Magnetic signal acquisition device, magnetic positioning system and magnetic positioning method

Abstract

The invention discloses a magnetic signal acquisition device and a magnetic positioning system and method, and relates to the technical field of drilling, and the magnetic signal acquisition device comprises a measurement unit and a logging connection unit; the measuring unit is arranged in the butt joint vertical well and is used for measuring magnetic field intensities generated by magnetic signals at a target spot and a first position of the butt joint vertical well and corresponding included angles; wherein the included angle is the included angle of a space rectangular coordinate system where the measuring unit is located relative to the x axis, the y axis and the z axis of a magnetic north coordinate system when the measuring unit is located at the target point or the first position; the distance between the first position and the target spot is a preset distance; and the well logging connecting unit is connected with the measuring unit and used for adjusting the position of the measuring unit in the butt joint vertical well. According to the method, the magnetic field intensity in the butt joint vertical well can be accurately collected in a complex environment, then the azimuth angle of the magnetic rotating connector is accurately calculated, and the butt joint precision of the drill bit and the butt joint vertical well is improved.

Description

Technical Field

[0001] The present application relates to the field of drilling technology, and in particular to a magnetic signal acquisition device, a magnetic positioning system and a method. Background Art

[0002] The existing method of rotating magnetic measurement for docking vertical wells requires the use of a fluxgate sensor to measure the drill bit orientation in advance as a known quantity. When encountering complex terrain conditions such as magnetically abnormal formations, the static magnetic field will be greatly affected. The fluxgate sensor measures its own orientation by measuring the orientation of the magnetic flux lines of the earth's magnetic field. When encountering magnetically abnormal formations, the orientation data measured by the fluxgate sensor is inaccurate, resulting in reduced target accuracy in the docking vertical well. Summary of the invention

[0003] The purpose of this application is to provide a magnetic signal acquisition device, a magnetic positioning system and a method, which can accurately collect the magnetic field strength in a docking vertical well in a complex environment, and then accurately calculate the azimuth angle of the magnetic rotary joint, thereby improving the docking accuracy between the drill bit and the docking vertical well.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] In a first aspect, the present application provides a magnetic signal acquisition device, the magnetic signal acquisition device comprising: a measurement unit and a logging connection unit;

[0006] The measuring unit is arranged in the docking vertical well, and is used to measure the magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well respectively; wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located and the magnetic north coordinate system when the measuring unit is located at the target point or the first position; the magnetic north coordinate system takes the center of gravity of the magnetic source generating the magnetic signal as the origin, the x-axis is the geomagnetic north pole, the y-axis is the direction of gravity, and the z-axis is perpendicular to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance;

[0007] The logging connection unit is connected to the measuring unit and is used to adjust the position of the measuring unit in the docking vertical well.

[0008] Further, the measuring unit comprises a measuring nipple, a lower magnetometer and an upper magnetometer;

[0009] The lower magnetometer is arranged in the measuring sub, located at the target point, and is used to collect the magnetic field intensity generated by the magnetic signal at the target point of the vertical well;

[0010] The upper magnetometer is arranged in the measuring sub, located at the first position, and the distance between the upper magnetometer and the lower magnetometer is the preset distance, and is used to collect the magnetic field intensity generated by the magnetic signal at the first position of the docking vertical well;

[0011] The measuring short section is connected to the logging connection unit and is used to measure the angles of the spatial rectangular coordinate system where the upper magnetometer is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and the angles of the spatial rectangular coordinate system where the lower magnetometer is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and send the magnetic field strength and angle to the logging connection unit.

[0012] Further, the measuring unit comprises: a measuring nipple and a magnetometer;

[0013] The magnetometer is arranged in the measuring sub, and is used to collect the magnetic field strength generated by the magnetic signal at the target point and the first position of the docking vertical well respectively;

[0014] The measuring nipple is connected to the logging connection unit and is used to measure the angles of the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the magnetometer is located relative to the magnetic north coordinate system, and send the angles and the magnetic field strength to the logging connection unit.

[0015] Furthermore, the logging connection unit includes an armored cable, a wellhead pulley and a logging winch; the wellhead pulley is arranged at the wellhead of the docking vertical well, the logging winch is arranged on the ground, the armored cable is wound around the body of the logging winch, one end of the armored cable passes through the wellhead pulley and is connected to the measuring unit, and the other end of the armored cable is connected to the computing unit; the logging winch is used to adjust the length of the armored cable, thereby adjusting the position of the measuring unit in the docking vertical well.

[0016] In a second aspect, the present application provides a magnetic positioning system, the magnetic positioning system comprising: the magnetic signal acquisition device, the magnetic signal generating unit and the computing unit mentioned above;

[0017] A magnetic signal generating unit, used to generate a magnetic signal, wherein the magnetic signal acts on the docking vertical well;

[0018] A magnetic signal acquisition device, used for acquiring the magnetic field strength and corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well respectively; wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located and the magnetic north coordinate system when the measuring unit in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotary joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the gravity direction, and the z-axis is parallel to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance;

[0019] A calculation unit is connected to the magnetic signal acquisition device and is used to calculate the azimuth angle of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle.

[0020] In a third aspect, the present application provides a magnetic positioning method, the magnetic positioning method comprising:

[0021] Acquiring a magnetic signal, wherein the magnetic signal acts on the docking vertical well;

[0022] The magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well are collected; wherein the distance between the first position and the target point is a preset distance; the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located relative to the magnetic north coordinate system when the measuring unit in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotary joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the gravity direction, and the z-axis is perpendicular to the x-axis and the y-axis;

[0023] The azimuth angle of the magnetic rotary joint is calculated according to the preset distance, the magnetic field strength and the angle.

[0024] Further, calculating the azimuth of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle includes:

[0025] Get the azimuth and top angle of the drill bit;

[0026] Determine a conversion matrix according to the azimuth angle, the vertex angle and the included angle;

[0027] Calculate the position coordinates of the measuring unit in the magnetic north coordinate system when the measuring unit is at the target point and the first position respectively according to the magnetic field strength and the conversion matrix;

[0028] The azimuth of the magnetic rotary joint is calculated according to the preset distance and the position coordinates in the magnetic north coordinate system.

[0029] Further, calculating the position coordinates of the measuring unit in the magnetic north coordinate system when the measuring unit is at the target point and the first position respectively according to the magnetic field strength and the conversion matrix includes:

[0030] Using the conversion matrix to convert the magnetic field intensity to obtain a converted magnetic field intensity;

[0031] The position coordinates of the measuring unit in the magnetic space rectangular coordinate system are calculated according to the converted magnetic field intensity and the mathematical model of the magnetic field intensity distribution when the measuring unit is at the target point and the first position; the magnetic space rectangular coordinate system takes the center of gravity of the magnetic rotary joint as the origin, the straight line where the axis of rotation of the magnetic rotary joint is located is the x-axis, the y-axis is perpendicular to the x-axis and in the horizontal plane, and the z-axis is perpendicular to both the y-axis and the x-axis;

[0032] The conversion matrix is ​​used to convert the position coordinates of the magnetic space rectangular coordinate system into the position coordinates in the magnetic north coordinate system.

[0033] Further, the conversion matrix includes a first conversion matrix and a second conversion matrix;

[0034] The expression of the first conversion matrix is:

[0035]

[0036] Where A is the first transformation matrix, a, b, and c are the angles of the x-axis, y-axis, and z-axis of the spatial rectangular coordinate system of the measurement unit relative to the magnetic north coordinate system when the measurement unit is at the target point, and α 0 is the top angle of the drill bit, is the azimuth angle of the magnetic rotary joint;

[0037] The expression of the second conversion matrix is:

[0038]

[0039] Wherein, B is the second transformation matrix, d, e, and f are respectively the angles of the x-axis, y-axis, and z-axis of the spatial rectangular coordinate system where the measuring unit is located relative to the magnetic north coordinate system when the measuring unit is in the first position.

[0040] Furthermore, the expression of the mathematical model of magnetic field intensity distribution is:

[0041]

[0042] Wherein, F(x, y, z) is the mathematical model of magnetic field intensity distribution, (x, y, z) is a point in the rectangular coordinate system of the magnetic space, μ is the magnetic permeability, M is the magnetic moment value, and B' x , B' y , B' zThey are the components of the magnetic field intensity at the position (x, y, z) along the three axes in the rectangular coordinate system of the magnetic space.

[0043] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0044] The present application provides a magnetic signal acquisition device, a magnetic positioning system and a method. The magnetic signal acquisition device can collect the magnetic field strength and corresponding angle generated by the magnetic signal at different positions in the docking vertical well. When encountering a magnetically abnormal formation, it has no effect on the magnetic field strength collected by the measuring unit. On this basis, according to the magnetic field strength at different positions collected, the angles of the measuring unit relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system at different positions, and the preset distances between different positions, the azimuth angle of the magnetic rotary joint is accurately calculated, thereby improving the target accuracy of the docking vertical well. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1 This is a structural schematic diagram of a magnetic positioning system in one embodiment of the present application;

[0047] Figure 2 A schematic diagram of the structure of a measurement unit provided in another embodiment of the present application;

[0048] Figure 3 is a schematic diagram of the positional relationship between the target point, the first position and the magnetic rotary joint;

[0049] Figure 4 A diagram of an application environment of a magnetic positioning method provided by another embodiment of the present application;

[0050] Figure 5 A flow chart of a magnetic positioning method provided in one embodiment of the present application. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0052] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0053] In an exemplary embodiment, Figure 1 As shown, the present application provides a magnetic signal acquisition device, which includes a measurement unit 1 and a logging connection unit 2.

[0054] The measuring unit 1 is arranged in the docking vertical well 3, and is used to measure the magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well 3 respectively; wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit 1 is located and the magnetic north coordinate system when the measuring unit 1 is located at the target point or the first position; the magnetic north coordinate system takes the center of gravity of the magnetic source generating the magnetic signal as the origin, the x-axis is the geomagnetic north pole, the y-axis is the direction of gravity, and the z-axis is perpendicular to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance;

[0055] The logging connection unit 2 is connected to the measuring unit 1 and is used to adjust the position of the measuring unit 1 in the docking vertical well 3.

[0056] The magnetic signal acquisition device in the present application can acquire magnetic field strengths at different positions.

[0057] like Figure 1 As shown, the measuring unit 1 includes a measuring short section 4 , an upper magnetometer 5 and a lower magnetometer 6 .

[0058] The lower magnetometer 6 is arranged in the measuring sub 4 and located at the target point, and is used to collect the magnetic field intensity generated by the magnetic signal at the target point of the docking vertical well 3 .

[0059] The upper magnetometer 5 is arranged in the measuring short section 4 and is located at the first position, and the distance between the upper magnetometer 5 and the lower magnetometer 6 is the preset distance, and is used to collect the magnetic field strength generated by the magnetic signal at the first position of the docking vertical well.

[0060] The measuring short section 4 is connected to the logging connection unit 2, and is used to measure the angles of the spatial rectangular coordinate system where the upper magnetometer 5 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and the angles of the spatial rectangular coordinate system where the lower magnetometer 6 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and send the magnetic field strength and angle to the logging connection unit 2.

[0061] like Figure 1As shown, the logging connection unit 2 includes an armored cable 7, a wellhead pulley 8 and a logging winch 9. The wellhead pulley 8 is arranged at the wellhead of the docking vertical well 3, the logging winch 9 is arranged on the ground, the armored cable 7 is wound on the body of the logging winch 9, one end of the armored cable 7 passes through the wellhead pulley 8 and is connected to the measurement unit 1, and the other end of the armored cable 7 is connected to the calculation unit 10; the logging winch 9 is used to adjust the length of the armored cable 7, thereby adjusting the position of the measurement unit 1 in the docking vertical well 3.

[0062] In another exemplary embodiment of the present application, Figure 2 As shown, the measuring unit 1 includes a measuring sub 4 and a magnetometer 11 .

[0063] The magnetometer 11 is disposed in the measuring sub 4 and is used to collect the magnetic field strength generated by the magnetic signal at the target point and the first position of the docking vertical well 3. The measuring sub 4 is connected to the well logging connection unit 2.

[0064] The measuring sub 4 measures the angles of the spatial rectangular coordinate system where the magnetometer 11 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and sends the angles and the magnetic field strength to the logging connection unit 2 .

[0065] In actual use, the measuring sub 4 and the magnetometer 11 are first placed at the target point using the logging connection unit 2, and the magnetic field strength generated by the magnetic signal at the target point of the docking vertical well 3 and the angles of the spatial rectangular coordinate system where the magnetometer 11 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are measured. After the measurement is completed, the placement positions of the measuring sub 4 and the magnetometer 11 are changed using the logging connection unit 2, and the measuring sub 4 and the magnetometer 11 are placed at the first position, and the magnetic field strength generated by the magnetic signal at the first position of the docking vertical well 3 and the angles of the spatial rectangular coordinate system where the magnetometer 11 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are measured, thereby completing the measurement.

[0066] like Figure 3 As shown, O1 is the target point, O2 is the first position, O is the magnetic rotary joint 14, and L is the distance between the target point and the first position, which can be obtained by field measurement. Two magnetometers (i.e., the upper magnetometer 5 and the lower magnetometer 6) or one magnetometer (i.e., the magnetometer 11) are respectively arranged in the measuring short section 4 to measure at the target point and the first position.

[0067] The upper magnetometer 5 and the lower magnetometer 6 provided in the measuring sub 4 are used to perform measurement at the target point and the first position of the vertical well 3. The actual operation includes:

[0068] First, the measuring sub 4 is lowered into the docking vertical well 3 by the logging winch 9, the upper magnetometer 5 is located at the first position, the lower magnetometer 6 is located at the target point, and the upper magnetometer 5 and the lower magnetometer 6 in the measuring sub 4 are started. The magnetic signal generating unit is inserted into the directional well, and the magnetic rotary joint 14 is maintained to rotate at a certain speed to generate a magnetic signal to act on the docking vertical well. The upper magnetometer 5 and the lower magnetometer 6 in the working state measure the magnetic field strength of the first position and the target point in the docking vertical well 3 in real time, and the angle of the spatial rectangular coordinate system where the upper magnetometer 5 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and the angle of the spatial rectangular coordinate system where the lower magnetometer 6 is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system. The collected magnetic field strength and angle are uploaded to the computing unit 12 on the surface through the armored cable 7. The magnetic field intensity measured by the upper magnetometer 5 and the lower magnetometer 6 is the magnetic field intensity of the alternating magnetic field generated by the magnetic rotating joint 14. The magnetic field intensity B1 measured by the lower magnetometer 6 and the angles of the spatial rectangular coordinate system where the lower magnetometer 6 is located measured by the measuring node 4 relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are a, b, and c, respectively; the magnetic field intensity B2 measured by the upper magnetometer 5 and the angles of the spatial rectangular coordinate system where the upper magnetometer 5 is located measured by the measuring node 4 relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are d, e, and f, respectively.

[0069] The magnetometer 11 provided in the measuring sub 4 is used to perform measurement at the target point and the first position of the vertical well 3. The actual operation includes:

[0070] First, the measuring sub 4 is lowered to the target position of the vertical well 3 by the logging winch 9, and the magnetometer 11 in the measuring sub 4 is started. A magnetic signal generating unit is inserted into the directional well, and the magnetic rotary joint 14 is maintained to rotate at a certain speed to generate a magnetic signal to act on the docking vertical well. The magnetometer 11 in working state can measure the magnetic field strength of the magnetometer 11 at the target point in real time, and the angles of the spatial rectangular coordinate system of the magnetometer 11 measured by the measuring section 4 relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are respectively a, b, c, and the measured magnetic field strength B1 and the angles a, b, c are uploaded to the calculation unit 12 on the surface through the armored cable 7; then, after the measuring section 4 is lifted up by a distance L through the logging winch 9, the magnetometer 11 is located at the first position, and the magnetic field strength data B2 measured by the magnetometer 11 and the angles d, e, f of the spatial rectangular coordinate system of the magnetometer 11 measured by the measuring section 4 relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system are uploaded to the calculation unit 12.

[0071] In an exemplary embodiment, Figure 1 As shown, the present application provides a magnetic positioning system, which includes: the above-mentioned magnetic signal acquisition device, a magnetic signal generating unit and a calculation unit 12;

[0072] The magnetic signal generating unit is used to generate a magnetic signal, and the magnetic signal acts on the docking vertical well. Specifically, the magnetic signal generating unit includes a drill bit 13, a magnetic rotary joint 14, a bent screw drill tool 15, a non-magnetic drill collar 16 and a drill pipe column 17 connected in sequence. The drill bit 13, the magnetic rotary joint 14, the bent screw drill tool 15, the non-magnetic drill collar 16 and the drill pipe column 17 coaxially form a bottom hole drilling tool assembly axis 18. The drill bit 13, the magnetic rotary joint 14, the bent screw drill tool 15 and the non-magnetic drill collar 16 are fixed in sequence by threaded connection, and the drill pipe column 17 is driven by the surface drilling rig to drive the non-magnetic drill collar 16 and the bent screw drill tool 15 to rotate, and the mud circulation drives the bent screw drill tool 15 to drive the magnetic rotary joint 14 and the drill bit 13 to rotate together, wherein the magnetic rotary joint 14 generates an alternating magnetic field, and the drill bit 13 rotates to drill the broken formation.

[0073] A magnetic signal acquisition device is used to collect the magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well 3, respectively, wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit 1 is located and the magnetic north coordinate system when the measuring unit 1 in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotating joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the gravity direction, and the z-axis is parallel to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance.

[0074] The calculation unit 12 is connected to the magnetic signal acquisition device and is used to calculate the azimuth angle of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle.

[0075] Specifically, the azimuth and apex angle of the drill bit are obtained, and a conversion matrix is ​​determined based on the azimuth, the apex angle and the included angle; then, the position coordinates of the measuring unit in the magnetic north coordinate system are calculated based on the magnetic field strength and the conversion matrix when the measuring unit is at the target point and the first position respectively; finally, the azimuth of the magnetic rotary joint is calculated based on the preset distance and the position coordinates in the magnetic north coordinate system.

[0076] The magnetic positioning system provided in the present application can accurately calculate the azimuth of the magnetic rotating joint 14 by measuring the magnetic field strength at the target point and the first position in the docking vertical well 3, and using the magnetic field strength at different positions and the mathematical model of the magnetic field strength distribution to solve the azimuth of the magnetic rotating joint 14, thereby improving the docking accuracy of the docking vertical well 3 and the drill bit 13.

[0077] The magnetic positioning method provided in the embodiment of the present application can be applied to Figure 4In the application environment shown. Among them, the terminal 102 communicates with the server 104 through the network. The data storage system can store the data that the server 104 needs to process. The data storage system can be set up separately, or it can be integrated on the server 104, or it can be placed on the cloud or other servers. The terminal 102 can send the acquired magnetic field strength to the server 104. After the server 104 receives the magnetic field strength, the server 104 calculates the azimuth of the magnetic rotating joint in the magnetic signal generating unit based on the magnetic field strength. The server 104 can feed back the obtained azimuth of the magnetic rotating joint to the terminal 102. In addition, in some embodiments, the magnetic positioning method can also be implemented by the server 104 or the terminal 102 alone, such as the terminal 102 can directly perform magnetic positioning processing on the magnetic field strength, or the server 104 can obtain the magnetic field strength from the data storage system and calculate the azimuth of the magnetic rotating joint.

[0078] The terminal 102 may be, but is not limited to, various desktop computers, laptop computers, smart phones, and tablet computers. The server 104 may be implemented as an independent server or a server cluster consisting of multiple servers, or may be a cloud server.

[0079] In an exemplary embodiment, Figure 5 As shown, a magnetic positioning method is provided, which is executed by a computer device, and can be specifically executed by a computer device such as a terminal or a server alone, or by a terminal and a server together. The magnetic positioning method is applied to any of the magnetic positioning systems described above, and the magnetic positioning includes steps 101 to 103:

[0080] Step 101, obtaining a magnetic signal, wherein the magnetic signal acts on the docking vertical well 3. Specifically, the magnetic signal generates magnetic lines of force that act on the docking vertical well 3 through the rotation of the magnetic rotary joint 14 in the magnetic signal generating unit.

[0081] Step 102, collecting the magnetic field strength and corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well; wherein the distance between the first position and the target point is a preset distance; the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located relative to the magnetic north coordinate system when the measuring unit in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotary joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the direction of gravity, and the z-axis is perpendicular to the x-axis and the y-axis.

[0082] Step 103, calculating the azimuth of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle, specifically includes steps 201 to 204:

[0083] Step 201, obtaining the azimuth angle and vertex angle of the drill bit.

[0084] Specifically, the top angle of the drill bit 13 is measured by the measurement while drilling instrument inside the non-magnetic drill collar 11 in the directional well. The top angle is the angle between the bottom hole drill assembly axis 18 and the direction of the earth's gravity, and the azimuth is the angle between the projection of the bottom hole drill assembly axis 18 on the horizontal plane and the magnetic north direction. The measurement while drilling instrument sends the measured top angle to the surface pressure sensor by sending a mud pulse signal. In the analysis module of the ground working machine of the measurement while drilling system, the mud pulse signal received by the surface pressure sensor is sorted to obtain the circulating mud pressure conversion curve. The top angle of the drill bit is obtained based on the circulating mud pressure conversion curve, and finally the top angle of the drill bit 13 is transmitted to the calculation unit 12 through the measurement while drilling system. Because the drill bit 13 and the magnetic rotary joint 4 are coaxial, the azimuth angle and top angle of the drill bit 13 are the same as the azimuth angle and top angle of the magnetic rotary joint 4.

[0085] When encountering a magnetic field abnormal formation, the azimuth of the magnetic rotary joint 4 measured by the measurement while drilling instrument is inaccurate. Therefore, the magnetic positioning system provided by the present application is used to determine the azimuth of the magnetic rotary joint 4. Therefore, the azimuth of the drill bit 13 is unknown data at this time.

[0086] Step 202: determining a conversion matrix according to the azimuth angle, the vertex angle and the included angle.

[0087] The conversion matrix includes a first conversion matrix and a second conversion matrix. The expression of the first conversion matrix is:

[0088]

[0089] Wherein, A is the first transformation matrix, a, b, c are the angles of the x-axis, y-axis, and z-axis of the spatial rectangular coordinate system where the measuring unit 1 is located relative to the magnetic north coordinate system when the measuring unit 1 is at the target point, α0 is the top angle of the drill bit, is the azimuth angle of the magnetic rotary joint.

[0090] The expression of the second conversion matrix is:

[0091]

[0092] Wherein, B is the second transformation matrix, d, e, and f are respectively the angles of the x-axis, y-axis, and z-axis of the spatial rectangular coordinate system where the measuring unit 1 is located relative to the magnetic north coordinate system when the measuring unit 1 is in the first position.

[0093] Step 203, calculating the position coordinates of the measuring unit in the magnetic north coordinate system when the measuring unit is at the target point and the first position respectively according to the magnetic field strength and the conversion matrix, includes:

[0094] Step 2031: using the conversion matrix to convert the magnetic field strength to obtain a converted magnetic field strength, which specifically includes: using the first conversion matrix to convert the magnetic field strength B1, using the second conversion matrix to convert the magnetic field strength B2, to obtain the converted magnetic field strengths B1 and B2.

[0095] Among them, the magnetic field strength B1(B1 x 、B1 y 、B1 z ) is the magnetic field intensity collected by the magnetometer 6 or the magnetometer 11 at the first position, B1 x 、B1 y 、B1 z are the three components of the magnetic field intensity in the rectangular coordinates of the space where the magnetometer 6 or the magnetometer 11 is located, B2(B2 x 、B2 y 、B2 z ) is the magnetic field intensity collected by the magnetometer 5 or the magnetometer 11 at the target point, B2 x 、B2 y 、B2 z are the three components of the magnetic field intensity in the rectangular coordinates of the space where the magnetometer 5 or the magnetometer 11 is located. x 、B1 y 、B1 z or B2 x 、B2 y 、B2 z The conversion is performed using formula (1), which is as follows:

[0096] [B' x ; B′ y ; B' z ]=A1 -1 [B x ; B y ; B z ] (1);

[0097] Among them, B' x , B' y , B' z are the three components of the transformed magnetic field intensity, B x , B y , B z The components of the three axes in the rectangular coordinate system of the space where the magnetometer is located.

[0098] Step 2032: Calculate the position coordinates of the measuring unit in the magnetic space rectangular coordinate system when the measuring unit is at the target point and the first position according to the converted magnetic field intensity and the mathematical model of magnetic field intensity distribution. The magnetic space rectangular coordinate system takes the center of gravity of the magnetic rotary joint 14 as the origin, the straight line where the axis of the magnetic rotary joint 14 is located is the x-axis, the y-axis is perpendicular to the x-axis and in the horizontal plane, and the z-axis is perpendicular to both the y-axis and the x-axis.

[0099] Step 2033: Calculate the position coordinates of the measuring unit in the rectangular coordinate system of the magnetic space when the measuring unit is at the target point and the first position respectively according to the converted magnetic field intensity and the mathematical model of the magnetic field intensity distribution.

[0100] Specifically, the position coordinates (x'1, y'1, z'1) of the target point in the magnetic space rectangular coordinate system and the position coordinates (x'2, y'2, z'2) of the first position in the magnetic space rectangular coordinate system are calculated using the magnetic field intensity distribution mathematical model. The specific calculation process includes:

[0101] When calculating the position coordinates (x'1, y'1, z'1) of the target point in the magnetic space rectangular coordinate system, the magnetic permeability μ, magnetic moment value M and the converted magnetic field intensity B1 (B1 x 、B1 y 、B1 z ) is substituted into the mathematical model of magnetic field intensity distribution, and F(x,y,z)=0 is solved to obtain x'1, y'1, z'1, (x'1, y'1, z'1) which are the position coordinates of the target point in the rectangular coordinate system of magnetic space.

[0102] When calculating the position coordinates (x'2, y'2, z'2) of the first position in the magnetic space rectangular coordinate system, the magnetic permeability μ, magnetic moment value M and the converted magnetic field intensity B2 (B2 x 、B2 y 、B2 z ) is substituted into the mathematical model of magnetic field intensity distribution, and F(x,y,z)=0 is solved to obtain x'2, y'2, z'2, (x'2, y'2, z'2), which are the position coordinates of the first position in the rectangular coordinate system of magnetic space.

[0103] Among them, (x'1, y'1, z'1) and (x'2, y'2, z'2) are respectively the position coordinates of the target point and the first position in the magnetic space rectangular coordinate system constructed with the center of gravity of the magnetic rotary joint 14 as the origin, the x-axis of the magnetic space rectangular coordinate system is the straight line where the rotation axis of the magnetic rotary joint 14 is located, the y-axis is perpendicular to the x-axis and in the horizontal plane, and the z-axis is perpendicular to both the y-axis and the x-axis.

[0104] The expression of the mathematical model of magnetic field intensity distribution is:

[0105]

[0106] Wherein, F(x, y, z) is the mathematical model of magnetic field intensity distribution, (x, y, z) is a point in the rectangular coordinate system of the magnetic space, μ is the magnetic permeability, M is the magnetic moment value, and B' x , B' y , B' z They are the components of the magnetic field intensity at the position (x, y, z) along the three axes in the rectangular coordinate system of the magnetic space.

[0107] Step 2034: using the conversion matrix to convert the position coordinates of the magnetic space rectangular coordinate system into the position coordinates of the magnetic north coordinate system.

[0108] After obtaining the position coordinates (x'2, y'2, z'2) of the first position in the magnetic space rectangular coordinate system and the position coordinates (x'1, y'1, z'1) of the target in the magnetic space rectangular coordinate system, the first conversion matrix is ​​used to transform the position coordinates of the target in the magnetic space rectangular coordinate system to obtain the coordinate position of the target in the magnetic north coordinate system (x1, y1, z1), and the second conversion matrix is ​​used to transform the position coordinates of the first position in the magnetic space rectangular coordinate system to obtain the coordinate position of the first position in the magnetic north coordinate system (x2, y2, z2). Specifically, the conversion is performed using formulas (3) and (4), respectively, and formulas (3) and (4) are as follows:

[0109]

[0110] Among them, (x1, y1, z1) and (x2, y2, z2) are the position coordinates of the target point and the first position in the magnetic north coordinate system respectively, (x'1, y'1, z'1) and (x'2, y'2, z'2) are the position coordinates of the target point and the first position in the magnetic space rectangular coordinate system, wherein the magnetic north coordinate system takes the center of gravity of the magnetic rotating joint 14 in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the direction of gravity, and the z-axis is perpendicular to the x-axis and the y-axis.

[0111] Step 204: Calculate the azimuth of the magnetic rotary joint according to the preset distance and the position coordinates in the magnetic north coordinate system.

[0112] According to the position coordinates (x1, y1, z1) and (x2, y2, z2) of the target point and the first position in the magnetic North coordinate system, they are substituted into formula (5), and the azimuth of the magnetic rotary joint 14 is solved to obtain the azimuth of the magnetic rotary joint 4, where the preset distance L is known.

[0113]

[0114] A magnetic positioning method proposed in the present application measures multiple magnetic field intensities generated by magnetic signals at different positions in the docking vertical well 3, transforms the magnetic field intensity by using spatial coordinate transformation, and calculates the azimuth of the magnetic rotary joint 14 according to the transformed magnetic field intensity and the mathematical model of the magnetic field intensity distribution. This solves the problem that the downhole measurement instrument in magnetically abnormal formations cannot accurately measure the azimuth of the magnetic rotary joint 14 and cannot determine the relative position of the drill bit 13 with respect to the target point, resulting in the inability to locate the drill bit 13. At the same time, the azimuth of the magnetic rotary joint 14 directly calculated and obtained can more accurately reflect the azimuth of the drill bit 13, thereby improving the docking guidance accuracy of the docking vertical well project. Its promotion and application has certain engineering value.

[0115] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A magnetic signal acquisition device, characterized in that: The magnetic signal acquisition device comprises: a measurement unit and a well logging connection unit; The measuring unit is arranged in the docking vertical well, and is used to measure the magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well respectively; wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located and the magnetic north coordinate system when the measuring unit is located at the target point or the first position; the magnetic north coordinate system takes the center of gravity of the magnetic source generating the magnetic signal as the origin, the x-axis is the geomagnetic north pole, the y-axis is the direction of gravity, and the z-axis is perpendicular to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance; The logging connection unit is connected to the measuring unit and is used to adjust the position of the measuring unit in the docking vertical well.

2. The magnetic signal acquisition device according to claim 1, characterized in that: The measuring unit comprises a measuring nipple, a lower magnetometer and an upper magnetometer; The lower magnetometer is arranged in the measuring sub, located at the target point, and is used to collect the magnetic field intensity generated by the magnetic signal at the target point of the vertical well; The upper magnetometer is arranged in the measuring sub, located at the first position, and the distance between the upper magnetometer and the lower magnetometer is the preset distance, and is used to collect the magnetic field intensity generated by the magnetic signal at the first position of the docking vertical well; The measuring short section is connected to the logging connection unit and is used to measure the angles of the spatial rectangular coordinate system where the upper magnetometer is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and the angles of the spatial rectangular coordinate system where the lower magnetometer is located relative to the x-axis, y-axis and z-axis of the magnetic north coordinate system, and send the magnetic field strength and angle to the logging connection unit.

3. The magnetic signal acquisition device according to claim 1, characterized in that: The measuring unit comprises: a measuring nipple and a magnetometer; The magnetometer is arranged in the measuring sub, and is used to collect the magnetic field strength generated by the magnetic signal at the target point and the first position of the docking vertical well respectively; The measuring nipple is connected to the logging connection unit and is used to measure the angles of the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the magnetometer is located relative to the magnetic north coordinate system, and send the angles and the magnetic field strength to the logging connection unit.

4. The magnetic signal acquisition device according to claim 1, characterized in that: The logging connection unit includes an armored cable, a wellhead pulley and a logging winch; the wellhead pulley is arranged at the wellhead of the docking vertical well, the logging winch is arranged on the ground, the armored cable is wound around the body of the logging winch, one end of the armored cable passes through the wellhead pulley and is connected to the measuring unit, and the other end of the armored cable is connected to the computing unit; the logging winch is used to adjust the length of the armored cable, thereby adjusting the position of the measuring unit in the docking vertical well.

5. A magnetic positioning system, characterized in that: The magnetic positioning system comprises: the magnetic signal acquisition device according to claim 1, a magnetic signal generating unit and a computing unit; A magnetic signal generating unit, used to generate a magnetic signal, wherein the magnetic signal acts on the docking vertical well; A magnetic signal acquisition device, used for acquiring the magnetic field strength and corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well respectively; wherein the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located and the magnetic north coordinate system when the measuring unit in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotary joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the gravity direction, and the z-axis is parallel to the x-axis and the y-axis; the distance between the first position and the target point is a preset distance; A calculation unit is connected to the magnetic signal acquisition device and is used to calculate the azimuth angle of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle.

6. A magnetic positioning method, characterized in that: The magnetic positioning method comprises: Acquiring a magnetic signal, wherein the magnetic signal acts on the docking vertical well; The magnetic field strength and the corresponding angle generated by the magnetic signal at the target point and the first position of the docking vertical well are collected; wherein the distance between the first position and the target point is a preset distance; the angle is the angle between the x-axis, y-axis and z-axis of the spatial rectangular coordinate system where the measuring unit is located relative to the magnetic north coordinate system when the measuring unit in the magnetic signal acquisition device is located at the target point or the first position respectively; the magnetic north coordinate system takes the center of gravity of the magnetic rotary joint in the magnetic signal generating unit as the origin, the x-axis is the geomagnetic north pole, the y-axis is the gravity direction, and the z-axis is perpendicular to the x-axis and the y-axis; The azimuth angle of the magnetic rotary joint is calculated according to the preset distance, the magnetic field strength and the angle.

7. The magnetic positioning method according to claim 6, characterized in that: Calculating the azimuth of the magnetic rotary joint according to the preset distance, the magnetic field strength and the angle includes: Get the azimuth and top angle of the drill bit; Determine a conversion matrix according to the azimuth angle, the vertex angle and the included angle; Calculate the position coordinates of the measuring unit in the magnetic north coordinate system when the measuring unit is at the target point and the first position respectively according to the magnetic field strength and the conversion matrix; The azimuth of the magnetic rotary joint is calculated according to the preset distance and the position coordinates in the magnetic north coordinate system.

8. The magnetic positioning method according to claim 7, characterized in that: Calculating the position coordinates of the measuring unit in the magnetic north coordinate system when the measuring unit is at the target point and the first position respectively according to the magnetic field strength and the conversion matrix includes: Using the conversion matrix to convert the magnetic field intensity to obtain a converted magnetic field intensity; The position coordinates of the measuring unit in the magnetic space rectangular coordinate system are calculated according to the converted magnetic field intensity and the mathematical model of the magnetic field intensity distribution when the measuring unit is at the target point and the first position; the magnetic space rectangular coordinate system takes the center of gravity of the magnetic rotary joint as the origin, the straight line where the axis of rotation of the magnetic rotary joint is located is the x-axis, the y-axis is perpendicular to the x-axis and in the horizontal plane, and the z-axis is perpendicular to both the y-axis and the x-axis; The position coordinates of the magnetic space rectangular coordinate system are converted into position coordinates in the magnetic north coordinate system using the conversion matrix.

9. The magnetic positioning method according to claim 7, characterized in that: The conversion matrix includes a first conversion matrix and a second conversion matrix; The expression of the first conversion matrix is: Where A is the first transformation matrix, a, b, c are the angles of the x-axis, y-axis, and z-axis of the rectangular coordinate system of the measuring unit relative to the magnetic north coordinate system when the measuring unit is at the target point, α0 is the top angle of the drill bit, is the azimuth of the magnetic rotary joint; The expression of the second conversion matrix is: Wherein, B is the second transformation matrix, d, e, and f are respectively the angles of the x-axis, y-axis, and z-axis of the spatial rectangular coordinate system where the measuring unit is located relative to the magnetic north coordinate system when the measuring unit is in the first position.

10. The magnetic positioning method according to claim 8, characterized in that: The expression of the mathematical model of magnetic field intensity distribution is: Wherein, F(x, y, z) is the mathematical model of magnetic field intensity distribution, (x, y, z) is a point in the rectangular coordinate system of the magnetic space, μ is the magnetic permeability, M is the magnetic moment value, and B' x , B' y , B' z They are the components of the magnetic field intensity at the position (x, y, z) along the three axes in the rectangular coordinate system of the magnetic space.

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