CN111290029B - Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof - Google Patents

Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof Download PDF

Info

Publication number
CN111290029B
CN111290029B CN202010228923.8A CN202010228923A CN111290029B CN 111290029 B CN111290029 B CN 111290029B CN 202010228923 A CN202010228923 A CN 202010228923A CN 111290029 B CN111290029 B CN 111290029B
Authority
CN
China
Prior art keywords
coil
bucking
transmitting coil
compensation
transmitting
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.)
Active
Application number
CN202010228923.8A
Other languages
Chinese (zh)
Other versions
CN111290029A (en
Inventor
林君
陈健
张洋
皮帅
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.)
Jilin University
Original Assignee
Jilin University
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 Jilin University filed Critical Jilin University
Priority to CN202010228923.8A priority Critical patent/CN111290029B/en
Publication of CN111290029A publication Critical patent/CN111290029A/en
Application granted granted Critical
Publication of CN111290029B publication Critical patent/CN111290029B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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
    • G01V3/08—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices
    • G01V3/10—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Electromagnetism (AREA)
  • Environmental & Geological Engineering (AREA)
  • Geology (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Geophysics (AREA)
  • Geophysics And Detection Of Objects (AREA)

Abstract

A non-coplanar locking compensated dragging type electromagnetic device and a manufacturing method relate to the field of geophysical exploration electromagnetic method detection, and the device comprises a transient electromagnetic system host, a transmitting coil, a locking compensation coil, a receiving coil and a movable loading platform, wherein the transmitting coil, the receiving coil and the locking compensation coil are not coplanar with the central axis; the Bucking compensation coil is connected with the transmitting coil in series, the winding direction of the Bucking compensation coil is opposite to that of the transmitting coil, and the Bucking compensation coil is positioned above the receiving coil; the invention solves the technical problems of detection blind area, primary field coupling interference and low detection efficiency of the current transient electromagnetic small-size central loop detection device.

Description

Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof
Technical Field
The invention relates to the field of geophysical exploration electromagnetic method detection, in particular to a non-coplanar Bucking compensated dragging type electromagnetic device applied to urban underground geological detection and a manufacturing method thereof.
Background
With the gathering of urban population, the utilization rate of urban land resources is more and more tense, and the development and utilization of underground spaces and the safe operation related to the underground spaces become important problems to be solved urgently in large and medium-sized cities in China. To achieve safe and efficient use of the underground space, the geological structure of the underground space must first be probed. As an important geophysical exploration method, the ground transient electromagnetic method has the advantages of large detection depth, convenient working mode and the like in urban underground space detection compared with methods such as shallow earthquake, ground penetrating radar and the like. The transient electromagnetic center loop device has the advantages of large induction amplitude to underground abnormity, high transverse resolution and the like, is a preferred loop device suitable for urban underground space, is limited by urban road measurement environment, and needs a transient electromagnetic small-size detection coil. At this time, the receiving coil and the transmitting coil are relatively close to each other and are seriously interfered by the primary field, and measures must be taken for compensation.
In the traditional aviation transient electromagnetic method, a Bucking compensation coil is introduced for a central loop device, namely a reverse transmitting coil is added between the surfaces of a receiving coil and a transmitting coil, so that the primary field coupling effect at the receiving coil is weakened, the receiving amplifier is prevented from being saturated, and the near-field effect caused by the Bucking compensation coil can be ignored in high altitude. However, when the method is applied to a ground small-size detection coil, a near-zone effect is inevitably brought, namely, due to the introduction of a Bucking compensation coil, the stratum close to a receiving coil has almost no secondary field response, and a theoretical detection blind zone is brought. For urban road environment, shallow geology often contains abnormal bodies such as pipelines and cables, higher shallow detection resolution is needed, and the detection efficiency of traditional transient electromagnetic manual mobile detection is low. Therefore, the research on the transient electromagnetic detection technology with shallow layer, no blind area, low primary field coupling and high detection efficiency is of great significance.
Disclosure of Invention
The invention aims to provide a non-coplanar Bucking compensated towed electromagnetic device and a manufacturing method thereof, aiming at the defects of the prior art, and solving the technical problems of detection blind area, primary field coupling interference and low detection efficiency of the current transient electromagnetic small-size central loop detection coil by introducing a movable loading platform and optimizing the relative position of the detection coil.
The purpose of the invention is realized by the following technical scheme:
the invention provides a non-coplanar Bucking compensated dragging type electromagnetic device, which is characterized by comprising the following components: the device comprises a transient electromagnetic system host, a transmitting coil, a packing compensating coil, a receiving coil and a movable loading platform, wherein the transient electromagnetic system host is arranged on the movable loading platform and is respectively connected with the transmitting coil and the receiving coil, and the transient electromagnetic system host is used for supplying a pulse current signal to the transmitting coil and simultaneously receiving primary field induction voltage information fed back by the receiving coil; the transmitting coil is fixed on the table top of the movable loading platform, the transmitting coil is positioned below the receiving coil and the packing compensating coil, and the transmitting coil, the receiving coil and the packing compensating coil are not coplanar with the same central axis; the Bucking compensation coil is connected with the transmitting coil in series, the winding direction of the Bucking compensation coil is opposite to that of the transmitting coil, the Bucking compensation coil is positioned above the receiving coil, and the Bucking compensation coil is fixed on the movable loading platform through an insulating support; the receiving coil is arranged between the transmitting coil and the Bucking compensation coil and is fixed on the movable loading platform through an insulating support; the movable loading platform is an insulating platform.
Furthermore, the transmitting coil is made into a multi-turn square loop by winding a copper enameled wire, and the side length of the transmitting coil is smaller than the width of an urban road.
Further, the Bucking compensation coil is made into a single-turn square loop by winding a copper enameled wire, and the side length of the Bucking compensation coil is 0.2-0.3 times of that of the transmitting coil.
Furthermore, the receiving coil is made into a multi-turn square loop by winding a copper enameled wire, and the side length of the receiving coil is less than or equal to 0.3 time of that of the transmitting coil.
The non-coplanar Bucking compensated dragging type electromagnetic device is characterized in that: and when the transmitting coil is wound, a section is reserved for reversely winding the packing compensation coil, and the connecting section of the transmitting coil and the packing compensation coil (3) is wound in a twisted pair mode.
The invention also provides a method for manufacturing the non-coplanar Bucking compensated towed electromagnetic device, which is characterized by comprising the following steps of:
s1, clockwise winding a copper enameled wire into side length a, wherein the number of turns is NaThe square coil is arranged, a certain amount of copper wire allowance is reserved, a transmitting coil is obtained, the transmitting coil is placed in the center of a movable loading platform, and the height of the movable loading platform from the ground is h0；
S2, coaxially and reversely winding the residual copper enameled wire of the transmitting coil at a position h above the transmitting coil to form a side length b, wherein the number of turns is NbThe packing compensation coil is obtained by the square coil;
s3, winding the receiving coil to be side length c, and winding the receiving coil to be NcThe square coil is coaxially fixed between the transmitting coil and the Bucking compensation coil, and the distance between the receiving coil and the transmitting coil is hacThe distance between the receiving coil and the Bucking compensation coil is hbcRice, h ═ hac+hbc；
Wherein, the distance h between the Bucking compensation coil and the transmitting coil is obtained by the following method:
the magnetic field strength of the ground coaxial position point is determined according to the fact that the ratio of the magnetic field strength of the ground coaxial position point to the magnetic field strength of the ground coaxial position point is larger than 0.9 when the Bucking compensation coil and the transmitting coil are introduced, and the following formula is met:
Ba(h0)-Bb(h0+h)≥0.9Ba(h0)
wherein B isa(h0) Magnetic field strength in the vertical direction, h, at the point where the ground position of the transmitting coil is located in the direction of the central axis0Is the vertical distance between the transmitting coil and the ground, which is a known quantity; b isb(h0+ h) is the magnetic field strength of the Bucking compensation coil in the vertical direction at the point where the ground position is located along the central axis direction;
according to the Bio savart law, the magnetic field intensity B at the position d on the central axis of the square current-carrying coil with the side length of 2rz(d) Satisfies the following conditions:
Figure BDA0002428670150000031
wherein I is the current of the square coil, d is the distance from the center point of the plane of the square coil along the central axis, and μ0Is a vacuum magnetic conductivity; substituting the size distance parameters of the transmitting coil and the packing compensating coil into the formula, so that the distance h between the packing compensating coil and the transmitting coil can be determined;
wherein, the distance h between the receiving coil and the transmitting coilacAnd the distance h between the receiving coil and the Bucking compensation coilbcThe method for determining the value comprises the following steps:
calculating the side length a and the number of turns N by utilizing a Noemann formulaaThe length of the opposite side of the transmitting coil is c, the number of turns is NcMutual inductance coefficient M of receiving coilac
Figure BDA0002428670150000041
In the formula xa、yaCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil; x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil; f (x)a,xc) And f (y)a,yc) For the line element integral coefficient, the following equation is satisfied:
Figure BDA0002428670150000042
Figure BDA0002428670150000043
② calculating the side length size b and the number of turns N in the same waybThe mutual inductance coefficient M of the Bucking compensation coil to the receiving coilbcIs composed of
Figure BDA0002428670150000044
Figure BDA0002428670150000045
Figure BDA0002428670150000046
In the formula xb、ybCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil; x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil;
utilizing h as hac+hbcUnder known conditions, the proper M can be obtained through the integral formulaac＝MbcWhile the distance h between the receiving coil and the transmitting coilacAnd the distance h between the receiving coil and the Bucking compensation coilbcThe parameters obtained at this time can make the receiving coil in a primary field zero coupling state.
Through the design scheme, the invention can bring the following beneficial effects: the invention provides a non-coplanar Bucking compensated towed electromagnetic device and a manufacturing method thereof, which comprises the steps of firstly determining the sizes of a transmitting coil, a Bucking compensation coil and a receiving coil according to design requirements, obtaining the position of the Bucking compensation coil with negligible near-field effect according to the BioSaval's law, calculating the position of the best receiving coil by utilizing the mutual inductance coefficient between the coils, and in the actual operation, finely adjusting the position of the receiving coil up and down to compensate errors caused by inaccurate size design so that the receiving coil is easier to be positioned at a primary field zero coupling position. The invention can reduce the primary field coupling interference of the receiving coil, simultaneously can ensure that the near-zone effect brought by the compensating coil is negligible, the loss of the overall downward transmitting magnetic moment of the detecting coil is small, the zero coupling state of the receiving coil is relatively better adjusted due to the non-coplanar design, and in addition, the design of the dragging type movable loading platform ensures that the field detection efficiency is higher, thereby having greater practical application value.
Drawings
FIG. 1 is a schematic structural diagram of a non-coplanar Bucking compensated towed electromagnetic apparatus according to an embodiment of the present invention;
FIG. 2 is a flow chart illustrating the fabrication of a non-coplanar Bucking compensated towed electromagnetic apparatus according to an embodiment of the present invention;
FIG. 3 is a flowchart illustrating the testing of the non-coplanar Bucking compensated towed electromagnetic apparatus according to an embodiment of the present invention.
In the figure: 1-a transient electromagnetic system host; 2-a transmitting coil; 3-Bucking compensation coils; 4-a receiving coil; 5-a movable loading platform; 6-plastic table posts; 7-twisted pair.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Fig. 1 shows a schematic structural diagram of a non-coplanar Bucking compensated towed electromagnetic apparatus of the present invention, which includes a transient electromagnetic system main machine 1, a transmitting coil 2, a Bucking compensation coil 3, a receiving coil 4, and a movable loading platform 5.
The transient electromagnetic system host 1 integrates a transmitting system and a receiving system of transient electromagnetism, has a human-computer interaction interface, can set transmitting current, transmitting frequency, transmitting waveform and receiving sampling rate, and simultaneously has a large-capacity storage space for storing collected data; the transient electromagnetic system host 1 is respectively connected with the transmitting coil 2 and the receiving coil 4, and the transient electromagnetic system host 1 is used for supplying pulse current signals to the transmitting coil 2 and receiving primary field induced voltage information fed back by the receiving coil 4.
The transmitting coil 2 is made into a multi-turn square loop by winding a copper enameled wire, the transmitting coil 2 is fixed on a table top of the movable loading platform 5 and is positioned below the receiving coil 4 and the packing compensating coil 3, the transmitting coil, the receiving coil 4 and the packing compensating coil 3 are not coplanar with each other on the same central axis, the side length of the transmitting coil 2 is smaller than the width of an urban road (smaller than 2.3m), and the side length of the transmitting coil 2 is selected to be 2m in the embodiment.
The packing compensation coil 3 is wound by adopting a copper enameled wire to form a single-turn square loop, the packing compensation coil 3 is connected with the transmitting coil 2 in series, the winding direction of the packing compensation coil 3 is opposite to that of the transmitting coil 2, the packing compensation coil 3 is positioned above the receiving coil 4, and the packing compensation coil 3 is fixed on the movable loading platform 5 through a plastic table column 6; the side length of the Bucking compensation coil 3 is 0.2-0.3 times of the side length of the transmitting coil 2, and the side length of the Bucking compensation coil 3 is selected to be 0.56m in the embodiment.
The receiving coil 4 is made into a multi-turn square loop by winding a copper enameled wire, is placed between the transmitting coil 2 and the packing compensation coil 3 and is fixed through a plastic table post 6, so that the receiving coil 4 is in a relatively uniform area, the side length of the receiving coil 4 is generally not more than 0.3 time of that of the transmitting coil 2, and the side length of the receiving coil 4 is selected to be 0.3m in the embodiment.
The movable loading platform 5 is a movable insulated plastic loading platform and is used for loading the whole transient electromagnetic system, the platform surface of the movable loading platform 5 is used for fixing the transient electromagnetic system host 1 and the transmitting coil 2, and the locking compensation coil 3 and the receiving coil 4 are fixed through a plastic platform column 6 on the movable loading platform 5.
The Bucking compensation coil 3 is generally used for reserving one section for reversely winding the non-coplanar Bucking compensation coil 3 when the transmitting coil 2 is wound, and the connecting section of the transmitting coil 2 and the Bucking compensation coil 3 is wound in a twisted pair 7 mode.
Referring to fig. 2, a device fabrication flow diagram is shown, comprising the steps of:
s1, placing the transmitting coil 2 in the center of a movable loading platform 5, wherein the movable loading platform 5 is h away from the ground0Clockwise winding the copper enameled wire to the side length dimension a of 2m and the number of turns of NaA certain copper wire allowance is reserved for the square coil of 4;
s2, coaxially and reversely winding a packing compensation coil 3 with a single turn and a side length of 0.56m by the remaining copper wire of the transmitting coil 2 at a position h above the transmitting coil 2;
s3, similarly, the receiving coil 4 is wound to be 0.56m in side length size and N in turn numberc128 square coil, which is coaxially fixed between the transmitting coil 2 and the Bucking compensation coil 3, and the distance between the receiving coil 4 and the transmitting coil 2 is hacMeter, the distance between the receiving coil 4 and the Bucking compensation coil 3 is hbcRice, h ═ hac+hbc；
Wherein, the distance h between the Bucking compensation coil 3 and the transmitting coil 2 is obtained by the following method:
the magnetic field strength of the ground coaxial position point, which is jointly aligned with the transmitting coil 2 after the Bucking compensating coil 3 is introduced, is determined according to the condition that the ratio of the magnetic field strength of the ground coaxial position point, which is aligned with the transmitting coil 2, in the vertical direction to the magnetic field strength of the ground coaxial position point is more than 0.9, and the following formula is satisfied:
Ba(h0)-Bb(h0+h)≥0.9Ba(h0)
wherein B isa(h0) Magnetic field strength h in the vertical direction of the point where the ground position of the transmitting coil 2 is located in the direction of the central axis0Is the vertical distance of the transmitting coil 2 from the ground, is a known quantity；Bb(h0+ h) is the magnetic field strength in the vertical direction at the point where the ground position of the Bucking compensation coil 3 along the central axis direction is located;
according to the Bio savart law, the magnetic field intensity B at the position d on the central axis of the square current-carrying coil with the side length of 2rz(d) Satisfies the following conditions:
Figure BDA0002428670150000071
wherein I is the current of the square coil, d is the distance from the center point of the plane of the square coil along the central axis, and μ0Is a vacuum magnetic conductivity; substituting the size distance parameter between the transmitting coil 2 and the Bucking compensation coil 3 into the formula, the distance between the Bucking compensation coil 3 and the transmitting coil 2 can be determined, and the distance h between the Bucking compensation coil 3 and the transmitting coil 2 is obtained to be 0.3m in the embodiment;
the distance h between the receiving coil 4 and the transmitting coil 2acAnd the distance h between the receiving coil 4 and the Bucking compensation coil 3bcThe method for determining the value comprises the following steps:
calculating the side length a and the number of turns N by utilizing a Noemann formulaaThe length of the opposite side of the transmitting coil 2 is c, the number of turns is NcMutual inductance M of the receiving coil 4ac
Figure BDA0002428670150000081
In the formula xa、yaCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil 2; x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil 4; f (x)a,xc) And f (y)a,yc) For the line element integral coefficient, the following equation is satisfied:
Figure BDA0002428670150000082
Figure BDA0002428670150000083
② calculating the side length size b and the number of turns N in the same waybThe mutual inductance M of the Bucking compensation coil 3 to the receiving coil 4bcIs composed of
Figure BDA0002428670150000084
Figure BDA0002428670150000085
Figure BDA0002428670150000086
In the formula xb、ybCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil 2; x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil 4;
utilizing h as hac+hbcUnder known conditions, the proper M can be obtained through the integral formulaac＝MbcThe distance h between the receiving coil 4 and the transmitting coil 2acAnd the distance h between the receiving coil 4 and the Bucking compensation coil 3bcIn this embodiment, h is obtainedac＝0.24m，hbc＝0.06m；
S4, when the mutual inductance coefficients are equal, the current is the same as the current due to the fact that the transmitting coil 2 and the Bucking compensation coil 3 are in a series connection structure, the current is opposite in direction, and at the moment, the total magnetic flux of the surface where the receiving coil 2 is located is zero.
After actually obtaining the theoretical position of the receiving coil 4, because errors caused by factors such as manual winding of the coil are difficult to avoid, the receiving coil 4 is slightly moved and adjusted near the theoretical position value, the state of a secondary eddy current field signal received by the receiving coil 4 is observed through an oscilloscope, the secondary eddy current field signal is adjusted to the optimal position, and finally, the secondary eddy current field signal is fixed.
Referring to fig. 3, a test flow chart of testing the non-coplanar Bucking compensated towed electromagnetic apparatus after the fabrication is completed is shown, which includes the following steps:
s1, after a transmitting coil 2, a packing compensation coil 3, a receiving coil 4 and a transient electromagnetic system host 1 are assembled and fixed on a movable loading platform 5, the input and output ports of the transmitting coil 2, the packing compensation coil 3 and the receiving coil 4 are connected with an interface of the transient electromagnetic system host 1 through leads, and the transmitting coil 2, the packing compensation coil 3 and the receiving coil 4 form a detection coil;
s2, arranging a non-coplanar Bucking compensated dragging type electromagnetic device according to the field condition, selecting a measuring point and a measuring line, setting transient electromagnetic emission parameters and data acquisition parameters through a transient electromagnetic system host 1, and carrying out whole-process data acquisition;
s3, dragging the movable loading platform 5 to sequentially measure the measuring points along the measuring line, and recording the measuring data until the measurement is finished;
and S4, carrying out data preprocessing on the measured data, and then imaging by utilizing a apparent resistivity algorithm.
Modeling simulation is carried out on the non-coplanar Bucking compensated transient electromagnetic device structure in commercial finite element software ANSYS Electronics by utilizing the parameters, the emission current is set to be 10A, the turn-off time is 3 microseconds, the primary field induction voltage of the receiving coil 4 is explored under the condition of uniform half space, the simulation result shows that in the traditional coplanar Bucking compensation design, the primary field induction voltage is 3V, under the design of the non-coplanar Bucking compensation structure, the primary field induction voltage is only 30mV, and primary field coupling interference is more effectively inhibited.

Claims (1)

1. A non-coplanar Bucking compensated towed electromagnetic device, comprising: the transient electromagnetic system comprises a transient electromagnetic system host (1), a transmitting coil (2), a packing compensating coil (3), a receiving coil (4) and a movable loading platform (5), wherein the transient electromagnetic system host (1) is arranged on the movable loading platform (5), the transient electromagnetic system host (1) is respectively connected with the transmitting coil (2) and the receiving coil (4), and the transient electromagnetic system host (1) is used for supplying a pulse current signal to the transmitting coil (2) and simultaneously receiving primary field induced voltage information fed back by the receiving coil (4) to the transmitting coil (2); the transmitting coil (2) is fixed on the table top of the movable loading platform (5), the transmitting coil (2) is positioned below the receiving coil (4) and the packing compensating coil (3), and the transmitting coil (2), the receiving coil (4) and the packing compensating coil (3) are different in center axis and are coplanar; the Bucking compensation coil (3) is connected with the transmitting coil (2) in series, the winding direction of the Bucking compensation coil (3) is opposite to that of the transmitting coil (2), the Bucking compensation coil (3) is positioned above the receiving coil (4), and the Bucking compensation coil (3) is fixed on the movable loading platform (5) through an insulating support; the receiving coil (4) is arranged between the transmitting coil (2) and the Bucking compensation coil (3), and the receiving coil (4) is fixed on the movable loading platform (5) through an insulating support; the movable loading platform (5) is an insulating platform;
clockwise winding the copper enameled wire into a side length a, wherein the number of turns is NaThe method comprises the steps of (1) obtaining a transmitting coil (2) by reserving a certain copper wire allowance, placing the transmitting coil (2) in the center of a movable loading platform (5), wherein the height of the movable loading platform (5) from the ground is h0；
Coaxially and reversely winding the residual copper enameled wire of the transmitting coil (2) at a position h right above the transmitting coil (2) to form a side length b, wherein the number of turns is NbThe Bucking compensation coil (3) is obtained by the square coil;
the receiving coil (4) is wound to have side length c and the number of turns NcThe square coil is coaxially fixed between the transmitting coil (2) and the Bucking compensation coil (3), and the distance between the receiving coil (4) and the transmitting coil (2) is hacThe distance between the receiving coil (4) and the Bucking compensation coil (3) is hbcRice, h ═ hac+hbc；
Wherein, the distance h between the Bucking compensation coil (3) and the transmitting coil (2) is obtained by the following method:
the magnetic field strength of the point which is coaxial with the ground and is provided with the Bucking compensation coil (3) and the transmitting coil (2) together is determined when the ratio of the magnetic field strength of the point in the vertical direction to the magnetic field strength of the point in the vertical direction when only the transmitting coil (2) is larger than 0.9, and the following formula is satisfied:
Ba(h0)-Bb(h0+h)≥0.9Ba(h0)
wherein B isa(h0) A magnetic field strength h in a direction perpendicular to a point where a ground position of the transmitting coil 2 is located in a direction of the central axis0The vertical distance between the transmitting coil (2) and the ground is a known quantity; b isb(h0+ h) is the magnetic field intensity of the Bucking compensation coil (3) in the vertical direction at the point where the ground position is located along the central axis direction;
according to the Bio savart law, the magnetic field intensity B at the position d on the central axis of the square current-carrying coil with the side length of 2rz(d) Satisfies the following conditions:
Figure FDA0003205864270000021
wherein I is the current of the square coil, d is the distance from the central point of the plane of the square coil along the central axis of the square coil, and mu0Is a vacuum magnetic conductivity; substituting the size distance parameters of the transmitting coil (2) and the Bucking compensation coil (3) into the formula to determine the distance h between the Bucking compensation coil (3) and the transmitting coil (2);
wherein the distance h between the receiving coil (4) and the transmitting coil (2)acAnd the distance h between the receiving coil (4) and the Bucking compensation coil (3)bcThe method for determining the value comprises the following steps:
calculating the side length a and the number of turns N by utilizing a Noemann formulaaThe length of the opposite side of the transmitting coil (2) is c, the number of turns is NcMutual inductance M of the receiving coil (4)ac
Figure FDA0003205864270000022
In the formula xa、yaCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil (2); x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil (4); f (x)a,xc) And f (y)a,yc) For the line element integral coefficient, the following equation is satisfied:
Figure FDA0003205864270000031
Figure FDA0003205864270000032
② calculating the side length size b and the number of turns N in the same waybThe mutual inductance coefficient M of the Bucking compensation coil (3) to the receiving coil (4)bcIs composed of
Figure FDA0003205864270000033
Figure FDA0003205864270000034
Figure FDA0003205864270000035
In the formula xb、ybCorresponding to the horizontal and vertical coordinates of the integral point on the transmitting coil (2); x is the number ofc、ycCorresponding to the horizontal and vertical coordinates of the integral point on the receiving coil (4);
utilizing h as hac+hbcUnder known conditions, the proper M can be obtained through the integral formulaac＝MbcWhile the distance h between the receiving coil (4) and the transmitting coil (2)acAnd the distance h between the receiving coil (4) and the Bucking compensation coil (3)bcThe parameters obtained at the moment can enable the receiving coil (4) to be in a primary field zero coupling state;
the transmitting coil (2) is wound by adopting a copper enameled wire to form a multi-turn square loop, and the side length of the transmitting coil (2) is smaller than the width of an urban road;
the Bucking compensation coil (3) is wound by a copper enameled wire to form a single-turn square return wire, and the side length of the Bucking compensation coil (3) is 0.2-0.3 times of that of the transmitting coil (2);
the receiving coil (4) is wound by a copper enameled wire to form a multi-turn square loop, and the side length of the receiving coil (4) is less than or equal to 0.3 time of that of the transmitting coil (2);
and when the transmitting coil (2) is wound, a section is reserved for reversely winding the packing compensation coil (3), and the connecting section of the transmitting coil (2) and the packing compensation coil (3) is wound in a twisted-pair manner.
CN202010228923.8A 2020-03-27 2020-03-27 Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof Active CN111290029B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010228923.8A CN111290029B (en) 2020-03-27 2020-03-27 Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010228923.8A CN111290029B (en) 2020-03-27 2020-03-27 Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof

Publications (2)

Publication Number Publication Date
CN111290029A CN111290029A (en) 2020-06-16
CN111290029B true CN111290029B (en) 2021-11-02

Family

ID=71022107

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010228923.8A Active CN111290029B (en) 2020-03-27 2020-03-27 Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN111290029B (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111965715A (en) * 2020-08-12 2020-11-20 武汉地大华睿地学技术有限公司 Double-emitting-coil transient electromagnetic combination device
CN112099094B (en) * 2020-08-25 2022-04-01 吉林大学 Self-compensation double-emission-structure dragging type transient electromagnetic detection device and method
CN112130214B (en) * 2020-09-24 2023-04-07 中国科学院空天信息创新研究院 Aviation transient electromagnetic eccentric double-compensation coil system
CN114624782A (en) * 2022-01-27 2022-06-14 湖南继善高科技有限公司 Primary field compensation type electromagnetic detection device

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007045963A3 (en) * 2005-10-17 2008-01-03 Anglo Operations Ltd Method and apparatus for conducting electromagnetic exploration
AU2009100027A4 (en) * 2008-01-16 2009-02-19 Ti-Willa Technologies Pty Ltd Electromagnetic Survey for Highly Conductive Ore Bodies
WO2016095043A1 (en) * 2014-12-16 2016-06-23 Geo Equipment Manufacturing Ltd. Electromagnetic survey system bucking enhancement
CN108008451A (en) * 2018-01-30 2018-05-08 安徽惠洲地质安全研究院股份有限公司 A kind of transient electromagnetic detection device and the method for eliminating inductive interferences
CN108776356A (en) * 2018-06-08 2018-11-09 湖南五维地质科技有限公司 The design method of Transient electromagnetic measure device
CN109471180A (en) * 2018-12-28 2019-03-15 国科（重庆）仪器有限公司 A kind of transient electromagnetic apparatus and backoff algorithm
CN109884718A (en) * 2019-01-29 2019-06-14 吉林大学 A kind of magnetic resonance spy water installations and method that dead time is effectively reduced

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007045963A3 (en) * 2005-10-17 2008-01-03 Anglo Operations Ltd Method and apparatus for conducting electromagnetic exploration
AU2009100027A4 (en) * 2008-01-16 2009-02-19 Ti-Willa Technologies Pty Ltd Electromagnetic Survey for Highly Conductive Ore Bodies
WO2016095043A1 (en) * 2014-12-16 2016-06-23 Geo Equipment Manufacturing Ltd. Electromagnetic survey system bucking enhancement
CN108008451A (en) * 2018-01-30 2018-05-08 安徽惠洲地质安全研究院股份有限公司 A kind of transient electromagnetic detection device and the method for eliminating inductive interferences
CN108776356A (en) * 2018-06-08 2018-11-09 湖南五维地质科技有限公司 The design method of Transient electromagnetic measure device
CN109471180A (en) * 2018-12-28 2019-03-15 国科（重庆）仪器有限公司 A kind of transient electromagnetic apparatus and backoff algorithm
CN109884718A (en) * 2019-01-29 2019-06-14 吉林大学 A kind of magnetic resonance spy water installations and method that dead time is effectively reduced

Also Published As

Publication number Publication date
CN111290029A (en) 2020-06-16

Similar Documents

Publication Publication Date Title
CN111290029B (en) Non-coplanar Bucking compensated dragging type electromagnetic device and manufacturing method thereof
CN103487770B (en) A kind of passive detection device for measurement space magnetic field gradient full tensor information
Nabighian et al. Time domain electromagnetic prospecting methods
CN102565862B (en) Gradient measurement method of transient electromagnetic response signal and observation device thereof
CN109209363B (en) Through-casing formation differential resistivity logging probe structure
CN102062876A (en) Electrical sounding method for whole-region couple source frequency domain
Chen et al. Weak coupling technology with noncoplanar bucking coil in a small-loop transient electromagnetic system
US20170023694A1 (en) Apparatus for airborne and ground electromagnetic prospecting and method thereof
CN109358367A (en) A kind of horizontal moving shallow transient electromagnetic fine granularing scalability method
CN105548923A (en) Two-dimensional high-frequency rotation magnetic property sensing device
CN102183341B (en) Nuclear magnetic resonance detection meter and detection method of hidden troubles of dam leakage
CA2110433C (en) Magnetic cartography process and apparatus
Lin et al. Rapid and high-resolution detection of urban underground space using transient electromagnetic method
CN102854536B (en) Five bar type length of side adjustable type sea cable exploring antenna battle array and detection methods thereof
CN108761540B (en) A kind of frequency domain natural electric field three-dimensional exploitation method
CN114460505A (en) Low-noise induction type magnetometer for weak alternating magnetic field magnitude transmission
Sørensen et al. TDEM in groundwater mapping—a continuous approach
Lodha et al. Practical airborne EM (AEM) interpretation using a sphere model
CN110208864A (en) A kind of underground metalliferous detection system and its detection method
WANG et al. A Bird Calibration Device of Helicopter‐Borne TEM with a Concentric Bucking Loop
US4199720A (en) Method for investigating the conductivity of layered terrain
Liu et al. Turn-off current and TEM field based on distributed capacitance model of multiple coils in helicopter transient electromagnetic system
CN201796131U (en) Two-dimensional low-radio frequency field vector measuring tool
Zhou et al. A calibration method of ground-airborne frequency domain electromagnetic receving system based on magnetic source excitation
CN113534266B (en) Multi-receiving coil spread spectrum aviation electromagnetic exploration device containing compensation ring Z component

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
GR01 Patent grant
GR01 Patent grant