Hydraulic support lifting control method and device based on flow proportion and posture feedback

Abstract

The invention relates to the technical field of fully-mechanized coal mining automation control, and discloses a hydraulic support lifting control method and device based on flow proportion and attitude feedback, and the method comprises the steps that a controller establishes a physical parameter model, and the controller calculates the target flow of a stand column oil cylinder and the target flow of a bottom lifting oil cylinder according to a kinematics coupling model; the controller executes a feedforward and fuzzy PID composite control strategy, the controller generates a feedforward instruction and combines the feedforward instruction with the feedback control quantity to synthesize a final valve control instruction, and the controller drives the electro-hydraulic control valve set to act; the controller monitors the synchronous error of the adjacent hydraulic supports and corrects a final valve control instruction, and the controller monitors the speed matching state and executes attitude priority deviation correction; the controller judges whether lifting is completed or not according to the displacement of the stand column oil cylinder, the displacement of the bottom lifting oil cylinder and the pitch angle of the hydraulic support, and the controller executes valve port smooth closing logic. According to the invention, the track tracking precision and the dynamic response speed of the lifting frame are improved, the action synchronism and the attitude stability are ensured, and hydraulic impact is eliminated.

Description

Technical Field

[0001] This invention relates to the field of automated control technology in fully mechanized mining, specifically to a hydraulic support lifting control method and device based on flow ratio and attitude feedback. Background Technology

[0002] Hydraulic supports are key equipment in fully mechanized mining faces, and their main function is to provide effective roof support. In automated coal mining processes, hydraulic supports need to frequently perform actions such as raising, moving, and lowering the supports. Among these actions, raising the supports is the crucial link in ensuring timely and effective roof support connection.

[0003] Existing hydraulic support lifting control methods have some shortcomings. Traditional lifting control often employs simple open-loop control or closed-loop control based on single position feedback. Open-loop control cannot cope with load changes, leading to unstable hydraulic support movement speed and difficulty in accurately controlling the lifting posture. While closed-loop control with single position feedback can improve positioning accuracy, the inherent nonlinearity, time-varying nature of the hydraulic system, and load disturbances make it difficult for conventional PID controller parameters to adapt to complex operating conditions. This results in a lag in the system's dynamic response, making it prone to control overshoot and oscillation during sudden changes in roof load, thus affecting trajectory tracking accuracy.

[0004] Furthermore, existing control methods do not adequately consider the coordinated action of the column cylinder and the base-lifting cylinder. During the lifting process, the speed coordination between the extension of the column cylinder and the retraction of the base-lifting cylinder directly affects the pitch attitude of the hydraulic support. Existing technology lacks effective constraints on the ratio of the two cylinders' movement speeds, which can easily lead to the base-lifting cylinder retracting too quickly, causing the rear end of the support base to over-lift, resulting in a dangerous downward tilting of the top beam and affecting the support effect.

[0005] In scenarios involving the coordinated advancement of multiple hydraulic supports, existing technologies lack effective collaborative control mechanisms. Independent operation of each hydraulic support can easily lead to cumulative errors, resulting in inconsistent support group postures, disrupting the straightness of the working face, and affecting the operation of subsequent scraper conveyors and coal mining machines. Furthermore, current methods for determining the end of support lifting largely rely on single limit switches or pressure signals, providing a limited set of criteria that makes it difficult to ensure the hydraulic supports are in the correct support posture when reaching the target height. Sudden valve closure can also cause strong hydraulic shocks, damaging the lifespan of hydraulic components and affecting system stability.

[0006] Therefore, this invention proposes a hydraulic support lifting control method and device based on flow ratio and attitude feedback to overcome the shortcomings of the prior art. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a hydraulic support lifting control method and device based on flow ratio and attitude feedback. It solves the problem that existing control methods are unable to balance trajectory tracking accuracy and dynamic response speed under nonlinear load disturbance conditions. It also solves the problem of hydraulic support attitude instability caused by the lack of coordination between the column cylinder and the bottom lifting cylinder, as well as the technical problems of low synchronization accuracy between groups of hydraulic supports and large hydraulic shock when the valve is closed.

[0008] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of this invention provides a hydraulic support lifting control method based on flow ratio and attitude feedback, comprising the following steps: S1. The controller establishes a physical parameter model of the hydraulic support. Based on the hydraulic support lifting process parameters and kinematic coupling model, the controller calculates the target flow rate of the column cylinder and the target flow rate of the bottom lifting cylinder.

[0009] In this step, the controller determines the effective area of ​​the rodless chamber of the column cylinder, the effective area of ​​the rod chamber of the column cylinder, the effective area of ​​the extension chamber of the bottom lifting cylinder, and the effective area of ​​the return chamber of the bottom lifting cylinder based on the cylinder diameter of the column cylinder, the rod diameter of the column cylinder, the cylinder diameter of the bottom lifting cylinder, and the rod diameter of the bottom lifting cylinder.

[0010] The controller constructs a geometric constraint relationship describing the change of the hydraulic support top beam height and the hydraulic support pitch angle with the displacement of the column cylinder and the bottom lifting cylinder. It then performs a time-dependent differential operation on the geometric constraint relationship to establish a coupled differential equation system of cylinder action speed and support state change rate.

[0011] Based on the target height trajectory curve of the top beam, the target landing curve of the base, and the allowable attitude change range, the controller uses an inverse kinematics algorithm to solve the coupled differential equations to obtain the target velocities of the column cylinder and the bottom-lifting cylinder. Combining the effective area and target velocities, the controller generates the target flow rates of the column cylinder and the bottom-lifting cylinder, which serve as the system control references.

[0012] S2. The controller executes a composite control strategy based on feedforward and fuzzy PID. The controller generates a feedforward valve opening command based on the target flow of the column cylinder and the target flow of the bottom lifting cylinder, and generates a feedback control quantity based on the real-time status data collected by the sensor. The final valve control command is then synthesized and the electro-hydraulic control valve group is driven to move.

[0013] In this step, the controller calls the pre-stored flow characteristic data of the electro-hydraulic control valve group to construct the reverse valve port flow model. The reverse valve port flow model is used to calculate the basic opening required to maintain the target flow rate, and feedforward valve control commands for the column cylinder and the bottom-lifting cylinder are generated to improve the system's tracking and response speed to flow demand.

[0014] Simultaneously, the controller calculates the flow error and rate of change of flow error based on the target flow rate and actual flow rate of the column cylinder, and calculates the attitude error based on the target pitch angle and actual pitch angle. The controller uses a fuzzy inference system to receive the flow error, rate of change of flow error, and attitude error, and adjusts the proportional, integral, and derivative coefficients of the PID controller online to calculate the feedback control quantity to eliminate model uncertainty errors and external disturbance errors. The controller superimposes the feedforward valve opening command and the feedback control quantity to synthesize the final valve control command, driving the electro-hydraulic control valve assembly to actuate.

[0015] S3. The controller performs coordinated control and anomaly correction of the group of supports. During the process of driving the electro-hydraulic control valve group, the controller monitors the synchronization error between adjacent hydraulic supports and corrects the final valve control command based on the synchronization error. The controller monitors the speed coordination status of the column cylinder and the bottom lifting cylinder and performs attitude priority correction. The corrected final valve control command is used to continuously drive the hydraulic support to move.

[0016] In this step, the controller calculates the synchronization error by comparing the displacement or pitch angle of the column cylinders of the current hydraulic support with those of the adjacent hydraulic supports. When the synchronization error exceeds the synchronization error threshold, the controller generates a deceleration correction coefficient or an acceleration correction coefficient to dynamically adjust the final valve control command, ensuring the consistency of the support group's movements.

[0017] Simultaneously, the controller calculates the ratio of the actual lifting speed of the column cylinder to the actual retraction speed of the bottom-lifting cylinder. When the ratio is less than the safety threshold, it indicates a tendency for the rear end of the base to rise too high, causing the front end of the top beam to sag. The controller then forcibly limits the valve opening of the bottom-lifting cylinder. When the absolute value of the attitude error exceeds the attitude limit threshold, the controller pauses the synchronization error adjustment function and enters the attitude priority correction mode, prioritizing the adjustment of the hydraulic flow rate in the column cylinder to correct the pitch angle of the hydraulic support.

[0018] S4. The controller performs the lifting end judgment and steady-state control. The controller collects the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle that change under the final valve control command in real time. Based on the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle, the controller determines whether the lifting action is completed and executes the valve port smooth closing logic when the lifting action is completed.

[0019] In this step, the controller performs logical AND operations to check whether the column cylinder displacement reaches the target stroke, whether the bottom-lifting cylinder displacement is within the allowable error range, and whether the hydraulic support pitch angle is within the allowable range. When the lifting end condition is met, the controller no longer calculates the control quantity based on flow error and attitude error. Instead, it uses the final valve control command at the current moment as a reference and gradually reduces the final valve control command value until it reaches zero according to the preset linear decay slope. This prevents the valve from suddenly closing and causing hydraulic shock, ensuring that the hydraulic support smoothly enters the steady-state support mode.

[0020] A second aspect of the present invention provides a hydraulic support lifting control device based on flow ratio and attitude feedback, comprising: The system includes a controller, a sensor assembly, and an electro-hydraulic control valve assembly. The controller is connected to both the sensor assembly and the electro-hydraulic control valve assembly.

[0021] The controller is equipped with a liquid supply calculation module, a feedforward control module, a fuzzy PID feedback control module, and a coordinated adjustment logic module.

[0022] The liquid supply calculation module is used to calculate the effective working area of ​​the column cylinder and the bottom lifting cylinder based on the pre-stored geometric parameters, and transmit the effective working area to the target flow calculation stage to generate the flow control benchmark.

[0023] The feedforward control module receives the flow control reference and calculates the feedforward valve opening command by combining it with the pre-stored flow characteristic data of the electro-hydraulic control valve group.

[0024] The fuzzy PID feedback control module is used to receive real-time status data collected by the sensor group and calculate the feedback control quantity based on the fuzzy inference system.

[0025] The controller combines the feedforward valve opening command and the feedback control quantity to form the final valve control command. The coordinated adjustment logic module receives the synchronization error between adjacent hydraulic supports and generates a correction coefficient based on the synchronization error to correct the final valve control command.

[0026] The electro-hydraulic control valve assembly is used to respond to the final valve control command output by the controller and drive the column cylinder and the bottom lifting cylinder to move.

[0027] This invention provides a hydraulic support lifting control method based on flow ratio and attitude feedback. It has the following advantages: 1. This invention employs a composite control strategy based on flow ratio and attitude feedback. The controller constructs a kinematic coupling model and calculates the target flow rates of the column cylinder and the bottom-lifting cylinder. The feedforward control module provides basic opening commands based on the reverse valve port flow model. The fuzzy PID feedback control module uses a fuzzy inference system to adjust PID parameters online to compensate for model uncertainty errors. This composite control strategy significantly improves the trajectory tracking accuracy and dynamic response speed of the hydraulic support during the lifting process, solves the control lag problem caused by nonlinear load disturbances, and ensures the coordination of the column cylinder and the bottom-lifting cylinder's movements.

[0028] 2. This invention introduces a group support collaborative control and attitude priority correction mechanism. The controller monitors the synchronization error between adjacent hydraulic supports and dynamically corrects the final valve control command. Simultaneously, the controller calculates the speed ratio between the column cylinder and the bottom-lifting cylinder. When the speed ratio is less than the speed ratio safety threshold or the attitude error exceeds the attitude limit threshold, the controller triggers forced correction logic. This group support collaborative control and attitude priority correction mechanism effectively prevents the hydraulic support group from losing synchronization during the lifting process, avoids the phenomenon of the top beam tip sinking due to excessively rapid bottom lifting, and ensures the overall advancing attitude stability of the support group in the fully mechanized mining face.

[0029] 3. This invention designs a multi-parameter fusion-based lifting end determination and valve smooth closing logic. The controller comprehensively determines whether the displacement of the column cylinder, the displacement of the bottom-lifting cylinder, and the pitch angle of the hydraulic support simultaneously meet the target conditions. When the lifting action is determined to be complete, the controller gradually reduces the final valve control command according to a linear decay slope. The multi-parameter fusion-based lifting end determination logic ensures the accuracy of the hydraulic support's posture when it is in position, and the valve smooth closing logic eliminates hydraulic shock vibrations caused by sudden closure of the electro-hydraulic control valve group, extending the service life of hydraulic components and improving the stability of the hydraulic support when it enters the steady-state support mode. Attached Figure Description

[0030] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a block diagram of the present invention. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Please see Figure 1-2 This invention provides a hydraulic support lifting control method based on flow ratio and attitude feedback, comprising the following steps: S1. The controller establishes a physical parameter model of the hydraulic support. Based on the hydraulic support lifting process parameters and kinematic coupling model, the controller calculates the target flow rate of the column cylinder and the target flow rate of the bottom lifting cylinder. S2. The controller executes a composite control strategy based on feedforward and fuzzy PID. The controller generates a feedforward valve opening command based on the target flow of the column cylinder and the target flow of the bottom lifting cylinder, and generates a feedback control quantity based on the real-time status data collected by the sensor. The final valve control command is synthesized and the electro-hydraulic control valve group is driven to move. S3. The controller performs coordinated control and anomaly correction of the group of supports. During the process of driving the electro-hydraulic control valve group, the controller monitors the synchronization error between adjacent hydraulic supports and corrects the final valve control command based on the synchronization error. The controller monitors the speed coordination status of the column cylinder and the bottom lifting cylinder and performs attitude priority correction. The corrected final valve control command is used to continuously drive the hydraulic support to move. S4. The controller performs the lifting end judgment and steady-state control. The controller collects the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle that change under the final valve control command in real time. Based on the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle, the controller determines whether the lifting action is completed and executes the valve port smooth closing logic when the lifting action is completed.

[0033] See attached document Figure 1 This invention provides a hydraulic support lifting control method based on flow ratio and attitude feedback. By constructing a physical parameter model and real-time control loop for the hydraulic support, this invention achieves coordinated action control of the column cylinder and the bottom-lifting cylinder. This invention is applied to a hydraulic support system in a fully mechanized mining face. The hydraulic support system includes a top beam, a base, a shield beam, a linkage mechanism, column cylinders, and bottom-lifting cylinders. The column cylinders connect the base and the top beam, supporting the roof load and adjusting the top beam height. The bottom-lifting cylinders are installed between the base and the pushing mechanism or inside the base, used to adjust the base attitude and assist in the bottom-lifting action during the lifting process.

[0034] A sensor array is arranged in the hydraulic actuation circuit of the hydraulic support. This array includes pressure sensors installed on the inlet and return hydraulic lines of the column cylinder and the lifting cylinder, magnetostrictive displacement sensors installed on the strokes of the column cylinder and the lifting cylinder, and tilt sensors installed on the top beam or base. The pressure sensors collect real-time pressure data within the cylinder chambers. The magnetostrictive displacement sensors collect real-time displacement data of the column cylinder and the lifting cylinder. The tilt sensors collect pitch angle data of the hydraulic support. The controller is connected to the pressure sensors, magnetostrictive displacement sensors, and tilt sensors via signal transmission lines. The controller is also connected to the electro-hydraulic control valve group that drives the column cylinder and the lifting cylinder, receiving sensor data and outputting valve control commands.

[0035] The controller has pre-stored the geometric parameters of the hydraulic support column cylinder and the bottom-lifting cylinder, and runs a fluid supply calculation module based on these parameters. The fluid supply calculation module first defines the physical dimensions of the column cylinder. The cylinder diameter is set to... The rod diameter of the column cylinder is The maximum stroke of the column cylinder is .

[0036] The liquid supply calculation module also defines the physical dimensions of the lifting cylinder. The cylinder diameter of the lifting cylinder is set to... The rod diameter of the lifting cylinder is The maximum stroke of the bottom-lifting hydraulic cylinder is .

[0037] After establishing the effective area parameters of the hydraulic cylinder, the controller establishes a kinematic coupling model based on the mechanical structure of the hydraulic support. During the lifting process of the hydraulic support, the height of the top beam... With support pitch angle Displacement by column cylinder Displacement of the lifting cylinder A joint decision.

[0038] To achieve dynamic control of the lifting speed and attitude of the hydraulic support, the controller modulates the above positional relationship expression with respect to time. By performing differentiation, the coupled differential equations of the cylinder's movement speed and the bracket's attitude change are obtained.

[0039] The controller solves the aforementioned coupled differential equations based on the preset target height trajectory curve of the top beam, the bottom landing curve of the base, and the attitude constraints, to obtain the target velocity of the column cylinder required to maintain the target trajectory. With the target speed of the lifting cylinder During the hydraulic support lifting operation, the column cylinder extends, and hydraulic oil enters the rodless chamber of the column cylinder; the bottom-lifting cylinder retracts, and hydraulic oil is discharged from the return chamber of the bottom-lifting cylinder. The controller calculates the target speed of the column cylinder. With the target speed of the lifting cylinder Based on the effective area parameters, the target flow rate of the column cylinder is calculated. With the target flow rate of the bottom lifting cylinder .

[0040] See attached document Figure 2 In the implementation of flow and attitude coupling modeling based on cylinder geometry parameters, the controller first performs parameterized calculation of the effective area of ​​the cylinder. The controller's internal storage unit is pre-configured with the geometric parameters of the hydraulic support column cylinder and the bottom-lifting cylinder. These geometric parameters include the cylinder diameter of the column cylinder. Column cylinder rod diameter Column cylinder stroke Bottom lifting cylinder diameter Bottom-lifting cylinder rod diameter and the stroke of the bottom lifting cylinder .

[0041] The liquid supply calculation module retrieves the cylinder diameter of the column hydraulic cylinder from the controller's internal storage unit. and column cylinder rod diameter The fluid supply calculation module calculates the effective area of ​​the rodless chamber of the column cylinder based on the hydraulic transmission principle. Effective area of ​​the rodless chamber of the column cylinder The calculation formula is: ; In the formula, Defined as the effective area of ​​the rodless chamber of the column cylinder; Defined as pi (π). Defined as the cylinder diameter of the column hydraulic cylinder.

[0042] The fluid supply calculation module calculates the effective area of ​​the rod chamber of the column cylinder. Effective area of ​​the rod chamber of the column cylinder. The calculation formula is: ; In the formula, Defined as the effective area of ​​the rod-side chamber of a column-mounted hydraulic cylinder; Defined as the diameter of the column cylinder rod.

[0043] The liquid supply calculation module retrieves the cylinder diameter of the lifting cylinder from the controller's internal storage unit. and the diameter of the lifting cylinder rod The liquid supply calculation module calculates the effective area of ​​the extension chamber of the lifting cylinder. Effective area of ​​the lifting cylinder extension chamber. The calculation formula is: ; In the formula, Defined as the effective area of ​​the extension cavity of the bottom-lifting hydraulic cylinder; Defined as the diameter of the lifting cylinder.

[0044] The fluid supply calculation module calculates the effective area of ​​the return oil chamber of the bottom-lifting cylinder. Effective area of ​​the oil return chamber of the lifting cylinder The calculation formula is: ; In the formula, Defined as the effective area of ​​the oil return chamber of the bottom-lifting cylinder; Defined as the rod diameter of the lifting cylinder. The fluid supply calculation module calculates the effective area of ​​the rodless chamber of the column cylinder. Effective area of ​​the rod chamber of the column cylinder Effective area of ​​the lifting cylinder extension chamber and the effective area of ​​the oil return chamber of the bottom lifting cylinder Saved to the controller parameter register, the fluid supply calculation module calculates the effective area of ​​the rodless chamber of the column cylinder. Effective area of ​​the rod chamber of the column cylinder Effective area of ​​the lifting cylinder extension chamber and the effective area of ​​the oil return chamber of the bottom lifting cylinder It is transmitted as a parameter to the target traffic calculation stage.

[0045] After completing the parameterization calculation of the effective area of ​​the hydraulic cylinder, the controller executes the steps of establishing kinematic coupling relationships and solving for the target velocity. Based on the physical properties of the linkage mechanism and the position data of the hinge points of the hydraulic support, the controller constructs a kinematic coupling model describing the motion of the hydraulic support. The kinematic coupling model describes the geometric constraint relationship between the height of the hydraulic support top beam and the attitude angle of the hydraulic support as a function of the displacement of the column cylinder and the displacement of the bottom-lifting cylinder.

[0046] The controller defines the height of the hydraulic support top beam. Displacement of the column cylinder and displacement of the lifting cylinder The functional relationship. Height of the hydraulic support top beam. The function expression is: ; In the formula, Defined as time Height of the hydraulic support top beam; Defined as a time variable; Defined as the first geometrical mapping function determined by the mechanical structure of the hydraulic support; Defined as time The displacement of the column cylinder; Defined as time The displacement of the lifting cylinder.

[0047] The controller defines the pitch angle of the hydraulic support. Displacement of the column cylinder and displacement of the lifting cylinder The functional relationship. Hydraulic support pitch angle. The function expression is: ; In the formula, Defined as time The pitch angle of the hydraulic support; Defined as the second geometric mapping function determined by the mechanical structure of the hydraulic support.

[0048] To achieve speed and attitude control during the hydraulic support lifting process, the controller modulates the aforementioned top beam height function expression and pitch angle function expression with respect to time. Differential calculations are performed to establish a system of coupled differential equations relating the cylinder's actuation speed to the rate of change of the support's state. The controller calculates the rate of change of the top beam height. The expression is: ; In the formula, Defined as the rate of change of the top beam height over time; Defined as the first geometric mapping function Partial derivative with respect to the displacement of the column cylinder; Defined as the instantaneous speed of the column cylinder; Defined as the first geometric mapping function Partial derivative with respect to the displacement of the lifting cylinder; Defined as the instantaneous speed of the lifting cylinder.

[0049] The rate of change of the support pitch angle calculated by the controller The expression is: ; In the formula, Defined as the rate of change of the support pitch angle over time; Defined as the second geometric mapping function Partial derivative with respect to the displacement of the column cylinder; Defined as the second geometric mapping function Partial derivative with respect to the displacement of the lifting cylinder.

[0050] The controller receives preset hydraulic support lifting process parameters, which include the target height trajectory curve of the top beam, the target bottom landing curve of the base, and the allowable attitude change range. Based on the hydraulic support lifting process parameters and the aforementioned coupled differential equations, the controller calculates the target velocities of the column cylinder and the bottom-lifting cylinder required to maintain the target trajectory using an inverse kinematics algorithm. The controller outputs the calculated target velocities of the column cylinders. With the target speed of the lifting cylinder and set the target speed of the column cylinder. With the target speed of the lifting cylinder This serves as input data for the target traffic calculation process.

[0051] After completing the target velocity calculation step, the controller proceeds to the target flow rate reference generation step. The controller determines the hydraulic action direction of the column cylinder and the base cylinder based on the hydraulic support lifting process requirements. During the hydraulic support lifting stage, the column cylinder extends to lift the top beam, and hydraulic oil enters the rodless chamber of the column cylinder. The base cylinder retracts to adjust the base posture, and hydraulic oil flows out from the return chamber of the base cylinder.

[0052] The effective area of ​​the rodless chamber of the column cylinder calculated in the preceding steps is called by the controller. Target speed of column cylinder The controller is based on the effective area of ​​the rodless chamber of the column cylinder. Target speed of column cylinder Calculate the target flow rate of the column cylinder Target flow rate of column cylinder The calculation formula is: ; In the formula, Defined as time The target fluid inlet flow rate for the column cylinder; Defined as the effective area of ​​the rodless chamber of the column cylinder; Defined as time The target speed of the column cylinder.

[0053] The controller calls the effective area of ​​the bottom-lifting cylinder return oil chamber calculated in the preceding steps. With the target speed of the lifting cylinder The controller is based on the effective area of ​​the return oil chamber of the lifting cylinder. With the target speed of the lifting cylinder Calculate the target flow rate of the bottom-lifting cylinder Target flow rate of the lifting cylinder The calculation formula is: ; In the formula, Defined as time The target return fluid flow rate of the lifting cylinder; Defined as the effective area of ​​the oil return chamber of the bottom-lifting cylinder. Defined as time The target speed of the lifting cylinder.

[0054] The controller will calculate the target flow rate of the column cylinder. With the target flow rate of the bottom lifting cylinder Set as the system flow control benchmark. The controller will set the target flow rate of the column cylinder. With the target flow rate of the bottom lifting cylinder The data is transmitted to the feedforward control module and the fuzzy PID feedback control module to generate subsequent valve control commands.

[0055] See attached document Figure 2 The controller executes the feedforward control branch design steps in a composite control strategy based on feedforward and fuzzy PID. The controller utilizes the feedforward control branch to improve the response speed of the hydraulic support lifting control system, enabling it to quickly track flow demand in the absence of external disturbances. The controller receives the target flow rates of the column cylinder and the bottom-lifting cylinder calculated in the previous steps. The controller's internal storage unit pre-stores flow characteristic data of the electro-hydraulic control valve assembly, which describes the nonlinear mapping relationship between the valve opening and the flow rate.

[0056] The controller uses the flow characteristic data of the electro-hydraulic control valve assembly to construct a reverse valve port flow model. Based on the input target flow rate, the controller uses the reverse valve port flow model to calculate the basic valve port opening required to maintain the target flow rate. The controller then calculates the feedforward valve control opening command. Feedforward valve opening command The calculation formula is: ; In the formula, Defined as time Valve opening feedforward command; Defined as the reverse valve orifice flow model, the reverse valve orifice flow model is the inverse function of the valve orifice flow characteristic curve of the electro-hydraulic control valve group; Defined as time The target traffic.

[0057] The controller performs feedforward calculations for both the column cylinder and the bottom-lifting cylinder. The controller then sets the target flow rate for the column cylinder. As target traffic Substituting the values ​​into the formula for calculating the feedforward valve opening command, the feedforward valve control command for the column cylinder is calculated. The controller will then control the target flow rate of the lifting cylinder. As target traffic Substituting the values ​​into the formula for calculating the feedforward valve opening command, the feedforward valve control command for the bottom-lifting cylinder is calculated. The controller transmits the calculated feedforward valve control commands for the column cylinder and the bottom-lifting cylinder to the final valve control command synthesis stage. The feedforward valve control command serves as the open-loop basic control quantity to drive the electro-hydraulic control valve group to operate.

[0058] See attached document Figure 2 The controller executes the fuzzy PID feedback controller design steps in a composite control strategy based on feedforward and fuzzy PID. The controller utilizes the fuzzy PID feedback control loop to eliminate model uncertainty errors and external disturbance errors during the hydraulic support lifting process. The controller acquires the actual flow rates of the column cylinders and the bottom-lifting cylinders through flow sensors or differential pressure flow estimation modules located on the hydraulic support. The controller acquires the actual pitch angle of the hydraulic support through tilt sensors located on the hydraulic support.

[0059] The controller defines the logic for calculating flow error. The controller calculates the flow error. Flow error The calculation formula is: ; In the formula, Defined as time Flow error; Defined as time The target traffic; Defined as time The actual traffic.

[0060] The controller defines the logic for calculating attitude error. The controller calculates the attitude error. Attitude error The calculation formula is: ; In the formula, Defined as time The attitude error; Defined as time The target pitch angle; Defined as time The actual pitch angle.

[0061] The controller constructs a fuzzy inference system. The fuzzy inference system receives traffic errors. Flow error change rate and attitude error As an input variable: Rate of change of flow error. For flow error Regarding time The derivative of the PID controller. The controller's internal storage unit pre-stores a fuzzy rule table, which defines the fuzzy logic mapping relationship between input variables and PID controller parameter adjustments. The controller adjusts the proportional gain of the PID controller online through fuzzy inference operations. Integral coefficient and differential coefficients .

[0062] The controller calculates the feedback control quantity based on the adjusted PID controller parameters. Feedback control quantity The calculation formula is: ; In the formula, Defined as time Feedback control quantity; Defined as the proportional coefficient of the output of the fuzzy inference system; Defined as time Flow error; Defined as the integral coefficient output by the fuzzy inference system; Defined as the integral of flow error over time; Defined as the differential coefficient of the output of the fuzzy inference system; Defined as time The rate of change of flow error. The controller will calculate the feedback control quantity. The data is then transmitted to the final valve control command synthesis stage.

[0063] See attached document Figure 2 The controller performs the final valve control command synthesis and execution steps in the composite control strategy based on feedforward and fuzzy PID. The controller receives the feedforward valve opening command from the feedforward control branch and the feedback control quantity from the fuzzy PID feedback controller. The controller uses a superposition algorithm to synthesize the final control command applied to the electro-hydraulic control valve assembly.

[0064] The controller calculates the final valve control command. Final valve control command The calculation formula is: ; In the formula, Defined as time The final valve control command; Defined as time Valve opening feedforward command; Defined as time Feedback control quantity.

[0065] The controller will ultimately issue valve control commands. The data is transmitted to the electro-hydraulic control valve assembly drive circuit. The electro-hydraulic control valve assembly drive circuit then executes the final valve control command. The system generates a corresponding drive current signal or pulse width modulation signal. This drive current signal or pulse width modulation signal drives the electromagnet of the electro-hydraulic control valve assembly. The electromagnet drives the valve core of the electro-hydraulic control valve assembly to displace. This valve core displacement changes the flow cross-sectional area of ​​the valve orifice. The electro-hydraulic control valve assembly adjusts the hydraulic oil flow to the column cylinder or the lifting cylinder by changing the flow cross-sectional area of ​​the valve orifice. The controller adjusts the hydraulic oil flow to make the actual flow rate of the column cylinder approach the target flow rate, and to make the actual flow rate of the lifting cylinder approach the target flow rate, thereby controlling the hydraulic support to maintain the preset posture and complete the lifting action.

[0066] See attached document Figure 2 The controller executes the adjacent support synchronization error monitoring step in the coordinated control and anomaly correction of grouped supports. The controller monitors the lifting status of multiple hydraulic supports in the longwall mining face, and defines the hydraulic support currently performing the lifting action as the [number missing]. Hydraulic supports, defined and the first The hydraulic support adjacent to the first hydraulic support is the first Erect a hydraulic support. The controller obtains the data via a data communication network. The displacement of the hydraulic support column cylinder and the first The displacement of the hydraulic support column cylinder. The controller obtains the... The attitude angle of the hydraulic support.

[0067] Controller calculates the first Hydraulic support and the first The synchronization error between the hydraulic supports is calculated. In the synchronization monitoring mode based on the column stroke, the controller calculates the synchronization error. Synchronization error The calculation formula is: ; In the formula, Defined as time No. Synchronization error of hydraulic supports; Defined as time No. Displacement of the hydraulic cylinder of the support column; Defined as time No. The displacement of the hydraulic cylinder of the support column.

[0068] In the synchronous monitoring mode based on the support posture, the controller calculates the synchronization error. Synchronization error The calculation formula is: ; In the formula, Defined as time No. Synchronization error of hydraulic supports; Defined as time No. The pitch angle of the hydraulic support; Defined as time The reference pitch angle. The controller will calculate the synchronization error. The data is transmitted to the coordinated adjustment logic module, which then adjusts it based on the synchronization error. For the The flow command of the hydraulic support is corrected.

[0069] See attached document Figure 2 The controller executes the coordinated adjustment logic steps in the group support coordinated control and anomaly correction. The controller receives the synchronization error calculated in the previous steps. The controller's internal storage unit has a preset set of synchronization error thresholds. The controller will synchronize the error. The absolute value and the synchronization error threshold Compare and determine.

[0070] When synchronization error The absolute value is less than the synchronization error threshold. At this time, the controller maintains the current final valve control command. Unchanged. When synchronization error Greater than the synchronization error threshold When, it indicates the first The movement of the hydraulic support is ahead of the first The hydraulic support is erected, and the controller generates a deceleration correction coefficient. The controller uses the deceleration correction coefficient to reduce the first... Final valve control command for hydraulic support The value of , thereby reducing the first The flow rate of the hydraulic cylinder in the support column. When synchronization error... Less than the negative synchronization error threshold When, it indicates the first The movement of the hydraulic support lags behind the first The hydraulic support is erected, and the controller generates an acceleration correction factor. The controller uses the acceleration correction factor to increase the first... Final valve control command for hydraulic support The value of , thereby increasing the number of The flow rate of the hydraulic cylinder in the column of the hydraulic support.

[0071] While performing synchronous control, the controller also executes attitude-priority correction logic based on the coordination of the column and bottom lifting actions. The controller monitors the actual lifting speed of the column cylinder in real time. With respect to the actual retraction speed of the lifting cylinder The controller calculates the speed ratio between the column cylinder and the bottom-lifting cylinder. Speed ​​ratio The calculation formula is: ; In the formula, Defined as time The speed ratio; Defined as time The actual lifting speed of the column cylinder; Defined as time The actual retraction speed of the lifting cylinder.

[0072] The controller's internal storage unit is set with a speed ratio safety threshold. The controller determines the speed ratio. Is it less than the speed ratio safety threshold? If the speed is higher than Less than the speed ratio safety threshold This indicates that the retraction action of the lifting cylinder was too rapid, and the hydraulic support had a tendency to lift the rear end of the base too high, causing the front end of the top beam to sag. The controller forcibly limits the valve opening of the lifting cylinder by reducing the final valve control command of the lifting cylinder. Reduce the retraction speed of the bottom-lifting hydraulic cylinder. until the speed is greater than Return to the allowable range.

[0073] The controller simultaneously monitors attitude error The controller sets attitude limit thresholds. When attitude error The absolute value exceeds the attitude limit threshold. At this time, the controller triggers the attitude priority correction mode. In attitude priority correction mode, the controller pauses synchronization error. The controller's adjustment function prioritizes adjusting the hydraulic flow rate of the column cylinder to correct the pitch angle of the hydraulic support until the attitude error is corrected. The absolute value is less than the attitude limit threshold. After completing the correction, the controller resumes its synchronization error monitoring and speed ratio monitoring functions.

[0074] See attached document Figure 2 The controller executes the lifting end determination and steady-state control steps in the coordinated control and anomaly correction of the grouped supports. The controller continuously monitors the displacement of the column cylinders throughout the entire hydraulic support lifting process. Displacement of the lifting cylinder and the pitch angle of the hydraulic support The controller's internal storage unit contains a set of parameters for determining the termination of the lifting action. This set of parameters includes the target stroke of the column cylinder. Target stroke of the lifting cylinder Allowable error in positioning of the lifting cylinder Minimum allowable pitch angle and maximum permissible pitch angle .

[0075] The controller performs multi-parameter AND logic operations to determine whether the lifting action is complete. The controller constructs a lifting end logic expression. The lifting end logic expression is: ; In the formula, Defined as the logic state value for the end of the lifting process, when A value of true indicates that the termination condition is met; Defined as time Displacement of the column cylinder; Defined as the target stroke of the column cylinder; Defined as the logical AND operator; Defined as time The displacement of the lifting cylinder; Defined as the target stroke of the lifting cylinder; Defined as the allowable error in the positioning of the lifting cylinder; Defined as time The pitch angle of the hydraulic support; Defined as the minimum permissible pitch angle; Defined as the maximum permissible pitch angle.

[0076] When the lifting operation is complete, the logic state value is... When the value is false, the controller maintains a composite control strategy based on feedforward and fuzzy PID, and continues to output the final valve control command. The electro-hydraulic control valve assembly is activated. The logic state value is as follows: When the lifting mechanism ends... When true, the controller determines that the hydraulic support lifting action is complete and triggers the valve smooth closing logic. The controller no longer calculates the control quantity based on flow error and attitude error; instead, it uses the final valve control command at the current moment. Based on this, the final valve control command is gradually reduced according to a preset linear decay slope. The value.

[0077] The controller calculates the commands during the valve closing process. The final valve control command during the valve closing process. The calculation formula is: ; In the formula, Defined as time The final valve control command; Defined as the logic state value of the lifting end The moment it becomes real; Defined as time The final valve control command value at that time; Defined as the duration of the valve orifice closing process; This indicates that the valve port is completely closed.

[0078] When time Exceed At that time, the controller outputs the final valve control command. When the pressure is zero, the electro-hydraulic control valve assembly is completely closed. The inlet and return circuits of the column cylinder and the bottom-lifting cylinder are cut off, and the hydraulic support enters a steady-state support mode. In steady-state support mode, the controller stops outputting active control commands, but continues to monitor the column cylinder pressure and the hydraulic support posture to ensure the support stability of the hydraulic support during the working face advancement process.

Claims

1. A hydraulic support lifting control method based on flow ratio and attitude feedback, characterized in that, Includes the following steps: S1. The controller establishes a physical parameter model of the hydraulic support. Based on the hydraulic support lifting process parameters and kinematic coupling model, the controller calculates the target flow rate of the column cylinder and the target flow rate of the bottom lifting cylinder. S2. The controller executes a composite control strategy based on feedforward and fuzzy PID. The controller generates a feedforward valve opening command based on the target flow rate of the column cylinder and the target flow rate of the bottom lifting cylinder, and generates a feedback control quantity based on the real-time status data collected by the sensor. The controller then synthesizes the final valve control command and drives the electro-hydraulic control valve group to move. S3. The controller performs coordinated control and anomaly correction of the group of supports. During the process of driving the electro-hydraulic control valve group to move, the controller monitors the synchronization error between adjacent hydraulic supports and corrects the final valve control command based on the synchronization error. The controller monitors the speed coordination status of the column cylinder and the bottom lifting cylinder and performs attitude priority correction. The corrected final valve control command is used to continuously drive the hydraulic support to move. S4. The controller performs the lifting frame completion judgment and steady-state control. The controller collects the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle that change under the final valve control command in real time. Based on the column cylinder displacement, bottom lifting cylinder displacement and hydraulic support pitch angle, the controller determines whether the lifting frame action is completed. When the lifting frame action is completed, the controller executes the valve port smooth closing logic.

2. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S1, the specific steps for the controller to establish the physical parameter model of the hydraulic support include: The controller determines the effective area of ​​the rodless chamber of the column cylinder based on the cylinder diameter. The controller determines the effective area of ​​the rod chamber of the column cylinder based on the cylinder diameter and rod diameter of the column cylinder. The controller determines the effective area of ​​the extension chamber of the lifting cylinder based on the cylinder diameter of the lifting cylinder; The controller determines the effective area of ​​the oil return chamber of the lifting cylinder based on the cylinder diameter and rod diameter of the lifting cylinder; The controller transmits the effective area of ​​the rodless chamber of the column cylinder, the effective area of ​​the rod chamber of the column cylinder, the effective area of ​​the extension chamber of the bottom-lifting cylinder, and the effective area of ​​the return chamber of the bottom-lifting cylinder to the target flow calculation stage.

3. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 2, characterized in that, In step S1, the specific steps by which the controller calculates the target flow rates of the column cylinder and the bottom-lifting cylinder based on the hydraulic support lifting process parameters and the kinematic coupling model include: The controller constructs a description of the geometric constraint relationship between the height of the hydraulic support top beam and the pitch angle of the hydraulic support as a function of the displacement of the column cylinder and the displacement of the bottom lifting cylinder. The controller performs a time-dependent differential operation on the geometric constraints to establish a set of coupled differential equations relating the cylinder's movement speed to the rate of change of the support's state. The controller uses the inverse kinematics algorithm to solve the coupled differential equations based on the target height trajectory curve of the top beam, the target bottoming curve of the base, and the allowable attitude change range, to obtain the target speed of the column cylinder and the target speed of the bottom lifting cylinder.

4. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 3, characterized in that, The specific steps for the controller to calculate the target flow rates of the column cylinder and the bottom-lifting cylinder also include: The controller calculates the target flow rate of the column cylinder based on the effective area of ​​the rodless chamber of the column cylinder and the target speed of the column cylinder. The controller calculates the target flow rate of the lifting cylinder based on the effective area of ​​the return oil chamber of the lifting cylinder and the target speed of the lifting cylinder; The controller sets the target flow rate of the column cylinder and the target flow rate of the bottom lifting cylinder as the flow control reference.

5. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S2, the specific steps for the controller to generate the feedforward valve opening command include: The controller calls the pre-stored flow characteristic data of the electro-hydraulic control valve group to construct a reverse valve port flow model, which is an inverse function of the flow characteristic curve of the electro-hydraulic control valve group. The controller takes the target flow rate of the column cylinder as input and substitutes it into the flow rate model of the reverse valve port to calculate the feedforward valve control command of the column cylinder. The controller takes the target flow rate of the lifting cylinder as input and substitutes it into the flow rate model of the reverse valve port to calculate the feedforward valve control command of the lifting cylinder. The controller transmits the feedforward valve control command of the column cylinder and the feedforward valve control command of the bottom lifting cylinder as the feedforward valve control opening command to the final valve control command synthesis stage.

6. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S2, the specific steps for the controller to generate the feedback control quantity include: The controller calculates the flow error based on the target flow rate and the actual flow rate of the column cylinder, and calculates the flow error change rate based on the flow error. The controller calculates the attitude error based on the target pitch angle and the actual pitch angle; The controller constructs a fuzzy inference system, which receives the flow error, the rate of change of the flow error, and the attitude error as input variables. The controller uses the fuzzy inference system to adjust the proportional coefficient, integral coefficient, and derivative coefficient of the PID controller online. The controller calculates the feedback control quantity based on the adjusted proportional coefficient, integral coefficient, and derivative coefficient.

7. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S3, the specific steps for the controller to monitor the synchronization error between adjacent hydraulic supports include: The controller defines the hydraulic support currently performing the lifting action as the first one. Hydraulic support frame, defined as described in the first... The hydraulic support adjacent to the first hydraulic support is the first Erect hydraulic supports; In the synchronous monitoring mode based on column travel, the controller, according to the first... The displacement of the column cylinder of the hydraulic support is related to the first The synchronization error is calculated based on the displacement of the hydraulic cylinder of the support column. In the synchronous monitoring mode based on the support posture, the controller, according to the first... The synchronization error is calculated by comparing the pitch angle of the hydraulic support with the reference pitch angle. In step S3, the specific steps for the controller to correct the final valve control command based on the synchronization error include: The controller compares the absolute value of the synchronization error with a preset synchronization error threshold to determine the result. When the synchronization error is greater than the synchronization error threshold, the controller generates a deceleration correction coefficient to reduce the first... The value of the final valve control command for the hydraulic support; When the synchronization error is less than the negative synchronization error threshold, the controller generates an acceleration correction coefficient that increases the first... The value of the final valve control command for the hydraulic support.

8. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S3, the specific steps for the controller to monitor the speed coordination state and perform attitude-priority correction include: The controller calculates the speed ratio based on the actual lifting speed of the column cylinder and the actual retraction speed of the bottom-lifting cylinder. The controller determines whether the speed ratio is less than the speed ratio safety threshold. If the speed ratio is less than the speed ratio safety threshold, the controller reduces the final valve control command for the bottom lifting cylinder. The controller monitors the attitude error. When the absolute value of the attitude error exceeds the attitude limit threshold, the controller triggers the attitude priority correction mode. The controller suspends the adjustment function of the synchronization error and prioritizes adjusting the fluid flow rate of the column cylinder.

9. The hydraulic support lifting control method based on flow ratio and attitude feedback according to claim 1, characterized in that, In step S4, the specific steps for the controller to execute the lifting end determination and valve port smooth closing logic include: The controller determines whether the displacement of the column cylinder is greater than or equal to the target stroke of the column cylinder, whether the absolute value of the difference between the displacement of the bottom lifting cylinder and the target stroke of the bottom lifting cylinder is less than or equal to the allowable error of the bottom lifting cylinder in place, and whether the pitch angle of the hydraulic support is between the minimum allowable pitch angle and the maximum allowable pitch angle. When the above judgment conditions are met simultaneously, the controller determines that the lifting end logic state value is true; When the lifting frame ends, the logic state value is true. The controller uses the current final valve control command as a reference and gradually reduces the value of the final valve control command according to a preset linear decay slope until the final valve control command is zero.

10. A hydraulic support lifting control device based on flow ratio and attitude feedback, characterized in that, The hydraulic support lifting control method based on flow ratio and attitude feedback, as described in any one of claims 1-9, comprises: The liquid supply calculation module is used to calculate the effective working area of ​​the column cylinder and the bottom lifting cylinder based on the pre-stored geometric structural parameters, and transmit the effective working area to the target flow calculation link to generate the flow control benchmark. The feedforward control module is used to receive the flow control reference and calculate the feedforward valve opening command by combining it with the pre-stored flow characteristic data of the electro-hydraulic control valve group. The fuzzy PID feedback control module is used to receive real-time status data collected by the sensor group and calculate the feedback control quantity based on the fuzzy inference system. The controller is used to synthesize the feedforward valve opening command and the feedback control quantity into the final valve control command; The coordinated adjustment logic module is used to receive the synchronization error between adjacent hydraulic supports and generate a correction coefficient based on the synchronization error to correct the final valve control command. The electro-hydraulic control valve assembly is used to respond to the final valve control command output by the controller and drive the column cylinder and the bottom lifting cylinder to move.

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