阅读说明：本技术 土壤墒情检测装置及检测方法 (Soil moisture content detection device and detection method ) 是由 丁卫东 于 2021-09-23 设计创作，主要内容包括：本发明提供一种土壤墒情检测装置及检测方法,属于土壤墒情检测技术领域,包括电源模块、测量电极、标准电容、基准电极以及采集模块；电源模块通过充电按钮串联连接有继电器,所述继电器的两个输出端分别连接所述测量电极和所述基准电极；所述标准电容连接在所述基准电极和所述测量电极之间,所述采集模块的两端分别连接所述测量电极和所述基准电极。本发明电极放电电阻参数含有丰富的信息,为土壤特征提供了准确的信息；在测量电极位置保持不变的情形下,电极的放电电阻可表征所在土壤的墒情,实现了土壤墒情的准确定量；测量电极直接打入土壤,简单、可靠,测量的是电极周围土壤的整体特性,所反映的土壤湿度更准确、更有代表。(The invention provides a soil moisture content detection device and a detection method, which belong to the technical field of soil moisture content detection and comprise a power module, a measuring electrode, a standard capacitor, a reference electrode and an acquisition module; the power supply module is connected with a relay in series through a charging button, and two output ends of the relay are respectively connected with the measuring electrode and the reference electrode; the standard capacitor is connected between the reference electrode and the measuring electrode, and two ends of the acquisition module are respectively connected with the measuring electrode and the reference electrode. The electrode discharge resistance parameters of the invention contain rich information, and provide accurate information for soil characteristics; under the condition that the position of the measuring electrode is kept unchanged, the discharge resistance of the electrode can represent the soil moisture content of the soil, so that the soil moisture content can be accurately quantified; the measuring electrode is directly driven into soil, the method is simple and reliable, the overall characteristics of the soil around the electrode are measured, and the reflected soil humidity is more accurate and representative.)

1. The utility model provides a soil moisture content detection device which characterized in that includes:

the device comprises a power supply module, a measuring electrode, a standard capacitor, a reference electrode and an acquisition module;

the power supply module is connected with a relay in series through a charging button, and two output ends of the relay are respectively connected with the measuring electrode and the reference electrode; the standard capacitor is connected between the reference electrode and the measuring electrode, and two ends of the acquisition module are respectively connected with the measuring electrode and the reference electrode;

wherein the content of the first and second substances,

the power supply module is used for charging the measuring electrode and the standard capacitor; the acquisition module is used for acquiring the standard capacitance and the discharge time of the measuring electrode.

2. The soil moisture content detection device of claim 1, wherein the standard electrode and the measurement electrode each comprise a resistance to ground and a capacitance to ground in parallel.

3. The soil moisture content detection device according to claim 1, wherein a first normally open contact is arranged between one output end of the relay and the measuring electrode, and a second normally open contact is arranged between the other output end of the relay and the reference electrode.

4. The soil moisture content detection device of claim 1, wherein the power module comprises a battery.

5. The soil moisture content detection device of claim 4, wherein the power module further comprises a photovoltaic panel for charging the battery.

6. The soil moisture content detection device of claim 1, wherein the standard capacitor is a terylene capacitor.

7. The soil moisture content detection device of claim 1, wherein the collection module is a wave recorder or an oscilloscope.

8. The soil moisture content detection device of claim 1, wherein the collection module is communicatively connected to a background computer system via a communication module.

9. The soil moisture content detection device of claim 8, wherein the communication module is an RS485 communication network.

10. A soil moisture content detecting method using the soil moisture content detecting device according to any one of claims 1 to 9, comprising:

setting a grounding point as a zero-potential reference point of the ground;

charging and discharging a standard capacitor and a measuring electrode through a power supply module, recording and measuring the discharging time by using an acquisition module, and calculating the discharging resistance of the measuring electrode by combining the capacitance of the standard capacitor;

wherein the content of the first and second substances,

inserting a metal rod as a reference electrode into the zero potential reference point, and inserting a measuring electrode into the ground at a certain distance from the reference electrode;

the discharge resistance is the ratio of the discharge time to the capacitance of the standard capacitor.

Technical Field

The invention relates to the technical field of soil moisture content detection, in particular to a soil moisture content detection device and a detection method.

Background

In the agricultural field, the soil moisture content generally represents the drought degree of soil and is a key index for crop growth. At present, a humidity sensor measuring method is generally adopted for measuring the drought degree of soil, namely, a humidity sensor is buried in the soil to measure the relative humidity content of the soil, in the method, the sensor only reflects the humidity of a medium attached to the surface of the sensor, and reflects a point-shaped humidity which cannot represent the humidity parameter of a soil medium with a large area, the measured humidity result has large limitation, the measured result cannot reflect the humidity of the soil more comprehensively and accurately, the humidity sensor is easy to corrode after being used in the soil for a long time, the service life is seriously influenced, in addition, only the water content of the soil is measured, and the soil moisture information of the soil cannot be reflected accurately and comprehensively.

Disclosure of Invention

The invention aims to provide a soil moisture content detection device and a detection method for directly representing soil moisture content by using the resistance value of a discharge resistor of an electrode by adopting a method for measuring the discharge resistor of the electrode, so as to solve at least one technical problem in the background technology.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect, the present invention provides a soil moisture content detection device, comprising:

the device comprises a power supply module, a measuring electrode, a standard capacitor, a reference electrode and an acquisition module;

the power supply module is connected with a relay in series through a charging button, and two output ends of the relay are respectively connected with the measuring electrode and the reference electrode; the standard capacitor is connected between the reference electrode and the measuring electrode, and two ends of the acquisition module are respectively connected with the measuring electrode and the reference electrode;

wherein the content of the first and second substances,

the power supply module is used for charging the measuring electrode and the standard capacitor; the acquisition module is used for acquiring the standard capacitance and the discharge time of the measuring electrode.

Preferably, the standard electrode and the measuring electrode both comprise a resistance to ground and a capacitance to ground in parallel.

Preferably, a first normally open contact is arranged between one output end of the relay and the measuring electrode, and a second normally open contact is arranged between the other output end of the relay and the reference electrode.

Preferably, the power module includes a battery.

Preferably, the power module further comprises a photovoltaic panel, and the photovoltaic panel is used for charging the storage battery.

Preferably, the standard capacitor is a terylene capacitor.

Preferably, the acquisition module is a wave recorder or an oscilloscope.

Preferably, the acquisition module is in communication connection with a background computer system through a communication module.

Preferably, the communication module is an RS485 communication network.

In a second aspect, the present invention provides a soil moisture content detection method using the soil moisture content detection apparatus, comprising:

setting a grounding point as a zero-potential reference point of the ground;

charging and discharging a standard capacitor and a measuring electrode through a power supply module, recording and measuring the discharging time by using an acquisition module, and calculating the discharging resistance of the measuring electrode by combining the capacitance of the standard capacitor;

wherein the content of the first and second substances,

inserting a metal rod as a reference electrode into the zero potential reference point, and inserting a measuring electrode into the ground at a certain distance from the reference electrode;

the discharge resistance is the ratio of the discharge time to the capacitance of the standard capacitor.

The invention has the beneficial effects that: the electrode discharge resistance parameters contain rich information, and accurate information is provided for soil characteristics; under the condition that the position of the measuring electrode is kept unchanged, the discharge resistance of the electrode is only related to the water content of the soil generally, the soil moisture content of the soil can be represented, and the measuring accuracy of the soil moisture content is realized; the measuring electrode is directly driven into soil, the method is simple and reliable, the overall characteristics of the soil around the electrode are measured, and the reflected soil humidity is more accurate and representative.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic diagram of a soil moisture content detecting apparatus according to embodiment 1 of the present invention;

FIG. 2 is a structural diagram of a soil moisture content detecting apparatus according to embodiment 2 of the present invention;

fig. 3 is a schematic view illustrating a state of use of the soil moisture content detection apparatus according to embodiment 3 of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below by way of the drawings are illustrative only and are not to be construed as limiting the invention.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

In the description of the present specification, the terms "first", "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present specification, the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, only for convenience of description and simplification of description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present technology.

Unless expressly stated or limited otherwise, the terms "mounted," "connected," "coupled," and "disposed" are intended to be inclusive and mean, for example, that they may be fixedly coupled or disposed, or that they may be removably coupled or disposed, or that they may be integrally coupled or disposed. The specific meaning of the above terms in the present technology can be understood by those of ordinary skill in the art as appropriate.

For the purpose of facilitating an understanding of the present invention, the present invention will be further explained by way of specific embodiments with reference to the accompanying drawings, which are not intended to limit the present invention.

It should be understood by those skilled in the art that the drawings are merely schematic representations of embodiments and that the elements shown in the drawings are not necessarily required to practice the invention.

Example 1

Any conductor that has a positive charge, so long as there is a conductive path, will leak to the negative charge side. The earth is an infinite conductor and any earth current flows to earth. The discharge rate of the electric charge of the electrode inserted into the soil is closely related to the soil medium, the water content and the like, under the condition of a certain medium, the discharge rate of the electric charge on the electrode is only directly related to the water content of the soil, and the discharge rate is directly dependent on the discharge resistance of the electrode, so the discharge resistance of the electrode can represent the soil moisture content condition. Based on this, embodiment 1 of the present invention provides a circuit structure for measuring a discharge resistor of an electrode discharging to the ground, and the measured resistance value of the discharge resistor is used to directly represent soil moisture.

As shown in fig. 1, the circuit structure for measuring discharge resistance provided in this embodiment 1. The circuit structure comprises a power supply module, a charging button PB and a charging and quick cutting circuit formed by connecting relays J in series, and further comprises normally open contacts J1 and J2 connected with two ends of the relay J, a J1 connecting contact U is used for connecting a measuring electrode, the measuring electrode consists of a measuring resistor R and a measuring capacitor C connected in parallel, and a J2 connecting contact U is used for connecting the measuring electrode₀Contact U₀For connecting a reference electrode consisting of a reference resistor R₀And a reference capacitor C connected in parallel₀And (4) forming. A standard capacitor C is connected between the J1 and the J2_stdAnd the standard capacitor is connected with an acquisition module in parallel, and the acquisition module is used for acquiring the discharge time of the standard capacitor and the measuring resistor R.

In this embodiment 1, the acquisition module uses a wave recorder, and the positive electrode of the wave recorder is connected to the measurement electrode and the negative electrode is connected to the reference electrode. The charging and quick cutting circuit can charge the standard capacitor and the measuring resistor R, the power supply can be cut off quickly after charging is finished, and the used power supply module is a direct-current power supply E, can be a storage battery and is used for charging the standard capacitor and the measuring resistor R.

In embodiment 1, the principle and process of measuring the discharge resistance using the circuit configuration shown in fig. 1 are as follows:

when the charge button PB is first pressed, the relay J is electrified, the power supply E is switched on through the two normally open contacts J1 and J2 thereof, and the measurement capacitor C and the standard capacitor C of the measurement electrode are supplied_stdAnd (6) charging. After a few seconds, the charge button PB is released, the relay J loses power, the two normally open contacts are simultaneously disconnected, and the power supply E is quickly cut off from the circuit. At this time, the standard capacitance C_stdAnd the charge on the capacitance to ground of the measurement electrode (i.e., measurement capacitance C) will be discharged to ground through the discharge resistance (i.e., measurement resistance R) due to the capacitance to ground of the reference electrode (i.e., reference capacitance C)₀) Very small and C₀The charge on the capacitor passes through the discharge resistor (i.e., reference resistor R)₀) The release is fast and therefore the influence of the reference electrode is negligible and the negative terminal of the recorder can be considered as the ideal ground.

The discharge curve measured by the oscillograph is actually the standard capacitance C_stdAnd measuring the discharge time of the total capacitance after the capacitance C is connected in parallel if the standard capacitance C_stdThe capacitance is more than 10 times of the capacitance of the measuring electrode to the ground (namely the measuring capacitance C), the influence of the measuring electrode to the ground capacitance can be ignored, therefore, the discharge time recorded and measured by the oscillograph is the standard capacitance C_stdAnd measuring the discharge time of the electrode discharge resistor, and calculating to obtain an approximate discharge resistor according to the discharge time equal to the product of the discharge resistor and the capacitance of the standard capacitor. The larger the capacitance of the reference capacitor, the more accurate the value of the discharge resistance is calculated.

Example 2

This embodiment 2 provides a soil moisture content detection device. This soil moisture content detection device comes the representation soil moisture content through the resistance of measuring discharge resistor.

As shown in fig. 2, the circuit structure of the soil moisture content detecting device according to this embodiment 2 includes:

one end of the power module and relays J3 and J4 which are connected in series is connected with the anode of the power module, the other end of the J3 is connected with a contact G1, and the contact G1 is used for connecting a measuring electrode; one end of the J4 is connected with the anode of the power supply module, the other end is connected with a standard capacitor C3, one end of the standard capacitor C3 is connected with a contact G0, and the contact G0 is used for connecting a reference electrode. The C3 and the J4 are also connected with two resistors R5 and R6 which are connected in series in parallel, the resistance values of the resistors R5 and R6 are different, two pins of the microprocessor MCU of the acquisition module are respectively connected with the resistors R7 and R8, and the resistance values of the resistors R7 and R8 are the same. The other two pins of the microprocessor MCU are respectively connected with the relay J3 and the relay J4, the microprocessor MCU is also connected with a nixie tube display driver and a keyboard control chip CH452, and the microprocessor MCU is also connected with a communication module so as to transmit data to a background computer system through the communication module. The communication module uses an RS485 communication network.

The contact G1 is used to connect a measuring electrode comprising a measuring resistor R1 and a measuring capacitor C1 in parallel therewith. In this embodiment 2, the acquisition module uses a wave recorder, and may also use an oscilloscope. The microprocessor MCU automatically switches on the relays J3 and J4, an internal 48V power supply (namely a power supply module) charges a measuring capacitor C1 connected with a measuring resistor R1 in parallel, then switches off the J3, the charges on the standard capacitor C3 are discharged through R1, and simultaneously the MCU automatically records and measures high potential voltage and low potential voltage, so that the discharge time of the capacitor C3 is measured, therefore, the discharge resistor of the measuring resistor R1 can be calculated, and the value of the discharge resistor represents the conductivity degree of soil.

In this embodiment 2, the resistor R5 is used with a resistance of 100k, the resistor R6 is used with a resistance of 6.8k, and the resistors R7 and R8 are used with a resistance of 1 k.

In specific use, the resistances of the resistors R5, R6, R7 and R8 can be selected according to specific conditions, so as to ensure that the resistances of R5 and R6 are one large and one small, and the resistances of R7 and R8 are the same.

In this embodiment 2, the standard capacitor C3 is a dacron capacitor. The Polyester Capacitor (Polyester Capacitor) is formed by taking two metal foils as electrodes, clamping the electrodes in an extremely thin insulating medium and rolling the electrodes into a cylindrical or flat cylindrical core, wherein the medium is Polyester, and the Polyester film Capacitor is high in dielectric constant, small in size, large in capacity, good in stability and suitable for being used as a bypass Capacitor.

Example 3

As shown in fig. 3, this embodiment 3 provides a soil moisture content detecting device (GMU), which comprises a case, the circuit structure of embodiment 2 is disposed in the case, and two connecting contacts G3 and G4 are disposed on the case, wherein, in use, G3 is connected to a measuring electrode, the measuring electrode comprises a measuring resistor R3 and a measuring capacitor C4 connected in parallel with R3, G4 is connected to a reference electrode, and the reference electrode comprises a reference resistor R4 and a reference capacitor C5 connected in parallel with R4. The box body is also provided with a CH452 interface and an RS485 interface which are connected with the display module. The display module may be an LED display.

In this embodiment 3, the power module is a storage battery placed in the box body. In specific use, the solar photovoltaic panel can be used as a charging power supply to charge the storage battery.

In this embodiment 3, when using foretell soil moisture content detection device to carry out soil moisture content and detecting:

setting a grounding point as a zero-potential reference point of the ground, connecting a contact G4 of the GMU with a reference electrode, wherein the reference resistance of the reference electrode can be a metal rod, and inserting the metal rod into the zero-potential reference point; another resistor is then connected to contact G3 of the GMU as a measurement resistor, inserted in earth at a distance from the reference resistor, which resistor is connected in parallel with a capacitor C4. And turning on a GMU power switch, charging and discharging the standard capacitor and the measuring electrode through the power module, recording and measuring the discharge time by using the acquisition module, calculating the discharge resistance of the measuring electrode by combining the capacitance of the standard capacitor, and displaying the discharge resistance of the measuring electrode through the LED display.

In summary, in the soil moisture content detection apparatus and detection method according to the embodiments of the present invention, the physical characteristic of the soil electrode discharge resistance is the conductive characteristic of the soil, and the conductive characteristic is related to various factors of the soil, and is closely related to not only the water content of the soil, but also the ph value of the soil, metal ions, chemical ions, and medium components, so that the information represented by the electrode discharge resistance parameter is very rich, and can reflect the comprehensive characteristics of the soil.

The proposed discharge resistance characteristics provide accurate information for recognizing the soil characteristics of the earth surface and have important scientific value. Under the condition that the position of the measuring electrode is kept unchanged, the discharge resistance of the electrode is only related to the water content of soil generally, so that the soil moisture content of the soil can be represented, the soil moisture content can be accurately quantified, and an accurate quantification standard is provided for current and future digital agriculture. The measuring electrode is directly driven into soil, and is simple and reliable, the overall characteristics of the soil around the electrode are measured, and the soil humidity is not reflected by only one point like a humidity sensor, so that the reflected soil humidity is more accurate and representative. Can completely replace the prior soil humidity measuring device and has great economic and social benefits.

The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure, and various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Although the present disclosure has been described with reference to the specific embodiments shown in the drawings, it is not intended to limit the scope of the present disclosure, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive faculty based on the technical solutions disclosed in the present disclosure.