CN214037891U - Integrated double-layer composite pipeline leakage detection system - Google Patents
Integrated double-layer composite pipeline leakage detection system Download PDFInfo
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- CN214037891U CN214037891U CN202023266251.4U CN202023266251U CN214037891U CN 214037891 U CN214037891 U CN 214037891U CN 202023266251 U CN202023266251 U CN 202023266251U CN 214037891 U CN214037891 U CN 214037891U
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Abstract
The utility model discloses integrated double-deck compound pipeline system of leaking hunting, band-pass filter circuit receives the information of leaking hunting that the probe of pipeline leak detector detected, through band-pass filter frequency selection, export to the frequency-selective amplifier circuit after avoiding other frequency signal interference, at first restrain the noise signal of the less amplitude through the coring circuit, later further frequency-select and amplify the pipeline leak detector working frequency component signal through the frequency-selective amplifier circuit, finally enter the differential output circuit, carry out differential balance further amplification processing, restrain common mode interference, the information of leaking hunting that the probe of amplifying pipeline leak detector detected is transmitted to the host computer of pipeline leak detector, the measuring precision has been improved, the noise signal outside the pipeline leak detector working frequency component signal is amplified to the initiative noise reduction circuit adoption notch amplifier, the noise signal amplitude is high, and when the differential output circuit output signal is unusually high, the noise signal amplified by the trap amplifier is fed back to the differential output circuit to offset the noise amplitude component, so that the measurement precision is further improved.
Description
Technical Field
The utility model relates to an hourglass technical field especially relates to integrated double-deck compound pipeline system of leaking hunting.
Background
A pipeline is a device for transporting a gas, liquid or fluid with solid particles, connected by pipes, pipe couplings, valves, etc. The pipeline has wide application range, is mainly used in water supply, water drainage, heat supply, gas supply, long-distance petroleum and natural gas transmission, agricultural irrigation, hydraulic engineering and various industrial devices, and is an integrated double-layer composite pipeline which is formed by compounding two layers of pipes through some processing technologies and has a double-layer structure. At present, a pipeline leakage detector is mainly adopted, specifically, a probe detects leakage detection information, the leakage detection information is transmitted to a host, the signal is output to an earphone and a display after being processed, the integrated double-layer composite pipeline leakage detection is completed, but when the leakage is detected, especially the outdoor pipeline is measured, the influence of external noise interference is easily caused, and measurement errors are easily caused.
Disclosure of Invention
To the above situation, for overcoming prior art's defect, the utility model aims to provide an integrated double-deck compound pipeline system of leaking hunting, the effectual pipeline appearance of leaking hunting of having solved is easily influenced by external noise interference, causes measuring error's problem easily.
The technical scheme for solving the problem is that the active noise reduction circuit comprises a band-pass filter circuit, a frequency selection amplifying circuit, a differential output circuit and an active noise reduction circuit, and is characterized in that the band-pass filter circuit is connected with the frequency selection amplifying circuit, and the frequency selection amplifying circuit and the active noise reduction circuit are connected with the differential output circuit. The utility model discloses a mixing circuit subtracts electrical communication cabinet's PLC communication operating frequency signal and interference signal's frequency signal, output difference frequency signal, difference frequency signal is voltage signal for LM 331's frequency-to-voltage converter U1 conversion by the model, when voltage signal hour, photoelectric coupler OP1 input produces the electric current, photoelectric coupler OP1 switches on, and then triode Q2 switches on, the low level gets into operating mode switching circuit, trigger the PLC communication operating frequency who changes electrical communication cabinet, with the problem of avoiding same frequency interference to seriously influence communication quality.
Preferably, one end of the frequency-selective amplifying circuit capacitor C3, the capacitor C4, one end of the capacitor C3, and one end of the capacitor C4 are connected to the output signal of the band-pass filter circuit, the other end of the capacitor C3 are connected to one end of the resistor R5, one end of the ground resistor R7, and the anode of the diode D1, the other end of the capacitor C4 is connected to one end of the resistor R4, one end of the ground resistor R6, and the cathode of the diode D2, the anode of the diode D2 is connected to the cathode of the diode D1 and one end of the resistor R8, the other end of the resistor R8 is connected to one end of the resistor R9, one end of the ground resistor R10, and the base of the transistor Q1, the emitter of the transistor Q1 is connected to ground, the collector of the transistor Q1 is connected to one end of the primary coil of the transformer U1 and one end of the capacitor C1, the other end of the resistor R1, the other end of the primary coil of the resistor R1, and the other end of the resistor R1 are connected to the other end of the transformer U1, The other end of the capacitor C5 is connected with a power supply of +5V, and the secondary coil of the transformer U1 outputs signals for the frequency-selecting amplifying circuit.
The utility model discloses the information that leaks hunting that the probe of pipeline leak hunting appearance detected, band pass filter frequency selection at first, avoid other frequency signal interference promptly, later suppress the noise signal that the range is less through the coring circuit, frequency selection amplifier circuit further frequency selection and amplification to pipeline leak hunting appearance operating frequency component signal, carry out differential balance further amplification processing through the differential amplifier circuit that operational amplifier AR4, AR2, AR3 constitute finally, suppress common mode interference, the information that leaks hunting that the probe of amplifying pipeline leak hunting appearance detected, transmit to the host computer of pipeline leak hunting appearance, the precision of measurement has been improved, in addition still adopt notch amplifier to amplify the noise signal beyond pipeline leak hunting appearance operating frequency component signal, when noise signal range is high, stabilivolt Z1 punctures, and when differential output circuit output signal is unusually high, triode Q2 switches on, 5V triggers thyristor VTL1 to switch on, the noise signal amplified by the notch amplifier is fed back to the inverting input end of the operational amplifier AR4 through the punctured stabilivolt Z1 and the conducted thyristor VTL1 to offset the noise amplitude component, and the measurement precision is further improved.
Drawings
Fig. 1 is a schematic circuit diagram of the present invention.
Detailed Description
The foregoing and other technical matters, features and effects 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.
An integrated double-layer composite pipeline leakage detection system comprises a band-pass filter circuit, a frequency-selecting amplifier circuit, a differential output circuit and an active noise reduction circuit, wherein the band-pass filter circuit receives leakage detection information detected by a probe of a pipeline leakage detector, the frequency is selected by a band-pass filter, only a working frequency component signal of the pipeline leakage detector is allowed to pass, signals outside the frequency range are blocked, namely, the signals outside the frequency range are output to the frequency-selecting amplifier circuit after being prevented from being interfered by other frequency signals, firstly, the noise signals with smaller amplitude are inhibited by a coring circuit, then, the working frequency component signal of the pipeline leakage detector is further frequency-selected and amplified by the frequency-selecting amplifier circuit, the amplitude of useful signals is raised, the signals with other frequencies have stronger inhibition effect, finally, the signals enter the differential output circuit, and the differential balanced further amplification processing is carried out by adopting the input end of the differential amplifier circuit consisting of operational amplifiers AR4, AR2 and AR3, the method inhibits common mode interference and amplifies leakage detection information detected by a probe of the pipeline leakage detector, wherein an operational amplifier AR4 is a subtraction proportional amplifier, the output signals of operational amplifiers AR3 and AR2 are subjected to subtraction operation to output a difference signal, namely the leakage detection information detected by the probe of the pipeline leakage detector after common mode interference is eliminated is transmitted to the host of the pipeline leakage detector, the measurement precision is improved, the active noise reduction circuit adopts a trap amplifier to amplify noise signals except the working frequency component signals of the pipeline leakage detector, when the amplitude of the noise signals is high, a voltage regulator tube Z1 is punctured, and when the output signal of the differential output circuit is abnormally high, the triode Q2 is conducted, the +5V trigger thyristor VTL1 is conducted, the noise signal amplified by the trap amplifier is fed back to the inverting input end of the operational amplifier AR4 through the punctured voltage-stabilizing tube Z1 and the conducted thyristor VTL1 so as to offset the noise amplitude component, and the measurement precision is further improved.
On the basis of the scheme, the band-pass filter circuit receives leakage detection information detected by a probe of the pipeline leakage detector, frequency selection is carried out through a band-pass filter consisting of an operational amplifier AR1, resistors R1-R3, a capacitor C1 and a capacitor C2, only the working frequency component signals of the pipeline leakage detector are allowed to pass through, signals outside the frequency range are blocked, the output circuit is used for outputting signals after avoiding interference of other frequency signals and comprises a resistor R1, wherein the left end of the resistor R1 is connected with leakage detection information detected by a probe of a pipeline leakage detector, the right end of the resistor R1 is respectively connected with one end of a grounded capacitor C1, one end of a grounded resistor R2 and one end of a capacitor C2, the other end of the capacitor C2 is respectively connected with one end of a resistor R3 and the inverting input end of an operational amplifier AR1, the non-inverting input end of the operational amplifier AR1 is connected with the ground, and the other end of the capacitor C1, the other end of the resistor R3 and the output end of the operational amplifier AR1 are output signals of a band-pass filter circuit.
On the basis of the scheme, the frequency-selecting amplifying circuit receives an output signal of the band-pass filter circuit, firstly, a core-digging circuit consisting of capacitors C3 and C4, a resistor R4-a resistor R7, diodes D1 and D2 suppresses a noise signal with a smaller amplitude, then, a frequency-selecting amplifying circuit consisting of a triode Q1, a transformer U1, a resistor R8-a resistor R10 and a capacitor C5 further selects and amplifies working frequency component signals of the pipeline leakage detector to increase the amplitude of a useful signal, and has a stronger suppression effect on signals with other frequencies, the capacitors C3 and C4 are connected with one end of a capacitor C3 and one end of the capacitor C4 to output signals of the band-pass filter circuit, the other end of the capacitor C3 is respectively connected with one end of a resistor R5, one end of a ground resistor R7 and the positive electrode of a diode D1, and the other end of a capacitor C4 is respectively connected with one end of a resistor R4 and one end of a ground resistor R6, The negative electrode of the diode D2, the positive electrode of the diode D2 are respectively connected with the negative electrode of the diode D1 and one end of the resistor R8, the other end of the resistor R8 is respectively connected with one end of the resistor R9, one section of the grounding resistor R10 and the base electrode of the triode Q1, the emitter electrode of the triode Q1 is connected with the ground, the collector electrode of the triode Q1 is respectively connected with one end of the primary coil of the transformer U1 and one end of the capacitor C5, the other end of the resistor R4, the other end of the resistor R5, the other end of the resistor R9, the other end of the primary coil of the transformer U1 and the other end of the capacitor C5 are respectively connected with +5V of a power supply, and the secondary coil of the transformer U1 is used as an output signal of the frequency-selecting amplifying circuit.
On the basis of the scheme, the differential output circuit receives the output signal of the frequency-selecting amplifying circuit, the output signal is added to the input end of the differential amplifying circuit consisting of the operational amplifiers AR4, AR2 and AR3, the differential balance further amplification processing is carried out, the common-mode interference is inhibited, and the leakage detection information detected by the probe of the pipeline leakage detector is amplified, wherein the operational amplifier AR4 is a subtraction proportional amplifier, the output signals of the operational amplifiers AR3 and AR2 are subjected to subtraction operation to output a difference signal, namely the leakage detection information detected by the probe of the pipeline leakage detector after the common-mode interference is eliminated is transmitted to a host computer of the pipeline leakage detector, the measurement precision is improved, the differential output circuit comprises an operational amplifier AR2, an operational amplifier AR3 and a capacitor C6, the inverting input end of the operational amplifier AR3 and one end of the capacitor C6 are connected with one end of a secondary coil of a transformer U1, the non-inverting input end of the operational amplifier AR2 and the other end of the capacitor C6 are connected with the other end of a secondary coil of the transformer U1, the inverting input end of the operational amplifier AR2 is connected with the output end of the operational amplifier AR2 and one end of the resistor R11 respectively, the other end of the resistor R11 is connected with the non-inverting input end of the operational amplifier AR4 and one end of the resistor R13 respectively, the non-inverting input end of the operational amplifier AR3 is connected with the output end of the operational amplifier AR3 and one end of the resistor R12 respectively, the other end of the resistor R12 is connected with the inverting input end of the operational amplifier AR4 and one end of the grounding resistor R14 respectively, and the other end of the resistor R132 and the output end of the operational amplifier AR4 are connected with a host of the pipeline leakage detector.
On the basis of the scheme, the active noise reduction circuit amplifies noise signals (which can be measured by a noise measuring instrument) except for a pipeline leakage detector working frequency component signal by using a trap amplifier consisting of a capacitor C9-a capacitor C10, a resistor R16-a resistor R19 and an operational amplifier AR5, when the amplitude of the noise signals is high, a voltage regulator tube Z1 is broken down, and when the output signal of a differential output circuit is abnormally high, a triode Q2 is conducted, +5V trigger a thyristor VTL1 is conducted, the noise signals amplified by the trap amplifier are fed back to an inverting input end of the operational amplifier AR4 through the broken-down voltage regulator tube Z1 and the conducted thyristor VTL1 to offset the noise amplitude component, so that the measurement accuracy is further improved, and the active noise reduction circuit comprises a capacitor C7, the left end of the capacitor C7 is connected with the noise signals, and the right end of the capacitor C7 is respectively connected with the inverting input end of the operational amplifier AR5, one end of the resistor R16, One end of a resistor R17 and one end of a capacitor C9, the other end of a resistor R17 is respectively connected with one end of a resistor R18 and one end of a grounded capacitor C10, the other end of a capacitor C9 is respectively connected with one end of a grounded resistor R19 and one end of a capacitor C8, the non-inverting input end of an operational amplifier AR5 is connected with the ground, the output end of an operational amplifier AR5 is respectively connected with the other end of the resistor R16, the other end of the capacitor R18, the other end of the capacitor C8 and the negative electrode of a voltage regulator tube Z1, the positive electrode of the voltage regulator tube Z1 is connected with the positive electrode of a thyristor VTL1, the negative electrode of the thyristor VTL1 is connected with the inverting input end of the operational amplifier AR4, the control electrode of the thyristor VTL1 is connected with the emitter of a triode Q2, the collector of a triode Q2 is connected with a power supply of +5V, the base electrode of the triode Q2 is connected with the positive electrode of the voltage regulator tube Z2 through the resistor R5, and the negative electrode of the voltage regulator tube Z2 is connected with the output end of the operational amplifier Z4.
When the utility model is used in detail, the band-pass filter circuit receives the leakage detection information detected by the probe of the pipeline leakage detector, the frequency of the band-pass filter composed of the operational amplifier AR1, the resistor R1-R3, the capacitor C1 and the capacitor C2 is selected, only the working frequency component signal of the pipeline leakage detector is allowed to pass, the signal outside the frequency range is blocked, namely, the signal is output after avoiding the interference of other frequency signals, then the signal enters the frequency selection amplifying circuit, the core digging circuit composed of the capacitor C3 and the capacitor C4, the resistor R4-the resistor R7, the diode D1 and the D2 is used for restraining the noise signal with smaller amplitude, then the frequency selection amplifying is further carried out on the working frequency component signal of the pipeline leakage detector through the frequency selection amplifying circuit composed of the triode Q1, the transformer U1, the resistor R8-the resistor R10 and the capacitor C5, the amplitude of the useful signal is raised, and the signal with stronger restraining effect on other frequencies, finally, the output signal of the frequency-selecting amplifying circuit is received by a differential output circuit, and is added to the input end of a differential amplifying circuit consisting of operational amplifiers AR4, AR2 and AR3, and differential balance further amplification processing is carried out to inhibit common-mode interference and amplify leakage detection information detected by a probe of the pipeline leakage detector, wherein the operational amplifier AR4 is a subtraction proportional amplifier which carries out subtraction operation on the output signals of the operational amplifiers AR3 and AR2 to output a difference signal, namely the leakage detection information detected by the probe of the pipeline leakage detector after the common-mode interference is eliminated is transmitted to a host computer of the pipeline leakage detector, so that the measurement precision is improved, an active noise reduction circuit is arranged, a trap amplifier consisting of a capacitor C9-a capacitor C10, a resistor R16-a resistor R19 and an operational amplifier AR5 is adopted to amplify noise signals (which can be specifically given by noise measurement) except for the working frequency component signals of the pipeline leakage detector, when the amplitude of the noise signal is high, the voltage regulator tube Z1 is broken down, and when the output signal of the differential output circuit is abnormally high, the triode Q2 is conducted, the +5V trigger thyristor VTL1 is conducted, the noise signal after being amplified by the trap amplifier is fed back to the inverting input end of the operational amplifier AR4 through the broken-down voltage regulator tube Z1 and the conducted thyristor VTL1 so as to offset the noise amplitude component, and the measurement precision is further improved.
Claims (5)
1. The integrated double-layer composite pipeline leakage detection system comprises a band-pass filter circuit, a frequency selection amplifying circuit, a differential output circuit and an active noise reduction circuit, and is characterized in that the band-pass filter circuit is connected with the frequency selection amplifying circuit, and the frequency selection amplifying circuit and the active noise reduction circuit are connected with the differential output circuit.
2. The integrated double-layer composite pipeline leakage detection system according to claim 1, wherein the band-pass filter circuit comprises a resistor R1, the left end of the resistor R1 is connected with the leakage detection information detected by the probe of the pipeline leakage detector, the right end of the resistor R1 is respectively connected with one end of a grounding capacitor C1, one end of a grounding resistor R2 and one end of a capacitor C2, the other end of a capacitor C2 is respectively connected with one end of a resistor R3 and the inverting input end of an operational amplifier AR1, the non-inverting input end of the operational amplifier AR1 is connected with ground, and the other end of the capacitor C1, the other end of the resistor R3 and the output end of the operational amplifier AR1 are output signals of the band-pass filter circuit.
3. The integrated double-layer composite pipeline leakage detection system according to claim 1, wherein the frequency-selective amplifier circuit comprises a capacitor C3 and a capacitor C4, one end of a capacitor C3 and one end of a capacitor C4 are connected with an output signal of a band-pass filter circuit, the other end of the capacitor C3 is respectively connected with one end of a resistor R5, one end of a grounding resistor R7 and the anode of a diode D1, the other end of the capacitor C4 is respectively connected with one end of a resistor R4, one end of the grounding resistor R6 and the cathode of a diode D2, the anode of the diode D2 is respectively connected with the cathode of a diode D1 and one end of a resistor R8, the other end of the resistor R8 is respectively connected with one end of a resistor R9, a bar of the grounding resistor R10 and the base of a triode Q1, the emitter of a triode Q1 is connected with ground, the collector of the triode Q1 is respectively connected with one end of a primary coil of a transformer U1, one end of a capacitor C5, the other end of a resistor R4 and the other end of the resistor R5, The other end of the resistor R9, the other end of the primary coil of the transformer U1 and the other end of the capacitor C5 are all connected with a power supply of +5V, and the secondary coil of the transformer U1 outputs signals for the frequency-selecting amplifying circuit.
4. The integrated double-layer composite pipeline leakage detection system according to claim 1, wherein the differential output circuit comprises an operational amplifier AR2, an operational amplifier AR3 and a capacitor C6, the inverting input terminal of the operational amplifier AR3 and one end of the capacitor C6 are connected to one end of the secondary coil of the transformer U1, the non-inverting input terminal of the operational amplifier AR2 and the other end of the capacitor C6 are connected to the other end of the secondary coil of the transformer U1, the inverting input terminal of the operational amplifier AR2 is connected to the output terminal of the operational amplifier AR2 and one end of the resistor R11, the other end of the resistor R11 is connected to the non-inverting input terminal of the operational amplifier AR4 and one end of the resistor R13, the non-inverting input terminal of the operational amplifier AR3 is connected to the output terminal of the operational amplifier AR3 and one end of the resistor R12, the other end of the resistor R12 is connected to the inverting input terminal of the operational amplifier AR4 and one end of the ground resistor R14, the other end of the resistor R132 and the output end of the operational amplifier AR4 are connected with a host of the pipeline leakage detector.
5. The integrated double-layer composite pipeline leakage detection system according to claim 1, wherein the active noise reduction circuit comprises a capacitor C7, the left end of the capacitor C7 is connected with a noise signal, the right end of the capacitor C7 is respectively connected with the inverted input end of an operational amplifier AR5, one end of a resistor R16, one end of a resistor R17 and one end of a capacitor C9, the other end of a resistor R17 is respectively connected with one end of a resistor R18 and one end of a grounded capacitor C10, the other end of a capacitor C9 is respectively connected with one end of a grounded resistor R19 and one end of a capacitor C8, the non-inverted input end of the operational amplifier AR5 is connected with the ground, the output end of the operational amplifier AR5 is respectively connected with the other end of a resistor R16, the other end of a capacitor R18, the other end of a capacitor C8 and the negative electrode of a voltage regulator Z1, the positive electrode of a voltage regulator Z1 is connected with the anode of a thyristor VTL1, the cathode of the VTL1 is connected with the inverted input end of the operational amplifier AR4, the control electrode of the thyristor VTL1 is connected with the emitting electrode of the triode Q2, the collector electrode of the triode Q2 is connected with +5V of the power supply, the base electrode of the triode Q2 is connected with the anode of the voltage-regulator tube Z2 through a resistor R5, and the cathode of the voltage-regulator tube Z2 is connected with the output end of the operational amplifier AR 4.
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| CN202023266251.4U CN214037891U (en) | 2020-12-29 | 2020-12-29 | Integrated double-layer composite pipeline leakage detection system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116818795A (en) * | 2023-08-31 | 2023-09-29 | 中国地质大学（武汉） | Pipeline photoelectric nondestructive testing system |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116818795A (en) * | 2023-08-31 | 2023-09-29 | 中国地质大学（武汉） | Pipeline photoelectric nondestructive testing system |
| CN116818795B (en) * | 2023-08-31 | 2023-12-19 | 中国地质大学（武汉） | Pipeline photoelectric nondestructive testing system |
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