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58 results about "Electromagnetic model" patented technology

Electromagnetic Modeling. Electromagnetic modeling is the process of solving Maxwell’s equations to precisely determine electric fields, magnetic fields, and currents.

Multi-scattering SAR imaging simulation method, system and device based on physical consistency modeling and medium

The invention discloses a multi-scattering SAR (Synthetic Aperture Radar) imaging simulation method, system and device based on physical consistency modeling and a medium. The method comprises the following steps: constructing a three-dimensional electromagnetic model of a target; constructing a geometric model under the working mode of the ray tracing auxiliary transmitting-receiving co-located SAR; a high-frequency electromagnetic scattering algorithm based on ray tracing is adopted, multiple scattering paths of a first order, a second order and a higher order are considered, superposition and amplitude modulation are carried out on scattering contributions of all orders, scattering field distribution of a target under the far field condition is calculated, and a far-field scattering field is obtained; performing spatial propagation mapping on the total far-field scattering field, and mapping a far-field scattering result into a radar platform near-field echo signal; correcting the amplitude of the echo signal to obtain a two-dimensional SAR near-field echo matrix; sAR imaging processing is carried out, wherein the SAR imaging processing comprises distance compression, range migration correction (RCMC) and azimuth compression. According to the invention, the authenticity and precision of SAR imaging simulation in a complex target scene are improved.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Aluminum pipe local conductivity regulation and control method, system and equipment based on dynamic electromagnetic field modulation and medium

The invention relates to an aluminum pipe local conduction regulation and control method, system and device based on dynamic electromagnetic field modulation and a medium, and the method comprises the steps: driving an electromagnetic coupling array to scan a target conduction region of an aluminum pipe, so as to construct a three-dimensional dynamic electromagnetic model; analyzing and generating a multi-band excitation parameter combination in a bandwidth constraint range according to the target conductivity gradient parameter; the method comprises the following steps: driving an electromagnetic coupling array by a multi-band excitation parameter combination, collecting an electromagnetic response spectrum of a target conductive area in real time, extracting an eddy current characteristic component set, calculating an obtained phase compensation amount, and dynamically adjusting an excitation phase difference and a power ratio of the electromagnetic coupling array to form a controllable standing wave interference field; and solving the Lyapunov function gradient difference between the node distribution characteristics of the standing wave interference field and the predicted value of the three-dimensional dynamic electromagnetic model so as to iteratively update the multi-band excitation parameter combination. According to the invention, high-precision dynamic regulation and control of the conductivity gradient of the aluminum tube are realized, the energy consumption is effectively reduced, and the stability of a standing wave interference field is enhanced.
Owner:CHANGSHA HENGJIA ALUMINUM CO LTD

Modeling optimization method for biconical antenna balun equivalent circuit based on multi-conductor transmission line

The invention discloses a biconical antenna balun equivalent circuit modeling optimization method based on a multi-conductor transmission line, and belongs to the technical field of electromagnetic simulation. The method comprises the following steps: firstly, establishing a three-dimensional electromagnetic model of a biconical antenna balun based on a finite element method, and setting ports and defining boundary conditions in combination with an actual current transmission path; then, distribution parameters among conductors are extracted through a multi-conductor transmission line theory, and a Balun circuit topological structure is constructed; and finally, taking the antenna coefficient as an optimization target, carrying out iterative optimization on equivalent circuit element parameters by adopting a multi-target genetic algorithm, considering a plurality of optimization targets in a broadband range, and finally obtaining a high-precision equivalent circuit model. Through combination of electromagnetic simulation and an intelligent optimization algorithm, high-efficiency extraction of complex Balun structure distribution parameters and adaptive optimization of circuit parameters are realized, and the simulation precision of the biconical antenna is remarkably improved.
Owner:THE 54TH RESEARCH INSTITUTE OF CHINA ELECTRONICS TECHNOLOGY GROUP CORPORATION

Multi-task electromagnetic model based on hybrid expert network

The invention discloses a multi-task electromagnetic model based on a hybrid expert network, and belongs to a wireless communication technology. The model comprises a preprocessing module, a feature extraction module, a task output module and a pre-training-fine tuning learning strategy. The preprocessing module carries out standardization processing on the multi-source electromagnetic signals; the feature extraction module is based on a Transform structure, introduces a hybrid expert network to replace part of a traditional feedforward neural network, and dynamically selects an expert sub-network through a task specific routing mechanism; the task output module configures a special structure according to different task targets; in the pre-training stage, a mask auto-encoder is used for pre-training large-scale label-free data, and a downstream task is subjected to full-amount fine adjustment through small-scale label data. According to the method, multi-task collaborative learning and differential expression are realized, and the recognition performance, robustness and processing efficiency of the model in a complex electromagnetic environment are improved.
Owner:SHANGHAI UNIV

Three-dimensional magnetotelluric forward modeling method and device, medium and equipment

The invention discloses a three-dimensional magnetotelluric forward modeling method and device, a medium and equipment, and relates to the technical field of geophysics, and the method comprises the steps: generating a three-dimensional magnetotelluric model according with an actual field geoelectrical structure based on a Gaussian random field; performing multiple down-sampling operations on the three-dimensional magnetotelluric model to extract semantic features of different scales and semantic levels, and obtaining a low-level feature map according to the semantic features; by introducing a space attention fusion mechanism, distributing different weights to different space regions in the low-layer feature map, and generating a weighted feature map corresponding to the resistivity abnormal region; and performing multiple up-sampling operations on the low-layer feature map to determine a high-layer feature map, fusing the high-layer feature map obtained by each up-sampling operation with the weighted feature map with the same scale to determine a fused feature map, and obtaining a predicted value of the forward modeling response data according to the fused feature map.
Owner:JIANGXI UNIV OF SCI & TECH +2

Multi-power-supply system broadband oscillation risk test and evaluation method

The invention relates to the field of power systems, in particular to a multi-power-supply system broadband oscillation risk testing and evaluating method. The method comprises the following steps: accessing a new energy physical controller to a semi-physical simulation platform, injecting a sweep frequency voltage disturbance signal, and collecting the signal to generate a semi-physical three-dimensional impedance matrix; constructing a corresponding single-machine electromagnetic model in electromagnetic transient simulation software, and injecting sweep-frequency voltage disturbance to generate a single-machine impedance characteristic curve; comparing the two, and correcting electromagnetic model control parameters according to a deviation frequency band; and finally, combining the corrected models and the like, injecting a sweep frequency disturbance signal at a grid-connected point, obtaining impedance, and evaluating the oscillation risk according to a Nyquist stability criterion. According to the method, a semi-physical simulation platform and electromagnetic transient simulation software are combined, impedance scanning is carried out on a physical controller, comparison verification and parameter correction are carried out on the physical controller and an electromagnetic model, the problem of large difference between the model and an actual system is effectively solved, and the accuracy and reliability of broadband oscillation risk assessment are remarkably improved.
Owner:STATE GRID HEBEI ENERGY TECH SERVICE CO LTD +1

An Electromagnetic Field Modeling and Separation Method for Monitoring Ocean Wave Characteristics

ActiveCN121167140BSea wavesAcoustics
This invention belongs to the field of ocean wave characteristic monitoring technology, specifically relating to an electromagnetic field modeling and separation method for ocean wave characteristic monitoring. The method includes: performing Proni decomposition on a noise-interferenced ocean wave-induced electromagnetic field signal ( ) to obtain multiple Proni components, and calculating their amplitude, frequency, and attenuation factor; filtering the Proni components according to preset constraints to obtain filtered Proni components; removing repetition frequencies from the filtered Proni components to obtain effective signal components; establishing a sinusoidal signal and calculating its cross-correlation sequence with ( ), finding the peak position in the sequence to obtain the phase of the effective signal components; and constructing an ocean wave-induced electromagnetic model based on the frequency, amplitude, and phase of the effective signal components to obtain a clean ocean wave-induced electromagnetic field signal ( ). This invention can better separate the ocean wave-induced electromagnetic field from noise, solving the problem of difficulty in analyzing ocean wave dynamics characteristics due to noise interference.
Owner:OCEAN UNIV OF CHINA

Rapid inversion method based on radar electromagnetic model in high-cold and high-altitude geological environment

The invention discloses a rapid inversion method based on a radar electromagnetic model in a high-cold and high-altitude geological environment, and the core idea of the method is that a two-parameter wave field forward modeling model is constructed based on a Maxwell electromagnetic field equation, a time window-based convolution type objective function is utilized, and a real source function is not needed. Source-independent full-waveform inversion of single-offset GPR data is realized, an SVD method is introduced to automatically extract a reference waveform and determine the length of a time window, direct wave and reflected wave information is effectively separated, and the inversion calculation overhead is remarkably reduced in cooperation with a multi-scale frequency and random sub-source sampling strategy. According to the method, high-precision reconstruction can be performed on the underground dielectric constant and the conductivity on the premise that accurate source waveforms are not needed, and the practicability and the real-time performance of plateau area non-contact radar detection are remarkably improved.
Owner:HARBIN INST OF TECH

Integrated linear servo joint thermal power magnetic multi-physics field coupling design method based on Ansys Workbench

PendingCN121960333ASolve the problem of decreased joint performanceReduce trial and errorDesign optimisation/simulationSpecial data processing applicationsHeat fluxRoller screw
The invention relates to the technical field of mechanical transmission and mechatronics, in particular to an integrated linear servo joint thermal magnetic multi-physics coupling design method based on Ansys Workbench, which comprises the following steps: establishing a three-dimensional model of a reverse planetary roller screw; constructing an electromagnetic model of the motor, and performing electromagnetic simulation; internal heat and convective heat transfer coefficients corresponding to the motor are obtained; the heat flow, the heat flux and the convective heat transfer coefficient corresponding to the reverse planetary roller screw are obtained; and constructing a thermal magnetic coupling model, and performing simulation solution. According to the method, the heat, force and magnetic multi-physical field coupling effect is comprehensively considered in the integrated linear servo joint, and the problem that the overall performance of the whole joint is reduced due to the fact that the temperature is too high due to improper design is effectively solved.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Axial flux motor NVH simulation analysis method and system

PendingCN122508806AImprove simulation accuracyOvercoming excitation distortion problemsElement modelElectric machine
The application discloses an NVH simulation analysis method and system of an axial flux motor, and relates to the technical field of motor NVH simulation.The method provided by the application comprises the following steps: a three-dimensional finite element model of the axial flux motor is established; a three-dimensional electromagnetic model comprising at least one periodic structural unit is established; first node electromagnetic excitation of a first stator on the periodic structural unit is extracted based on the three-dimensional electromagnetic model; complete electromagnetic excitation covering the first stator and a second stator is generated and loaded to the three-dimensional finite element model by performing spatial transformation on the first node electromagnetic excitation, including a rotation replication operation based on circumferential periodicity and a symmetric mapping operation based on double-stator symmetry; and finally, coupling calculation is performed to obtain NVH response parameters.The application significantly improves the accuracy of simulation analysis by using an accurate excitation loading mode, and provides a reliable basis for the optimization of the NVH performance of the motor.
Owner:ZHIXIN TECH CO LTD

Characteristic mode design system for broadband conformal antennas used in inspection

This invention relates to the field of urban rail transit inspection technology, and particularly to a characteristic mode design system for broadband conformal antennas used in inspection. The system includes an inspection condition parameter input module for acquiring the condition parameters of the target inspection section, which at least include the section type, communication link requirements, and target operating frequency band; a multi-rotor UAV body modeling module for establishing a full-size three-dimensional electromagnetic model of the UAV based on its geometry and material properties; and a characteristic mode analysis module, signal-connected to the inspection condition parameter input module, for analyzing the characteristic modes based on the target operating frequency band. This invention deeply integrates inspection condition parameters into the entire process of characteristic mode selection, antenna element design, and beamforming. Based on the communication link requirements of different inspection sections, it selects matching dominant characteristic modes and implements targeted beamforming, ensuring that the antenna radiation characteristics are highly adapted to the complex inspection environment of rail transit and overcoming communication attenuation problems.
Owner:CHONGQING TECH & BUSINESS INST

A quick electromagnetic-thermal coupling optimization design method for permanent magnet motor considering demagnetization

This invention discloses a rapid electromagnetic-thermal coupling optimization method for permanent magnet motors considering demagnetization. Specifically, it involves finding an initial topology for the permanent magnet motor that satisfies the temperature rise condition after electromagnetic-thermal coupling calculations, and obtaining the average temperature rise of each component of the motor. This temperature rise is then fixed in the parametric electromagnetic model of the motor, and the motor efficiency is calculated using LHS sampling and finite element method. or With the degree of demagnetization D m Furthermore, a demagnetization penalty term is introduced into the efficiency calculation. D m Mapped to a 01 array, denoted as D m_01 Using efficiency data and demagnetization data D m_01 The Kriging response surface and the decision tree response surface were trained separately. Using demagnetization as a constraint, the motor efficiency was optimized and validated using NAGA-II. If the accuracy of the efficiency response surface was insufficient, it was trained and optimized again to enhance its predictive ability in the high-efficiency region of the motor. Electromagnetic-thermal coupling calculations were performed using the highest-efficiency topology predicted by the efficiency response surface to obtain the efficiency. or re .like or re If the requirements are met, the optimization ends; if not, a new round of optimization begins, and this cycle continues.
Owner:SOUTHEAST UNIV

A method, device, equipment and medium for monitoring temperature of a converter transformer winding

The application discloses a kind of converter transformer winding temperature monitoring method, device, equipment and medium, it is related to power transformer technical field, comprising the following steps: establishing the two-dimensional equivalent electromagnetic model of converter transformer, and electromagnetic simulation is carried out, obtain winding loss;Winding loss is as the heat source of two-dimensional flow-temperature field of two-dimensional equivalent flow-temperature model to two-dimensional equivalent flow-temperature model carries out fluid-temperature field simulation;With inlet oil temperature, inlet flow and ambient temperature as input variable, net side hot spot temperature, net side average temperature, valve side hot spot temperature and valve side average temperature as output value, construct linear regression model;Fine tuning model is constructed, linear regression model is combined with fine tuning model, obtain hybrid model.The application is with multiple independent variables as input, with winding hot spot and average temperature as output to establish the basic model based on linear regression and the fine tuning model with the error of winding hot spot and average temperature as output, and the two are combined to obtain hybrid model, the output result of the hybrid model can be with higher precision approximate simulation result, greatly improve the precision of winding temperature calculation.
Owner:CONSTR BRANCH OF STATE GRID JIANGSU ELECTRIC POWER CO LTD

Electromagnetic simulation power transmission line modeling method and system considering traveling wave transmission and step length

The invention relates to the technical field of power systems and automation thereof, in particular to an electromagnetic simulation power transmission line modeling method and system considering traveling wave transmission and step length, and the method comprises the steps: analyzing electromechanical simulation data, recognizing a line element model and parameters, and carrying out the line parameter inspection and loss complementation, thereby obtaining the relation between equipment elements of a power transmission line and a topology; the method comprises the following steps: selecting an integral step length according to an electromagnetic simulation requirement of a power system, and selecting a proper electromagnetic simulation line model by considering traveling wave transmission and the integral step length according to a traveling wave transmission speed and a line length on the basis of ensuring simulation precision and efficiency; electromechanical and electromagnetic model parameters of the line equipment are analyzed, electromechanical model data are automatically converted into electromagnetic model data, and efficient conversion from an electromechanical model to an electromagnetic model is achieved by automatically generating electromagnetic simulation model data; the precision and efficiency of electromagnetic simulation modeling of the power system are improved, and the simulation requirements of a large-scale power system are met.
Owner:STATE GRID ELECTRIC POWER RES INST +3

Welding type IGBT bonding wire space three-dimensional magnetic field distribution calculation method based on forward modeling

The invention relates to a welding type IGBT bonding wire space three-dimensional magnetic field distribution calculation method based on forward modeling, and belongs to the field of power semiconductor devices, and the method comprises the following steps: S1, obtaining welding type IGBT module data, and setting each parameter; s2, carrying out bonding wire geometric preprocessing and wire element discretization; s3, calculating a forward modeling magnetic field; and S4, sorting the magnetic field results at the observation points to generate magnetic field distribution. According to the method, the magnetic field forward modeling model is established based on the three-dimensional space geometric path of the bonding wire, the bending form, the lifting height and the space trend of the bonding wire are directly introduced, errors caused by simplifying the bonding wire into a two-dimensional conductor or an equivalent linear model are avoided, and the space non-uniform distribution characteristics of the magnetic field around the bonding wire are described more accurately; compared with finite element electromagnetic simulation depending on a large number of grid division, the forward modeling calculation method based on the analysis electromagnetic model has the advantages that the calculation process is clearer, and the method is suitable for rapid calculation and comparative analysis of different bonding wire structures.
Owner:CHONGQING UNIV

Calculation method for reducing armoring loss of three-core submarine cable

The invention relates to a calculation method for reducing armoring loss of a three-core submarine cable. Aiming at the problem of loss overestimation caused by neglecting three-phase conductor magnetic field offset and spiral magnetic field influence in a traditional calculation method, the method is based on a double-coordinate system electromagnetic model, analyzes magnetic field distribution inside and outside a conductor through a Maxwell equation set, and deduces and corrects formulas of a metal sheath loss factor lambda1 and an armoring loss factor lambda2. The inhibition effect of eddy current coupling of the armoring layer and the shielding layer, magnetic field distribution of the spiral twisting structure and the same-direction twisting technology on loss is comprehensively considered; meanwhile, the mechanism that the armored steel wire and the conductor are twisted in the same direction to reduce hysteresis and eddy-current loss is disclosed. The method can effectively improve the design precision of the submarine cable current-carrying capacity by optimizing the calculation model and the process parameters, reduces the material consumption, and is suitable for the scenes with high requirements on the economical efficiency and reliability of the cable, such as offshore wind power.
Owner:NINGBO ORIENT WIRES & CABLES CO LTD

Electromagnetic simulation method and system, electronic equipment and storage medium

The invention discloses an electromagnetic simulation method and system, electronic equipment and a storage medium. The method comprises the following steps: establishing an electromagnetic simulation reference model, and training an improved Autoformer model to learn and simulate physical behaviors of a traditional absorption boundary; the method comprises the following steps of: constructing an electromagnetic model to be simulated, setting a computational domain and simulation parameters of the electromagnetic model, and constructing an absorption boundary which is only formed by a single-layer grid and is driven by an improved Autoformer model at a truncation position of the computational domain, so that the absorption boundary is updated without traditional convolution operation and auxiliary field quantity calculation; according to the method, a convolution complete matching layer is replaced in a traditional mixed implicit-explicit time domain finite difference method, for simulation of a complex electromagnetic scene with a one-way fine structure, a variable time step length or multi-metal scattering and the like, a high wave absorption effect is achieved, the implementation process is greatly simplified, the memory overhead is remarkably reduced, and the simulation efficiency is improved. And the overall calculation efficiency is effectively improved.
Owner:HANGZHOU DIANZI UNIV

Assessment result determination method and device, storage medium and electronic equipment

The invention discloses an evaluation result determination method and device, a storage medium and electronic equipment, and relates to the technical field of servers, and the method comprises the steps: segmenting a signal network needing to be analyzed from a target design file imported into preset modeling software; establishing a three-dimensional electromagnetic model of the signal network through preset modeling software, and obtaining a parameter document of the signal network output by the preset modeling software based on the three-dimensional electromagnetic model; building a simulation circuit project of the signal network based on the parameter document through active time domain analysis software, so as to obtain an eye diagram evaluation waveform of the signal network through the simulation circuit project; and determining an evaluation result of the signal quality of the signal network through the eye pattern evaluation waveform. According to the method and the device, the problem that in the design of a high-speed server mainboard, link risk estimation can only be carried out on a signal network in a single transmission direction, and the coupling crosstalk influence in the opposite transmission direction cannot be considered is solved.
Owner:SHANDONG ZHISUO INFORMATION TECHNOLOGY CO LTD

A method for optimizing design of a stator and a rotor of a permanent magnet synchronous motor and the permanent magnet synchronous motor

This application provides a stator and rotor optimization design method for a permanent magnet synchronous motor, including: Step S1, establishing a parametric electromagnetic model based on the main dimensions and performance targets of the permanent magnet synchronous motor, and selecting key design variables; Step S2: conducting orthogonal experimental design on the key design variables based on the Taguchi method, and using finite element simulation to obtain the motor efficiency, average torque, and torque ripple coefficient under different parameter combinations; Step S3: refining the rotor structure based on the motor basic design established by the optimal parameter combination; Step S4: performing mechanical strength verification at the highest operating speed and thermal performance verification under rated operating conditions; Step S5: generating an efficiency characteristic spectrum of the motor within the full operating range and outputting manufacturing drawings. This application, through this method, ensures that the motor achieves a comprehensive performance of high efficiency and low vibration and noise while meeting strict dimensional constraints.
Owner:HEFEI SUFAN AUTOMOTIVE TECH CO LTD

Pulse excitation-oriented cable coupling S parameter general module simulation modeling method

The invention relates to the technical field of electromagnetic compatibility (EMC) test and simulation, in particular to a cable coupling S parameter general module simulation modeling method facing pulse excitation, which comprises the following steps: S parameter module generation stage: utilizing three-dimensional electromagnetic simulation software, and according to a real cable geometric structure, a type and an injection probe model, generating an S parameter module; constructing a cable coupling pulse interference electromagnetic model, and executing frequency domain simulation through a user-defined port and a frequency scanning range to obtain an S parameter module; in the S parameter module simulation application stage, the S parameter module is imported into any circuit simulation software supporting the standard, the S parameter module, a pulse interference excitation source, a terminal load circuit and a tested object circuit model jointly form a complete simulation model, then transient time domain simulation is executed, a detailed response waveform is generated on a tested object port, and therefore performance evaluation is conducted; the method is based on a cross-platform universal interface of an open standard, has wide applicability and prospective verification capability, and shortens the product research and development cycle.
Owner:XIAN XICE ELECTRONICS TECH SERVICE

Electromagnetic field prediction method based on deep learning network model

The invention discloses an electromagnetic field prediction method based on a deep learning network model, belongs to the technical field of calculation of absorption boundaries in electromagnetics, constructs and trains an Autoformer model, applies a sequence decomposition mechanism and a sparse autocorrelation mechanism to a WCS-FDTD framework based on an electromagnetic model so as to update electromagnetic field data more quickly and accurately, and improves the accuracy of the electromagnetic field prediction. And inputting the obtained historical internal field domain and the electromagnetic field data at the corresponding absorption boundary into a trained neural network model for prediction, and calculating the electromagnetic field data of the internal field domain at the next moment based on the predicted electromagnetic field data at the absorption boundary at the next moment and the electromagnetic field data of the internal field domain at the current moment. And combining the obtained predicted value of the electromagnetic field data at the absorption boundary corresponding to the next moment with the electromagnetic field data of the internal field domain at the next moment, generating input data at the next moment, carrying out iterative prediction, and finally obtaining the electromagnetic field data of the computational domain at each moment.
Owner:HANGZHOU DIANZI UNIV

Sensorless model prediction speed control method for synchronous reluctance motor

The invention discloses a sensorless model prediction speed control method for a synchronous reluctance motor. The method comprises the following steps: firstly, establishing a mathematical model of the synchronous reluctance motor; then constructing a model reference adaptive system; an improved adaptive law combining mechanical and electromagnetic models is constructed; and deducing a linearization model, and performing linearization approximation on the IAL-MRAS error system containing a nonlinear feedback link near a working point to obtain the linearization model and a transfer function of the IAL-MRAS error system. And finally, establishing a prediction model to obtain a stator current prediction value and a flux linkage prediction value, and performing switching vector optimization through a cost function. By systematically improving the speed / position estimator, the dynamic performance of sensorless driving of the synchronous reluctance motor is improved.
Owner:XIAN UNIV OF TECH

An Electromechanical-Electromagnetic Adaptive Co-modeling Method for Wind Turbines

This invention discloses an electromechanical-electromagnetic adaptive collaborative modeling method for wind turbine generators, belonging to the field of wind power engineering technology. The method includes: obtaining an initial model / model combination from a pre-constructed multi-precision model library based on the simulation objective; wherein the multi-precision model library includes electromechanical models, electromagnetic models, and hybrid models of electromechanical and electromagnetic models; and, based on the initial model / model combination, using the Lüpertzfox optimization algorithm, obtaining the model / model combination most suitable for the simulation objective from the pre-constructed multi-precision model library. This invention overcomes the shortcomings of traditional wind turbine generator modeling methods, such as fixed modeling accuracy and simplistic models.
Owner:HUANENG POWER INT ENERGY DEV CO LTD +2

An h-adaptive moment method applied to electromagnetic scattering

The application discloses an h-adaptive moment method applied to electromagnetic scattering, and comprises the following steps: an electromagnetic model for calculating scattering characteristics of a to-be-measured target is created, and initial mesh division under plane wave excitation is carried out; current coefficients of each grid element at present are solved by using a moment method based on RWG base functions, and then surface charge density at a super-convergent point in the corresponding grid element is calculated; local errors of the corresponding grid element are calculated based on the surface charge density at the super-convergent point in each grid element and a super-convergent point recovery method; global errors are calculated based on the local errors of each grid element; whether an iteration stopping condition is met is judged; if not, mesh refinement is carried out on some grid elements based on a B-W interpolation point algorithm, re-divided grids are obtained, and the current coefficient solving step is returned; if yes, iteration is stopped, and the current solved current coefficient is output. The application can guarantee calculation precision, robustness, reduce error estimation, reduce the number of mesh refinement and reduce the consumption of calculation resources.
Owner:XIDIAN UNIV +1

A train interference analysis method and device and a storage medium

The application discloses a train interference analysis method and device and a storage medium, and relates to the field of train interference analysis. In the scheme, the complex permittivity under different frequencies is measured in advance to obtain a corresponding relationship between the complex permittivity and the frequency, so that when electromagnetic analysis is performed on the whole train, the target complex permittivity corresponding to the current simulation frequency in the corresponding relationship is used instead of the complex permittivity provided in the existing literature, thereby avoiding the problem that the cited complex permittivity cannot be verified. Furthermore, the accuracy of electromagnetic testing on the whole train is higher by using the pre-measured complex permittivity. In addition, when electromagnetic analysis is performed on the whole train in the application, an electromagnetic simulation model is established, which is an entity simulation model based on the vehicle body structure. Compared with the simplified electromagnetic model commonly used in the prior art, the simulation result obtained is closer to the actual application scenario, so that the reference significance of the simulation result is greater and the value is higher.
Owner:CRRC QINGDAO SIFANG CO LTD

A method of coating a honeycomb array with an additional metal backing to make it electromagnetically parameter equivalent

The application provides an electromagnetic parameter equivalent method for a coated honeycomb composite material array with a metal backing, and relates to the field of electromagnetic calculation. The method comprises the following steps: S1, constructing a unit model and extracting S parameters; S2, constructing a relationship formula of reflection coefficients S 11 and input impedance Z in under TE and TM polarized waves, and calculating the input impedance; S3, inverting to obtain anisotropic equivalent permittivity and permeability; S4, performing phase compensation to obtain corrected anisotropic equivalent permittivity and permeability, and completing an anisotropic equivalent electromagnetic model of the coated honeycomb composite material array with the metal backing. The method of the application can equivalently convert the coated honeycomb composite material into an anisotropic uniform medium, and has good precision under multi-angle, wide frequency band and multi-polarization.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Method and system for calculating loss of large iron-based superconducting metal insulation coil

The invention discloses a large iron-based superconducting metal insulation coil loss calculation method and system, belongs to the technical field of large high-temperature superconducting magnets, and solves the problem of how to improve the efficiency and precision of large iron-based superconducting metal insulation coil loss calculation. Comprising the following steps: solving radial current distribution and a nonlinear magnetic field change rule of a metal insulation coil in excitation and demagnetization processes by adopting an equivalent circuit method, establishing a fine electromagnetic model of the iron-based superconducting tape, and inputting the fine electromagnetic model by taking nonlinear magnetic field change as a boundary condition, solving the superconductor loss value of each representative turn in the excitation and demagnetization process, and obtaining the superconductor loss value of the whole coil through interpolation calculation; according to the method, the overall loss value of the large iron-based superconducting coil is calculated according to the loss value of a small number of iron-based superconducting strips by adopting an interpolation method, the calculation precision and calculation efficiency of the loss of the large coil can be remarkably improved, and a rapid reference is provided for subsequent design optimization of the large coil.
Owner:HEFEI INSTITUTE OF PHYSICAL SCIENCE CHINESE ACADEMY OF SCIENCES

A method for identifying control parameters of a doubly-fed wind turbine based on LSTM-IPSO

The application discloses a kind of based on LSTM-IPSO doubly-fed fan control parameter identification method, including the following steps: using RT-LAB semi-physical simulation platform obtains the hardware-in-the-loop experiment data of doubly-fed fan derived from real controller, and the isomorphic identification model of real controller of doubly-fed fan is built on Matlab / simulink platform;Increase input feature set dimension and remove irrelevant features, select the correlation higher characteristic value as the input feature set of the neural network model;Control parameter-input feature set is formed by input feature set and corresponding control parameter set;Using LSTM neural network, control parameter-input feature set is trained and predicted, and the predicted initial value and optimization range are obtained;Using IPSO algorithm as the secondary optimization method of accurate identification, the purpose of accurate optimization is achieved;Judge the reliability of identification model;The application solves the technical problem that traditional identification method is difficult to accurately identify the control parameter of doubly-fed fan electromagnetic model under low voltage ride through condition.
Owner:CHINA THREE GORGES UNIV

Permanent magnet synchronous motor temperature characteristic simulation method and system for motor simulator

The invention relates to the technical field of motor port characteristic simulation, in particular to a permanent magnet synchronous motor temperature characteristic simulation method and system for a motor simulator, and the method comprises the steps: adding a temperature model composed of a loss model, a thermal circuit model and a variable parameter model on the basis of a traditional mathematical model under a dq coordinate system of a permanent magnet synchronous motor; the simulation of the temperature characteristics of the permanent magnet synchronous motor is realized, the adopted temperature models are all realized in the form of analytical expressions or lookup tables, the calculation amount of the model forms is relatively small, and through the coupling of the motor electromagnetic model and the temperature models, not only can the temperature change in the operation process of the motor be reflected, but also the influence of the temperature on the motor parameters can be reflected. A closed-loop process is formed, so that the simulation result of the motor simulator is closer to that of a real motor, and the simulation precision is improved.
Owner:XI AN JIAOTONG UNIV +1

Partial discharge quantitative calibration method based on modal decomposition and frequency weighting

The invention relates to the field of partial discharge quantitative calibration and electromagnetic simulation analysis, in particular to a partial discharge quantitative calibration method based on modal decomposition and frequency weighting. The method comprises the following steps: acquiring a structure parameter, a defect excitation parameter, an ultrahigh frequency sensor position parameter and a sensitive direction parameter, establishing an electromagnetic model, and performing finite difference time domain simulation to obtain a frequency domain response spectrum; obtaining each modal frequency domain component set through modal expansion and waveguide eigenmode orthogonal projection; performing inverse transformation and wavelet transformation on each modal frequency domain component set to obtain time-frequency energy distribution, and extracting total energy, energy weighted arrival time, dispersion degree and frequency energy spectrum to generate a modal characteristic quantity set; and normalizing the modal characteristic quantity set to obtain a modal quality factor weight and generate a frequency correlation weight function, synthesizing an equivalent calibration transfer function, inverting a discharge current in combination with an actually measured voltage frequency spectrum, and integrating to obtain an apparent discharge quantity. According to the invention, the quantification reliability of apparent discharge capacity can be effectively improved.
Owner:STATE GRID JIANGSU ELECTRIC POWER CO LTD RESEARCH INSTITUTE +1