CN111610570A - Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof - Google Patents

Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof Download PDF

Info

Publication number
CN111610570A
CN111610570A CN202010610110.5A CN202010610110A CN111610570A CN 111610570 A CN111610570 A CN 111610570A CN 202010610110 A CN202010610110 A CN 202010610110A CN 111610570 A CN111610570 A CN 111610570A
Authority
CN
China
Prior art keywords
pin
point
observation
magnetotelluric
output end
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010610110.5A
Other languages
Chinese (zh)
Inventor
程辉
李帝铨
傅崧原
廖秀英
付国红
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hunan University of Science and Technology
Original Assignee
Hunan University of Science and Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hunan University of Science and Technology filed Critical Hunan University of Science and Technology
Priority to CN202010610110.5A priority Critical patent/CN111610570A/en
Publication of CN111610570A publication Critical patent/CN111610570A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
    • G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
    • G01V3/12—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with electromagnetic waves
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
    • G01R29/08—Measuring electromagnetic field characteristics
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/001—Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geophysics (AREA)
  • Measuring Magnetic Variables (AREA)

Abstract

The invention discloses a device and a method for investigating power frequency interference of a magnetotelluric remote reference point and an observation point thereof. The invention mainly comprises 2 pairs of grounding electrodes, wherein the 2 pairs of grounding electrodes are respectively connected with the impedance transformation circuits in the x direction and the y direction; the output end of the x-direction impedance conversion circuit is respectively connected with 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, the output end of each frequency point band-pass filter is respectively connected with 5-path control amplifiers, the output end of each control amplifier is respectively connected with 5-path wave detectors, and the output end of each wave detector is connected with an x-direction analog-to-digital converter; the connection mode behind the output end of the y-direction impedance transformation circuit is similar to that of the x-direction impedance transformation circuit, and the y-direction impedance transformation circuit is finally connected to a y-direction analog-to-digital converter; the output ends of the x and y analog-to-digital converters are connected with a single chip microcomputer, and the single chip microcomputer is connected with a display, a memory, keys and a communication interface. The invention provides power frequency interference background data for remote reference point setting, measuring network arrangement and observation data evaluation of the magnetotelluric sounding.

Description

Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof
Technical Field
The invention belongs to the technical field of exploration geophysical, and particularly relates to a device and a method for investigating power frequency interference of a magnetotelluric remote reference point and an observation point thereof.
Background
In the exploration of the electric method and the electromagnetic method, such as an electric sounding method, an electric sectioning method, a high-density electric method, a transient electromagnetic method, a ground penetrating radar, a controllable source audio frequency magnetotelluric method, an audio frequency magnetotelluric method, a magnetotelluric method and the like. According to the requirements of various methods, for example, the measuring point selected in technical specification DZ/T0173-1997 of magnetotelluric depth measurement method 4.1.6 should be far away from the electromagnetic interference source, and the following requirements are generally required: a. leave large factories, mines, electric railways and power stations for more than 2 Km; b. leave the broadcasting station and the radar station by more than 1 Km; c. 500m or more away from the high-voltage power line; d. leave the busy road for more than 200 m. The selection of the far reference point mainly comprises the steps of manually selecting an area with less human activities, observing the magnetotelluric observation equipment after the magnetotelluric observation equipment is laid, and analyzing a time waveform and a spectrogram by technicians to judge the power frequency electromagnetic interference intensity. And if no stronger power frequency periodic signal interference and impact signal interference are found within a certain time length, the point can be used for laying a far reference point. The technical regulation of controllable source audio magnetotelluric method promulgated draft stipulates: 5.1.3 surveying the conditions of terrain, landform, traffic, weather, residential points, vegetation and the like of the survey area on the spot, surveying the electromagnetic interference source of the survey area and estimating the electromagnetic interference condition (see appendix C); 5.3.5 the line should be kept away from high-voltage line and other power facilities, large villages and small towns, factory and mining areas, mountain peaks and narrow valleys; 5.5 Pre-production testing; the method comprises the steps of judging the characteristics of the type, the strength, the frequency distribution range, the interference time interval and the like of an electromagnetic interference source by actually measuring an electromagnetic interference signal of a measuring area, and providing a method basis for avoiding, reducing or suppressing the influence of an electromagnetic interference field; c2.1 detection of electromagnetic noise-before the technical design of the CSAMT method of working in the new area, should go on the spot and go on the investigation, know the cultural facilities near the observation point, judge the type, position and their working period of the electromagnetic interference source, can utilize portable wide band digital oscillograph, frequency spectrograph (or other portable apparatuses) to detect frequency distribution range and amplitude intensity of electromagnetic noise (E field and H field) of survey area, etc.; according to the electromagnetic noise information mastered by the reconnaissance or detection, the working area is determined to belong to which interference area, so that a reasonable working scheme is formulated for avoiding, reducing or suppressing the interference of the electromagnetic noise in the working area.
Carefully reading the procedures of the methods, the active method is to investigate the interference source, analyze the power frequency interference intensity in a test mode before production, and confirm the property and the frequency bandwidth of the interference source; the passive field method is far away from an interference source, but the requirements of the regulations on power frequency (single-phase and three-phase) interference intensity survey are fuzzy, and meanwhile, interference data are not quantized.
Disclosure of Invention
The first purpose of the present invention is to provide a magnetotelluric remote reference point and its observation point power frequency interference investigation apparatus for rapidly, simply and directly measuring power frequency and its harmonic interference strength, aiming at the above-mentioned defects existing in the prior art, and providing power frequency interference background data for the setting of the remote reference point, the network arrangement and the observation data evaluation in the design of the magnetotelluric depth measurement scheme.
The above object of the present invention is achieved by the following technical solutions:
the invention relates to a magnetotelluric far reference point and observation point power frequency interference investigation device, which comprises 2 pairs of ground electrodes Mx and Nx, My and Ny, wherein the 2 pairs of ground electrodes are respectively connected with an x-direction impedance transformation circuit and a y-direction impedance transformation circuit; the output end of the x-direction impedance conversion circuit is respectively connected with 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, the output end of each frequency point band-pass filter is respectively connected with x1, x2, x3, x4 and x5 program-controlled amplifiers, the output end of each frequency point program-controlled amplifier is respectively connected with x1, x2, x3, x4 and x5 detectors, and the output end of each frequency point detector is connected with an analog-to-digital converter in the x direction; the output end of the y-direction impedance conversion circuit is respectively connected with 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, and the output end of each frequency point band-pass filter is respectively connected with y1, y2, y3, y4 and y5 program-controlled amplifiers; the output end of each frequency point program control amplifier is respectively connected with y1, y2, y3, y4 and y5 detectors, and the output end of each frequency point detector is connected with an analog-to-digital converter in the y direction; after the analog-to-digital converters in the x direction and the y direction respectively complete the analog-to-digital conversion in the x direction and the y direction, the output end of the analog-to-digital converter is connected with the single chip microcomputer, and the single chip microcomputer is connected with a display, a memory, a key and a communication interface.
Specifically, the 2 pairs of ground electrodes are arranged in 2 orthogonal directions, respectively.
Specifically, the 2 pairs of grounded electrodes are either unpolarized electrodes or metal electrodes or conductive electrodes of other materials.
Specifically, the band-pass filters in the x and y directions both include R8, the left end of R8 is connected with the output end of the impedance transformation circuit, and the right end of R8 is connected with the left end of C1, the left end of C8, and the upper end of R11; the lower ends of R11 and R12 are grounded; the upper end of the R12 is connected with the non-inverting input end of the operational amplifier; the right end of the C1 is respectively connected with the upper end of the R5 and the output end of the operational amplifier; the right end of C8 is connected to the lower end of R5 and the inverting input of the operational amplifier.
Furthermore, the band-pass filters in the x direction and the y direction both comprise R8, the left end of R8 is connected with the output end of the impedance transformation circuit, and the right end of R8 is connected with the left end of C1, the left end of C8 and the upper end of R11; the lower ends of R11 and R12 are grounded; the upper end of the R12 is connected with the non-inverting input end of the operational amplifier; the right end of the C1 is respectively connected with the upper end of the R5 and the output end of the operational amplifier; the right end of C8 is connected to the lower end of R5 and the inverting input of the operational amplifier.
Specifically, the detector in the x and y directions comprises R2, and the left ends of R2 and R14 are connected with the output end of the programmable amplifier; the right end of the R2 is connected with the reverse end of the operational amplifier A, the anode of the diode D1 and the left end of the R1; the cathode of the diode D1 is connected with the output end of the operational amplifier A and the anode of the diode D2; the in-phase end of the operational amplifier A is connected with the upper end of the R7, and the lower end of the R7 is grounded; pin 4 of the operational amplifier A is connected with a-5V power supply, and pin 8 is connected with a +5V power supply; the right end of the R14 is connected with the non-inverting end of the operational amplifier B; the inverting end of the operational amplifier B is connected with the left end of the R10 and the anode of the diode D3; the cathode of the diode D3 is connected with the output end of the operational amplifier B and the anode of the diode D4, and the right end of R10, the right end of R1, the cathode of the diode D2 and the cathode of the diode D4 jointly form the output of the detector; the left end of R15 is connected with A point, the right end of R15 is connected with the upper end of C9, the lower end of C9 is grounded, and the right end of R15 and the upper end of C9 form low-pass filter to output X-V6.
Specifically, the 1 st pin of the analog-to-digital converter chip in the X direction is connected with a +5V power supply, the 2 nd pin is grounded, the 3 rd pin is connected with a reference signal VREFN, the 4 th pin is connected with a reference signal VREFP, the 5 th pin is grounded, the 6 th pin is connected with X-V6, the 7 th pin is connected with X-V7, the 8 th pin is connected with X-V8, the 9 th pin is connected with X-V9, and the 10 th pin is connected with X-V10; the 27 th pin is connected with the left end of the R16, and the right end of the R16 is connected with a PB8 port; the 24 th pin is connected with the left end of the R17, and the right end of the R17 is connected with a PB3 port; the 23 rd pin is connected with the left end of R18, and the right end of R18 is connected with a PB5 port; the 22 nd pin is connected with the left end of R19, and the right end of R19 is connected with a PB9 port; the 21 st pin is connected with the left end of R20, and the right end of R20 is connected with a PA3 port; the 20 th pin is connected with the left end of the R21, and the right end of the R21 is connected with a PA15 port; the 19 th pin is connected with the upper end of a crystal oscillator Y2 and the left end of a C10, the right end of C10 is connected with the right end of a C11 and grounded, and the left end of the C11 is connected with the lower end of a crystal oscillator Y2 and connected into the 18 th pin; the 17 th pin is grounded; the 16 th pin is connected with a +3.3V power supply; the pin connection of the analog-to-digital converter chip in the y direction is similar to the pin connection of the analog-to-digital converter chip in the x direction.
The second purpose of the invention is to provide a survey method based on the magnetotelluric remote reference point and observation point power frequency interference survey device, which comprises the following steps:
(1) carrying out long-time power frequency interference intensity observation on a far reference point of a planned selection point, wherein the observation scheme is to simultaneously observe 2 directions, the observation frequency points are 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, the observed quantity is the amplitude intensity of each frequency point, and energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 directions are obtained to form power frequency interference intensity information of a magnetotelluric far reference alternative point;
(2) carrying out certain time length or single-point observation on a preset observation point, wherein the observation scheme is that 2 directions of the observation point are observed simultaneously, the observation frequency points are 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, the observed quantity is the amplitude intensity on each frequency point, and energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 directions are obtained to form power frequency interference intensity information of the magnetotelluric observation point;
(3) the observation result obtained by the observation device forms energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic waves of a remote reference point and an observation point in magnetotelluric work, and forms an electromagnetic interference intensity background value of the alternative remote reference point and a preset observation point.
The invention utilizes two pairs of grounding electrodes to realize the requirement of measuring the power frequency and harmonic interference of the ground electric field in production practice, has the advantages of quickly and visually displaying the amplitude intensity of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, can carry out power frequency interference intensity investigation during previous investigation or survey, has simple and convenient measurement, saves manpower and material resources, and provides power frequency interference background noise data for making a reasonable working scheme for avoiding, reducing or suppressing the interference of electromagnetic noise in a working area.
In the field of electric (magnetic) method exploration, electromagnetic interference is considered as a main interference source in the production practice process, and various circuits are required to be designed for suppressing interference of power frequency fundamental waves and second and third harmonic waves of the power frequency fundamental waves in a traditional electric (magnetic) method exploration instrument. The invention is contrary to the prior art, the magnetotelluric far reference point and the observation point power frequency interference investigation device thereof are specially used for observing the intensities of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, and two paths of observation devices for observing the interference intensity measurement in the x and y directions in physical isolation are designed according to the working characteristics of an electromagnetic method, and through the rapid observation work of early investigation and survey of a production operation area, one-dimensional section diagrams and two-dimensional plane diagrams or time-intensity diagrams of the intensities of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz in the area can be formed, interference characteristic data are provided for method selection, interference suppression, observation data quality evaluation and the like in the subsequent scheme design, and the current situation that no first-hand measured data exists for the power frequency interference situation of the production operation area is solved.
Drawings
Fig. 1 is a schematic block diagram of an apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a field observation arrangement of an apparatus according to an embodiment of the present invention.
Fig. 3 is a circuit diagram of the band pass filter of fig. 1.
Fig. 4 is a circuit diagram of the detector of fig. 1.
Fig. 5 is a circuit diagram of the analog-to-digital converter of fig. 1.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Referring to fig. 1, the magnetotelluric remote reference point and observation point power frequency interference investigation apparatus of the embodiment of the present invention includes 2 pairs of ground electrodes Mx、MyAnd Nx、NyThe ground electrode is either a non-polarized electrode or a metal electrode or a conductive electrode of other material. As can be seen from fig. 1, the grounding electrode pairs in the x and y directions are connected with respective impedance transformation circuits; the output end of the impedance transformation circuit in the x direction is respectively connected with the input ends of the 50Hz, 100Hz, 150Hz, 300Hz and 600Hz five-way band-pass filters, wherein the output end of the 50Hz band-pass filter is connected with the program control amplifier x1, and the output end of the program control amplifier x1 is connected with the input end of the detector x 1; the output end of the 100Hz band-pass filter is connected with the input end of a program control amplifier x2, and the output end of a program control amplifier x2 is connected with the input end of a detector x 2; the output end of the 150Hz band-pass filter is connected with the input end of a program control amplifier x3, and the output end of a program control amplifier x3 is connected with the input end of a detector x 3; the output end of the 300Hz band-pass filter is connected with the input end of a program control amplifier x4, and the output end of a program control amplifier x4 is connected with the input end of a detector x 4; the output end of the 600Hz band-pass filter is connected with the input end of a program control amplifier x5, and the output end of a program control amplifier x5 is connected with the input end of a detector x 5; the output ends of the detectors x1, x2, x3, x4 and x5 are simultaneously connected with the analog-to-digital converter in the x direction, and the output end of the analog-to-digital converter in the x direction is connected with the single chip microcomputer.
Referring to fig. 1, the output end of the impedance transformation circuit in the y direction is respectively connected with the input ends of corresponding five-way band-pass filters of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, wherein the output end of the 50Hz band-pass filter is connected with the input end of the program control amplifier y1, and the output end of the program control amplifier y1 is connected with the input end of the detector y 1; the output end of the 100Hz band-pass filter is connected with the input end of the program control amplifier y2, and the output end of the program control amplifier y2 is connected with the input end of the detector y 2; the output end of the 150Hz band-pass filter is connected with the input end of the program control amplifier y3, and the output end of the program control amplifier y3 is connected with the input end of the detector y 3; the output end of the 300Hz band-pass filter is connected with the input end of the program control amplifier y4, and the output end of the program control amplifier y4 is connected with the input end of the detector y 4; the output end of the 600Hz band-pass filter is connected with the input end of the program control amplifier y5, and the output end of the program control amplifier y5 is connected with the input end of the detector y 5; the output ends of the detectors y1, y2, y3, y4 and y5 are connected with an analog-to-digital converter in the y direction, the output end of the analog-to-digital converter in the y direction is connected with a single chip microcomputer, and the single chip microcomputer is connected with a display, a memory, keys and a communication interface.
Fig. 2 is a schematic view of the field observation arrangement according to the embodiment of the invention. Wherein, one direction is defined as x direction and the vertical direction is defined as y direction during work. Ground electrodes Mx, Nx are arranged in the x direction; and grounding electrodes My and Ny are arranged in the y direction, and the acquired ground electric field information is transmitted to the observation device through a lead.
The signal being supplied by two pairs of earthed electrodes Mx、MyAnd Nx、NyPicking up, filtering out signals with central frequencies of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz by band-pass filtering through impedance conversion connected with each other, and sending the signals to an analog-to-digital converter after program control amplification and precise detection; and sending the result of the analog-to-digital conversion to a single chip for processing, displaying and storing the measurement result to obtain observation data of the power frequency interference intensity of the measurement point.
Referring to fig. 3, a circuit diagram of the 50Hz, 100Hz, 150Hz, 300Hz, 600Hz band-pass filters of fig. 1 is shown. The left end of R8 is connected with the output end of the impedance transformation circuit, and the right end of R8 is connected with the left end of C1, the left end of C8 and the upper end of R11; the lower ends of R11 and R12 are grounded; the upper end of the R12 is connected with the non-inverting input end of the operational amplifier; the right end of the C1 is respectively connected with the upper end of the R5 and the output end of the operational amplifier; the right end of C8 is connected to the lower end of R5 and the inverting input of the operational amplifier. According to the circuit shown in fig. 3, the center frequency, Q value and gain of the band-pass filter required by the frequency point can be set by calculating and selecting the corresponding resistors R5, R8 and R11 and the corresponding capacitors C1 and C8.
Referring to fig. 4, a circuit diagram of all detectors of fig. 1 is shown. As can be seen from FIG. 3, the left end of R2 and the left end of R14 are connected with the output ends of the programmable amplifiers of each path (5 paths including 50Hz, 100Hz, 150Hz, 300Hz and 600 Hz); the right end of the R2 is connected with the reverse end of the operational amplifier A, the anode of the diode D1 and the left end of the R1; the cathode of the diode D1 is connected with the output end of the operational amplifier A and the anode of the diode D2; the in-phase end of the operational amplifier A is connected with the upper end of the R7, and the lower end of the R7 is grounded; pin 4 of the operational amplifier A is connected with a-5V power supply, and pin 8 is connected with a +5V power supply; the right end of the R14 is connected with the non-inverting end of the operational amplifier B; the inverting end of the operational amplifier B is connected with the left end of the R10 and the anode of the diode D3; the cathode of the diode D3 is connected with the output end of the operational amplifier B and the anode of the diode D4, and the right end of R10, the right end of R1, the cathode of the diode D2 and the cathode of the diode D4 jointly form the output of the detection circuit; and the direct current level signal with low ripple coefficient is obtained by RC low-pass filtering and is output to an analog-to-digital converter, namely the left end of R15 is connected with A point, the right end of R15 is connected with the upper end of C9, the lower end of C9 is grounded, the right end of R15 and the upper end of C9 form a low-pass filter, and the detection output signal is output by V6 after pulse components are filtered by R15 and C9. Each path of signal is sent to the input end of the corresponding analog-to-digital converter after being detected.
Fig. 5 is a circuit diagram of the analog-to-digital converter x and the analog-to-digital converter y in fig. 1. As can be seen from fig. 5, the signals observed in the x and y directions after passing through the detectors x1, x2, x3, x4, x5, y1, y2, y3, y4, and y5 are sent to the analog-to-digital converters x and y for processing the signals in the x and y directions, respectively. Taking the module converter x of the x-direction signal as an example: the 1 st pin of an analog-digital converter X chip is connected with a +5V power supply, the 2 nd pin is grounded, the 3 rd pin is connected with a reference signal VREFN, the 4 th pin is connected with a reference signal VREFP, the 5 th pin is grounded, the 6 th pin is connected with X-V6, the 7 th pin is connected with X-V7, the 8 th pin is connected with X-V8, the 9 th pin is connected with X-V9, and the 10 th pin is connected with X-V10; the 27 th pin is connected with the left end of the R16, and the right end of the R16 is connected with a PB8 port; the 24 th pin is connected with the left end of the R17, and the right end of the R17 is connected with a PB3 port; the 23 rd pin is connected with the left end of R18, and the right end of R18 is connected with a PB5 port; the 22 nd pin is connected with the left end of R19, and the right end of R19 is connected with a PB9 port; the 21 st pin is connected with the left end of R20, and the right end of R20 is connected with a PA3 port; the 20 th pin is connected with the left end of the R21, and the right end of the R21 is connected with a PA15 port; the 19 th pin is connected with the upper end of a crystal oscillator Y2 and the left end of a C10, the right end of C10 is connected with the right end of a C11 and grounded, and the left end of the C11 is connected with the lower end of a crystal oscillator Y2 and connected into the 18 th pin; the 17 th pin is grounded; the 16 th pin is connected with a +3.3V power supply. The pin connections of the analog-to-digital converter chip in the y-direction are similar to the pin connections of the analog-to-digital converter chip in the x-direction and will not be described in detail here.
In this embodiment, the investigation method based on the above apparatus includes the following steps:
(1) carrying out power frequency interference intensity observation for a long time (observation time is continuous recording of more than 1 hour) on a far reference point of a planned selection point, wherein the observation scheme is to simultaneously observe 2 orthogonal directions, observe frequency points of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, observe amplitude intensity on each frequency point, obtain energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 orthogonal directions and form power frequency interference intensity information of a magnetotelluric far reference selection point;
(2) carrying out certain time length or single-point observation on a preset observation point (the continuous observation time is about 5-10 minutes, and single-point observation is carried out for 1 time), wherein the observation scheme is that 2 orthogonal directions of the observation point are observed simultaneously, the observation frequency points are 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, the observed quantity is the amplitude intensity on each frequency point, and the energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 orthogonal directions are obtained to form power frequency interference intensity information of the magnetotelluric observation point;
(3) the observation result obtained by the observation device forms energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic waves of a remote reference point and an observation point in magnetotelluric work, and forms an electromagnetic interference intensity background value of the alternative remote reference point and a preset observation point.
The operation steps of the device applying the embodiment are as follows:
and respectively sending electric field signals between the two pairs of grounding points picked by the two pairs of grounding electrodes to the x-direction impedance transformation circuit and the y-direction impedance transformation circuit for impedance transformation.
The output ends of the X-direction path impedance transformation circuit and the y-direction path impedance transformation circuit are respectively connected with the input ends of corresponding 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, each band-pass filter selects the central frequency of the filter and frequency signals nearby the central frequency of the filter and then performs controlled amplification, and the output end of the controlled amplifier is connected with the precision detector.
Detecting positive polarity signals by 5 groups of precision detectors in the X direction, sending the positive polarity signals to an analog-to-digital converter for analog-to-digital conversion after RC smooth filtering, and sending converted digital signals to a single chip microcomputer for processing to obtain a power frequency interference signal measured value of a grounding electrode in the X direction; and 5 groups of precision detectors in the y direction detect positive polarity signals, the positive polarity signals are subjected to RC smooth filtering and then are sent to an analog-to-digital converter for analog-to-digital conversion, and converted digital signals are sent to a single chip microcomputer for processing to obtain a power frequency interference signal measured value of the y-direction grounding electrode.
The single chip microcomputer processes the result, displays the result on the display, simultaneously stores the result on the local memory, and can also communicate with the upper computer to transmit the measurement result.
The invention can simultaneously observe the amplitudes of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz in the earth electric field in 1 direction or 2 directions, obtain the amplitude intensity values of 50Hz, 100Hz, 150Hz, 300Hz and 600Hz in the earth electric field through the grounding electrode, and simultaneously observe the amplitude intensity values of frequencies in more than two directions of x and y to form a power frequency interference intensity one-dimensional profile curve of an electrical (magnetic) method preset measuring line in an exploration area, further form a power frequency interference intensity two-dimensional plane diagram of an electrical (electromagnetic) method preset area in the exploration area, and provide data reporting services for early evaluation, engineering scheme and later evaluation of geophysical exploration; meanwhile, the electromagnetic interference evaluation can be performed on the far reference point in the earth electromagnetic sounding work, and the data of the interference signal of the corresponding frequency point is provided for the selection of the far reference point.
In addition, in countries or regions where the operating frequency of the power grid is 60Hz, the central frequency parameter of the band-pass filter in the measuring device is modified or switched, so that the frequency amplitude intensity observation can be realized, and therefore, the device and the method for measuring the amplitude intensity of 60Hz, 120 Hz, 180 Hz, 360 Hz and 720Hz by using the principle of the invention are also within the protection scope of the invention.

Claims (9)

1. A magnetotelluric far reference point and observation point power frequency interference investigation device, its characterized in that: the device comprises 2 pairs of grounding electrodes Mx, Nx, My and Ny, wherein the 2 pairs of grounding electrodes are respectively connected with an x-direction impedance transformation circuit and a y-direction impedance transformation circuit; the output end of the x-direction impedance conversion circuit is respectively connected with 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, the output end of each frequency point band-pass filter is respectively connected with x1, x2, x3, x4 and x5 program-controlled amplifiers, the output end of each frequency point program-controlled amplifier is respectively connected with x1, x2, x3, x4 and x5 detectors, and the output end of each frequency point detector is connected with an analog-to-digital converter in the x direction; the output end of the y-direction impedance conversion circuit is respectively connected with 50Hz, 100Hz, 150Hz, 300Hz and 600Hz band-pass filters, and the output end of each frequency point band-pass filter is respectively connected with y1, y2, y3, y4 and y5 program-controlled amplifiers; the output end of each frequency point program control amplifier is respectively connected with y1, y2, y3, y4 and y5 detectors, and the output end of each frequency point detector is connected with an analog-to-digital converter in the y direction; after the analog-to-digital converters in the x direction and the y direction respectively complete the analog-to-digital conversion in the x direction and the y direction, the output end of the analog-to-digital converter is connected with the single chip microcomputer, and the single chip microcomputer is connected with a display, a memory, a key and a communication interface.
2. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, wherein: the 2 pairs of ground electrodes are arranged in 2 orthogonal directions, respectively.
3. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, wherein: the 2 pairs of grounded electrodes are either unpolarized electrodes or metal electrodes or conductive electrodes of other materials.
4. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, wherein: the band-pass filters in the x direction and the y direction respectively comprise R8, the left end of R8 is connected with the output end of the impedance transformation circuit, and the right end of R8 is connected with the left end of C1, the left end of C8 and the upper end of R11; the lower ends of R11 and R12 are grounded; the upper end of the R12 is connected with the non-inverting input end of the operational amplifier; the right end of the C1 is respectively connected with the upper end of the R5 and the output end of the operational amplifier; the right end of C8 is connected to the lower end of R5 and the inverting input of the operational amplifier.
5. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 4, wherein: the parameters of the band-pass filter in the x and y directions are that the center frequency of the 50Hz band-pass filter is 50Hz, the bandwidth is from 45Hz to 55Hz, and the total bandwidth is 10 Hz; the center frequency of the 100Hz band-pass filter is 100Hz, the bandwidth is from 95Hz to 105Hz, and the bandwidth is 10 Hz; the center frequency of the 150Hz band-pass filter is 150Hz, the bandwidth is 142.5Hz to 157.5Hz, and the bandwidth is 15 Hz; the center frequency of the 300Hz band-pass filter is 300Hz, the bandwidth is 290Hz to 310Hz, and the bandwidth is 20 Hz; the 600Hz band-pass filter has a center frequency of 600Hz and a bandwidth of 590Hz to 610Hz, which is a 20Hz bandwidth.
6. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, wherein: the detector in the x direction and the y direction comprises R2, and the left end of R2 and the left end of R14 are connected with the output end of the programmable amplifier; the right end of the R2 is connected with the reverse end of the operational amplifier A, the anode of the diode D1 and the left end of the R1; the cathode of the diode D1 is connected with the output end of the operational amplifier A and the anode of the diode D2; the in-phase end of the operational amplifier A is connected with the upper end of the R7, and the lower end of the R7 is grounded; pin 4 of the operational amplifier A is connected with a-5V power supply, and pin 8 is connected with a +5V power supply; the right end of the R14 is connected with the non-inverting end of the operational amplifier B; the inverting end of the operational amplifier B is connected with the left end of the R10 and the anode of the diode D3; the cathode of the diode D3 is connected with the output end of the operational amplifier B and the anode of the diode D4, and the right end of R10, the right end of R1, the cathode of the diode D2 and the cathode of the diode D4 jointly form the output of the detector; the left end of R15 is connected with A point, the right end of R15 is connected with the upper end of C9, the lower end of C9 is grounded, and the right end of R15 and the upper end of C9 form low-pass filter to output X-V6.
7. The magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, wherein: the 1 st pin of the analog-to-digital converter chip in the X direction is connected with a +5V power supply, the 2 nd pin is grounded, the 3 rd pin is connected with a reference signal VREFN, the 4 th pin is connected with a reference signal VREFP, the 5 th pin is grounded, the 6 th pin is connected with X-V6, the 7 th pin is connected with X-V7, the 8 th pin is connected with X-V8, the 9 th pin is connected with X-V9, and the 10 th pin is connected with X-V10; the 27 th pin is connected with the left end of the R16, and the right end of the R16 is connected with a PB8 port; the 24 th pin is connected with the left end of the R17, and the right end of the R17 is connected with a PB3 port; the 23 rd pin is connected with the left end of R18, and the right end of R18 is connected with a PB5 port; the 22 nd pin is connected with the left end of R19, and the right end of R19 is connected with a PB9 port; the 21 st pin is connected with the left end of R20, and the right end of R20 is connected with a PA3 port; the 20 th pin is connected with the left end of the R21, and the right end of the R21 is connected with a PA15 port; the 19 th pin is connected with the upper end of a crystal oscillator Y2 and the left end of a C10, the right end of C10 is connected with the right end of a C11 and grounded, and the left end of the C11 is connected with the lower end of a crystal oscillator Y2 and connected into the 18 th pin; the 17 th pin is grounded; the 16 th pin is connected with a +3.3V power supply; the pin connection of the analog-to-digital converter chip in the y direction is similar to the pin connection of the analog-to-digital converter chip in the x direction.
8. An investigation method based on the magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 1, characterized by comprising the following steps:
(1) carrying out long-time power frequency interference intensity observation on a far reference point of a planned selection point, wherein the observation scheme is to simultaneously observe 2 directions, the observation frequency points are 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, the observed quantity is the amplitude intensity of each frequency point, and energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 directions are obtained to form power frequency interference intensity information of a magnetotelluric far reference alternative point;
(2) carrying out certain time length or single-point observation on a preset observation point, wherein the observation scheme is that 2 directions of the observation point are observed simultaneously, the observation frequency points are 50Hz, 100Hz, 150Hz, 300Hz and 600Hz, the observed quantity is the amplitude intensity on each frequency point, and energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic frequencies in the 2 directions are obtained to form power frequency interference intensity information of the magnetotelluric observation point;
(3) the observation result obtained by the observation device forms energy spectrums of single-phase and three-phase power frequency fundamental waves and partial harmonic waves of a remote reference point and an observation point in magnetotelluric work, and forms an electromagnetic interference intensity background value of the alternative remote reference point and a preset observation point.
9. The investigation method of the magnetotelluric remote reference point and observation point power frequency interference investigation device of claim 8, wherein the method comprises the following steps: the 2 directions are 2 orthogonal directions.
CN202010610110.5A 2020-06-30 2020-06-30 Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof Pending CN111610570A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010610110.5A CN111610570A (en) 2020-06-30 2020-06-30 Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010610110.5A CN111610570A (en) 2020-06-30 2020-06-30 Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof

Publications (1)

Publication Number Publication Date
CN111610570A true CN111610570A (en) 2020-09-01

Family

ID=72195025

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010610110.5A Pending CN111610570A (en) 2020-06-30 2020-06-30 Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof

Country Status (1)

Country Link
CN (1) CN111610570A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117538944A (en) * 2023-11-24 2024-02-09 长江大学 Picking method of magnetotelluric power spectrum

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117538944A (en) * 2023-11-24 2024-02-09 长江大学 Picking method of magnetotelluric power spectrum
CN117538944B (en) * 2023-11-24 2024-04-05 长江大学 Picking method of magnetotelluric power spectrum

Similar Documents

Publication Publication Date Title
JP5749920B2 (en) Ground resistance measurement device using remote control
CN105484740B (en) A kind of multifrequency detection device for being used to detect stratum complex resistivity
CN103235168B (en) Measuring system for shunt vectors of metal frames of large ground grids on basis of wireless transmission
CN103197133B (en) A kind of shunting of the large ground network based on wireless transmission vector quantity measurement method
CN104678229B (en) A kind of grounding net of transformer substation corrosion monitoring system
CN201138368Y (en) Defect diagnostic equipment for substation grounding grid
CN111179529A (en) Power cable prevents destroying early warning system
CN102680804A (en) Lightning electric field change signal measuring system and method
CN111610570A (en) Magnetotelluric far reference point and observation point power frequency interference investigation device and method thereof
CN111610230A (en) Rock and ore specimen electrical parameter measuring device and using method
CN102818928A (en) Current probe-based on-line measuring system for high-frequency corona pulse current on high-voltage line
CN206074741U (en) A kind of detection circuit for grounding net defect diagnosis
CN107741541A (en) A kind of rail traffic vehicles built-in field intensity near-field test method and system
CN110736904A (en) oiled paper insulation partial discharge monitoring device
CN212410881U (en) Magnetotelluric far reference point and observation point power frequency interference investigation device thereof
Liu et al. A magnetic detecting and evaluation method of substation’s grounding grids with break and corrosion
CN206804798U (en) A kind of built-in very high frequency(VHF) partial discharge detection device
CN210376520U (en) Multi-frequency scanning tower grounding resistance measuring device
CN202256507U (en) Grounding resistance monitoring device
CN116593842A (en) Cable partial discharge detection system and method with broadband and filtering functions
CN204166047U (en) A kind of lightning induced voltage sensor based on D-dot principle and measuring system
CN107270954B (en) A kind of vibrating string type sensor performance evaluation device and method
CN203164267U (en) Large-scale grounding grid metal framework shunt vector measuring system based on wireless transmission
CN105911594A (en) ZH-8 type multi-functional electrical workstation
Yao et al. Transmission line insulator fault detection based on ultrasonic technology

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination