71 results about "Resonance analysis" patented technology

The invention relates to the technical field of route planning, in particular to an underground cavern inspection method and system. The method comprises the following steps: acquiring geological survey data, micro-seismic monitoring data and historical deformation monitoring data; according to the geological survey data and the micro-seismic monitoring data, rock mass viscoelasticity local modeling is carried out, and a rock mass viscoelasticity model is obtained; performing deformation trend prediction according to the rock mass viscoelastic model and the historical deformation monitoring data to obtain deformation trend data; performing deformation disturbance resonance analysis according to the deformation trend data and the micro-seismic monitoring data to obtain deformation disturbance resonance data; performing risk area grading on the deformation disturbance resonance data to obtain risk area grading data; and generating a routing inspection graph according to the risk area grading data to obtain routing inspection graph data so as to carry out underground cavern routing inspection auxiliary operation. The method accurately identifies the potential risk area, dynamically plans the inspection task, and improves the inspection efficiency and decision timeliness.

The invention discloses a computing platform management system based on artificial intelligence, particularly relates to the technical field of distributed storage resource dynamic allocation, and is used for solving the problem of resource allocation oscillation caused by hardware performance difference and dynamic attenuation in the prior art. Acquiring the hardware performance, the load state and the data path of the storage node through a real-time acquisition module; the entropy judgment module calculates a path topology entropy and triggers a reconstruction instruction; the resonance analysis module analyzes the group association strength of hardware performance degradation and marks a resonance node group; the weight generation module fuses the parameters to generate a dynamic allocation weight; the error compensation module optimizes a weight coefficient in combination with historical error data; the migration execution module executes migration according to the weight and limits the load of the resonance node; through cooperative regulation and control of topological entropy monitoring and hardware resonance analysis, local oscillation diffusion is inhibited, unnecessary migration operation is reduced, system stability is improved, and the service life of hardware is prolonged.

The invention discloses a server energy-saving system and method based on a lag compensation type dynamic thermal impedance model, and relates to the field of server energy saving.By collecting operation data of a server hardware bottom layer in real time, a multi-dimensional thermal-computing force coupling time sequence atlas is constructed, and based on the multi-dimensional thermal-computing force coupling time sequence atlas, a dynamic thermal impedance model is established. Calculating a heat conduction time constant of hardware in a current environment; establishing a lag compensation type dynamic thermal impedance model based on the heat conduction time constant; constructing a thermodynamic phase space according to operation data; analyzing a noise reduction evolution trajectory in combination with the lag compensation type dynamic thermal impedance model; the method comprises the steps of generating a weighted thermal resonance state vector, activating an adaptive gain MPC predictive damping scheduling strategy based on the weighted thermal resonance state vector, constructing and solving a dynamic weighted multi-objective optimization function, generating an optimal damping scheduling instruction, and thoroughly solving the fan asthma phenomenon that the fan PWM duty ratio fluctuates substantially in a sine mode under the constant computing power load.

The invention discloses an intelligent evaluation system and intervention method for mental health of teenagers, and the method comprises the following steps: collecting multi-mode psychological signal data of the teenagers, and carrying out the preprocessing; establishing a cognitive energy field, and generating a cognitive energy time sequence curve; performing spectrum resonance analysis, and combining the spectrum resonance analysis with a cognitive energy time sequence curve; constructing a psychological topological graph, and calculating a topological complexity index; when the topology complexity index is continuously abnormal or the cognitive energy disturbance amplitude exceeds a set threshold value, a psychological risk early warning result is generated; after the psychological unstable state is detected, a cognitive energy feedback parameter set is generated, and cognitive energy balance intervention is executed; and after the intervention is finished, calculating an energy balance improvement rate, and when the energy balance improvement rate exceeds an energy balance threshold, judging that the intervention is finished. According to the method, multi-mode psychological signals and cognitive energy field modeling are fused, intelligent evaluation and dynamic intervention of the psychological state of the teenagers are achieved, and the method has the advantages of being high in accuracy, high in interpretability and closed in intervention loop.

The invention relates to the technical field of data processing, and discloses a high-voltage frequency conversion and speed regulation all-in-one machine fault diagnosis method and system, and the method comprises the steps: injecting a voltage signal with a preset characteristic frequency into a frequency converter control loop, and obtaining a mixed voltage signal of the frequency converter control loop; separating a common-mode current characteristic waveform of a current signal in the mixed voltage signal in an excitation state; performing high-frequency resonance analysis on the vibration signal of the end part of the stator winding to obtain an insulation defect characteristic frequency spectrum of the end part of the stator winding; performing time-frequency domain correlation analysis on the common-mode current characteristic waveform and the insulation defect characteristic frequency spectrum to obtain an insulation defect characteristic matrix of the high-voltage frequency conversion and speed regulation all-in-one machine; performing degradation degree evaluation on amplitude change and distribution modes of characteristic frequency components in the insulation defect characteristic matrix to obtain a winding insulation degradation level of the high-voltage frequency conversion and speed regulation all-in-one machine; according to the invention, the fault diagnosis accuracy of the high-voltage frequency conversion and speed regulation all-in-one machine can be improved.

The invention relates to an establishment method and application of a ground resonance nonlinear analysis model, and belongs to the technical field of analysis model establishment methods and application. In order to overcome the defect that an accurate ground resonance analysis conclusion cannot be obtained due to the fact that nonlinear mechanical characteristics of a rotor wing shimmy damper and a machine body damper are not considered in the prior art, the invention provides an establishment method of a ground resonance nonlinear analysis model. According to the method, the influence of the nonlinear factor of the blade shimmy damper and the nonlinear non-proportional damping of the body damper can be considered, and an accurate resonance analysis result is obtained. The method comprises the following steps: S1, selecting a blade shimmy damper model, calculating the acting force of a blade shimmy damper, and determining a blade shimmy motion equation; s2, calculating equivalent parameters of an aircraft body equivalent to a propeller hub center on the skid-type undercarriage under different responses, inputting longitudinal and transverse displacements and speeds of the propeller hub center, and determining an aircraft body motion equation; and S3, determining a ground resonance nonlinear analysis model.

The invention relates to the technical field of resonance analysis, in particular to an effectiveness analysis method and device for a resonance suppression strategy of a series branch of a power system. According to the method, by constructing the resonance suppression evaluation indexes and constructing the corresponding series branch resonance suppression feasible regions, effectiveness evaluation of series branch resonance suppression is achieved, and the problems that an application scene of an existing resonance suppression method is limited, and a series branch resonance scene is not matched with the resonance suppression method can be solved.

The invention discloses a multi-frequency omnidirectional unmanned aerial vehicle active defense system and method, and the method comprises the steps: obtaining defense region parameters, and constructing a navigation signal generation task library based on the coverage requirements of GPSL1 and Beidou B1 / B2 / B3 frequency bands; resonance interference points are determined through carrier locking resonance analysis, Doppler frequency shift traps are designed, frequency shift fragility features are extracted in combination with C / A code recombination processing, and a targeted interference enhancement domain is constructed; the method comprises the following steps: respectively carrying out constellation topology reconstruction on a GPS (Global Positioning System) and a Beidou system, generating false orbit parameters through ephemeris data tampering, and forming a mixed defense signal domain by utilizing carrier phase interleaving processing; analyzing signal power to determine strong and weak interference areas, and setting graded attenuation parameters to construct a graded signal attenuation field; the attenuation field and the interference enhancement domain are fused to generate dynamic simulation parameters, false orbit parameters are adjusted in real time to generate a coordinate input mode, a high-dynamic navigation signal is reconstructed, a satellite working mode is selected, an L1 / B1 / B2 / B3 multi-band radio frequency output instruction is finally generated, and all-dimensional intelligent deception jamming of the unmanned aerial vehicle navigation system is achieved.

The invention relates to the technical field of turbine blade life analysis, and discloses a single crystal turbine blade simulation piece test parameter design method and system.The critical distance is adopted to correct the dangerous position of a single crystal turbine blade high-low cycle composite fatigue simulation piece, and then resonance analysis of different orders is carried out to obtain the maximum value of the vibration stress of the dangerous position; and finally, analyzing the static stress value of the dangerous position and the maximum value of the vibration stress to obtain a high-low cycle load ratio of the dangerous film hole so as to carry out high-low cycle composite fatigue test load spectrum design of the dangerous film hole and obtain a composite fatigue test load spectrum for carrying out high-low cycle composite fatigue life test analysis on the single crystal turbine blade simulation part. The influence of the static stress gradient on the high-low cycle composite fatigue life is considered, the sensitivity of the stress gradient to the life is reduced, and the problem that the life evaluation error is large due to the fact that the evaluation is conservative by directly adopting a multi-axis fatigue model based on the stress of the stress concentration position is avoided.

The invention relates to the technical field of resonance analysis, in particular to an effectiveness evaluation method and device for a parallel resonance suppression scheme of a power system. According to the method, the parallel resonance local suppression evaluation index and the parallel resonance remote suppression evaluation index are constructed, and the corresponding feasible region is constructed, so that the parallel resonance suppression effect of the access node of the resonance suppression method and the parallel resonance action effect of other surrounding nodes are evaluated. The problems that an application scene of an existing resonance suppression method is limited, and a parallel resonance scene is not matched with the resonance suppression method are solved.

The invention provides a resonance control method and device for an offshore wind power diode rectification sending-out system. The resonance control method comprises the steps that a wind turbine generator disturbance impedance model and a twelve-pulse-wave uncontrolled rectifier disturbance impedance model are constructed; based on the disturbance impedance model of the wind turbine generator and the disturbance impedance model of the twelve-pulse-wave uncontrolled rectifier, performing interactive resonance analysis on the wind turbine generator and the twelve-pulse-wave uncontrolled rectifier to obtain an interactive stability analysis result; and on the basis of the interaction stability analysis result, control parameters of the offshore wind power diode rectification sending-out system are adjusted. The method solves the problem that in the prior art, the stability of an offshore wind power diode rectification sending-out system is not analyzed, and consequently the stability of a wind power system is poor in a complex offshore environment. According to the method, the key control parameters influencing the target node loop resistance are subjected to optimization control through the disturbance impedance model, so that the risk of interactive oscillation between the wind turbine generators is eliminated, and the operation stability of the offshore wind power diode rectification sending-out system is improved.

The invention discloses an engineering supervision project assessment management method and system based on the Internet of Things, and relates to the technical field of engineering project assessment, and the method comprises the steps: collecting and processing the field environment data and equipment data of an engineering project, and constructing an engineering field digital twinborn model; carrying out engineering equipment risk resonance analysis according to the digital twin model to construct a risk resonance matrix, and carrying out simulation risk early warning according to the risk resonance matrix; and recording the engineering field digital twin model in the block chain, updating through real-time field environment data and equipment data, and synchronously recording and storing the data by the block chain. According to the method, the accuracy of the digital twinborn model is improved, the risk resonance matrix is constructed according to the digital twinborn model and the equipment data for simulation risk analysis, the efficiency and accuracy of risk analysis are improved, and monitoring of engineering projects is effectively facilitated.

The invention provides a road dangerous chemical transportation system risk coupling assessment method based on FRAM-ISM-NK, and belongs to the technical field of road transportation safety. Comprising the following steps: identifying functional composition of a dangerous chemical transportation system based on a functional resonance analysis method (FRAM), determining risk functional elements of three core stages of transportation preparation, accident occurrence and emergency rescue, and analyzing variability; constructing a hierarchical structure relationship of risk function elements of each stage based on an interpretation structure model (ISM), and determining an action hierarchical relationship and weight between the elements; quantifying a coupling relationship between risk function elements in different stages by combining an NK model, and revealing a risk coupling mechanism; and based on the analysis result, establishing a risk transfer quantitative model, and identifying key risk function elements and risk control paths in each stage. The system depicts the multi-stage risk factor coupling relation of road hazardous chemical substance transportation, quantitatively identifies the risk transmission path and the key control link, and provides effective technical support for improving the safety of the transportation system.

The invention relates to an intelligent auxiliary monitoring system and method for a transformer substation, and relates to the technical field of power system monitoring, and the system comprises the steps: collecting multi-source heterogeneous data, constructing an equipment dynamic probability state superposition vector, analyzing quantitative data association through cognitive resonance to update the vector and calculate risk entropy, introducing a focusing control module, and carrying out the focusing control. The calculation intensity of the analysis module is dynamically adjusted according to the risk entropy, and efficient utilization of resources is realized while the monitoring sensitivity is ensured; and meanwhile, the system constructs a state evolution path, and performs dynamic time warping matching on the state evolution path and a preset restricted zone topology library to realize prospective evaluation of the risk evolution trend. And finally, an early warning module determines whether to trigger early warning based on a dual-mode criterion formed by a risk entropy absolute value and a path matching result, and generates a structured diagnosis report containing a potential fault mode and traceability evidence. According to the invention, early-stage, efficient and prospective intelligent early warning of latent faults can be realized, and the operation and inspection efficiency is remarkably improved.

The invention discloses a welding quality detection method for a precise heat dissipation tooth-shaped plate, and the method comprises the steps: determining a heat flow feature point on the tooth-shaped plate, and applying a thermal pulse sequence to obtain dynamic thermal response data; performing space-time decomposition on the thermal response data to generate thermal disturbance response fingerprints; applying a preset phase thermal pulse source according to the thermal disturbance response fingerprint to obtain thermal wave interference field data and generate a thermal wave interference defect map; periodic thermal excitation is applied according to the thermal wave interference defect map, a thermal attenuation time constant is obtained, and a resonance thermal attenuation spectrum and a spectrum consistency spatial distribution map are generated; and calculating a thermal defect severity index according to the spectral consistency spatial distribution map and the thermal wave interference defect map, and generating a welding quality evaluation result. According to the technical scheme, direct correlation between the welding quality and the heat dissipation performance can be established through thermal wave interference and thermal resonance analysis, the welding defect which affects the heat conduction efficiency but does not cause obvious structural failure is effectively recognized, and accurate evaluation of the welding quality is achieved.

The present invention relates to a method for analyzing resonance in a wind power grid-connected system. By establishing an impedance model of a direct-drive wind turbine, the resonance problem of the wind power grid-connected system is analyzed, considering the influence law of the DC bus capacitor on the impedance model of the direct-drive wind turbine under the condition of power disturbance on the AC side. In addition, in the process of establishing the impedance model of the direct-drive wind turbine, the harmonic state space theory is used to perform a steady-state processing on the linearized single-phase analytical model. The harmonic state space method can represent multiple frequency responses in each variable at the same time, so as to establish an impedance model of the direct-drive wind turbine with a multi-dimensional harmonic transfer function, which can accurately reflect the influence of the DC bus capacitor or asymmetric control on the impedance characteristics of the direct-drive wind turbine; using this impedance model of the direct-drive wind turbine to analyze the resonance problem of the wind power grid-connected system, since it comprehensively reflects the influence mechanism of the DC bus capacitor on the frequency coupling characteristics of the system, the accuracy of resonance analysis of the wind power grid-connected system can be improved.

The invention relates to the technical field of virtual synchronous generator control systems, in particular to a control system for suppressing VSG synchronous frequency resonance. The control system for suppressing VSG synchronous frequency resonance comprises a frequency detection unit used for monitoring synchronous frequency and phase change of the system in real time and identifying frequency fluctuation. According to the VSG system, the frequency detection unit, the resonance analysis unit and the compensation signal generation unit are arranged, the adaptability and stability of the VSG system in a power network are improved, synchronous frequency resonance is effectively suppressed by accurately monitoring and controlling the synchronous frequency, the quality and safety of power supply are guaranteed, and meanwhile, the service life of the VSG system is prolonged. A safety protection unit is further arranged in the system, potential fault risks can be effectively prevented, the reliability of the whole system is improved, the flexibility of system operation is enhanced through a user interface unit, a user can easily manage and monitor the state of the system, and therefore the satisfaction degree of the user is improved.

The invention discloses a nonlinear bending and forced vibration analysis method for a post-buckling aircraft fluid conveying pipe, and belongs to the technical field of mechanical property analysis of aircraft fluid conveying pipes. The method comprises the following steps: establishing a static dynamic model of the flow-induced post-buckling aircraft flow conveying pipe; a two-step perturbation technology is expanded to a post-buckling equilibrium path, and an initial configuration is provided for bending and resonance analysis; according to the two symmetrical initial bifurcation paths, the two-step perturbation method is adopted again to obtain the bending load-deflection explicit relation; according to the method, a two-step perturbation method and an improved LINDSTED-Poincare method are combined, and an approximate analytical solution of strong nonlinear forced vibration is obtained. According to the method, the nonlinear static dynamic structure design of the aircraft fluid conveying pipe under the combined action of internal fluid flow induced deformation and external loads can be guided.

The present invention provides a coupled resonance analysis method for aircraft fluid pipes transmitting supercritical high-speed pulsating flow under forced excitation, which belongs to the field of aircraft dynamics. Based on the structural model of the aircraft fluid pipe, the present invention establishes a coupled resonance model of the aircraft fluid pipe induced by supercritical pulsating flow, and for the strong nonlinear coupled resonant behavior of the aircraft fluid pipe, establishes the perturbation-incremental harmonic balance method for bifurcation analysis for the first time. Furthermore, a numerical iteration method is used to solve the amplitude-frequency bifurcation relationship under a certain excitation amplitude, and the Floquet theory is used to evaluate the stability. Finally, a database of the excitation parameters and material parameters of the aircraft fluid pipe and the coupled resonance characteristics is constructed. The present invention can effectively analyze the coupled resonance characteristics of the aircraft fluid pipe when transmitting supercritical high-speed pulsating flow under forced excitation, and provides a reliable analysis method and technical support for the design and safe operation of the aircraft fluid pipe.

The invention discloses a safety helmet intelligent control method and system based on electroencephalogram characteristics, and the method comprises the steps: decomposing a real-time electroencephalogram signal frequency spectrum to generate cognitive load frequency domain characteristics, and building an electroencephalogram control space; an electroencephalogram control space is scanned to identify a frequency band coupling unbalance point, a cooperative intervention opportunity is reversely derived, and a multi-channel adjustment mode is formed; mapping the stimulation frequency range to generate a frequency matching domain, and performing resonance analysis to determine a resonance intervention window; monitoring a frequency band in a resonance window to obtain an energy migration track, constructing a risk propagation chain to identify a cascade failure node and forming a key blocking anchor point; analyzing risk acceleration of the key blocking anchor points to form a state deterioration rate, fusing frequency domain features to generate dynamic delay tolerance, and generating variable speed control parameters in a fast-slow grading manner; the variable speed control parameter is compared with a threshold value to generate a control deviation signal, reverse phase modulation is carried out to generate a hedging stimulation waveform, a phase compensation execution instruction is formed, and accurate monitoring and safe intervention of the cognitive state are achieved.

The invention discloses an acoustic emission real-time diagnosis method and an acoustic emission real-time diagnosis system for corrugated board degumming defects, and relates to the technical field of packaging material quality detection. Each group is provided with a class-A sensor located on the interface of the surface paper and the core paper, a class-B sensor located in the core paper and a class-C sensor located on the interface of the core paper and the bottom paper, the class-B sensor is in communication connection with the class-A sensor, the class-C sensor and the diagnosis main station, various sensors collect acoustic emission signals at corresponding positions and give an alarm, and the class-A sensor and the class-C sensor collect the signals and upload the signals to the class-B sensor; the B-type sensor collects internal signals of core paper and receives the A-type signals and the C-type signals, then multi-mode resonance analysis and time-frequency feature extraction are carried out, feature data are sent to the diagnosis master station, the master station dynamically models and analyzes the feature data based on a neural differential equation and judges and locates degumming defects, a signal threshold value is set in advance to assist in judgment, and the degumming defect is determined. Meanwhile, the degumming development trend can be predicted, and accurate real-time diagnosis and positioning are achieved.

This invention discloses an artificial intelligence-based computing platform management system, specifically relating to the field of dynamic allocation technology for distributed storage resources. It addresses the resource allocation oscillation problem caused by hardware performance differences and dynamic degradation in existing technologies. The system employs a real-time acquisition module to obtain the hardware performance, load status, and data paths of storage nodes; an entropy determination module to calculate the path topology entropy and trigger reconstruction instructions; a resonance analysis module to analyze the group correlation strength of hardware performance degradation and mark resonant node groups; a weight generation module to integrate the above parameters to generate dynamically allocated weights; an error compensation module to optimize weight coefficients based on historical error data; and a migration execution module to perform migrations based on the weights and limit the load on resonant nodes. Through the coordinated regulation of topology entropy monitoring and hardware resonance analysis, the system suppresses the spread of local oscillations, reduces unnecessary migration operations, and improves system stability and hardware lifespan.

The application discloses a method for evaluating performance of interlayer composite vibration isolation structure based on vibration feedback, and relates to the technical field of building structure analysis, and comprises the following steps: obtaining mechanical data of the composite vibration isolation structure, generating a first parameter through resonance analysis, and generating a second parameter through classified fault analysis; based on the first parameter, generating a sensor layout set through optimization of sensor layout, and based on the sensor layout set and the second parameter, generating a reinforcement strategy of each sensor layout node through machine learning to form a failure-resistant sensor network; obtaining real-time monitoring data of the failure-resistant sensor network, and obtaining a quantitative evaluation result of vibration isolation performance through transmission rate and boundary state analysis. The application is used to solve the problem of insufficient self-adaptation of the sensor layout strategy in the performance evaluation of the interlayer composite vibration isolation structure.

The invention relates to the technical field of civil aviation operation risk management and control, in particular to a flight full-chain operation situation risk assessment method, which comprises the steps of constructing a full-chain risk event library, determining trigger time, calculating peak time and standard deviation and amplitude of a Gaussian pulse function, and constructing a Gaussian pulse energy representation model of a full-chain risk event. Calculating a link coupling weight and a risk amplification coefficient of the full-chain functional resonance analysis-cascade model coupling network; and calculating the probability that the risk module enters an abnormal state at the next moment according to the risk amplification coefficient, selecting various parameters through Monte Carlo simulation, calculating the total risk energy according to the various parameters and the amplitude after coupling amplification, identifying the link control priority, and outputting the risk level of each operation stage. According to the method, accurate characterization of a full-chain risk event, quantitative calculation of a cross-stage coupling effect and accurate identification of a high-risk link are realized, and pertinence and effectiveness of flight full-process risk management and control are improved.

The invention relates to the technical field of concrete vibration, in particular to a PID fuzzy control system for automatic concrete vibration. The system abnormity identification module determines the credible abnormity weight of each sequence section of each vibrating rod according to the fluctuation characteristic of the vibration signal of the sequence section, the fluctuation difference characteristic of the sequence section and the other sequence sections and the vibration signal of the corresponding motor, and screens out the abnormal sequence section according to the credible abnormity weight; the resonance analysis module is used for determining a resonance risk index according to the distance between the abnormal sequence section and each comparison sequence section and the distance between the abnormal sequence section and the vibrating rod; correcting the credible exception weight by using a resonance risk index to obtain a comprehensive exception weight, and screening out a target exception sequence segment according to the comprehensive exception weight; the control module is used for distributing control weights to the sequence segments of the vibrating rods based on the target abnormal sequence segments and the comprehensive abnormal weights so as to form a control weight sequence; and a feedback signal of fuzzy control is modulated according to the control weight sequence, a vibrating rod adjusting instruction is generated, and therefore uneven concrete quality is avoided.

The present application relates to the technical field of resonance analysis, and in particular to a method and device for evaluating effectiveness of a parallel resonance suppression scheme in a power system. In the present application, a local parallel resonance suppression evaluation index and a non-local parallel resonance suppression evaluation index are constructed, and corresponding feasible regions are constructed, so as to evaluate the parallel resonance suppression effect of a resonance suppression method access node and the effect of parallel resonance of surrounding other nodes. The present application solves the problem that the application scene of a resonance suppression method is limited and the parallel resonance scene is not compatible with the resonance suppression method.

The invention discloses a distributed photovoltaic power distribution network risk assessment method based on function resonance analysis, which comprises the following steps: based on a function resonance theory, key function modules of a power distribution network are identified from four aspects of character management and loop, and each function module is completely defined through a six-element model; based on scene-level driving typical fault backtracking analysis, comprehensive risk indexes of a scene are calculated, and a'node-link-loop-scene 'system integrated risk assessment system is constructed. The method has the beneficial effects that a power distribution network risk propagation mechanism can be divided into a node-level system, a path-level system, a loop-level system and a scene-level system on the basis of the dynamic characteristics of the functional coupling relationship, and the risk of the power distribution network can be evaluated by constructing a'node-link-loop-scene 'four-level risk evaluation system; the accurate analysis of the multi-dimensional risk propagation mechanism of the high-proportion photovoltaic power distribution network is realized.

The invention provides an air resonance modeling and analysis method for a forward-backward swept and up-down reverse blade tip configuration helicopter. The method comprises the following steps: establishing system coordinate systems and a relationship between the coordinate systems; establishing a rotor blade structure dynamic model; establishing a rotor blade aerodynamic model; establishing dynamic and pneumatic models of the blade tip section; establishing an airframe kinetic model; establishing a complex three-dimensional shape rotor wing and fuselage coupling air resonance kinetic equation for derivation; balancing calculation and linearization processing are carried out; and establishing an air resonance analysis method.

The application provides a flexible direct-current (DC) transformer DC bias current calculation method and related device, including obtaining a resonance analysis model of a DC loop of a flexible DC transmission system converter; the resonance analysis model is constructed based on the physical structure of the DC loop of the flexible DC transmission system converter; the impedance at 50Hz in the resonance analysis model is obtained through frequency scanning, and whether the impedance is less than a set threshold; if yes, time domain simulation calculation is performed by using a multi-terminal DC detailed electromagnetic transient simulation model to obtain the DC bias current of the flexible DC transformer; the multi-terminal DC detailed electromagnetic transient simulation model is used for simulating the electromagnetic transient process of the multi-terminal flexible DC transmission system. The DC loop resonance analysis model is constructed to judge the impedance at 50Hz, and then the electromagnetic transient simulation model is used to calculate the DC bias current, so that the DC bias risk of the flexible DC transformer can be effectively evaluated.

The invention provides a coupling resonance analysis method for transmitting supercritical high-speed pulsating flow by an aircraft flow transmission pipe under forced excitation, and belongs to the field of aircraft dynamics. According to the method, a coupling resonance model, induced by the supercritical pulsating flow, of the aircraft fluid conveying pipe is established based on a structural model of the aircraft fluid conveying pipe, and the perturbation-increment harmonic balance method for bifurcation analysis is established for the first time according to the strong nonlinear coupling resonance behavior of the aircraft fluid conveying pipe. Furthermore, an amplitude-frequency bifurcation relationship under a certain excitation amplitude is solved by adopting a numerical iteration method, and the stability is evaluated by utilizing a Floquet theory. And finally, constructing a database of excitation parameters, material parameters and coupling resonance characteristics of the airplane fluid conveying pipe. According to the method, the coupling resonance characteristic of the airplane fluid conveying pipe during transmission of the supercritical high-speed pulsating flow under forced excitation can be effectively analyzed, and a reliable analysis method and technical support are provided for design and safe operation of the airplane fluid conveying pipe.