MRAC-TVC-based frequency band expansion type composite vibration table control system and method

Abstract

The invention discloses a frequency band extension type composite vibration table control system and method based on MRAC-TVC, and the system and method are applied to a frequency band extension type composite vibration table which comprises a lower-layer low-frequency vibration table, a low-frequency long-stroke servo actuator, an upper-layer high-frequency vibration table and a high-frequency short-stroke servo actuator. The control system comprises a lower-layer low-frequency table control system and an upper-layer high-frequency table control system, the lower-layer low-frequency table control system comprises a lower-layer low-frequency vibration table, a low-frequency long-stroke servo actuator, a low-frequency table inner closed-loop subsystem and a low-frequency table outer closed-loop subsystem; the upper-layer high-frequency table control system comprises an upper-layer high-frequency vibration table, a high-frequency short-stroke servo actuator, a high-frequency table inner closed-loop subsystem and a high-frequency table outer closed-loop subsystem. According to the invention, not only is the robustness of the earthquake simulation vibration table system to cope with the load change under the influence of the dynamic response of the experimental structure increased, but also the experimental structure can be prevented from being damaged too early.

Description

Technical Field

[0001] The present invention relates to the technical field of earthquake simulation, and in particular to a frequency band expansion type composite vibration table control system and method based on MRAC-TVC. Background Art

[0002] Earthquakes are a natural phenomenon that is difficult to predict. The damage to engineering structures caused by earthquakes is an important cause of loss of life and property. In order to ensure that engineering structures or buildings have good reliability and the required service life, the vibration table test is currently the most widely used and direct test method. This test method is to fix the specimen on the vibration table body and stimulate the table body to move through the actuator to reproduce the specified vibration state. This test method has great advantages in studying structural dynamic characteristics, seismic performance and structural failure mechanism.

[0003] With the development of building structure systems, the vibration table test needs to adapt to the requirements of different specimens. On the one hand, it needs to have the ability to simulate the dynamic response of structures such as buildings and bridges under low-frequency and long-period earthquakes. On the other hand, it needs to have the ability to simulate the dynamic response of structures such as dams and nuclear power plants under high-frequency and short-stroke earthquakes. This puts forward the requirements of long-stroke and wide-band loading for the vibration table. However, the bandwidth of traditional large vibration tables is usually low while moving in long strokes. In view of this situation, a new type of vibration table structure is used to install the upper high-frequency table on the lower low-frequency table to form a composite vibration table that contains both wide-band actuators and long-stroke actuators, namely, a frequency-band extension composite vibration table. However, in the actual vibration process, the frequency-band extension composite vibration table will produce large tracking errors due to the coupling effect of the upper high-frequency table and the lower low-frequency table and the different bandwidths, thereby affecting the control effect. It is necessary to design its control algorithm to achieve long-stroke and wide-band excitation of the vibration table.

[0004] Therefore, it is an urgent problem for those skilled in the art to propose a frequency band expansion composite vibration table control system and method based on MRAC-TVC to solve the difficulties existing in the prior art. Summary of the invention

[0005] The purpose of the present invention is to provide a frequency band extended composite vibration table control system and method based on MRAC-TVC, which not only increases the robustness of the earthquake simulation vibration table system to cope with load changes when it is affected by the dynamic response of the experimental structure, but also avoids premature damage to the experimental structure.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A frequency band extension composite vibration table control system based on MRAC-TVC is applied to the frequency band extension composite vibration table, the frequency band extension composite vibration table comprises a lower layer low frequency vibration table, a low frequency long stroke servo actuator, an upper layer high frequency vibration table and a high frequency short stroke servo actuator, and the control system comprises a lower layer low frequency table control system and an upper layer high frequency table control system;

[0008] Among them, the lower low-frequency table control system includes the lower low-frequency vibration table, the low-frequency long-stroke servo actuator, the low-frequency table internal closed-loop subsystem and the low-frequency table external closed-loop subsystem; the upper high-frequency table control system includes the upper high-frequency vibration table, the high-frequency short-stroke servo actuator, the high-frequency table internal closed-loop subsystem and the high-frequency table external closed-loop subsystem;

[0009] The low-frequency platform external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the low-frequency long-stroke servo actuator, and the low-frequency platform internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the low-frequency long-stroke servo actuator; the high-frequency platform external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the high-frequency short-stroke servo actuator, and the high-frequency platform internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the high-frequency short-stroke servo actuator.

[0010] Preferably, an acceleration sensor is installed on the lower low-frequency vibration table to record the acceleration response of each degree of freedom of the lower low-frequency vibration table relative to the ground. The displacement signal fed back by the lower actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the lower low-frequency vibration table relative to the ground, and the velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

[0011] Preferably, an acceleration sensor is installed on the upper high-frequency vibration table to record the acceleration response of each degree of freedom of the upper high-frequency vibration table relative to the ground. The displacement signal fed back by the upper actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the upper high-frequency vibration table relative to the ground, and the velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

[0012] A frequency band expansion type composite vibration table control method based on MRAC-TVC is applied to any of the frequency band expansion type composite vibration table control systems based on MRAC-TVC described above, comprising the following steps:

[0013] S1. Set a target seismic wave, and obtain a low-frequency seismic wave time domain signal and a high-frequency seismic wave time domain signal after frequency division of the target seismic wave;

[0014] S2, inputting the low-frequency and high-frequency seismic wave time domain signals into the lower low-frequency station external closed-loop subsystem and the upper high-frequency station external closed-loop subsystem respectively;

[0015] S3, after the feedforward and feedback control of the outer closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform, the input signal of the inner closed-loop subsystem is obtained, which is input into the inner closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform, and then the control signal for driving the low-frequency long-stroke servo actuator and the high-frequency short-stroke servo actuator is obtained. The control signal drives each actuator to move respectively through the degree of freedom decomposition matrix, and finally realizes the upper high-frequency vibration table and the lower low-frequency vibration table to perform three-way six-degree-of-freedom movement;

[0016] S4. The position signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained respectively after degree of freedom synthesis through the preset actuator displacement sensor, the acceleration signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained through the preset table body acceleration sensor, and the velocity signals of each degree of freedom are calculated and fed back to the control systems of the upper high-frequency vibration table and the lower low-frequency vibration table respectively, so that the frequency band extended composite vibration table can reproduce the target seismic wave signal through the control system.

[0017] Preferably, the method for frequency domain division of the target seismic wave in S1 adopts FFT / IFFT method, and the frequency division frequency is within the frequency range achievable by the lower low-frequency vibration table.

[0018] Preferably, the design of the MRAC controller in the S3 low-frequency station closed-loop subsystem and the high-frequency station closed-loop subsystem specifically includes the following steps:

[0019] S301, using the vibration table and the test specimen as the controlled objects of the MRAC controller, and using the low-frequency seismic wave signal and the high-frequency seismic wave signal as the output signals of the inner closed-loop reference model of the lower low-frequency table and the upper high-frequency table respectively;

[0020] S302, the state equation of the inner closed-loop reference model is obtained by identifying the inner closed-loop subsystem:

[0021]

[0022] Among them, x m (t) is the reference model state vector, u m (t) is the input signal of the reference model, which is the acceleration time history record of the seismic wave in the earthquake simulation shaking table system, and y m (t) is the output state vector of the reference model, A m is the state matrix of the reference model, B m and C m are the input and output matrices of the reference model, respectively;

[0023] S303, adopting MRAC control based on state variables, using adaptive rate to adjust state feedback controller parameters and feedforward controller parameters online; selecting Lyapunov function as:

[0024]

[0025] Among them, e x (t) is the generalized error signal, P is a symmetric positive definite matrix, and represents a symmetric positive definite constant matrix of appropriate dimension, is the parameter error vector of the state feedback controller, is the parameter error vector of the state feedforward controller;

[0026] For any symmetric positive definite matrix Q, there exists a symmetric positive definite matrix P that satisfies the Lyapunov equation:

[0027] A m T P+PA m =-Q

[0028] The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows:

[0029]

[0030] Among them, K p [e y (t), t] is the m×n-dimensional time-varying feedback gain matrix, K u [e y (t), t] is the m×m-dimensional parameter-varying feedforward gain matrix, Γ p and Γ u is a symmetric positive definite constant matrix with appropriate dimensions, is the feedforward gain at a certain moment, e y (t) is the acceleration tracking error, y z (τ) is the output state vector of the controlled object, u m (τ) is the control signal of the model reference adaptive controller, K p (0), K u (0) are the feedback and feedforward control parameters at the initial moment respectively.

[0031] Preferably, the MRAC adaptive rate derivation process is as follows:

[0032] The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows:

[0033]

[0034] Among them, x s (τ) is the n-dimensional state vector of the table and the test structure in the earthquake simulation shaking table system; the reference model, i.e., the transfer function of the shaking table, is constructed m (s) = C m (sI-A m ) -1 B m is a strictly positive real function, then according to the Kalman-Yakubovich lemma, the MRAC adaptation rate is simplified to:

[0035]

[0036] In the frequency band extension composite vibration table system, the desired output signal is the acceleration signal of the upper high-frequency table and the lower low-frequency table. The inner closed-loop subsystem adjusts the control parameters in real time according to the acceleration errors of the upper high-frequency table and the lower low-frequency table, and the outer closed-loop subsystem reproduces the velocity signal or displacement signal. At this time, the parameters of the MRAC controller are adjusted as follows:

[0037]

[0038] A non-transitory computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, a frequency band extension composite vibration table control method based on MRAC-TVC as described above is implemented.

[0039] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0040] (1) The present invention introduces an MRAC controller, which adjusts the parameters of the controller online in real time through adaptive rules, and does not need to obtain an accurate mathematical model of the controlled object in advance. This not only increases the robustness of the earthquake simulation shaking table system to cope with load changes when it is affected by the dynamic response of the experimental structure, but also avoids premature damage to the experimental structure.

[0041] (2) The present invention introduces an outer closed-loop TVC controller so that the inner closed-loop MRAC controller only needs to perform real-time control parameter adjustments based on the acceleration errors of the upper high-frequency station and the lower low-frequency station, which can effectively reduce the order of the MRAC controller parameters and improve ease of use.

[0042] (3) The present invention is directed to the structural form of a band-extended composite vibration table, and adopts a MRAC-TVC joint control method for the upper high-frequency table and the lower low-frequency table, respectively, so that they can accurately reproduce the target wide-band seismic wave signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0044] Figure 1 A schematic diagram of the mechanical structure of a frequency band expansion composite vibration table to which the control algorithm of the present invention is applied;

[0045] Figure 2 A schematic diagram of a control system for a frequency band expansion composite vibration table to which the control algorithm of the present invention is applied;

[0046] Figure 3 A control block diagram of a frequency band expansion composite vibration table based on MRAC-TVC of the present invention;

[0047] Figure 4 This is the structure diagram of the MRAC system based on state variables. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] Since the present invention is based on the control method of the original vibration table control system, the mechanical structure of the traditional vibration table is only briefly described. Figure 1 As shown, according to the large load test frequency and area expandable modular vibration table disclosed in patent CN211784164U, a frequency band expansion composite vibration table is constructed, the lower low-frequency table body is equipped with horizontal low-frequency long-stroke servo actuators on the sides, and the bottom is equipped with vertical low-frequency long-stroke servo actuators; the upper high-frequency table body is equipped with horizontal high-frequency short-stroke servo actuators on the sides, and the bottom is equipped with vertical high-frequency short-stroke servo actuators. By inputting frequency division excitation to the multi-channel motion controller, the lower low-frequency table body performs long-stroke low-frequency motion, and the upper high-frequency table body performs short-stroke high-frequency motion relative to the lower low-frequency table body, so that the acceleration response of the upper high-frequency table body contains both high-frequency and low-frequency components of seismic waves, and finally accurately reproduces wider frequency seismic waves.

[0051] like Figure 2 As shown, the present invention provides a frequency band expansion type composite vibration table control system based on MRAC-TVC, which is composed of a host computer / controller and a driving device to respectively constitute a lower-layer low-frequency table control system and an upper-layer high-frequency table control system, thereby realizing the control of the frequency band expansion type composite vibration table (controlled object).

[0052] Applied to a frequency band extension composite vibration table, the frequency band extension composite vibration table includes a lower low-frequency vibration table, a low-frequency long-stroke servo actuator, an upper high-frequency vibration table and a high-frequency short-stroke servo actuator, and the control system includes a lower low-frequency table control system and an upper high-frequency table control system;

[0053] Among them, the lower low-frequency table control system includes the lower low-frequency vibration table, the low-frequency long-stroke servo actuator, the low-frequency table internal closed-loop subsystem and the low-frequency table external closed-loop subsystem; the upper high-frequency table control system includes the upper high-frequency vibration table, the high-frequency short-stroke servo actuator, the high-frequency table internal closed-loop subsystem and the high-frequency table external closed-loop subsystem;

[0054] The low-frequency platform external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the long-stroke servo actuator, and the low-frequency platform internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the long-stroke servo actuator; the high-frequency platform external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the short-stroke servo actuator, and the high-frequency platform internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the short-stroke servo actuator. The corresponding I / O ports inside the lower-level low-frequency platform control system and the upper-level high-frequency platform control system are used for input / output, allowing operators to build a frequency-band extended composite vibration platform control system based on the original vibration platform control system.

[0055] Furthermore, an acceleration sensor is installed on the lower low-frequency vibration table to record the acceleration response of each degree of freedom of the lower low-frequency vibration table relative to the ground. The displacement signal fed back by the lower actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the lower low-frequency vibration table relative to the ground. The velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

[0056] Furthermore, an acceleration sensor is installed on the lower low-frequency vibration table to record the acceleration response of each degree of freedom of the lower low-frequency vibration table relative to the ground. The displacement signal fed back by the lower actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the lower low-frequency vibration table relative to the ground, and the velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

[0057] A frequency band extension composite vibration table control method based on MRAC-TVC, such as Figure 3As shown, the MRAC-TVC-based frequency band extension composite vibration table control system applied to any of the above items comprises the following steps:

[0058] S1. Set a target seismic wave, and obtain a low-frequency seismic wave time domain signal and a high-frequency seismic wave time domain signal after frequency division of the target seismic wave;

[0059] S2, inputting the low-frequency and high-frequency seismic wave time domain signals into the lower low-frequency station external closed-loop subsystem and the upper high-frequency station external closed-loop subsystem respectively;

[0060] S3, after the outer closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform is feedforward and feedback controlled, the input signal of the inner closed-loop subsystem is obtained, which is input into the inner closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform, and then the control signal for driving the low-frequency long-stroke servo actuator and the high-frequency short-stroke servo actuator is obtained. The control signal drives each actuator to move respectively through the degree of freedom decomposition matrix, and finally realizes the upper high-frequency vibration table and the lower low-frequency vibration table to perform three-way six-degree-of-freedom motion;

[0061] S4. The position signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained respectively after degree of freedom synthesis through the preset actuator displacement sensor, the acceleration signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained through the preset table body acceleration sensor, and the velocity signals of each degree of freedom are calculated and fed back to the control systems of the upper high-frequency vibration table and the lower low-frequency vibration table respectively, so that the frequency band extended composite vibration table can reproduce the target seismic wave signal through the control system.

[0062] Furthermore, the method of frequency domain division of the target seismic wave in S1 adopts the FFT / IFFT method, and the frequency division frequency is within the frequency range that can be achieved by the lower low-frequency vibration table. The low-frequency and high-frequency seismic wave time domain signals are respectively input into the outer closed-loop subsystem of the lower low-frequency table and the outer closed-loop subsystem of the upper high-frequency table. After the feedforward and feedback control of the outer closed-loop subsystem of the lower low-frequency table and the upper high-frequency table, the input signal of the inner closed-loop subsystem is obtained, and finally the control signal for driving the low-frequency long-stroke servo actuator and the high-frequency short-stroke servo actuator is obtained to drive the upper high-frequency table and the lower low-frequency table to move respectively. The position, velocity and acceleration signals of the upper high-frequency table and the lower low-frequency table are obtained through sensors and fed back to their respective control systems, so that the frequency band expansion composite vibration table reproduces the target seismic wave signal.

[0063] Furthermore, the design of MRAC controllers in the S3 low-frequency station closed-loop subsystem and high-frequency station closed-loop subsystem is as follows: Figure 4 As shown, the specific steps include:

[0064] S301, the vibration table and the test specimen are used as the controlled objects of the MRAC controller. In addition, for the vibration table system, the expected output of the controlled object is very clear, which is the expected reproducible seismic wave time history record, so the low-frequency seismic wave signal and the high-frequency seismic wave signal are used as the output signals of the inner closed-loop reference model of the low-frequency table and the high-frequency table respectively.

[0065] S302, the state equation of the inner closed-loop reference model is obtained by identifying the inner closed-loop subsystem (no precise model is required):

[0066]

[0067] Among them, x m (t) is the reference model state vector, u m (t) is the input signal of the reference model, which is the acceleration time history record of the seismic wave in the earthquake simulation shaking table system, and y m (t) is the output state vector of the reference model, A m is the state matrix of the reference model, B m and C m are the input and output matrices of the reference model, respectively;

[0068] S303, adopting MRAC control based on state variables, using adaptive rate to adjust state feedback controller parameters and feedforward controller parameters online; selecting Lyapunov function as:

[0069]

[0070] Among them, e x (t) is the generalized error signal, P is a symmetric positive definite matrix, and represents a symmetric positive definite constant matrix of appropriate dimension, is the parameter error vector of the state feedback controller, is the parameter error vector of the state feedforward controller;

[0071] To ensure the stable convergence of the system, for any symmetric positive definite matrix Q, there exists a symmetric positive definite matrix P that satisfies the Lyapunov equation:

[0072] A m T P+PA m =-Q

[0073] The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows:

[0074]

[0075] Among them, K p [e y (t), t] is the m×n-dimensional time-varying feedback gain matrix, K u [e y (t), t] is the m×m-dimensional parameter-varying feedforward gain matrix, Γ p , Γ u To represent a symmetric positive definite constant matrix of appropriate dimensions, is the feedforward gain at a certain moment, e y (t) is the acceleration tracking error, y z (τ) is the output state vector of the controlled object, u m (τ) is the control signal of the model reference adaptive controller, K p (0), K u (0) are the feedback and feedforward control parameters at the initial moment respectively.

[0076] Furthermore, the MRAC adaptation rate derivation process is as follows:

[0077] The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows:

[0078]

[0079] Among them, x s (τ) is the n-dimensional state vector of the table and the test structure in the earthquake simulation shaking table system; the reference model, i.e., the transfer function of the shaking table, is constructed m (s) = c m (sI-A m ) -1 B m is a strictly positive real function, then according to the Kalman-Yakubovich lemma, the MRAC adaptation rate is simplified to:

[0080]

[0081] In the frequency band extension composite vibration table system, the desired output signal is the acceleration signal of the upper high-frequency table and the lower low-frequency table. The inner closed-loop subsystem adjusts the control parameters in real time according to the acceleration errors of the upper high-frequency table and the lower low-frequency table, and the outer closed-loop subsystem reproduces the velocity signal or displacement signal, thereby ensuring the accurate reproduction of the target seismic wave. At this time, the parameters of the MRAC controller are adjusted as follows:

[0082]

[0083] A non-transitory computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, a frequency band extension composite vibration table control method based on MRAC-TVC as described above is implemented.

[0084] The MRAC-TVC joint control method combines the MRAC controller with the TVC controller in the traditional earthquake simulation shaker to achieve better control effects. This method can achieve precise control and optimization of the frequency band extended composite shaker system and effectively ensure the stability and robustness of the system.

[0085] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0086] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A frequency band extension composite vibration table control system based on MRAC-TVC, applied to a frequency band extension composite vibration table, the frequency band extension composite vibration table comprises a lower layer low frequency vibration table, a low frequency long stroke servo actuator, an upper layer high frequency vibration table and a high frequency short stroke servo actuator, characterized in that: The control system includes a lower-level low-frequency station control system and an upper-level high-frequency station control system; The lower low-frequency table control system includes a lower low-frequency vibration table, a low-frequency long-stroke servo actuator, a low-frequency table inner closed-loop subsystem and a low-frequency table outer closed-loop subsystem; the upper high-frequency table control system includes an upper high-frequency vibration table, a high-frequency short-stroke servo actuator, a high-frequency table inner closed-loop subsystem and a high-frequency table outer closed-loop subsystem; The low-frequency table external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the low-frequency long-stroke servo actuator, and the low-frequency table internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the low-frequency long-stroke servo actuator; the high-frequency table external closed-loop subsystem is a TVC control system based on the displacement, velocity and acceleration feedback of the high-frequency short-stroke servo actuator, and the high-frequency table internal closed-loop subsystem is an MRAC control system based on the acceleration feedback of the high-frequency short-stroke servo actuator.

2. The MRAC-TVC-based frequency band expansion composite vibration table control system according to claim 1, characterized in that: An acceleration sensor is installed on the lower low-frequency vibration table to record the acceleration response of each degree of freedom of the lower low-frequency vibration table relative to the ground. The displacement signal fed back by the lower actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the lower low-frequency vibration table relative to the ground, and the velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

3. The MRAC-TVC-based frequency band expansion composite vibration table control system according to claim 2, characterized in that: An acceleration sensor is installed on the upper high-frequency vibration table to record the acceleration response of each degree of freedom of the upper high-frequency vibration table relative to the ground. The displacement signal fed back by the upper actuator is passed through the degree of freedom synthesis matrix to obtain the displacement response of each degree of freedom of the upper high-frequency vibration table relative to the ground, and the velocity response of each degree of freedom is obtained by calculating the acceleration and displacement response.

4. A frequency band expansion type composite vibration table control method based on MRAC-TVC, applied to the frequency band expansion type composite vibration table control system based on MRAC-TVC according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1. Set a target seismic wave, and obtain a low-frequency seismic wave time domain signal and a high-frequency seismic wave time domain signal after frequency division of the target seismic wave; S2, inputting the low-frequency and high-frequency seismic wave time domain signals into the lower low-frequency station external closed-loop subsystem and the upper high-frequency station external closed-loop subsystem respectively; S3, after the outer closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform is feedforward and feedback controlled, the input signal of the inner closed-loop subsystem is obtained, which is input into the inner closed-loop subsystem of the lower low-frequency platform and the upper high-frequency platform, thereby obtaining the control signal for driving the low-frequency long-stroke servo actuator and the high-frequency short-stroke servo actuator. The control signal drives each actuator to move respectively through the degree of freedom decomposition matrix, and finally realizes the upper high-frequency vibration platform and the lower low-frequency vibration platform to perform three-way six-degree-of-freedom motion; S4. The position signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained respectively after degree of freedom synthesis through the preset actuator displacement sensor, the acceleration signals of each degree of freedom of the upper high-frequency vibration table and the lower low-frequency vibration table are obtained through the preset table body acceleration sensor, and the velocity signals of each degree of freedom are calculated and fed back to the control systems of the upper high-frequency vibration table and the lower low-frequency vibration table respectively, so that the frequency band extended composite vibration table can reproduce the target seismic wave signal through the control system.

5. The method for controlling a frequency band-extended composite vibration table based on MRAC-TVC according to claim 4, characterized in that: The method for frequency domain division of the target seismic wave in S1 adopts the FFT / IFFT method, and the frequency division frequency is within the frequency range that can be achieved by the lower low-frequency vibration table.

6. The method for controlling a frequency band-extended composite vibration table based on MRAC-TVC according to claim 4, characterized in that: The design of the MRAC controller in the S3 low-frequency station closed-loop subsystem and the high-frequency station closed-loop subsystem specifically includes the following steps: S301, using the vibration table and the test specimen as the controlled objects of the MRAC controller, and using the low-frequency seismic wave signal and the high-frequency seismic wave signal as the output signals of the inner closed-loop reference model of the lower low-frequency table and the upper high-frequency table respectively; S302, the state equation of the inner closed-loop reference model is obtained by identifying the inner closed-loop subsystem: Among them, x m (t) is the reference model state vector, u m (t) is the input signal of the reference model, which is the acceleration time history record of the seismic wave in the earthquake simulation shaking table system, and y m (t) is the output state vector of the reference model, A m is the state matrix of the reference model, B m and C m are the input and output matrices of the reference model, respectively; S303, adopting MRAC control based on state variables, using adaptive rate to adjust state feedback controller parameters and feedforward controller parameters online; selecting Lyapunov function as: Among them, e x (t) is the generalized error signal, P is a symmetric positive definite matrix, and represents a symmetric positive definite constant matrix of appropriate dimension, is the parameter error vector of the state feedback controller, is the parameter error vector of the state feedforward controller; For any symmetric positive definite matrix Q, there exists a symmetric positive definite matrix P that satisfies the Lyapunov equation: A m T P+PA m =-Q The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows: Among them, K p [e y (t), t] is the m×n-dimensional time-varying feedback gain matrix, K u [e y (t), t] is the m×m-dimensional parameter time-varying feedforward gain matrix, and To represent a symmetric positive definite constant matrix of appropriate dimensions, is the feedforward gain at a certain moment, e y (t) is the acceleration tracking error, y z (τ) is the output state vector of the controlled object, u m (τ) is the control signal of the model reference adaptive controller, K p (0), K u (0) are the control parameters of feedback and feedforward at the initial moment respectively.

7. The method for controlling a frequency band-extended composite vibration table based on MRAC-TVC according to claim 6, characterized in that: The MRAC adaptive rate derivation process is as follows: The MRAC adaptive rate used to adjust the error between the output of the controlled object and the output of the reference model and make the dynamic characteristics of the controlled object consistent with the reference model is obtained. The expression is as follows: Among them, x s (τ) is the n-dimensional state vector of the table and the test structure in the earthquake simulation shaking table system; the reference model, i.e., the transfer function of the shaking table, is constructed m (s) = C m (sI-A m ) -1 B m is a strictly positive real function, then according to the Kalman-Yakubovich lemma, the MRAC adaptation rate is simplified to: In the frequency band extension composite vibration table system, the desired output signal is the acceleration signal of the upper high-frequency table and the lower low-frequency table. The inner closed-loop subsystem adjusts the control parameters in real time according to the acceleration errors of the upper high-frequency table and the lower low-frequency table, and the outer closed-loop subsystem reproduces the velocity signal or displacement signal. At this time, the parameters of the MRAC controller are adjusted as follows:

8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for controlling a frequency band-extended composite vibration table based on MRAC-TVC as claimed in any one of claims 4 to 7 is implemented.

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