Dual-transceiving multiplexing dual-frequency nuclear magnetic logging-while-drilling module and method

Abstract

The invention relates to a dual-transmit-receive multiplexing dual-frequency while-drilling nuclear magnetic logging module which comprises a probe framework, a first permanent magnet, a second permanent magnet, a first transmit-receive multiplexing coil, a second transmit-receive multiplexing coil, a first inverter circuit, a first compensation circuit, a first energy discharge circuit, a second inverter circuit, a second compensation circuit and a second energy discharge circuit. Wherein the first permanent magnet and the second permanent magnet are symmetrically arranged at two ends of the probe framework; the first transceiving multiplexing coil and the second transceiving multiplexing coil are symmetrically wound on the probe framework; the first compensation circuit is connected with the first transceiving multiplexing coil and the first energy discharge circuit, and the first energy discharge circuit is connected with the first full-bridge inverter circuit; the second compensation circuit is connected with a second transmit-receive multiplexing coil, the second compensation circuit is connected with a second energy discharge circuit, and the second energy discharge circuit is connected with a second full-bridge inverter circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of logging equipment, and particularly to a dual-transceiver multiplexing dual-frequency measurement-while-drilling nuclear magnetic logging module. Background Art

[0002] Nuclear magnetic resonance logging is a logging technology that uses the principle of nuclear magnetic resonance to measure the fluid properties in formation rocks. Its basic principle is based on the nuclear magnetic resonance phenomenon of hydrogen atomic nuclei in the formation under an external magnetic field. By measuring the signals generated by hydrogen atomic nuclei during the relaxation process, important geological parameters such as formation porosity, oil saturation, and permeability can be obtained. Compared with traditional logging methods (such as electric logging, acoustic logging, and neutron logging, etc.), nuclear magnetic resonance logging can directly measure the properties of free fluids (oil, gas, water) in any lithologic reservoir. In addition, it can work in complex downhole environments such as high temperature and high pressure, and is suitable for logging operations in deep wells and ultra-deep wells. Therefore, nuclear magnetic resonance logging has become an important method for oil logging.

[0003] In the research, it is found that the existing nuclear magnetic modules are easily affected by factors such as wellbore irregularity, hole enlargement, cycle skipping, and random noise, resulting in a reduction in the reliability of measurement results. Summary of the Invention

[0004] The present invention provides a dual-transceiver multiplexing dual-frequency measurement-while-drilling nuclear magnetic logging module, which has two antennas with dual-transceiver multiplexing and dual-frequency resonance, solves the problems of low utilization rate of coils and large influence of environmental disturbance in the prior art, and improves the reliability of measurement-while-drilling nuclear magnetic logging.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In the first aspect, the present application provides a dual-transceiver multiplexing dual-frequency measurement-while-drilling nuclear magnetic logging module, including: a probe skeleton, a first permanent magnet, a second permanent magnet, a first transceiver multiplexing coil, a second transceiver multiplexing coil, a first inverter circuit, a first compensation circuit, a first energy discharge circuit, a second inverter circuit, a second compensation circuit, and a second energy discharge circuit; wherein, The first permanent magnet and the second permanent magnet are symmetrically arranged at both ends of the probe skeleton; The first transceiver multiplexing coil and the second transceiver multiplexing coil are symmetrically wound around the probe skeleton; The first inverter circuit, the first compensation circuit, the first energy discharge circuit, and the first transceiver multiplexing coil form a signal processing channel for the first working frequency. Among them, the first compensation circuit is connected to the first transceiver multiplexing coil, the first compensation circuit is connected to the first energy discharge circuit, and the first energy discharge circuit is connected to the first full-bridge inverter circuit; The second inverter circuit, the second compensation circuit, the second energy discharge circuit, and the second transceiver-reuse coil form a signal processing channel for the second operating frequency. Among them, the second compensation circuit is connected to the second transceiver-reuse coil, the second compensation circuit is connected to the second energy discharge circuit, and the second energy discharge circuit is connected to the second full-bridge inverter circuit.

[0006] In one implementation, the first transceiver-reuse coil and the second transceiver-reuse coil are helically wound on the probe skeleton by mylar wires, and the first transceiver-reuse coil and the second transceiver-reuse coil have the same number of turns and opposite polarities.

[0007] In one implementation, the first compensation circuit includes a first capacitor C1 and a second inductor L2, where the first capacitor C1 is connected in parallel with the first transceiver-reuse coil L1, and the second inductor L2 is connected in series to the parallel point of the first inductor C1 and one end of the first transceiver-reuse coil L1.

[0008] In one implementation, the first energy discharge circuit includes a first resistor R1, a second resistor R2, a first switch S1, and a second switch S2. Among them, the first resistor R1 is connected in series with the first switch S1, the second switch S2 and the second resistor R2 are connected in series, the other end of the first resistor R1 is connected to the first inductor L2, the other end of the second resistor R2 is connected to the parallel point of the first capacitor C1 and the other end of the first transceiver-reuse coil L1, and the middle of the first switch S1 and the second switch S2 is grounded.

[0009] In one implementation, the first inverter circuit is a full-bridge inverter circuit, including four switching tubes, four diodes, and a third switch S3, and the third switch S3 is connected to the positive power supply.

[0010] In one implementation, the second compensation circuit includes a second capacitor C2 and a second inductor L4, where the second capacitor C1 is connected in parallel with the second transceiver-reuse coil L3, and the second inductor L4 is connected in series to the parallel point of the second capacitor C2 and one end of the second transceiver-reuse coil L3.

[0011] In one implementation, the second energy discharge circuit includes a third resistor R3, a fourth resistor R4, a fourth switch S4, and a fifth switch S5. Among them, the third resistor R3 is connected in series with the fourth switch S4, the fifth switch S5 and the fourth resistor R4 are connected in series, the other end of the third resistor R3 is connected to the second inductor L4, the other end of the fourth resistor R4 is connected to the parallel point of the first capacitor C2 and the other end of the second transceiver-reuse coil L2, and the middle of the fourth switch S4 and the fifth switch S5 is grounded.

[0012] In one implementation, the second inverter circuit is a full-bridge inverter circuit, and the circuit includes four switching tubes, four diodes, and a sixth switch S6, and the sixth switch S6 is connected to the positive power supply.

[0013] In one implementation, the relationship between the component parameters in the first compensation circuit and the second compensation circuit is: ; where ω 1 is the first operating angular frequency of the system, ω 2 is the second operating angular frequency of the system; The definition of the first operating angular frequency ω 1 is: ; The definition of the second operating angular frequency ω 2 is: ; where f 1 is the first operating frequency, f 2 is the second operating frequency.

[0014] The present invention also provides a working method for a dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic resonance module, which is applied to the dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic resonance module described in the first aspect. The method is characterized in that the state of the operation switch is adjusted to make the dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic resonance module in four cyclic working conditions: The third switch S3 is closed, and the first switch S1, the second switch S2, the fourth switch S4, the fifth switch S5, and the sixth switch S6 are open, and the module works in the first emission condition; The first switch S1, the second switch S2, the fourth switch S4, and the fifth switch S5 are closed, and the third switch S3 and the sixth switch S6 are open, and the module works in the first absorption condition; The sixth switch S6 is closed, and the first switch S1, the second switch S2, the third switch S3, the fourth switch S4, and the fifth switch S5 are open, and the module works in the second emission condition; The first switch S1, the second switch S2, the fourth switch S4, and the fifth switch S5 are closed, and the third switch S3 and the sixth switch S6 are open, and the module works in the second absorption condition.

[0015] Due to the above technical solutions, the present invention has the following advantages: 1. The present invention symmetrically arranges two sets of transceiver multiplexing coils with the same number of turns and opposite polarities, and obtains signals from two different emission sources at the same time, which has a superimposed enhancement effect on nuclear magnetic resonance signals. This means that the formation can be detected from different angles and positions, so as to obtain more comprehensive geological information, and can cancel the influence of instrument parameters on the system with each other, improve the speed of logging-while-drilling detection, and improve the signal quality; 2. The present invention can transmit dual-frequency signals, improve signal recognition ability, enhance the weather resistance of the logging-while-drilling nuclear magnetic resonance logging tool under high-temperature and high-pressure environments, and reduce the loss of resonance echo signal acquisition ability caused by changes in resonance frequencies.

[0016] 3. Two transceiver-reuse coils are symmetrically arranged on the probe skeleton and are at the same distance from a relatively distant interference source, capable of canceling out interference signals with each other and reducing the influence of factors such as borehole irregularity, hole enlargement, cycle skipping, and random noise on the measurement results. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of a dual-transceiver-reuse dual-frequency logging-while-drilling nuclear magnetic resonance logging module in an embodiment of the present invention; Figure 2 is an equivalent diagram of a first compensation circuit at a frequency of ω1 in an embodiment of the present invention; Figure 3 is an equivalent diagram of a first compensation circuit at a frequency of ω2 in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the scope of protection of the present invention.

[0019] In view of the defects and problems of the prior art, the present application provides a dual-transceiver-reuse dual-frequency logging-while-drilling nuclear magnetic resonance logging module, including: a probe skeleton, a first permanent magnet, a second permanent magnet, a first transceiver-reuse coil, a second transceiver-reuse coil, a first inverter circuit, a first compensation circuit, a first energy discharge circuit, a second inverter circuit, a second compensation circuit, and a second energy discharge circuit; wherein, The first permanent magnet and the second permanent magnet are symmetrically arranged at both ends of the probe skeleton; The first transceiver-reuse coil and the second transceiver-reuse coil are symmetrically wound around the probe skeleton; The first inverter circuit, the first compensation circuit, the first energy discharge circuit, and the first transceiver-reuse coil form a signal processing channel for a first operating frequency. Among them, the first compensation circuit is connected to the first transceiver-reuse coil, the first compensation circuit is connected to the first energy discharge circuit, and the first energy discharge circuit is connected to the first full-bridge inverter circuit; The second inverter circuit, the second compensation circuit, the second energy release circuit, and the second transceiver-reuse coil form a signal processing channel for the second operating frequency. Among them, the second compensation circuit is connected to the second transceiver-reuse coil, the second compensation circuit is connected to the second energy release circuit, and the second energy release circuit is connected to the second full-bridge inverter circuit.

[0020] The above modules will be described in a more detailed embodiment with reference to more drawings, and their effects will be described.

[0021] Detailed Embodiment This embodiment discloses a dual transceiver-reuse dual-frequency logging-while-drilling nuclear magnetic logging module, as Figure 1 shown, including: a probe skeleton, a first permanent magnet, a second permanent magnet, a first transceiver-reuse coil, a second transceiver-reuse coil, a first inverter circuit, a first compensation circuit, a first energy release circuit, a second inverter circuit, a second compensation circuit, and a second energy release circuit.

[0022] Among them, the first permanent magnet and the second permanent magnet are specifically distributed as a first annular permanent magnet and a second annular permanent magnet. The first inverter circuit and the second inverter circuit adopt full-bridge inverter circuits.

[0023] The first transceiver-reuse coil and the second transceiver-reuse coil are helically wound on the probe skeleton by mylar wire, and the first transceiver-reuse coil and the second transceiver-reuse coil have the same number of turns and opposite polarities.

[0024] The first compensation circuit includes a first capacitor C C1 and a second inductor L L2, where the first capacitor C C1 is connected in parallel with the first transceiver-reuse coil L L1, and the second inductor L L2 is connected in series with the first inductor C L1 and the parallel point of one end of the first transceiver-reuse coil L L1.

[0025] The first energy release circuit includes a first resistor R R1, a second resistor R R2, a first switch S S1 and a second switch S S2, where the first resistor R R1 is connected in series with the first switch S S1, the second switch S S2, and the second resistor R R2, the other end of the first resistor R R1 is connected to the first inductor L L2, and the other end of the second resistor R R2 is connected to the first capacitor C C1 and the first transceiver-reuse coilL The other parallel connection point of 1, the first switch S 1 and the second switch S The middle of 2 is grounded.

[0026] The first full-bridge inverter circuit includes four switching tubes, four diodes and the third switch S 3, the third switch S 3 is connected to the positive power supply.

[0027] The second compensation circuit includes the second capacitor C 2 and the second inductor L 4, wherein the second capacitor C 1 is in parallel with the second transceiver multiplexing coil L 3, the second inductor L 4 is in series with the second capacitor C 2 and the second transceiver multiplexing coil L One end parallel connection point of 3.

[0028] The second energy discharge circuit includes the third resistor R 3, the fourth resistor R 4, the fourth switch S 4 and the fifth switch S 5, wherein the third resistor R 3 is in series with the fourth switch S 4, the fifth switch S 5 and the fourth resistor R 4, the third resistor R The other end of 3 is connected to the second inductor L 4, the fourth resistor R The other end of 4 is connected to the first capacitor C 2 and the second transceiver multiplexing coil L The other end parallel connection point of 2, the fourth switch S 4 and the fifth switch S The middle of 5 is grounded.

[0029] The second full-bridge inverter circuit includes four switching tubes, four diodes and the sixth switch S 6, the sixth switch S 6 is connected to the positive power supply.

[0030] Figure 2 Is the equivalent diagram of the first compensation circuit at the first operating angular frequency ω 1 frequency, at this time the first transceiver multiplexing coil L 1, the first compensation capacitor C 1 and the first compensation inductor L 2 resonate, and their relationship is: ; Figure 3 is the equivalent diagram of the first compensation circuit at the second working angular frequency ω At this time, the first compensation capacitor is equivalent to the first equivalent capacitor C 11 and the second equivalent capacitor C 12 in parallel. The relationship between the component parameters in the first compensation circuit and the second compensation circuit is as follows: ; The definition of the first working angular frequency ω ω1 is: ; The definition of the second working angular frequency ω ω2 is: ; Wherein f f1 is the first working frequency, f f2 is the second working frequency.

[0031] Similarly, the second compensation network also adopts the same parameter design method.

[0032] The component parameters of the first compensation network and the second compensation network satisfy: ; The relationship between the first working frequency and the second working frequency is: .

[0033] The embodiment of the present invention also correspondingly provides a working method for the above module, including the following four cyclic working conditions: S1 The third switch S S3 is closed, and the first switch S S1, the second switch S S2, the fourth switch S S4, the fifth switch S S5 and the sixth switch S S6 are opened, and the module works in the first emission condition; S2 The first switch S S1, the second switch S S2, the fourth switch S S4 and the fifth switch S S5 are closed, and the third switch S S3 and the sixth switch S S6 are opened, and the module works in the first absorption condition; S3 The sixth switch S S6 is closed, and the first switch S S1, the second switch S S2, the third switch S3. Fourth Switch S 4 and Fifth Switch S 5 is turned off, and the module operates in the second emission condition; S4 First Switch S 1. Second Switch S 2. Fourth Switch S 4 and Fifth Switch S 5 is closed, third switch S 3 and Sixth Switch S 6 is turned off, and the module operates in the second absorption condition.

[0034] In several embodiments provided by the present invention, it should be understood that the disclosed method can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the above division of units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point, the displayed or discussed coupling or direct coupling or communication connection between each other can be through some interfaces, and the indirect coupling or communication connection of the device or unit can be in electrical, mechanical or other forms.

[0035] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module, characterized in that, Comprising: A probe skeleton, a first permanent magnet, a second permanent magnet, a first transceiver coil, a second transceiver coil, a first inverter circuit, a first compensation circuit, a first energy dissipation circuit, a second inverter circuit, a second compensation circuit, and a second energy dissipation circuit; wherein, The first permanent magnet and the second permanent magnet are symmetrically arranged at both ends of the probe skeleton; The first transceiver coil and the second transceiver coil are symmetrically wound around the probe skeleton; The first inverter circuit, the first compensation circuit, the first energy dissipation circuit, and the first transceiver coil form a signal processing channel with a first operating frequency. Among them, the first compensation circuit is connected to the first transceiver coil, the first compensation circuit is connected to the first energy dissipation circuit, and the first energy dissipation circuit is connected to the first inverter circuit; The second inverter circuit, the second compensation circuit, the second energy dissipation circuit, and the second transceiver coil form a signal processing channel with a second operating frequency. Among them, the second compensation circuit is connected to the second transceiver coil, the second compensation circuit is connected to the second energy dissipation circuit, and the second energy dissipation circuit is connected to the second inverter circuit.

2. The dual transceiver multiplexing dual-frequency while-drilling nuclear magnetic logging module according to claim 1, wherein The first transceiver coil and the second transceiver coil are helically wound around the probe skeleton by a mylar wire, and the first transceiver coil and the second transceiver coil have the same number of turns and opposite polarities.

3. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 2, wherein The first compensation circuit includes a first capacitor C1 and a second inductor L2. Among them, the first capacitor C1 is connected in parallel with the first transceiver coil L1, and the second inductor L2 is connected in series to the parallel point of the first inductor C1 and one end of the first transceiver coil L1.

4. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 3, wherein The first energy dissipation circuit includes a first resistor R1, a second resistor R2, a first switch S1, and a second switch S2. Among them, the first resistor R1 is connected in series with the first switch S1, the second switch S2 is connected in series with the second resistor R2, the other end of the first resistor R1 is connected to the first inductor L2, the other end of the second resistor R2 is connected to the parallel point of the first capacitor C1 and the other end of the first transceiver coil L1, and the middle of the first switch S1 and the second switch S2 is grounded.

5. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 4, wherein, The first inverter circuit is a full-bridge inverter circuit, including four switching tubes, four diodes, and a third switch S3. The third switch S3 is connected to the positive pole of the power supply.

6. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 3, wherein The second compensation circuit includes a second capacitor C2 and a second inductor L4. Among them, the second capacitor C1 is connected in parallel with the second transceiver coil L3, and the second inductor L4 is connected in series to the parallel point of the second capacitor C2 and one end of the second transceiver coil L3.

7. The dual-transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 6, wherein The second energy dissipation circuit includes a third resistor R3, a fourth resistor R4, a fourth switch S4, and a fifth switch S5. Among them, the third resistor R3 is connected in series with the fourth switch S4, the fifth switch S5 is connected in series with the fourth resistor R4, the other end of the third resistor R3 is connected to the second inductor L4, the other end of the fourth resistor R4 is connected to the parallel point of the first capacitor C2 and the other end of the second transceiver coil L2, and the middle of the fourth switch S4 and the fifth switch S5 is grounded.

8. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 7, wherein The second inverter circuit is a full-bridge inverter circuit, including four switching tubes, four diodes, and a sixth switch S6. The sixth switch S6 is connected to the positive pole of the power supply.

9. The dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to claim 8, wherein, The relationship between the component parameters in the first compensation circuit and the second compensation circuit is: ； Among them, ω 1 is the first working angular frequency of the system, ω 2 is the second working angular frequency of the system; The first operating angular frequency ω The definition of 1 is as follows: ； Second operating angular frequency ω The definition of 2 is as follows: ； Wherein f 1 is the first operating frequency, f 2 is the second operating frequency.

10. A working method of a dual-transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module, which is applied to the dual-transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module according to any one of claims 1 to 9, and is characterized in that, Operate the state of the switch so that the dual transceiver multiplexing dual-frequency logging-while-drilling nuclear magnetic logging module is in four cyclic working conditions: The third switch S3 is closed, and the first switch S1, the second switch S2, the fourth switch S4, the fifth switch S5, and the sixth switch S6 are open, and the module works in the first emission condition; The first switch S1, the second switch S2, the fourth switch S4, and the fifth switch S5 are closed, and the third switch S3 and the sixth switch S6 are open, and the module works in the first absorption condition; The sixth switch S6 is closed, and the first switch S1, the second switch S2, the third switch S3, the fourth switch S4, and the fifth switch S5 are open, and the module works in the second emission condition; The first switch S1, the second switch S2, the fourth switch S4, and the fifth switch S5 are closed, and the third switch S3 and the sixth switch S6 are open, and the module works in the second absorption condition.

Images