A water and fertilizer intelligent control method and system based on multi-factor decision-making

Abstract

The present invention discloses a method and system for intelligent water and fertilizer control based on multi-factor decision-making. A new rhizosphere environment control strategy is added to the original automatic rotation irrigation system. The scheme uses the data collected by the sensor as input, and updates the parameters and strategies at the next irrigation through data processing and analysis. This feedback mechanism based on real-time data enables the system to respond to changes in the rhizosphere environment of blueberries in a timely manner, dynamically adjust the working parameters of the irrigation system, thereby meeting the growth conditions of blueberries, keeping the growth environment in the best state, and having the ability of adaptive adjustment to ensure the improvement of yield and quality. Frequent manual intervention is no longer required, which greatly reduces the workload and improves work efficiency. In addition, the present invention has demonstration and promotion significance for agricultural production practice, provides useful experience for the irrigation of other crops, can promote the popularization and promotion of modern intelligent agricultural technology, and promote the modernization of agricultural production.

Description

Technical Field

[0001] The present invention belongs to the technical field of agricultural Internet of Things, and in particular relates to a water and fertilizer intelligent control method and system based on multi-factor decision-making. Background Art

[0002] In blueberry matrix cultivation, the integrated water and fertilizer intelligent irrigation equipment sets the target EC (electrical conductivity) and PH (acidity) values ​​on the control interface. During operation, it can detect the EC and PH of the output water and fertilizer solution in real time. Based on these data, the control unit can adjust the EC and PH of the output water and fertilizer solution in real time, and supply water and fertilizer at a fixed time or in a fixed quantity, so as to save water, fertilizer and labor, and improve the yield and quality of blueberries.

[0003] The integrated water and fertilizer machines currently on the market can detect and regulate the EC and pH of the output water and fertilizer solution in real time. However, the growth consumption and transpiration of blueberries will affect the EC and pH of the rhizosphere environment of blueberries. The EC and pH of the rhizosphere of blueberries have a large lag and an uncertain correlation with the EC and pH of the water and fertilizer solution output by the integrated water and fertilizer machine. To regulate the EC and pH of the rhizosphere environment of blueberries, it is necessary to constantly reset the integrated water and fertilizer machine manually based on the EC and pH detection of the rhizosphere environment, which is a waste of time and has low accuracy, resulting in large fluctuations in the EC and pH of the rhizosphere of blueberries, thus affecting the growth and quality of blueberries. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a water and fertilizer intelligent control method and system based on multi-factor decision-making. According to multiple important factors closely related to blueberry growth (including the EC value, pH value of the blueberry root system, and the humidity of the substrate), the water and fertilizer required for blueberries under different environmental conditions are decided on the control core of the water-fertilizer integrated equipment, thereby realizing precise and intelligent regulation of fertilization and irrigation of blueberry crops, without the need for frequent manual readjustment of relevant settings.

[0005] The technical solution provided by the present invention is as follows:

[0006] A water and fertilizer intelligent control method based on multi-factor decision-making includes the following steps:

[0007] S1. Configuring water and fertilizer for timed rotation irrigation of blueberries: each water and fertilizer mother liquid is introduced into the mixing pipe through a liquid infusion pipeline with the same pipe diameter and liquid flow rate, and a solenoid valve for controlling the switch of the pipeline is arranged on the liquid infusion pipeline; the water and fertilizer are configured by controlling the switch cycle of the solenoid valve on the corresponding liquid infusion pipeline during the fertilizer mixing cycle according to the ratio of each water and fertilizer mother liquid;

[0008] S2. Automatically regulate the frequency converter rate according to the target EC value of the water and fertilizer and the measured EC value of the water and fertilizer at the liquid outlet of the mixing pipe. The frequency converter is used to control the rate at which the fertilizer pump sucks the water and fertilizer from the liquid outlet of the mixing pipe;

[0009] S3. According to the target pH value of the water and fertilizer and the measured pH value of the water and fertilizer at the liquid outlet of the mixing pipe, regulate the pH value of the water and fertilizer by controlling the switching cycle of the solenoid valve connected to the acid barrel. The solenoid valve connected to the acid barrel is used to control the opening and closing of the acid barrel, and the acid barrel is used to inject the pH adjustment liquid into the mixing pipe;

[0010] The target EC value and target pH value are manually set during initialization, and after each timed round-robin irrigation ends, they are automatically adjusted according to the measured EC value and pH value of the blueberry roots; the irrigation duration for each timed round-robin irrigation is manually set during initialization, and after each timed round-robin irrigation ends, it is automatically adjusted according to the measured soil moisture value and required value of the blueberry roots.

[0011] Further, in step S1, when the prepared water and fertilizer only contains one type of water and fertilizer mother liquor, keep the solenoid valve controlling the output of this water and fertilizer mother liquor open during the specified fertilizer preparation time; when the prepared water and fertilizer only contains two types of mother liquors, mother liquor A and mother liquor B, and the ratio is a:b: If a > b, set the switching cycle Ta of the solenoid valve corresponding to mother liquor A to be the same as the fertilizer preparation cycle T, and set the switching cycle Tb of the solenoid valve corresponding to mother liquor B to be Ta * b / a; if a = b, then Ta = Tb = T; if a < b, then Tb = T, Ta = Tb * a / b.

[0012] Further, in step S1, when the prepared water and fertilizer only contains three types of mother liquors, mother liquor A, mother liquor B, and mother liquor C, and the ratio is a:b:c, then set the corresponding solenoid valve switching cycles Ta, Tb, and Tc respectively as: Ta = T * a / (a + b + c), Tb = T * b / (a + b + c), Tc = T * c / (a + b + c); if the solenoid valve switching cycle is t, it means that within the fertilizer preparation cycle T, the opening time of this solenoid valve is t, and the closing time is T - t.

[0013] Further, in step S2, assume that the target EC value, the measured EC value at the liquid outlet of the mixing pipe, the EC upper limit value, the EC lower limit value, and the deviation percentage are respectively represented as

[0014] EC 目标 、EC 出液口 、EC 上限 、EC 下限 、X, and there is EC 上限 >EC 目标 *(1 + X) > EC 目标 >EC 目标 *(1 - X) > EC 下限 , then:

[0015] If EC 出液口 >EC 上限 , the alarm is triggered immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working;

[0016] If EC 上限 >EC 出液口 >EC 目标 *(1+X), reduce the inverter speed by 5%;

[0017] If EC 目标 *(1+X)>EC 出液口 >EC 目标 *(1-X), the inverter speed remains unchanged;

[0018] If EC 出液口 <EC 目标 *(1-X), increase the inverter speed by 5%;

[0019] If EC 出液口 <EC 下限 , the alarm is sounded immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working.

[0020] Further, in step S3, it is assumed that the pH target value, the pH measured value at the outlet of the mixing tube, the pH upper limit value, the pH lower limit value and the deviation percentage are respectively expressed as

[0021] PH 目标 , PH 出液口 , PH 上限 , PH 下限 , X, and PH 上限 >PH 目标 *(1+X)>PH 目标 >PH 目标 *(1-X)>PH 下限 ,but:

[0022] If PH 出液口 >PH 上限 , the alarm is triggered immediately, the solenoid valve connected to the acid barrel is closed, and the inverter and fertilizer pump stop working;

[0023] If PH 上限 >PH 出液口 >PH 目标 *(1+X), reduce the switching cycle of the solenoid valve connected to the acid barrel;

[0024] If PH 目标 *(1+X)>PH 出液口 >PH 目标 *(1-X), keep the switch cycle of the solenoid valve connected to the acid barrel unchanged;

[0025] If PH出液口 <PH 目标 *(1-X), increase the switching cycle of the solenoid valve connected to the acid barrel;

[0026] If PH 出液口 <PH 下限 , the alarm is sounded immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working.

[0027] Furthermore, it is assumed that the EC target value and the measured EC value of the blueberry root system are expressed as EC 目标 and EC 实测 :

[0028] If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <EC 目标 ,

[0029] Then let EC 目标 =EC 实测 +(EC 目标 -EC 实测 )*50%;

[0030] If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 >EC 目标 ,

[0031] Then let EC 目标 =EC 实测 -(EC 实测 -EC 目标 )*50%;

[0032] If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 =EC 目标 , then keep EC 目标 constant.

[0033] Furthermore, it is assumed that the pH target value and the pH measured value of the blueberry root system are expressed as pH 目标 and PH 实测 :

[0034] If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <PH 目标 ,

[0035] Then let PH 目标 =PH 实测 +(PH 目标 -PH 实测 )*25%;

[0036] If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 >PH目标 ,

[0037] Then let PH 目标 =PH 实测 -(PH 实测 -PH 目标 )*25%;

[0038] If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 =PH 目标 , then maintain pH 目标 constant.

[0039] Furthermore, it is assumed that the set value of irrigation time, the measured value of soil moisture of blueberry root system and the required value are T 设定 RH 实测 RH 目标 If RH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <RH 目标 , then let T 设定 =T 设定 *110%; if RH 实测 >RH 目标 , then let T 设定 =T 设定 *90%; if RH 实测 =RH 目标 , then keep T 设定 The value remains unchanged.

[0040] A water and fertilizer intelligent control system based on the above method comprises:

[0041] A plurality of water-fertilizer mother liquid storage containers are respectively connected to the mixing pipe through the infusion pipeline, and the infusion pipeline is provided with a solenoid valve for controlling the pipeline switch; the mixing pipe is also connected to an acid barrel for storing pH regulating liquid, and the acid barrel is provided with an acid barrel connection solenoid valve for controlling the acid barrel switch; the liquid outlet of the mixing pipe is connected to a fertilizer pump, and the fertilizer pump is also provided with a frequency converter for controlling the fertilizer suction rate of the fertilizer pump;

[0042] It also includes an EC sensor and a PH sensor for detecting the EC value and PH value of water and fertilizer at the outlet of the mixing pipe, and an EC sensor, a PH sensor and a RH sensor for detecting the EC value, PH value and soil moisture of the rhizosphere of blueberries;

[0043] Each solenoid valve, acid barrel connection solenoid, fertilizer pump, frequency converter and sensor are connected to the control module;

[0044] The control module is used to control the switching state of the solenoid valve on the corresponding infusion pipeline during the fertilizer mixing cycle according to the ratio of each water-fertilizer mother solution, and is also used to control the inverter speed according to the water-fertilizer EC target value and the water-fertilizer EC measured value at the mixing pipe outlet. It is also used to control the switching state of the solenoid valve connected to the acid barrel according to the water-fertilizer PH target value and the water-fertilizer PH measured value at the mixing pipe outlet, and is also used to adjust the water-fertilizer EC target value, PH target value, and the irrigation duration of each time of the timed rotation irrigation according to the EC measured value, PH measured value, and soil moisture measured value of the blueberry root system.

[0045] Furthermore, the control module is also provided with an input setting module for initializing the water-fertilizer EC target value, the PH target value, the irrigation duration of each time-controlled rotation irrigation, the ratio of the water-fertilizer mother solution and related parameter values.

[0046] Beneficial effects of the present invention:

[0047] Traditional automatic irrigation systems can often only work according to preset fixed parameters and cannot automatically adapt to changes in the environment. The present invention adds a new rhizosphere environment regulation strategy to the original automatic irrigation system. The scheme uses the data collected by the sensor as input, and updates the parameters and strategies at the next irrigation through data processing and analysis. This feedback mechanism based on real-time data enables the system to respond to changes in the rhizosphere environment of blueberries in a timely manner and dynamically adjust the working parameters of the irrigation system to meet the growth conditions of blueberries and keep the growth environment in the best state. It has the ability of adaptive regulation to ensure the improvement of yield and quality. Frequent manual intervention is no longer required, which greatly reduces the workload and improves work efficiency. In addition, the present invention has demonstration and promotion significance for agricultural production practice, provides useful experience for the irrigation of other crops, can promote the popularization and promotion of modern intelligent agricultural technology, and promote the modernization of agricultural production. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0049] Figure 1 Schematic diagram of the EC value detection and control strategy of the liquid outlet of the mixing tube provided by one embodiment of the present invention;

[0050] Figure 2 It is a schematic diagram of a pH value detection and control strategy for a liquid outlet of a mixing tube provided by an embodiment of the present invention;

[0051] Figure 3 is a schematic diagram of an environmental strategy framework provided by an embodiment of the present invention;

[0052] Figure 4This is a schematic diagram of EC value decision-making and regulation of the blueberry rhizosphere provided by an embodiment of the present invention;

[0053] Figure 5 This is a schematic diagram of pH value decision-making and regulation of the blueberry rhizosphere provided by an embodiment of the present invention;

[0054] Figure 6 This is a schematic diagram of decision-making and regulation of the EH value of the blueberry rhizosphere provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the present invention.

[0056] The present embodiment provides an intelligent water and fertilizer control method based on multi-factor decision-making, which is mainly composed of an automatic timed rotation irrigation mechanism and an environmental strategy. Before each irrigation and fertilization, the blueberry rhizosphere environment is first detected by a sensor, and then a corresponding environmental strategy is generated to intelligently and automatically adjust the originally set automatic timed rotation irrigation.

[0057] The automatic timed irrigation mechanism mainly involves three control strategies: Venturi tube fertilizer absorption ratio control strategy, mixing tube outlet EC value detection and control strategy and mixing tube outlet pH value detection and control strategy.

[0058] 1.1. Venturi tube fertilizer suction ratio control strategy

[0059] When the water-fertilizer to be prepared contains only one kind of water-fertilizer mother liquid (taking only mother liquid A as an example), there is no need to set the ratio. It is only necessary to keep the A-way solenoid valve that controls the output of mother liquid A normally open during the specified fertilizer preparation time.

[0060] When the water-fertilizer mix contains two kinds of water-fertilizer mother liquors (taking mother liquor A and mother liquor B as an example), it is necessary to design the ratio configuration of mother liquor A and mother liquor B. The ratio configuration logic is as follows:

[0061] First, set the ratio of mother liquid A to mother liquid B as a:b (a and b are both integers of 1 to 10), then set the fertilizer mixing cycle T (5 to 10s), and finally form the target water fertilizer according to the switching cycle of the pulse solenoid valve (the solenoid valve on the A circuit controls the output of mother liquid A, and its switching cycle is Ta; the solenoid valve on the B circuit controls the output of mother liquid B, and its switching cycle is Tb):

[0062] (1) If a>b, then Ta=T, Tb=Ta*b / a;

[0063] (2) If a = b, then Ta = Tb = T;

[0064] (3) If a < b, then Tb = T, Ta = Tb * a / b.

[0065] For example: Suppose a:b = 1:2, T = 6 s, then Tb = T = 6 s, Ta = Tb * a / b = 6 * 1 / 2 = 3 s. Therefore, the solenoid valve of path A opens for 3 seconds and closes for 3 seconds within one fertilization cycle, and the solenoid valve of path B opens for 6 seconds and closes for 0 seconds within one fertilization cycle. The Venturi tubes in the pipelines where the solenoid valves of path A and path B are located have the same inner diameter and the same liquid flow rate, and the fertilization cycle is continuously repeated.

[0066] When the prepared water fertilizer contains three kinds of water fertilizer mother liquors (taking the selection of mother liquors A, B, and C as an example), design the proportion configuration of mother liquors A, B, and C: First, set the ratio of the mother liquors A, B, and C as a:b:c, then set the fertilization cycle T, and finally form the target water fertilizer according to the on - off cycle of the pulse solenoid valve (the solenoid valve of path C controls the output of mother liquor C, and its on - off cycle is Tc):

[0067] (1) Ta = T * a / (a + b + c);

[0068] (2) Tb = T * b / (a + b + c);

[0069] (3) Tc = T * c / (a + b + c).

[0070] For example: Suppose a:b:c = 1:2:3, T = 6 s, then Ta = 6 * 1 / (1 + 2 + 3) = 1 s, Tb = 6 * 2 / (1 + 2 + 3) = 2 s, Tc = 6 * 3 / (1 + 2 + 3) = 3 s. Therefore, the solenoid valve of path A opens for 1 second and closes for 5 seconds within one fertilization cycle, the solenoid valve of path B opens for 2 seconds and closes for 4 seconds within one fertilization cycle, and the solenoid valve of path C opens for 3 seconds and closes for 3 seconds within one fertilization cycle. The Venturi tubes in the pipelines where the solenoid valves of path A, path B, and path C are located have the same inner diameter and the same liquid flow rate, and the fertilization cycle is continuously repeated.

[0071] 1.2. EC value detection and regulation strategy for the liquid outlet of the mixing pipe

[0072] As Figure 1 shown, the EC control scheme is as follows: Control the EC value of the mixing pipe between 0 and 4 us / cm, corresponding to the fertilizer absorption percentage of the fertilizer pump controlled by the frequency converter from 0% to 100%. Set EC 上限 , EC 下限 , EC 目标 , the deviation percentage is between 0% and 15%. Determine the mapping between the frequency converter and the error percentage, the delay time, and the full liquid level height through actual measurement. The configuration logic is as follows (EC 上限 > EC 目标*(1+% deviation)>EC 目标 >EC 目标 *(1-% deviation)>EC 下限 ):

[0073] (1) If EC 出液口 >EC 上限 , an alarm is sounded immediately, the solenoid valve is closed, and the inverter and all pumps stop working;

[0074] (2) If EC 上限 >EC 出液口 >EC 目标 *(1+deviation percentage), reduce the inverter speed by 5%;

[0075] (3) If EC 目标 *(1+% deviation)>EC 出液口 >EC 目标 *(1-deviation percentage), the inverter speed remains unchanged;

[0076] (4) If EC 出液口 <EC 目标 *(1-deviation percentage), increase the inverter speed by 5%;

[0077] (5) If EC 出液口 <EC 下限 , an alarm is sounded immediately, the solenoid valve is closed, and the inverter and all pumps stop working.

[0078] 1.3. PH value detection and control strategy at the outlet of the mixing tube

[0079] like Figure 2 As shown, the PH control scheme is as follows: Set PH 上限 , PH 下限 , PH 目标 , set the deviation percentage, the percentage range is 0% to 15%. The configuration logic is as follows (PH 上限 >PH 目标 *(1+deviation percentage)>PH 目标 >PH 目标 *(1-percent deviation)>PH 下限 ):

[0080] (1) If PH 出液口 >PH 上限 , an alarm is sounded immediately, the solenoid valve connected to the acid barrel is closed, and the inverter and all pumps stop working;

[0081] (2) If PH 上限 >PH 出液口 >PH 目标 *(1+deviation percentage), the switching cycle of the solenoid valve connected to the acid barrel decreases;

[0082] (3) If PH 目标 *(1+deviation percentage)>PH 出液口 >PH 目标 *(1-deviation percentage), the switching cycle of the solenoid valve connected to the acid barrel remains unchanged;

[0083] (4) If PH 目标 <PH 目标 *(1-deviation percentage), the switching cycle of the solenoid valve connected to the acid barrel increases;

[0084] (5) If PH 出液口 <PH 下限 , an alarm is sounded immediately, the solenoid valve is closed, and the inverter and all pumps stop working.

[0085] The key point of this scheme is to generate an environmental strategy based on the multiple decision factors that affect the growth of blueberries (i.e., the EC, pH value, and humidity of the cultivation medium in the rhizosphere of blueberries detected in the environmental strategy), such as Figure 3 As shown in the figure. Since blueberry crops require frequent fertilization and small amounts of fertilizers to be applied multiple times, the environmental strategy generated by the data detected by the blueberry rhizosphere matrix after each automatic timed irrigation is crucial. The following will introduce how to perform algorithm regulation based on the generated environmental strategy.

[0086] 2.1. EC value decision-making and regulation in the blueberry rhizosphere

[0087] In this scheme, the EC target value is manually set on the water-fertilizer machine during initialization, and after each scheduled irrigation, the system automatically adjusts it according to the actual EC value of the blueberry root system. Figure 4 As shown,

[0088] Assume that the target EC value and the measured EC value of blueberry root system are expressed as EC 目标 and EC 实测 :

[0089] (1) If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <EC 目标 ,

[0090] Then let EC 目标 =EC 实测 +(EC 目标 -EC 实测 )*50%;

[0091] (2) If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 >EC 目标 ,

[0092] Then let EC目标 =EC 实测 -(EC 实测 -EC 目标 )*50%;

[0093] (3) If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 =EC 目标 ,

[0094] Keep EC 目标 constant.

[0095] 2.2. Decision-making and regulation of pH value in the blueberry rhizosphere

[0096] In this solution, the pH target value is manually set on the water-fertilizer machine during initialization, and after each scheduled irrigation, the system automatically adjusts the pH value of the blueberry root system according to the actual pH value. Figure 5 As shown,

[0097] Assume that the pH target value and the pH measured value of the blueberry root system are expressed as pH 目标 and PH 实测 :

[0098] (1) If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <PH 目标 ,

[0099] Then let PH 目标 =PH 实测 +(PH 目标 -PH 实测 )*25%;

[0100] (2) If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation begins, 实测 >PH 目标 ,

[0101] Then let PH 目标 =PH 实测 -(PH 实测 -PH 目标 )*25%;

[0102] (3) If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 =PH 目标 ,

[0103] Keep pH 目标 constant.

[0104] 2.3. Soil moisture decision-making and regulation in the blueberry rhizosphere

[0105] The irrigation time of each scheduled irrigation is manually set during initialization, and after each scheduled irrigation, the system automatically adjusts the time based on the actual soil moisture value of the blueberry root system and the required value. Figure 6 As shown in the figure, it is assumed that the set value of irrigation time, the measured value of soil moisture of blueberry root system and the required value are T 设定 RH 实测 RH 目标 :

[0106] (1) If after the automatic timed irrigation ends and before the next automatic timed irrigation, RH 目标 >RH 实测 ,

[0107] Then T 设定 =T 设定 *110%, make corresponding adjustments;

[0108] (2) If after the automatic timed irrigation ends and before the next automatic timed irrigation, RH 目标 <RH 实测 ,

[0109] Then T 设定 =T 设定 *90%, make corresponding adjustments;

[0110] (3) If after the automatic timed irrigation ends and before the next automatic timed irrigation, RH 目标 =RH 实测 ,

[0111] Then T 设定 =T 设定 , the next time machine T 设定 The set value remains unchanged.

[0112] Based on the above content, the main steps of the water and fertilizer intelligent control method based on multi-factor decision-making provided in this embodiment can be summarized as follows:

[0113] S1. Configure water and fertilizer for timed rotation irrigation of blueberries: each water and fertilizer mother liquid is introduced into the mixing pipe through a liquid infusion pipeline with the same pipe diameter and liquid flow rate, and a solenoid valve for controlling the switch of the pipeline is provided on the liquid infusion pipeline; the water and fertilizer are configured according to the ratio of each water and fertilizer mother liquid by controlling the switch cycle of the solenoid valve on the corresponding liquid infusion pipeline during the fertilizer mixing cycle. For details, please refer to the above section 1.1.

[0114] S2. Automatically adjust the frequency converter speed according to the water-fertilizer EC target value and the water-fertilizer EC measured value at the outlet of the mixing pipe. The frequency converter is used to control the speed at which the fertilizer pump draws water and fertilizer from the outlet of the mixing pipe. For details, see Section 1.2 above.

[0115] S3. According to the target pH value of water and fertilizer and the measured pH value of water and fertilizer at the outlet of the mixing pipe, the pH value of water and fertilizer is regulated by controlling the switch cycle of the solenoid valve connected to the acid barrel, wherein the solenoid valve connected to the acid barrel is used to control the switch of the acid barrel, and the acid barrel is used to inject the pH regulating liquid into the mixing pipe. For details, see the above section 1.3.

[0116] The EC target value and the PH target value are manually set at the time of initialization, and after each timed irrigation, the system automatically adjusts the EC value and the PH value of the blueberry root system according to the actual EC value and the actual PH value of the blueberry root system. For details, see Sections 2.1 and 2.2. The irrigation time of each timed irrigation is also manually set at the time of initialization, and after each timed irrigation, the system automatically adjusts the soil moisture value and the required value of the blueberry root system according to the actual soil moisture value and the required value of the blueberry root system according to the above Section 2.3.

[0117] Based on the above method, this embodiment also provides a water and fertilizer intelligent control system, including:

[0118] A plurality of water-fertilizer mother liquid storage containers are respectively connected to the mixing pipe through the infusion pipeline, and the infusion pipeline is provided with a solenoid valve for controlling the pipeline switch; the mixing pipe is also connected to an acid barrel for storing pH regulating liquid, and the acid barrel is provided with an acid barrel connection solenoid valve for controlling the acid barrel switch; the liquid outlet of the mixing pipe is connected to a fertilizer pump, and the fertilizer pump is also provided with a frequency converter for controlling the fertilizer suction rate of the fertilizer pump;

[0119] It also includes an EC sensor and a PH sensor for detecting the EC value and PH value of water and fertilizer at the outlet of the mixing pipe, and an EC sensor, a PH sensor and a RH sensor for detecting the EC value, PH value and soil moisture of the rhizosphere of blueberries;

[0120] Each solenoid valve, acid barrel connection solenoid, fertilizer pump, frequency converter and sensor are connected to the control module;

[0121] The control module is used to control the switching state of the solenoid valve on the corresponding infusion pipeline during the fertilizer mixing cycle according to the ratio of each water-fertilizer mother solution, and is also used to control the inverter speed according to the water-fertilizer EC target value and the water-fertilizer EC measured value at the mixing pipe outlet. It is also used to control the switching state of the solenoid valve connected to the acid barrel according to the water-fertilizer PH target value and the water-fertilizer PH measured value at the mixing pipe outlet, and is also used to adjust the water-fertilizer EC target value, PH target value, and the irrigation duration of each time of the timed rotation irrigation according to the EC measured value, PH measured value, and soil moisture measured value of the blueberry root system.

[0122] In some embodiments, in order to facilitate regulation and improve the scope of application of the system, the control module is also provided with an input setting module for initializing the water and fertilizer EC target value, the PH target value, the irrigation duration of each time of the timed rotation irrigation, the ratio of the water and fertilizer mother solution and related parameter values; an alarm module can also be provided for alarming when the system is abnormal.

[0123] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A water and fertilizer intelligent control method based on multi-factor decision-making, characterized in that: It includes the following steps: S1. Configure the water and fertilizer for timed rotational irrigation of blueberries: Each mother liquor of water and fertilizer is introduced into the mixing pipe through an infusion pipeline with the same pipe diameter and liquid flow rate. An electromagnetic valve for controlling the pipeline switch is provided on the infusion pipeline. Configure the water and fertilizer by controlling the switch cycle of the electromagnetic valve on the corresponding infusion pipeline within the fertilizer preparation cycle according to the ratio of each mother liquor of water and fertilizer; S2. Automatically adjust the frequency converter speed according to the EC target value of the water and fertilizer and the measured EC value of the water and fertilizer at the liquid outlet of the mixing pipe. The frequency converter is used to control the rate at which the fertilizer pump sucks the water and fertilizer from the liquid outlet of the mixing pipe; Assume that the EC target value, the EC measured value at the outlet of the mixing tube, the EC upper limit value, the EC lower limit value and the deviation percentage are expressed as EC 目标 ,EC 出液口 ,EC 上限 ,EC 下限 , X, and EC 上限 > EC 目标 *(1+X)>EC 目标 > EC 目标 * (1-X)> EC 下限 ,but: If EC 出液口 > EC 上限 , the alarm is triggered immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working; If EC 上限 > EC 出液口 > EC 目标 *(1+X), reduce the inverter speed by 5%; If EC 目标 *(1+X)>EC 出液口 > EC 目标 *(1-X), the inverter speed remains unchanged; If EC 出液口 < EC 目标 *(1-X), increase the inverter speed by 5%; If EC 出液口 < EC 下限 , the alarm is triggered immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working; S3. According to the PH target value of the water and fertilizer and the measured PH value of the water and fertilizer at the liquid outlet of the mixing pipe, control the switch cycle of the electromagnetic valve connecting the acid barrel to adjust the PH value of the water and fertilizer. The electromagnetic valve connecting the acid barrel is used to control the switch of the acid barrel, and the acid barrel is used to inject the PH adjustment liquid into the mixing pipe; The EC target value and PH target value are manually set during initialization and automatically adjusted according to the measured EC value and PH value of the blueberry roots after each timed rotational irrigation. The irrigation duration for each timed rotational irrigation is manually set during initialization and automatically adjusted according to the measured soil moisture value and required value of the blueberry roots after each timed rotational irrigation.

2. The water and fertilizer intelligent control method according to claim 1, characterized in that: In step S1, when the prepared water and fertilizer contains only one mother liquor of water and fertilizer, keep the electromagnetic valve controlling the output of this mother liquor of water and fertilizer open during the specified fertilizer preparation time. When the prepared water and fertilizer contains only two mother liquors, mother liquor A and mother liquor B, and the ratio is a:b: If a>b, set the switch cycle Ta of the electromagnetic valve corresponding to mother liquor A to be the same as the fertilizer preparation cycle T, and set the switch cycle Tb of the electromagnetic valve corresponding to mother liquor B to be Ta*b / a; If a = b, then Ta = Tb = T; if a < b, then Tb = T, Ta = Tb*a / b.

3. The water and fertilizer intelligent control method according to claim 1, characterized in that: In step S1, when the prepared water and fertilizer contains only three mother liquors, mother liquor A, mother liquor B, and mother liquor C, and the ratio is a:b:c, then set the corresponding electromagnetic valve switch cycles Ta, Tb, and Tc respectively as: Ta = T*a / (a + b + c), Tb = T*b / (a + b + c), Tc = T*c / (a + b + c); If the electromagnetic valve switch cycle is t, it means that within the fertilizer preparation cycle T, the opening time of this electromagnetic valve is t, and the closing time is T - t.

4. The water and fertilizer intelligent control method according to claim 1, characterized in that: In step S3, assume that the PH target value, the measured PH value at the liquid outlet of the mixing pipe, the PH upper limit value, the PH lower limit value, and the deviation percentage are respectively represented as PH 目标 、PH 出液口 、PH 上限 、PH 下限 、X, and there is PH 上限 > PH 目标 *(1 + X)> PH 目标 > PH 目标 * (1 - X)> PH 下限 , then: If PH 出液口 > PH 上限 , the alarm is triggered immediately, the solenoid valve connected to the acid barrel is closed, and the inverter and fertilizer pump stop working; If PH 上限 > PH 出液口 > PH 目标 *(1+X), reduce the switching cycle of the solenoid valve connected to the acid barrel; If PH 目标 *(1+X)> PH 出液口 >PH 目标 *(1-X), keep the switch cycle of the solenoid valve connected to the acid barrel unchanged; If PH 出液口 <PH 目标 *(1-X), increase the switching cycle of the solenoid valve connected to the acid barrel; If PH 出液口 < PH 下限 , the alarm is sounded immediately, the solenoid valve is closed, and the inverter and fertilizer pump stop working.

5. The water and fertilizer intelligent control method according to claim 1, characterized in that: Assume that the target EC value and the measured EC value of blueberry root system are expressed as EC 目标 and EC 实测 : If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 <EC 目标 , Then let EC 目标 =EC 实测 + (EC 目标 -EC 实测 )*50%; If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 >EC 目标 , Then let EC 目标 =EC 实测 - (EC 实测 -EC 目标 )*50%; If EC is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 =EC 目标 , then keep EC 目标 constant.

6. The water and fertilizer intelligent control method according to claim 1, characterized in that: Assume that the pH target value and the pH measured value of the blueberry root system are expressed as pH 目标 and PH 实测 : If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 < PH 目标 , Then let PH 目标 = PH 实测 + (PH 目标 -PH 实测 )*25%; If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 > PH 目标 , Then let PH 目标 = PH 实测 - (PH 实测 -PH 目标 )*25%; If PH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 = PH 目标 , then maintain pH 目标 constant.

7. The water and fertilizer intelligent control method according to claim 1, characterized in that: Assume that the set value of irrigation time, the measured value and the required value of soil moisture of blueberry root system are T 设定 RH 实测 RH 目标 If RH is detected after the scheduled irrigation ends and before the next scheduled irrigation 实测 < RH 目标 , then let T 设定 = T 设定 *110%; if RH 实测 > RH 目标 , then let T 设定 = T 设定 *90%; if RH 实测 = RH 目标 , then keep T 设定 The value remains unchanged.

8. A water and fertilizer intelligent control system based on the method according to any one of claims 1 to 7, characterized in that: It includes: Several water and fertilizer mother liquor storage containers respectively communicated with the mixing pipe through the infusion pipeline. An electromagnetic valve for controlling the pipeline switch is provided on the infusion pipeline. The mixing pipe is also connected to an acid barrel for storing the PH adjustment liquid. An electromagnetic valve connecting the acid barrel for controlling the switch of the acid barrel is provided on the acid barrel. The liquid outlet of the mixing pipe is connected to the fertilizer pump, and a frequency converter for controlling the fertilizer suction rate of the fertilizer pump is also provided on the fertilizer pump; It also includes an EC sensor and a PH sensor for detecting the EC value and PH value of the water and fertilizer at the liquid outlet of the mixing pipe, and an EC sensor, a PH sensor, and an RH sensor for detecting the EC value, PH value, and soil moisture of the blueberry rhizosphere; Each solenoid valve, acid barrel connection solenoid, fertilizer pump, frequency converter and sensor are connected to the control module; The control module is used to control the switching state of the solenoid valve on the corresponding infusion pipeline during the fertilizer mixing cycle according to the ratio of each water-fertilizer mother solution, and is also used to control the inverter speed according to the water-fertilizer EC target value and the water-fertilizer EC measured value at the mixing pipe outlet. It is also used to control the switching state of the solenoid valve connected to the acid barrel according to the water-fertilizer PH target value and the water-fertilizer PH measured value at the mixing pipe outlet, and is also used to adjust the water-fertilizer EC target value, PH target value, and the irrigation duration of each time of the timed rotation irrigation according to the EC measured value, PH measured value, and soil moisture measured value of the blueberry root system.

9. The water and fertilizer intelligent control system according to claim 8, characterized in that: The control module is also provided with an input setting module for initializing the water-fertilizer EC target value, the PH target value, the irrigation duration of each time-controlled rotation irrigation, the ratio of the water-fertilizer mother solution and related parameter values.

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