Hydraulic winch automatic bit feeding system based on shaft bottom bit pressure prediction and control method

Abstract

The invention discloses a hydraulic winch automatic bit feeding system based on shaft bottom bit pressure prediction and a control method. The system comprises a power unit, a driving unit, an execution unit and a control unit. The power unit is used for providing hydraulic energy or storing the hydraulic energy provided by the driving unit and providing controllable power output for the winch; the driving unit is used for converting hydraulic energy and mechanical energy to drive and change the rotating speed of a winch drum and the tension (ground bit pressure) of a dead rope section of a pulley block; the execution unit is used for mutual conversion of kinetic energy and gravitational potential energy, and drill column lifting and drill bit operation are achieved. The control unit is used for controlling the transmission direction of system energy and accurately controlling the rotating speed of the winch and the tension of the steel wire rope at the dead rope end of the pulley block to reach ideal set values.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent automatic drilling systems, and particularly to a hydraulic winch automatic drilling system and control method based on bottom-hole drill pressure prediction. Background Art

[0002] The intelligent oil automatic drilling system can complete the entire drilling process automatically without human intervention. Under different working conditions, it can change the hoisting speed of the drill string and the bottom-hole drill pressure, thereby effectively improving the drilling efficiency and operation safety.

[0003] The oil automatic drilling system has been relatively mature in drilling process control and can achieve precise regulation based on real-time downhole data and intelligent algorithms. However, in previous research on automatic drilling, many scholars' research focused on control algorithms. For example, in two core journals 1009 - 0134(2023)08 - 0132 - 04 and 1009 - 0134(2023)08 - 0132 - 04, the intelligent control goals of achieving a constant drilling speed and controlling the winch to achieve a constant drill pressure were quickly reached through control algorithms. Currently, there are still bottlenecks in the intelligent application of the hydraulic system, and the energy efficiency optimization and fault self-diagnosis technologies of the hydraulic system have not been fully integrated into the automatic drilling system, restricting its stability and adaptability under extreme working conditions. In the future, it is necessary to combine the intelligent hydraulic system and the control system. Summary of the Invention

[0004] In order to overcome the defects existing in the above technologies, the purpose of the present invention is to provide a hydraulic winch automatic drilling system and control method based on bottom-hole drill pressure prediction. The system is an automatic drilling hydraulic winch system established in AMEsim, which can significantly improve the drilling efficiency, safety and control accuracy. The hydraulic winch system can realize the rapid compensation of ground changes for the hoisting of the drill string and the ground drill pressure under different working conditions. In terms of control, through the hydraulic proportional valve and the Simulink control algorithm, the winch lowering speed is adjusted in real time to maintain a constant drill pressure and avoid "slipping" or "sticking" of the drill bit.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0006] A hydraulic winch automatic drilling system based on bottom-hole drill pressure prediction, the system includes a power unit, a drive unit, an execution unit and a control unit;

[0007] The power unit is used to provide hydraulic energy or store the hydraulic energy provided by the drive unit to provide a controllable power output for the winch;

[0008] The drive unit is used for the mutual conversion of hydraulic energy and mechanical energy to drive and change the rotation speed of the winch drum and the tension at the dead rope end of the pulley block (ground drill pressure);

[0009] The execution unit is used for the mutual conversion of kinetic energy and gravitational potential energy to realize the operation of lifting the drill string and the drill bit;

[0010] The control unit is used to control the transmission direction of the system energy, and accurately control the winch speed and the wire rope tension at the dead line end of the pulley block to reach the ideal set value.

[0011] Among them, the energy transfer from the power unit to the execution unit is the main energy transfer direction of the system, and the energy transfer from the execution unit to the power unit is the secondary energy transfer direction of the system.

[0012] The power unit includes a constant pressure pump group, a fixed displacement pump group, and an accumulator;

[0013] The constant pressure pump group dynamically adjusts the displacement of the variable oil cylinder through a constant pressure valve to control the output flow of the variable pump to reach a constant pressure. The fixed displacement pump group includes a relief valve and a fixed displacement pump to achieve a constant flow. The accumulator is connected to the fixed displacement pump group to provide a large instantaneous flow, and has the functions of storing energy, absorbing flow shocks, and compensating for leakage losses.

[0014] The drive unit includes a proportional servo valve, a variable mechanism, a variable mechanism, and an axial piston motor / pump;

[0015] The constant pressure pump group, the proportional servo valve, and the variable mechanism are connected to realize the change of the swash plate angle of the piston motor / pump;

[0016] The fixed displacement pump group, the accumulator, and the proportional servo valve are respectively connected to the variable mechanism to respectively realize the rotation of the axial piston motor / pump and the change of the wire rope tension at the dead line end of the pulley block;

[0017] The proportional servo valve adopts a three-position four-way H type. By switching the spool position, the flow direction of the hydraulic oil is changed to control the telescopic movement of the hydraulic cylinder and the change of the swash plate angle of the piston motor / pump, so that the speed of the winch and the wire rope tension of the winch system both change accordingly.

[0018] The execution unit includes a winch drum, a brake, a speed reducer, a drill string, a wire rope, and a spring damper;

[0019] The winch drum is used to provide speed to realize the change of the lifting speed of the drill string; the brake is used to be connected to the winch drum and is used to immediately brake the winch drum in case of an emergency during drilling operations; the speed reducer is used to reduce the lifting speed of the drill string through the speed reducer when the winch drum rotates at a high speed; the drill string and the spring damper are respectively used to simulate the elasticity of the drill string, and the wire rope of the pulley block is used to connect to the drill string to realize the lifting operation of the drill string.

[0020] The control unit includes an angle sensor, a speed sensor, a displacement sensor, a force sensor, and a simulation interface;

[0021] The proportional servo valve is connected to the angle sensor, the rotational speed sensor, and the simulation interface. The angle sensor is used to receive the angle signal of the swash plate inclination angle of the axial piston motor / pump, output the angle signal from the drawworks system, and input it into the controller. The rotational speed sensor receives the rotational speed signal of the drawworks drum, outputs the rotational speed signal from the drawworks system, and inputs it into the controller to achieve the control of the drill string hoisting speed. The proportional servo valve is connected to the displacement sensor, the force sensor, and the simulation interface. The displacement sensor is used to receive the displacement signal of the variable mechanism pulley, output the displacement signal from the drawworks system, and input it into the controller. The force sensor is used to receive the tension signal at the dead line end of the pulley block, output the tension signal from the drawworks system, and input it into the controller to achieve the control of the wire rope tension at the dead line end of the pulley block.

[0022] The simulation interface is used to input the signals in AMEsim into Simulink and input the signals in Simulink into AMEsim.

[0023] A control method for an automatic feed drilling system of a hydraulic drawworks based on bottom hole drill pressure prediction is as follows:

[0024] S1: Establish a mathematical model of the system according to the composition and working mechanism of the hydraulic drawworks system;

[0025] S2: Establish simulation models of the power unit, the drive unit, and the execution unit in AMEsim according to the mathematical logic relationship and energy transfer relationship between the components in the system, and form an automatic feed drilling system for the hydraulic drawworks;

[0026] S3: Establish a compound control model of the drawworks hydraulic system in Simulink according to the mathematical logic relationship and energy transfer relationship between the components in the system;

[0027] S4: Use Simulink as an intermediate simulation platform, input the angle sensor signal of the axial piston motor inclination angle, the rotational speed sensor signal of the drawworks drum, the piston displacement sensor signal of the piston cylinder, and the wire rope tension sensor signal in the automatic feed drilling system of the hydraulic drawworks described in S2 into Simulink. Then, according to the theoretical analysis and calculation based on the working conditions required by the operator during drilling operations, set the rotational speed of the drawworks drum and the wire rope tension in the controller to form a deviation from the signals input into Simulink, and output an electrical signal to the electro-hydraulic servo valve in AMEsim through the compound control model of the drawworks hydraulic system described in S3 to achieve precise control of the automatic feed drilling hydraulic system of the drawworks.

[0028] The specific content of S1 is as follows:

[0029] Establish the input-output formula of the power unit according to the composition and working mechanism of the hydraulic drawworks system:

[0030]

[0031] In the formula, q hpu is the flow rate of the constant-pressure oil source, and q lpu is the flow rate of the fixed-displacement pump oil source, V hp is the displacement of the constant-pressure dynamic pump, and V lp is the displacement of the low-pressure pump, n hp is the rotational speed of the constant-pressure pump, and n lp is the rotational speed of the low-pressure pump, V lg0 is the volume of the accumulator of the fixed-displacement pump, and p lg0 is the pre-charge pressure of the accumulator of the fixed-displacement pump;

[0032] According to the composition and working mechanism of the designed hydraulic winch system, establish the input-output mathematical modeling formula of the drive unit:

[0033]

[0034] In the formula, Msu is the output torque of the secondary unit, and q leak is the leakage flow rate of the secondary unit, and n su is the rotational speed of the secondary unit, and U va is the control voltage;

[0035] According to the composition and working mechanism of the designed hydraulic winch system, establish the input-output mathematical modeling formula of the execution unit:

[0036]

[0037] In the formula, X load is the load displacement, and F ts is the wire rope tension;

[0038] According to the composition and working mechanism of the designed hydraulic winch system, establish the input-output mathematical modeling formula of the control unit:

[0039] U va = f va (X ds , X load , n su , F ts )

[0040] According to the mathematical logic relationship and energy transfer relationship among the units and components in the hydraulic winch system, establish the simulation models of the power unit, drive unit, and execution unit on the AMEsim simulation platform, and establish the simulation model of the control unit on the Matlab / Simulink simulation platform to form the overall co-simulation model of the automatic pipe-racking hydraulic winch system.

[0041] The specific content of S2 is as follows:

[0042] S2.1: Based on the mathematical logic relationships and energy transfer relationships among the components in the system, establish the simulation models of the power unit, drive unit, and execution unit in AMEsim to form the automatic drill feeding system of the hydraulic winch.

[0043] S2.2: On the basis of the model built in AMEsim described in S2.1, since the power element provides the hydraulic power source and the fixed-displacement pump group generally cannot meet the requirement that the winch speed and the wire rope tension quickly reach the set values, an accumulator is equipped to provide a large instantaneous flow rate and jointly provide the oil source with the fixed-displacement pump group.

[0044] The drive unit drives the winch to rotate and changes the wire rope tension. The proportional servo valve switches the spool position, changes the flow direction of the hydraulic oil, changes the angle of the variable mechanism and the displacement of the variable mechanism, thereby changing the inclination angle of the axial piston motor and the tension of the wire rope of the pulley block. The execution unit changes the hoisting speed of the drill string and the bit weight on bit. The changes in the axial piston motor and the variable mechanism cause changes in the winch drum speed and the wire rope tension. When the bit starts to work, the given signal brake controls the winch speed to the lowest for rock breaking, and the bottom hole bit weight is realized through the variable mechanism. The damping spring simulates the elasticity of the drill string and the friction force in the wellbore.

[0045] The control unit sends command signals, receives signals and feedback signals. The angle sensor and the speed sub-model form a double closed-loop control to accurately control the hoisting speed of the drill string, and the displacement sensor and the force sensor also form a double closed-loop control to accurately control the bit weight on bit.

[0046] S2.3: Take the VisualStudio compiler as the transfer medium between AMEsim and Simulink. In the AMEsim software, generate a simulation interface module through the Interface module to build an interface for data transmission with Simulink. The input end of the simulation interface module is connected to the angle, speed, displacement, and force sensors, and the output end is connected to the proportional servo valve for controlling the winch speed and the proportional servo valve for controlling the wire rope tension at the dead line end.

[0047] The specific content of S3 is as follows:

[0048] S3.1: Based on the mathematical logic relationships and energy transfer relationships among the components in the system, establish the simulation model of the control unit in Simulink to form the control system of the automatic drill feeding of the hydraulic winch.

[0049] S3.2: In Simulink, when conducting drilling operations according to the operator, through the working condition requirements, theoretical analysis and calculation are carried out to obtain the hoisting speed of the drill string and the surface drilling pressure based on the prediction of the bottom hole drilling pressure as the research adjustment signal. The difference between the rotational speed signal and the tension signal output by the rotational speed sensor and the force sensor in S2 is used as the feedback signal, and the rotational speed deviation e1 and the tension deviation e2 are obtained;

[0050] S3.3: In Simulink, the control of the wire rope tension is unstable, and a feedforward compensation control is added to the winch tension controller;

[0051] The influence of the disturbance on the tension is predicted through a mathematical model to generate a reverse compensation signal, and its mathematical model is:

[0052] u ff =K ff ·(m·a + F friction )

[0053] Where: the feedforward control amount u ff ; the load mass m; the acceleration a; the friction force F friction ;

[0054] S3.4: The fuzzy module adopts a two-input and three-output form; among them, the deviation is e and the deviation change rate is e c , and the three coefficient change amounts ΔK P , ΔK I , ΔK D are used as the output values of the analog control. The membership functions all use triangular membership functions to establish the corresponding relationship between the input quantity and the output quantity. The universes of discourse of the input quantity and the output quantity fuzzy subsets are all expressed as:

[0055] {NB, NM, NS, ZO, PS, PM, PB}

[0056] Where, NB represents negative large, NM represents negative medium, NS represents negative small, ZO represents zero, PS represents positive small, PM represents positive medium, and PB represents positive large; the accurate values of e and e c are input and transformed into fuzzy membership degrees through the input membership function to obtain E and EC;

[0057] S3.5: Establish fuzzy control rules to perform the conversion from the input signal error and the error change rate to ΔK P , ΔK I , ΔK D ;

[0058] S3.6: The ΔK P , ΔK I , ΔK D output in S3.5 is respectively combined with K P , KI and K D are added together to implement the control parameters in the PID controller.

[0059] Specifically, S4 is as follows:

[0060] S4.1: In the winch hydraulic system, the inner loop of the winch speed controller is that the angle sensor receives the swash plate inclination signal of the axial piston motor / pump and inputs it into the winch speed controller. The signal output of the winch speed controller is sent to the proportional servo valve as a conventional PID. The outer loop is that the speed sensor receives the winch drum speed signal and inputs it into the winch speed controller as the winch speed PID control. A fuzzy control is added to its outer loop to form a double closed-loop composite controller. The winch speed forms a deviation from the speed set value. Through the double closed-loop composite controller, the winch speed can quickly reach the expectation. The inner loop of the winch tension controller is that the displacement sensor receives the piston displacement signal in the variable mechanism and inputs it into the winch tension controller. The signal output of the winch tension controller is sent to the proportional servo valve as a conventional PID. The outer loop is that the force sensor receives the wire rope tension signal at the dead line end of the pulley block and inputs it into the winch tension controller as the winch tension PID control. A feedforward compensation control and a fuzzy control are added to its outer loop to form a double closed-loop composite controller. The wire rope tension forms a deviation from the tension set value. Through the double closed-loop composite controller, the surface drilling pressure can quickly reach the expected value.

[0061] Advantages of the present invention:

[0062] The simulation modeling method for the hydraulic winch automatic pipe feeding system and control method makes full use of the modeling and simulation advantages of different software in their respective disciplinary fields, builds a co-simulation model, and realizes the control of the drill string lifting speed and the wire rope tension at the dead line end of the pulley block in the hydraulic winch system, which can significantly improve the drilling efficiency, safety and control accuracy. Specifically, the following advantages:

[0063] 1. By using the AMEsim and Simulink co-simulation model, the software advantages of AMEsim in hydraulic system simulation and Simulink in control simulation are fully utilized, the modeling process is simplified, and the accuracy of the simulation is improved.

[0064] 2. According to the working principle of the set system, a graphical modeling method is adopted, avoiding complex mathematical models, and facilitating the modification of complex system components and diversified design; The double closed-loop composite controller is built with the professional control element library of Simulink. A fuzzy control and a feedforward compensation control are added to it, making the simulation results more intuitive and easy to analyze. At the same time, it verifies that the AMEsim-Simulink co-simulation can more accurately control the hydraulic winch system. Description of the Drawings

[0065] Figure 1This is the working principle diagram of the hydraulic system for the automatic feed drilling winch.

[0066] Figure 2 This is the AMEsim simulation model of the hydraulic system for the automatic feed drilling winch.

[0067] Figure 3 This is the Matlab / Simulink simulation model of the automatic feed drilling controller.

[0068] The reference signs in the figure are as follows:

[0069] 1 - Constant pressure pump unit; 2 - Fixed displacement pump unit; 3 - Accumulator; 4 - Proportional servo valve; 5 - Swash plate angle variable mechanism of piston motor; 6 - Displacement variable mechanism; 7 - Piston motor / pump; 8 - Winch drum; 9 - Brake; 10 - Reducer; 11 - Drill string load; 12 - Steel wire rope; 13 - Spring damper; 14 - Angle sensor; 15 - Speed sensor; 16 - Displacement sensor; 17 - Force sensor; 18 - Control simulation interface; 19 - Winch hoisting controller; 20 - Winch steel wire rope tension controller; 21 - Feedforward compensation controller; 22 - Fuzzy control. Specific implementation mode

[0070] The present invention will be further described in detail below with reference to the accompanying drawings.

[0071] As Figure 1 shown, the present invention is applied to the automatic feed drilling system of the hydraulic winch in the oil field as the research object, and the working principle diagram of the designed hydraulic winch system is used to realize the control of the winch speed and the surface drilling pressure at the dead line end of the pulley block.

[0072] As Figure 2 shown, according to the working principle diagram of the system, a graphical modeling method is adopted in the AMEsim software to establish the simulation model of the hydraulic system; a hydraulic winch automatic feed drilling system based on bottom hole drilling pressure prediction, the system includes a power unit, a drive unit, an execution unit and a control unit;

[0073] The power unit is used to provide hydraulic energy or store the hydraulic energy provided by the drive unit, and provide a controllable power output for the winch;

[0074] The drive unit is used for the mutual conversion of hydraulic energy and mechanical energy, and drives to change the speed of the winch drum and the tension (surface drilling pressure) at the dead line end of the pulley block;

[0075] The execution unit is used for the mutual conversion of kinetic energy and gravitational potential energy to realize the operation of hoisting the drill string and the drill bit;

[0076] The control unit is used to control the transmission direction of the system energy, and accurately control the winch speed and the steel wire rope tension at the dead line end of the pulley block to reach the ideal set value.

[0077] Among them, the energy transfer from the power unit to the execution unit is the main energy transfer direction of the system, and the energy transfer from the execution unit to the power unit is the secondary energy transfer direction of the system.

[0078] The power unit includes a constant-pressure pump group 1, a fixed-displacement pump group 2, and an accumulator 3;

[0079] The constant-pressure pump group 1 dynamically adjusts the displacement of the variable oil cylinder through a constant-pressure valve to control the output flow of the variable pump to achieve constant pressure. The fixed-displacement pump group 2 includes a relief valve and a fixed-displacement pump to achieve a constant flow. The accumulator 3 is connected to the fixed-displacement pump group 2 to provide a large instantaneous flow, and has functions such as storing energy, absorbing flow shocks, and compensating for leakage losses;

[0080] The drive unit includes a proportional servo valve 4, variable mechanisms 5, 6, and an axial piston motor / pump 7;

[0081] The constant-pressure pump group 1, the proportional servo valve 4, and the variable mechanism 5 are connected to achieve a change in the swashplate angle of the piston motor / pump 7;

[0082] The fixed-displacement pump group 2, the accumulator 3, the proportional servo valve 4, and the variable mechanism 6 are connected to respectively achieve the rotation of the axial piston motor / pump and the change in the wire rope tension at the dead line end of the pulley block;

[0083] The proportional servo valve 4 is of the three-position four-way H type. By switching the spool position, it changes the flow direction of the hydraulic oil to control the telescoping of the hydraulic cylinder, thereby controlling the change in the swashplate angle of the piston motor, so that the rotational speed of the winch and the wire rope tension of the winch system both change accordingly;

[0084] The execution unit includes a winch drum 8, a brake 9, a speed reducer 10, a drill string 11, a wire rope 12, and a spring damper 13;

[0085] The winch drum 8 is used to provide rotational speed to achieve a change in the hoisting speed of the drill string 11; the brake 9 is used to be connected to the winch drum 8 and is used to immediately brake the winch drum in case of an emergency during drilling operations; the speed reducer 10 is used to reduce the hoisting speed of the drill string 11 through the speed reducer when the rotational speed of the winch drum is relatively fast; the drill string 11 and the spring damper 13 are respectively used to simulate the drill string and the elasticity of the drill string, and the pulley block wire rope 12 is used to connect to the drill string 11 to achieve the hoisting operation of the drill string.

[0086] The control unit includes an angle sensor 14, a rotational speed sensor 15, a displacement sensor 16, a force sensor 17, and a simulation interface 18;

[0087] The proportional servo valve 4, angle sensor 14, rotational speed sensor 15 and simulation interface 18 are connected. The angle sensor 14 is used to receive the angle signal of the swash plate inclination angle of the axial piston motor / pump 7, output the angle signal from the drawworks system, and input it into the controller; the rotational speed sensor 15 receives the rotational speed signal of the drawworks drum 8, outputs the rotational speed signal from the drawworks system, and inputs it into the controller to achieve the control of the drill string hoisting speed; the proportional servo valve 4, displacement sensor 16, force sensor 17 and simulation interface 18 are connected. The displacement sensor 16 is used to receive the displacement signal of the pulley of the variable mechanism 6, output the displacement signal from the drawworks system, and input it into the controller; the force sensor 17 is used to receive the tension signal at the dead line end of the pulley block, output the tension signal from the drawworks system, and input it into the controller to achieve the control of the steel wire rope tension at the dead line end of the pulley block;

[0088] The simulation interface 18 is used to input the signals in AMEsim into Simulink and input the signals in Simulink into AMEsim.

[0089] A control method for an automatic pipe feeding system of a hydraulic drawworks based on bottom hole drill pressure prediction is as follows:

[0090] S1: According to the composition and working mechanism of the designed hydraulic drawworks system, and based on the mechanism, reveal the mathematical logic relationship and energy transfer relationship between the main components, and establish a mathematical model of the system;

[0091] S2: According to the mathematical logic relationship and energy transfer relationship between the components in the system, establish simulation models of the power unit, drive unit and execution unit in AMEsim to form an automatic pipe feeding system of the hydraulic drawworks;

[0092] S3: According to the mathematical logic relationship and energy transfer relationship between the components in the system, establish a compound control model of the drawworks hydraulic system in Simulink;

[0093] S4: Use Simulink as an intermediate simulation platform, input the signals of the axial piston motor inclination angle sensor 14, drawworks drum rotational speed sensor 15, piston cylinder piston displacement sensor 16 and steel wire rope tension sensor 17 in the automatic pipe feeding system of the hydraulic drawworks described in S2 into Simulink. Then, according to the theoretical analysis and calculation based on the working conditions required by the operator during drilling operations, the rotational speed of the drawworks drum and the steel wire rope tension need to be set in the controller to form a deviation from the signals input into Simulink. The compound control model of the drawworks hydraulic system described in S3 outputs an electrical signal to the electro-hydraulic servo valve in AMEsim to achieve precise control of the automatic pipe feeding hydraulic system of the drawworks.

[0094] The present invention verifies that the combined simulation of AMEsim - Simulink can more accurately control the designed winch hydraulic system.

[0095] The specific content of S1 is as follows:

[0096] According to the composition and working mechanism of the hydraulic winch system, establish the input - output formula of the power unit:

[0097]

[0098] In the formula, q hpu is the flow rate of the constant - pressure oil source, q lpu is the flow rate of the fixed - displacement pump oil source, V hp is the displacement of the constant - pressure dynamic pump, V lp is the displacement of the low - pressure pump, n hp is the rotational speed of the constant - pressure pump, n lp is the rotational speed of the low - pressure pump, V lg0 is the volume of the accumulator of the fixed - displacement pump, p lg0 is the pre - charge pressure of the accumulator of the fixed - displacement pump;

[0099] According to the composition and working mechanism of the designed hydraulic winch system, establish the input - output mathematical modeling formula of the drive unit:

[0100]

[0101] In the formula, Msu is the output torque of the secondary unit, q leak is the leakage flow rate of the secondary unit, n su is the rotational speed of the secondary unit, U va is the control voltage;

[0102] According to the composition and working mechanism of the designed hydraulic winch system, establish the input - output mathematical modeling formula of the execution unit:

[0103]

[0104] In the formula, X load is the load displacement, F ts is the wire rope tension;

[0105] According to the composition and working mechanism of the designed hydraulic winch system, establish the input - output mathematical modeling formula of the control unit:

[0106] U va = f va (X ds , X load , n su , F ts )

[0107] According to the mathematical and logical relationships and energy transfer relationships among the various units and components in the hydraulic winch system, simulation models of the power unit, drive unit, and execution unit are established on the AMEsim simulation platform, and a simulation model of the control unit is established on the Matlab / Simulink simulation platform to form an overall co-simulation model of the automatic pipe feeding hydraulic winch system.

[0108] The specific content of S2 is as follows:

[0109] S2.1: According to the mathematical and logical relationships and energy transfer relationships among the components in the system, simulation models of the power unit, drive unit, and execution unit are established in AMEsim to form an automatic pipe feeding system for the hydraulic winch.

[0110] S2.2: Based on the model built in AMEsim in S2.1, the power component provides a hydraulic power source. Generally, the fixed displacement pump group 2 cannot meet the requirements that the winch speed and the wire rope tension quickly reach the set values. Therefore, an accumulator 3 is equipped to provide a large instantaneous flow rate and jointly provide an oil source with the fixed displacement pump group 2.

[0111] The drive unit drives the winch to rotate and changes the wire rope tension. The proportional servo valve 4 switches the spool position, changes the flow direction of the hydraulic oil, changes the angle of the variable mechanism 5 and the displacement of the variable mechanism 6, thereby changing the inclination angle of the axial piston motor 7 and the tension of the wire rope 12 of the pulley block. The execution unit changes the hoisting speed of the drill string and the bit weight on bit. When the axial piston motor 7 and the variable mechanism 6 change, the winch drum 8 speed and the wire rope 12 tension change; when the bit starts to work, the given signal brake 9 controls the winch speed to the lowest for rock breaking, and the bit weight on bit is achieved through the variable mechanism 6. The damping spring 13 simulates the elasticity of the drill string 11 and the friction force in the wellbore.

[0112] The control unit sends command signals, receives signals, and feedback signals. The angle sensor 14 and the speed 15 sub-model form a double closed-loop control to accurately control the hoisting speed of the drill string, and the displacement sensor 16 and the force sensor 17 also form a double closed-loop control to accurately control the bit weight on bit.

[0113] S2.3: Use the VisualStudio compiler as the transfer medium between AMEsim and Simulink. In the AMEsim software, through the Interface module, a simulation interface module 18 is generated to build an interface for data transmission with Simulink; the input end of the simulation interface module 18 is connected to the angle 14, speed 15, displacement 16, and force (17) sensors, and the output end is connected to the proportional servo valve 4a for winch speed control and the proportional servo valve 4b for dead line end wire rope tension control.

[0114] The specific content of S3 is as follows:

[0115] S3.1: Establish a simulation model of the control unit in Simulink according to the mathematical logic relationship and energy transfer relationship among the components in the system, and form a control system for the automatic drill feeding of the hydraulic winch;

[0116] S3.2: In Simulink, when the operator conducts drilling operations, through the working condition requirements, conduct theoretical analysis and calculation to obtain the hoisting speed of the drill string and the surface drill pressure obtained based on the prediction of the bottom hole drill pressure as the research adjustment signal. Take the difference between the rotation speed signal and the tension signal output by the rotation speed sensor 15 and the force sensor 17 in S2 as the feedback signal, and the rotation speed deviation e1 and the tension deviation e2;

[0117] S3.3: In Simulink, when the wire rope tension control is unstable, add a feedforward compensation control 21 to the winch tension controller 20;

[0118] Predict the influence of the disturbance on the tension through the mathematical model, and generate a reverse compensation signal. Its mathematical model is:

[0119] u ff =K ff ·(m·a + F friction )

[0120] Where: the feedforward control quantity u ff ; the load mass m; the acceleration a; the friction force F friction ;

[0121] S3.4: The fuzzy module adopts the form of two inputs and three outputs; among them, the deviation is e and the deviation value change rate is e c , and the three coefficient change amounts ΔK P , ΔK I , ΔK D are used as the output values of the analog control. The membership functions all use triangular membership functions to establish the corresponding relationship between the input quantity and the output quantity. The universes of discourse of the input quantity and the output quantity fuzzy subsets are all expressed as:

[0122] {NB, NM, NS, ZO, PS, PM, PB}

[0123] Among them, NB represents negative large, NM represents negative medium, NS represents negative small, ZO represents zero, PS represents positive small, PM represents positive medium, and PB represents positive large; the accurate values of e and e c are input and transformed into fuzzy membership degrees through the input membership function to obtain E and EC;

[0124] S3.5: Establish fuzzy control rules to perform from the input signal error and error change rate to ΔK P , ΔK I, ΔK D conversion;

[0125] S3.6: Add the ΔK output by the said S3.5 P , ΔK I , ΔK D to K P , K I , K D respectively to implement the control parameters in the PID controller.

[0126] The said S4 is specifically as follows:

[0127] S4.1: In the winch hydraulic system, for the winch speed controller 19, the inner loop is that the angle sensor 14 receives the swash plate inclination signal of the axial piston motor / pump 7 and inputs it into the winch speed controller 19, and the signal output of the winch speed controller 19 is sent to the proportional servo valve 4a as a conventional PID. The outer loop is that the speed sensor 15 receives the winch drum 8 speed signal and inputs it into the winch speed controller 19 as the winch speed PID control. A fuzzy control 22 is added to its outer loop to form a double-closed-loop composite controller. The winch speed forms a deviation from the speed set value. Through the double-closed-loop composite controller, the winch speed can quickly reach the expectation. For the winch tension controller 20, the inner loop is that the displacement sensor 16 receives the piston displacement signal in the variable mechanism 6 and inputs it into the winch tension controller 20, and the signal output of the winch tension controller 20 is sent to the proportional servo valve 4b as a conventional PID. The outer loop is that the force sensor 17 receives the tension signal of the wire rope 12 at the dead line end of the pulley block and inputs it into the winch tension controller 20 as the winch tension PID control. A feedforward compensation control 21 and a fuzzy control 22 are added to its outer loop to form a double-closed-loop composite controller. The wire rope tension forms a deviation from the tension set value. Through the double-closed-loop composite controller, the surface drilling pressure can quickly reach the expected value.

[0128] As Figure 3 shown in the Matlab / Simulink software, the controller simulation model is established to achieve the expected values of the drill string lifting speed and the surface drilling pressure of the hydraulic winch.

Claims

1. A hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction, characterized in that: The system includes a power unit, a drive unit, an execution unit and a control unit; The power unit is used to provide hydraulic energy or store hydraulic energy provided by the drive unit, and provide controllable power output for the winch; The drive unit is used for mutual conversion of hydraulic energy and mechanical energy, driving the change of the rotation speed of the winch drum and the tension (ground drilling pressure) of the dead rope end of the pulley block; The execution unit is used to convert kinetic energy and gravitational potential energy into each other, so as to lift the drill string and the drill bit to perform the operation; The control unit is used to control the transmission direction of the system energy, and accurately control the winch rotation speed and the wire rope tension at the dead rope end of the pulley block to achieve the ideal set value.

2. The hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 1 is characterized in that: The power unit comprises a constant pressure pump group (1), a quantitative pump group (2), and an accumulator (3); the constant pressure pump group (1) dynamically adjusts the displacement of the variable oil cylinder through a constant pressure valve to control the output flow of the variable pump to achieve a constant pressure; the quantitative pump group (2) comprises a relief valve and a quantitative pump to achieve a constant flow; the accumulator (3) is connected to the quantitative pump group (2) to provide a large instantaneous flow and has the functions of storing energy, absorbing flow shock and compensating for leakage loss.

3. The hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 1 is characterized in that: The drive unit comprises a proportional servo valve (4), a variable mechanism (5), a variable mechanism (6), and an axial piston motor / pump (7); The constant pressure pump group (1), the proportional servo valve (4) and the variable mechanism (5) are connected to achieve the change of the swash plate inclination angle of the plunger motor / pump (7); The quantitative pump group (2), the accumulator (3), and the proportional servo valve (4) are respectively connected to the variable mechanism (6), so as to respectively realize the rotation of the axial piston motor / pump (7) and the change of the tension of the wire rope at the dead rope end of the pulley group; The proportional servo valve (4) is a three-position four-way H-type valve. By switching the valve core position, the flow direction of the hydraulic oil is changed, the extension and retraction of the hydraulic cylinder is controlled, and the change of the inclination angle of the plunger motor / pump (7) is controlled, so that the rotation speed of the winch and the wire rope tension of the winch system are changed accordingly.

4. The hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 1 is characterized in that: The execution unit comprises a winch drum (8), a brake (9), a reducer (10), a drill string (11), a steel wire rope (12) and a spring damper (13); The winch drum (8) is used to provide a rotation speed to achieve a change in the lifting speed of the drill string (11); the brake (9) is used to be connected to the winch drum (8) and is used to immediately brake the winch drum when an emergency situation occurs during drilling operations; the reducer (10) is used to reduce the lifting speed of the drill string (11) through the reducer when the winch drum rotates at a high speed; the drill string (11) and the spring damper (13) are used to simulate the elasticity of the drill string and the drill string respectively, and the pulley wire rope (12) is used to be connected to the drill string (11) to achieve the lifting operation of the drill string.

5. The hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 1 is characterized in that: The control unit comprises an angle sensor (14), a rotation speed sensor (15), a displacement sensor (16), a force sensor (17) and a simulation interface (18); The proportional servo valve (4), the angle sensor (14), the speed sensor (15) and the simulation interface (18) are connected. The angle sensor (14) is used to receive the angle signal of the swash plate inclination of the axial piston motor / pump (7), output the angle signal from the winch system, and input it into the controller; the speed sensor (15) receives the speed signal of the winch drum (8), outputs the speed signal from the winch system, and inputs it into the controller to achieve the control of the drilling string lifting speed; the proportional servo valve (4), the displacement sensor (16), the force sensor (17) and the simulation interface (18) are connected. The displacement sensor (16) is used to receive the displacement signal of the pulley of the variable mechanism (6), outputs the displacement signal from the winch system, and inputs it into the controller; the force sensor (17) is used to receive the tension signal of the dead rope end of the pulley group, outputs the tension signal from the winch system, and inputs it into the controller to achieve the wire rope tension control at the dead rope end of the pulley group; The simulation interface (18) is used to input the signals in AMEsim into Simulink, and to input the signals in Simulink into AMEsim.

6. A control method for a hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction, characterized in that: The details are as follows: S1: According to the structure and working mechanism of hydraulic winch system, establish the mathematical model of the system; S2: According to the mathematical logic relationship and energy transfer relationship between the components in the system, the simulation models of the power unit, drive unit and execution unit are established in AMEsim to form a hydraulic winch automatic drilling system; S3: Based on the mathematical logic relationship and energy transfer relationship between the components in the system, a composite control model of the winch hydraulic system is established in Simulink; S4: Using Simulink as an intermediate simulation platform, the signals of the axial piston motor inclination angle sensor (14), the winch drum speed sensor (15), the piston cylinder piston displacement sensor (16) and the wire rope tension sensor (17) in the hydraulic winch automatic drilling system described in S2 are input into Simulink. Then, according to the working condition requirements when the operator performs drilling operations, theoretical analysis and calculation are performed. The winch drum speed and wire rope tension required to be set in the controller form a deviation with the signal input into Simulink. The composite control model of the winch hydraulic system described in S3 outputs an electrical signal to the electro-hydraulic servo valve in AMEsim, thereby realizing precise control of the automatic drilling winch hydraulic system.

7. The control method of the hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 6 is characterized in that: The S1 is specifically as follows: According to the structure and working mechanism of the hydraulic winch system, the input-output formula of the power unit is established: In the formula, q hpu is the constant pressure oil source flow, q lpu is the flow rate of the oil source of the metering pump, V hp is the displacement of the constant pressure dynamic pump, V lp is the displacement of the low-pressure pump, n hp is the speed of the constant pressure pump, n lp is the low pressure pump speed, V lg0 is the volume of the metering pump accumulator, p lg0 Pre-charge pressure for metering pump accumulator; According to the structure and working mechanism of the designed hydraulic winch system, the input-output mathematical modeling formula of the drive unit is established: Where Msu is the output torque of the secondary unit, q leak is the leakage flow of the secondary unit, n su is the secondary unit speed, U va is the control voltage; According to the structure and working mechanism of the designed hydraulic winch system, the input-output mathematical modeling formula of the execution unit is established: Where, X load is the load displacement, F ts is the wire rope tension; According to the structure and working mechanism of the designed hydraulic winch system, the input-output mathematical modeling formula of the control unit is established: U va =f va (X ds ,X load ,n su ,F ts ) According to the mathematical logic relationship and energy transfer relationship between each unit and component in the hydraulic winch system, simulation models of the power unit, drive unit and execution unit are established in the AMEsim simulation platform, and a simulation model of the control unit is established in the Matlab / Simulink simulation platform to form an overall joint simulation model of the automatic drill feeding hydraulic winch system.

8. The control method of the hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 6 is characterized in that: The S2 is specifically as follows: S2.1: According to the mathematical logic relationship and energy transfer relationship between the components in the system, the simulation models of the power unit, drive unit and execution unit are established in AMEsim to form the hydraulic winch automatic drilling system; S2.2: Based on the AMEsim model described in S2.1, the power element provides a hydraulic power source, and is equipped with an accumulator (3) to provide a larger instantaneous flow, and together with the quantitative pump group (2) provides an oil source; The driving unit drives the winch to rotate and change the tension of the wire rope. The proportional servo valve (4) switches the valve core position, changes the flow direction of the hydraulic oil, changes the angle of the variable mechanism (5) and the displacement of the variable mechanism (6), thereby changing the inclination angle of the axial piston motor (7) and the tension of the pulley group wire rope (12). The execution unit changes the lifting speed of the drill string and the drilling pressure of the drill bit. The axial piston motor (7) and the variable mechanism (6) change, so that the speed of the winch drum (8) and the tension of the wire rope (12) change. When the drill bit starts to work, the signal brake (9) is given to control the speed of the winch to the minimum to break the rock. The magnitude of the drilling pressure at the bottom of the well is realized through the variable mechanism (6). The damping spring (13) simulates the elasticity of the drill string (11) and its friction in the wellbore. The control unit sends a command signal, a receiving signal and a feedback signal. The angle sensor (14) and the speed sub-model (15) form a double closed-loop control to accurately control the lifting speed of the drill string. The displacement sensor (16) and the force sensor (17) also form a double closed-loop control to accurately control the drilling pressure of the drill bit. S2.3: Using the Visual Studio compiler as a transmission medium between AMEsim and Simulink, a simulation interface module (18) is generated in the AMEsim software through the Interface module to build an interface for data transmission with Simulink; the input end of the simulation interface module (18) is connected to the angle sensor (14), the speed sensor (15), the displacement sensor (16) and the force sensor (17), and the output end is connected to the winch speed control proportional servo valve (4a) and the dead rope end wire rope tension control proportional servo valve (4b).

9. The control method of the hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 6 is characterized in that: The S3 is as follows: S3.1: According to the mathematical logic relationship and energy transfer relationship between the components in the system, a simulation model of the control unit is established in Simulink to form a control system for automatic drilling of hydraulic winch; S3.2: In Simulink, when the operator performs drilling operations, theoretical analysis and calculation are performed according to the working condition requirements to obtain the drill string lifting speed and the ground drilling pressure based on the bottom hole drilling pressure prediction as the research adjustment signal, and the speed signal and tension signal output by the speed sensor (15) and the force sensor (17) in S2 are used as the feedback signal and the difference between the input signal is the speed deviation e1 and the tension deviation e2; S3.3: In Simulink, the wire rope tension control is unstable, and a feedforward compensation control (21) is added to the winch tension controller (20); The influence of disturbance on tension is predicted by mathematical model, and reverse compensation signal is generated. The mathematical model is: u ff =K ff ·(m·a+F friction ) Where: Feedforward control quantity u ff ; load mass m; acceleration a; friction force F friction ; S3.4: The fuzzy module adopts the form of two inputs and three outputs; the deviation is e and the rate of change of the deviation value is e c , the three coefficient changes of PID ΔK P , ΔK I , ΔK D As the output value of the analog control, the membership function uses the triangular membership function to establish the corresponding relationship between the input and output. The domain of the fuzzy subsets of the input and output are expressed as: {NB,NM,NS,ZO,PS,PM,PB} Among them, NB means negative big, NM means negative medium, NS means negative small, ZO means zero, PS means positive small, PM means positive medium, and PB means positive big; e and e c The precise value input is converted into fuzzy membership through the input membership function to obtain E and EC; S3.5: Establish fuzzy control rules to convert input signal error and error change rate to ΔK P , ΔK I , ΔK D conversion; S3.6: Convert the ΔK output of S3.5 P , ΔK I , ΔK D Respectively with K P , K I , K D Add together to realize the control parameters in the PID controller.

10. The control method of the hydraulic winch automatic drilling system based on bottom hole drilling pressure prediction according to claim 6, characterized in that: The S4 is specifically: S4.1: In the winch hydraulic system, the inner loop of the winch speed controller (19) is an angle sensor (14) that receives the swash plate inclination angle signal of the axial piston motor / pump (7) and inputs it into the winch speed controller (19), and outputs the signal of the winch speed controller (19) to the proportional servo valve (4a) as a conventional PID, and the outer loop is a speed sensor (15) that receives the speed signal of the winch drum (8) and inputs it into the winch speed controller (19) as a winch speed PID control, and the outer loop is added with fuzzy control (22) to form a double closed-loop compound controller, and the winch speed forms a deviation with the speed setting value. Through the double closed-loop compound controller, the winch speed can be quickly realized to reach the desired speed; The inner loop of the winch tension controller (20) is a displacement sensor (16) that receives the piston displacement signal in the variable mechanism (6) and inputs it into the winch tension controller (20), and outputs the signal of the winch tension controller (20) to the proportional servo valve (4b) as a conventional PID. The outer loop is a force sensor (17) that receives the tension signal of the wire rope (12) at the dead rope end of the pulley block and inputs it into the winch tension controller (20) as the winch tension PID control. Feedforward compensation control (21) and fuzzy control (22) are added to the outer loop to form a double closed-loop composite controller. The wire rope tension forms a deviation with the tension setting value. Through the double closed-loop composite controller, the ground drilling pressure can be quickly achieved to reach the expected value.

Images