Wave code wireless measurement while drilling method and system

Abstract

The invention discloses a wave code wireless measurement while drilling method, which comprises the following steps: receiving a measurement instruction, and encoding the measurement instruction according to a preset encoding mode to obtain an encoding result; pressure fluctuation corresponding to the encoding result is generated according to the encoding result through an orifice electromagnetic valve; obtaining pressure fluctuation, and decoding the pressure fluctuation according to a preset decoding mode to obtain an operation instruction; the drilling tool is operated according to the operation instruction, and attitude angle information corresponding to the drilling tool is obtained; the attitude angle information is coded according to a preset coding mode, and water flow fluctuation in the drill rod is generated according to a coding result of the attitude angle information; flow fluctuation of water flow in the drill rod is obtained through an orifice flow measurement module; the fluctuation of the water flow in the drill rod is decoded according to a preset decoding mode through a signal processing module, and original attitude information of the drilling tool is obtained; and solving the original attitude information through the industrial personal computer to obtain real-time track information of the drilling tool. According to the invention, the universality of coal mine underground measurement-while-drilling data transmission can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of downhole measurement while drilling in coal mines, and relates to a wave code wireless measurement while drilling method and system. Background Art

[0002] To ensure the safe mining of coal mines, a large number of gas drainage holes and water exploration and drainage holes usually need to be constructed underground in coal mines. Directional drilling can improve the construction quality of such holes, measure main parameters such as the inclination angle, azimuth angle, and tool face angle of the hole in real time, draw the hole trajectory and adjust the drilling attitude as needed, realize the efficient utilization of gas drainage, and achieve advanced, regional, and precise disaster prevention and control. The measurement while drilling system is a necessary support for directional drilling construction. It is applied to various directional drilling rigs underground in coal mines to measure the hole trajectory in real time to guide the design and construction of the hole.

[0003] At present, most of the measurement while drilling underground in coal mines uses a wired method to transmit the measured attitude data to the hole mouth, and a special through-cable drill pipe is used to form a transmission channel. However, the processing technology of the through-cable drill pipe is complex, the cost is expensive, and its transmission quality is greatly affected by the sealing condition at the joint.

[0004] The existing wireless measurement while drilling technology commonly uses mud pulse to form a transmission channel or an electromagnetic wave method to form a transmission channel. The electromagnetic wave transmission method is greatly affected by the formation resistance and cannot be transmitted when encountering a formation fault, so its application is relatively limited. The mud pulse transmission method requires the use of a mud pulse generator. The mud pulse generator has poor anti-vibration performance and high requirements for drilling fluid, and there are also application limitations.

[0005] The transmission channel formed by wave code is not affected by drilling fluid and formation faults, and can better meet the environmental requirements. Summary of the Invention

[0006] In view of the above deficiencies in the prior art, a wave code wireless measurement while drilling method and system provided by the present invention solve the problem that the data transmission method of measurement while drilling underground in coal mines in the prior art is severely restricted in practical applications.

[0007] To achieve the above invention purpose, the technical solution adopted by the present invention is as follows: In the first aspect, a wave code wireless measurement while drilling method, which is applied to a wave code wireless measurement while drilling system, includes:

[0008] S1. In response to an operator inputting a measurement instruction, receiving the measurement instruction, and encoding the measurement instruction according to a preset encoding method through an industrial control computer to obtain an encoding result;

[0009] S2. Generating a pressure fluctuation corresponding to the encoding result according to the encoding result through a hole mouth solenoid valve;

[0010] S3. Obtain the pressure fluctuation through the in-hole pressure measurement module, and decode the pressure fluctuation according to a preset decoding method through the CPU module to obtain an operation instruction;

[0011] S4. Operate the drill tool according to the operation instruction, and use the angle measurement module to obtain the attitude angle information corresponding to the drill tool;

[0012] S5. Encode the attitude angle information according to a preset encoding method through the CPU module, and generate the water flow rate fluctuation in the drill pipe corresponding to the attitude angle information according to the encoding result of the attitude angle information through the in-hole solenoid valve;

[0013] S6. Obtain the water flow rate fluctuation in the drill pipe through the orifice flow measurement module;

[0014] S7. Decode the water flow rate fluctuation in the drill pipe according to a preset decoding method through the signal processing module to obtain the original attitude information of the drill tool;

[0015] S8. Solve the original attitude information through the industrial control computer to obtain the real-time trajectory information of the drill tool.

[0016] The beneficial effect of the above solution is: In the present invention, according to the characteristics of the information to be transmitted, a single pressure wave code instruction is designed, which consists of a start bit, a layer bit, a function bit, a data bit, and an end bit. Each bit in the instruction requires adjusting the pressure once for high and low changes, that is, each pressure wave code instruction only needs 5 pressure adjustments to complete. This method greatly reduces the number of pressure adjustments, avoids the time loss during the pressure rising and falling processes, and can significantly reduce the one-way communication duration of the pressure wave code. Combining with streamlining the information quantity of each bit can meet the design requirements of the wave code communication time.

[0017] Further, S4 specifically includes:

[0018] S41. Operate the drill tool according to the operation instruction, and obtain the attitude estimated value of the drill tool;

[0019] S42. Use the angle measurement module to obtain the initial attitude angle information, and update the attitude estimated value according to the initial attitude angle information to obtain the updated initial attitude angle information;

[0020] S43. Further correct the updated initial attitude angle information using the ESKF iterative process formula to obtain the attitude angle information.

[0021] Further, in S1, the measurement instructions include an instruction to read the inclination angle, an instruction to read the azimuth angle, an instruction to read the working face angle, an instruction to read the voltage, and an instruction to read the temperature;

[0022] The encoding result of the preset encoding method includes a start bit, a layer bit, a function bit, a data bit, and an end bit;

[0023] The start bit is used to indicate the start of the pressure wave code instruction;

[0024] The layer bit is used to indicate the layer number of the processing receiver for the pressure wave code instruction;

[0025] The function bit is used to indicate the type of measurement instruction;

[0026] The data bit is used to indicate the data information sent by the pressure wave code instruction;

[0027] The end bit is used to indicate the end of the pressure wave code instruction.

[0028] Furthermore, in the encoding result of the preset encoding method, the pressure levels of adjacent bits are different.

[0029] Furthermore, the wave code duration of the start bit and the end bit is 4 minutes;

[0030] The processing receivers corresponding to the layer bit include a first-layer processing receiver, a second-layer processing receiver, a third-layer processing receiver, and a fourth-layer processing receiver;

[0031] The wave code duration corresponding to the first-layer processing receiver is 2 minutes, the wave code duration corresponding to the second-layer processing receiver is 3 minutes, the wave code duration corresponding to the third-layer processing receiver is 4 minutes, and the wave code duration corresponding to the fourth-layer processing receiver is 5 minutes;

[0032] When the function bit indicates that the measurement instruction is a tilt angle reading instruction, the wave code duration of the function bit is 1 minute; when the function bit indicates that the measurement instruction is an azimuth angle reading instruction, the wave code duration of the function bit is 2 minutes; when the function bit indicates that the measurement instruction is a working face angle reading instruction, the wave code duration of the function bit is 3 minutes; when the function bit indicates that the measurement instruction is a voltage reading instruction, the wave code duration of the function bit is 4 minutes; when the function bit indicates that the measurement instruction is a temperature reading instruction, the wave code duration of the function bit is 5 minutes;

[0033] And the function bit is positively correlated with the magnitude of the base value;

[0034] The magnitude of the data bit is equal to the sum of the base value and the representative value corresponding to the wave code duration of the data bit.

[0035] In a second aspect, a wave code wireless measurement-while-drilling system is implemented based on the wave code wireless measurement-while-drilling method according to any one of claims 1-5, and includes a hole mouth device and a downhole device;

[0036] The hole mouth device includes a hole mouth power supply module, a hole mouth pressure measurement module, a hole mouth flow measurement module, a hole mouth solenoid valve, a signal processing module, an industrial control computer and a display module, and a water flow access module;

[0037] The downhole device includes a battery pack, a downhole power module, a downhole pressure measurement module, a temperature measurement module, a downhole solenoid valve, a CPU module, and an angle measurement module;

[0038] Among them, the wellhead device and the downhole device are connected by a drill pipe.

[0039] Furthermore, the angle measurement module includes a magnetometer module, an accelerometer module, a data processing unit, and a calibration device. Description of the Drawings

[0040] Figure 1 It is a schematic flow diagram of a wave code wireless measurement - while - drilling method.

[0041] Figure 2 It is a schematic composition diagram of a wave code wireless measurement - while - drilling system.

[0042] Figure 3 It is a schematic diagram of the instruction format.

[0043] Figure 4 It is a schematic diagram of the instruction duration. Detailed Embodiments

[0044] The present invention will be further described below with reference to the drawings and specific embodiments.

[0045] Embodiment 1

[0046] As Figure 1 shown, a wave code wireless measurement - while - drilling method, applied to a wave code wireless measurement - while - drilling system, includes:

[0047] S1. In response to an operator inputting a measurement instruction, receive the measurement instruction, and encode the measurement instruction according to a preset encoding method through an industrial control computer to obtain an encoding result.

[0048] In this embodiment, in S1, the measurement instructions include an instruction to read the inclination angle, an instruction to read the azimuth angle, an instruction to read the working face angle, an instruction to read the voltage, and an instruction to read the temperature;

[0049] The encoding result of the preset encoding method includes a start bit, a layer bit, a function bit, a data bit, and an end bit;

[0050] The start bit is used to represent the start of the pressure wave code instruction;

[0051] The layer bit is used to represent the number of layers of the processing receiver of the pressure wave code instruction;

[0052] The function bit is used to represent the type of the measurement instruction;

[0053] The data bit is used to represent the data information sent down by the pressure wave code instruction;

[0054] The end bit is used to represent the end of the pressure wave code instruction.

[0055] In this embodiment, in the encoding result of the preset encoding method, the pressure levels of adjacent bits are different.

[0056] In this embodiment, the wave code duration of the start bit and the end bit is 4 minutes;

[0057] The processing receivers corresponding to the layer bits include a first-layer processing receiver, a second-layer processing receiver, a third-layer processing receiver, and a fourth-layer processing receiver;

[0058] The wave code duration corresponding to the first-layer processing receiver is 2 minutes, the wave code duration corresponding to the second-layer processing receiver is 3 minutes, the wave code duration corresponding to the third-layer processing receiver is 4 minutes, and the wave code duration corresponding to the fourth-layer processing receiver is 5 minutes;

[0059] When the function bit represents that the measurement instruction is a tilt angle reading instruction, the wave code duration of the function bit is 1 minute; when the function bit represents that the measurement instruction is an azimuth angle reading instruction, the wave code duration of the function bit is 2 minutes; when the function bit represents that the measurement instruction is a working face angle reading instruction, the wave code duration of the function bit is 3 minutes; when the function bit represents that the measurement instruction is a voltage reading instruction, the wave code duration of the function bit is 4 minutes; when the function bit represents that the measurement instruction is a temperature reading instruction, the wave code duration of the function bit is 5 minutes;

[0060] And the function bit is positively correlated with the magnitude of the base value;

[0061] The magnitude of the data bit is equal to the sum of the base value and the representative value corresponding to the wave code duration of the data bit.

[0062] In a specific embodiment, the duration of each data bit occupies 3 minutes, a single instruction is 4 bytes, plus 1 start bit and 1 stop bit, and the duration of the instruction needs to reach ((8bit × 4) + 1bit + 1bit) × (3min / bit) = 102min. According to the working conditions, it is necessary to reasonably formulate the encoding rules to shorten the information sequence so that the unidirectional communication time of the pressure wave code ≤ 35min.

[0063] According to the characteristics of the information to be transmitted, a single pressure wave code instruction is designed, which consists of a start bit, a layer bit, a function bit, a data bit, and an end bit. Each bit in the instruction needs to adjust the pressure level once, that is, each pressure wave code instruction only needs 5 pressure adjustments to complete. This method greatly reduces the number of pressure adjustments, avoids the time loss during the pressure rise and fall processes, and can significantly reduce the unidirectional communication duration of the pressure wave code. Combining with streamlining the information quantity of each bit, the design requirements for the wave code communication time can be met.

[0064] As shown in Table 1, Table 1 is the wave code instruction database in this embodiment.

[0065] Table 1 Wave Code Instruction Database

[0066]

[0067] As Figure 3 and Figure 4 shown, Figure 3 is a schematic diagram of the instruction format, Figure 4 is a schematic diagram of the instruction duration. A single wave code instruction consists of a start bit code + layer bit code + function code + data code + end code. The start bit code represents the start of the pressure wave code instruction; the layer bit code is used to indicate which layer's receiver receives and executes this wave code command; the function code is used to represent the current command, including reading the tilt angle, azimuth angle, working face angle, voltage, and temperature; the data code is the data information that this instruction needs to send; the end code represents the end of the instruction.

[0068] Based on Figure 4 it, the specific description is as follows:

[0069] a) Start bit: The wave code duration of the start bit of wave code propagation is fixed at 4 min.

[0070] b) Layer: There are four values, representing the receivers of the first to fourth layers respectively, and the corresponding wave code durations are 2 min, 3 min, 4 min, and 5 min.

[0071] c) Function bit: The function bit represents the function or data bit description of this instruction. Among them, the functions are divided into reading the tilt angle, azimuth angle, working face angle, voltage, and temperature functions, corresponding to wave code durations of 1 min, 2 min, 3 min, 4 min, and 5 min respectively. The function bit describes the base value of the data bit, with an increment value of 24 s. Every time 24 s is increased, the base value is increased by 100. The corresponding relationship between the function bit duration and the base value is shown in Table 2, and Table 2 is the corresponding relationship between the function bit duration and the base value;

[0072] Table 2 is the corresponding relationship between the function bit duration and the base value

[0073] Serial number Function bit duration Data bit base value 1 5 min + 24 s 0 2 5 min + 48 s 100 3 5 min + 72 s 200 4 5 min + 96 s 300 5 5 min + 120 s 400 6 5 min + 144 s 500 7 5 min + 168 s 600 8 5 min + 192 s 700 9 5 min + 216 s 800 10 5 min + 240 s 900

[0074] d) Data bit: The duration of the wave code propagation data bit is 6 s to 600 s, with an increment value of 6 s. Every time 6 s is increased, the value represented by the data bit is increased by 1. When the data bit duration is 6 s, the represented value is 0; when the data bit duration is 12 s, the represented value is 1; and so on. When the data bit duration is 594 s, the represented value is 98; when the data bit duration is 600 s, the represented value is 99. After calculating the value of the data bit, adding the base value calculated from the function bit is the value to be transmitted. For example, if the function bit duration is 5 min + 240 s and the data bit duration is 12 s, the transmitted value is 900 + 1 = 901.

[0075] In summary, accumulate the maximum duration of each bit: 4 min + 5 min + 9 min + 10 min + 4 min = 32 min. The maximum duration of the wave code command is 32 min.

[0076] Optionally, the preset decoding method can be the decoding method corresponding to the preset encoding method, or other decoding methods can be used. There is no specific limitation on the decoding method here.

[0077] e) End bit: The duration of the wave code propagation end bit is fixed at 4 min.

[0078] S2. Generate a pressure fluctuation corresponding to the encoding result through the orifice solenoid valve according to the encoding result.

[0079] S3. Obtain the pressure fluctuation through the in-hole pressure measurement module, and decode the pressure fluctuation according to the preset decoding method through the CPU module to obtain an operation instruction.

[0080] S4. Operate the drill tool according to the operation instruction, and obtain the attitude angle information corresponding to the drill tool using the angle measurement module.

[0081] In this embodiment, S4 specifically includes:

[0082] S41. Operate the drill tool according to the operation instruction, and obtain the attitude estimation value of the drill tool;

[0083] S42. Obtain the initial attitude angle information using the angle measurement module, and update the attitude estimation value according to the initial attitude angle information to obtain the updated initial attitude angle information;

[0084] S43. Further correct the updated initial attitude angle information using the ESKF iterative process formula to obtain the attitude angle information.

[0085] In this embodiment, in S42, the calculation formula that can be used to obtain the attitude estimation value of the drill tool is: Prediction (prior) state estimation: Prediction (prior) estimation covariance:

[0086] The steps of obtaining the initial attitude angle information using the angle measurement module and updating the attitude estimation value according to the initial attitude angle information can be:

[0087] Innovation or measurement residual:

[0088] Innovation (or residual) covariance:

[0089] Optimal Kalman gain:

[0090] Updated (posterior) state estimate:

[0091] Updated (posterior) covariance: P K|K =(I - K k H k )P K|K-1 ;

[0092] In S43, the ESKF iteration process may include:

[0093] 1) Updating the global attitude estimate

[0094] According to the definition of quaternion differentiation:

[0095]

[0096] And a constraint

[0097] The differential equation of the quaternion can be derived, also known as the motion equation of the quaternion:

[0098]

[0099] where q is the current true attitude of the device, w is the current true angular velocity of the device.

[0100] Since it is an estimate of the current attitude of the device, therefore, the motion equation of the quaternion can be written as:

[0101]

[0102] where the symbol ∧ represents the estimate.

[0103] And the estimated angular velocity and the measured angular velocity w out The relationship between them is:

[0104]

[0105] where, is the estimated gyro bias.

[0106] According to the first-order approximation equation obtained from the differential equation: After integration, we can get: q(t + Δt) - q(t) = ΔqΔt. Therefore, q(t + Δt) = ΔqΔt + q(t). The new attitude q(t + Δt) at time t + Δt is approximately the superposition of the old attitude q(t) at time t and the attitude change ΔqΔt.

[0107] 2) Establishment of the prediction equation

[0108] Assume that the current true attitude of the body is q, and the attitude estimated using the above approximate equation is The error between the two is δq. Their relationship can be expressed as: where, represents the JPL-convention quaternion multiplication. Since the error quaternion δq is very small and far from the singularity, it can be converted into a 3D vector a for representation, also known as the rotation error vector. Generally, the Gibbs vector is chosen for representation, denoted by the symbol ag. The relationship between the two is: Because the error is very small, the norm is also very small. Therefore, for simplicity of calculation, it can be second-order approximated as: For the variation laws of the rotation error vector a and the gyro bias b, there is a state vector x which can be calculated as: The state vector needs to be estimated using a Kalman filter.

[0109] The key task in applying the Kalman filter is to establish the state propagation matrix, which describes how the state changes from one step to the next: X t +D t = fX t . For a non-linear problem, the matrix F is obtained by linearizing the local derivatives. First, an expression for is obtained. The matrix J is called the system dynamics matrix. Then the state transition matrix F = EXP(Jdt). Expanding the exponential and ignoring the higher-order terms, we can get: F = I + Jdt. Therefore, the task is simplified to finding the matrix J. To obtain the dynamics matrix of the rotation error vector a, its differential equation needs to be solved. Expanding the differential equation and arranging the terms, we get Therefore, we can obtain where, is a 3×3 skew-symmetric matrix: (t + 1) = Fx(t),

[0110] Since ESKF requires resetting before each loop iteration, that is, after executing is already the optimal estimate of q. At this time, Therefore, a(t) = 0 before the start of each iteration. In the ideal state, is already the optimal estimate of q. At this time, and the gyro bias b does not change either. Only when a correction operation (measurement update) occurs will the error and bias change.

[0111] ​For ESKF, the prediction (prior) state estimation does not require calculation. The purpose of calculating the state propagation matrix F is to calculate the covariance P. Obtain the prediction (prior) estimation covariance P. The process noise covariance Q matrix required for calculating the prior estimation covariance matrix P is the discrete-time system noise covariance matrix Qd. The continuous-time system noise covariance matrix is given as: where is the gyroscope variance, a 3×3 diagonal matrix, is the gyroscope bias covariance matrix, also a 3×3 diagonal matrix. Then the discrete-time system noise covariance matrix Qd can be calculated as: where,

[0112] Optionally, if higher accuracy is required, calculate the higher-order formula. Since and Δt are both very small, if the calculation is to be simplified to improve speed, the high-power product of the two can be ignored, and the process noise covariance can also be simplified to:

[0113] 3) Update equation

[0114] In the measurement update stage, the goal is to find the observation matrix H of the system. Using the fixed vector observation method, the gravity vector pointing to the center of the earth and the geomagnetic vector pointing to the magnetic pole are observed respectively, thus correcting the errors and biases.

[0115] 3.1 Acceleration correction

[0116] Acceleration correction means regarding the gravity vector g = [0 0 g] in the world coordinate system as a fixed vector for observation. Using to represent the rotation from the body coordinate system to the world coordinate system, so will represent the transformation from the world coordinate system to the body coordinate system, so In the rotated body coordinate system, the measured vector gmeas measured by the accelerometer contains the linear acceleration caused by external forces. Assuming that the external forces are variable and have zero mean over a period of time. Using the global attitude quaternion inverse to rotate the gravity vector g in the inertial coordinate system to the attitude that coincides with the body coordinate system, and then subtracting it from the measured vector gmeas to obtain the residual:

[0117] Since is represented as the rotation matrix as Therefore, the Ha matrix measured by the accelerometer obtained from the above formula is: So the observation matrix H of the system at this time is: H = [H a 03*3 .

[0118] In addition, the measurement noise covariance matrix R: where, is the 3×3 measurement variance of the accelerometer.

[0119] By calculating the Kalman gain K, a new error vector is obtained, and then the global attitude quaternion is corrected with partial data, which corrects Roll&Pitch in the Euler angles. Then the system is reset.

[0120] 3.2 Geomagnetic correction

[0121] For geomagnetic correction, the geomagnetic vector m = [0 m 0] in the world coordinate system is regarded as a fixed vector for observation. The specific value in the y-axis direction is not very important. The key is that there is data in the y-axis direction while the data in the x-axis and z-axis are 0. When the vector value in a certain direction is disturbed, it is reflected in the Kalman gain matrix K. Therefore, the geomagnetic vector can be temporarily set simply as m = [0 1 0], and then the residual is obtained by subtracting it from the measurement vector mmeas: Since is represented as a rotation matrix as The Ha matrix measured by the accelerometer obtained from the above formula is:

[0122] The observation matrix H of the system is: H = [H a 0 3*3 . The measurement noise covariance matrix R can be calculated as: where, is the 3×3 measurement variance of the magnetometer.

[0123] By calculating the Kalman gain k, a new error vector is obtained, and then the global attitude quaternion is corrected with partial data to correct Yaw in the Euler angles. Finally, the system is reset to complete one iteration.

[0124] S5. The CPU module encodes the attitude angle information according to a preset encoding method, and the in-hole solenoid valve generates the flow rate fluctuation of the water flow in the drill pipe corresponding to the attitude angle information according to the encoding result of the attitude angle information.

[0125] S6. The in-hole flow rate measurement module obtains the flow rate fluctuation of the water flow in the drill pipe.

[0126] S7. The signal processing module decodes the flow rate fluctuation of the water flow in the drill pipe according to a preset decoding method to obtain the original attitude information of the drill tool.

[0127] S8. Solve the original attitude information through the industrial control computer to obtain the real-time trajectory information of the drill string.

[0128] Exemplarily, to obtain the real-time trajectory information of the drill string, data such as the real-time trajectory information and temperature can be displayed on the display screen of the industrial control computer.

[0129] Embodiment 2

[0130] As Figure 2 shown, a wave code wireless measurement-while-drilling system, implemented based on the wave code wireless measurement-while-drilling method, includes a hole mouth device and a downhole device;

[0131] The hole mouth device includes a hole mouth power module, a hole mouth pressure measurement module, a hole mouth flow measurement module, a hole mouth solenoid valve, a signal processing module, an industrial control computer, a display module, and a water flow access module;

[0132] The downhole device includes a battery pack, a downhole power module, a downhole pressure measurement module, a temperature measurement module, a downhole solenoid valve, a CPU module, and an angle measurement module;

[0133] Among them, the hole mouth device and the downhole device are connected by drill pipes.

[0134] Exemplarily, the hole mouth pressure measurement module and the hole mouth flow measurement module form a signal receiving device, which is responsible for completing signal reception and decoding. Specifically,

[0135] The hole mouth pressure measurement module and the hole mouth flow measurement module are installed at the drill pipe inlet, detect the pressure and flow changes of the fluid in the drill pipe, and convert them into digital signals through an ADC and an MCU.

[0136] Due to the complex conditions inside the drill pipe, the signal transmission process will be interfered by many noises, resulting in a small signal amplitude and large noise received by the hole mouth device. Through the signal processing module, the noise is filtered and the signal is enhanced.

[0137] Convert the processed digital signal into the required downhole engineering parameters through the coding specification, and draw a drilling trajectory diagram based on this data.

[0138] The downhole device in this embodiment is installed inside the drill pipe, enters the borehole along with the drill pipe, measures the attitude angle of the drill pipe, controls the pressure and flow fluctuations of the water flow inside the drill pipe through the downhole solenoid valve, and transmits information such as the attitude angle, temperature, and battery voltage of the drill pipe to the hole mouth device.

[0139] The downhole power module can be used alone to supply power to the device, meeting the continuous operation for a long time (not less than 90 hours). The downhole power module adopts a comprehensive judgment management system power supply for vibration monitoring and pressure monitoring, automatically supplies power and puts the downhole modules into sleep according to needs, controls the power consumption efficiency of the downhole equipment, and reduces power consumption.

[0140] Optionally, the system may further include a vibration detection module and an acceleration detection module, which identify the tooling state of the device through the in-hole pressure measurement module and the in-hole vibration detection module, and based on this, intermittent operation is achieved.

[0141] When the drill rig is drilling, drilling fluid is used to drive the drill rig to work. At this time, the pressure of the drilling fluid is greater than 4 MPa, and at the same time, the vibration generated by the drill bit drilling has an amplitude greater than 1.5 g. Therefore, when the in-hole pressure detection module and the acceleration detection module detect that the pressure is greater than the threshold and the vibration is greater than the threshold, the working state of the device is in the drilling mode.

[0142] When the drill rig stops drilling, the pressure of the drilling fluid decreases and the vibration amplitude decreases; therefore, when the pressure detection module and the acceleration detection module detect that the pressure is less than the threshold and the vibration is less than the threshold, the working state of the device is in the stop mode.

[0143] When the working state is in the drilling mode, the in-hole device is in the sleep state to save power consumption.

[0144] When the working state is in the stop mode, the data acquisition module is started to collect static parameters such as the inclination angle, azimuth angle, and tool face angle of the drilling trajectory; and the data transceiver unit is started to send the inclination angle, azimuth angle, and tool face angle. After the data is sent, the device enters the sleep state and waits for the next working state mode switching operation.

[0145] In this embodiment, the angle measurement module includes a magnetometer module, an accelerometer module, a data processing unit, and a calibration device. Exemplarily, in the measurement while drilling in a coal mine, the orifice device in this embodiment is installed between the orifice drill pipe and the water pump. The pressure and flow rate measurement module detects the fluctuation signals of the pressure and flow rate, and the collected fluctuation signals enter the signal processing module to analyze the attitude angle and other signals transmitted from the in-hole device. The attitude angle signal is combined with the recorded drill pipe entry hole stroke to calculate the drilling trajectory, and the trajectory is displayed on the industrial control computer screen. The magnetometer module is used to measure the three-dimensional vector of the earth's magnetic field. The accelerometer module is used to measure the three-dimensional components of the object's acceleration. The data processing unit is used to receive sensor data, perform data fusion and attitude angle calculation. The calibration device is used to calibrate the sensor to ensure the accuracy of the measurement data.

[0146] When the device starts to work, the system is initialized, and self-check and calibration of the sensors are performed. The magnetometer module and the accelerometer module collect environmental magnetic field and acceleration data in real time. The data processing unit uses the Kalman filter or other fusion algorithms to combine the data of the magnetometer module and the accelerometer module to calculate the real-time attitude angle of the drill pipe. The calculated attitude angle is output to the control system or other devices through the communication interface. The control system performs feedback adjustment according to the attitude angle information to maintain or adjust the object to the desired attitude.

[0147] Those of ordinary skill in the art will realize that the embodiments described herein are provided to assist the reader in understanding the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific deformations and combinations that do not depart from the essence of the present invention based on these technical revelations disclosed in the present invention, and these deformations and combinations are still within the scope of protection of the invention.

Claims

1. A wave code wireless measurement while drilling method, applied to a wave code wireless measurement while drilling system, characterized in that: The method comprises: S1, in response to an operator inputting a measurement instruction, receiving the measurement instruction, encoding the measurement instruction according to a preset encoding method through an industrial computer, and obtaining an encoding result; S2. generating a pressure fluctuation corresponding to the coding result according to the coding result through an orifice solenoid valve; S3, obtaining the pressure fluctuation through the in-hole pressure measurement module, and decoding the pressure fluctuation through the CPU module according to a preset decoding method to obtain an operation instruction; S4, operating the drilling tool according to the operation instruction, and using the angle measurement module to obtain the attitude angle information corresponding to the drilling tool; S5, encoding the attitude angle information according to a preset encoding method through the CPU module, and generating water flow fluctuation in the drill pipe corresponding to the attitude angle information according to the encoding result of the attitude angle information through the solenoid valve in the hole; S6, obtaining the water flow fluctuation in the drill pipe through the orifice flow measurement module; S7, decoding the water flow fluctuation in the drill pipe according to a preset decoding method through a signal processing module to obtain original posture information of the drilling tool; S8. Solve the original posture information by the industrial computer to obtain the real-time trajectory information of the drilling tool.

2. The method according to claim 1, characterized in that The S4 specifically includes: S41, operating the drilling tool according to the operation instruction, and obtaining an estimated value of the posture of the drilling tool; S42, using the angle measurement module to obtain initial attitude angle information, and updating the attitude estimation value according to the initial attitude angle information to obtain updated initial attitude angle information; S43, using the ESKF iterative process formula to further correct the updated initial attitude angle information to obtain the attitude angle information.

3. The method according to claim 2, characterized in that In S1, the measurement instructions include an instruction to read the inclination angle, an instruction to read the azimuth angle, an instruction to read the working surface angle, an instruction to read the voltage, and an instruction to read the temperature; The encoding result of the preset encoding method includes a start bit, a layer bit, a function bit, a data bit and an end bit; The start bit is used to indicate the beginning of the pressure wave code instruction; The layer is used to represent the layer number of the processing receiver of the pressure wave code instruction; The function bit is used to characterize the type of measurement instruction; The data bit is used to represent the data information sent by the pressure wave code instruction; The end bit is used to indicate the end of the pressure wave code instruction.

4. The method according to claim 3, characterized in that In the encoding result of the preset encoding method, adjacent bits have different pressure levels.

5. The method according to claim 4, characterized in that The wave code duration of the start bit and the end bit is 4 minutes; The processing receivers corresponding to the layers include a first layer processing receiver, a second layer processing receiver, a third layer processing receiver and a fourth layer processing receiver; The wave code duration corresponding to the first layer processing receiver is 2 minutes, the wave code duration corresponding to the second layer processing receiver is 3 minutes, the wave code duration corresponding to the third layer processing receiver is 4 minutes, and the wave code duration corresponding to the fourth layer processing receiver is 5 minutes; When the function bit characterization measurement instruction is a tilt angle reading instruction, the wave code duration of the function bit is 1 minute; when the function bit characterization measurement instruction is a azimuth angle reading instruction, the wave code duration of the function bit is 2 minutes; when the function bit characterization measurement instruction is a working surface angle reading instruction, the wave code duration of the function bit is 3 minutes; when the function bit characterization measurement instruction is a voltage reading instruction, the wave code duration of the function bit is 4 minutes; when the function bit characterization measurement instruction is a temperature reading instruction, the wave code duration of the function bit is 5 minutes; And the function bit is positively correlated with the base value; The size of the data bit is equal to the sum of the base value and the representative value corresponding to the wave code duration of the data bit.

6. A wave code wireless measurement while drilling system, implemented based on the wave code wireless measurement while drilling method according to any one of claims 1 to 5, characterized in that: It includes orifice devices and in-hole devices; The orifice device includes an orifice power module, an orifice pressure measurement module, an orifice flow measurement module, an orifice solenoid valve, a signal processing module, an industrial computer, a display module and a water flow access module; The in-hole device includes a battery pack, an in-hole power module, an in-hole pressure measurement module, a temperature measurement module, an in-hole solenoid valve, a CPU module and an angle measurement module; Wherein, the orifice device and the in-hole device are connected via a drill rod.

7. The system according to claim 6, characterized in that The angle measurement module includes a magnetometer module, an accelerometer module, a data processing unit and a calibration device.

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