CN203607538U - Magnetic dipole antenna - Google Patents

Magnetic dipole antenna Download PDF

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Publication number
CN203607538U
CN203607538U CN201320822046.2U CN201320822046U CN203607538U CN 203607538 U CN203607538 U CN 203607538U CN 201320822046 U CN201320822046 U CN 201320822046U CN 203607538 U CN203607538 U CN 203607538U
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CN
China
Prior art keywords
magnetic
antenna
measuring instrument
dipole antenna
resistivity measuring
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Expired - Fee Related
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CN201320822046.2U
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Chinese (zh)
Inventor
刘策
李敬
吴素明
王华平
梁任岳
任威
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Bitswave Suzhou Co Ltd
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Bitswave Suzhou Co Ltd
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Abstract

The utility model relates to the technical field of geological prospecting, and especially relates to a magnetic dipole antenna. The antenna is arranged on a resistivity measurement instrument with a longitudinal shaft and an outer surface. The antenna comprises: a notch formed on the outer surface of the resistivity measurement instrument; and a coaxial line connecting piece which is arranged under the outer surface of the resistivity measurement instrument. A power line enables the end wall of the notch to be electrically connected with the central conductor of a coaxial connector located at the other end of the notch. The notch and the power line form a magnetic dipole, and transmits or receives an electromagnetic signal. Compared with the prior art, the antenna provided by the utility model is more economical, is easier to produce, and improves the technological level.

Description

A kind of magnetic-dipole antenna
Technical field
The utility model relates to geological exploration techniques field, in particular to a kind of magnetic-dipole antenna device.
Background technology
In petroleum industry field, the method for well-known use electric measurement method collection down-hole information has multiple, as well logging during (" LWD "), and measurement while drilling (" MWD ").This type of technology is used for obtaining formation resistivity (or conductivity already; Term " resistivity " and " conductivity ", but can be general in the utility model) and various petrophysical model (as Archie law), to help the petrophysical property of determining stratum and corresponding fluids.In the prior art, resistivity is to determine the important parameter of oil gas (as crude oil or natural gas) and water content in porous stratum.Allow well bore keep oil-producing formation (hydrocarbon bearing formation) inner, to improve as far as possible to greatest extent recovery ratio as far as possible.
Along with the development of modern drilling technology and logging technique, horizontal drilling, be drilling well and geological stratification at least at angle, more and more general, because it can improve the length of exposure of oil-producing formation (hydrocarbon bearing formation), inner farthest well bore is remained on to oil-producing formation (hydrocarbon bearing formation), improve as far as possible to greatest extent recovery ratio.Therefore it is necessary that the directed resistivity measuring instrument that, possesses azimuthal sensitivity is that rear follow-up hole turns to.Turn to the decision can be according to stratum Boundary Recognition measurement result, angle, stratum be detected and fracture characteristics is made.
Directed resistivity measurement generally includes transmitting and/or receives laterally (x-type or y-type) or mixed type (such as mixing x-and z-type) electromagnetic wave.Carry out this type of measure in can adopt various types of antenna configurations, such as horizontal line antenna configuration (x-type) as shown in Figure 1A, dual planar antennas configuration as shown in Figure 1B, saddle type antenna configuration (x-type and z-type as shown in Figure 1 C, mixed type), and inclined antenna as shown in Fig. 1 D.The indicated direction of the magnetic moment of the horizontal antenna in Figure 1A, perpendicular to the longitudinal axis of directed resistivity measuring instrument, is furnished with Longitudinal Antenna on it.Dual planar antennas, saddle type antenna and inclined antenna configure as shown in Figure 1B, 1C and 1D, can launch or receive the cross stream component in magnetic field, carry out azimuthal resistivity measurement.
As mentioned above, although directed resistivity measuring instrument by commercial use, the precision of these measuring instruments is not high, operating distance is short, still needs the antenna configuration of resistivity measuring instrument to improve.
Summary of the invention
The purpose of this utility model is to provide a kind of magnetic-dipole antenna device, not high to solve the precision of current measuring instrument, the problem that operating distance is short.
In embodiment of the present utility model, provide magnetic-dipole antenna, be configured in the resistivity measuring instrument with longitudinal axis and outer surface, it comprises: the recess forming on described resistivity measuring instrument outer surface; Coaxial connector, is configured in described resistivity measuring instrument outer surface below; Electric wire is electrically connected described recess end wall with the center conductor of the coaxial connector that is positioned at the described recess other end, described recess and described electric wire form magnetic dipole, transmitting or receiving electromagnetic signals.
Also comprise the permeability magnetic material being filled in described recess.
Described permeability magnetic material is magnetic material.
Described magnetic material is the one in Ferrite Material, nonconducting magnetic alloy, iron powder and dilval.
In described recess, be filled with protective materials.
Described protective materials is epoxy resin.
Described recess is circular.
Described recess is rectangle.
Be formed with many grooves across described recess on described resistivity measuring instrument surface.
Described groove is oval.
Owing to adopting magnetic dipole as transmitting and receiving antenna, compared to existing technology, precision is higher for the utility model, and operating distance is longer, has improved technical level.
Accompanying drawing explanation
Figure 1A is depicted as the prior art of transverse annular antenna in conventional resistivity measuring instrument;
Figure 1B, 1C, 1D are depicted as and can radiate or receive magnetic field cross stream component, carry out the prior art of the antenna embodiment of azimuthal resistivity measurement;
Figure 2 shows that the directed resistivity measuring instrument front elevation of being furnished with a conventional well logging during system;
Fig. 3 A is depicted as in one of them embodiment of the present invention, the perspective view of the directed resistivity measuring instrument with slot antenna as shown in Figure 2;
Fig. 3 B is depicted as along the profile of the slot antenna as shown in Figure 3A of AA ';
Fig. 3 C is depicted as along the profile of the slot antenna as shown in Figure 3A of BB ';
Fig. 4 A is depicted as in other embodiments of the invention, is furnished with the directed resistivity measuring instrument of slot antenna and many transverse slots;
Fig. 4 B is depicted as the slot antenna profile along CC ';
Fig. 5 A is depicted as the perspective view of the directed resistivity measuring instrument with a pair of transmitter antenna and receiver antenna in one of them embodiment of the present invention;
Fig. 5 B is depicted as in other embodiments of the invention, is with a pair of transmitter antenna and receiver antenna, is furnished with the perspective view of the directed resistivity measuring instrument of many transverse slots;
Fig. 6 A is depicted as the transmitting Vector Magnetic Field that transmitter antenna as shown in Figure 5 B generates;
Fig. 6 B is depicted as the radia magnetic field intensity that transmitter antenna as shown in Figure 5 B forms on aximuthpiston;
Figure 7 shows that in one of them embodiment of the present invention, in simulation model, operate the schematic diagram of the directed resistivity measuring instrument in Fig. 5 B, for showing the azimuthal sensitivity of directed resistivity measuring instrument;
Fig. 8 A is depicted as receiver antenna induced potential imaginary data figure and contrasts the simulation result of the model of the directed resistivity measuring instrument anglec of rotation in Fig. 7;
Fig. 8 B is depicted as the real part of induced potential on receiver antenna and contrasts the simulation result of directed resistivity measuring instrument anglec of rotation model;
Figure 9 shows that receiver antenna induced potential amplitude data figure contrasts the simulation result of the model of resistivity interface distance in Fig. 7;
Embodiment
Also by reference to the accompanying drawings the utility model is described in further detail below by specific embodiment.
Figure 2 shows that the front elevation of being furnished with a directed resistivity measuring instrument 212 of conventional well logging during system 200 in one of them embodiment of the present utility model.Conventional well logging during system 200 comprises rig 202, drill string 206, drill bit 210 and directed resistivity measuring instrument 212.Drill string 206, under the support of rig 202, can extend into well 208 from surface 204.Drill string 206 can be brought drill bit 210 and directed resistivity measuring instrument 212, carries out the geological characteristics on stratum and measure in drilling process.
In an embodiment, drill string 206 also comprises mud-pressure-pulse telemetry system, drilling motor, measuring transducer therein, such as nuclear logging instrument and azimuth sensor, such as accelerometer, gyroscope or magnetometer, accelerates the measurement on stratum around.Certainly, drill string 206 can be combined with hoisting equipment, for lifting or put down drill string 206.
In the utility model, directed resistivity measuring instrument 212 not only can be used in well logging during system " (LWD ", Logging While Drilling) in, also can be applied in measurement-while-drilling system (" MWD ", Measure While Drilling) and well testing application.Certainly, directed resistivity measuring instrument 212 also can use under any drilling environment, on the bank or coastal waters, also can use together with various drilling platforms, includes but not limited to fix, floating and semi-submerged platform.
Fig. 3 A is depicted as in one of them embodiment of the present utility model the perspective view of directed resistivity measuring instrument 212 as shown in Figure 2.Directed resistivity measuring instrument 212 can comprise configuration slot antenna 302 thereon.
Fig. 3 B is depicted as along the profile of the slot antenna as shown in Figure 3A 302 of AA '.Slot antenna 302 can comprise the recess 304 forming on directed resistivity measuring instrument 212 outer surfaces, is with an electric wire 306 to be placed in the inside.Can be by the headwall of recess 304 308 after electric wire 306 energisings, the center conductor of the coaxial connector 310 of recess 304 other ends.Coaxial connector 310 can couple together the electric wire of 304 li of recesses 306 and circuit chamber 312, can be placed in below recess 304 outsides and directed resistivity measuring instrument 212 outer surfaces 300.Transmitter and receiver circuit can be mixed in circuit chamber 312, for the treatment of electromagnetic signal to be launched or that receive.
In an embodiment, slot antenna 302 not only can be parallel to measuring instrument axis therein, also can be along other direction, and such as perpendicular to measuring instrument axis or be positioned at any angle of measuring instrument axis.
In an embodiment, permeability magnetic material 314 can be filled in 304 li of recesses therein, strengthens slot antenna 302 and transmits and receives ability.Permeability magnetic material 314 can be magnetic material, can be placed between center line and notched bottoms.Magnetic material can be, but not limited to Ferrite Material, nonconducting magnetic alloy, iron powder and dilval.
In an embodiment, protective materials 316 can be filled in 304 li of recesses therein.Protective materials 316 can, for the protection of slot antenna 302, prevent in drilling process damaged.Protective materials can be, but not limited to epoxy resin, can be placed on above permeability magnetic material.
Fig. 3 C is depicted as along the profile of the slot antenna as shown in Figure 3A 302 of BB '.The shape of recess 304 can be varied, such as circle, rectangle or any other shape.
Fig. 4 A is depicted as the directed resistivity measuring instrument of being furnished with a slot antenna 302 and many transverse slots 402 in other embodiment of the present utility model.Many transverse slot 402 can, on the outer surface of directed resistivity measuring instrument 212 300, across recess 304, increase the depression/magnetic region thoroughly of directed resistivity measuring instrument 212.Like that, can strengthen the efficiency that transmits and receives of slot antenna 302.
Fig. 4 B is depicted as along the profile of the slot antenna 302 of CC '.The shape of recess 402 can be varied, such as circle, rectangle, ellipse or any other shape.
Fig. 5 A is depicted as in one of them embodiment of the present utility model, the perspective view of the directed resistivity measuring instrument 212 with a pair of transmitter antenna 500 and receiver antenna 502.Transmitter antenna 500 and receiver antenna 502 can be placed on directed resistivity measuring instrument 212, are configured to slot antenna 302, as shown in Fig. 3 A, 3B and 3C.The direction of transmitter antenna 500 and receiver antenna 502 can be parallel to the longitudinal axis of directed resistivity measuring instrument 212 substantially, each other one, interval axial distance.According to principle of reciprocity, every strip antenna, as long as couple together with suitable transmitter or receiver circuit, can be used as transmitter antenna or receiver antenna.
Fig. 5 B is depicted as in one of them embodiment of the present utility model, and the perspective view of the directed resistivity measuring instrument 212 with a pair of transmitter antenna 500 and receiver antenna 502, can mix many transverse slots 402.Transverse slot 402 strengthens the ability that transmits and receives of transmitter antenna 500 and receiver antenna 502, as shown in Fig. 4 A and 4B.
At any time, all the utility model must not be limited in any special geometric figure, the quantity in this type of slot antenna and gap also must not limit to some extent.
In an embodiment, transmitter antenna 500 or receiver antenna 502 can be replaced with the antenna of other any type/shape therein.
Fig. 6 A is depicted as the transmitting Vector Magnetic Field that transmitter antenna 500 as shown in Figure 5 B produces.Many arrows 600 can be indicated the polarity in magnetic field.Region 602, dotted line is irised out the area coming, indication transmitter antenna 500 polarity of the magnetic field above, its axle is in the x-direction.Many arrows 600 that region is 602 li can indicate transmitter antenna 500 magnetic field above almost along azimuth direction polarization, and simulation y-is to the magnetic field of magnetic dipole.According to principle of reciprocity, corresponding receiver antenna 502 is more responsive to appearing at the bed boundary of angle 604 the insides in 602 li, region.
Fig. 6 B is depicted as the radia magnetic field intensity that transmitter antenna 500 as shown in Figure 5 B generates under aximuthpiston.The energy that can indicate most of electromagnetic signal is launched along the dead ahead of 604 li of angles from transmitter antenna 500 (positive x to).In view of the magnetic field polarization type in Fig. 6 A and 6B and radiant energy type, can draw to draw a conclusion: the slot antenna configuration in one of them embodiment of the present utility model is applicable to directed resistivity measurement.
In operating process, transmitter antenna 500 and the receiver antenna 502 of being furnished with slot antenna can be used as magnetic dipole, transmitting/receiving electromagnetic signal.Therefore, slot antenna 302 also can be described as gap magnetic-dipole antenna.In drilling process, in the time that directed resistivity measuring instrument approaches resistivity interface, the induced potential on receiver antenna 502 can reflect whether there is this interface (by the variation of amplitude fading and phase shift), as prior art.In addition, the sinusoidal variations of receiver antenna 502 induced potentials in the time that directed resistivity measuring instrument 212 rotates can be indicated the direction at resistivity interface, because almost polarize along azimuth direction in the magnetic field before the antenna with gap antenna configuration.
Figure 7 shows that in one of them embodiment of the present utility model, the directed resistivity measuring instrument 212 of operation in simulation model 700, as shown in Figure 5 B, for showing the azimuthal sensitivity of directed resistivity measuring instrument 212, Fig. 8 A, 8B and 9 are depicted as the simulation result of model 700 in Fig. 7.In Fig. 7, model 700 can comprise a 3D cube, is divided into two parts by vertical resistivity interface 706.The resistivity of left-hand component 702 is 10 ohm-meter, and the resistivity on the right 704 is 1 ohm-meter.Directed resistivity measuring instrument 212 can be included in left-hand component 702 the insides, and towards the positive x direction rotation at resistivity interface 706.
Fig. 8 A is depicted as, and receiver antenna 502 induced potential imaginary data figure contrast the simulation result of the model 700 of directed resistivity measuring instrument 212 anglecs of rotation in Fig. 7.Fig. 8 B is depicted as, and on receiver antenna 502, the real part of induced potential contrasts the simulation result of directed resistivity measuring instrument 212 anglecs of rotation model 700 in Fig. 7.Fig. 8 A and 8B are depicted as when directed resistivity measuring instrument 212 is during near resistivity interface (5 feet) 706, and the imaginary part of the induced potential on receiver antenna 502 and real part start the anglec of rotation generation sinusoidal variations along directed resistivity measuring instrument 212.Like that, can identify resistivity interface 706 whether along direction (positive x direction) above, appear on the path of directed resistivity measuring instrument 212.
Figure 9 shows that in Fig. 7, receiver antenna 502 induced potential amplitude data figure contrast the simulation result of the model 700 of resistivity interface 706 distances.According to Fig. 9, directed resistivity measuring instrument 212 is the closer to resistivity interface 706, reacts induced potential amplitude on receiver antenna 502 larger.In fact, the distance between receiver antenna 502 and resistivity interface 706 can be derived, as function (" ceiling voltage ", " V of the induced potential amplitude recording on receiver antenna 502 max"), is adjacent to layer resistivity (" R 1, R 2"), dielectric constant (" ε 1, ε 2"), and permeability (" μ 1, μ 2") is as follows.
d=f(V max,R 1,R 21212)(1)
In low frequency and nonmagnetic stratum, around the resistivity on stratum is played the part of leading position in decision frontier distance.Equation (1) can be reduced to equation (2).
d=f(V max,R 1,R 2)(2)
Can be in advance for ceiling voltage be adjacent to layer resistivity, set up a three-dimensional and check table by carry out forward modeling 212 li of directed resistivity measuring instruments, improve the efficiency of orientation survey.Forward model can be transducer and provide a whole set of mathematical relationship under varying environment and different electrical property.The input data that the ceiling voltage that receiver antenna 502 records can be used as three-dimensional checks table, directed resistivity measuring instrument 212 can be by surrounding known or that derive bottom resistivity generation to the distance between resistivity interface 706, can be based upon in advance in form or record from the equipment that other and directed resistivity measuring instrument 212 are coupled.
As implied above, the sinusoidal variations induced potential on receiver antenna 502 can be used as the designation data of stratum electrical characteristics around, includes but not limited to apart from the distance at resistivity interface 706 and the direction at resistivity interface 706.Therefore, there is azimuthal sensitivity with the directed resistivity measuring instrument 212 of gap antenna configuration, can make direction for follow-up drilling well.
In an embodiment, described second slot antenna of described first slot antenna of internally charged line and internally charged line is placed on to the recess on resistivity measuring instrument outer surface therein.
In an embodiment, will after described electric wire energising, be connected with the headwall of recess therein, the center conductor of coaxial connector is positioned at the other end of recess, produces magnetic field as magnetic dipole.
In an embodiment, coaxial connector can couple together the electric wire of recess and a certain circuit therein, for transmitting, can be placed in recess outside and resistivity measuring instrument outer surface below.
At any time, all the utility model must not be limited in any specific step order or require any specific step in Figure 10.
Obviously, those skilled in the art should be understood that, above-mentioned each module of the present utility model or each step can realize with general calculation element, they can concentrate on single calculation element, or be distributed on the network that multiple calculation elements form, alternatively, they can be realized with the executable program code of calculation element, thereby, they can be stored in storage device and be carried out by calculation element, or they are made into respectively to each integrated circuit modules, or the multiple modules in them or step are made into single integrated circuit module to be realized.Like this, the utility model is not restricted to any specific hardware and software combination.
The foregoing is only preferred embodiment of the present utility model, be not limited to the utility model, for a person skilled in the art, the utility model can have various modifications and variations.All within spirit of the present utility model and principle, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection range of the present utility model.

Claims (10)

1. a magnetic-dipole antenna, is configured on the resistivity measuring instrument with longitudinal axis and outer surface, it is characterized in that, comprising:
The recess forming on described resistivity measuring instrument outer surface;
Coaxial connector, is configured in described resistivity measuring instrument outer surface below;
Electric wire is electrically connected described recess end wall with the center conductor of the coaxial connector that is positioned at the described recess other end, described recess and described electric wire form magnetic dipole, transmitting or receiving electromagnetic signals.
2. magnetic-dipole antenna according to claim 1, is characterized in that, also comprises the permeability magnetic material being filled in described recess.
3. magnetic-dipole antenna according to claim 2, is characterized in that, described permeability magnetic material is magnetic material.
4. magnetic-dipole antenna according to claim 3, is characterized in that, described magnetic material is the one in Ferrite Material, nonconducting magnetic alloy, iron powder and dilval.
5. magnetic-dipole antenna according to claim 1, is characterized in that, in described recess, is filled with protective materials.
6. magnetic-dipole antenna according to claim 5, is characterized in that, described protective materials is epoxy resin.
7. magnetic-dipole antenna according to claim 1, is characterized in that, described recess is circular.
8. magnetic-dipole antenna according to claim 1, is characterized in that, described recess is rectangle.
9. magnetic-dipole antenna according to claim 1, is characterized in that, is formed with many grooves across described recess on described resistivity measuring instrument surface.
10. magnetic-dipole antenna according to claim 9, is characterized in that, described groove is oval.
CN201320822046.2U 2013-12-12 2013-12-12 Magnetic dipole antenna Expired - Fee Related CN203607538U (en)

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Application Number Priority Date Filing Date Title
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105715255A (en) * 2016-01-26 2016-06-29 中国石油集团长城钻探工程有限公司 Device for detecting formation boundary and measuring formation resistivity
CN109802718A (en) * 2017-11-14 2019-05-24 中国石油化工股份有限公司 Electromagnetic measurement while drilling repeater and electromagnetic measurement while drilling system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105715255A (en) * 2016-01-26 2016-06-29 中国石油集团长城钻探工程有限公司 Device for detecting formation boundary and measuring formation resistivity
CN109802718A (en) * 2017-11-14 2019-05-24 中国石油化工股份有限公司 Electromagnetic measurement while drilling repeater and electromagnetic measurement while drilling system
CN109802718B (en) * 2017-11-14 2021-03-23 中国石油化工股份有限公司 Electromagnetic measurement-while-drilling repeater and electromagnetic measurement-while-drilling system

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C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20140521

Termination date: 20201212

CF01 Termination of patent right due to non-payment of annual fee