A hydraulic inhole drill rotating speed control method based on load compensation

Abstract

The application discloses a kind of hydraulic tunnel drilling rig rotating speed control method based on load compensation, comprising the following steps: step 1) the dynamic model and steady-state model of the hydraulic tunnel drilling rig rotation system are established;Step 2) based on the step response test results of the drilling rig rotation system, the dynamic model parameters are identified;Step 3) based on the dynamic model model identified in step 2), an extended state observer is designed to estimate the influence of load torque and perform feedforward compensation;Step 4) based on the dynamic model after feedforward compensation, a PI controller is designed using pole placement to achieve speed tracking;Step 5) based on the steady-state model, a dead zone compensator is designed to overcome the valve dead zone, control the input of the steady-state model to be close to the actual required valve opening, and achieve fast tracking response of the rotating speed. The application can effectively solve the problem of rotating speed fluctuation during drilling, significantly improve the stability and safety of the drilling rig rotating speed. The control system has strong adaptability and can maintain accurate tracking of the rotating speed under different drilling conditions, providing effective support for the intelligent control of coal mine drilling rigs.

Description

Technical Field

[0001] This invention relates to a method for controlling the rotational speed of a hydraulic tunnel drilling rig based on load compensation, belonging to the field of automatic control technology for mining engineering machinery. Background Technology

[0002] Hydraulic tunnel drilling rigs are core equipment in coal mine tunnel drilling. Their drilling operations are completed collaboratively by the feed system, rotary system, and circulation system. The feed system applies axial pressure to ensure the cutting teeth of the PDC drill bit maintain close contact with the formation, ensuring the drill bit cuts into the formation using an effective shearing method. The rotary system provides stable torque and rotational speed, enabling the drill bit to achieve efficient rotary cutting, using the ultra-hard material and excellent sharpness of the cutting teeth to shear and break up the formation. The circulation system uses circulating media to promptly carry the cutting debris out of the borehole, preventing debris accumulation from affecting drilling efficiency. It also cools the drill bit, lubricates the drilling tools, and cleans the borehole wall, thus ensuring smooth drilling and stable borehole quality. Rotational speed is a key operating parameter in the drilling process, significantly impacting rig speed and increasing drilling stability. To achieve intelligent drilling, the rotational speed must track the recommended rotational speed, thereby achieving safe and efficient drilling. However, due to the often unknown and variable hardness of the formation, the load torque generated during drilling is complex and diverse, leading to drastic fluctuations in the rig's rotation speed, making it difficult to maintain stability and accurately track the desired value. Therefore, precise control of the rotation speed is crucial for improving drilling efficiency.

[0003] Currently, research on drilling rig rotary systems mainly focuses on two directions: first, optimizing the rotational speed and drilling pressure settings to achieve stable operation of the rotary system. For example, the literature (Lan Bo, Zhu Yong, Gao Qiang, et al. Study on dynamic characteristics of drilling rig rotary system under load speed regulation in different formations [J]. Machine Tool & Hydraulics, 2024, 52(16):118-127.) divides the formation according to the firmness coefficient and gives the recommended rotational speed for the corresponding formation to ensure the smooth operation of the rotary system. However, these methods are mostly still in the numerical simulation stage and have not yet been widely applied in industry. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a hydraulic tunnel drilling rig speed control method based on load compensation, which aims to maintain the drilling rig rotation speed stable under any load and track the set value, thereby improving drilling speed and borehole quality and reducing the probability of drilling accidents.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for controlling the rotational speed of a hydraulic tunnel drilling rig based on load compensation includes the following steps:

[0007] Step 1) Establish the dynamic and steady-state models of the hydraulic tunnel drilling rig's rotation system;

[0008] Step 2) Identify the dynamic model parameters based on the experimental results of the step response of the drilling rig rotation system;

[0009] Step 3) Based on the dynamic model identified in Step 2), design an extended state observer to estimate the impact of load torque and perform feedforward compensation.

[0010] Step 4) Based on the dynamic model after feedforward compensation, a PI controller is designed using pole placement to achieve speed tracking;

[0011] Step 5) Based on the steady-state model, design a dead zone compensator to overcome the valve dead zone and control the input of the steady-state model to a valve opening degree close to the actual requirement, so as to achieve a fast tracking response of the rotational speed.

[0012] Optionally, the dynamic model of the drilling rig rotation system in step 1) is:

[0013]

[0014] Where, ω m The value represents the rotational speed, in r / s; T is the time constant of the reduced-order system; and Kq represents the valve orifice flow gain, in meters. 3 / s·m, where s is the Laplace transform variable, I PWM For control signals, dimensionless, K xv For gain, D m The displacement of the hydraulic motor is expressed in meters (m). 3 / rad; C tm The total leakage coefficient m of the hydraulic motor 3 / (s·Pa), V t The total compression volume (m³) of the hydraulic motor's two chambers and connecting pipes. 3 ,β e The effective bulk modulus of the oil (Pa); T L The load torque (Nm) generated by the drill bit cutting the formation.

[0015] Optionally, the steady-state model of the drilling rig rotation system in step 1) is:

[0016]

[0017] Where I0 is the control signal when the drilling rig's slewing system starts to operate, and a and b are parameters obtained by least squares fitting based on the control signal and steady-state value of the rotation speed of the slewing system under normal operating conditions.

[0018] Optionally, the specific content of step 2) is:

[0019] By using the step response data of the drilling rig's slewing system—that is, the system's rotational speed response to a step control input—the least squares method is used to identify the dynamic parameters of the slewing system, obtaining parameters T and... The value of .

[0020] Optionally, the specific content of step 3) is:

[0021] Design an extended state observer:

[0022]

[0023] Where z1 is ω m The observed value, z2 is f(T) L The observed values ​​of z1 and z2 are [β1β2], where [β1β2] is the observer gain; the dot (.) above z1 and z2 denotes the derivative.

[0024] Let e1 = ω m -z1, The observation error of the state observer can be expressed as:

[0025]

[0026] Where h is the derivative of f;

[0027] Let the characteristic equation of the observation error of the state observer be (s+ω0). 2 , ω0>0, where ω0 is the expected eigenvalue of the system, we can obtain:

[0028]

[0029] Design disturbance compensation amount based on the observations of the extended state observer.

[0030] Feedforward compensation theoretically eliminates the influence of load changes on rotational speed.

[0031] Optionally, step 4) uses a pole-placement approach to design a PI controller to achieve speed tracking. Specifically:

[0032] Based on the compensated dynamic model system, the PI controller parameters are designed using the pole placement method, and the transfer function of the PI controller is set as follows:

[0033]

[0034] This represents the error between the measured and expected values ​​of the rotational speed, where s represents the Laplace transform variable, and K... i K represents the integral parameter in the PI controller. p This represents the proportional parameter in the PI controller;

[0035] Solving for controller parameters:

[0036]

[0037] ζ is the damping, dimensionless, ω n The natural oscillation frequency is expressed in rad / s.

[0038] Optionally, the dead-zone compensation step in step 5) is designed as follows:

[0039]

[0040] Where, ω r To set the rotational speed, rad / s, I z The generated feedforward compensation is dimensionless. a and b are parameters obtained by least squares fitting based on the control signal and steady-state value of the rotational system under normal operating conditions.

[0041] Optionally, step 6) is also included, which uses simulation and field experiments to verify the effectiveness and rationality of the proposed load-compensated hydraulic tunnel drilling rig speed control method.

[0042] Optional, specifically including:

[0043] Based on the Matlab / Simulink simulation platform, a speed controller and a model of the slewing system were built, and field experiments were conducted on the ZDY4500LFK drilling rig.

[0044] The beneficial effects achieved by this invention are as follows:

[0045] This invention effectively solves the problem of rotational speed fluctuation during drilling, significantly improving the stability and safety of the drilling rig's rotational speed. The control system has strong adaptability and can maintain precise tracking of the rotational speed under different drilling conditions, providing effective support for the intelligent control of coal mine drilling rigs. Attached Figure Description

[0046] Figure 1 This is a structural diagram of the drilling rig's rotary system;

[0047] Figure 2 This is a diagram of the speed control structure for a hydraulic tunnel drilling rig;

[0048] Figure 3 It is the steady-state response curve of the rotary system;

[0049] Figure 4 It is the steady-state characteristic curve of the rotary system;

[0050] Figure 5These are the step response signal of the drilling rig rotation system and the output signal of the identification model;

[0051] Figure 6 These are simulation results of the rotary system under no-load conditions;

[0052] Figure 7 It is the disturbance change curve;

[0053] Figure 8 It is the response curve of the rotary closed-loop system after applying a load;

[0054] Figure 9 These are observations from the extended state observer;

[0055] Figure 10 It is the speed change curve during the load start-up process;

[0056] Figure 11 These are the output curves of each module of the controller;

[0057] Figure 12 This is the rotation speed change curve during normal drilling. Detailed Implementation

[0058] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0059] The load-compensated hydraulic tunnel drilling rig speed control method of the present invention includes the following steps:

[0060] Step 1) Establish the dynamic and steady-state models of the hydraulic tunnel drilling rig's rotation system;

[0061] Step 2) Identify dynamic model parameters using the step response data of the drilling rig's rotation system;

[0062] Step 3) Based on the dynamic model, design an extended state observer to estimate the impact of load torque and perform feedforward compensation;

[0063] Step 4) Based on the compensated dynamic model, a PI controller is designed using pole placement to achieve speed tracking;

[0064] Step 5) Based on the system steady-state model, design a dead-zone compensator to overcome the valve dead zone;

[0065] Step 6) Verify the effectiveness and rationality of the proposed load-compensated hydraulic tunnel drilling rig speed control method using simulation and field experiments.

[0066] The aforementioned method for controlling the rotational speed of a hydraulic tunnel drilling rig based on load compensation, specifically step 1), includes the following:

[0067] The dynamic performance of the drilling rig's slewing system is primarily determined by the load-sensitive proportional valve and the hydraulic motor. The load-sensitive proportional valve consists of a drive circuit and a valve body. The drive circuit adjusts the valve core displacement x using a PWM signal output from the controller. v The unit is m. Because the electronic control system has a fast response speed, a linear element is used to describe the dynamic characteristics of the drive circuit. Its dynamic model is as follows:

[0068] x v =K xv I PWM ;

[0069] Among them, K xv For gain, I PWM To control the dimensionless input signal, the dynamic model of the valve body of the load-sensitive proportional valve is as follows:

[0070]

[0071] Among them, P s Let P1 be the inlet pressure of the load-sensitive proportional valve, Pa, and P2 be the inlet and outlet pressures of the hydraulic motor, Pa. We define the load flow rate of the hydraulic motor as q. L Unit m 3 / s, load pressure is P L =P1-P2. During drilling, the load-sensitive system changes the inlet pressure according to the load pressure, C d Flow coefficient, W valve orifice shape coefficient m 2 x v Indicates valve spool displacement, in meters (m); ρ represents hydraulic oil density, in kilograms per cubic meter of water. 3 To satisfy:

[0072] P s =P L +P d ;

[0073] Among them, P d Given a constant value, the dynamic model of the load-sensitive proportional valve body can be simplified as follows:

[0074]

[0075] make

[0076]

[0077] We can obtain:

[0078] q L =K q x v ;

[0079] Since the normal operating range of the drilling rig is 60r / min-180r / min, the system will not frequently cross the zero point. Therefore, its dead zone characteristics are not considered in the process of establishing the dynamic model.

[0080] A hydraulic motor converts the kinetic energy of the liquid pressure provided by a hydraulic pump into the mechanical energy of its output shaft. Based on the continuity of flow, the dynamic flow continuity equation of a hydraulic motor can be obtained as follows:

[0081]

[0082] Where, ω m D represents rotational speed, in r / s; m This refers to the displacement of the hydraulic motor, measured in meters (m). 3 / r (cubic meters per revolution); the unit of rotational speed is rad / s (radians per second); C tm Vt is the total leakage coefficient of the hydraulic motor, expressed in L / min·bar; Vt is the total compression volume of the two chambers and connecting pipes of the hydraulic motor, expressed in m³. 3 βe is the effective bulk modulus of the hydraulic fluid, measured in Pa·s (Pa·s). Based on the torque balance of the hydraulic motor, the dynamic torque balance equation for the rotating shaft of the hydraulic motor can be obtained as follows:

[0083]

[0084] Among them, J t The equivalent total inertia of the hydraulic motor shaft is kg·m 2 T L Let Nm be the load torque generated by the drill bit cutting the formation. Combining the above formulas, the mathematical model of the drilling rig rotation system can be obtained as follows:

[0085]

[0086] Although the theoretical dynamic model of the rotary system is a second-order system, in actual operation, the rotary speed does not exhibit obvious oscillatory characteristics when the valve opening changes, indicating that the drilling rig's rotary system is an overdamped system. To simplify the controller design, this invention reduces the rotary system to a first-order model, i.e.

[0087]

[0088] Where, ω m The value represents the rotational speed, in r / s; T is the time constant of the reduced-order system; and Kq represents the valve orifice flow gain, in meters. 3 / s·m, where s is the Laplace transform variable, I PWM For control signals, dimensionless, K xv For gain, D m The displacement of the hydraulic motor is expressed in meters (m).3 / rad; C tm The total leakage coefficient m of the hydraulic motor 3 / (s·Pa), V t The total compression volume (m³) of the hydraulic motor's two chambers and connecting pipes. 3 ,β e The effective bulk modulus of the oil (Pa); T L The load torque (Nm) generated by the drill bit cutting the formation;

[0089] The steady-state model of the slewing system primarily reflects its dead-zone characteristics. When the control signal is small, the slewing speed cannot dynamically change with the control signal, no longer conforming to the previously described dynamic model. To overcome the influence of dead-zone characteristics on the system's startup control, steady-state values ​​of the slewing speed under different control signals were obtained through experimental testing. A piecewise function was then used to fit the relationship between the control signal and the slewing speed, yielding the system's steady-state model. This can be expressed mathematically as follows:

[0090]

[0091] Where I0 is the control signal when the drilling rig's slewing system starts to operate, and a and b are parameters obtained by least squares fitting based on the control signal and steady-state value of the rotation speed of the slewing system under normal operating conditions.

[0092] The specific content of step 2) of the aforementioned load-compensated hydraulic tunnel drilling rig speed control method is as follows:

[0093] By using the control signal and speed change data of the step response of the slewing system, the least squares method is employed to identify the system parameters, obtaining parameters T and... The value of .

[0094] The aforementioned hydraulic tunnel drilling rig speed control method based on load compensation, step 3) specifically describes the following: During drilling, changes in drilling conditions alter the load torque on the drill bit cutting the formation, and these changes in the load torque of the slewing system make it difficult to stabilize the drilling rig's speed. Furthermore, since there are unidentified parameters in the influence channel of load torque on speed, this implementation example will consider the influence of the system's load torque. Defined as an extended state, the rotary system is then re-expressed as:

[0095]

[0096] Based on this, the extended state observer is designed as follows:

[0097]

[0098] Where z1 is ω m The observed values, f and f(T)L The same representation means that z2 is the observed value of f. [β1β2] is the observer gain. Let e1 = ω m -z1, The observation error of the state observer can be expressed as:

[0099]

[0100] Where h is the derivative of f. For the rotary system of the drilling rig, h is bounded, and it can be proven that the observation errors e1 and e2 gradually converge and are bounded (ZHENG Q, Gaol LQ, GAO Z. On stability analysis of active disturbance rejection control for nonlinear time-varying plants with unknown dynamics[C].In Proceedings of 46th IEEE conference on decision and control.New Orleans, USA, 2007:3501-3506.).

[0101] Let the characteristic equation of the observation error of the state observer be (s+ω0). 2 ω0>0, where ω0 is the expected eigenvalue of the system.

[0102]

[0103] To eliminate the influence of load torque on rotational speed, this patent designs a disturbance compensation amount I based on the observations of the extended state observer. D .

[0104]

[0105] Feedforward compensation theoretically eliminates the influence of load changes on rotational speed.

[0106] The aforementioned load-compensated hydraulic tunnel drilling rig speed control method, step 4) specifically involves: designing the PI controller parameters using a pole placement approach based on the compensated system. The PI controller transfer function is:

[0107] This represents the error between the measured and expected values ​​of the rotational speed, where s represents the Laplace transform variable, and K... i K represents the integral parameter in the PI controller. p This represents the proportional parameter in the PI controller;

[0108] The closed-loop transfer function of the gyratory system is:

[0109]

[0110] in, The rotary closed-loop system is a typical second-order system. Its performance indicators, natural oscillation frequency, and damping satisfy the following relationship:

[0111]

[0112] Where Mp is the overshoot, expressed as a percentage; the damping ratio (ζ) is a dimensionless value; t s The time is adjusted, with the unit being seconds; the natural oscillation frequency is ω. n The unit is rad / s. Based on the expected settling time and overshoot of the desired rotary closed-loop system, we can obtain the constraints that the damping ratio and natural oscillation frequency must satisfy. By configuring the damping ratio and natural oscillation frequency of the closed-loop system, the characteristic equation of the closed-loop system can be obtained as follows:

[0113]

[0114] The controller parameters can be solved by matching the corresponding coefficients.

[0115]

[0116] The aforementioned load-compensated hydraulic tunnel drilling rig speed control method, step 5), specifically involves using the inverse function of the steady-state characteristics of the rotary system as the dead-zone compensation for the controller. This achieves the goal of quickly adjusting the system's operating point to the steady-state response region, avoiding performance degradation caused by the dead-zone effect. The designed dead-zone compensation mechanism is as follows:

[0117]

[0118] Where, ω r The set rotational speed is rad / s, Iz is the generated feedforward compensation quantity, which is dimensionless, and a and b are parameters obtained by least squares fitting based on the control signal and steady-state value of the rotational system under normal operating conditions.

[0119] The aforementioned load-compensated hydraulic tunnel drilling rig speed control method, step 6) specifically involves: building a slewing system speed controller and a slewing system model based on the Matlab / Simulink simulation platform, and conducting field experiments on a ZDY4500LFK drilling rig. Simulation and experiments demonstrate the effectiveness and rationality of the proposed method.

[0120] This invention first establishes steady-state and dynamic models of the drilling rig's slewing system, and identifies dynamic model parameters using field data to fit the steady-state model. Based on the dynamic model, an extended state observer is designed, successfully estimating the influence of load torque on rotational speed. Simultaneously, by combining a feedforward compensation strategy, the impact of load torque variations on rotational speed is effectively suppressed. Furthermore, a PI controller is designed using the pole placement method to ensure precise tracking control of the slewing system's rotational speed. Based on the steady-state model, a dead-zone compensator is designed to effectively overcome the negative impact of the dead-zone effect on system performance.

[0121] Example 1:

[0122] In this implementation example, the structure of the drilling rig rotation system is as follows: Figure 1 As shown in the diagram. The slewing system regulates the opening of the load-sensitive proportional valve by adjusting the PWM modulation signal output by the speed controller, thereby controlling the flow of hydraulic oil into the hydraulic motor and regulating the slewing speed. The load-sensitive pump in the system senses the load pressure and adjusts the output pressure of the main pump to compensate for load disturbances caused by drill bit cutting, thus maintaining speed stability. The structural diagram of the slewing control system is shown below. Figure 2 As shown.

[0123] Step 1) Establish the dynamic and steady-state models of the hydraulic tunnel drilling rig's rotation system;

[0124] Based on theoretical analysis, the theoretical dynamic model of the drilling rig rotation system is as follows:

[0125]

[0126] Reduce the dynamic model to first order, i.e.

[0127]

[0128] In the process of constructing the steady-state model of the slewing system, steady-state values ​​of the slewing speed under different control signals were obtained through experimental testing, such as... Figure 3 As shown. Based on this, a piecewise function was used to fit the relationship between the valve opening and the rotational speed, and the steady-state model of the system was obtained. Figure 4 Its mathematical expression is:

[0129]

[0130] Step 2) Identify dynamic model parameters using the step response data of the drilling rig's rotation system;

[0131] The system parameters were identified using the least squares method, resulting in the following mathematical model of the control signal to speed in the slewing system:

[0132]

[0133] This implementation example compares the actual output value with the model output value under the same input signal, and the results are as follows: Figure 5 As shown, the model output closely matches the actual measured data of the system, indicating that the identified model can accurately reflect the dynamic characteristics of the slewing system, providing a reliable foundation for subsequent controller design.

[0134] Step 3) Based on the dynamic model, design an extended state observer to estimate the impact of load torque and perform feedforward compensation;

[0135] The designed extended state observer is as follows:

[0136]

[0137] Where z1 is the observed rotational speed, and z2 is f(T) L Let the characteristic equation of the observer be λ0=(s+ω0). 2 Since ω0 > 30, the relevant parameter β1 in the observer can be calculated as 2ω0 - 10.99 = 49.01.

[0138] The feedforward compensation amount based on this design is:

[0139]

[0140] Feedforward compensation theoretically eliminates the influence of load torque on rotational speed.

[0141] Step 4) Based on the identified dynamic model, a PI controller is designed using pole placement to achieve speed tracking.

[0142] The transfer function of the closed-loop system is:

[0143]

[0144] The desired settling time of the rotary closed-loop system is less than 2 seconds, and the overshoot is less than 5%. To achieve the desired performance, the damping and natural oscillation frequency need to satisfy ζ > 0.69, ω n >3.86, In this implementation example, the selected parameter is ζ = 0.85, ω n =6.5, at this time the characteristic equation of the closed-loop system is: s 2 +11.05s + 42.25 = 0. Comparing this with the characteristic equation of the closed-loop system, and by making the corresponding coefficients equal, the parameters of the PI controller can be obtained as follows:

[0145] K p =0.0034,K i =2.344;

[0146] Step 5) Based on the system steady-state model, design a dead zone compensator to overcome the valve dead zone.

[0147] Using the inverse function of the steady-state model of the slewing system, a feedforward compensation module is designed to overcome the influence of the dead zone on the system. The designed dead zone compensation element for the slewing system is as follows:

[0148] I z =0.8197ω r -106.19;

[0149] Step 6) Verify the effectiveness and rationality of the proposed load-compensated hydraulic tunnel drilling rig speed control method using simulation and field experiments.

[0150] Under no-load conditions, the performance of the slewing system is mainly reflected in its ability to track the setpoint and its dynamic response characteristics. Simulations verified the closed-loop performance of the system under no-load conditions. The speed tracking curve and the observer's results are shown below. Figure 6 As shown, under no-load conditions, the slewing speed stabilizes near the set value within 2 seconds without exhibiting significant overshoot. Simultaneously, the extended state observer effectively observes the slewing speed, and the observed stable value for the extended state is 0, which is in line with our expectations.

[0151] Under load conditions, the load is as follows Figure 7 As shown, the speed tracking effect is as follows: Figure 8 As shown, in the 0-3s range, the output of the slewing control system depends on the PI controller; therefore, the PI controller and the controller in this embodiment have the same response curve. When the rotational speed reaches near the set value, it is affected by a disturbance signal, causing the rotational speed to fluctuate around the set value. The PI controller adjusts the control quantity solely based on the drilling speed error signal, resulting in a large fluctuation range in the rotational speed. In contrast, the slewing system designed in this embodiment utilizes an extended state observer to effectively observe the load effect, such as... Figure 9 As shown, it generates corresponding control quantities, effectively reducing the impact of disturbances on the slewing system.

[0152] We designed an experiment to simulate the effect of constant load disturbance on the rotary system under drill bit contact with the formation. The experimental results are as follows: Figure 10 As shown. Traditional PI controllers only focus on the system's tracking performance during design, neglecting disturbance suppression capabilities. Therefore, although they can eventually stabilize near the setpoint, their response speed is significantly reduced, making it difficult to quickly respond to load disturbances. In contrast, the speed controller designed in this implementation example can observe the impact of load torque in real time and generate corresponding control quantities (such as...). Figure 11As shown in the diagram, feedforward compensation effectively counteracts the influence of load torque on the system. Experiments show that under the action of the speed controller designed in this patent, the slewing system can still stabilize to near the set value within 3 seconds, and keep the steady-state error within the range of ±3 r / min. Furthermore, Figure 11 The output of each module of the controller is shown, further verifying the significant robustness and rapid response capability of the controller designed in this implementation example when dealing with load disturbances.

[0153] During normal drilling, the curve of the rotational speed change is as follows: Figure 12 As shown, the cutting process causes more drastic fluctuations in rotational speed, but the steady-state error of the rotational speed remains within ±3 r / min, demonstrating strong robustness.

[0154] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A method for controlling the rotational speed of a hydraulic tunnel drilling rig based on load compensation, characterized in that, Includes the following steps: Step 1) Establish the dynamic and steady-state models of the hydraulic tunnel drilling rig rotation system; the dynamic model of the drilling rig rotation system is as follows: ； in, The value represents the rotational speed, in r / s; T is the time constant of the reduced-order system. K q This represents the valve orifice flow gain, m³ / s·m, where s is the Laplace transform variable. For control signals, dimensionless. K xv For gain, D m The displacement of the hydraulic motor is expressed in m³ / rad. C tm The total leakage coefficient of the hydraulic motor is m³ / (s·Pa). V t The total compression volume (m³) of the two chambers of the hydraulic motor and the connecting pipes. The effective bulk modulus of the oil is Pa. T L The load torque (Nm) generated by the drill bit cutting through the formation; Step 2) Identify the dynamic model parameters based on the experimental results of the step response of the drilling rig rotation system; Step 3) Based on the dynamic model identified in Step 2), design an extended state observer to estimate the impact of load torque and perform feedforward compensation. Step 4) Based on the dynamic model after feedforward compensation, a PI controller is designed using pole placement to achieve speed tracking; Step 5) Based on the steady-state model, design a dead zone compensator to overcome the valve dead zone and control the input of the steady-state model to a valve opening degree close to the actual requirement, so as to achieve a fast tracking response of the rotational speed.

2. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1, characterized in that, The steady-state model of the drilling rig rotation system in step 1) is: ； in, I 0 is the control signal for when the drilling rig's rotation system starts operating. a and b These parameters are obtained by fitting the control signal and steady-state speed of the rotary system under normal operating conditions using the least squares method.

3. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1 or 2, characterized in that, The specific content of step 2) is as follows: By using the step response data of the drilling rig's slewing system—that is, the system's rotational speed response to a step control input—the least squares method is used to identify the dynamic parameters of the slewing system and obtain the parameters. T and The value of .

4. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1 or 2, characterized in that, The specific content of step 3) is as follows: Design an extended state observer: ； in, z 1 is The observed values, z 2 is f Observations , For observer gain; z 1 and z 2. The dot above represents the derivative; f represents the effect of the system's load torque. make , The observation error of the state observer is expressed as: in h for f The derivative; Let the characteristic equation of the observation error of the state observer be: , For the desired eigenvalues ​​of the system, we get: ； Design disturbance compensation amount based on the observations of the extended state observer. ; Feedforward compensation theoretically eliminates the influence of load changes on rotational speed.

5. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1 or 2, characterized in that, Step 4) involves designing a PI controller using pole placement to achieve speed tracking. The specific details are as follows: Based on the compensated dynamic model system, the PI controller parameters are designed using the pole placement method, and the transfer function of the PI controller is set as follows: ； This is expressed as the error between the measured rotational speed and the expected value. Denotes the Laplace transform variable. This represents the integral parameter in the PI controller; This represents the proportional parameter in the PI controller; Solving for controller parameters: ； , For damping, dimensionless, The natural oscillation frequency is expressed in rad / s.

6. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1 or 2, characterized in that, The dead zone compensation step in step 5) is designed as follows: ； in, To set the rotational speed, rad / s, I z The resulting feedforward compensation is dimensionless. a and b These parameters are obtained by fitting the control signal and steady-state speed of the rotary system under normal operating conditions using the least squares method.

7. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 1 or 2, characterized in that, It also includes step 6), which uses simulation and field experiments to verify the effectiveness and rationality of the proposed load-compensated hydraulic tunnel drilling rig speed control method.

8. The hydraulic tunnel drilling rig speed control method based on load compensation according to claim 7, characterized in that, Specifically, it includes: Based on the Matlab / Simulink simulation platform, a speed controller and a model of the slewing system were built, and field experiments were conducted on the ZDY4500LFK drilling rig.

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