CN211235850U

CN211235850U - Soil moisture collection system

Info

Publication number: CN211235850U
Application number: CN201922086095.4U
Authority: CN
Inventors: 雷钢; 陈俊民; 孙建延; 李国选; 李银霞; 张作伟; 张耀祖; 黎中帅
Original assignee: Zhengzhou Institute of Technology
Current assignee: Zhengzhou Institute of Technology
Priority date: 2019-11-28
Filing date: 2019-11-28
Publication date: 2020-08-11
Anticipated expiration: 2029-11-28

Abstract

The utility model relates to a soil moisture collection system, the 0-5V soil moisture information that timing sampling module detected the probe is exported after the sample hold circuit keeps, wherein the cycle of sampling is switched on according to vegetation cycle trigger thyristor VTL2-VTL4 in the data processing module by singlechip, change timing circuit's time length control regularly, in order to realize controllable cycle sampling, later get into low pressure difference steady voltage module, AR2 comparison is put in fortune, during the low pressure difference, bidirectional diode D1 and thyristor VTL1 trigger the conduction, adjust the conduction degree of adjusting tube Q1, with stable output voltage, during unusual high pressure difference, bidirectional diode D2 switches on, put AR1 zero setting through the integrator to fortune, avoid the power unstability, the output signal that components and parts temperature drift caused is unusual, voltage directly exports or suppresses diode TVS1 through transient state through triode Q1 that falls the output module of switching on after the steady voltage and put in the noise, the output module directly exports or through the transient state, The diode D3, the inductor L2 and the electrolytic capacitor E4 are subjected to noise reduction and filtering and then output to the single chip microcomputer, and other noises and pulse interferences of a machine and the like are effectively inhibited.

Description

Soil moisture collection system

Technical Field

The utility model relates to an agricultural science technical field, especially a soil moisture collection system.

Background

Soil moisture is one of the important factors influencing crop growth, and is closely related to the growth condition of crops, in the fine agriculture production, the moisture content information in soil needs to be monitored for a long time and timely obtained, so as to realize accurate irrigation, thereby achieving the purpose of meeting the physiological water demand requirement of crops and not causing the waste of water resources, at present, soil moisture collection is carried out through a probe with the model of FDS-100, the probe is transmitted to a controller through a network communication interface, the controller controls a water pump to carry out irrigation with different amounts according to the physiological water demand requirement of the crops at different growth stages and the detected moisture in the soil, and the precision of the accurate irrigation depends on the precision of soil moisture detection.

The FDS-100 type probe consists of a probe, a power supply module, a transmission module, a zero-drift and temperature compensation module and a data processing module, wherein the data processing module can send data to a controller according to controllable periods of different growth stages of crops, but the probe samples according to a set sampling period (100 MHz) when acquiring the data, so that the frequency is high, the service life is influenced, and when the power supply module is unstable or other machines interfere with the power supply module, output signals are unstable, and signal abnormality influences the precision of signal measurement.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art exists, the utility model aims at providing a soil moisture collection system, the effectual probe of having solved can not controllable periodic sampling and output signal unstability, the unusual problem of signal.

The technical scheme includes that the device comprises a probe and a data processing module, and is characterized by further comprising a timing sampling module, a low-dropout voltage regulator module and a noise reduction output module, wherein the timing sampling module outputs 0-5V soil moisture information detected by the probe after the information is kept by a sampling and holding circuit composed of an MOS tube T1, a capacitor C1, a resistor R3 and an operational amplifier AR1, wherein a sampling period is controlled by a single chip in the data processing module according to a plant growth period triggering thyristor VTL2-VTL4 to be conducted, the timing duration of a timing circuit with a chip U1 as a core is changed, then the timing duration enters the low-dropout voltage regulator module, the operational amplifier AR2 is compared, the bidirectional diode D1 and the thyristor VTL1 are triggered to be conducted during low dropout, the conduction degree of a regulating tube Q1 is regulated to stabilize output voltage, the bidirectional diode AR2 is conducted during abnormal high dropout, and the operational amplifier AR3 is used as a core to zero regulation on an operational amplifier 1, the voltage after voltage stabilization is directly output through a transistor Q1 conducted in the noise reduction output module or output to a singlechip after noise reduction and filtering through a transient suppression diode TVS1, a diode D3, an inductor L2 and an electrolytic capacitor E4, wherein the transistor Q1 is conducted at low voltage difference.

The utility model has the advantages that: firstly, 0-5V soil moisture information detected by a probe is output after being held by a sample and hold circuit, wherein the sampling period is switched on by a single chip microcomputer in a data processing module according to a plant growth period trigger thyristor VTL2-VTL4, the timing duration control of a timing circuit taking a chip U1 as a core is changed, and the sampling in the controllable sampling period of the probe is realized;

secondly, by comparing the operational amplifier AR2, when the voltage difference is low, the bidirectional diode D1 and the thyristor VTL1 are triggered to conduct, the conduction degree of the adjusting tube Q1 is adjusted to stabilize the output voltage, then the voltage is directly output by the conducted triode Q1, when the voltage difference is abnormally high, the bidirectional diode D2 is conducted, the operational amplifier AR1 is zeroed by the integrator taking the operational amplifier AR3 as the core, the output signal abnormality caused by unstable power supply and temperature drift of components is avoided, noise reduction and filtering are carried out by the transient suppression diode TVS1, the diode D3, the inductor L2 and the electrolytic capacitor E4, the noise and the pulse interference are output to a single chip microcomputer, other noises and pulse interference of machines and the like are effectively suppressed, and the accuracy of signal measurement is improved.

Drawings

Fig. 1 is a schematic diagram of the circuit connection of the present invention.

Detailed Description

The foregoing and other technical and scientific aspects, features and advantages of the present invention will be apparent from the following detailed description of the embodiments, which is to be read in connection with the accompanying fig. 1. The structural contents mentioned in the following embodiments are all referred to the attached drawings of the specification.

Exemplary embodiments of the present invention will be described below with reference to the accompanying drawings.

A soil moisture collection system comprises a probe, a data processing module, a timing sampling module, a low-pressure-difference voltage stabilization module and a noise reduction output module, wherein the timing sampling module outputs 0-5V soil moisture information detected by the probe after being held by a sampling and holding circuit consisting of an MOS tube T1, a capacitor C1, a resistor R3 and an operational amplifier AR1, wherein the sampling period is output after being triggered by a singlechip in the data processing module according to the plant growth period to trigger a thyristor VTL2-VTL4 to be conducted, the timing duration control of a timing circuit taking a chip U1 as a core is changed, the sampling in the controllable sampling period of the probe is realized, then the sampling enters the low-pressure-difference voltage stabilization module, the operational amplifier AR2 is used for comparison, the bidirectional diode D1 and the thyristor VTL1 are triggered and conducted in the low-pressure difference, the conduction degree of a regulating tube Q1 is adjusted to stabilize the output voltage, and then the voltage is directly output to the singlechip Q1 conducted, when the voltage is abnormally high, the bidirectional diode D2 is conducted, the operational amplifier AR1 is zeroed through an integrator taking the operational amplifier AR3 as a core, the voltage after voltage stabilization is subjected to noise suppression and transient pulse interference through a transient suppression diode TVS1 in the noise reduction output module, the diode D3 is further conducted in a unidirectional mode, negative signals are filtered, and the inductor L2 and the electrolytic capacitor E4 are filtered and then output to the single chip microcomputer;

the timing sampling module limits the 0-5V soil moisture information detected by the probe through a diode D1 and a diode D2 which are connected in series, the information enters a sampling holding circuit consisting of an MOS tube T1, a capacitor C1, a resistor R3 and an operational amplifier AR1, when the sampling frequency is high, signals have enough time to be transmitted to a post-stage circuit, the holding time is the capacitance value of the capacitor C1, wherein the sampling period is determined by a clock instruction sent by a singlechip in the data processing module according to a plant growth period (specifically, the sampling period can be determined by a clock chip DS1302 and the three growth stages of crops, namely a growth period, the singlechip triggers the thyristors VTL2, VTL3 and VTL4 to be conducted, the resistors R15, R16 and R17 are connected with the resistor R5 in parallel in sequence, changing the resistance value after parallel connection, further changing the time constant (the value of the resistor R4, the value of the resistor R15, the value of the resistor R16, the value of the resistor R17 after being sequentially connected in parallel with the resistor R5, and the value of the capacitor C0), further changing the timing duration of a timing circuit composed of the NE555 chip U1, the resistor R4, the resistor R5, the capacitor C0, the capacitor C2, and the resistor R6, when the timing is reached, the NE555 chip U1 outputs high level to drive the MOS tube T1 to be conducted, and allowing sampling, wherein the timing circuit comprises the probe X1, the pin 1 of the probe X1 is connected with +12V, the pin 3 of the probe X1 is connected with the ground, the pin 2 of the probe X1 is connected with one end of the resistor R1, the other end of the resistor R1 is respectively connected with the anode of the diode D1, the cathode of the diode D365V, the source of the resistor R1 is connected with the drain of the MOS tube T1, and the source of the MOS tube T1 is respectively connected with the drain, One end of a resistor R3, the other end of a resistor R3 is connected to a non-inverting input terminal of an operational amplifier AR1, an inverting input terminal of the operational amplifier AR1 is connected to the left end of a potentiometer RW2, an output terminal of the operational amplifier AR1 is connected to the right end of a potentiometer RW2, a gate of the MOS transistor T1 is connected to pin 3 of a chip U1, pin 4 and pin 8 of the chip U1 are connected to +5V, pin 7 of the chip U1 is connected to one end of a resistor R4, one end of a resistor R5, an anode of a thyristor VTL2, an anode of a thyristor VTL3, an anode of a VTL4, a cathode of the thyristor VTL4, one end of the resistor R4, the other end of the resistor R4 is connected to +5V, the other end of the resistor R4 is connected to pin 2 and pin 6 of the chip U4, one end of a capacitor C4, and the other end of the resistor R4, the other end of the resistor R36, The other end of the resistor R17, the other end of the capacitor C0 and the pin 1 of the chip U1 are connected to the ground, the pin 5 of the chip U1 is respectively connected with one end of the grounded capacitor C2 and one end of the grounded resistor R6, and the control electrode of the thyristor VTL2, the control electrode of the thyristor VTL3 and the control electrode of the thyristor VTL4 are respectively triggered and controlled by the single chip microcomputer according to the high level output by the three periods of the plant growth cycle.

The low-voltage-difference voltage stabilizing module receives a voltage after sampling and holding, is adjusted by an adjusting tube Q1 and then is filtered by an inductor L1 and then is output, specifically, an inverting input end of an operational amplifier AR2 is connected to an adjusting tube Q1 through a resistor R7 to adjust a front voltage, an inverting input end of an operational amplifier AR2 divides the voltage by a resistor R11 and a resistor R12 and then adjusts a rear voltage of an adjusting tube Q1, the operational amplifier AR2 compares the rear voltage and charges a capacitor C4 through a resistor R9, when the compared rear voltage is low-voltage difference, a bidirectional diode D1 is conducted, a thyristor VTL1 is triggered and conducted, the low-voltage difference (0-5V) is added to a base electrode of the adjusting tube Q1, the conduction degree of the adjusting tube Q1 is adjusted to stabilize an output voltage, when the abnormal high-voltage difference is generated (higher than 5V and lower than-5V), the bidirectional diode D2 is conducted, and when the abnormal high-voltage difference is generated, the abnormal high-voltage difference is generated by zero adjustment of the operational amplifier AR, the circuit comprises a triode Q1 and a resistor R8, wherein one end of a collector of a triode Q1 and one end of a resistor R8 are both connected with an output end of an operational amplifier AR1, an emitter of the triode Q1 is connected with one end of an inductor L1, the other end of the inductor L1 is connected with one end of a resistor R11, the other end of a resistor R11 is respectively connected with one end of a grounding resistor R12, one end of a bidirectional thyristor D2 and a non-inverting input end of the operational amplifier AR2, an inverting input end of the operational amplifier AR2 is connected with an output end of the operational amplifier AR1 through a resistor R7, an output end of the operational amplifier AR1 is respectively connected with one end of a resistor R1 and a cathode of a thyristor VTL1, the other end of the resistor R1 is respectively connected with one end of a grounding capacitor C1, one end of a bidirectional diode D1 and a control electrode of the bidirectional thyristor D1, the other end of the bidirectional thyristor D1 is connected with a control electrode of the, the other end of the bidirectional thyristor D2 is connected with one end of a resistor R10, the other end of the resistor R10 is respectively connected with the inverting input end of an operational amplifier AR3 and one end of a capacitor C3, the non-inverting input end of the operational amplifier AR3 is connected with the ground, and the output end of the operational amplifier AR3 and the other end of the capacitor C3 are connected with the adjustable end of a potentiometer RW 2;

the noise reduction output module receives regulated voltage, when the voltage difference is low, the triode Q1 is conducted, the conducted triode Q1 directly outputs the regulated voltage, when the voltage difference is abnormally high, the regulated voltage is subjected to noise suppression and transient pulse interference through the transient suppression diode TVS1, the diode D3 is further conducted in a single direction, negative signals are filtered, the inductor L2 and the electrolytic capacitor E4 are filtered and then output to the single chip microcomputer, the noise reduction output module comprises a diode D3, a transient suppression diode TVS1 and a triode Q2, the anode of the diode D3, one end of the transient suppression diode TVS1, the emitter of the triode Q2 is connected with the other end of the inductor L1, the cathode of the diode D3 is connected with one end of the inductor L2, the other end of the inductor L2, the anode of the electrolytic capacitor E4 and the collector of the triode Q2 are connected with the single chip microcomputer, the other end of the transient suppression diode TVS1 and the cathode of the electrolytic capacitor E4 are connected with the ground, one end of the resistor R14, the other end of the resistor R14 is connected with a power supply of-5V, and the other end of the resistor R13 is connected with the base electrode of the triode Q1.

When the utility model is used, 0-5V soil moisture information detected by the probe enters a sampling holding circuit to be held after amplitude limiting, so that when the sampling frequency is high, signals have enough time to be transmitted to a rear-stage circuit, the holding time is the capacitance value of a capacitor C1, the sampling period is that a single chip microcomputer in a data processing module triggers a thyristor VTL2, a VTL3 and a VTL4 to be conducted according to the plant growth period, a resistor R15, a resistor R16 and a resistor R17 are connected in parallel with a resistor R5 in sequence, the resistance value after parallel connection is changed, a time constant is changed, the timing duration of a timing circuit is changed, when the timing is reached, an NE555 chip U1 outputs high level, a driving MOS tube T1 is conducted, the sampling is allowed by control, the voltage is output after being adjusted by an adjusting tube Q1 and filtered by an inductor L1, specifically, the AR2 is connected into an adjusting tube Q1 to adjust the front and back voltage, AR2 charges a capacitor C38 through a resistor R3985 after comparison, when the compared voltage is low voltage difference, the bidirectional diode D1 is conducted, the thyristor VTL1 is triggered and conducted, the low voltage difference (0-5V) is added to the base electrode of the adjusting tube Q1 to adjust the conducting degree of the adjusting tube Q1, the output voltage is stabilized and then directly output to the singlechip through the triode Q1 conducted in the noise reduction output module, when the voltage difference is abnormally high, the bidirectional diode D2 is conducted, the operational amplifier AR1 is zeroed by an integrator taking the operational amplifier AR3 as a core, the output signal abnormality caused by unstable power supply and temperature drift of components is avoided, voltage after voltage stabilization is subjected to noise suppression and transient pulse interference through a transient suppression diode TVS1 in a noise reduction output module, a diode D3 is further subjected to one-way conduction, negative signals are filtered, the inductor L2 and an electrolytic capacitor E4 are filtered and then output to a single chip microcomputer, other noises and pulse interference of machines and the like are effectively suppressed, and the accuracy of signal measurement is improved.

Claims

1. A soil moisture acquisition system comprises a probe and a data processing module, and is characterized by further comprising a timing sampling module, a low-pressure-difference voltage stabilizing module and a noise reduction output module, wherein 0-5V soil moisture information detected by the probe is output after being held by a sampling and holding circuit consisting of an MOS tube T1, a capacitor C1, a resistor R3 and an operational amplifier AR1, a sampling period is controlled by a single chip microcomputer in the data processing module according to a plant growth period to trigger a thyristor VTL2-VTL4 to be conducted, the timing duration of a timing circuit taking a chip U1 as a core is changed to be controlled, then the timing circuit enters the low-pressure-difference voltage stabilizing module, the operational amplifier AR2 is compared, a bidirectional diode D1 and the thyristor VTL1 are triggered to be conducted during low-pressure difference, the conduction degree of an adjusting tube Q1 is adjusted to stabilize output voltage, the bidirectional diode D2 is conducted during abnormal high-pressure difference, an integrator taking an operational amplifier AR3 as the core is used for carrying out zero adjustment on an operational, the voltage after voltage stabilization is directly output through a transistor Q1 conducted in the noise reduction output module or output to a singlechip after noise reduction and filtering through a transient suppression diode TVS1, a diode D3, an inductor L2 and an electrolytic capacitor E4, wherein the transistor Q1 is conducted at low voltage difference.

2. The soil moisture collection system of claim 1, wherein the timing sampling module comprises a probe X1, a pin 1 of the probe X1 is connected with +12V, a pin 3 of the probe X1 is connected with ground, a pin 2 of the probe X1 is connected with one end of a resistor R1, the other end of the resistor R1 is connected with an anode of a diode D1, a cathode of a diode D2 and one end of a resistor R2 respectively, an anode of a diode D2 is connected with ground, a cathode of the diode D1 is connected with +5V, the other end of a resistor R2 is connected with a source of a MOS tube T1, a drain of the MOS tube T1 is connected with one end of a capacitor C1 and one end of a resistor R3 respectively, the other end of the resistor R3 is connected with a non-inverting input end of an operational amplifier AR1, an inverting input end of the operational amplifier AR1 is connected with a left end of a potentiometer 2, an output end of the operational amplifier AR1 is connected with a right end of a potentiometer 2, a gate of the MOS tube T1, pin 4 and pin 8 of chip U1 are connected with a power supply +5V, pin 7 of chip U1 is connected with one end of a resistor R4, one end of a resistor R5, the anode of a thyristor VTL2, the anode of a thyristor VTL3, the anode of a thyristor VTL4, the cathode of a thyristor VTL2, the cathode of a thyristor VTL3, and the cathode of a thyristor VTL4 are connected with one end of a resistor R15, one end of a resistor R16, and one end of a resistor R17, the other end of a resistor R4 is connected with the power supply +5V, the other end of a resistor R5 is connected with pin 2 and pin 6 of chip U1, one end of a capacitor C0, the other end of a resistor R15, the other end of a resistor R16, and the other end of a resistor R17, the other end of a capacitor C0 and pin 1 of chip U1 are connected with ground, pin 5 of chip U1 is connected with one end of a ground capacitor C36, and the control electrode of the thyristor VTL2, the control electrode of the thyristor VTL3 and the control electrode of the thyristor VTL4 are respectively triggered and controlled by the singlechip according to the high level output by three periods of the plant growth cycle.

3. The soil moisture collecting system of claim 1, wherein the low dropout voltage regulator module comprises a transistor Q1 and a resistor R8, one end of a collector of the transistor Q1 and one end of a resistor R8 are both connected with an output end of an operational amplifier AR1, an emitter of the transistor Q1 is connected with one end of an inductor L1, the other end of the inductor L1 is connected with one end of a resistor R11, the other end of the resistor R11 is respectively connected with one end of a ground resistor R12, one end of a triac D2 and a non-inverting input end of the operational amplifier AR2, an inverting input end of the operational amplifier AR2 is connected with an output end of an operational amplifier AR1 through a resistor R7, an output end of the operational amplifier AR 9 is respectively connected with one end of a resistor R9 and a cathode of a thyristor L1, the other end of the resistor R9 is respectively connected with one end of a ground capacitor C4, one end of a triac D1 and a control electrode of a triac D2, and the other end of a control electrode of a, the anode of the thyristor VTL1 is connected with one end of a resistor R8 and the base of a triode Q1 respectively, the other end of the bidirectional thyristor D2 is connected with one end of a resistor R10, the other end of the resistor R10 is connected with the inverting input end of an operational amplifier AR3 and one end of a capacitor C3 respectively, the non-inverting input end of the operational amplifier AR3 is connected with the ground, and the output end of the operational amplifier AR3 and the other end of the capacitor C3 are connected with the adjustable end of a potentiometer RW 2.

4. The soil moisture collection system of claim 1, wherein the noise reduction output module comprises a diode D3, a transient suppression diode TVS1, a transistor Q2, a positive electrode of the diode D3, one end of the transient suppression diode TVS1, an emitter of the transistor Q2 connected to the other end of the inductor L1, a negative electrode of the diode D3 connected to one end of the inductor L2, the other end of the inductor L2, a positive electrode of the electrolytic capacitor E4, and a collector of the transistor Q2 connected to the single chip, the other end of the transient suppression diode TVS1 and a negative electrode of the electrolytic capacitor E4 connected to ground, a base of the transistor Q2 connected to one end of a resistor R13 and one end of a resistor R14, the other end of the resistor R14 connected to the power supply of-5V, and the other end of the resistor R13 connected to a base of the transistor Q1.