle. The pressure trough value during the pulse cycle. Pressure recovery time; phase characteristics are defined as follows: in For the partition traffic response time, The timing of the fertilizer injection pulse trigger; the energy characteristic frame is... in To the output power density of the recovery unit, Let be the rate of change of charge of the buffer unit. The control unit performs impedance back-calculation based on three types of characteristics, expressed as follows: in Peak traffic, To prevent division by positive numbers, to The initial value vector is taken as the calibration coefficient. The range of values ​​for each coefficient is as follows: The sample source is the combined sample of non-fertilizer impedance scanning and low-dose wave packet injection during the initiation phase. The update trigger condition is the end of the round and the missing state interception is not triggered. The update frequency is once per round.

[0038] The absorbability state in the root region is still calculated using bounded mapping, but in this embodiment, a state reliability coupling term is introduced to suppress input missing amplification errors. The joint energy feature scalar is defined as follows: in and The weights are normalized and are all parameters to be calibrated. Their initial values ​​are 0.58 and 0.42, respectively, with value ranges of [missing values]. and The update frequency is once every 3 rounds; the root region absorbability state expression is: in It is a sigmoid mapping function. The rate of change of volumetric water content in the root zone. The root region conductivity gradient, This refers to the residual ion content in the returned liquid. For the estimation of evaporation, to For the parameters to be calibrated, the initial value vector is taken as follows: ,in The range of values ​​for the remaining coefficients is as follows: The parameter update cycle is once after each round of irrigation. If the trigger state is missing during the current round, only the sample is recorded and the coefficient is not updated.

[0039] In this embodiment, the three-threshold release method adopts dynamic loading with dual indexes of partition and crop stage. The dynamic thresholds are defined as follows: in For the partitioned soil category index, Index of crop growth stages , , The threshold loading coefficients are initially set to 1.00 for all three, with recommended value ranges as follows: , , The loading coefficients are derived from the parameter table `thr_profile`, whose fields are defined as `r_z`, `s_g`, `xi_V`, `xi_S`, `xi_E`, `version`, `timestamp`, and `source_batch`, where `source_batch` is the corresponding calibration sample batch number, `version` is the parameter version number, and `timestamp` is the effective timestamp. The parameter table is generated by jointly fitting the non-hyperthermal impedance scanning samples and low-dose wave packet trial injection samples during the initial phase, and the version is updated based on the write-back record objects after each round. The loading coefficients are updated smoothly. in The smoothing factor is initially set to 0.70, with a range of values... The data is sourced from statistics on threshold fluctuations over the past five rounds. This is the value retrieved from the current index. The lookup is triggered by entering a new round or phase switch; prohibited by valid interception due to missing status; and restored by three consecutive valid status cycles. .

[0040] The control unit first calculates the basic release criteria. in For single-round zoned irrigation volume, The concentration change rate The usable mechanical energy per unit volume The threshold for release status is set, and the initial value is taken as the low-dose wave packet trial injection stage. The 0.60 quantile of the sample; then superimposed with the state-deficient interception to obtain the final release criterion. The execution instruction is defined as follows in Fertilizer injection instructions for the periodic plan, This refers to the actual execution of the instruction. When and When this occurs, the control unit determines that the state link is mismatched and blocked, and outputs a suspicious trajectory event to the three-link adjudication unit.

[0041] This embodiment provides a minimum executable rule for the update object, and the gate parameter object is denoted as... The update is triggered when the round ends and The updated formula is as follows in Write back the parameter vector for the liquid recovery and rebalancing unit. The forgetting factor is initially set to 0.74, with a range of values... The data is sourced from the stability statistics of the last 5 write cycles; the freezing condition is the absence of any key field or Keep frozen The rollback condition is that the consistency score is lower than the lower threshold for two consecutive rounds of execution. During rollback, the parameters will be restored to the snapshot version that passed the consistency check in the most recent round. The initial value is taken as the 0.10 quantile of the consistency score of the most recent 5 rounds of healthy samples. The parameter object dimension is... The fields are ordered as follows: mother liquor injection cycle time, volume threshold coefficient, concentration slope threshold coefficient, mechanical energy threshold coefficient, partition priority weight, and local backflush duration. The initial values ​​are from the first round of calibration results in Example 1, and the update frequency is once per round.

[0042] The root zone absorbability status is written as a required input for the entire chain through version consistency and reliability gating, directly cutting off the hidden danger of local units continuing to allow the old status; the three-threshold dynamic loading explicitly maps the differences in soil type and growth stage to three constraint surfaces of volume, concentration and energy, reducing the probability of misjudgment when fixed thresholds are run across stages; pressure characteristics, phase characteristics and energy characteristics jointly participate in impedance back-inference, so that mechanical response anomalies can be amplified and identified before fertilization, rather than being passively corrected after the result deviation; the freeze and rollback mechanism ensures that no parameter drift occurs during the state missing period, avoiding the inheritance of pollution parameters in the next round of startup.

[0043] Example 3 like Figures 1 to 3 As shown, this embodiment, based on the system configuration of Embodiments 1 and 2, configures the control unit in a high-order scenario execution mode. The system still consists of a water source interface, a source-end pressure stabilization and purification unit, a dual-path mother liquor unit, a pulse mixing reaction unit, a zoned distribution gating unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link referee unit, a return liquid recovery and rebalancing unit, a degraded safety shell, and a control unit. The control objective is expanded from single-round fertilizer injection release to a full-cycle closed loop encompassing the start-up phase, steady-state phase, and abnormal phase. The basic engineering parameters are referenced as follows: sampling frequency, sampling period, control period, and filtering window are the same as in Embodiment 1; the status data packet broadcast period, heartbeat timeout threshold, and status expiration window are the same as in Embodiment 2. In each control cycle, the control unit collects pressure characteristics, phase characteristics, energy characteristics, root zone volumetric water content change rate, root zone conductivity gradient, return liquid ion residue, and evapotranspiration estimate, and uniformly calculates the root zone absorbability state. Mechanical energy available per unit volume and trajectory state variables ,in For controlling the periodic index.

[0044] In the initiation phase, a fertilizer-free impedance scan is first performed to establish a mechanical energy recovery baseline, followed by a low-dose wavelet trial injection to generate the first round of absorbable windows. The fertilizer-free impedance scan window is denoted as... The low-dose wavelet injection window is denoted as The median absorbability of the window is defined as follows: The first round of absorbable window increase is defined as when and At that time, the control unit switches the system to the steady-state fertilizer injection and irrigation stage, in which... The preset increase threshold is given by the 0.60 quantile of the historical baseline sample, with an initial value of 0.08 and a recommended range. The update frequency is once per crop stage. The threshold value represents the lower limit of available mechanical energy per unit irrigation volume.

[0045] The three-link adjudication unit receives the main link's judgment result. Shadow link determination results And the mechanical signature verification link judgment result It then outputs trajectory instructions according to consistency logic. The trajectory state variables are defined as follows: in Indicates an efficient trajectory. Indicates suspicious trajectory, This indicates the downgrade trajectory. The upper limit of the periodic fertilizer injection is denoted as... Its initialization rule is in The planned fertilizer injection limit is generated during the low-dose wave packet trial injection in the initial phase, with an initial value of 0.90 L / min and a range of values. The control unit is in The maximum single fertilizer injection limit will be updated to And trigger a local backflip retest, in which The limiting coefficient to be calibrated is initially set to 0.65, with a range of values... The data is sourced from statistics on the stability of fertilizer injection based on suspicious trajectories from the past five rounds, and is updated every three rounds. When the low-power protection is triggered, the high-power fertilizer injection action is paused.

[0046] When the available mechanical energy per unit volume is lower than the lower limit threshold of available mechanical energy per unit irrigation volume, the control unit performs a time-series rearrangement, placing the low-energy-consuming pure water pressure stabilization section before the high-energy-consuming fertilizer injection section. The energy insufficiency criterion is defined as follows: when The current cycle fertilizer injection execution command is set to zero and pure water pressure is maintained, denoted as... in This is the current cycle's pure water pressure stabilization plan instruction; when continuous Each control cycle satisfies The determination of whether to reinstate fertilizer injection and release is as follows: To restore the holding period and obtain it from the pump and valve response settling time calibration, the initial value is taken as 5 control cycles, and the value range is... Insufficient power supply is addressed using a segmented unlocking mechanism based on an energy recovery curve, with the segment threshold defined as follows: , , ,when At times, only status acquisition and pure water pressure stabilization are retained; when When the local recoil capability is unlocked; when Unlock low cap fertilizer at times; when The full functionality of trajectory refereeing and fertilizer injection execution will be restored in time.

[0047] The steady-state phase terminates when the target increase in absorbability reaches a preset termination value, and throughout the process, it constrains the upper limits of mother liquor concentration, fertilizer injection pulse frequency, return liquid reuse ratio, and water hammer risk boundary. The target increase in absorbability is defined as follows: in This is the steady-state initiation period of the cycle; the termination criterion is defined as follows: in The initial value is set to 0.22, and the range is [specified]. ; For mixing concentration, The initial value is 2.0 g / L, which is the upper limit of the mother liquor concentration. The frequency of the fertilizer injection pulse. This is the upper limit of the pulse frequency, with an initial value of 0.20Hz; The proportion of recycled liquid is used for reuse. This is the upper limit for the proportion of recycled liquid, with an initial value of 0.35; This refers to the water hammer risk index. The water hammer risk index is defined as follows: in and For engineering limits, and The weights are normalized and calibrated using the starting baseline samples, with initial values ​​of 0.57 and 0.43 respectively, and satisfying the following conditions: After the cycle ends, the action chain executes in a fixed sequence: the control unit outputs a termination command and closes the fertilizer injection valve, followed by the pure water pressure stabilization flushing section. After each control cycle, the liquid return recovery and rebalancing unit is triggered to write back and solidify the status log for this cycle, and finally, it switches to the next startup phase. The flushing maintenance cycle is determined by the pipeline residual liquid replacement time. The initial value is taken as 8 control cycles, and the value range is... .

[0048] During the anomaly phase, a tiered strategy is implemented sequentially for handling pressure exceedances, mechanical signature anomalies, sensor disconnections, and insufficient power supply. Pressure exceedance events, mechanical signature anomalies, sensor disconnections, and insufficient power supply events are respectively denoted as follows: , , and Its criterion is defined as follows: in For the most recent Count of lost channels within each control cycle The length of the statistical window for lost contact is set to 10 control periods initially. The most recent valid sensor feedback time. The current moment; , , , , and These are the upper limit for peak pressure, the upper limit for pressure change rate, the phase deviation threshold, the pressure deviation threshold, the disconnection channel threshold, and the disconnection timeout threshold, respectively. The initial values ​​are 0.55 MPa, 0.12 MPa / s, 0.30 s, 0.05 MPa, 2, and 4 s, respectively, all given by the baseline sample quantile statistics or engineering safety limits. The control unit generates abnormal handling actions according to a fixed priority order. action It corresponds to pure water pressure stabilization and performs pressure relief; action Corresponding local backflip retest and recalculation of mechanical signature consistency; action The corresponding mechanical signature weight is increased and the fertilizer injection limit is reduced. The mechanical signature weight is denoted as... Its initialization rule is The initial values ​​are derived from the baseline mechanical signature consistency statistics and range from [specific value range]. The weights and upper limits have been updated to... in The initial value is 0.08. Take 0.70, The initial value is 0.75 and the range of values ​​is... ;action Corresponding to low-power protection and segmented unlocking; Actions The current trajectory should be maintained.

[0049] The liquid recovery and rebalancing unit writes back the mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score after each irrigation cycle, and these scores, together with the mother liquor formulation parameters and gating threshold parameters, form a cross-cycle update vector. The core fields for writing back are calculated as follows: in For irrigation cycle indexing, For the first Wheel recovers energy, For the first The turbine inputs hydraulic energy. and These are the pressure wave amplitudes at the wheel end and wheel front, respectively. The number of inconsistencies in the three chains. This represents the total number of cycles in this round. Control parameter vector. Dimension is defined as The fields are ordered as follows: mother liquor injection cycle time, volume threshold coefficient, concentration slope threshold coefficient, mechanical energy threshold coefficient, partition priority weight, and local backflush duration; write-back parameter vector The same dimension And the field order is the same as Consistent. The control unit will press [the button] in the next startup phase. Update the mother liquor injection cycle time, gating threshold combination, and partition priority, among which... The forgetting factor is initially set to 0.76, with a range of values... The update frequency is once per round; if the write-back field is missing, the parameter update is frozen and the previous round of parameter snapshot is maintained.

[0050] This embodiment achieves strongly coupled operation through a two-stage baseline establishment, steady-state constraint closed-loop execution, hierarchical and sequential handling of anomalies, and write-back-driven cross-round parameter tuning. The mechanical signature verification link advances the physical execution consistency to the fertilizer injection permission determination, the segmented unlocking of energy supply directly transforms the energy state into the executable capability boundary, and the write-back mechanism feeds back the energy recovery efficiency and execution consistency of the previous round as the scheduling prior for the next round. These three, together with the root region absorbability state, constitute an inseparable control closed loop.

[0051] The above description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be modified within the scope of the concept described herein by means of the above teachings or the technology or knowledge in related fields.

Claims

1. A water and fertilizer integrated irrigation system, characterized in that, The system includes a water source interface, a source-end pressure stabilization and purification unit, a dual-path mother liquor unit, a pulse mixing reaction unit, a zone distribution gating unit, a root zone state sensing unit, a mechanical energy recovery and energy buffer unit, a three-link referee unit, a return liquid recovery and rebalancing unit, a degradation safety shell, and a control unit. The water source interface is fluidly connected to the source-end pressure stabilization and purification unit. The source-end pressure stabilization and purification unit is fluidly connected to the zone distribution gating unit via the main supply pipeline. The dual-path mother liquor unit is fluidly connected to the pulse mixing reaction unit, and the pulse mixing reaction unit is also fluidly connected to the zone distribution gating unit. The zone distribution gating unit is fluidly connected to the irrigation branch and to the return liquid recovery and rebalancing unit via the return liquid pipeline. The return liquid recovery and rebalancing unit is fluidly connected to the dual-path mother liquor unit. The mechanical energy recovery and energy buffer unit is coupled to the main supply pipeline and the irrigation branch, supplies energy to the control unit, and outputs a mechanical signature feature. The root zone state sensing unit is signal-connected to the control unit and outputs the root zone volumetric water content change rate, the root zone conductivity gradient, and the return liquid ion concentration. The pulse mixing reaction unit outputs pressure characteristics, phase characteristics, and energy characteristics to the control unit based on the residual amount and evapotranspiration estimate. The control unit calculates the root zone absorbability state based on the pressure characteristics, phase characteristics, energy characteristics, root zone volumetric water content change rate, root zone conductivity gradient, residual ion amount in the return liquid, and evapotranspiration estimate, and drives the zone distribution gating unit to perform fertilizer injection release judgment. The control unit outputs fertilizer injection control command when the minimum executable irrigation volume threshold, the maximum concentration slope threshold, and the unit volume available mechanical energy threshold are simultaneously met, and switches to pure water pressure stabilization control when any threshold is exceeded. The three-link judging unit performs consistency judgment on the main link judgment result, the shadow link judgment result, and the mechanical signature verification link judgment result, and outputs efficient trajectory command, suspicious trajectory command, and downgraded trajectory command to the control unit. The return liquid recovery and rebalancing unit writes back the mother liquor formula parameters, gating threshold parameters, mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score after each round of irrigation for the next round of start-up.

2. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The control unit writes the root zone absorbability status as the overall control intermediate quantity into the source-end pressure stabilization and purification unit, the dual-path mother liquor unit, the pulse mixing reaction unit, the zoned distribution gating unit, the three-link judgment unit, and the return liquid recovery and rebalancing unit. When any unit lacks the root zone absorbability status, the fertilizer injection is stopped and the pure water pressure stabilization trajectory is switched.

3. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The minimum executable irrigation volume threshold is defined as the lower limit threshold of a single-round zone irrigation volume, the maximum concentration slope threshold is defined as the upper limit threshold of the concentration change rate per unit time, and the unit volume available mechanical energy threshold is defined as the lower limit threshold of available mechanical energy corresponding to a unit irrigation volume. The control unit performs fertilizer injection release when the zone irrigation volume is greater than the lower limit threshold of the single-round zone irrigation volume, the concentration change rate is less than the upper limit threshold of the concentration change rate per unit time, and the unit volume available mechanical energy is greater than the lower limit threshold of available mechanical energy corresponding to a unit irrigation volume.

4. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The pressure characteristics consist of the pressure peak value, pressure valley value and pressure recovery time within the pulse cycle; the phase characteristics consist of the interval between the fertilizer injection pulse trigger time and the zone flow response time; the energy characteristics consist of the output power density of the micro-generator module and the charge change rate of the energy buffer unit; and the control unit performs pipeline impedance back-calculation based on the above characteristics.

5. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The three-link adjudication unit outputs an efficient trajectory instruction when the main link judgment result, the shadow link judgment result, and the mechanical signature verification link judgment result are consistent. When the main link judgment result and the shadow link judgment result are consistent but the mechanical signature verification link judgment result is inconsistent, it outputs a suspicious trajectory instruction and the control unit lowers the single fertilizer injection limit and triggers a local backflash retest. When the three-link judgment results conflict, it outputs a downgrade trajectory instruction and the control unit triggers low-power protection.

6. The integrated water and fertilizer irrigation system according to claim 3, characterized in that, When the available mechanical energy per unit volume is lower than the lower limit threshold of available mechanical energy per unit irrigation volume, the control unit first controls the system to execute the low-energy pure water pressure stabilization section and then sets the high-energy fertilizer injection section. After the available mechanical energy per unit volume recovers to the lower limit threshold of available mechanical energy per unit irrigation volume, the fertilizer injection release judgment is restarted.

7. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The liquid recovery and rebalancing unit writes back the mechanical energy recovery efficiency, pressure wave attenuation coefficient, and execution consistency score after each irrigation cycle. The control unit updates the mother liquor injection cycle, gating threshold combination, and partition priority based on the write-back results during the next start-up phase.

8. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The control unit first performs a fertilizer-free impedance scan and establishes a mechanical energy recovery baseline during the startup phase, then performs a low-dose wave packet trial injection and generates the first round of absorbable window. After the first round of absorbable window reaches the preset increase, it enters the steady-state fertilizer injection irrigation phase.

9. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, The control unit uses the target absorption improvement amount reaching the preset termination target value as the round termination condition during the steady state phase, and constrains the upper limit of mother liquor concentration, the upper limit of fertilizer injection pulse frequency, the upper limit of return liquid reuse ratio, and the water hammer risk boundary throughout the process.

10. The integrated water and fertilizer irrigation system according to claim 1, characterized in that, During the abnormal phase, the control unit executes a graded strategy in sequence according to the following steps: pressure over-limit handling, mechanical signature abnormal handling, sensor disconnection handling, and insufficient power supply handling. Pressure over-limit handling triggers pure water pressure stabilization, mechanical signature abnormal handling triggers local backflush retesting, sensor disconnection handling triggers mechanical signature weight increase and pressure reduction of fertilizer injection limit, and insufficient power supply handling triggers low power protection and unlocks in segments according to the energy recovery curve.

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