156 results about "Damping ratio" patented technology

The invention discloses a harbor shore power system oscillation damping suppression method based on heuristic probability optimization. According to the method, sliding window preprocessing is carried out on an alternating current bus side current time domain oscillation signal, modal decomposition is carried out based on a Prony algorithm, and modal energy is calculated to judge an oscillation mode; the discriminated oscillation modes are aggregated and mapped into equivalent circuit elements, a corresponding three-order circuit state matrix is constructed, and the damping ratio of each mode is determined according to the characteristic value of the matrix; taking a damping ratio as an evaluation index, introducing an influence factor to construct a multi-objective optimization function, parameterizing the parallel adjustable impedance, and limiting an adjustable range; and searching the control parameters by adopting a heuristic probability optimization strategy to obtain final damping control parameters, and downloading the final damping control parameters to the parallel adjustable impedance device to realize online dynamic adjustment. According to the method, multi-modal identification, physical magnitude mapping and online adaptive optimization can be realized, and the suppression capability and the operation stability of the shore power system on sub / super synchronous oscillation are improved.

The invention relates to a large-span bridge flutter critical wind speed prediction method based on an L-P perturbation method. The method comprises the following steps that S1, physical characteristics and aerodynamic parameters of a bridge are obtained through a wind tunnel test to serve as basic data; s2, establishing a bridge motion control matrix equation based on modal displacement; s3, deriving an explicit solution of the modal frequency, the damping ratio and the modal characteristic of each modal branch based on an L-P perturbation method; s4, iteratively solving the modal frequency, directly solving the damping ratio, the amplitude ratio and the phase difference on the basis, observing the change of the modal damping ratio xi in each direction along with the wind speed U, and determining the flutter critical wind speed; the problems that an explicit closed solution of an existing three-degree-of-freedom flutter starting condition needs to carry out multiple times of iterative calculation on modal frequency, damping ratio and vibration mode, the influence of structural parameters and pneumatic parameters on pneumatic instability is difficult to clearly explain, and the flutter critical wind speed of a large-span bridge cannot be well predicted are solved.

The invention discloses a wind turbine generator blade damage judgment method and detection system based on voiceprint detection, and belongs to the technical field of wind turbine generator blade detection. The damage judgment method comprises the following steps: acquiring environmental parameters of a wind power plant, and establishing a sound velocity correction model based on the environmental parameters; acquiring a blade resonance sound signal, and correcting the blade resonance sound signal based on the sound velocity correction model to obtain a blade resonance sound signal with a high signal-to-noise ratio; performing FFT spectrum analysis on the blade resonance sound signal with the high signal-to-noise ratio, identifying the peak position of the first three-order natural resonance frequency of the blade, and performing analysis to obtain the current modal frequency, damping ratio and sub-band energy distribution entropy value of the blade; historical baselines of the modal frequency, the damping ratio and the sub-band energy distribution entropy of the blade in the healthy state are obtained, and the modal frequency offset, the damping ratio change rate and the acoustic impedance spectrum entropy of the blade are obtained; and wind turbine generator blade damage determination is carried out by using a high-precision time difference detection technology.

The invention belongs to the field of structural modal identification, and particularly relates to an automatic modal parameter identification method based on a multi-scale space, which comprises the following steps: collecting a vibration data sample from a target structure, the vibration data sample comprising an acceleration signal of the structure; selecting power spectrum calculation parameters including a window function and a fast Fourier transform (FFT) length; performing frequency spectrum estimation on the acceleration signal by using interpolation power spectrum estimation to obtain frequency spectrum data; analyzing the spectrum data by using a multi-scale space algorithm, and detecting a peak value in the spectrum data to obtain a peak value frequency; through a frequency domain decomposition method, according to the peak frequency, modal parameters of the structure are calculated, the modal parameters comprise the modal frequency and the damping ratio, interpolation power spectrum estimation and a multi-scale space algorithm are innovatively combined, automatic and accurate identification of the modal parameters is achieved, and the identification precision and efficiency are remarkably improved.

The invention discloses an ultrasonic welding quality online detection system and method, and belongs to the technical field of laser non-contact measurement. According to the invention, the laser vibration measurement probe is rigidly coupled to the welding head to construct a follow-up-common-optical-path measurement unit, so that synchronous acquisition of vibration signals with zero mass loading is realized; further extracting an attenuation section after welding is finished from the signal, and inverting an equivalent modal damping ratio representing an interface energy dissipation state based on an exponential attenuation model; meanwhile, multi-dimensional physical indexes such as an energy transfer efficiency index Itrans and an input stability index Iin are calculated, and in combination with an energy absorption state index, collaborative fusion is carried out through a weighted fusion formula to obtain a comprehensive quality score; and finally, realizing quality attenuation early warning based on time sequence trend analysis of a scoring sequence. On-line sensing of the deep dynamic state in the welding process is achieved, the early defect recognition sensitivity and the system anti-interference capacity are remarkably improved, and the predictive maintenance capacity of quality degradation is achieved.

The invention belongs to the technical field of low-frequency vibration control, and discloses a low-frequency low-damping tuned mass damping device which is mainly composed of a rigid support, a first sling, a rotating arm, a cable hole, a first arc guide groove, a second arc guide groove, a lock pin, a second sling, a first mass block, a spring, a second mass block and a damping element. The flexible suspension rotation replaces the bearing or ball screw support, so that the damping is obviously reduced; the long rotating arm is combined with the equivalent large-diameter arc guide groove, so that the low-frequency low-damping tuned mass damping device can achieve large vertical displacement at a small rotating angle, and damping is reduced. The low-frequency low-damping tuned mass damping device innovatively adopts double-mass-block configuration, so that static force borne by a spring is generated by mass difference, and static deformation of the spring is remarkably shortened. According to the method, low-frequency operation can be achieved under the condition that the space is limited, the low-damping characteristic is kept, it is guaranteed that the requirement for the optimal damping ratio is met, and therefore a new technical approach is provided for control over low-frequency vortex vibration of a large-span bridge.

The invention provides a bridge vortex-induced vibration and flutter control TMDI parameter optimization method, which comprises the following steps of: according to a selected inertia mass ratio, obtaining optimal values of parameters under a control target by adopting a GBO optimization algorithm, wherein the optimal values are a TMDI mass ratio, a frequency ratio and a damping ratio; according to the optimization algorithm, the target function Fs converges to the minimum individual, namely the minimum TMDI mass ratio, and the minimum TMDI mass ratio and the corresponding optimal parameter, namely the optimal combination parameter. The invention further provides equipment, a storage medium and a program product. Compared with the prior art, the method has the advantages that the most economical TMDI optimization parameters can be obtained while effectiveness and robustness are considered.

The invention discloses a PLC-based high-pressure-ratio magnetic suspension centrifugal heat pump control method and system, and the method comprises the steps: carrying out the self-adaptive sampling rate adjustment through collecting operation data and PLC configuration information, generating a dynamic signal matrix, recognizing a key pressure ratio control loop, and extracting vibration envelope and surge precursor frequency to generate early warning characteristic parameters; reversely adjusting the rigidity damping ratio of the magnetic bearing to determine an anti-surge protection boundary; fin temperature difference detection information is monitored, a partition defrosting map is generated through asymmetric frosting rate analysis, and minimum energy consumption analysis is executed to determine a reversing valve switching time sequence; performing operation characteristic and oil-gas migration coupling analysis to generate oil-gas separation optimization parameters, adjusting a magnetic suspension gap to extract a zero-power-consumption suspension interval, and constructing layered energy-saving control configuration; a preventive maintenance time window is generated through magnetic bearing current ripples, a fault-tolerant degradation operation mode and a self-adaptive control strategy are established, a heat pump control instruction is finally generated, and intelligent control over the high-pressure-ratio magnetic suspension centrifugal heat pump is achieved.

The invention provides a blade fault diagnosis method and device based on vibration of a wind generating set, and relates to the technical field of blade fault diagnosis of vibration of the wind generating set. The first-order modal frequency and damping ratio of the blade under different working conditions are accurately recognized through phase compensation and frequency response function calculation, modal parameters of a plurality of working condition points are connected in sequence to construct a dynamic response track, and a local mode feature vector is formed by calculating relative vectors of each point and other points in the track. And further integrating into a global mode feature matrix, obtaining a trajectory mode deviation index by calculating the Frobenius norm of the to-be-monitored matrix and the reference matrix, and judging the structural damage according to the statistical law that the index continuously exceeds the threshold.

The present application provides a kind of transmission conductor negative stiffness damper, provides damping by another connection damper, negative stiffness device increases damping ratio, realizes conductor model damping effect;Main components are arranged side by side by fixed magnet and movable magnet, the interaction force between its magnets is basically linear increase, that is, it can guarantee constant negative stiffness value, damping effect is obvious and model loss is small, and durability is strong;Light weight, convenient transportation, easy to install and maintain;Transmission conductor negative stiffness damper is rigidly connected with insulator string as a whole, and can effectively transmit the vibration of conductor galloping;The present application is novel and unique in design, has wide range of application, and has good popularization and application value and economic benefits.

The application discloses an inverter power three-phase short-circuit fault current analytic method considering a phase-locked loop and a current inner loop transient process, and belongs to the technical field of photovoltaic grid-connected system fault analysis. The application studies the transient process of SRF-PLL under different damping ratios, analyzes the influence of the transient process of SRF-PLL on the coordinate transformation of PCC point voltage and current, finally considers the influence of the transient process of SRF-PLL and the current inner loop on the fault current, introduces a correction coefficient, and decomposes the phase current component expressions of the inverter port fault current into the phase current components of the inverter port current under the first influence condition and the phase current components of the inverter port current under the second influence condition. Through the application, the transient characteristics of the IIDG can be more accurately analyzed, the short-circuit characteristic analysis of the IIDG is perfected, and a reference basis is provided for the fault characteristic analysis of the IIDG.

This invention discloses a method for correcting the phase difference between aerodynamic and displacement signals in wind tunnel tests based on self-excited vibration characteristics. The method includes: independently acquiring wind pressure and vibration displacement signals from the structural surface; integrating the wind pressure signal to obtain the self-excited aerodynamic time history; identifying the vibration frequency and the total system damping ratio from the displacement signal; filtering the aerodynamic time history to extract the fundamental frequency component; establishing an analytical relationship between the aerodynamic out-of-phase component coefficient and the total system damping based on the structural dynamic equilibrium principle; and iteratively shifting the aerodynamic time history using the displacement signal as a reference until the out-of-phase components satisfy the analytical relationship, thereby determining and correcting the system delay. This invention also discloses a system and storage medium for correcting the phase difference between aerodynamic and displacement signals in wind tunnel tests based on self-excited vibration characteristics. This invention requires no additional hardware and can accurately compensate for electrical triggering and physical transmission delays, effectively improving the reliability of aerodynamic parameter identification.

The application discloses a new energy base phase modifier synchronous instability analysis method and system, and belongs to the technical field of power system stability analysis. The method comprises the following steps: obtaining a training data set covering multi-dimensional power grid parameters and fault scenes, calculating dominant degree factors based on the coupling dynamic index of inverters, and dividing multiple dominant degree factor intervals to represent the control dominance of different types of inverters; a risk guardrail set containing a power coupling index and a damping ratio change amount is constructed, and a differentiated threshold is set for each interval; the control parameters of the inverters are extracted and a candidate boundary line set is generated, the performance of the candidate boundary line set is evaluated through transient simulation, the priority value is calculated by comprehensively considering the deployable proportion, the time benchmark ratio and the safety coefficient, and the optimal target boundary line is selected; finally, the target boundary line parameters are mapped into adaptive control gears, and the coordinated control of the phase modifier and the inverter is realized in combination with the real-time risk state, so that the synchronous instability risk is effectively inhibited.

The invention discloses a bridge frequency and damping identification method based on single position acceleration quadratic integral, and relates to the technical field of bridge monitoring, and the method comprises the steps: reconstructing a displacement signal of a bridge through quadratic integral operation for an original acceleration signal of a single acceleration sensor; performing modeling analysis on the original acceleration signal by using a physical information neural network model, and subtracting the displacement signal to obtain a vibration signal; and analyzing the vibration signal by using a fourth-order autoregression model, extracting and selecting conjugate complex poles which conform to the main vibration mode characteristics of the bridge, and obtaining the inherent frequency and damping ratio of the bridge. Only a single acceleration sensor is needed, and the system cost is greatly reduced. Secondly, the signal quality is greatly improved through the physical information neural network model, the inherent frequency and the damping ratio of the inherent frequency can be accurately extracted even if the four-order autoregression model is applied to a single-point response signal, and the method has the advantages of being high in noise robustness, accurate in calculation and the like.

The present application belongs to the technical field of low-frequency vibration control, aiming at the problems of high damping ratio, instability, low vibration control efficiency and unsuitable for large-scale engineering of existing inertial damper, a low-damping tuned inertial damper device is provided, which provides the possibility for the whole system to realize the required optimal damping ratio, and further efficiently controls low-frequency resonance. Unlike traditional rigid support and transmission mode, the device adopts economical, reliable and convenient flexible suspension support and transmission mode to realize low frequency and stable low damping of the system. The flexible support part and the rigid inertial device are in contact transmission around, which eliminates the high damping caused by high energy consumption due to instability caused by friction and collision in traditional inertial tuned mass damper, so as to ensure that the large inertial system realizes stable low damping ratio, meets the needs of realizing optimal control effect, and is directly applied to large engineering structure resonance control.

The invention belongs to the field of spacecraft modal testing, and particularly relates to a modal testing method based on dynamic modal decomposition in an unfolded state of a large flexible solar wing, which comprises the following steps of: S1, exciting the solar wing by adopting a pre-tightening force release method, and synchronously acquiring displacement attenuation data of different positions of the solar wing through a plurality of laser displacement sensors in a testing device; s2, performing fast Fourier transform calculation on each group of displacement attenuation data, and processing all fast Fourier transform calculation results to generate an average frequency response curve; s3, processing the displacement data by adopting a Monte Carlo delay embedding dynamic mode decomposition algorithm to obtain Q groups of fundamental frequencies, damping ratios and vibration mode results; and S4, arithmetic average is carried out on Q groups of results, and a final fundamental frequency, a modal damping ratio and a vibration mode are output. According to the method, the modal parameters are identified by adopting the Monte Carlo dynamic modal decomposition method, the fundamental frequency, the modal damping ratio and the vibration mode of the unfolded state of the large flexible solar wing can be identified, and meanwhile, the reliability of an identification result is ensured.

The present application relates to building energy dissipation and shock absorption technical field, disclose a kind of based on optimal additional damping ratio viscous damper parameter design method, including the following steps: the first-order natural frequency of non-damping structure is calculated;The vertex displacement amplitude of structure under the action of frequently occurring earthquake is calculated;The inter-story displacement amplitude of the i floor of structure arranged with damper and the corresponding inter-story displacement amplitude average are calculated;The first-order equivalent modal stiffness of viscous damper connecting component is calculated;The traversal numerical solution of damper damping index is calculated;The value of damping coefficient when additional damping ratio obtains maximum is calculated and so on step.The present application can calculate the specific value of viscous damper damping coefficient and damping index when additional damping ratio obtains maximum according to the basic parameter of structure, and the corresponding maximum value of additional damping ratio is calculated, and it has important significance to damage control and optimization design of damper parameter of viscous damper shock absorption structure under the action of earthquake.

The invention discloses a multiple-input-multiple-output bridge modal parameter identification method and device based on a corrected periodogram method power spectrum, and the method comprises the steps: obtaining a section of multi-point input excitation and multi-point output response, and equally dividing the excitation and response data according to the dimension of an excitation vector; the equant excitation and response data are substituted into a response power spectrum matrix calculation formula for separating excitation, singular value decomposition is carried out on the obtained matrix to obtain a maximum singular value curve and a singular vector, the frequency corresponding to the peak value of the curve is the inherent frequency of the bridge, the corresponding singular vector is the vibration mode of the bridge, and the maximum singular value curve is obtained. The frequency corresponding to the half of the peak value of the curve is a half-power point, and the half-power point is substituted into a damping ratio calculation formula to obtain the damping ratio of the bridge. And substituting the damping ratio, the vibration mode and the inherent frequency into a vibration mode scaling coefficient calculation formula to obtain the vibration mode scaling coefficient of the bridge. In the bridge operation modal parameter identification process, the problem that an excited autopower spectrum ill-conditioned condition is difficult to invert is solved, and the identification precision of the bridge modal parameters is improved.

The invention discloses a power system oscillation parameter identification method based on improved TVF-EMD, and the method comprises the steps: carrying out the preprocessing of an original PMU data stream, calculating a local cut-off frequency LCF through B-spline approximation, solving a signal local mean value through B-spline approximation, completing the time-varying filtering empirical mode decomposition, namely TVF-EMD decomposition, screening an effective IMF based on a correlation coefficient after the verification of a stop criterion, and carrying out the recognition of the oscillation parameter of a power system. Extracting an instantaneous frequency and a damping ratio through the TKEO; the method combines TVF-EMD with TKEO, can accurately estimate the modal parameters of the power system under the normal operation condition, including frequency and damping ratio, has robustness for the instantaneous mode characteristics in the power system under the condition of low calculation complexity, reduces the problems of modal aliasing and discontinuity easily occurring in the traditional EMD method, and improves the reliability of the power system. The method provides better performance in the aspects of predefined parameters and time-varying cut-off frequency, and is suitable for analysis of non-stationary signals.

The invention relates to the technical field of earthquake resistance of bridge engineering, and particularly discloses a railway beam bridge damping system based on metal damper coordination and a design method.The railway beam bridge damping system adopts direct displacement design based on equivalent linearization and comprises the steps that firstly, shock insulation displacement and an initial equivalent damping ratio are set as design parameters; the design displacement target is achieved within the reasonable range of the two parameters, accurate calculation can be conducted according to specific structural requirements, blind accumulation only based on the number of existing dampers in previous design is avoided, and design pertinence and scientificity are effectively improved. On the premise that different metal dampers are combined, the independent design of the equivalent damping ratio and the equivalent rigidity is achieved, the flexibility of the damping design is improved, the damping design of a common railway beam bridge is optimized, and the cost of the damping device is reduced.

The invention provides a power distribution network harmonic instability critical damping dynamic early warning method and system. The method comprises the steps that harmonic voltage and harmonic current of key nodes of a target power distribution network are acquired every first preset time; identifying the harmonic voltage and the harmonic current according to a first preset rule so as to obtain equivalent harmonic impedance under a preset harmonic frequency according to an identification result; calculating a system damping ratio corresponding to a preset harmonic frequency according to the equivalent harmonic impedance; judging whether the system damping ratio is smaller than or equal to a preset damping ratio threshold value; and if the system damping ratio is smaller than or equal to the preset damping ratio threshold value, generating a harmonic instability early warning signal. According to the invention, the accuracy and practicability of early warning can be effectively improved.

The application relates to an electromagnetic damping vibration damper, which comprises a wire clamp, a sleeve, permanent magnet hammers and springs. One end of the sleeve is fixedly connected with the wire clamp, the inside of the sleeve is provided with a buffer cavity, and the inner wall of the buffer cavity is entirely covered with an eddy current copper plate. The permanent magnet hammers are arranged in the buffer cavity along the axial direction of the sleeve, the permanent magnet hammers can slide along the axial direction of the sleeve, and a working gap is arranged between the permanent magnet hammers and the eddy current copper plate. One end of the spring is fixedly connected with the permanent magnet hammer, and the other end is fixedly connected with the permanent magnet hammer or the end of the buffer cavity. Four permanent magnet hammers and two adjacent springs are matched to form four groups of electromagnetic energy dissipation units, the natural frequencies of the four groups of electromagnetic energy dissipation units are F1, F2, F3 and F4, and the damping ratio of the four groups of electromagnetic energy dissipation units is between 0 and 1. Each group of electromagnetic energy dissipation units corresponds to an independent natural frequency, four discrete resonance frequency points are formed, and the core frequency band 0-150Hz of the overhead transmission line wind vibration is covered.

The present application relates to rock mass identification and early warning technical field, especially point to a kind of based on double index's toppling type dangerous rock mass identification method and device.Method includes: obtaining the rock bridge length of the toppling type dangerous rock mass to be identified, rock bridge stiffness coefficient, rock mass quality, friction coefficient on structural plane and effective normal stress;Based on calculating damping ratio and inherent vibration frequency;Based on inherent vibration frequency, damping ratio and rock mass quality, calculate rock bridge strength;Based on rock bridge strength, inherent vibration frequency and damping ratio, calculate the dynamic safety factor;Based on inherent vibration frequency and damping ratio, calculate weak stable dynamic safety factor;Based on dynamic safety factor and weak stable dynamic safety factor, according to preset identification rule, toppling type dangerous rock mass is identified, and identification result is obtained.The present application realizes the rapid damage identification of toppling type dangerous rock mass.

The application discloses a passive-based phase-locked loop parameter adaptive optimization method under a weak power grid, which comprises the following steps: (I) a dynamic coupling model of a phase-locked loop and a converter system under a weak power grid is established, and the influence mechanism of the phase-locked loop parameters on the stability of the system is analyzed; (II) a real-time calculation method of an equivalent short-circuit ratio of the system is derived based on the passive theory, and a short-circuit ratio-parameter sensitivity relationship matrix is constructed; (III) the short-circuit ratio of the power grid is dynamically perceived, the bandwidth coefficient and the damping ratio parameters of the phase-locked loop are adaptively adjusted, and the harmonic oscillation or instability risk caused by the fixed parameters is eliminated. The application ensures the stable operation of the system under all working conditions, and can significantly improve the dynamic stability and robustness of the wind turbine under the working condition of the low short-circuit ratio weak power grid.

The invention relates to the technical field of unmanned aerial vehicle calibration, in particular to an unmanned aerial vehicle holder calibration method and device and electronic equipment, and the method comprises the steps: controlling a frame shaft of a holder to enter a free state; initial angular displacement is applied to the frame shaft in the free state, so that the frame shaft is subjected to free damped oscillation; acquiring a time-varying attenuation response data sequence of the angular displacement of the frame shaft in free attenuation oscillation; fitting the attenuation response data sequence with a preset system model, wherein the system model comprises kinetic parameters used for representing the rotational inertia and the damping ratio of the frame shaft, and constant offset parameters used for representing the zero deviation of the angle sensor; and according to a fitting result, calculating a numerical value of the constant offset parameter as a zero calibration value, and driving a motor of the holder according to the zero calibration value, so that the frame shaft rotates and is locked in a calibrated zero posture. According to the method, the calibration process is simplified, and errors caused by manual observation or dependence on unstable reference are avoided.

A kind of operating condition under rotating electric machine inherent frequency calculation method discloses a kind of operating condition under rotating electric machine inherent frequency acquisition method, belong to motor structure modal parameter online identification technical field.Method includes: in stator tooth portion uniform distribution N≥4 one-way vibration sensor;Motor is under load and vibration signal is synchronously collected;Signal zero-phase band-pass filtering;The correlation function of reference point and response point is calculated, and complex modal modeling is complex exponential series;Through single-sided mutual power spectrum transformation and multiple starting time sampling matrix equation is constructed, coefficient vector is obtained by SVD solution;Root is sought by coefficient and constructs characteristic polynomial, mapping obtains system continuous pole, and then simultaneously output inherent frequency and damping ratio.The whole process does not need to stop, does not need to add excitation, noise resistance is strong, frequency identification error is less than 1%, provides modal data under real boundary condition for motor NVH optimization and structural modification.

The invention discloses a bridge damping ratio rapid identification method based on a static detection vehicle, and relates to the technical field of bridge structure vibration tests.The method comprises the steps that the detection vehicle statically stops at the midspan position of a bridge to be detected, the bridge is driven away after being excited by a passing vehicle to vibrate, and the acceleration response of the detection vehicle in an attenuation section is collected; establishing an attenuation section dynamic model of the detection vehicle-bridge coupling system; constructing a two-degree-of-freedom joint state model, and internalizing an axle interaction force into a linear combination of system state variables; an effective attenuation section is extracted through signal preprocessing, and a dual anti-noise mechanism of a signal-to-noise ratio adaptive weight and a Huber weight is introduced; a section two-stage parameter identification strategy is adopted, the frequency and modal quality are locked firstly, and then the first-order damping ratio of the bridge is identified through fine scanning. The method only needs a single detection vehicle and an acceleration sensor, does not need to arrange a sensor on a bridge body, is high in anti-interference performance, is high in recognition precision, and is suitable for the rapid inspection of small and medium span bridges.

The invention discloses a pool vibration isolation and noise reduction design system based on dynamic characteristic analysis. The system comprises a sensor array, a data acquisition and preprocessing module, a dynamic characteristic analysis module, an active actuator array, an underwater acoustic control module and a central controller. Vibration and noise signals of a pool structure are collected in real time through a sensor, and dynamic characteristic parameters such as the inherent frequency and the damping ratio of the structure are analyzed online through algorithms such as random subspace recognition; based on the parameters, the central controller respectively drives the actuator array and the underwater secondary sound source by adopting a self-adaptive control algorithm and an acoustic active control algorithm to generate a reverse acting force and an anti-noise signal so as to cooperatively suppress structural vibration and underwater noise; according to the invention, the defect that the traditional static design is difficult to adapt to the dynamic change of the fluid-structure interaction system is overcome, intelligent and self-adaptive integrated cooperative control of vibration reduction and noise reduction is realized, and the control precision, stability and efficiency are remarkably improved.

The application discloses a kind of video vibration two-dimensional modal identification method and equipment based on depth completion pyramid, belong to structural vibration measurement and modal identification technical field;First, the depth image sequence in the two-dimensional vibration process of measured structure is obtained;The sparse depth image of depth image sequence is directionally depth completed to construct Gaussian pyramid, and depth completion pyramid is constructed in combination with the Gaussian pyramid of adjacent scale, and the target layer is selected for fusion reconstruction;Then, the reconstructed depth sequence is sequentially subjected to difference amplification, transposition compression and direct current removal processing to construct a unified input matrix;Then, the input matrix is subjected to PDD method and H-DMD method to extract natural frequency, damping ratio and modal shape from two dimensions of frequency domain and time domain;Finally, the decomposition results of PDD method and H-DMD method are jointly checked, and the modal identification result of the structure is output.The two-dimensional structural vibration modal result obtained by the method is improved in terms of parameter integrity, spatial continuity and physical consistency.

The utility model discloses a semi-active tuned mass damping system based on an adjustable damping structure. The semi-active tuned mass damping system comprises a mass unit, an adjustable spring unit, a damping unit, a guide unit and a mounting bottom plate, the mass unit comprises a fixed mass assembly and a free mass assembly; the fixed mass assembly comprises a top plate, a middle plate and a guide unit mounting plate; the free mass assembly comprises two free mass blocks arranged between the top plate and the middle plate; each free mass block comprises a plurality of detachable steel plates which are stacked from bottom to top; the adjustable spring unit comprises a plurality of springs; the guide unit comprises a guide rod and a sliding piece; the damping unit comprises a viscous damper, a hydraulic loop arranged between two hydraulic cavities of the viscous damper and a valve block. An adjustable damping structure and a hydraulic valve are arranged in the valve block; by measuring the frequency of the main structure and the TMD and adjusting the displacement and the rotating angle of the valve element of the adjustable damping structure, semi-active adjustment of the damping ratio is achieved, and then the frequency change of the main structure is adapted.