12 results about "Harmonic excitation" patented technology

This invention relates to the field of nonlinear node detection technology, and particularly to a nonlinear electronic node concealment detection system based on S-band harmonic fingerprinting. The system includes: acquiring fundamental and second harmonic echo signals from multiple detection nodes within the detection area in the S-band to ensure a sufficient data source for the entire detection process; constructing harmonic excitation response features and generating a fingerprint database to improve the accuracy and targeting of subsequent node identification; dynamically capturing the node's current characteristic information by transmitting S-band frequency sweep detection signals and collecting echo harmonic components to extract real-time fingerprints, enhancing the timeliness of node detection; identifying matching concealed electronic nodes by performing multi-dimensional time-series correlation matching between real-time harmonic fingerprints and fingerprints in the fingerprint database, effectively filtering out irrelevant interference; and generating a topology map and marking abnormal nodes, enabling users to quickly grasp the overall situation and rapidly locate anomalies.

The invention relates to a wheel polygon wear suppression method, an inter-harmonic excitation suppression circuit, a method and a medium, and relates to the technical field of railway traction transmission. On the basis of inter-harmonic excitation suppression and polygon wear feedback suppression, the malignant feedback effect caused by electromechanical coupling is weakened, and therefore suppression of polygon wear development of the wheel is achieved; the inter-harmonic excitation suppression comprises the following steps of: arranging an active power filter in a direct current link, and compensating direct current link power fluctuation caused by harmonic waves introduced by a rectifier; the polygon abrasion feedback suppression comprises the steps that compensation current is calculated based on the rotating speed fluctuation quantity under polygon abrasion excitation, and the T-axis current of the motor is compensated. According to the scheme, corresponding technical measures can be put forward from the two aspects of inter-harmonic excitation source suppression and polygon wear feedback suppression, comprehensive suppression of development of polygon wear of the wheel is achieved, polygon wear of the wheel caused by electrical parameters is reduced, and the method has the advantages of being low in implementation cost and not prone to being affected by the external environment.

This invention discloses an electromagnetic coil winding detection system and method, belonging to the field of electromagnetic coil winding technology. It solves the problem in segmented electromagnetic coil windings of high-voltage high-frequency transformers where distributed parameter resonance and high-frequency harmonic coupling generate dynamic interlayer overvoltages, continuously inducing partial discharges, ultimately leading to winding breakdown and short circuits, and the cause of failure is difficult to trace. The system includes a data acquisition module, a data preprocessing module, a resonance feature extraction module, a parameter calculation module, a risk index calculation module, a product-level judgment module, and a batch statistical process control module. This invention collects impedance data of the electromagnetic coil at multiple frequency points and preprocesses it to extract resonance feature parameters. It then calculates the resonance amplification factor and harmonic excitation intensity by combining operating parameters, and further integrates the quality factor and frequency matching degree to generate a comprehensive risk index. Based on this index, the coil is graded, and batch data is statistically controlled to issue process warnings.

This invention provides a transformer loss detection method based on CNN-BiLSTM and SFG, belonging to the field of transformer technology. This invention establishes a finite element simulation model of a converter transformer, including harmonic excitation and DC bias conditions, using the SFG adaptive sparse mesh partitioning algorithm. It generates a training dataset of three-phase voltage and current waveforms and magnetic field loss temperature distribution. A physical constraint model is constructed, integrating a CNN feature extraction layer, a BiLSTM time-dependent layer, and Joule's law constraint terms embedded in Maxwell's equations for heat conduction. The model outputs predicted loss results using real-time acquired measured three-phase voltage and current waveforms as input, and sends adjustment commands to the monitoring system or cooling control system based on the loss difference. This solves the technical problem of difficulty in real-time and accurate detection of the loss state during converter transformer operation.

This disclosure provides a method for manufacturing a rubber roller in a printing system and a printing system thereof. The method for manufacturing the rubber roller in the printing system includes: establishing a finite element analysis model of the rubber roller; determining the natural frequencies and mode shapes of the rubber roller based on the finite element analysis model; performing frequency response analysis based on the natural frequencies to obtain frequency response results under harmonic excitation; using the frequency response results to at least determine weak regions of the rubber roller that do not meet performance conditions; constructing dynamic equations based on the frequency response results and mode shapes, and obtaining the dynamic characteristics of the rubber roller based on the dynamic equations; constructing a topology optimization model and constraints based on the dynamic characteristics; optimizing the parameters of the rubber roller through iterative calculation of the topology optimization model based on the constraints to obtain optimized parameters; and manufacturing the rubber roller according to the optimized parameters.

The invention relates to the technical field of intelligent optimization of structural parameters of dampers of wind power generation equipment, and discloses an intelligent optimization design method for parameters of an offshore wind power damper. A damping coefficient, a rigidity coefficient and a piston stroke form a parameter vector, an upper bound and a lower bound are set, an input amplitude, frequency and an initial phase are recorded according to a harmonic sequence number, and multi-harmonic excitation is established. Enabling the device to be equivalent to a single degree of freedom, calculating the steady-state amplitude and phase difference of each order, and forming frequency-amplitude mapping; setting a unified target amplitude and being constrained by a stroke, and constructing frequency domain measurement based on full-order deviation square; calculating damping and rigidity gradients of the measurement to form vectors, performing updating, boundary and stroke projection, closed correction and resonance rejection in combination with the minimum step pitch and the threshold value, and defining minimum distinguishable change and convergence by tolerance; recalculating the step length and projection for the overrun order, and lowering the target when necessary; and finally, through step-by-step energy balance checking, outputting optimal damping, rigidity and stroke recorded values and a full-order response table.

The invention discloses a towed linear array vibration isolation module bidirectional fluid-solid coupling simulation method. The method comprises the following steps: constructing a finite element structure model of a vibration isolation module; calculating a viscous damping coefficient for an equivalent fluid damping effect; inserting and configuring a spring element with the damping coefficient between adjacent components in the model; performing grid division on the model; applying pretension force for statics analysis; applying simple harmonic excitation based on a static analysis result to perform harmonic response analysis; and extracting vibration responses of the input end and the output end, and calculating a vibration isolation quantity frequency spectrum. Complex fluid domain modeling and calculation in traditional bidirectional fluid-solid coupling are equivalently simplified into setting of a parameterized damping spring in a pure structure model, so that the simulation calculation time is greatly shortened from the hour level to the minute level on the premise that the calculation precision is kept (the average error is about 2.74 dB compared with that of a classical method), and the simulation calculation efficiency is greatly improved. The calculation efficiency is obviously improved; and the resource consumption is reduced.

The invention provides a marginal plate damping device optimization method based on Monte Carlo simulation and Latin hypercube design, and the method comprises the steps: selecting a certain order of vibration mode of a blade mode to carry out the structure optimization design of a damper based on the vibration mode of the blade mode, and determining the harmonic response frequency range of the blade; processing a blade group substructure by a dual-mode synthesis method, and combining an overall structure matrix through a substructure reduction matrix; obtaining a parameter matrix and a two-dimensional contact surface friction model, and constructing a dynamic equation set with dry friction nonlinearity; a dynamic equation set with dry friction nonlinearity is obtained, and an amplitude-frequency characteristic curve is solved through a harmonic balance method and an arc length continuation method; monte Carlo simulation and Latin hypercube design are carried out, a multi-parameter Monte Carlo simulation analysis program is written, and parameter optimization analysis with the optimal damping effect of the damping device as the target is completed; and obtaining an optimal parameter group to further optimize the original damping structure. The model is processed through a substructure method, and the vibration response of the blade group with dry friction damping under simple harmonic excitation can be predicted.

This invention discloses a vibrating screening device for adjustable coal slurry particle size distribution, relating to the field of coal slurry screening technology. It includes: a segmented screen box, the interior of which is divided into at least two vibration zones along the coal slurry flow direction; a screening component disposed within each vibration zone, the screening component being adjustable in terms of particle size; an excitation system disposed on the segmented screen box, the excitation system being used to apply independently adjustable harmonic excitation to each vibration zone; a feed hopper disposed above the feed end of the segmented screen box; and a microbubble generating component disposed inside the feed hopper, injecting microbubbles into the coal slurry. This invention possesses significant advantages such as multi-zone heterogeneous vibration, stepless orifice adjustment for coal slurry particle size, and microbubble anti-clogging and screen cleaning, significantly improving the separation efficiency of coarse and fine particles and meeting the need for refined adjustment of coal slurry particle size distribution under different working conditions.

The invention discloses a multi-harmonic excitation optimization method and system based on an improved genetic algorithm, and relates to the technical field of motor driving and control, and the method comprises the steps: obtaining a function relation between the total excitation current of a multi-phase self-excitation synchronous motor and the amplitude of each harmonic current; establishing an optimization model with excitation current maximization as a target based on the function relationship; creating an initial population based on the proportionality coefficient of each harmonic current amplitude; obtaining a fitness value of each individual based on the initial population and the optimization model; performing selection, crossover and variation on the individuals based on the fitness values to obtain an updated population; circulating the obtained fitness values on the basis of the updated population, and performing selection, crossover and variation until a termination condition is met, thereby obtaining an optimal population; and obtaining an optimal proportionality coefficient based on the optimal population. Cooperative optimization improvement of the excitation current and the output torque is realized, so that the excitation capability and the torque output of the motor in a medium-high speed area are improved.

The application discloses a kind of based on sideband harmonic excitation's double-unit motor modal parameter identification method, belong to motor field.This method includes selecting the sideband harmonic current of preset frequency as vibration excitation source;Select the maximum speed of sideband harmonic current as test speed;Switching frequency sweep is carried out to double-unit motor to be measured, and the vibration acceleration data of each test point is obtained;Different phase shift angles are used to carry out carrier phase shift processing to sideband harmonic, and the vibration acceleration data of each test point in different order is obtained by repeating test step;Select multiple suspicious resonance points from vibration acceleration data;According to corresponding vibration acceleration data, mode shape analysis is carried out, and the spatial mode shape, vibration order and natural frequency of real resonance point are confirmed;According to real resonance point, frequency response function is constructed, and the modal parameter of double-unit motor to be measured is extracted from it.The modal parameter identification of low cost, high excitation energy and wide frequency range is realized.

The invention relates to the technical field of intelligent manufacturing and testing of charging piles, and discloses a charging pile production test data acquisition and analysis method and system.The charging pile production test data acquisition and analysis system comprises the steps that high-sampling-rate current waveform data and multi-sensor abnormal event records of a charging pile under different load conditions are acquired, and the data of the high-sampling-rate current waveform data and the multi-sensor abnormal event records are acquired; generating a time-aligned multi-modal data sequence; grouping the abnormal events based on a density clustering algorithm, and outputting an abnormal event clustering result; generating a harmonic trigger probability graph based on historical data statistics; inputting the real-time harmonic fingerprint vector into a probability graph for matching, and calculating a fault triggering probability value in a current state; and based on Bayesian reasoning, fusing the fault probability of the multi-dimensional harmonic characteristics, and outputting a power module hidden defect risk level and an early warning signal. According to the invention, the hidden defect that the charging pile power module is exposed only under the excitation of the specific harmonic wave can be effectively identified, and the early warning of the intermittent fault is realized.