3297 results about "Electromagnetics fields" patented technology

The invention discloses a power transmission line connection fitting fault detection method based on acoustics and electromagnetic induction, and belongs to the technical field of intelligent inspection and nondestructive detection of power transmission lines. A multi-mode sensor is carried by an unmanned aerial vehicle, ultrasonic wave, vibration, images and power frequency electromagnetic field data are synchronously collected, and a multi-dimensional original data set is constructed. Signal quality is improved by adopting wavelet noise reduction, beam forming and sound image fusion technologies, and flight vibration and electromagnetic interference are effectively suppressed by combining an adaptive filtering algorithm and a physical shielding structure. And acoustic, image and electromagnetic characteristics are extracted and normalized and fused, a dynamic threshold reference library is established, and intelligent grading discrimination of abnormity, defects and faults is realized through multi-stage early warning logic. A detection result automatically generates a report and is mapped to a three-dimensional line model, and operation and maintenance system linkage is supported. According to the method, synchronous identification of surface and internal defects is realized, the anti-interference capability is high, the detection accuracy is high, the inspection efficiency and safety are remarkably improved, and the method is suitable for intelligent operation and maintenance of the high-voltage transmission line.

The invention relates to the technical field of aircraft structure detection, and discloses an aircraft structure crack intelligent identification method based on deep learning. The method comprises the following steps: acquiring original vibration response signals and electromagnetic field distribution data on the surface and inside of an aircraft structure in parallel through a multi-source sensor network; synchronously processing the data by using a multi-scale convolutional neural network, and extracting time-frequency domain abnormal fluctuation features and space magnetic field distortion features; constructing a cross-modal correlation model, analyzing a topological dependency relationship of the two types of features through a graph attention mechanism, and generating a fused damage sensitive feature vector; inputting the vector into a pre-trained deep belief network to obtain a probability distribution mapping relation for different crack types; and according to the mapping relation, carrying out adaptive weighted fusion on original multi-sensor data, inhibiting environmental noise and structural background interference, and separating and reconstructing an accurate three-dimensional morphology map of the target crack. According to the method, multi-source data information can be effectively fused to improve the accuracy of aircraft structure crack identification.

The invention relates to power transmission line unmanned aerial vehicle inspection, and discloses a power transmission line unmanned aerial vehicle inspection path dynamic planning system, which comprises a quantum high-precision positioning unit, an environment perception and electromagnetic field modeling unit, a dynamic path planning unit, an unmanned aerial vehicle flight control unit and a ground station task management unit. The quantum positioning unit fuses quantum inertial navigation, GNSS and quantum magnetometer data to improve the positioning precision under strong interference; the environment sensing unit obtains a three-dimensional environment and electromagnetic field distribution of the power transmission line; the path planning unit dynamically optimizes an inspection path based on positioning and environment information; the flight control unit performs accurate execution; and ground station management tasks and data analysis. The anti-interference positioning precision of the unmanned aerial vehicle is remarkably improved, accurate path planning and electromagnetic field avoidance are realized, the inspection risk is effectively reduced, and the efficiency, the safety and the adaptability are improved.

The invention provides an electromagnetic field prediction method and device and electronic equipment, and relates to the technical field of electromagnetic field solving. The method comprises the following steps: acquiring historical electromagnetic original data in a field-line coupling scene, preprocessing the historical electromagnetic original data, inputting the preprocessed historical electromagnetic original data into an LSTM-PINN model, and outputting a physical field quantity mapping result; wherein the physical field quantity comprises an electric field component and a magnetic field component; setting a weighted loss function, and performing optimization training on the LSTM-PINN model based on a physical field quantity mapping result and an error of a real physical field quantity corresponding to historical electromagnetic original data to obtain a trained electromagnetic field prediction model; wherein the weighted loss function comprises a data loss function, a physical residual loss function, an initial condition loss function and a boundary condition loss function; and inputting real-time electromagnetic original data into the trained electromagnetic field prediction model to obtain a spatio-temporal distribution electromagnetic field prediction result. The method can effectively extract the spatial distribution features and the time sequence features at the same time, and is suitable for a complex field-line coupling problem.

The invention discloses a cable sheath ring current fault positioning in-loop simulation method and system based on LABVIEW. The method comprises the following steps: collecting ring current data of cable sheath monitoring points in real time under the control of LABVIEW, and carrying out digital display and graphical display; decomposing circulation data to obtain a wavelet coefficient and calculating features, and inputting a classification model to obtain a fault type when the features are abnormal; calculating a compensation coefficient considering the influence of the electromagnetic field, and calculating the position of a fault point in combination with a double-end traveling wave method; the operation model switches a typical working condition simulation mode, prediction of a Bayesian reasoning correction model is carried out, and the full-life-cycle operation state of the cable is simulated; and performing fault early warning through the LSTM model and risk assessment. The method can effectively improve the cable operation and maintenance efficiency and reliability, and is widely applied to cable fault detection and guarantee of safe and stable operation of a power system.

The invention provides an intelligent eddy current nondestructive testing method and system based on a flexible GMR sensor array, and relates to the technical field of nondestructive testing. According to the invention, a GMR sensor array and a micro excitation coil array are integrated on a flexible substrate, and synchronous acquisition under multi-frequency and multi-phase excitation is realized by establishing a probe-workpiece unified space coordinate system and a time synchronization reference; performing temperature drift compensation, attitude correction and gap normalization processing on the original response tensor to generate a corrected response tensor; the intelligent inversion model based on the prior constraint of the electromagnetic field jointly identifies the conductivity, the thickness and the crack parameters, and outputs a defect parameter map and a confidence map; and a detection report containing the position, the size, the depth and the confidence coefficient is generated through spatial clustering and connectivity analysis, so that high-sensitivity and high-reliability nondestructive detection under a complex curved surface structure is realized.

The invention provides a self-adaptive efficient simulation method and system for electric propulsion plasma oscillation, and relates to the technical field of electric propulsion plasma oscillation simulation. According to the method, a high-precision electric propulsion plasma numerical simulation model is adopted to ensure the precision of a simulation result; according to the method, the calculation tasks of the simulation model are decomposed through various adjustment parameters, that is, all the calculation tasks are completed in a parallel calculation mode, and therefore the simulation efficiency can be effectively improved. Moreover, when the simulation model is subjected to simulation solving, the electromagnetic field solving model is solved by adopting a multi-grid method, and the simulation calculation efficiency can be further improved based on the solving mode. Besides, the target neural network model is utilized to process the simulation result so as to update all the adjustment parameters in the process, so that a plurality of adjustment parameters used in the simulation process are continuously and adaptively optimized, and the technical effect of considering the simulation efficiency and precision of the electric propulsion plasma oscillation simulation model is achieved.

The invention discloses a transformer substation positioning and navigation method and system integrating positioning and visual auxiliary positioning. The method comprises the following steps: establishing a background electromagnetic field distribution baseline graph associated with a three-dimensional reference map; electromagnetic field data of the transformer substation in an emergency response mode is collected through the unmanned aerial vehicle, and the abnormal field intensity of a space electromagnetic field and a fault source pointing vector pointing to a fault source are calculated; constructing a risk adaptive elliptical forbidden zone; calculating a passage cost index Cto of the unmanned aerial vehicle passing through each three-dimensional grid in the three-dimensional reference map by using the fault source pointing vector and the risk adaptive elliptical forbidden zone; and searching a path which is from the current position of the unmanned aerial vehicle to a preset target point, bypasses the risk adaptive elliptical forbidden zone, faces the fault source and has the lowest total passing cost index Cto by adopting a preset path search algorithm. According to the method, the risk self-adaptive elliptical forbidden zone is constructed and is used as the three-dimensional grid forbidden assignment processing, so that the dynamic global path avoidance of the sudden dangerous zone is realized.

The invention relates to the field of electric power material warehouse management and control, in particular to an electric power material digital intelligent professional warehouse management and control method, which comprises the following steps: acquiring electromagnetic spectrum data, identifying a central frequency point energy distribution diagram and an electromagnetic interference intensity level, constructing a three-dimensional electromagnetic field intensity distribution model of a professional warehouse, and dynamically adjusting the working mode of an RFID reader-writer; the method comprises the following steps: deploying a multi-modal check node in a storage area of a professional warehouse, and generating a composite check result through an infrared contour matching method and a UWB coordinate verification method when the confidence coefficient of electric power material data read by an RFID reader-writer is lower than a preset confidence coefficient threshold value; updating an electric power material inventory database according to a composite verification result, and performing electric power material inventory state analysis in real time through an edge computing node; the problems that inventory data distortion and material positioning deviation are caused by reduction of the accuracy rate of RFID in a strong electromagnetic environment, and inventory accuracy management of an electric power material warehouse is seriously restricted are solved.

The invention belongs to the technical field of geophysical monitoring, and relates to an electromagnetic interference detection method for earthquake monitoring, which comprises the following steps: deploying a multi-dimensional electromagnetic field sensing unit and an earthquake signal acquisition unit and realizing high-precision synchronization; synchronously acquiring multi-dimensional electromagnetic field and seismic physical signal data; performing multi-feature and noise feature extraction on the two; inputting the features into a pre-trained machine learning / deep learning model for identification, and outputting information such as interference type, intensity and azimuth angle; and carrying out influence evaluation and quality marking on the seismic data according to the output, and selectively inhibiting or compensating. Through the above scheme, multi-dimensional perception and characterization, high-precision synchronization and correlation analysis, intelligent identification and spatial positioning are realized, and the reliability and accuracy of earthquake monitoring data are significantly improved.

The invention provides a fractured rock mass surrounding rock grouting quality evaluation method, and relates to the technical field of geotechnical engineering.The method comprises the following steps that permeability test data and acoustic velocity test data of fracture connectivity and mechanical states of a target surrounding rock area are obtained before grouting, and a characterization parameter data set of fractures before grouting is formed; synchronously acquiring three-dimensional point cloud data to calculate the volume of a fracture cavity; in the grouting process, electromagnetic field intensity data is collected to calculate the grouting filling rate, resistivity time sequence data is collected to calculate the cementation uniformity index, strain time sequence data is collected to calculate the strain gradient, and a grouting integrity index is formed through multi-feature fusion; after grouting, permeability and sound wave velocity data are obtained again, and the fracture characterization performance improvement rate is calculated; acquiring penetration test data to calculate a stone body strength parameter; and performing multivariate fusion on the grouting integrity index, the fracture characterization performance improvement rate and the stone body strength parameter to calculate a comprehensive quality score, and comparing the comprehensive quality score with a preset threshold value to perform grading evaluation.

The invention relates to the technical field of transformer simulation, in particular to a simulation system and method for a temperature rise field of a dry-type transformer. The method comprises the following steps: acquiring geometric parameters of an iron core lamination of the dry-type transformer to be simulated, spatial arrangement information of a winding and a positioning relation of an insulating component to form structural design data; the method comprises the following steps: constructing three-dimensional geometric modeling data based on structural design data, importing the three-dimensional geometric modeling data into a finite element electromagnetic simulation platform, setting a power-on condition of an excitation winding, and applying rated current or voltage, so as to obtain local magnetic flux density distribution data at each iron core lamination position in a whole operation period. According to the method, on the basis of three-dimensional structure data, three physical processes of an electromagnetic field, a thermal field and a fluid field are fused, a high-precision local heat source model and a dynamic temperature rise prediction model are constructed, and geometry-material-boundary all-parameter modeling is achieved from the whole structure of an iron core lamination, a winding and an insulation assembly.

The invention belongs to the technical field of medical imaging and digital twinning, and discloses a thoracic cavity whole organ system level lung four-dimensional EIT detection digital motif and a library building method, and the method comprises the following steps: S1) segmenting multiple organs such as double lungs, heart, sternum, rib and thoracic vertebra central axis skeleton, main bronchus and esophagus based on an individual CT image, and building a three-dimensional geometric model integrated with an EIT electrode array; s2) simulating breathing dynamic deformation by using a solid mechanical model; s3) establishing a coupling relationship between deformation and conductivity, and generating dynamic three-dimensional conductivity distribution; s4) solving an electromagnetic field positive problem, and generating a virtual EIT voltage database synchronous with respiration; the invention also covers pathological model integration and data enhancement strategies. According to the method, a high-fidelity, large-scale and diversified EIT virtual data set can be generated, core data support is provided for training and verifying an AI intelligent reconstruction algorithm, and a model foundation is laid for developing a lung function dynamic digital twinning system.

The invention discloses a transformer substation intelligent patrol recognition algorithm optimization method based on multi-modal fusion, and belongs to the technical field of transformer substation patrol, and the method comprises the following steps: synchronously obtaining a visible light image, an infrared thermal imaging spectrum, an ultrasonic partial discharge signal and environmental parameters, and building a four-dimensional space-time calibration matrix; a dual-channel attention mechanism is adopted to realize multi-source data fusion, a spatial alignment channel and a feature enhancement channel are included, the spatial alignment channel realizes pixel-level registration of visible light and infrared images through affine transformation, and the feature enhancement channel utilizes a graph neural network to construct topological correlation mapping of acoustic, thermal and optical features; constructing a three-stage training architecture containing noise injection; and adding an adversarial generative network in a preprocessing layer to simulate rain fog and electromagnetic interference environments. According to the method, the identification threshold is updated online by deploying a sliding time window mechanism in an output layer, and the problems of poor feature extraction robustness and high false alarm rate of a traditional algorithm in complex environments such as strong electromagnetic fields and rain and fog are solved.

The invention discloses a method for effectively studying and judging false alarm of a fire alarm system in a transformation power station in a multi-dimensional mode, and the method comprises the steps: collecting and fusing multi-channel sensor data, such as smoke concentration, temperature, humidity, electromagnetic field intensity, grounding state and the like, and constructing a scenarized data set in combination with an environment label and an operation and maintenance log; through multi-level feature processing such as normalization, wavelet denoising and dimension reduction, the data quality and discriminability are improved; according to the method, the space-time diagram neural network is used for achieving multi-period environment subarea and typical signal mode division, multi-period fusion confidence judgment is conducted on alarm signals based on the fuzzy set theory and Bayesian reasoning, dynamic judgment of false alarms and real alarms is achieved, and the accuracy and robustness of alarm judgment in the complex environment are effectively improved.

The invention discloses a broadband wave-absorbing material based on an MAX-phase metasurface structure and an impedance matching optimization method of the broadband wave-absorbing material. The wave-absorbing material comprises an MAX-phase ceramic substrate and periodic metasurface structures which are arranged on the surface of the MAX-phase ceramic substrate in an array mode and composed of conductive resonance units. The resonance units are isolated through gaps, an equivalent R1L1C1 series resonance circuit is formed in an electromagnetic field, and a base body is equivalent to a parallel resistor R2. By establishing an equivalent circuit model and optimizing parameters R1, L1, C1 and R2, impedance matching of the wave-absorbing material in a target frequency band can be regulated and controlled, so that the wave-absorbing material at least has an absorption peak of which the reflection loss is less than-10 dB. According to the optimization method, electromagnetic simulation and circuit simulation are combined, optimized circuit parameters are reversely mapped into structure geometric parameters, material preparation is guided, and accurate design and broadband absorption of the wave absorbing performance are achieved.

The invention relates to the technical field of electromagnetic coils, in particular to a laminated special-shaped plane spiral coil winding. The laminated special-shaped planar spiral coil winding is composed of at least two coil layers, and each coil layer is composed of a single special-shaped planar spiral coil. The inner ring part of the special-shaped plane spiral coil is a concentric plane spiral coil, and the outer ring part of the special-shaped plane spiral coil is a tooth-shaped spiral coil extending along the outer periphery of the concentric plane spiral coil; all phases of the coil winding are different in layer, the electrified magnetic field center of each coil layer deviates from the geometric center, and the projection of the magnetic field center of each phase in the plane of the coil winding is in central symmetry distribution. The invention innovatively provides a laminated special-shaped planar spiral coil winding, and provides a squirrel-cage equivalent rotor on the basis of the laminated special-shaped planar spiral coil winding, so as to provide competitive choices for reducing copper loss and improving heat dissipation, magnetic conductivity, structural strength and economic cost of an axial flux motor winding.

The invention discloses a non-uniform and conformal grid-oriented electromagnetic particle adaptive simulation method and system, and relates to the technical field of electromagnetic particle simulation. The method comprises the following steps: performing non-uniform right-angle mesh generation based on a charged particle average free path, and identifying conformal mesh units; carrying out initialization by adopting macro particles; executing electromagnetic field propulsion, field interpolation, particle propulsion, charge current backfilling and collision simulation in each time step; and accelerated calculation is realized through a CPU and GPU hybrid parallel architecture. Through the method, the numerical simulation precision can be improved, the adaptability of complex geometry is enhanced, the coupling stability of the electromagnetic field and the particles is ensured, the information interaction between the field and the particles is improved, and the large-scale calculation efficiency is improved.

The invention relates to a track planning method and system for a bridge crane, and the method comprises the steps: collecting motion signals of a main beam and a trolley through an electromagnetic field intensity detection sensor array, carrying out the denoising of the motion signals, extracting features, decomposing the features into component signal groups, building the incidence relation between the component signal groups and the motion state of a joint, and achieving the high-precision dynamic positioning. A time sequence model is constructed based on position data to analyze displacement and speed characteristics, a multi-dimensional constraint condition set including speed limitation and position boundaries is generated, a final trajectory scheme is output through iterative adjustment of an optimization calculation framework, a dynamic feedback mechanism is adopted, electromagnetic field intensity signals and planning data are compared in real time, and the optimal position is obtained. And when the deviation threshold is exceeded, readjusting the parameters, and generating a coordinated motion instruction to drive the crane to operate. Accurate positioning is achieved based on electromagnetic field intensity detection, the problems of accumulative errors and environmental interference of a traditional method are effectively solved, and the stability, accuracy and self-adaptive capacity of crane movement are remarkably improved.

The invention discloses an electromagnetic field simulation grid adaptive generation method based on a neural network. The method comprises the following steps: performing mesh generation on a semiconductor device simulation model to obtain original generation data, and constructing node features; an undirected graph is constructed, graph nodes of the undirected graph adopt node features of grid points, and connecting edges adopt Euclidean distances between the grid points and adjacent grid points; inputting the undirected graph into a double-branch neural network, and outputting a predicted node position; and correcting each node of the original subdivision data by using the predicted node position obtained by the double-branch neural network to form new subdivision data for electromagnetic field simulation. According to the method, physical field information can be fused to efficiently adjust the node density, and the geometric boundary and topological structure characteristics of the device can be strictly kept.

The invention provides a rapid wire falling control method for an overhead transmission cable inspection robot, and relates to the technical field of intelligent control, and the method comprises the steps: obtaining electromagnetic field intensity data monitored by an airborne electromagnetic sensor in real time according to a corrected wire falling path; according to the electromagnetic field intensity data, counteracting pose offset of the unmanned aerial vehicle and the working platform caused by electromagnetic interference in real time to obtain a control signal after the pose offset is counteracted; and driving the unmanned aerial vehicle and the working platform to execute a wire falling control action according to the corrected wire falling path and the control signal after the offset of the pose offset until the working platform realizes stable hovering positioning at a specified position of the target ground wire. According to the invention, automation and intelligence of power transmission cable inspection are improved.

The invention provides a high-precision laser additive manufacturing method and device based on metal powder melting, and relates to the technical field of metal additive manufacturing, and the high-precision laser additive manufacturing device comprises a multi-element powder supply and electrification unit which is used for carrying out independent metering supply and airflow dispersion mixing on various metal powder in an inert atmosphere environment and enabling powder particles to obtain controllable charges; the electromagnetic field cooperative control unit is used for actively regulating and controlling the falling speed and the transverse track of the powder particles through the cooperative effect of a longitudinal magnetic field and a transverse electric field when the powder particles are in a charged state; the invention provides a metal powder forming technology path based on particle size active conveying and spatial positioning, and active conveying and accurate positioning of the metal powder particles in the flying process are realized by performing electrified regulation and control on single or small-scale metal powder particles and utilizing the action of an electromagnetic field. Therefore, layer-by-layer stacking forming is completed under the condition of not depending on the whole powder laying layer.

The invention discloses an automobile part multi-source fusion tracing method and system based on a distributed block chain. Firstly, a block chain network and a tracing platform are constructed; a microscopic visual feature image of the surface of the automobile part is collected, the texture type is judged, features are extracted, electromagnetic field intensity distribution features are extracted in combination with an RFID tag, and electromagnetic fingerprints are recognized through a neural network; secondly, multi-source feature data and production and transportation information are bound with unique identifiers and then stored in a distributed block chain network, and a five-layer Merkel tree storage structure is adopted to ensure that the data cannot be tampered; and finally, constructing a tracing query module of a three-layer architecture, and automatically managing data writing and query through an intelligent contract. According to the invention, through combination of multi-feature fusion and the block chain technology, the problems of information island and weak traceability of a traditional traceability system are solved, credible traceability and authenticity identification of automobile parts in the whole life cycle are realized, and the supply chain data security and query efficiency are improved.

The invention provides an electromagnetic thermal multi-physical field simulation method based on an FDTD / FVTD algorithm, and belongs to the technical field of electromagnetic simulation. Performing time domain finite difference discretization on the established spatial discrete model by adopting a Yee cellular structure, and calculating electromagnetic field distribution according to a Maxwell rotation equation; constructing an adaptive steady-state judgment criterion based on the instantaneous total energy change rate, and updating electromagnetic field distribution of the spatial discrete model by adopting an FDTD explicit method; calculating the electromagnetic loss power density of the spatial discrete model, and transmitting the electromagnetic loss power density into a thermal field for calculation; based on an FVTD method, thermal field distribution of the discrete model is calculated through an explicit or implicit format, and thermal field distribution information is obtained. The FDTD method is based on explicit time domain iteration, transient behaviors such as electromagnetic wave propagation and scattering can be visually captured, and the FDTD method has broadband response capability and complex medium adaptability and is especially suitable for the high-frequency electromagnetic problem. The FVTD method strictly ensures energy conservation, directly treats boundary heat flux and is suitable for non-uniform materials and complex heat transfer boundary conditions.

The invention belongs to the technical field of liquid metal coating and infiltration in grinding machining, and particularly relates to a temperature-control ultrasonic composite liquid gallium auxiliary grinding device and method for a micro engine blade, and the device comprises a fluid conveying module, a temperature adjusting module, a machining module, an ultrasonic vibration module and an electromagnetic field generator. Temperature control of liquid gallium is achieved by arranging a microwave cavity and a cooling system, stable supply is guaranteed through inert gas and a liquid gallium conveying pipeline, and uniform coating and ultrasonic vibration infiltration on the surface of the blade of the micro engine are achieved by combining an ultrasonic transduction assembly and a spraying nozzle. The electromagnetic field generator further enhances the adhesion and lubrication effects of the liquid gallium on the grinding wheel and the blades. The defects of insufficient grinding temperature control and lubrication of a traditional grinding wheel are overcome, the grinding temperature rise and the friction coefficient are effectively reduced, thermal damage and surface deformation are avoided, and the machining precision and the surface quality of complex curved surfaces and tenon tooth parts are improved.

The invention discloses a multi-scene wireless network rapid deployment method based on an electromagnetic field digital twinning technology, and relates to the technical field of computer application, and the method comprises the following steps: S1, constructing a three-dimensional digital twinning model of a corresponding scene, and integrating a building structure, equipment layout and material attribute data, and establishing a scene special material database containing metal equipment, a concrete wall body and an electromagnetic shielding layer. According to the multi-scene wireless network rapid deployment method provided by the invention, the three-dimensional digital twin model is constructed, and the building structure, the equipment layout and the material attribute data are integrated, so that the precise simulation of the environment is realized, the wireless network deployment accuracy is improved, the deployment scheme can better adapt to the dynamic change of the environment, and the deployment efficiency is improved. The improved O-FDTD algorithm is adopted to simulate electromagnetic field propagation in a building in real time, and the problem that the calculation efficiency is low when a traditional FDTD algorithm processes the metal edge effect and a moving object is effectively solved.

The invention provides a hydraulic fracturing fracture net distribution form near-field monitoring method, which comprises the following steps of: arranging a plurality of roof monitoring holes in roadways on two sides of an underground coal mine working surface, installing electromagnetic signal sensors in each roof monitoring hole and on anchor rods of roadway stoping sides, and constructing a full-space monitoring network covering a hydraulic fracturing layer; a data interpretation processing module of the electromagnetic signal time-shifting imaging analysis system comprises a multi-field coupling mathematical model for analyzing and deducing real-time imaging of electromagnetic signals; in the hydraulic fracturing process, an electromagnetic signal sensor is used for monitoring a current field, an electromagnetic field and an ion diffusion field in the rock mass fracture development and expansion process, a monitoring result is substituted into an electromagnetic signal time-shifting imaging analysis system for calculation and feature value extraction, and the fracture net distribution form is deduced through the feature value. According to the invention, the expansion path of the fracturing fluid in the rock stratum can be monitored in real time, the three-dimensional distribution form of the hydraulic fracturing fracture network can be inverted, and a new technical support is provided for the inspection of the hydraulic fracturing pressure relief effect of the underground coal mine.

The invention discloses a cable temperature simulation model construction method and system based on multi-field coupling, and relates to the technical field of multi-physical field coupling simulation and tunnel cables, and the method comprises the steps: constructing a three-dimensional geometric model based on actual cable structure parameters and cable tunnel three-dimensional scanning data; physical field parameters are set for all layers of materials of the cable and peripheral media of the tunnel, boundary heat dissipation conditions are defined, two-dimensional grid division is conducted on the model according to the axial symmetry characteristic of the cross section of the cable, processing frequency load current excitation is applied, electromagnetic field distribution is solved, and a three-dimensional steady-state temperature field control equation is constructed; and solving three-dimensional temperature distribution of the cable and tunnel environment, establishing a bidirectional coupling relationship between an electromagnetic field and a temperature field, and iteratively updating Joule loss power and temperature field distribution by dynamically adjusting conductor conductivity until a convergence condition is met. According to the invention, real-time monitoring and early warning of the temperature along the cable are realized, and detection and response at the initial stage of a fault are ensured, so that the operation safety and reliability of a power system are improved.

The invention discloses a high boundary sensitivity three-dimensional inversion method based on an electromagnetic gradient constraint matrix, and belongs to the technical field of electromagnetic signal inversion, and the method comprises the steps: constructing an initial inversion model and a target function, and introducing a model roughness item based on electromagnetic gradient constraint into the target function; calculating the electromagnetic gradient anomaly response at each measuring point under each measuring frequency, obtaining an electromagnetic gradient anomaly response vector of each measuring point, performing normalization processing, combining into a matrix, obtaining an overall normalized observation gradient anomaly matrix, and constructing an electromagnetic gradient constraint matrix in a data space; converting the electromagnetic gradient constraint matrix in the data space into a model space through a frequency-depth weighted mapping matrix; and solving the target function by adopting an iterative optimization algorithm until the model converges. According to the method, the gradient constraint matrix based on the electromagnetic field is introduced, the dynamic adjustment of the change amplitude weight of each grid unit in the roughness item of the model is realized, and the target boundary identification precision is improved.

The invention relates to the field of vacuum circuit breakers, in particular to a vacuum circuit breaker opening and closing dynamic characteristic calculation method, device and equipment and a medium. Establishing a three-dimensional geometric model of the pole-mounted vacuum circuit breaker arc extinguish chamber and the moving and static contacts; setting material attributes for each part in the three-dimensional geometric model; constructing a multi-physics field coupling system; the area where the moving contact is located is divided into movable grids, and the grid density of the moving contact and the grid density of the static contact dynamically change along with time; and performing multi-field coupling transient solution according to the three-dimensional geometric model, the multi-physical field coupling system and the movable grid to obtain the dynamic characteristics of the vacuum circuit breaker. The electromagnetic field, the thermal field, the fluid field, the structure field and the circuit are subjected to full coupling analysis, multi-physical field strong coupling dynamic simulation of the whole opening and closing process is achieved, and the dynamic characteristics of the whole opening and closing process can be accurately calculated.