A frequency division vibration control method applicable to series excitation systems

Abstract

This invention discloses a frequency-division vibration control method suitable for series-type excitation systems, including test parameter setting, system self-testing, transfer function identification, and single-frame periodic cyclic vibration control. The control method fully considers the inability of a single frequency range control mode to guarantee high-precision control for different types of excitation systems with varying frequency characteristics. It divides the entire vibration frequency band into low-frequency and high-frequency intervals, respectively, based on the frequency characteristics of the low-frequency and high-frequency stations. Different transfer function compensation and window compensation techniques are applied to different intervals. Furthermore, effective frames are extracted from the time-domain output signals using a frame extraction method, achieving smooth overlap of the system's time-domain signals. Combining the low-frequency and high-frequency station crossover frequency calculation method, the output signals of the low-frequency and high-frequency stations are superimposed to achieve stable and smooth frequency-division control of complex series-type excitation systems.

Description

Technical Field

[0001] This invention relates to the field of vibration test control technology, and in particular to a frequency division vibration control method applicable to series excitation systems. Background Technology

[0002] With the continuous development of aerospace and military technologies, the requirements for the combat readiness of weapons and equipment are becoming increasingly stringent. To fully simulate complex vibration states under real-world conditions, it is necessary to achieve various complex environment testing capabilities, including: vibration-dynamic centrifugal composite testing, multi-factor composite testing technology, noise and vibration testing technology, multi-axis vibration, and multi-degree-of-freedom vibration environment simulation technology. Traditional vibration testing techniques and single vibration testing techniques, such as using a single electric or hydraulic vibration table for routine product evaluation, are increasingly unable to meet the needs of weapon products for vibration environment assessment and simulation under complex multi-factor conditions. Therefore, to achieve vibration testing technology under the aforementioned complex multi-factor conditions, traditional single electric or hydraulic vibration tables will not meet the testing requirements. A series excitation system needs to be designed, and specific control methods need to be adopted to meet the technical requirements and accuracy of vibration testing under complex multi-factor conditions. For example, in the confined space of a high-dynamic centrifuge and under the limited total load mass of the centrifuge, a wideband excitation system (5Hz~2000Hz) must be installed to achieve a certain magnitude of wideband vibration. While conventional hydraulic vibration tables are relatively small in size and mass, they can only perform vibration in the low-to-mid frequency range (5Hz-250Hz). Electric vibration tables can achieve wide-frequency vibration from 5Hz to 2000Hz, but their size and mass are too large. Neither type of vibration table meets the installation requirements of a centrifuge. Therefore, a wide-frequency vibration system combining a hydraulic vibration table and a piezoelectric exciter in series—a hydraulic-piezoelectric series excitation system—is necessary to achieve the vibration required for the aforementioned test system. However, achieving high-precision frequency division control of the low-frequency hydraulic table and the high-frequency piezoelectric excitation unit remains a significant technical challenge.

[0003] Therefore, it is necessary to develop a frequency division vibration control method suitable for series excitation systems to solve the above problems. Summary of the Invention

[0004] The purpose of this invention is to design a frequency division vibration control method suitable for series excitation systems in order to solve the above problems.

[0005] The present invention achieves the above objectives through the following technical solutions:

[0006] A frequency division vibration control method applicable to a series excitation system includes the following steps:

[0007] S1. Test parameter settings; The test parameters to be set include parameters of the series excitation system, self-test parameters, transfer function identification parameters, window compensation coefficient, and safety parameters;

[0008] S2. System self-test: According to the self-test start voltage, send a pseudo-random signal obtained by broadband powder noise spectrum conversion and gradually increase it until it reaches the self-test level; by detecting the output of the detection system, determine whether the series excitation system is working properly. If it is normal, proceed to the next step; otherwise, end.

[0009] S3. Transfer Function Identification: Based on the identification level set in the series excitation system, the pseudo-random signal obtained by broadband powder noise spectrum conversion is used to identify the transfer function of the series excitation system. During the transfer function identification process, transfer function identification is performed separately for the low-frequency station and the high-frequency station: the identification signal is sent to turn on the low-frequency station drive system and turn off the high-frequency station drive system, thereby completing the transfer function identification of the low-frequency station; conversely, the transfer function identification of the high-frequency station is completed.

[0010] S4. Single-frame periodic cyclic vibration control; S41. First, obtain single-frame data from the vibration controller and perform FFT transformation; S42. Apply a low-frequency window to obtain the low-frequency drive spectrum signal and apply a high-frequency window to obtain the high-frequency drive spectrum signal; S43. Multiply the low-frequency drive spectrum signal by the inverse transfer function of the low-frequency station, and then perform IFFT transformation to obtain the time-domain drive frame signal. Finally, use the frame extraction method to extract the effective frame drive signal and output it to the low-frequency station; S44. Multiply the high-frequency drive spectrum signal by the inverse transfer function of the high-frequency station, and then perform IFFT transformation to obtain the time-domain drive frame signal. Finally, use the frame extraction method to extract the effective frame drive signal and output it to the high-frequency station; S45. This realizes the frequency division control of the series excitation system.

[0011] Specifically, in step S3, the system transfer function identification using the pseudo-random signal obtained by broadband powder noise spectrum conversion includes: using the powder noise pseudo-random signal, multiple transfer function samples in the frequency domain are obtained under frame data shifting mode, and the transfer function of the series excitation system is calculated as follows:

[0012]

[0013] here, Represents m samples The sample in; H m This represents the transfer function for the m-th linear average of m samples, where m is the set number of averages.

[0014] Therefore, the transfer function H of the low-frequency station is calculated respectively. md The transfer function H of the high frequency station mh .

[0015] Furthermore, during the steady-state random vibration test, a step S441 is set between steps S44 and S45. Step S441 includes: using the low-frequency and high-frequency station crossover frequency calculation method to obtain the accurate time-domain frequency division point; connecting the output results of the low-frequency station and the high-frequency station to obtain the acceleration output signal of the series excitation system; combining the single-frame drive signal of the vibration controller to calculate the transfer function of the series excitation system; obtaining the standard normalized transfer function of the series excitation system through the transfer function overlap method; comparing the current system transfer function with the standard normalized transfer function of the series excitation system; and updating the low-frequency window function and high-frequency window function by updating the low-frequency and high-frequency window functions.

[0016] Specifically, in step S4, the frame extraction method includes: extracting the middle segment from a single frame as the number of effective frame points, wherein the formula for calculating the number of effective frame points is as follows:

[0017]

[0018] Where L represents the number of points in a single frame, and N is the number of valid frame points extracted.

[0019] Specifically, in step S441, the method for calculating the low-frequency / high-frequency station crossover frequency includes:

[0020] Using the transfer function H of the obtained low-frequency station md The transfer function H of the high frequency station mh The root mean square ratio A of the input and output signals in the low-frequency station transfer function identification process is used as a reference value; whereby the root mean square ratio A is calculated as follows:

[0021] The normalized value A of the amplitude-frequency response is calculated as follows:

[0022]

[0023] Here, Y rms X represents the root mean square value of the low-frequency station's output signal. rms This represents the root mean square value of the input signal to the low-frequency station;

[0024] In addition, according to the transfer function amplitude-frequency value abs(H) of the low-frequency station md Based on the given upper limit of the low-frequency station frequency, the search amplitude value is approximately equal to... The corresponding frequency value is used as the crossover frequency between the low- and high-frequency stations.

[0025] Specifically, in step S441, the method for obtaining the system standard normalized transfer function includes:

[0026] First, the amplitude frequency value of the system's standard normalized transfer function is set to 1. The phase frequency value of the transfer function is then overlapped based on the crossover frequency, connecting the phase frequency values ​​of the transfer functions from the low-frequency and high-frequency stations. During the overlapping process, a weighted transition overlap is performed 10*ΔfHz to the left and right of the crossover frequency. The overlapping method is as follows:

[0027] Specifically, at positions 10*ΔfHz to the left and right of the crossover frequency, the phase frequency of the low-frequency station is: θ d(-10) ~θ d(0) ~θ d(10) , where θ d(0) The low-frequency phase frequency value at the crossover frequency;

[0028] At points 10*ΔfHz to the left and right of the crossover frequency, the phase frequency of the high-frequency station is: λ g(-10) ~λ g(0) ~λ g(10) , where λ g(0) The phase frequency value of the high-frequency station at the crossover frequency;

[0029] In addition, the parameters of the series excitation system include sampling frequency, number of spectral lines, number of points per frame, system frequency range, and accelerometer sensitivity. Δf represents the frequency resolution, and Δf is calculated as follows:

[0030]

[0031] Where L represents the number of points per frame, f s The sampling frequency;

[0032] Therefore, near the crossover frequency, the phase frequency of the system's standard normalized transfer function is:

[0033]

[0034] Where i = -10, ..., 0, ..., 10; thus, the normalized transfer function of the system is obtained.

[0035] Specifically, in step S441, the method for updating the high and low frequency domain window functions includes:

[0036] In single-frame periodic cyclic vibration control, the system's transfer function is identified using the single-frame input and output signals through a transfer function identification method. Based on the identified system transfer function and the system's standard normalized transfer function, high- and low-frequency domain window functions are obtained; where the high- and low-frequency domain window functions Win... A The calculation is as follows:

[0037]

[0038] Among them, H s This indicates the identified system transmission. This indicates a system standard normalized transfer function;

[0039] Then, using the crossover frequency as the frequency coordinate dividing point, the high and low frequency domain window functions are split into a low-frequency window function Win. d and high-frequency window function Win g The low-frequency window compensation coefficient λ d High frequency λ g Finally, the updated low-frequency window function is obtained. and high-frequency window functions The calculation method is as follows:

[0040]

[0041] Finally, the updated low-frequency window function will be... and high-frequency window functions The single-frame FFT spectrum of the controller drive signal is windowed, and this process is repeated cyclically to complete the frequency division control of the system.

[0042] The beneficial effects of this invention are as follows:

[0043] This invention is not only applicable to high-precision vibration test control of complex series wideband excitation, but also, when conducting steady random vibration tests, it employs a low-to-high frequency crossover frequency calculation method, a system standard normalized transfer function technique, and a high-to-low frequency domain window function update technique, which can effectively improve and obtain a good and flat system amplitude-frequency characteristic.

[0044] This invention's control method fully considers the inability of a single-frequency-range control mode to guarantee high-precision control of different types of excitation systems with varying frequency characteristics. Specifically, it divides the entire vibration frequency band into low-frequency and high-frequency intervals, addressing the frequency characteristics of both low-frequency and high-frequency stations. Different transfer function compensation and window compensation techniques are employed for each interval. Furthermore, effective frames are extracted from the time-domain output signals using a frame extraction method, achieving smooth overlap of the system's time-domain signals. By combining the low-frequency and high-frequency station crossover frequency calculation methods and superimposing the low-frequency and high-frequency station output signals, a smooth and stable frequency-division control of complex series-type excitation systems is achieved. Attached Figure Description

[0045] Figure 1 This is a flowchart of this application. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of 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, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0047] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0048] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0049] In the description of this invention, it should be understood that the terms "upper," "lower," "inner," "outer," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0050] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0051] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connection" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0053] like Figure 1 As shown, a frequency division vibration control method applicable to a series excitation system includes the following steps:

[0054] S1. Test Parameter Settings; The test parameters set include series excitation system parameters, self-test parameters, transfer function identification parameters, window compensation coefficient, and safety parameters; Self-test parameters include initial self-test voltage and self-test level; Transfer function identification parameters include identification level, identification frame count, frequency upper and lower limits of station 1 and station 2; Window compensation coefficient includes compensation parameters for station 1 and station 2, where station 1 and station 2 represent low-frequency station and high-frequency station; Safety parameters include acceleration alarm limit, drive voltage alarm limit, acceleration shutdown limit, and drive voltage shutdown limit.

[0055] The parameters of a series-type excitation system include sampling frequency, number of spectral lines, number of points per frame, system frequency range, and accelerometer sensitivity. Δf represents the frequency resolution, which is calculated as follows:

[0056]

[0057] Where L represents the number of points per frame, f s The sampling frequency;

[0058] S2. System self-test: According to the self-test start voltage, send a pseudo-random signal obtained by broadband powder noise spectrum conversion and gradually increase it until it reaches the self-test level; by detecting the output of the detection system, determine whether the series excitation system is working properly. If it is normal, proceed to the next step; otherwise, end.

[0059] S3. Transfer Function Identification: Based on the identification level set in the series excitation system, the pseudo-random signal obtained by broadband powder noise spectrum conversion is used to identify the transfer function of the series excitation system. During the transfer function identification process, transfer function identification is performed separately for the low-frequency station and the high-frequency station: the identification signal is sent to turn on the low-frequency station drive system and turn off the high-frequency station drive system, thereby completing the transfer function identification of the low-frequency station; conversely, the transfer function identification of the high-frequency station is completed.

[0060] Considering that both the system's input and output signals contain some noise, the directly calculated transfer function curve will not be very smooth. Therefore, a pseudo-random signal obtained through wideband powder noise spectrum conversion is used for system transfer function identification. This includes: using the powder noise pseudo-random signal, multiple transfer function samples in the frequency domain are obtained under frame data shifting. Linear averaging can achieve a better transfer function smoothing effect. The transfer function of the series excitation system is then calculated as follows:

[0061]

[0062] here, Represents m samples The sample in; H m This represents the transfer function for the m-th linear average of m samples, where m is the set number of averages.

[0063] Therefore, the transfer function H of the low-frequency station is calculated respectively.md The transfer function H of the high frequency station mh .

[0064] S4. Single-frame periodic cyclic vibration control; This embodiment proposes to use a hydraulic-piezoelectric series excitation mode to achieve high-precision control for wide-frequency vibration (e.g., 5Hz-2000Hz). Therefore, a hydraulic system is used in the low-frequency range, and a piezoelectric excitation system is used in the high-frequency range to achieve series joint excitation. Based on the system transfer function obtained in step S3, the inverse transfer function of the low-frequency station, the inverse transfer function of the high-frequency station, and the normalized transfer function of the system are obtained, and the initial single-frame drive signal is calculated. Real-time cyclic processing is performed on the single-frame data, completing the following steps within the single-frame time period: S41. First, obtain single-frame data from the vibration controller (obtained by single-frame measurement of the control response signal), and perform FFT transformation; S42. Apply a low-frequency window to obtain the low-frequency drive spectrum signal, and apply a high-frequency window to obtain the high-frequency drive spectrum signal; S43. Multiply the low-frequency drive spectrum signal by the inverse transfer function of the low-frequency station, and then perform IFFT transformation to obtain the time-domain drive frame signal. Finally, use the frame extraction method to extract the effective frame drive signal and output it to the low-frequency station; S44. Multiply the high-frequency drive spectrum signal by the inverse transfer function of the high-frequency station, and then perform IFFT transformation to obtain the time-domain drive frame signal. Finally, use the frame extraction method to extract the effective frame drive signal and output it to the high-frequency station; S45. This realizes the frequency division control of the series-type excitation system.

[0065] When conducting a steady random vibration test, step S441 is set between steps S44 and S45. Step S441 includes: using the low-frequency and high-frequency station crossover frequency calculation method to obtain the accurate time-domain frequency division point; using the output results of the low-frequency station and the high-frequency station in series to obtain the acceleration output signal of the series excitation system; combining the single-frame drive signal of the vibration controller to calculate the transfer function of the series excitation system; obtaining the standard normalized transfer function of the series excitation system through the transfer function overlap method; comparing the current system transfer function with the standard normalized transfer function of the series excitation system; and updating the low-frequency window function and the high-frequency window function by updating the low-frequency and high-frequency window functions.

[0066] The frame extraction method includes extracting the middle segment from a single frame as the effective frame point count. This method effectively avoids the time-domain signal truncation error that occurs during the direct construction of the original signal frames, ensuring smooth time-domain signal splicing of the system. The formula for calculating the effective frame point count is as follows:

[0067]

[0068] Where L represents the number of points in a single frame, and N is the number of valid frame points extracted.

[0069] In step S441, when superimposing low-frequency and high-frequency station signals, to ensure the accuracy of the frequency division point, the crossover frequency between the low-frequency and high-frequency stations needs to be obtained; the calculation method for the low-frequency and high-frequency station crossover frequency includes:

[0070] Using the transfer function H of the obtained low-frequency station md The transfer function H of the high frequency station mh The root mean square ratio A of the input and output signals in the low-frequency station transfer function identification process is used as a reference value; whereby the root mean square ratio A is calculated as follows:

[0071] The normalized value A of the amplitude-frequency response is calculated as follows:

[0072]

[0073] Here, Y rms X represents the root mean square value of the low-frequency station's output signal. rms This represents the root mean square value of the input signal to the low-frequency station;

[0074] In addition, according to the transfer function amplitude-frequency value abs(H) of the low-frequency station md Based on the given upper limit of the low-frequency station frequency, the search amplitude value is approximately equal to... The corresponding frequency value is used as the crossover frequency between the low- and high-frequency stations.

[0075] In step S441, the method for obtaining the system standard normalized transfer function includes:

[0076] By using the transfer function overlap method, the system's standard normalized transfer function can be obtained. First, the amplitude frequency value of the system's standard normalized transfer function is set to 1. The phase frequency value of the transfer function is then overlapped based on the crossover frequency, by overlapping the phase frequency values ​​of the transfer functions from the low-frequency and high-frequency stations. During the overlap process, a weighted transition overlap is performed 10*ΔfHz to the left and right of the crossover frequency. The overlap method is as follows:

[0077] Specifically, at positions 10*ΔfHz to the left and right of the crossover frequency, the phase frequency of the low-frequency station is: θ d(-10) ~θ d(0) ~θ d(10) , where θ d(0) The low-frequency phase frequency value at the crossover frequency;

[0078] At points 10*ΔfHz to the left and right of the crossover frequency, the phase frequency of the high-frequency station is: λ g(-10) ~λ g(0) ~λ g(10) , where λ g(0) The phase frequency value of the high-frequency station at the crossover frequency;

[0079] Therefore, near the crossover frequency, the phase frequency of the system's standard normalized transfer function is:

[0080]

[0081] Where i = -10, ..., 0, ..., 10; thus, the normalized transfer function of the system is obtained.

[0082] In step S441, the method for updating the high and low frequency domain window functions includes:

[0083] In single-frame periodic cyclic vibration control, the system's transfer function H is identified using the single-frame input and output signals through a transfer function identification method. s Based on the identified system transfer function H s With system standard normalized transfer function Win, the high and low frequency domain window function A ; Among them, the high and low frequency domain window function Win A The calculation is as follows:

[0084]

[0085] Among them, H s This indicates the identified system transmission. This indicates a system standard normalized transfer function;

[0086] Then, using the crossover frequency as the frequency coordinate dividing point, the high and low frequency domain window functions are split into a low-frequency window function Win. d and high-frequency window function Win g The low-frequency window compensation coefficient λ d High frequency λ g Finally, the updated low-frequency window function is obtained. and high-frequency window functions The calculation method is as follows:

[0087]

[0088] Finally, the updated low-frequency window function will be... and high-frequency window functions The single-frame FFT spectrum of the controller drive signal is windowed, and this process is repeated cyclically to complete the frequency division control of the system.

[0089] This invention achieves high-precision control over a wide frequency band vibration range. First, a system reference control spectrum is established. Second, the transfer function of the controlled object is identified to obtain the system transfer function, and the inverse transfer function of the low-frequency station, the inverse transfer function of the high-frequency station, and the normalized transfer function of the system are obtained. The initial single-frame drive signal is then calculated. Next, low-frequency and high-frequency window functions are applied to the single-frame control data after FFT transformation, and the corresponding drive spectrum is updated using their respective drive spectra and inverse transfer functions. After IFFT transformation, the effective frames are extracted using frame decimation. Combined with the low- and high-frequency station crossover frequency calculation method, the system standard normalized transfer function is obtained.

[0090] The low-frequency station output signal and the high-frequency station output signal are superimposed onto the system acceleration output signal and compared with the single-frame drive signal of the vibration controller to calculate the system transfer function. Finally, the current system transfer function is compared with the system standard normalized transfer function through the system standard normalized transfer function technique, and the low-frequency window function and high-frequency window function are updated.

[0091] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A frequency-division vibration control method applicable to a series-type excitation system, characterized in that, Including the following steps: S1. Test parameter settings; The test parameters to be set include series excitation system parameters, self-test parameters, transfer function identification parameters, window compensation coefficient, and safety parameters; S2. System self-test: According to the self-test start voltage, send a pseudo-random signal obtained by broadband powder noise spectrum conversion and gradually increase it until it reaches the self-test level; by detecting the output of the detection system, determine whether the series excitation system is working properly. If it is normal, proceed to the next step; otherwise, end. S3. Transfer Function Identification: Based on the identification level set in the series excitation system, the pseudo-random signal obtained by broadband powder noise spectrum conversion is used to identify the transfer function of the series excitation system. During the transfer function identification process, transfer function identification is performed separately for the low-frequency station and the high-frequency station: the identification signal is sent to turn on the low-frequency station drive system and turn off the high-frequency station drive system, thereby completing the transfer function identification of the low-frequency station; conversely, the transfer function identification of the high-frequency station is completed. S4. Single-frame periodic cyclic vibration control; S41. First, obtain single-frame data from the vibration controller and perform FFT transformation; S42. Apply a low-frequency window to obtain the low-frequency drive spectrum signal and apply a high-frequency window to obtain the high-frequency drive spectrum signal. S43. The low-frequency drive spectrum signal is multiplied by the inverse transfer function of the low-frequency station, and then transformed by IFFT to obtain the time-domain drive frame signal. Finally, the effective frame drive signal is extracted and output to the low-frequency station using the frame extraction method. S44. The high-frequency drive spectrum signal is multiplied by the inverse transfer function of the high-frequency station, and then transformed by IFFT to obtain the time-domain drive frame signal. Finally, the effective frame drive signal is extracted and output to the high-frequency station using the frame extraction method. S45. This realizes the frequency division control of the series excitation system.

2. The frequency division vibration control method applicable to a series excitation system according to claim 1, characterized in that, In step S3, the system transfer function identification using the pseudo-random signal obtained by wideband powder noise spectrum conversion includes: using the powder noise pseudo-random signal, obtaining multiple transfer function samples in the frequency domain under frame data shifting, and then calculating the transfer function of the series excitation system as follows: here, Represents m samples The sample in; H m This represents the transfer function for the m-th linear average of m samples, where m is the set number of averages. Therefore, the transfer function H of the low-frequency station is calculated respectively. md The transfer function H of the high frequency station mh .

3. The frequency division vibration control method applicable to a series excitation system according to claim 2, characterized in that, When conducting a steady random vibration test, step S441 is set between steps S44 and S45. Step S441 includes: using the low-frequency and high-frequency station crossover frequency calculation method to obtain the accurate time-domain frequency division point; using the output results of the low-frequency station and the high-frequency station in series to obtain the acceleration output signal of the series excitation system; combining the single-frame drive signal of the vibration controller to calculate the transfer function of the series excitation system; obtaining the standard normalized transfer function of the series excitation system through the transfer function overlap method; comparing the current system transfer function with the standard normalized transfer function of the series excitation system; and updating the low-frequency window function and the high-frequency window function by updating the low-frequency and high-frequency window functions.

4. The frequency division vibration control method applicable to a series excitation system according to claim 1, characterized in that, In step S4, the frame extraction method includes: extracting the middle segment from a single frame as the number of valid frame points, wherein the formula for calculating the number of valid frame points is as follows: Where L represents the number of points in a single frame, and N is the number of valid frame points extracted.

5. A frequency-division vibration control method applicable to a series-type excitation system according to claim 3, characterized in that, In step S441, the method for calculating the crossover frequency of low- and high-frequency stations includes: Using the transfer function H of the obtained low-frequency station md The transfer function H of the high frequency station mh The root mean square ratio A of the input and output signals in the low-frequency station transfer function identification process is used as a reference value; whereby the root mean square ratio A is calculated as follows: The normalized value A of the amplitude-frequency response is calculated as follows: Here, Y rms X represents the root mean square value of the low-frequency station's output signal. rms This represents the root mean square value of the input signal to the low-frequency station; In addition, according to the transfer function amplitude-frequency value abs(H) of the low-frequency station md Based on the given upper limit of the low-frequency station frequency, the search amplitude value is approximately equal to... The corresponding frequency value is used as the crossover frequency between the low- and high-frequency stations.

6. The frequency division vibration control method applicable to a series excitation system according to claim 5, characterized in that, In step S441, the method for obtaining the system standard normalized transfer function includes: First, the amplitude frequency value of the system's standard normalized transfer function is set to 1. The phase frequency value of the transfer function is then overlapped based on the crossover frequency, connecting the phase frequency values ​​of the transfer functions from the low-frequency and high-frequency stations. During the overlapping process, a weighted transition overlap is performed 10*ΔfHz to the left and right of the crossover frequency. The overlapping method is as follows: Specifically, at positions 10*ΔfHz to the left and right of the crossover frequency, the phase frequency of the low-frequency station is: θ d(-10) ~θ d(0) ~θ d(10) , where θ d(0) The low-frequency phase frequency value at the crossover frequency; At positions 10*ΔfHz to the left and right of the crossover frequency, the phase frequency value of the high-frequency station is: λ g(-10) ~λ g(0) ~λ g(10) , where λ g(0) The phase frequency value of the high-frequency station at the crossover frequency; In addition, the parameters of the series excitation system include sampling frequency, number of spectral lines, number of points per frame, system frequency range, and accelerometer sensitivity. Δf represents the frequency resolution, and Δf is calculated as follows: Where L represents the number of points per frame, f s The sampling frequency; Therefore, near the crossover frequency, the phase frequency of the system's standard normalized transfer function is: Where i = -10, ..., 0, ..., 10; thus, the normalized transfer function of the system is obtained.

7. A frequency-division vibration control method applicable to a series-type excitation system according to claim 2, characterized in that, In step S441, the method for updating the high and low frequency domain window functions includes: In single-frame periodic cyclic vibration control, the system's transfer function is identified using the single-frame input and output signals through a transfer function identification method. Based on the identified system transfer function and the system's standard normalized transfer function, high- and low-frequency domain window functions are obtained; where the high- and low-frequency domain window functions Win... A The calculation is as follows: Among them, H s This indicates the identified system transmission. This indicates a system standard normalized transfer function; Then, using the crossover frequency as the frequency coordinate dividing point, the high and low frequency domain window functions are split into a low-frequency window function Win. d and high-frequency window function Win g The low-frequency window compensation coefficient λ d High frequency λ g Finally, the updated low-frequency window function is obtained. and high-frequency window functions The calculation method is as follows: Finally, the updated low-frequency window function will be... and high-frequency window functions The single-frame FFT spectrum of the controller drive signal is windowed, and this process is repeated cyclically to complete the frequency division control of the system.

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