A paddy field irrigation amount monitor

Abstract

The application provides a rice field irrigation quantity monitor and relates to the technical field of agricultural irrigation research and production. The control decision device of the application only uses one water level meter, and through a water supply outer ring, an infiltration inner ring, the water level meter, a water inlet pipe, a water supply pipe, a water inlet electromagnetic valve and a water supply electromagnetic valve, physical separation and independent calculation of two components of surface water storage and soil infiltration during the irrigation process are realized, and the problem of large irrigation quantity calculation error caused by ignoring rapid infiltration under the no-water layer irrigation mode is fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of agricultural irrigation research and production technology, specifically to a paddy field irrigation volume monitoring instrument. Background Technology

[0002] Rice is the crop with the largest irrigation water consumption in my country, making it crucial to improve irrigation efficiency. Since 2006, the country has been conducting research on calculating the effective utilization coefficient of irrigation water to evaluate irrigation efficiency, requiring accurate measurement of the amount of irrigation water entering paddy fields. Due to the widespread adoption of water-saving irrigation technologies for rice, the water conditions in paddy fields during irrigation can be categorized into two types:

[0003] (1) Under normal flooding conditions, there is a water layer on the field surface and the soil is saturated. When measured with a water level gauge, the water depth H0 on the field surface is greater than 0.

[0004] (2) The field surface has no water layer and is in an unsaturated state. For example, during the paddy field soaking period, the paddy field drying period, and when using controlled irrigation or alternating wet and dry irrigation modes, the lower limit of irrigation water is less than the saturated water content. When measured with a water level gauge, the water depth on the field surface H0=0.

[0005] For situation (1), the water depth change before and after irrigation can be measured by using a water level gauge or other methods to obtain the irrigation depth. Combined with the irrigated area, the irrigation water volume can be obtained. This is because under flooded conditions, the daily seepage of paddy fields is generally 1-10 mm / d, the irrigation quota (the amount of water per irrigation, usually expressed as the irrigation depth per unit area) is generally 30-80 mm, and the irrigation time lasts 30-120 minutes. Ignoring the infiltration water volume (less than 1 mm) during irrigation has little impact on the accuracy of irrigation volume calculation.

[0006] In case (2), due to the low soil moisture content, the initial infiltration rate is relatively large, and if this is not considered, the error can reach 6%-23% (Fan Junjiang et al., 2013). Current practices usually involve using soil sampling and drying or using a soil moisture meter to measure soil moisture content in layers (each 10cm layer), and then combining this with the soil saturated moisture content parameter to calculate the difference between the actual soil moisture content and the saturated moisture content as the infiltration water volume. At the same time, the water level change in the paddy field before and after irrigation is measured, and the sum of the two is taken as the net irrigation water volume.

[0007] The main problems with the method for measuring net irrigation water in paddy fields under condition (2) are: a. Although the soil sampling and drying method has high accuracy, it requires on-site soil sampling, which is labor-intensive and time-consuming, and cannot achieve automated measurement. Although the measurement using soil moisture measuring instruments (such as time domain reflectometer (TDR) and frequency reflectometer (FDR)) is quick, convenient, and highly automated, the instruments are expensive and the data is not stable enough. b. The soil sampling depth (generally the thickness of the plow pan) is greatly affected by human factors, which affects the accuracy of the infiltration water measurement. Moreover, under normal circumstances, paddy fields need to maintain a certain amount of infiltration. If the infiltration water below the plow pan is ignored, the effective utilization coefficient of irrigation water will be underestimated.

[0008] Therefore, a paddy field irrigation monitoring instrument has been provided. Summary of the Invention

[0009] To address the problems mentioned in the background art, the present invention is implemented through the following technical solution: a paddy field irrigation monitoring instrument, comprising an outer water supply loop, an inner infiltration loop, a water level gauge, an inlet pipe, a water supply pipe, an inlet solenoid valve, a water supply solenoid valve, and a control decision device; The control and decision-making device integrates a power module, a control chip, and a memory. Both the water supply outer ring and the infiltration inner ring are bottomless cylinders, with the infiltration inner ring placed inside the water supply outer ring; The outer water supply loop is connected to the external paddy fields through an inlet pipe, which is equipped with an inlet solenoid valve. The outer water supply ring and the inner infiltration ring are connected by a water supply pipe, and a water supply solenoid valve is installed on the water supply pipe. The water level gauge is fixed inside the outer ring of the water supply system to monitor changes in the water level within the outer ring. The control decision device is electrically connected to the water level gauge, the inlet solenoid valve, and the supply solenoid valve. It is used to receive and store the water level data collected by the water level gauge, and automatically switch between the normal measurement state and the irrigation measurement state according to the water level change. In the irrigation measurement state, the device controls the opening and closing sequence of the inlet solenoid valve and the supply solenoid valve and performs sequential water level measurement. By performing the water level sequence measurement in the irrigation measurement state, the device independently calculates the increase in field surface water depth and the amount of soil infiltration water, and sums the two to obtain the total irrigation volume.

[0010] Furthermore, under normal measurement conditions, the inlet solenoid valve remains open, the supply solenoid valve remains closed, and the water level gauge continuously monitors and records the water level in the outer ring of the water supply at a first preset time interval.

[0011] Furthermore, when the control decision-making device determines that the irrigation start conditions are met based on the data from the water level gauge, it switches to the irrigation measurement state. Under irrigation measurement conditions, the control decision-making device performs at least the following operations: S1. Record the initial water level of the outer water supply loop before irrigation. ; S2. Close the water inlet solenoid valve after a first preset time delay; S3. After the first stabilization period, record the first water level in the outer water supply loop. ; S4. Open the water supply solenoid valve and supply water continuously for the first time, then close it. After a second stabilization period, record the second water level in the outer water supply loop. ; S5. After the first infiltration time, record the third water level in the outer water supply loop. ; S6. Reopen the water supply solenoid valve to supply water for the second duration, then close it. After the third stabilization period, record the fourth water level in the outer water supply loop. ; S7. Open the inlet solenoid valve and record the fifth water level in the outer water supply loop. And determine that irrigation has ended.

[0012] Furthermore, the control decision-making device is configured to calculate the total irrigation volume for this irrigation based on the recorded water level data. ; Total irrigation volume Including the increase in field water depth Soil infiltration during irrigation ,Right now ; in, In the formula, This represents the initial water level of the outer ring of the water supply system before irrigation. This refers to the water level in the outer ring of the water supply system after irrigation has ended. The calculation formula is: In the formula: The area of ​​the inner circle of the outer ring of the water supply system; The area of ​​the inner circle of the infiltration ring; The area of ​​the outer circle of the infiltration inner ring; The water level in the outer ring of the water supply system is measured after the inlet solenoid valve is closed and the water level has stabilized. The water level in the outer water supply ring is measured after the initial water supply to the inner infiltration ring and the water level has stabilized. The water level in the outer ring of the water supply system was measured after the first infiltration time. The water level in the outer water supply ring is measured after the water is supplied to the inner infiltration ring again and stabilized.

[0013] Furthermore, when determining the initial water level at the start of irrigation... When the value is greater than 0, the control decision device sets the infiltration water volume. It is zero.

[0014] Furthermore, the first preset time interval under normal measurement conditions is 15 to 30 minutes.

[0015] Furthermore, the irrigation commencement condition is that two consecutive water level changes detected by the water level gauge exceed a first preset threshold; and / or The irrigation is terminated when two consecutive water level changes detected by the water level gauge are less than the second set threshold.

[0016] Furthermore, the first threshold is set to 5-10 mm, and the second threshold is set to 2-5 mm.

[0017] Furthermore, the first preset duration is 15 minutes, the first water supply duration and the second water supply duration are 60 seconds, the first stable duration, the second stable duration and the third stable duration are 10-15 seconds, and the first infiltration duration is 15-30 minutes.

[0018] Furthermore, it also includes attitude sensors installed on the outer water supply loop or control decision-making device to monitor the installation tilt angle of the outer water supply loop in the field; The control decision device is connected to the attitude sensor and configured to: correct the original water level value measured by the water level gauge in real time according to the tilt angle, so as to eliminate the error in total irrigation volume caused by uneven installation surface or soil settlement.

[0019] Beneficial effects The present invention has the following beneficial effects: (1) The control decision device of the present invention uses only one water level gauge. Through the water supply outer ring, infiltration inner ring, water level gauge, water inlet pipe, water supply pipe, water inlet solenoid valve and water supply solenoid valve, it realizes the physical separation and independent calculation of the two components of surface water storage and soil infiltration during the irrigation process. It fundamentally solves the problem of large error in irrigation volume calculation caused by ignoring rapid infiltration in the waterless irrigation mode.

[0020] (2) When the present invention is installed in the paddy field, it is first adjusted to be level, so that the upper edge of the water supply outer ring is as horizontal as possible. In this state, the control decision device reads the output signal of the attitude sensor and records it as the horizontal reference value. This step ensures that the control decision device establishes an accurate reference. In subsequent long-term operation, the control decision device reads the real-time data of the attitude sensor at fixed intervals to obtain a signal containing the tilt direction and tilt angle. When the tilt angle is detected to be greater than a small threshold, the control decision device determines that the installation attitude has changed and water level correction is required.

[0021] (3) This invention achieves separate calculation of the increase in field surface water depth and the amount of soil infiltration water through the coordinated operation of the outer water supply ring, the inner infiltration ring, the water level gauge, the inlet pipe, the supply pipe, the inlet solenoid valve, the supply solenoid valve, and the control decision device. At the same time, the installation attitude of the outer water supply ring is monitored by the added attitude sensor, and the water level gauge measurement value is corrected in real time by the control decision device. The combination of these two aspects ensures that the total irrigation volume calculation result eliminates the principle error caused by ignoring infiltration and the benchmark error caused by installation tilt, thereby significantly improving the comprehensive accuracy of its long-term measurement.

[0022] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0024] Figure 2 This is a top view of the entire invention.

[0025] In the diagram: 1. Outer water supply ring; 2. Infiltration inner ring; 3. Water level gauge; 4. Inlet pipe; 5. Water supply pipe; 6. Inlet solenoid valve; 7. Water supply solenoid valve; and 8. Control and decision device. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0027] Please see Figures 1 to 2 The present invention provides a technical solution: a paddy field irrigation monitoring instrument, including an outer water supply ring 1, an inner infiltration ring 2, a water level gauge 3, an inlet pipe 4, a water supply pipe 5, an inlet solenoid valve 6, a water supply solenoid valve 7, and a control decision device 8. The control and decision-making device 8 integrates a power module, a control chip, and a memory; Both the water supply outer ring 1 and the infiltration inner ring 2 are bottomless cylinders, and the infiltration inner ring 2 is placed inside the water supply outer ring 1; The outer water supply ring 1 is connected to the external paddy field through the water inlet pipe 4, and the water inlet pipe 4 is equipped with a water inlet solenoid valve 6. The outer water supply ring 1 and the inner infiltration ring 2 are connected by a water supply pipe 5, and a water supply solenoid valve 7 is installed on the water supply pipe 5. The water level gauge 3 is fixed inside the water supply outer ring 1 and is used to monitor the water level changes within the water supply outer ring 1; The control decision device 8 is electrically connected to the water level gauge 3, the inlet solenoid valve 6, and the supply solenoid valve 7. It is used to receive and store the water level data collected by the water level gauge 3, and automatically switch between the normal measurement state and the irrigation measurement state according to the water level change. In the irrigation measurement state, the device controls the opening and closing sequence of the inlet solenoid valve 6 and the supply solenoid valve 7 and performs sequential water level measurement. By performing the water level sequence measurement in the irrigation measurement state, the incremental water depth on the field surface and the amount of water infiltrated into the soil are calculated independently. The total irrigation volume is obtained by summing the two.

[0028] In practical implementation, the control decision device 8 continuously receives and stores water level data sent by the water level gauge 3. By analyzing the trend of water level changes, it automatically determines and switches between the "routine measurement" and "irrigation measurement" working states of the control decision device 8. When entering the "irrigation measurement state," the control decision device 8 sends precise opening and closing commands to the two solenoid valves according to a preset sequence, forming a specific "opening and closing sequence." At multiple key time points in this sequence, the water level gauge 3 is triggered to perform measurements, thereby obtaining a set of ordered water level data. , , , , , Based on water level data and the known geometric area of ​​the ring, the control decision device 8 can calculate the "increase in field water depth" directly reflected by the water level and the "soil infiltration volume" derived from the water balance. By adding the two together, the "total irrigation volume" is obtained, which excludes the influence of instantaneous soil infiltration.

[0029] The control decision device 8 uses only one water level gauge 3. Through the water supply outer loop 1, infiltration inner loop 2, water level gauge 3, water inlet pipe 4, water supply pipe 5, water inlet solenoid valve 6, and water supply solenoid valve 7, it realizes the physical separation and independent calculation of the two components of surface water storage and soil infiltration during the irrigation process. This fundamentally solves the problem of large errors in irrigation volume calculation caused by ignoring rapid infiltration in the waterless irrigation mode.

[0030] Furthermore, under normal measurement conditions, the inlet solenoid valve 6 remains open, the supply solenoid valve 7 remains closed, and the water level gauge 3 continuously monitors and records the water level in the outer water supply loop 1 at a first preset time interval.

[0031] In practical implementation, under normal measurement conditions, the control decision device 8 sends a command to the inlet solenoid valve 6 to remain open and a command to the supply solenoid valve 7 to remain closed. At this time, the water inside the outer water supply loop 1 is freely connected to the water in the external paddy field through the open inlet pipe 4, and the water levels of the two remain completely consistent. Under the scheduling of the control decision device 8, the water level gauge 3 automatically measures the water level in the outer water supply loop 1 at fixed time intervals (e.g., every 20 minutes) and transmits the measurement data from the water level gauge 3 to the control decision device 8 in real time for recording and storage.

[0032] Operating with extremely low power consumption during non-irrigation periods, it continuously and automatically monitors the basic status of field water depth to accurately determine the start time of irrigation and record the initial water level. It provides a reliable data foundation.

[0033] Furthermore, when the control decision device 8 determines that the irrigation start conditions are met based on the data from the water level gauge 3, it switches to the irrigation measurement state. Under irrigation measurement conditions, the control decision device 8 performs at least the following operations: S1. Record the initial water level of the outer water supply ring 1 before irrigation. ; S2. After a first preset time delay, close the water inlet solenoid valve 6. S3. After the first stabilization period, record the first water level of the outer water supply loop 1. ; S4. Open the water supply solenoid valve 7 and supply water continuously for the first time, then close it. After the second stabilization period, record the second water level of the outer water supply loop 1. ; S5. After the first infiltration time, record the third water level of the outer water supply loop 1. ; S6. Reopen the water supply solenoid valve 7 and continue supplying water for the second time, then close it. After the third stabilization period, record the fourth water level in the outer water supply loop 1. ; S7. Open the inlet solenoid valve 6 and record the fifth water level in the outer water supply loop 1. And determine that irrigation has ended.

[0034] In specific implementation, the judgment logic and subsequent specific operation process for switching from "normal measurement state" to "irrigation measurement state" are as follows: The control decision device 8 analyzes the two consecutive measurement values ​​reported by the water level gauge 3 in real time. When it finds that the difference exceeds the preset threshold (e.g., 8 mm), it determines that an irrigation event has started.

[0035] The control decision-making device 8 immediately switches to irrigation measurement mode and performs the following operations in sequence: S1. Record the last measured water level value before the state switch as the initial water level for this irrigation. .

[0036] S2. Wait for a preset time (e.g., 15 minutes) to ensure that there is sufficient water in the outer water supply loop (1), and then issue a command to close the water inlet solenoid valve 6.

[0037] S3. After closing the inlet solenoid valve 6, wait for a short period of stabilization (e.g., 15 seconds). Once the water level fluctuations within the loop have subsided, trigger the level gauge 3 to measure and record the water level value at this time, which will be used as the first water level. .

[0038] S4. Issue a command to open the water supply solenoid valve 7, and then close it after a period of time (e.g., 60 seconds), allowing water in the outer water supply ring 1 to flow into the infiltration inner ring 2. After waiting for it to stabilize again (e.g., 15 seconds), trigger the water level gauge 3 to measure and record the second water level. .

[0039] S5. Allow the control decision device 8 to stand for a period of infiltration time (e.g., 30 minutes), then trigger the water level gauge 3 to measure and record the third water level. .

[0040] S6. Issue another command to open the water supply solenoid valve 7 for a period of time (e.g., 60 seconds) and then close it. After the water level is balanced, trigger the water level gauge 3 to measure and record the fourth water level. .

[0041] S7. Finally, issue a command to reopen the inlet solenoid valve 6, restoring the water level of the outer water supply loop 1 to match the water level of the external paddy field, and continuously monitor the water level. When the change in two consecutive water level measurements is less than a termination threshold (e.g., 3 mm), the irrigation is considered complete, and the final water level at this point is recorded. .

[0042] Furthermore, the control decision-making device 8 is configured to calculate the total irrigation volume for this irrigation based on the recorded water level data. ; Total irrigation volume Including the increase in field water depth Soil infiltration during irrigation ,Right now ; in, In the formula, The initial water level of the outer water supply ring 1 before irrigation. This refers to the water level in the outer ring 1 of the water supply system after irrigation is completed. The calculation formula is: In the formula: Let be the area of ​​the inner circle of the outer water supply ring 1; Let be the inner circle area of ​​the infiltration inner ring 2; The area of ​​the outer circle of the infiltration inner ring 2; The water level in the outer water supply loop 1, i.e. the first water level, is measured after the inlet solenoid valve 6 is closed and stabilized. The water level of the outer water supply ring 1, i.e., the second water level, is measured after the water is initially supplied to the inner infiltration ring 2 and stabilized. The third water level is the water level of the outer ring 1 of the water supply system, measured after the first infiltration time. The water level in the outer water supply ring 1, i.e., the fourth water level, is measured after water is supplied to the inner infiltration ring 2 again and stabilized.

[0043] In practice, S1. Under normal measurement conditions, water level gauge 3 records the water depth of the field surface within the water supply loop every 15-30 minutes.

[0044] If a rise in water level is measured, that is hour, The current water level, The irrigation (or rainfall) begins based on the previous water level, and the irrigation volume monitoring instrument is activated, entering irrigation measurement mode. At this time, the previous water level (the last water level before irrigation) is set as the initial water level. .

[0045] Under the same growth and meteorological conditions, the infiltration inner ring and the water supply outer ring are in the same state, at which point the initial water level of the infiltration inner ring is... In an unsaturated state .

[0046] If observed If the situation is determined to be flooding, proceed directly to step 6.

[0047] S2. The inlet solenoid valve closes after a 15-minute delay, allowing sufficient water to enter and raising the water level in the outer supply ring. At this time, the infiltration inner ring is not connected to the outer supply ring, maintaining the initial water level. .

[0048] S3. Close the inlet solenoid valve for 15 seconds. After the water level in the outer ring of the water supply stabilizes, measure its water level. After opening the water supply solenoid valve to supply water to the inner infiltration ring for 60 seconds, close the inlet valve. After 10 seconds, wait for the water level in the outer water supply ring to stabilize, then start the water level gauge 3 to measure the water level in the outer water supply ring. .

[0049] Since the outer water supply ring has been filled with water for at least 15 minutes, the infiltration rate has begun to slow down. Therefore, the infiltration rate within the outer water supply ring over the next 60 seconds can be disregarded. The water supply rate from the outer water supply ring to the inner infiltration ring is then calculated as follows: In the formula: The water supply volume from the outer ring to the inner infiltration ring. The area of ​​the inner circle of the outer water supply ring 1; The area of ​​the outer circle of the infiltration inner ring 2; The water level in the outer water supply loop 1, i.e. the first water level, is measured after the inlet solenoid valve 6 is closed and stabilized. The second water level is the water level of the outer water supply ring 1 after the initial water supply to the inner infiltration ring 2 has stabilized.

[0050] In practical applications, the impact of the volume of the inlet pipe, supply pipe, and solenoid valve on the water supply can be eliminated through water level monitoring.

[0051] S4. After 15-30 minutes (this period should not be too long to prevent the water in the inner ring from disappearing when the soil is too dry; if it is too short, the accuracy of water level gauge 3 will have a significant impact on the results, and it needs to be calibrated experimentally), start water level gauge 3 to measure the water depth in the outer ring of the water supply. Then, reopen the water supply solenoid valve to supply water to the inner infiltration ring for 60 seconds, and then close the valve. After 10 seconds, wait for the internal and external water levels to balance, and then start the water level gauge 3 to measure the water depth in the outer water supply ring. .

[0052] After the initial infiltration of 15-30 minutes, the infiltration rate of the outer water supply ring further decreases. Since the infiltration of the inner and outer cylinders over 60 seconds can be disregarded, the second water supply volume of the outer water supply cylinder... In the formula: This refers to the second water supply volume for the outer water cylinder; Let be the area of ​​the inner circle of the outer water supply ring 1; The area of ​​the outer circle of the infiltration inner ring 2; The third water level is the water level of the outer ring 1 of the water supply system, measured after the first infiltration time. The water level in the outer water supply ring 1, i.e., the fourth water level, is measured after water is supplied to the inner infiltration ring 2 again and stabilized.

[0053] According to the principle of water balance, the cumulative infiltration depth of the inner infiltration ring... for: When the soil is determined to be unsaturated, take... Therefore, In the formula: This refers to the amount of soil water that infiltrates during irrigation. The water supply volume from the outer ring to the inner infiltration ring. This refers to the second water supply volume for the outer water cylinder; Let be the inner circle area of ​​the infiltration inner ring 2; The water level in the outer water supply ring 1, i.e., the fourth water level, is measured after water is supplied to the inner infiltration ring 2 again and stabilized.

[0054] S5. Open the solenoid valve of the outer water supply loop to make the water levels in the paddy field and the outer water supply loop equal, and record the water level of the outer water supply loop at this time. The apparent irrigation water volume entering the paddy field from the start of irrigation is: , Increase the water depth in the fields; To open the solenoid valve of the outer water supply loop and make the water levels in the paddy field and the outer water supply loop equal, record the water level of the outer water supply loop at this time, which is the fifth water level. This is the initial water level; ;Unsaturated state .

[0055] Water level gauge 3 continues to monitor the water level in the outer ring of the water supply system, with a monitoring interval of 15 minutes, until the difference between two water levels is less than 2 to 5 mm (depending on the accuracy setting of water level gauge 3), at which point the irrigation is considered complete. This water level is taken as... Substituting into the above formula, we get .

[0056] Because the infiltration rate in the paddy field is low in the later stages, the total irrigation volume at this time is: Open the water supply solenoid valve for 15 minutes to bring the water level in the infiltration inner ring to the same level as the paddy field, then close it. Open the water inlet solenoid valve again, and the paddy field irrigation volume monitor returns to its initial state, ending this measurement. The control decision device 8 enters normal measurement mode and continues to monitor the water level until the next irrigation occurs.

[0057] S6. If observed during irrigation This was determined to be flooding, and the infiltration rate was ignored, meaning this... .

[0058] S7. Based on meteorological observations, if the water level rise is caused by rainfall, then determine the amount of irrigation water required. .

[0059] Furthermore, when determining the initial water level at the start of irrigation... When the value is greater than 0, the control decision device 8 sets the infiltration water volume. It is zero.

[0060] In practice, when determining the start of irrigation, the control decision device 8 checks the recorded initial water level. .if A value greater than zero indicates that the paddy field is currently flooded, the soil is essentially saturated, and the infiltration rate during irrigation is extremely low. In this scenario, the infiltration rate will be directly set. The total irrigation volume is simplified to .

[0061] Furthermore, the first preset time interval under normal measurement conditions is 15 to 30 minutes.

[0062] In practice, the measurement time interval of the water level gauge 3 under normal measurement conditions is specifically set to a fixed value between 15 minutes and 30 minutes, for example, 20 minutes.

[0063] This interval strikes a good balance between ensuring timely capture of irrigation or rainfall events (avoiding the omission of short-term irrigation due to excessively long intervals) and saving power consumption of the control decision device 8 and reducing data storage, making it suitable for the needs of long-term automated monitoring of paddy fields.

[0064] Furthermore, irrigation can begin when two consecutive water level changes detected by water level gauge 3 exceed a first set threshold; and / or The irrigation is terminated when two consecutive water level changes detected by water level gauge 3 are less than the second set threshold.

[0065] In practice, the difference between two consecutive water level measurements detected by the water level gauge 3 is greater than a first set threshold (e.g., 7 mm). The "irrigation end condition" is specifically defined as: in the monitoring after the inlet solenoid valve 6 is opened, the difference between two consecutive water level measurements is less than a second set threshold (e.g., 4 mm).

[0066] By setting clear numerical thresholds, an objective and unified standard is established for determining the start and end of irrigation events, avoiding false triggers caused by slight water surface fluctuations (such as wind and waves) or minor sensor drift, and improving the accuracy and reliability of status judgment.

[0067] Furthermore, the first threshold is set to 5-10 mm, and the second threshold is set to 2-5 mm.

[0068] In practice, the first set threshold (irrigation start threshold) is set within a range of 5 mm to 10 mm. The second set threshold (irrigation end threshold) is set within a range of 2 mm to 5 mm.

[0069] A reasonable range for the threshold is provided, and users can fine-tune it within this range according to the actual field conditions (such as irrigation method and water level gauge accuracy). For example, for fields with precision irrigation and small irrigation depth each time, a smaller starting threshold (such as 5 mm) can be used to improve sensitivity; for cases where the water level gauge itself has a measurement error of ±1 mm, a larger ending threshold (such as 5 mm) can be used to ensure that recording only ends after irrigation has truly stopped.

[0070] Furthermore, the first preset duration is 15 minutes, the first water supply duration and the second water supply duration are 60 seconds, the first stable duration, the second stable duration and the third stable duration are 10-15 seconds, and the first infiltration duration is 15-30 minutes.

[0071] In specific implementation, the time parameters for each segment under irrigation measurement status are specifically set as follows: the "first preset duration" (delayed closing time of the inlet valve) in step S2 is 15 minutes; the "first water supply duration" and "second water supply duration" (time to supply water to the inner loop) in steps S4 and S6 are both 60 seconds; the "first stabilization duration", "second stabilization duration" and "third stabilization duration" (time to wait for the water level to stabilize after the valve is closed) mentioned in steps S3, S4 and S5 are all 10 to 15 seconds; and the "first infiltration duration" (static infiltration time) in step S5 is 30 minutes.

[0072] Validated and specific timing parameters were provided for the valve-controlled sequence, ensuring operational feasibility and result repeatability. For example, a 15-minute delayed closure ensures sufficient water in the outer loop for subsequent supply to the inner loop; a 60-second supply time is sufficient to establish effective water exchange between the two loops; a 10-15 second settling time allows the surface oscillations caused by valve closure to subside, ensuring accurate water level gauge readings; and a 30-minute infiltration time allows the soil to complete the main rapid infiltration process, ensuring accurate measured water level readings. and The value is representative.

[0073] Furthermore, it also includes an attitude sensor installed on the water supply outer ring 1 or the control decision device 8, used to monitor the installation tilt angle of the water supply outer ring 1 in the field; The control decision device 8 is connected to the attitude sensor and is configured to: correct the original water level value measured by the water level gauge 3 in real time according to the tilt angle, so as to eliminate the error in total irrigation volume caused by uneven installation surface or soil settlement.

[0074] In practical implementation, when installing it in the paddy field, the first step is to adjust the level so that the upper edge of the water supply outer ring 1 is as horizontal as possible. In this state, the control decision device 8 reads the output signal of the attitude sensor and records it as the "horizontal reference value" (i.e., zero-position deflection angle). This step ensures that the control decision device 8 establishes an accurate reference benchmark.

[0075] During subsequent long-term operation, the control decision device 8 reads the real-time data from the attitude sensor at fixed intervals (e.g., before each water level gauge measurement) to obtain a signal containing the tilt direction and tilt angle. When the tilt angle θ (in degrees or radians) is detected to be greater than a small threshold (e.g., 0.5°), the control decision device 8 determines that the installation attitude has changed and water level correction is required.

[0076] The water level gauge 3 measures the vertical distance from its probe to the water surface. When the outer water supply ring 1 tilts, the water level inside the cylinder remains horizontal, but the mounting axis of the water level gauge 3 tilts accordingly, causing the measured length to change. The (raw reading) is not the actual water depth. .

[0077] Assume the outer water supply loop 1 is tilted at an angle θ in a certain direction. Based on geometric relationships, the actual water depth... Original reading of water level gauge 3 The relationship is:

[0078] Therefore, the correction formula is: in: This is the corrected actual water level value.

[0079] This is the raw value directly measured by water level gauge 3.

[0080] This is the absolute value of the tilt angle of the water supply outer ring 1 axis relative to the vertical direction, as measured by the attitude sensor.

[0081] After each command requiring water level measurement is triggered, the control decision device 8 executes the following sequence: Synchronously read the current tilt angle from the attitude sensor. .

[0082] Trigger water level gauge 3 to measure and obtain the raw reading. .

[0083] Determine if θ is greater than a set threshold (e.g., 0.5°). If not, then let... If so, then substitute it into the formula. Perform the calculation.

[0084] All subsequent calculations and analyses (such as determining the start of irrigation, recording) to ,calculate and The "water level value" used in ) should be replaced with this value.

Claims

1. A paddy field irrigation water monitoring instrument, characterized in that: It includes an outer water supply ring (1), an inner infiltration ring (2), a water level gauge (3), an inlet pipe (4), a water supply pipe (5), an inlet solenoid valve (6), a water supply solenoid valve (7), and a control decision device (8). The control decision device (8) integrates a power module, a control chip and a memory; Both the water supply outer ring (1) and the infiltration inner ring (2) are bottomless cylinders, and the infiltration inner ring (2) is placed inside the water supply outer ring (1); The water supply outer ring (1) is connected to the external paddy field through the water inlet pipe (4), and the water inlet pipe (4) is equipped with the water inlet solenoid valve (6). The water supply outer ring (1) and the infiltration inner ring (2) are connected through the water supply pipe (5), and the water supply solenoid valve (7) is provided on the water supply pipe (5). The water level gauge (3) is fixed inside the water supply outer ring (1) and is used to monitor the water level changes inside the water supply outer ring (1); The control decision device (8) is electrically connected to the water level gauge (3), the inlet solenoid valve (6), and the supply solenoid valve (7). It is used to receive and store the water level data collected by the water level gauge (3), and automatically switch between the normal measurement state and the irrigation measurement state according to the water level change. In the irrigation measurement state, the water level is measured sequentially by controlling the opening and closing sequence of the inlet solenoid valve (6) and the supply solenoid valve (7). By performing the water level sequence measurement in the irrigation measurement state, the increase in field surface water depth and the amount of soil infiltration water are calculated independently, and the total irrigation amount is obtained by summing the two.

2. The paddy field irrigation monitoring instrument according to claim 1, characterized in that: Under normal measurement conditions, the inlet solenoid valve (6) remains open, the supply solenoid valve (7) remains closed, and the water level gauge (3) continuously monitors and records the water level in the outer ring (1) of the water supply at a first preset time interval.

3. The paddy field irrigation monitoring instrument according to claim 2, characterized in that: When the control decision device (8) determines that the irrigation start conditions are met based on the data from the water level gauge (3), it switches to the irrigation measurement state. Under irrigation measurement conditions, the control decision device (8) performs at least the following operations: S1. Record the initial water level of the outer water supply loop (1) before irrigation. ; S2. After a first preset time delay, the water inlet solenoid valve (6) is closed. S3. After the first stable period, record the first water level of the outer water supply loop (1). ; S4. Open the water supply solenoid valve (7) for a first water supply duration, then close it. After a second stable duration, record the second water level of the outer water supply loop (1). ; S5. After the first infiltration time, record the third water level of the outer water supply ring (1). ; S6. Reopen the water supply solenoid valve (7) for a second water supply duration, then close it. After a third stable duration, record the fourth water level of the outer water supply loop (1). ; S7. Open the inlet solenoid valve (6) and record the fifth water level of the outer water supply loop (1). And determine that irrigation has ended.

4. The paddy field irrigation monitoring instrument according to claim 3, characterized in that: The control decision device (8) is configured to calculate the total irrigation volume for this irrigation based on the recorded water level data. ; The total irrigation volume Including the increase in field water depth Soil infiltration during irrigation ,Right now ; in, In the formula, The initial water level of the outer water supply ring (1) before irrigation. The water level of the outer water supply ring (1) after irrigation is completed; The calculation formula is: In the formula: The inner circle area of ​​the water supply outer ring (1); The inner circle area of ​​the infiltration inner ring (2); The outer circumference of the infiltration inner ring (2); The water level of the outer water supply ring (1) is measured after the water inlet solenoid valve (6) is closed and stabilized; The water level of the water supply outer ring (1) is measured after the water is first supplied to the infiltration inner ring (2) and stabilized. The water level of the outer water supply ring (1) is measured after the first infiltration time; The water level of the water supply outer ring (1) is measured after water is supplied to the infiltration inner ring (2) again and stabilized.

5. A paddy field irrigation monitoring instrument according to claim 4, characterized in that: When determining the initial water level at the start of irrigation When the value is greater than 0, the control decision device (8) sets the infiltration water volume. It is zero.

6. The paddy field irrigation monitoring instrument according to claim 2, characterized in that: The first preset time interval under the normal measurement state is 15 to 30 minutes.

7. A paddy field irrigation monitoring instrument according to claim 3, characterized in that: The irrigation start condition is that two consecutive water level changes monitored by the water level gauge (3) are greater than a first set threshold; and / or The condition for determining the end of irrigation is that the water level changes detected by the water level gauge (3) are less than the second set threshold for two consecutive times.

8. A paddy field irrigation monitoring instrument according to claim 7, characterized in that: The first set threshold is 5-10 mm, and the second set threshold is 2-5 mm.

9. A paddy field irrigation monitoring instrument according to claim 3, characterized in that: The first preset duration is 15 minutes, the first water supply duration and the second water supply duration are 60 seconds, the first stable duration, the second stable duration and the third stable duration are 10-15 seconds, and the first infiltration duration is 15-30 minutes.

10. A paddy field irrigation monitoring instrument according to any one of claims 3 to 9, characterized in that: It also includes an attitude sensor installed on the water supply outer ring (1) or the control decision device (8) for monitoring the installation tilt angle of the water supply outer ring (1) in the field; The control decision device (8) is connected to the attitude sensor and is configured to: correct the original water level value measured by the water level gauge (3) in real time according to the tilt angle, so as to eliminate the error in total irrigation volume caused by uneven installation surface or soil settlement.

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