Adaptive thrust allocation control method for high frequency force loaded actuators

Abstract

The application discloses a self-adaptive thrust distribution control method of a high-frequency force loading actuator and belongs to the technical field of mechatronic integrated control. The hydraulic cylinder and the permanent magnet linear synchronous motor are coaxially integrated as a force loading execution unit, the hydraulic system provides low-frequency large loading force, and the motor provides high-frequency force response, and the output forces of the two are mechanically superposed and act on the same load. A thrust distribution control scheme is provided: a feedforward decoupling strategy is designed to enable the hydraulic controller to independently track the total force command and avoid the motor from interfering with the hydraulic circuit in a fast dynamic mode; a compensation mechanism based on error recursion is designed to enable the motor to automatically bear transient high-frequency load according to real-time total force error. Adaptive backstepping control technology is adopted in the two subsystems to compensate for parameter perturbation, unmodeled dynamics and external disturbances in real time through online parameter estimation. The method enables the hybrid actuator to simultaneously have large output capacity and high dynamic response characteristics, and realizes accurate tracking of the total output force on the expected command.

Description

Technical Field

[0001] This invention belongs to the field of force loading and electromechanical-hydraulic integrated control technology, specifically relating to an adaptive thrust distribution control method for a high-frequency force loading actuator. Background Technology

[0002] Force loading technology is a key method for performance verification and quality assessment in fields such as aerospace, high-end equipment manufacturing, and structural fatigue testing. Electro-hydraulic servo loading systems, due to their high power density and large output, have long been the standard industrial solution. However, hydraulic systems are constrained by physical characteristics such as fluid compressibility, valve nonlinearity, and frictional hysteresis, resulting in limited dynamic response bandwidth, making it difficult to meet the simulation requirements of modern high-precision equipment for high-frequency, transient loads. Although advanced control strategies such as adaptive robust control and nonlinear disturbance observation exist, none have been able to overcome the dynamic performance bottleneck of hydraulic systems at the actuator level.

[0003] Permanent magnet linear synchronous motors (PMLSMs) have the advantages of no transmission backlash, fast response, and high precision, making them particularly suitable for high-frequency, small-amplitude force loading scenarios. However, due to limitations in heat accumulation and the risk of permanent magnet demagnetization, the continuous output capacity of PMLSMs is far lower than that of hydraulic cylinders of the same volume, making it difficult to independently undertake high-power, long-term loading tasks.

[0004] In recent years, the idea of ​​coaxially integrating hydraulic cylinders and PMLSMs to form hybrid force loading actuators has attracted attention. This configuration retains the high output advantage of hydraulic systems while introducing the high dynamic compensation capability of PMLSMs, theoretically enabling wide-bandwidth, high-precision force control. However, the two sub-actuators differ significantly in dynamic characteristics, nonlinearity, and bandwidth. Directly superimposing the output force will lead to control loop coupling, deterioration of system stability, and even instability of the hydraulic subsystem or motor overload. How to achieve dynamic decoupling at the control level and rationally allocate thrust according to their respective advantages is the core bottleneck in the engineering application of hybrid loading systems. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of existing single actuators that cannot simultaneously achieve high load capacity and high dynamic response. Addressing issues such as dynamic coupling, unreasonable thrust distribution, and strong parameter uncertainty in coaxial hydraulic-PMLSM hybrid force loading systems, it provides an adaptive thrust distribution control method for a high-frequency force loading actuator. This method achieves dynamic decoupling, intelligent force distribution, and parameter self-adaptation, enabling the hybrid actuator to simultaneously possess wide-bandwidth response and high output capacity. The high-frequency force loading actuator proposed in this invention comprises a hydraulic cylinder and a permanent magnet linear synchronous motor, mechanically coaxially connected, with the output force acting on the same load and directly superimposed.

[0006] The technical solution of the present invention is as follows: An adaptive thrust distribution control method for a high-frequency force loading actuator, wherein the high-frequency force loading actuator is coaxially integrated with a hydraulic cylinder and a permanent magnet linear synchronous motor (PMLSM). Specifically, the hydraulic cylinder adopts a double-rod symmetrical hydraulic cylinder structure. The cylinder body and the stator of the PMLSM are rigidly connected and fixed on the same frame. The piston rod of the hydraulic cylinder and the mover of the motor are mechanically coaxially connected through a rigid coupling. The output forces are directly superimposed along the same axis and act together on the load end. The hydraulic cylinder utilizes its high output force characteristics to handle low-frequency steady-state loads, while the PMLSM provides high-frequency transient compensation with its high dynamic response capability. The two complement each other, thereby achieving wide-bandwidth, high-precision force loading control. The control method includes the following steps: S1: Establish dynamic models of the hydraulic subsystem and motor subsystem of the high-frequency force loading actuator, and design adaptive controllers for each.

[0007] S1.1: Establish a dynamic model of the hydraulic subsystem. Taking into account the continuity of hydraulic cylinder flow, the linearized flow characteristics of the servo valve, and the dynamic coupling caused by piston movement, the hydraulic pressure... The dynamic behavior can be summarized by the following first-order differential equation: in, Indicates the output force of the hydraulic cylinder. Indicates hydraulic pressure The first derivative with respect to time, i.e., the rate of change of hydraulic pressure; Indicates the servo valve control voltage; The equivalent damping coefficient is related to leakage, oil compressibility, etc. This represents the control gain, which is related to the valve's flow gain, piston area, etc. This represents lumped disturbances, including flow rate changes caused by piston motion, unmodeled dynamics, and external disturbances.

[0008] S1.2: Design an adaptive controller for the hydraulic subsystem. This is to achieve the desired hydraulic pressure. Precise tracking, defining the tracking error of hydraulic force. Based on Lyapunov stability theory, the following adaptive backstepping control law is designed. : in, Indicates the controller gain. , , They represent , , The online estimate is obtained. The parameter adaptive law is designed as follows: in, , , These represent the adaptive parameters. , , Adaptive gain; , , These represent the adaptive parameters. , , The first derivative with respect to time. Under the action of the above control law and adaptive law, it can be guaranteed that the tracking error of the hydraulic subsystem asymptotically converges to zero, and all closed-loop signals are bounded.

[0009] S1.3: Establish a dynamic model of the permanent magnet linear synchronous motor subsystem of the high-frequency force loading actuator. This invention employs a surface-mounted permanent magnet linear synchronous motor, characterized by... shaft and Since the inductances of the shafts are equal, the thrust is solely due to... The shaft current determines the torque component, and there is no reluctance torque component. Therefore, this model is no longer applicable to embedded motors with unequal inductance. Based on the characteristics of surface-mounted permanent magnet linear synchronous motors, a model is established... - Dynamic model of current in a rotating coordinate system: in, , They represent shaft and Stator voltage of the shaft, , They represent shaft and Stator current of the shaft; , , These represent the nominal values ​​of stator resistance, inductance, and permanent magnet flux linkage, respectively. Indicates the velocity of the mover. Indicates the polar distance; , They represent shaft and The lumped disturbances of the axis include parameter uncertainties (such as changes in resistance, inductance, and flux linkage) and unmodeled dynamics.

[0010] motor output thrust Depend on Shaft current determines: in, This refers to the actual permanent magnet flux linkage (which includes uncertainties).

[0011] S1.4: Design an adaptive current loop controller for the motor subsystem. To achieve accurate current tracking, a... Maximum torque-to-current ratio control strategy. Definition shaft and Tracking error of shaft current , ,in, express Shaft reference current, for The shaft reference current is given by the subsequent thrust distribution step. An adaptive current controller is designed based on the Lyapunov method, with the following control law: in, , They represent shaft and The controller gain of the axis; , , , They represent , , , The estimated value; , They represent , The first derivative with respect to time. The corresponding adaptive law is designed as follows: in, , , , These represent the adaptive parameters. , , , Adaptive gain; , , , These represent the adaptive parameters. , , , The first derivative with respect to time. This controller guarantees that the current tracking error asymptotically converges to zero, and that all signals in the closed-loop system are uniformly bounded.

[0012] The models of the two subsystems and the design of adaptive controllers have been established, providing a foundation for subsequent thrust allocation strategies. The specific parameter tuning methods and stability conclusions for each controller have been clarified in the aforementioned design, and their effectiveness will be further verified through experiments in specific implementations.

[0013] S2: Construct a thrust allocation strategy based on feedforward decoupling and error compensation.

[0014] The total output force of the high-frequency force loading actuator For hydraulic cylinder output force thrust of permanent magnet linear synchronous motor The sum of The two are mechanically coaxially connected and act on the same load.

[0015] Based on the design of adaptive controllers for the two subsystems, a thrust distribution strategy is proposed to achieve coordinated control of the hydraulic cylinder and the permanent magnet linear synchronous motor. The core idea of ​​this strategy is that the hydraulic cylinder independently tracks the total force command to bear the steady-state large load, while the motor provides dynamic compensation based on the real-time total force error to achieve high-frequency response. The two achieve natural division of labor through feedforward decoupling and error compensation mechanisms.

[0016] S2.1: The hydraulic controller employs a corrected tracking error. To prevent the rapid dynamics of the motor from adversely interfering with the slower-responding hydraulic circuit, the tracking error of the hydraulic controller is... Reconstructed as: in, This indicates the desired total force command.

[0017] After adopting the above error definition, the feedback loop of the hydraulic controller no longer includes the motor output force. This means that the hydraulic subsystem independently tracks the total force command, and its control behavior is not directly affected by the dynamic changes of the motor, thereby achieving dynamic decoupling of the two subsystems at the control level. The hydraulic controller still uses the adaptive control law (Equation (2) and Equation (3)) designed in S1.2, based on the hydraulic pressure tracking error. Calculate the servo valve control voltage .

[0018] S2.2: Error compensation mechanism for the motor circuit. The motor subsystem does not directly track the total force command, but provides dynamic compensation based on the real-time total force tracking error. Motor desired thrust. Recursively generated using the following incremental method: in, This represents the discrete control cycle number. This represents the measured total output force. The physical meaning of this recursive strategy is: when the total output force... Lagging behind expected instructions At that time, that is When the expected thrust of the motor increases, the motor outputs force quickly to compensate for the error; when the total output force exceeds the expected command, the expected thrust of the motor decreases and actively unloads; when the total output force accurately tracks the command, the error is zero, and the expected thrust of the motor remains at the current value. If the system is in a steady state and the hydraulic cylinder has borne the full load, the motor thrust will automatically return to near zero.

[0019] Will Converted to thrust constant Shaft reference current and order Shaft reference current ,Will , By inputting the motor adaptive current controller designed in S1.4 (Equations (6) and (7)), the motor thrust can be accurately tracked.

[0020] S2.3: Overall Architecture of the Thrust Distribution Strategy. Based on the above design, the workflow of the entire thrust distribution control strategy can be summarized as follows: 1) Decoupled feedback: The hydraulic controller uses a corrected hydraulic pressure tracking error. It independently tracks total force commands and is unaffected by motor dynamics. 2) Error compensation: The motor recursively generates the desired thrust based on the total force error, achieving dynamic "compensation"; 3) Parameter adaptation: The controllers of both subsystems maintain online parameter estimation to compensate for model uncertainties and external disturbances in real time; 4) Command limiting protection: for the motor's desired thrust Set reasonable limits (such as not exceeding 70%~80% of the motor's rated thrust) to leave margin for the motor's dynamic response and avoid overload.

[0021] This strategy eliminates the need for manual weight allocation or mode switching. The two subsystems automatically divide their tasks based on their dynamic characteristics: the hydraulic cylinder handles the large-amplitude, low-frequency base load, while the motor handles the transient, high-frequency compensation load. Since the hydraulic control loop is decoupled, the motor's rapid response does not compromise the stability of the hydraulic system; furthermore, the motor's compensation mechanism ensures that the total output force accurately tracks the desired command. The overall stability of this strategy is guaranteed by the independent stability of each subsystem's controller, and the recursive compensation mechanism only involves linear combinations of bounded signals, without introducing additional instabilities.

[0022] S3: Stability analysis and proof.

[0023] S3.1: For the hydraulic subsystem, select a candidate Lyapunov function that includes tracking error and parameter estimation error: in, For the composite Lyapunov function of the hydraulic subsystem; , , They represent , , The estimation error.

[0024] By taking the system dynamics derivative as shown in formula (1) and substituting it into the control law shown in formula (2) and the adaptive law shown in formula (3), we can obtain: in, Let be the first derivative of the Lyapunov function of the hydraulic subsystem with respect to time. Therefore, we know... Monotonically non-increasing, therefore , , , Both are bounded. Furthermore, for Points , This represents the space of square-integrable functions, which implies the tracking error. The square of is integrable in time, and this can be proven by the system dynamics. Bounded. According to Barbalat's lemma, we have... That is, the hydraulic subsystem can asymptotically track the desired force command.

[0025] S3.2: For the motor subsystem, select candidate Lyapunov functions: in, For the composite Lyapunov function of the motor subsystem; , , , They represent , , , The estimation error. Taking the system dynamics derivative as shown in formula (4), and substituting it into the control law shown in formula (6) and the adaptive law shown in formula (7), we can obtain: in, Let be the first derivative of the Lyapunov function of the motor subsystem with respect to time. Therefore, we know... Since it is monotonically non-increasing, all error signals are bounded. Integrating, we get... And it can be proven by dynamics. , Bounded. Applying Barbalat's lemma, we get... , This means that the current can accurately track the reference command, thereby increasing the motor thrust. It can accurately track the desired thrust.

[0026] S3.3: Stability of the hybrid system.

[0027] As can be seen from S3.1 Define the total output force. error According to the continuous form of the motor recursive command shown in formula (9) and in S3.2 right The asymptotic tracking can be deduced Furthermore, the boundedness of all closed-loop signals is directly guaranteed by the stability of each subsystem and the boundedness of the thrust distribution strategy. Therefore, the control strategy designed in this invention can guarantee the global stability of the high-frequency force loading system and achieve asymptotically accurate tracking of the total output force to the desired command.

[0028] The beneficial effects of this invention are as follows: This invention combines the high output capacity of a hydraulic cylinder with the high dynamic response characteristics of a permanent magnet linear synchronous motor. By constructing a thrust distribution strategy based on feedforward decoupling and error compensation, it achieves complementary advantages and coordinated control between the two types of actuators. The hydraulic controller independently tracks the total force command by correcting the tracking error, fundamentally cutting off the reverse coupling of the motor's rapid dynamics to the hydraulic circuit, significantly enhancing the system's robustness. The motor recursively generates compensation commands based on the total force error, automatically undertaking transient high-frequency loads without manual allocation or mode switching. Both subsystems are designed with adaptive controllers with online parameter estimation, capable of real-time compensation for parameter perturbations, unmodeled dynamics, and external disturbances, ensuring asymptotic convergence of the tracking error. Compared with existing control schemes, this invention significantly improves dynamic tracking accuracy and transient response speed, achieving a unity of high-frequency force loading and large-amplitude output capability, providing an effective engineering solution for wideband, high-load-force loading requirements. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a high-frequency force loading actuator for a hydraulic-permanent magnet linear synchronous motor; in the diagram, 1 is a permanent magnet linear synchronous motor, 2 is a hydraulic cylinder, 3 is a force sensor, and 4 is a servo valve. Figure 2 Control flowchart for adaptive force allocation control strategy; Figure 3This is a schematic diagram of the experimental platform architecture for the hydraulic-PMLSM high-frequency force loading actuator. Figure 4 This is a comparison diagram of the tracking curves of the embodiment of the present invention and the comparative method under sinusoidal force command; Figure 5 This is a comparison chart of the response curves of the embodiments of the present invention and the comparative method under a step force command; Figure 6 This is a diagram showing the instantaneous force distribution between the hydraulic cylinder and the motor during sinusoidal tracking, according to an embodiment of the present invention. Figure 7 This is a diagram showing the dynamic force distribution between the hydraulic cylinder and the motor during a step response in an embodiment of the present invention. Detailed Implementation

[0030] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0031] To verify the performance of the adaptive thrust distribution control strategy proposed in this invention, this embodiment relies on a hydraulic-PMLSM high-frequency force loading actuator experimental platform. The structure of the high-frequency force loading actuator is as follows: Figure 1 As shown, the experimental platform's architecture consists of the following components: Figure 3 As shown, the overall flow of the control strategy is as follows: Figure 2 As shown in the figure. A system mechanism model was built based on actual physical parameters. The usage process and control effect of the invention were demonstrated through experiments. The force tracking performance and thrust distribution results of the system are shown in the figure. The specific implementation process is as follows: S1: Physical parameters. The controlled object used in the experiment of this invention is a coaxial integrated hydraulic cylinder-PMLSM hybrid high-frequency force loading actuator. The hydraulic subsystem is a double-acting single-rod hydraulic cylinder with an effective piston area of... Total control volume The working stroke is 360mm, the system working pressure is 21 MPa, and the hydraulic power source is a fixed displacement piston pump with a rated pressure of 35 MPa and a rated flow rate of 12 L / min. The motor subsystem uses a surface-mounted permanent magnet linear synchronous motor, model ZKM200-B8, with a stator resistance of... Phase inductance Permanent magnet magnetic flux polar distance Continuous thrust 5840 N, thrust constant The total output force is measured by a force sensor with a range of ±15kN and an accuracy of 0.05% FS, while the piston displacement is monitored by a grating ruler with a resolution of 1 μm. The control algorithm runs on an NI Linux RT real-time embedded controller with a sampling and control cycle of 1 kHz, and communicates with the servo driver and I / O modules via an EtherCAT bus.

[0032] S2: Reference Trajectory and Initial Value Selection. To verify the tracking performance of the control strategy, two types of reference trajectories were selected for the experiment. The first type was a low-frequency sinusoidal force command: The first type, with a frequency of 0.1 Hz, a bias of 9 kN, and an amplitude of 3 kN, is used to evaluate steady-state tracking accuracy. The second type is a step force command. A step jump from 10 kN to 15 kN was used to evaluate the transient response speed. The initial values ​​of the controller's internal state were selected as follows: , , , , , , Initial value of expected thrust of motor .

[0033] S3: Controller Parameter Design. The hydraulic subsystem controller parameters are: proportional gain. Adaptive gain , , The parameters for the motor current controller are: Axis gain , Axis gain Adaptive gain , , , In the thrust distribution strategy, a limit is set on the desired thrust of the motor. This allows for a margin in the motor's dynamic response while preventing overload.

[0034] S4: Comparison of Strategies and Performance Indicators. To verify the effectiveness of this invention, three control strategies were compared on the same experimental platform: PID (PID control only for the hydraulic cylinder), ABC (adaptive backstepping control only for the hydraulic cylinder), and ABC-C (the thrust distribution control strategy proposed in this invention). Maximum absolute error (MAX) and root mean square error (RMSE) were used as quantitative evaluation indicators for tracking performance.

[0035] S5: Experimental Results and Analysis. In the sinusoidal tracking experiment, such as... Figure 4 As shown, the maximum error of the PID scheme is 1671 N, the maximum error of the ABC scheme is 1341 N, while the maximum error of the ABC-C strategy scheme of this invention is only 493 N, which is a reduction of 70.5% and 63.2% compared to PID and ABC, respectively. In the step response experiment, as... Figure 5 As shown, the PID scheme has a settling time of 2.920s, the ABC scheme has a settling time of 1.800s, and the ABC-C strategy scheme of this invention has a settling time of 0.900s, which is 69.2% and 50.0% shorter than PID and ABC respectively, and the overshoot is less than 1% for all of them. Figure 6 The instantaneous force distribution between the hydraulic cylinder and the motor during sinusoidal tracking is demonstrated. The motor responds quickly in each cycle of the command fluctuation, providing high-frequency compensation force, while the hydraulic cylinder outputs steady-state basic force smoothly. The two form a division of labor mode of "fast compensation and slow bearing". Figure 7 The dynamic force distribution between the hydraulic cylinder and the motor during the step response is demonstrated. After the step command is applied, the motor quickly outputs force to compensate for the response lag of the hydraulic cylinder. Subsequently, the output of the hydraulic cylinder gradually increases to the steady-state value, while the output of the motor decreases and approaches zero, achieving a smooth transition from transient compensation to steady-state connection.

[0036] The above experiments illustrate the specific implementation process of this invention, verifying the effectiveness of the designed adaptive thrust distribution control method. The accompanying figures show the control process and thrust distribution results of the experimental case. Experimental results demonstrate that the control strategy proposed in this invention enables the hydraulic-PMLSM high-frequency force loading actuator to achieve high-precision force tracking under conditions of parameter uncertainty and dynamic coupling, possessing both high output capacity and high dynamic response characteristics, thus providing an effective engineering solution for wideband, high-load-force loading requirements.

Claims

1. An adaptive thrust distribution control method for a high-frequency force loading actuator, wherein the high-frequency force loading actuator is coaxially integrated with a hydraulic cylinder and a permanent magnet linear synchronous motor (PMLSM). The hydraulic cylinder adopts a double-rod symmetrical hydraulic cylinder structure. The cylinder body and the stator of the PMLSM are rigidly connected and fixed on the same frame. The piston rod of the hydraulic cylinder and the mover of the motor are mechanically coaxially connected through a rigid coupling. The output forces are directly superimposed along the same axis and act together on the load end. The method is characterized in that... The control method includes the following steps: S1: Establish dynamic models of the hydraulic subsystem and motor subsystem of the high-frequency force loading actuator, and design adaptive controllers for each. S1.1: Establish a dynamic model of the hydraulic subsystem; comprehensively consider the continuity of hydraulic cylinder flow, the linearized flow characteristics of the servo valve, and the dynamic coupling caused by piston movement, and integrate the hydraulic pressure... The dynamic behavior can be summarized by the following first-order differential equation: in, Indicates the output force of the hydraulic cylinder. Indicates hydraulic pressure The first derivative with respect to time, i.e., the rate of change of hydraulic pressure; Indicates the control voltage of the servo valve; This is the equivalent damping coefficient, which is related to leakage and oil compressibility; This represents the control gain, which is related to the valve's flow gain and piston area. This represents lumped disturbance, which includes flow changes caused by piston motion, unmodeled dynamics, and external disturbances. S1.2: Design an adaptive controller for the hydraulic subsystem; to achieve the desired hydraulic pressure. Precise tracking, defining the tracking error of hydraulic force. Based on Lyapunov stability theory, the following adaptive backstepping control law is designed. : in, Indicates the controller gain. , , They represent , , Online estimates; the parameter adaptive law is designed as follows: in, , , These represent the adaptive parameters. , , Adaptive gain; , , These represent the adaptive parameters. , , The first derivative with respect to time; S1.3: Establish a dynamic model of the permanent magnet linear synchronous motor subsystem of the high-frequency force loading actuator; using a surface-mounted permanent magnet linear synchronous motor, establish its dynamic model in... - Dynamic model of current in a rotating coordinate system: in, , They represent shaft and Stator voltage of the shaft, , They represent shaft and Stator current of the shaft; , , These represent the nominal values ​​of stator resistance, inductance, and permanent magnet flux linkage, respectively. Indicates the velocity of the mover. Indicates the polar distance; , They represent shaft and Lumped disturbances of the axis include parameter uncertainties and unmodeled dynamics; motor output thrust Depend on Shaft current determines: in, For actual permanent magnet flux linkage; S1.4: Design an adaptive current loop controller for the motor subsystem; to achieve accurate current tracking, adopt... Maximum torque-to-current ratio control strategy; definition shaft and Tracking error of shaft current , ,in, express Shaft reference current, for The shaft reference current is given by the subsequent thrust distribution step; an adaptive current controller is designed based on the Lyapunov method, and the control law is as follows: in, , They represent shaft and The controller gain of the axis; , , , They represent , , , The estimated value; , They represent , The first derivative with respect to time; the corresponding adaptive law is designed as follows: in, , , , These represent the adaptive parameters. , , , Adaptive gain; , , , These represent the adaptive parameters. , , , The first derivative with respect to time; S2: Construct a thrust allocation strategy based on feedforward decoupling and error compensation; The total output force of the high-frequency force loading actuator For hydraulic cylinder output force thrust of permanent magnet linear synchronous motor The sum of The two are mechanically coaxially connected and act on the same load; Based on the design of adaptive controllers for the two subsystems, a thrust distribution strategy is proposed to achieve coordinated control of the hydraulic cylinder and the permanent magnet linear synchronous motor. The core idea of ​​this strategy is that the hydraulic cylinder independently tracks the total force command to bear the steady-state large load, while the motor provides dynamic compensation based on the real-time total force error to achieve high-frequency response. The two achieve natural division of labor through feedforward decoupling and error compensation mechanisms.

2. The adaptive thrust distribution control method for a high-frequency force loading actuator according to claim 1, characterized in that, S2 is as follows: S2.1: The hydraulic controller employs a corrected tracking error; to prevent the rapid dynamics of the motor from causing adverse interference to the slower-responding hydraulic circuit, the tracking error of the hydraulic controller is... Reconstructed as: in, Indicates the desired total force command; The hydraulic controller adopts the adaptive control law designed in S1.2, based on the hydraulic pressure tracking error. Calculate the servo valve control voltage ; S2.2: Error compensation mechanism for the motor circuit; the motor subsystem does not directly track the total force command, but provides dynamic compensation based on the real-time total force tracking error; the motor's desired thrust. Recursively generated using the following incremental method: in, This represents the discrete control cycle number. This is the measured value of the total output force; Will Converted to thrust constant Shaft reference current and order Shaft reference current ,Will , The motor adaptive current controller designed with input S1.4 achieves precise tracking of motor thrust; S2.3: Overall architecture of the thrust allocation strategy; the workflow of the entire thrust allocation control strategy can be summarized as follows: 1) Decoupled feedback: The hydraulic controller uses a corrected hydraulic pressure tracking error. It independently tracks total force commands and is unaffected by motor dynamics. 2) Error compensation: The motor recursively generates the desired thrust based on the total force error, achieving dynamic "error compensation"; 3) Parameter adaptation: The controllers of both subsystems maintain online parameter estimation and compensate for model uncertainties and external disturbances in real time; 4) Command limiting protection: for the motor's desired thrust Set reasonable limits to allow for a margin in the motor's dynamic response, while avoiding overload.

3. The adaptive thrust distribution control method for a high-frequency force loading actuator according to claim 1, characterized in that, The control method further includes: S3: Stability analysis and proof; S3.1: For the hydraulic subsystem, select a candidate Lyapunov function that includes tracking error and parameter estimation error: in, For the composite Lyapunov function of the hydraulic subsystem; , , They represent , , The estimation error; Differentiating the system dynamics as shown in formula (1), and substituting it into the control law shown in formula (2) and the adaptive law shown in formula (3), we get: in, The first derivative of the Lyapunov function of the hydraulic subsystem with respect to time; for Points , Let the space of square-integrable functions be represented; according to Barbalat's lemma, we have That is, the hydraulic subsystem can asymptotically track the desired force command; S3.2: For the motor subsystem, select candidate Lyapunov functions: in, For the composite Lyapunov function of the motor subsystem; , , , They represent , , , The estimation error; taking the system dynamics derivative along formula (4), and substituting it into the control law shown in formula (6) and the adaptive law shown in formula (7), we get: in, Let Lyapunov's function of the motor subsystem be the first derivative with respect to time; integrating, we get... And by dynamic certificate , Bounded; applying Barbalat's lemma, we get , This means that the current can accurately track the reference command, thereby increasing the motor thrust. It can accurately track the desired thrust; S3.3: Stability of the hybrid system; From S3.1 Define the total output force. error According to the continuous form of the motor recursive command shown in formula (9) and in S3.2 right The gradual tracking, pushing .

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