A downhole multi-source compatible measurement-while-drilling system based on grafting technology

Abstract

The present application discloses a downhole multi-source compatible measurement-while-drilling system based on grafting technology, which relates to the field of oil well drilling. The system includes an oil well drill and a ground decoder. The oil well drill comprises a shear valve type mud pulse generator, a pulse centralizer module, a grafting adapter and a directional probe connected in series in sequence. The directional probe is used to collect drilling sensing parameters through a sensor module. The grafting adapter is used to transmit the drilling sensing parameters to the shear valve type mud pulse generator. The pulse centralizer module includes a centralizer and a shock absorber. The shock absorber is used to perform adaptive shock absorption operations according to the vibration information of the oil well drill. The shear valve type mud pulse generator is used to generate a mud pressure pulse sequence according to the drilling sensing parameters. The ground decoder is used to decode the mud pressure pulse sequence to obtain corresponding drilling measurement parameters. Thus, the compatibility and synchronous transmission of multi-source sensing signals are realized, and the reliability of mud pulse signal transmission is ensured.

Description

Technical Field

[0001] This application relates to the technical field of oil well drilling, and particularly to a downhole multi-source compatible measurement-while-drilling system based on grafting technology. Background Art

[0002] In the process of oil and gas exploration, the logging-while-drilling (LWD) technology plays a crucial role and can obtain real-time data information of various downhole physical quantities, such as temperature, pressure, vibration, etc.

[0003] The traditional downhole key pulse generator relies on the dynamic characteristics of the mud fluid to transmit pulse signals. However, when working in mud, factors such as the composition, rheology, and water content of the mud will directly affect the transmission effect of the pulse signal. For example, high-viscosity substances or particulate matters in the mud will change the fluidity of the mud, thus affecting the generation and propagation of pulses and the accuracy of downhole measurement data. In particular, as the well depth increases, ultra-deep well operations usually require the use of plugging agents containing high-viscosity substances or particulate matters to solve the problem of well fluid leakage. However, these plugging agents may hinder the normal propagation of pulse signals, resulting in signal loss, attenuation, or severe distortion.

[0004] In addition, in modern oil and gas exploration, downhole measurement usually needs to collect signals from multiple sensors simultaneously (such as well inclination angle, pressure, temperature, vibration, etc.). The working principle of the downhole key pulse generator can only transmit periodic pulse signals, and there are great limitations for the transmission of multi-source sensing signals. Different sensors may output different types of data (such as continuous data, discrete data, etc.), and the downhole key pulse generator cannot effectively compatible and synchronously transmit multi-source sensing signals.

[0005] In view of the above problems, the industry has not yet proposed a better technical solution. Summary of the Invention

[0006] This application provides a downhole multi-source compatible measurement-while-drilling system based on grafting technology, which is used to at least solve the problems of unstable downhole signal transmission, insufficient measurement accuracy, or inability to compatible multi-source signals in the traditional technology.

[0007] An embodiment of the present application provides a downhole multi-source compatible measurement-while-drilling system based on grafting technology, including an oil well drill and a ground decoder. Among them, the oil well drill includes a shear valve type mud pulse generator, a pulse centralizer module, a grafting adapter, and a directional probe connected in series in sequence; the directional probe is used to collect drilling sensing parameters through a sensor module; the drilling sensing parameters include at least one of the following parameter types: well inclination angle, azimuth angle, formation temperature, oil well drill vibration information, and downhole pressure; the grafting adapter is used to transmit the drilling sensing parameters to the shear valve type mud pulse generator; the pulse centralizer module includes a centralizer and a shock absorber, and the shock absorber is used to perform adaptive shock absorption operations according to the oil well drill vibration information; the shear valve type mud pulse generator is used to generate a mud pressure pulse sequence according to the drilling sensing parameters; the ground decoder is used to decode the mud pressure pulse sequence to obtain corresponding drilling measurement parameters.

[0008] Through a downhole multi-source compatible measurement-while-drilling system based on grafting technology provided by the present application, at least the following technical effects can be achieved:

[0009] (1) By using a shear valve type mud pulse generator to replace the traditional seated key pulse generator and generate pulse signals through mechanical shearing action, the dependence on the hydrodynamic characteristics of the mud is reduced, so that stable signal transmission can still be ensured in high-viscosity mud or an environment containing particulate plugging agents.

[0010] (2) Through the grafting adapter, different types of drilling sensing parameters (such as well inclination angle, azimuth angle, formation temperature, vibration information, downhole pressure, etc.) can be effectively transmitted to the shear valve type mud pulse generator, supporting the compatible transmission of multi-source sensing signals. In addition, the shear valve type mud pulse generator can generate corresponding mud pressure pulse sequences according to multi-source sensing parameters, thus ensuring the accurate acquisition and synchronous analysis of various measurement data and meeting the requirements of parallel processing of multi-source signals in modern oil and gas exploration.

[0011] (3) Through the shock absorber set in the pulse centralizer module, an adaptive shock absorption operation can be performed according to the vibration information of the oil well drill, dynamically offsetting vibration interference, ensuring the integrity of the pulse signal, effectively reducing the interference of vibration or high-viscosity substances on the pulse signal, ensuring the stability of the pulse signal under complex working conditions, and improving the transmission accuracy of downhole measurement data. Therefore, even in the case of ultra-deep well operations and poor mud rheology, the phenomena of signal loss and attenuation can be greatly reduced, significantly improving the reliability of measurement data during the exploration process.

[0012] Through this technical solution, by comprehensively applying grafting technology, adaptive shock absorption technology, and shear valve type mud pulse generator, the compatibility and synchronous transmission of multi-source sensing signals are achieved, the reliability of mud pulse signal transmission is ensured, the adaptability and working efficiency of downhole measurement systems under complex working conditions are optimized, and the reliability and accuracy of downhole measurement data in the process of oil and gas exploration are significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0014] Figure 1 FIG. shows a schematic structural diagram of an example of a downhole multi-source compatible measurement-while-drilling system based on grafting technology according to an embodiment of the present application;

[0015] Figure 2 FIG. shows a schematic structural diagram of an example of an oil well drill;

[0016] Figure 3 FIG. shows a schematic operation flowchart of an example of determining damping adjustment weight and stiffness adjustment weight through sample learning according to an embodiment of the present application;

[0017] Figure 4 FIG. shows a schematic operation flowchart of an example of a shear valve type mud pulse generator generating a mud pressure pulse sequence according to drilling sensing parameters according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0019] It should be noted that in the current related technologies, the shear valve type mud pulse generator adopts a shear valve design. By driving a rotor to shear the mud with a motor to generate a mud pressure pulse, it is not easily blocked in the mud. Taking the rotary pulse generator launched by APS Technology Company as an example, it can provide more stable signal transmission and stronger adaptability when facing plugging agents and other mud components.

[0020] However, although the shear valve mud pulse generator has good mud adaptability, its performance in the application of the directional probe is not ideal. During the inventors' practice of this application, it was found that the working stability of the shear valve mud pulse generator is poor. Especially in complex geological conditions, its seismic resistance is weak, and when the drill has a large amplitude, the working signal will be unstable, resulting in poor accuracy of downhole measurement data.

[0021] It should be understood that the purpose of the above description of the current related technology is only to facilitate the public's better understanding of the inventive spirit and motivation of this application, and is not regarded as a limitation of this application. In addition, the technical solutions described in the above current related technology are not prior art, and may also be unpublished technical solutions, such as those under research or in the laboratory stage.

[0022] Figure 1 The schematic structural diagram of an example of a downhole multi-source compatible measurement-while-drilling system based on grafting technology according to an embodiment of this application is shown.

[0023] As Figure 1 shown, the downhole multi-source compatible measurement-while-drilling system 100 based on grafting technology includes an oil well drill 110 and a ground decoder 120.

[0024] The oil well drill 110 includes a shear valve mud pulse generator 111, a pulse centralizer module 112, a grafting adapter 113, and a directional probe 114 connected in series in sequence.

[0025] The directional probe 114 is used to collect drilling sensing parameters through a sensor module. The drilling sensing parameters include at least one of the following parameter types: well inclination angle, azimuth angle, formation temperature, oil well drill vibration information, and downhole pressure.

[0026] Specifically, the directional probe is a high-precision detection device applied to oil and gas exploration. Its instrument types can be diversified, such as Tolteq, KeyDrill, GE probe, etc. It has high working stability, accuracy, and temperature resistance, and can provide more accurate formation information in the downhole working environment to ensure the accuracy of measurement.

[0027] In addition, the sensor module can perform downhole measurements by using high-precision sensors (such as MEMS accelerometers, temperature sensors, pressure sensors, etc.), and corresponding sampling frequencies can be set for different types of sensing parameters to ensure the accuracy of sensing measurements. Thus, by combining the directional probe and the sensor module, downhole multi-source data can be collected accurately and in real time.

[0028] The grafting adapter 113 is used to transmit the drilling sensing parameters to the shear valve mud pulse generator 111.

[0029] Here, the grafting adapter provides an interface for each sensor, enabling the sensing signal to be transmitted to the grafting adapter. In addition, multiplexing techniques (such as time-division multiplexing TDM or frequency-division multiplexing FDM) can be used to fuse multi-source signals into a single data stream and relay it to the shear-valve mud pulse generator, achieving efficient fusion and transmission of multi-source sensing signals.

[0030] The pulse straightening module 112 includes a centralizer 1121 and a shock absorber 1123. The shock absorber 1123 is used to perform adaptive shock absorption operations based on the vibration information of the oil well driller.

[0031] Specifically, the main function of the centralizer 1121 is to ensure the stability and directionality of the pulse generator, preventing the pulse signal from deviating from the predetermined path due to downhole mud flow or vibration. The shock absorber 1123 can be adjusted in real time based on the vibration information of the driller. Using advanced adaptive shock absorption technology, it automatically adjusts the shock absorption force according to real-time vibration data, minimizing the interference of vibration on the pulse signal.

[0032] In particular, as introduced above, the shear-valve mud pulse generator has relatively weak seismic resistance. In the case where the driller has a large amplitude, the vibration noise signal will damage the integrity of the mud pulse, resulting in poor accuracy of downhole measurement data.

[0033] By setting a shock absorber in the pulse straightening module, it can perform adaptive shock absorption operations according to the vibration information of the oil well driller, dynamically canceling vibration interference, ensuring the integrity of the pulse signal, effectively reducing the interference of vibration or high-viscosity substances on the pulse signal, ensuring the stability of the pulse signal under complex working conditions, and improving the transmission accuracy of downhole measurement data. Therefore, even in the case of ultra-deep well operations and poor mud rheology, the phenomena of signal loss and attenuation can be greatly reduced, significantly improving the reliability of measurement data during exploration. Through real-time shock absorption control, the accuracy of downhole measurement data is ensured, and signal attenuation or distortion is avoided.

[0034] The shear-valve mud pulse generator 111 is used to generate a mud pressure pulse sequence according to drilling sensing parameters.

[0035] Here, by using a shear-valve mud pulse generator to replace the traditional down-seating key pulse generator, a pulse signal is generated through mechanical shearing action, reducing the dependence on the hydrodynamic characteristics of the mud, and thus ensuring the stable transmission of the signal in high-viscosity mud or an environment containing particulate plugging agents.

[0036] Specifically, after receiving the multi-source drilling sensing parameters transmitted by the grafting adapter, the shear valve type mud pulse generator drives the rotor to shear the mud through the motor to generate pressure pulses, and generates corresponding mud pressure pulse sequences according to the multi-source sensing signals transmitted by the grafting adapter, thereby ensuring the accurate acquisition and synchronous analysis of various measurement data and meeting the requirements for parallel processing of multi-source signals in modern oil and gas exploration.

[0037] The surface decoder 120 is used to decode the mud pressure pulse sequence to obtain corresponding drilling measurement parameters.

[0038] Here, the surface decoder can restore the drilling measurement parameters through decoding algorithms. For example, by adopting techniques such as pulse frequency analysis and amplitude modulation decoding, various physical quantities downhole can be extracted from complex pulse signals. In addition, adaptive filtering techniques can be used to eliminate noise interference in the mud environment and improve decoding accuracy.

[0039] Through the embodiments of the present application, by combining the shear valve type mud pulse generator with the pulse centralizer module, grafting adapter and directional probe, it can work stably under complex well conditions, while ensuring the synchronous transmission and high-precision decoding of multi-source signals. Thereby, the data acquisition accuracy, real-time performance and reliability in the oil and gas exploration process have been significantly improved. Especially under complex geological conditions, the seismic resistance and adaptability of the system have been enhanced, providing stronger technical support for oil and gas exploration.

[0040] Figure 2 The structural schematic diagram of an example of an oil well drill according to an embodiment of the present application is shown.

[0041] As Figure 2 shown, a tail vertebra 115 and a battery module 116 are also provided in the oil well drill 110.

[0042] Specifically, the tail vertebra 115 is a sealing joint matching the directional probe 114 and is used to centralize the directional probe 114. Exemplarily, the tail vertebra 115 can be made of high-strength materials (such as titanium alloy or high-strength steel) to ensure its durability in the complex downhole environment. Its internal design has a sealing structure to prevent mud or other impurities from invading. In addition, the tail vertebra 115 dynamically centralizes the directional probe 114 through a mechanical structure (such as a spring or a hydraulic device) to ensure its stability during drilling, and its centralizing function can effectively reduce the sway of the directional probe 114 during drilling.

[0043] The battery module 116 is connected in series between the pulse centralizer module 112 and the grafting adapter 113. The battery module 116 includes a plurality of serially connected power supply units (not shown), and each power supply unit includes a battery and a battery centralizer, providing stable power supply for the system.

[0044] Here, the battery can be a high-energy density lithium battery or a high-temperature resistant battery to ensure stable operation in the high-temperature and high-pressure environment downhole. In addition, the battery centralizer can dynamically centralize the battery through a mechanical structure (such as a spring or a hydraulic device) to prevent the battery from being damaged due to vibration during the drilling process. In some cases, each power supply unit can also be designed in a main and standby power supply mode. When it is detected that the main battery has insufficient power or a battery failure, it can automatically switch to the standby power supply unit to provide power supply to ensure the continuity of power supply.

[0045] Regarding the details of the adaptive shock absorption operation, the working state of the shock absorption system is adjusted in real time according to the vibration signal of the drilling tool. Specifically, based on the monitored vibration information (vibration frequency and amplitude), the parameters of the shock absorber will be dynamically adjusted, thereby achieving adaptive shock absorption and reducing the interference of the vibration of the drilling tool on the mud pulse generator and the downhole measurement system.

[0046] In some embodiments, the vibration frequency and amplitude are extracted from the time-domain signal of the vibration information of the oil well driller, and the damping coefficient or stiffness coefficient of the shock absorber is adjusted in real time according to the extracted vibration frequency and amplitude:

[0047] , Equation (1)

[0048] , Equation (2)

[0049] In the formula, is the damping coefficient at time , is the basic damping coefficient, is the damping adjustment weight, is the amplitude at time ; is the stiffness coefficient at time , is the basic stiffness coefficient, is the stiffness adjustment weight, is the vibration frequency at time .

[0050] In the embodiments of the present application, the vibration information of the downhole tool is monitored and fed back to the shock absorber system. When the vibration amplitude or the vibration frequency changes, the system calculates the new shock absorber parameters (that is, the damping coefficient and the stiffness coefficient ), and then adjusts the working state of the shock absorber, so that the shock absorber can adaptively adjust its shock absorption performance according to different drilling operation conditions (such as different depths, formation properties, drilling methods, etc.), and can effectively cope with complex and changeable geological conditions and downhole vibrations.

[0051] In combination with the business scenario, during the operation of the oil well drill, when the vibration frequency is high (for example, in harder formations or during rapid drilling), the system will increase the damping coefficient , to reduce the vibration response of the system; while when the vibration amplitude is large (for example, when encountering softer formations or areas with complex geology), the stiffness coefficient is appropriately increased , to prevent the shock absorber from being unable to provide sufficient support due to excessive shock absorption.

[0052] Through the embodiments of the present application, by adjusting the damping coefficient and stiffness coefficient of the shock absorber in real time, it is possible to perform adaptive shock absorption for different vibration characteristics (such as vibration frequency and amplitude), effectively improving the shock absorption effect of the system, ensuring the stability of the mud pulse signal, and maintaining the high precision and reliability of downhole measurement data under various types of complex geological conditions.

[0053] Regarding the damping adjustment weight and stiffness adjustment weight in the above formulas (1) and (2), on the one hand, they can be set by the user, and on the other hand, they can also be determined through sample learning, and both are within the scope of implementation of the embodiments of the present application.

[0054] Figure 3 Fig. shows an operation flow chart of an example of determining the damping adjustment weight and stiffness adjustment weight through sample learning according to an embodiment of the present application.

[0055] As Figure 3 shown, in step S310, a vibration pulse sample set is obtained, and a shock absorption parameter optimization operation is performed for each vibration pulse sample in the vibration pulse sample set.

[0056] Here, during the drilling operation, the downhole sensor module continuously collects the vibration signals of the drill, combines with the mud pressure pulses generated by the shear valve type mud pulse generator, and constructs a sample set together with the state parameters of the shock absorber to facilitate optimizing the working state of the shock absorber.

[0057] In some embodiments, the input state is defined according to the vibration frequency, amplitude, shock absorber damping coefficient, and shock absorber stiffness coefficient in the vibration pulse sample, so as to determine the corresponding output action group through reinforcement learning, and each output action in the output action group is used to indicate the corresponding damping coefficient adjustment amplitude and stiffness coefficient adjustment amplitude.

[0058] Here, for each vibration pulse sample, the system performs a shock absorption parameter tuning operation to adjust the damping coefficient and stiffness coefficient of the shock absorber. The tuning process is based on reinforcement learning technology, and through a feedback mechanism, the parameters of the shock absorber are gradually optimized to reduce the interference of vibration on equipment and signal transmission during drilling.

[0059] More specifically, using the diversified parameter selection in the input state, the current environmental state of the shock absorption system is comprehensively described, providing sufficient conditional information for reinforcement learning. Furthermore, through reinforcement learning algorithms (such as Q-Learning or deep reinforcement learning), an output action group is determined, and the shock absorption parameters are dynamically optimized through interaction with the environment to adapt to complex vibration conditions, and multiple potential adjustment schemes are provided through the output action group.

[0060] Furthermore, the pulse signals after applying each output action in the output action group are obtained, and the pulse signal distortion degree is calculated by combining with the initial pulse signal in the vibration pulse sample. The corresponding target damping coefficient adjustment amplitude and target stiffness coefficient adjustment amplitude are determined according to the target output action with the smallest pulse signal distortion degree in the output action group.

[0061] More specifically, for each output action in the output action group, a shock absorber with adjusted damping coefficient and stiffness coefficient is applied, and the corresponding pulse signal (such as the pulse signal received by the surface decoder) is collected. This pulse signal is compared with the initial pulse signal (i.e., the mud pressure pulse signal generated by the shear valve mud pulse generator recorded in the sample) to obtain the corresponding pulse signal distortion degree. Furthermore, according to the distortion degree, the signal distortion degrees caused by different output actions are compared, and the output action with the smallest distortion degree is selected as the target output action.

[0062] Exemplarily, the target output action can be automatically adjusted through the reward mechanism in the reinforcement learning algorithm. For example, the reward function is designed as a function negatively correlated with the distortion degree, so that the smaller the distortion degree, the larger the reward value. Therefore, through reinforcement learning, the optimal damping coefficient adjustment amplitude and stiffness coefficient adjustment amplitude under the environmental conditions indicated by the sample can be automatically selected.

[0063] In some examples of the embodiments of the present application, the calculation formula of the pulse signal distortion degree is:

[0064] , Equation (3)

[0065] In the formula, represents the output action at time corresponding to the pulse signal distortion degree, represents at time applying the output action the obtained pulse signal, represents the distortion analysis time window, represents at the moment of the initial pulse signal.

[0066] In Equation (3), by integrating to calculate the pulse signal and the initial pulse signal the difference between them is calculated to quantify the degree of distortion. In addition, by using the squared error to measure the signal difference, it is ensured that the calculation of the distortion degree is more sensitive to larger differences. The distortion analysis time window is the time range used to calculate the distortion degree, which can be set according to the period and vibration characteristics of the pulse signal and can be dynamically adjusted.

[0067] Through the above Equation (3), the distortion degree quantifies the difference between the pulse signal after applying the output action and the initial pulse signal and then by minimizing the distortion degree it is ensured that the pulse signal after applying the output action is as close as possible to the initial pulse signal, thereby reducing signal distortion. In addition, the adjustment amplitude of the damping coefficient and the adjustment amplitude of the stiffness coefficient indicated by the output action will affect the shock absorption effect, and thus affect the shape of the pulse signal By calculating the distortion degree, the system can evaluate the pulse anti-distortion effects of different shock absorption parameter adjustment schemes, so as to select the optimal output action.

[0068] In step S320, according to the current damping coefficient of the shock absorber and the corresponding target damping coefficient adjustment amplitude in each vibration pulse sample, the damping adjustment weight is calculated, and according to the current stiffness coefficient of the shock absorber and the corresponding target stiffness coefficient adjustment amplitude in each vibration pulse sample, the stiffness adjustment weight is calculated.

[0069] Referring to the descriptions of the above Equations (1) and (2), through each sample in the vibration pulse sample set, the difference between the current damping coefficient of the shock absorber and the target damping coefficient is calculated, and this difference determines the damping adjustment weight. By statistically calculating the shock absorber parameter adjustment weights indicated by all samples in the vibration pulse sample set, such as averaging all samples, etc., to obtain the final corresponding damping adjustment weight and the stiffness adjustment weight which can reflect the adjustment trends of the damping coefficient and the stiffness coefficient under different vibration conditions.

[0070] Through the embodiments of the present application, by adopting the sample learning method, the parameters of the shock absorber can be optimized in real time according to the actually collected vibration pulse samples, improving the adaptability of the shock absorber to different downhole environments and drilling conditions. In addition, through reinforcement learning to compare different output actions and distortion degrees, the optimal shock absorption parameter adjustment strategy can be quickly found, greatly improving the dynamic response ability of the system. Thus, based on the automatic optimization mechanism of sample learning, the continuously changing vibration characteristics during the drilling process can be dealt with in real time, reducing the need for human intervention.

[0071] In some examples of the embodiments of the present application,

[0072] The calculation formula for the damping adjustment weight and the stiffness adjustment weight is as follows:

[0073] , Equation (4)

[0074] , Equation (5)

[0075] , Equation (6)

[0076] Wherein, represents the pulse signal distortion degree corresponding to the target output action of the sample at time , represents the feedback factor, represents the sample at time the target damping coefficient adjustment amplitude of, represents the sample at time the target stiffness coefficient adjustment amplitude of, represents the sample at time the amplitude of, represents the sample at time the stiffness coefficient of, represents the reference maximum distortion degree.

[0077] Here, the feedback factor is adjusted according to the distortion degree , the purpose is to dynamically correct the weight according to the distortion degree of each sample, reflecting the pulse distortion degree of the sample. In addition, when calculating the damping adjustment weight and the stiffness adjustment weight, by weighting the feedback factor of each sample, combined with its adjustment amplitude or , and normalize according to the magnitude of the vibration amplitude or the stiffness coefficient, which can ensure that the influence degree of each sample is reasonably reflected in the final weight.

[0078] Through the embodiments of the present application, dynamically adjusting the working parameters of the shock absorber according to the actual vibration pulse samples can effectively cope with the complex and changeable geological environment and vibration modes during the drilling process, ensuring that the shock absorber can maintain the optimal state. In addition, by calculating the feedback factor according to the pulse distortion degree, the system can effectively adjust the damping and stiffness, minimize the vibration interference, and improve the shock absorption effect of the system; adjusting the parameters of the shock absorber according to the feedback of the pulse signal distortion degree can greatly reduce the distortion of the mud pulse signal and improve the accuracy and reliability of the downhole measurement data.

[0079] Figure 4 Shows an operation flowchart of an example of a shear valve type mud pulse generator generating a mud pressure pulse sequence according to drilling sensing parameters according to an embodiment of the present application.

[0080] As Figure 4 shown, in step S410, for at least one sensing parameter value in the drilling sensing parameters, call the corresponding coding method according to the sensing parameter type of the sensing parameter value to perform coding processing on the sensing parameter value to determine the corresponding coding sub-frame, and configure the corresponding transmission time slot for the coding sub-frame according to the sensing parameter time slot relationship table and the sensing parameter type of the sensing parameter value.

[0081] In some embodiments, data of various parameters during the drilling process are obtained through a downhole sensor module. These parameters may include well inclination angle, azimuth angle, temperature, pressure, vibration, etc. The types and values of each parameter are different. Select a suitable coding method according to the type of sensing parameter (such as temperature, pressure, vibration, etc.). For example, temperature and pressure may use continuous value coding, while vibration and well inclination angle may use discrete value coding. Thus, selecting a suitable coding method for different types of drilling sensing parameters can compress data to the greatest extent and improve the transmission efficiency of the signal.

[0082] In addition, a variety of sensing parameter types and corresponding transmission time slots of durations are pre-stored in the sensing parameter time slot relationship table, that is, the association relationships between a variety of sensing parameter types and transmission time slot durations are recorded. Exemplarily, the transmission time of the mud pulse signal is divided into multiple time slots, and each time slot is assigned to different sensor data. For example, high-priority data (such as well inclination angle, azimuth angle) is assigned more time slots to ensure its real-time performance; low-priority data (such as temperature, pressure) is assigned fewer time slots, but the accuracy is improved through multiple transmissions. Thus, appropriate transmission time slots are respectively assigned to the coding sub-frames of each sensing type, ensuring the reliable transmission of various sensing data and reducing the error during the transmission process.

[0083] In step S420, each encoded sub-frame is combined to determine the corresponding drilling sensing encoded frame.

[0084] In some embodiments, these encoded sub-frames are combined in a predetermined order, such as a preset sensing type arrangement order, so as to obtain the corresponding drilling sensing encoded frame, ensuring that various sensing parameters can be transmitted in a specified order.

[0085] In step S430, the drilling sensing encoded frame is divided into multiple data segments, and each data segment is mapped to the position information of the pulse based on the pulse position modulation method to generate the corresponding mud pressure pulse sequence.

[0086] It should be noted that the pulse modulation methods are diverse, such as Pulse Position Modulation (PPM), Pulse Width Modulation (PWM), and Pulse Amplitude Modulation (PAM), etc. In the embodiments of the present application, due to the complexity of the mud environment, PPM applicable to low-bandwidth environments is adopted, and it is not sensitive to amplitude changes and has strong anti-interference ability. Specifically, the drilling sensing encoded frame is divided into multiple data segments, and each data segment contains a certain amount of sensing parameter data. Through this division, the transmission of data in the pulse signal can be made more efficient, and each data segment corresponds to a position in the pulse signal.

[0087] In some embodiments, when generating the pulse sequence in the mud, the position of each pulse is adjusted according to the content of the data segment. For example, a specific value of a certain data segment may correspond to a specific position or the occurrence time in the pulse signal. Furthermore, each data segment is mapped to the mud pressure pulse in turn according to the rules of pulse position modulation to form a complete mud pressure pulse sequence for transmission between downhole equipment and the ground decoder.

[0088] Through the embodiments of the present application, a large amount of sensing data is compressed into a sequence of mud pressure pulses by the pulse position modulation method. Compared with other modulation methods (such as amplitude modulation), it has stronger robustness to interference factors such as downhole vibration and noise. By changing the position rather than the amplitude of the pulse, data can be transmitted more stably, reducing signal loss and distortion, and ensuring the stable propagation of the mud pulse signal downhole.

[0089] Regarding the details of the segmentation operation of the data segments of the drilling sensing encoded frame, it should be noted that the traditional fixed frame segmentation method may cause some data segments to be too long or too short, affecting the transmission efficiency. In addition, in the mud environment, the propagation characteristics of the pulse signal may change over time, and the segmentation strategy needs to be dynamically adjusted.

[0090] In view of this, in the embodiments of the present application, it is proposed to dynamically adjust the data segmentation length according to the channel state to maximize the data transmission efficiency. Thus, according to the real-time changes of the mud channel, the segmentation strategy is dynamically adjusted to ensure the reliability of data transmission.

[0091] In some embodiments, first, receive the real-time distortion degree of the pulse signal and the real-time signal-to-noise ratio of the channel for the mud transmission channel from the ground decoder, and dynamically adjust the data segmentation length used for data segment division according to the received real-time distortion degree of the pulse signal and the real-time signal-to-noise ratio of the channel.

[0092] Here, receiving the real-time distortion degree and the real-time signal-to-noise ratio of the mud transmission channel from the ground decoder provides real-time channel state information, which provides a basis for dynamic segmentation optimization, ensuring that the segmentation strategy can adapt to the dynamic changes of the channel.

[0093] Then, divide the drilling sensing coding frame into multiple data segments according to the data segmentation length.

[0094] Here, dividing the drilling sensing coding frame into multiple data segments according to the dynamically adjusted data segmentation length ensures the optimization of the segmentation strategy, can effectively improve the data transmission efficiency, reduce the impact of too long or too short data segments on the transmission efficiency, ensure the reliability of data transmission, and can adapt to the dynamic changes of the mud channel.

[0095] Specifically, the calculation formula for the data segmentation length is:

[0096] , Equation (7)

[0097] , Equation (8)

[0098] In the formula, is the basic segmentation length, is the dynamically adjusted data segmentation length, is the adjustment coefficient, is the real-time transmission quality index of the channel, represents the real-time signal-to-noise ratio of the channel, represents the real-time distortion degree of the pulse signal.

[0099] Through the embodiments of the present application, receive real-time channel state information through the ground decoder, dynamically adjust the frame data segmentation strategy, ensure the optimization of the segmentation strategy. For example, when the channel quality is poor, increase the segmentation length to improve the transmission efficiency; when the channel quality is good, reduce the segmentation length to improve the transmission speed, thereby reducing the distortion of the pulse signal in the mud channel and ensuring the reliability of data transmission.

[0100] In some examples of the embodiments of the present application, the pulse position modulation method is an adaptive pulse modulation method based on channel state feedback. In a dynamic drilling environment, different data values are reflected by adjusting the position of the pulse.

[0101] More specifically, the pulse position corresponding to each data segment is determined by the following formula:

[0102] , Equation (9)

[0103] In the formula, represents the data segment length of the m th data segment, represents the maximum limit value of the data segment length, represents the pulse position corresponding to the m th data segment, represents the pulse period length, represents the channel state feedback adjustment coefficient.

[0104] Regarding the description of Equation (9), the pulse period length defines the time occupied by each pulse signal. By adjusting the pulse period, the data transmission rate and the stability of the pulse signal can be controlled. For example, a shorter pulse period may represent high efficiency of data transmission, but may sacrifice data accuracy; a longer pulse period may improve data accuracy, but may result in a decrease in the transmission rate. In addition, the channel state feedback adjustment coefficient reflects the adjustment amplitude for adjusting the pulse position according to the channel transmission state, and it can be preset.

[0105] Here, the specific pulse position of each data segment is determined by considering the length of the data segment and the channel quality. Specifically, in the pulse position modulation process, the pulse position is associated with the data segment length. First, the relative pulse position of the data segment is determined by the ratio of the data segment length to the maximum data segment length, so as to ensure that the position of each data segment in the pulse sequence is proportional to its length. In addition, the quality of the channel directly affects the accuracy of the pulse position. If the channel quality is poor, the adjustment amplitude of the pulse is increased through the feedback adjustment coefficient and the channel state feedback coefficient to ensure that the data can be transmitted correctly even in an unstable channel environment.

[0106] Through the embodiments of the present application, by adjusting in real time according to the feedback of the channel quality, it is possible to dynamically adjust the position of the pulse signal during the drilling process, adaptively counteract the complex noise and vibration interference in the downhole environment, increase the adjustment amplitude when the channel quality is poor to ensure the correct transmission of the signal; while when the channel quality is good, reduce the adjustment amplitude, thereby improving the transmission efficiency. Thus, based on the feedback mechanism of the channel state, it is ensured that the data is not easily lost or mis-coded during the signal transmission process, thereby improving the accuracy and reliability of the downhole measurement data.

[0107] It should be noted that, for the foregoing system embodiments, for the sake of simple description, they are all expressed as a series of actions combined. However, those skilled in the art should know that the present application is not limited by the described action sequence, because according to the present application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the present application. In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0108] The system embodiments described above are only illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0109] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the essence of the above technical solution, or the part that contributes to the related technology, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the systems described in each embodiment or some parts of the embodiments.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A downhole multi-source compatible measurement while drilling system based on grafting technology, comprising an oil well driller and a ground decoder, characterized in that: The oil well drilling device comprises a shear valve type mud pulse generator, a pulse righting module, a grafting conversion joint and a directional probe which are sequentially connected in series; The directional probe is used to collect drilling sensor parameters through the sensor module; the drilling sensor parameters include at least one of the following parameter types: well inclination angle, azimuth angle, formation temperature, oil well driller vibration information and downhole pressure; The grafting conversion joint is used to transmit the drilling sensor parameters to the shear valve type mud pulse generator; The impulse righting module comprises a righting device and a shock absorber, wherein the shock absorber is used to perform an adaptive shock absorption operation according to the vibration information of the oil well driller; The shear valve type mud pulse generator is used to generate a mud pressure pulse sequence according to the drilling sensor parameters; The surface decoder is used to decode the mud pressure pulse sequence to obtain corresponding drilling measurement parameters; The shear valve type mud pulse generator is used to generate a mud pressure pulse sequence according to the drilling sensor parameters, including: The shear valve mud pulse generator is used to perform the following operations: For at least one sensing parameter value of the drilling sensing parameters, a corresponding encoding method is called according to the sensing parameter type of the sensing parameter value to encode the sensing parameter value to determine a corresponding encoding subframe, and a corresponding transmission time slot is configured for the encoding subframe according to a sensing parameter time slot relationship table and the sensing parameter type of the sensing parameter value; the sensing parameter time slot relationship table pre-stores a plurality of sensing parameter types and transmission time slots of corresponding durations; Combining the respective coding subframes to determine a corresponding drilling sensing coding frame; Dividing the drilling sensor coding frame into a plurality of data segments, and mapping each data segment into pulse position information based on a pulse position modulation method to generate a corresponding mud pressure pulse sequence; The shock absorber is used to perform an adaptive shock absorption operation according to the vibration information of the oil well driller, including: Extract the vibration frequency and amplitude from the time domain signal of the oil well driller vibration information, and adjust the damping coefficient or stiffness coefficient of the shock absorber in real time according to the extracted vibration frequency and amplitude: ， ， In the formula, It's time The damping coefficient, is the basic damping coefficient, is the damping adjustment weight, It's time Amplitude of It's time The stiffness coefficient, is the foundation stiffness coefficient, is the stiffness adjustment weight, It's time The vibration frequency; Wherein, the determination of the damping adjustment weight and the stiffness adjustment weight includes: Obtain a vibration pulse sample set, and perform a vibration reduction parameter tuning operation for each vibration pulse sample in the vibration pulse sample set: An input state is defined according to the vibration frequency, amplitude, shock absorber damping coefficient and shock absorber stiffness coefficient in the vibration pulse sample to determine a corresponding output action group through reinforcement learning; each output action in the output action group is used to indicate a corresponding damping coefficient adjustment amplitude and a stiffness coefficient adjustment amplitude respectively; Obtaining pulse signals after applying each of the output actions in the output action group, respectively, and calculating the pulse signal distortion in combination with the initial pulse signal in the vibration pulse sample, and determining the corresponding target damping coefficient adjustment amplitude and target stiffness coefficient adjustment amplitude according to the target output action in the output action group corresponding to the minimum pulse signal distortion; Calculating a damping adjustment weight according to a current damping coefficient of the shock absorber in each of the vibration pulse samples and a corresponding target damping coefficient adjustment range, and calculating a stiffness adjustment weight according to a current stiffness coefficient of the shock absorber in each of the vibration pulse samples and a corresponding target stiffness coefficient adjustment range; Among them, the calculation formula of pulse signal distortion is: ， In the formula, Indicates output action At the moment The corresponding pulse signal distortion, Indicates at time Apply output actions The pulse signal obtained is represents the distortion analysis time window, Indicates at time The initial pulse signal; Among them, the damping adjustment weight and stiffness adjustment weights The calculation formula is: ， ， ， In the formula, Representation sample At the moment The pulse signal distortion corresponding to the target output action, represents the feedback factor, Representation sample At the moment The target damping coefficient adjustment range is Representation sample At the moment The target stiffness coefficient adjustment range is Representation sample At the moment The amplitude of Representation sample At the moment The stiffness coefficient, Indicates the reference maximum distortion.

2. The system according to claim 1, characterized in that The step of dividing the drilling sensor coding frame into a plurality of data segments comprises: receiving a real-time distortion degree of a pulse signal and a real-time signal-to-noise ratio of a channel for a mud transmission channel from a ground decoder, and dynamically adjusting a data segment length for data segment division according to the received real-time distortion degree of the pulse signal and the real-time signal-to-noise ratio of the channel; Dividing the drilling sensor coding frame into a plurality of data segments according to the data segment length; The calculation formula of the data segment length is: ， ， In the formula, is the basic segment length, is the dynamically adjusted data segment length, is the adjustment factor, It is the real-time transmission quality indicator of the channel. Indicates the real-time signal-to-noise ratio of the channel, Indicates the real-time distortion of the pulse signal.

3. The system according to claim 2, characterized in that The pulse position modulation mode is an adaptive pulse modulation mode based on channel state feedback; The method of mapping each data segment into pulse position information based on the pulse position modulation method to generate a corresponding mud pressure pulse sequence includes: The pulse position corresponding to each data segment is determined by the following formula: ， In the formula, Indicates m The data segment length of each data segment, Indicates the maximum limit of the data segment length. Indicates m The pulse position corresponding to each data segment, represents the pulse cycle length, Represents the channel state feedback adjustment coefficient.

4. The system according to claim 1, characterized in that The system also includes a tail cone; the tail cone is a sealing joint matched with the directional probe and is used to straighten the directional probe.

5. The system according to claim 1, characterized in that The system also includes a battery module connected in series between the pulse straightening module and the grafting conversion joint, the battery module includes a plurality of power supply units connected in series, and each of the power supply units includes a battery and a battery straightener.

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