A rotary drilling rig dual mode drilling switching control method and system

Abstract

The application discloses a rotary drilling rig double-mode drilling switching control method and system, and relates to the field of drilling equipment control. The method comprises the following steps: modeling drilling mode switching by using a finite state machine; acquiring torque and footage speed parameters in real time; entering a pre-judgment state when torque is greater than a first threshold value and speed is less than a first threshold value in a standby state; entering a confirmation state when a fluctuation rate is less than a fluctuation threshold value for more than a first time in the pre-judgment state; entering a switching transition state when the product of torque and speed is more than a coupling threshold value for more than a second time in the confirmation state; switching to a down-the-hole hammer impact mode after the rotating speed is reduced to below a low-speed threshold value in the switching transition state; entering a back-switching judgment state when torque is less than a second threshold value and speed is greater than a second threshold value in an impact operation state, and switching back to a soil rotary drilling mode after a delay confirmation. The application has the beneficial effects that it realizes automatic, accurate and safe switching of drilling modes, avoids misjudgment and damage to equipment caused by switching under load.

Description

Technical Field

[0001] This invention relates to the field of drilling equipment control technology, specifically a dual-mode drilling switching control method and system for rotary drilling rigs. Background Technology

[0002] Rotary drilling rigs are widely used in pile foundation construction. For drilling operations in complex strata, especially hard rock strata, a combination of rotary drilling and down-the-hole hammer percussion drilling is usually used. In existing technologies, switching between the two drilling modes mainly relies on the operator's experience and judgment, and the mode switch is manually executed after observing the drilling status. Some automated solutions use a single parameter threshold to trigger the switching, such as directly outputting the switching command based solely on torque or solely on the comparison of the drilling speed with a set threshold.

[0003] However, manual judgment methods suffer from strong subjectivity and slow response, making them difficult to adapt to rapid changes in formation conditions. Single-parameter threshold triggering methods are susceptible to instantaneous spikes and cannot distinguish between hard rock formations and stuck drill conditions, leading to frequent erroneous switching. Furthermore, existing solutions typically execute the switching action directly during mode switching, lacking transition control, and switching under load can easily damage the power switching device. At the same time, existing solutions lack state interlocking and back-cut confirmation mechanisms after switching, which can easily lead to frequent switching and state disorder at the interface between soft and hard formations, seriously affecting construction safety and equipment reliability.

[0004] Therefore, there is an urgent need for a dual-mode drilling switching control method and system for rotary drilling rigs to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a dual-mode drilling switching control method and system for rotary drilling rigs, which realizes automatic, accurate and safe switching of drilling modes, avoiding misjudgment and damage to equipment during switching under load.

[0006] To achieve the above objectives, the present invention employs the following technical solution: On one hand, this invention provides a dual-mode drilling switching control method for rotary drilling rigs, employing a finite state machine to model and control the drilling mode switching process. The finite state machine includes a standby state, a prediction state, a confirmation state, a switching transition state, an impact operation state, and a back-cut determination state. The method includes: S1. Real-time acquisition of the driving torque parameters and advance speed parameters of the rotary drilling component; S2. In standby mode, when the driving torque parameter is greater than the first torque threshold and the advance speed parameter is less than the first speed threshold, the system enters the pre-judgment state. S3. In the prediction state, when the comparison result in S2 is held continuously for a longer time than the first time threshold and the fluctuation rate of the driving torque parameter is less than the fluctuation threshold, the system enters the confirmation state. S4. In the confirmed state, when the product of the driving torque parameter and the advance speed parameter continues to exceed the coupling threshold and exceeds the second time threshold, the system enters the switching transition state. S5. In the transition state, after controlling the rotation speed of the rotary drilling component to drop below the low speed threshold according to the preset slope, output the mode switching command to switch the drilling mode from soil rotary drilling mode to down-the-hole hammer impact drilling mode and enter the impact operation state. S6. In the impact operation state, when the driving torque parameter is less than the second torque threshold and the advance speed parameter is greater than the second speed threshold, the system enters the back-cut determination state. In the back-cut determination state, when the above state continues to exceed the third time threshold, the system controls the drilling mode to switch back to the soil rotary drilling mode and returns to the standby state.

[0007] Preferably, in step S1, the driving torque parameter is obtained by acquiring the three-phase current signal of the rotary drilling component's drive motor and performing coordinate transformation. Axis current components, and according to The relationship between shaft current components and torque is obtained through conversion. The advance speed parameter is obtained by collecting pulse signals from a displacement sensor or encoder and then processing them through a moving average filter.

[0008] Preferably, in step S3, the fluctuation rate of the driving torque parameter is determined in the following manner: During the predicted duration, drive torque parameters are collected at a fixed sampling period to obtain the results from... Torque sequence composed of sample values Calculate the mean of the torque sequence. and standard deviation Standard deviation with the mean The ratio is used as volatility; When the volatility is less than the volatility threshold, the torque is determined to be in a stable high-load state, and entry into the confirmation state is allowed; When the volatility is greater than or equal to the volatility threshold, the torque is determined to be in an unstable state, and the system returns to the standby state and resets the prediction state's advance time.

[0009] Preferably, in step S4, the determination that the product of the driving torque parameter and the advance speed parameter continuously exceeds the coupling threshold and exceeds the second time threshold is made using a sliding window determination method: During the duration of the confirmation state, drive torque parameters are synchronously acquired at a fixed sampling period. and advance speed parameters Calculate the coupling parameters at each sampling time. ; With length as The sliding window iterates through the sequence of coupling parameters. When all coupling parameters in the sliding window are within the sequence... When all values ​​are greater than the coupling threshold and the duration of the sliding window reaches the second time threshold, it is determined to be a hard rock formation and enters a switching transition state; When any coupling parameter appears in the sliding window If the value is less than or equal to the coupling threshold, clear the confirmation state timer and restart counting.

[0010] Preferably, in step S4, the coupling threshold is determined in the following manner: In the rotary drilling mode of soil layer, the driving torque parameters and advance speed parameters of historical working conditions are collected at a fixed sampling period. The torque-speed product at each sampling time is calculated, and the statistical upper quantile value of the torque-speed product under normal soil layer drilling conditions is taken as the coupling threshold. The statistical quantile values ​​are the 90th to 95th percentile values.

[0011] Preferably, in step S5, the rotational speed of the rotary drilling component is reduced to below a low-speed threshold by a preset slope, employing a slope reduction control logic, including: Decrease by preset speed step size and control cycle Each control cycle decreases the speed command value by one step until the current speed is lower than the low speed threshold. During the speed reduction process, the drive torque parameter is monitored in real time. If the drive torque parameter exceeds the limit torque threshold, the reduction is paused and the current speed command value is kept unchanged until the drive torque parameter recovers to below the limit torque threshold and then the reduction continues. If the driving torque parameter exceeds the limit torque threshold for a period of time exceeding the fourth time threshold during the speed reduction process, it is determined to be a switching abnormality, the mode switching is terminated and the system returns to standby state, and an abnormal alarm command is output.

[0012] Preferably, in the impact operation mode, the air supply pressure parameter of the down-the-hole hammer is acquired in real time. When the air supply pressure parameter is lower than the minimum pressure threshold, the impact operation mode is forcibly exited and the machine returns to the standby mode, while a shutdown protection command is output. When the gas supply pressure parameter is lower than the minimum pressure threshold and the duration exceeds the fifth time threshold, an emergency shutdown command is output.

[0013] Preferably, the finite state machine is provided with state interlocking logic, specifically as follows: Only a one-way state transition is allowed: standby state → prediction state → confirmation state → switching transition state → impact operation state → back-cut judgment state → standby state; If the judgment condition in any state is not met and the duration exceeds the reset time threshold, the system will be forced to return to the standby state and the timer and intermediate variables of that state will be reset. In the impact operation state, it is only allowed to return to the standby state through the back-cut judgment state, and it is prohibited to jump directly from the impact operation state to the prediction state or the confirmation state. If the speed is not reduced to below the low speed threshold during the transition state, it is prohibited to enter the impact operation state. In the cutback determination state, if the driving torque parameter recovers to a value greater than the first torque threshold or the advance speed parameter recovers to a value less than the first speed threshold, it is determined that the formation has not completed the switching, and the system is forced to return to the impact operation state and reset the cutback determination state timer.

[0014] On the other hand, the present invention also provides a dual-mode drilling switching control system for rotary drilling rigs, for implementing the method described above, including: The parameter acquisition module is used to acquire the driving torque parameters and advance speed parameters of the rotary drilling component in real time. The state machine control module stores a finite state machine model, which includes a standby state, a prediction state, a confirmation state, a switching transition state, an impact operation state, and a back-cut determination state. The state machine control module controls the state switching according to the output of the parameter acquisition module and the state transition conditions. The mode switching output module is used to output a mode switching command when entering the switching transition state; The storage module is used to store various threshold parameters.

[0015] Preferably, the state machine control module includes a prediction determination unit, a coupling determination unit, a transition control unit, and a back-cut determination unit; The prediction and determination unit is used to enter the prediction state when the driving torque parameter is greater than the first torque threshold and the advance speed parameter is less than the first speed threshold in the standby state. In the prediction state, the driving torque parameter is collected at a fixed sampling period, and the ratio of the mean to the standard deviation of the torque sequence is calculated as the volatility. When the volatility is less than the volatility threshold and the duration exceeds the first time threshold, a confirmation trigger signal is output. When the volatility is greater than or equal to the volatility threshold, the unit returns to the standby state and resets the prediction state timer. The coupling determination unit is used to synchronously collect drive torque parameters and advance speed parameters at a fixed sampling period in the confirmation state, calculate the product of the two as the coupling parameter, and traverse the coupling parameter sequence with a sliding window. When all coupling parameters in the sliding window are greater than the coupling threshold and the duration reaches the second time threshold, a switching trigger signal is output. When a coupling parameter in the sliding window is less than or equal to the coupling threshold, the confirmation state timer is cleared. The transition control unit is used to decrease the speed command value according to a preset speed decrease step size and control cycle in the switching transition state, and to stop decreasing and maintain the current speed when the driving torque parameter exceeds the limit torque threshold, until the speed drops below the low speed threshold and then outputs the mode switching command. If the torque continues to exceed the limit and exceeds the fourth time threshold, the switching is determined to be abnormal and the unit returns to the standby state. The back-cut determination unit is used to enter the back-cut determination state when the driving torque parameter is less than the second torque threshold and the advance speed parameter is greater than the second speed threshold under the impact operation state, and outputs the back-cut command after the duration exceeds the third time threshold. If the torque or speed recovers during the period, it will be forced to return to the impact operation state and the timer will be reset.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention uses a finite state machine to model and control the drilling mode switching process. Through a multi-level progressive state design of standby state, prediction state, confirmation state, switching transition state, impact operation state and back-cut judgment state, the automatic switching of drilling mode is realized, replacing the traditional method that relies on manual experience judgment, significantly reducing the influence of the operator's subjective judgment, and improving the response speed and consistency of mode switching.

[0017] 2. This invention introduces the fluctuation rate determination of the driving torque parameter in the prediction state and adopts the coupled determination of the product of the driving torque parameter and the advance speed parameter in the confirmation state. This effectively avoids misjudgment caused by instantaneous spike interference and can distinguish between hard rock formations and stuck drill conditions, thus improving the accuracy of hard rock formation identification.

[0018] 3. The present invention adopts ramp-down control logic in the transition state. During the speed reduction process, torque monitoring is combined to realize pause reduction and abnormal handling, which avoids damage to the power switching device during load switching and improves the safety of the mode switching process.

[0019] 4. This invention avoids frequent switching and state disorder at the interface between soft and hard strata by using state interlocking logic and back-cut delay confirmation mechanism, thus ensuring the reliability and stability of the control system.

[0020] 5. This invention achieves shutdown protection during impact operation by monitoring the air supply pressure, further improving the safety of down-the-hole hammer operation. Attached Figure Description

[0021] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a schematic diagram of the system structure of the present invention. Detailed Implementation

[0022] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined in this application.

[0023] In this invention, terms such as "upper," "lower," "left," "right," "front," "back," "vertical," "horizontal," "side," and "bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only to facilitate the description of the structural relationships of the various components or elements of this invention and do not specifically refer to any component or element in this invention. They should not be construed as limiting the invention.

[0024] Example: like Figure 1 As shown, this embodiment provides a dual-mode drilling switching control method for rotary drilling rigs, including: The drilling mode switching process is modeled and controlled using a finite state machine. The finite state machine includes at least a standby state, a prediction state, a confirmation state, a switching transition state, an impact operation state, and a return-to-start determination state. The method includes: S1: Real-time acquisition of the driving torque parameters and advance speed parameters of the rotary drilling component; S2: In standby mode, when the driving torque parameter is greater than the first torque threshold and the advance speed parameter is less than the first speed threshold, enter the pre-judgment state; S3: In the prediction state, when the above comparison result is held continuously for a period of time exceeding the first time threshold and the fluctuation rate of the driving torque parameter is less than the fluctuation threshold, the system enters the confirmation state. S4: In the confirmed state, when the product of the driving torque parameter and the advance speed parameter continues to exceed the coupling threshold and exceeds the second time threshold, the system enters the switching transition state. S5: In the transition state, after controlling the rotation speed of the rotary drilling component to drop below the low speed threshold according to the preset slope, output the mode switching command to switch the drilling mode from soil rotary drilling mode to down-the-hole hammer impact drilling mode and enter the impact operation state. S6: In the impact operation state, when the driving torque parameter is less than the second torque threshold and the advance speed parameter is greater than the second speed threshold, the system enters the back-cut determination state; in the back-cut determination state, when the above state continues to exceed the third time threshold, the system controls the drilling mode to switch back to the soil rotary drilling mode and returns to the standby state.

[0025] In this embodiment, the rotary drilling rig is electrically driven. The rotary drilling component is driven by a three-phase asynchronous motor with a rated power of 200kW and a rated voltage of 380V via a reducer. The rated current of the motor is about 360A, the rated torque of the reducer output is 200kN·m, and the rated speed is 22r / min.

[0026] In step S1, the driving torque parameter is obtained by acquiring the three-phase current signal of the rotary drilling component drive motor, and then performing Clarke and Park transformations. Axis current components, and according to The relationship between shaft current components and reducer output torque is obtained through conversion. Specifically, The shaft current component is directly proportional to the output torque of the reducer, with a proportionality coefficient of 0.8 kN·m / A, that is, when... When the shaft current component is 150A, the corresponding reducer output torque is 120kN·m; the feed rate parameter is obtained by collecting displacement pulse signals from a magnetic grating displacement sensor installed on the top of the drill pipe, and then processing them through a moving average filter with a window length of 20 sampling points.

[0027] In this embodiment, the sampling period is set to 50ms, meaning that the drive torque parameter and the advance speed parameter are collected every 50ms. The first torque threshold is set to 120kN·m, corresponding to 60% of the rated torque of the reducer; the first speed threshold is set to 0.05m / min, approximately 1 / 20 of the average advance speed of 1.0m / min during normal soil drilling. This value can reliably distinguish between soft soil drilling and hard rock drilling conditions. In standby mode, when the drive torque parameter is continuously greater than 120kN·m and the advance speed parameter is continuously less than 0.05m / min, the system enters the pre-judgment state.

[0028] In step S3, the fluctuation rate of the driving torque parameter is determined as follows: During the duration of the predicted state, the driving torque parameter is collected at a fixed sampling period of 50ms, resulting in the value obtained from... Torque sequence composed of sample values Calculate the mean of the torque sequence. and standard deviation Standard deviation with the mean The ratio is used as the volatility. In this embodiment, the first time threshold is set to 5 seconds, corresponding to 100 sampling points; the volatility threshold is set to 0.15. When the volatility is less than 0.15, the torque is determined to be in a stable high-load state, allowing entry into the confirmation state; when the volatility is greater than or equal to 0.15, the torque is determined to be in an unstable state, returning to the standby state and resetting the timing of the pre-judgment state. This design can effectively distinguish between stable high loads during hard rock drilling and severe fluctuations during formation interlayers or stuck drill bits, avoiding misjudgments caused by instantaneous spikes.

[0029] In step S4, the determination that the product of the drive torque parameter and the advance speed parameter continuously exceeds the coupling threshold and exceeds the second time threshold is made using a sliding window determination method: during the duration of the confirmation state, the drive torque parameter is synchronously collected at a fixed sampling period of 50ms. and advance speed parameters Calculate the coupling parameters at each sampling time. ; with length as The sliding window iterates through the sequence of coupling parameters. When all coupling parameters in the sliding window are within the sequence... When all parameters exceed the coupling threshold and the duration of the sliding window reaches the second time threshold of 5 seconds, it is determined to be a hard rock formation and enters a switching transition state; when any coupling parameter appears within the sliding window... If the value is less than or equal to the coupling threshold, clear the confirmation state timer and restart counting.

[0030] In this embodiment, the coupling threshold is determined as follows: In the soil rotary drilling mode, historical driving torque and advance speed parameters are collected at a fixed sampling period of 50ms, and the torque-speed product at each sampling moment is calculated. Under normal soil drilling conditions, the driving torque parameter is 30 to 60 kN·m, the advance speed parameter is 0.8 to 1.2 m / min, and the torque-speed product is 24 to 72 kN·m·m / min. The statistical upper quantile of this product under normal soil drilling conditions is taken as the coupling threshold, specifically the 95th percentile, which is statistically calculated to be approximately 70 kN·m·m / min. When drilling enters the hard rock transition stage, the driving torque parameter rises to 130 to 180 kN·m, the drilling speed parameter drops to 0.02 to 0.05 m / min, and the torque-speed product is 2.6 to 9 kN·m·m / min, which is far below the coupling threshold of 70 kN·m·m / min. Therefore, in this embodiment, the triggering condition for coupling determination is modified as follows: when the driving torque parameter is continuously greater than the torque confirmation threshold of 150 kN·m, and the drilling speed parameter is continuously less than the speed confirmation threshold of 0.05 m / min, and the product of the two is continuously less than the lower coupling limit threshold of 10 kN·m·m / min, it is determined to be a hard rock formation and enters the switching transition state.

[0031] In step S5, the process of controlling the rotary drilling component's rotational speed to decrease below the low-speed threshold at a preset slope employs a slope reduction control logic: the rotational speed decreases in preset step sizes. r / min and control cycle In each control cycle, the speed command value is decreased by one step until the current speed is below the low-speed threshold of 8 r / min. In this embodiment, the initial speed is 22 r / min, which decreases to 8 r / min after 7 control cycles (1.4 s). During the speed decrease, the drive torque parameter is monitored in real time. If the drive torque parameter exceeds the limit torque threshold of 190 kN·m (corresponding to 95% of the rated torque of the reducer), the decrease is paused and the current speed command value remains unchanged until the drive torque parameter recovers to below 190 kN·m, after which the decrease continues. If the drive torque parameter exceeds 190 kN·m for more than 3 s during the speed decrease, it is determined to be a switching abnormality, the mode switching is terminated and the system returns to standby state, and an abnormal alarm command is output.

[0032] During impact operation, the air supply pressure parameters of the down-the-hole hammer are acquired in real time. When the air supply pressure parameter is lower than the minimum pressure threshold of 0.5 MPa, the system forcibly exits the impact operation state and returns to the standby state, while simultaneously outputting a shutdown protection command. When the air supply pressure parameter is lower than 0.5 MPa for a duration exceeding the fifth time threshold of 3 seconds, an emergency shutdown command is output. In this embodiment, a medium-pressure down-the-hole hammer is used, and the air supply pressure required for normal operation is 0.7 to 1.4 MPa. The minimum pressure threshold of 0.5 MPa is set to approximately 70% of the lower limit of the normal operating pressure.

[0033] In step S6, the second torque threshold is set to 80 kN·m, which is less than the first torque threshold of 120 kN·m; the second speed threshold is set to 0.3 m / min, which is greater than the first speed threshold of 0.05 m / min, thus forming a hysteresis design. In the impact operation state, when the driving torque parameter is less than 80 kN·m and the advance speed parameter is greater than 0.3 m / min, the system enters the back-cut determination state. In the back-cut determination state, if the above state continues for more than 10 seconds, the drilling mode is switched back to the soil rotary drilling mode and the system returns to the standby state.

[0034] In this embodiment, the finite state machine is equipped with state interlocking logic: only unidirectional state transition is allowed from standby state to prediction state to confirmation state to switching transition state to impact operation state to back-cut determination state and back to standby state, and cross-state jumps are prohibited; when the determination condition in any state is not met and the duration exceeds the reset time threshold of 2s, the system is forced to return to the standby state and the timer and intermediate variables of that state are reset; in the impact operation state, the system is only allowed to return to the standby state through the back-cut determination state, and it is prohibited to jump directly from the impact operation state to the prediction state or confirmation state; in the switching transition state, if the action of reducing the speed to below the low speed threshold is not completed, the system is prohibited from entering the impact operation state; in the back-cut determination state, if the driving torque parameter recovers to a value greater than the first torque threshold of 120kN·m or the advance speed parameter recovers to a value less than the first speed threshold of 0.05m / min, it is determined that the formation has not completed the switching, the system is forced to return to the impact operation state and the timer of the back-cut determination state is reset.

[0035] like Figure 2 As shown, this embodiment also provides a dual-mode drilling switching control system for rotary drilling rigs, including: The parameter acquisition module is used to acquire the driving torque parameters and advance speed parameters of the rotary drilling component in real time. Specifically, it includes a current transformer installed on the three-phase line of the drive motor, a magnetic grating displacement sensor installed on the top of the drill rod, and a pressure sensor installed on the air supply line of the down-the-hole hammer. The output signal of the current transformer is connected to the A / D sampling port of the controller through the signal conditioning circuit. The sampling accuracy is 12 bits and the sampling frequency is 20kHz. The state machine control module is implemented using a Siemens S7-1200 series PLC. It stores a finite state machine model, which includes a standby state, a prediction state, a confirmation state, a transition state, an impact operation state, and a back-cut determination state. The state machine control module controls the state switching according to the state transition conditions described in claim 1 based on the output of the parameter acquisition module. The state machine control module includes a prediction determination unit, a coupling determination unit, a transition control unit, and a back-cut determination unit. The prediction and judgment unit is used to enter the prediction state when the driving torque parameter is greater than the first torque threshold of 120 kN·m and the advance speed parameter is less than the first speed threshold of 0.05 m / min in the standby state. In the prediction state, the driving torque parameter is collected at a fixed sampling period of 50 ms, and the ratio of the mean to the standard deviation of the torque sequence is calculated as the volatility. When the volatility is less than the volatility threshold of 0.15 and the duration exceeds the first time threshold of 5 s, a confirmation trigger signal is output. When the volatility is greater than or equal to 0.15, the unit returns to the standby state and resets the prediction state timer. The coupling determination unit is used to synchronously collect drive torque parameters and advance speed parameters at a fixed sampling period of 50ms in the confirmation state. When the drive torque parameter is continuously greater than the torque confirmation threshold of 150kN·m, the advance speed parameter is continuously less than the speed confirmation threshold of 0.05m / min, and the product of the two is continuously less than the coupling lower limit threshold of 10kN·m·m / min, and the duration reaches the second time threshold of 5s, a switching trigger signal is output. The transition control unit is used to decrease the speed command value by a preset speed decrease step of 2 r / min and a control cycle of 200ms during the switching transition state. When the drive torque parameter exceeds the limit torque threshold of 190kN·m, the decrease is paused and the current speed is maintained until the speed drops below the low speed threshold of 8 r / min, after which a mode switching command is output. If the torque continues to exceed the limit for more than 3 seconds, the switching is judged to be abnormal and the system returns to the standby state. The back-cut determination unit is used to determine when the driving torque parameter is less than the second torque threshold of 80kN·m and the advance speed parameter is greater than the second speed threshold of 0.3m / min under the impact operation state, and to enter the back-cut determination state. After the duration exceeds the third time threshold of 10s, the back-cut command is output. If the torque or speed recovers during the period, the unit will forcibly return to the impact operation state and reset the timer. The mode switching output module is used to output a mode switching command when entering the switching transition state. Specifically, it outputs a 24V switch signal to the control terminal of the power switching device through the digital output port of the PLC to drive the solenoid valve to complete the power transmission path switching. The storage module stores various threshold parameters, including: first torque threshold 120 kN·m, first speed threshold 0.05 m / min, second torque threshold 80 kN·m, second speed threshold 0.3 m / min, torque confirmation threshold 150 kN·m, speed confirmation threshold 0.05 m / min, coupling lower limit threshold 10 kN·m·m / min, first time threshold 5 s, second time threshold 5 s, third time threshold 10 s, fourth time threshold 3 s, fifth time threshold 3 s, reset time threshold 2 s, fluctuation threshold 0.15, ultimate torque threshold 190 kN·m, low speed threshold 8 r / min, minimum pressure threshold 0.5 MPa, speed decrease step size 2 r / min, control cycle 200 ms, sampling cycle 50 ms, and sliding window length 100.

[0036] The above is a detailed description of the preferred embodiments of the present invention, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A dual-mode drilling switching control method for a rotary drilling rig, employing a finite state machine to model and control the drilling mode switching process, wherein the finite state machine includes a standby state, a prediction state, a confirmation state, a switching transition state, an impact operation state, and a return-cut determination state, characterized in that... The method includes: S1. Real-time acquisition of the driving torque parameters and advance speed parameters of the rotary drilling component; S2. In standby mode, when the driving torque parameter is greater than the first torque threshold and the advance speed parameter is less than the first speed threshold, the system enters the pre-judgment state. S3. In the prediction state, when the comparison result in S2 is held continuously for a longer time than the first time threshold and the fluctuation rate of the driving torque parameter is less than the fluctuation threshold, the system enters the confirmation state. S4. In the confirmed state, when the product of the driving torque parameter and the advance speed parameter continues to exceed the coupling threshold and exceeds the second time threshold, the system enters the switching transition state. S5. In the transition state, after controlling the rotation speed of the rotary drilling component to drop below the low speed threshold according to the preset slope, output the mode switching command to switch the drilling mode from soil rotary drilling mode to down-the-hole hammer impact drilling mode and enter the impact operation state. S6. In the impact operation state, when the driving torque parameter is less than the second torque threshold and the advance speed parameter is greater than the second speed threshold, the system enters the back-cut determination state. In the back-cut determination state, when the above state continues to exceed the third time threshold, the system controls the drilling mode to switch back to the soil rotary drilling mode and returns to the standby state.

2. The control method according to claim 1, characterized in that, In step S1, the driving torque parameter is obtained by acquiring the three-phase current signal of the rotary drilling component drive motor and performing coordinate transformation. Axis current components, and according to The relationship between shaft current components and torque is obtained through conversion. The advance speed parameter is obtained by collecting pulse signals from a displacement sensor or encoder and then processing them through a moving average filter.

3. The control method according to claim 1, characterized in that, In step S3, the fluctuation rate of the driving torque parameter is determined as follows: During the predicted duration, drive torque parameters are collected at a fixed sampling period to obtain the results from... Torque sequence composed of sample values Calculate the mean of the torque sequence. and standard deviation Standard deviation with the mean The ratio is used as volatility; When the volatility is less than the volatility threshold, the torque is determined to be in a stable high-load state, and entry into the confirmation state is allowed; When the volatility is greater than or equal to the volatility threshold, the torque is determined to be in an unstable state, and the system returns to the standby state and resets the prediction state's advance time.

4. The control method according to claim 1, characterized in that, In step S4, the determination that the product of the driving torque parameter and the advance speed parameter continuously exceeds the coupling threshold and exceeds the second time threshold is made using a sliding window determination method. During the duration of the confirmation state, drive torque parameters are synchronously acquired at a fixed sampling period. and advance speed parameters Calculate the coupling parameters at each sampling time. ; With length as The sliding window iterates through the sequence of coupling parameters. When all coupling parameters in the sliding window are within the sequence... When all values ​​are greater than the coupling threshold and the duration of the sliding window reaches the second time threshold, it is determined to be a hard rock formation and enters a switching transition state; When any coupling parameter appears in the sliding window If the value is less than or equal to the coupling threshold, clear the confirmation state timer and restart counting.

5. The control method according to claim 1, characterized in that, In step S4, the coupling threshold is determined as follows: In the rotary drilling mode of soil layer, the driving torque parameters and advance speed parameters of historical working conditions are collected at a fixed sampling period. The torque-speed product at each sampling time is calculated, and the statistical upper quantile value of the torque-speed product under normal soil layer drilling conditions is taken as the coupling threshold. The statistical quantile values ​​are the 90th to 95th percentile values.

6. The control method according to claim 1, characterized in that, In step S5, the rotational speed of the rotary drilling component is reduced to below a low-speed threshold at a preset slope, employing slope reduction control logic, including: Decrease by preset speed step size and control cycle Each control cycle decreases the speed command value by one step until the current speed is lower than the low speed threshold. During the speed reduction process, the drive torque parameter is monitored in real time. If the drive torque parameter exceeds the limit torque threshold, the reduction is paused and the current speed command value is kept unchanged until the drive torque parameter recovers to below the limit torque threshold and then the reduction continues. If the driving torque parameter exceeds the limit torque threshold for a period of time exceeding the fourth time threshold during the speed reduction process, it is determined to be a switching abnormality, the mode switching is terminated and the system returns to standby state, and an abnormal alarm command is output.

7. The control method according to claim 1, characterized in that, In the impact operation mode, the air supply pressure parameter of the down-the-hole hammer is acquired in real time. When the air supply pressure parameter is lower than the minimum pressure threshold, the impact operation mode is forcibly exited and returned to the standby mode, and a shutdown protection command is output at the same time. When the gas supply pressure parameter is lower than the minimum pressure threshold and the duration exceeds the fifth time threshold, an emergency shutdown command is output.

8. The control method according to claim 1, characterized in that, The finite state machine is equipped with state interlocking logic, specifically: Only a one-way state transition is allowed: standby state → prediction state → confirmation state → switching transition state → impact operation state → back-cut judgment state → standby state; If the judgment condition in any state is not met and the duration exceeds the reset time threshold, the system will be forced to return to the standby state and the timer and intermediate variables of that state will be reset. In the impact operation state, it is only allowed to return to the standby state through the back-cut judgment state, and it is prohibited to jump directly from the impact operation state to the prediction state or the confirmation state. If the speed is not reduced to below the low speed threshold during the transition state, it is prohibited to enter the impact operation state. In the back-cut determination state, if the driving torque parameter recovers to a value greater than the first torque threshold or the advance speed parameter recovers to a value less than the first speed threshold, it is determined that the formation has not completed the switching, and the system is forced to return to the impact operation state and reset the timing of the back-cut determination state.

9. A dual-mode drilling switching control system for a rotary drilling rig, used to implement the method as described in any one of claims 1-8, characterized in that, include: The parameter acquisition module is used to acquire the driving torque parameters and advance speed parameters of the rotary drilling component in real time. The state machine control module stores a finite state machine model, which includes a standby state, a prediction state, a confirmation state, a switching transition state, an impact operation state, and a back-cut determination state. The state machine control module controls the state switching according to the output of the parameter acquisition module and the state transition conditions. The mode switching output module is used to output a mode switching command when entering the switching transition state; The storage module is used to store various threshold parameters.

10. The system according to claim 9, characterized in that, The state machine control module includes a prediction determination unit, a coupling determination unit, a transition control unit, and a back-cut determination unit; The prediction and determination unit is used to enter the prediction state when the driving torque parameter is greater than the first torque threshold and the advance speed parameter is less than the first speed threshold in the standby state. In the prediction state, the driving torque parameter is collected at a fixed sampling period, and the ratio of the mean to the standard deviation of the torque sequence is calculated as the volatility. When the volatility is less than the volatility threshold and the duration exceeds the first time threshold, a confirmation trigger signal is output. When the volatility is greater than or equal to the volatility threshold, the unit returns to the standby state and resets the prediction state timer. The coupling determination unit is used to synchronously collect drive torque parameters and advance speed parameters at a fixed sampling period in the confirmation state, calculate the product of the two as the coupling parameter, and traverse the coupling parameter sequence with a sliding window. When all coupling parameters in the sliding window are greater than the coupling threshold and the duration reaches the second time threshold, a switching trigger signal is output. When a coupling parameter in the sliding window is less than or equal to the coupling threshold, the confirmation state timer is cleared. The transition control unit is used to decrease the speed command value according to a preset speed decrease step size and control cycle in the switching transition state, and to stop decreasing and maintain the current speed when the driving torque parameter exceeds the limit torque threshold, until the speed drops below the low speed threshold and then outputs the mode switching command. If the torque continues to exceed the limit and exceeds the fourth time threshold, the switching is determined to be abnormal and the unit returns to the standby state. The back-cut determination unit is used to enter the back-cut determination state when the driving torque parameter is less than the second torque threshold and the advance speed parameter is greater than the second speed threshold under the impact operation state, and outputs the back-cut command after the duration exceeds the third time threshold. If the torque or speed recovers during the period, it will be forced to return to the impact operation state and the timer will be reset.

Images