3016 results about "Electric field" patented technology

The invention discloses an intelligent cable fault diagnosis and positioning method and system, and relates to the technical field of intelligent operation and maintenance of a power system. The method is used for accurately identifying and positioning high-resistance faults and external damage. According to the method, electric field, current, temperature and vibration signals are synchronously collected, a multi-source fusion enhanced signal flow is constructed, and multi-physical field features are extracted; based on a coupling mechanism of an electromagnetic-thermal field and a mechanical-electric field, generating a fault type label and a space coordinate; executing targeted impedance correction for different fault types, establishing a dynamic topology network, and inputting a time-space diagram neural network to output a preliminary positioning result; and multi-source verification is carried out by further fusing salinity dielectric, a harmonic thermal field, a vibration electric field and stress topological information, a high-confidence-coefficient fault positioning result is finally output, a closed-loop diagnosis mechanism is formed, and the fault recognition accuracy and the system adaptability under complex working conditions 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 belongs to the technical field of geophysical exploration in an extremely complex tunnel environment, and provides an air-ground and hole-tunnel multi-angle combined tunnel unfavorable geology advanced detection system and method.A first main control unit is used for establishing a unified time reference and controlling an air-ground capacitive induced polarization detection unit to collect air-ground electric field data under the unified time reference; the second main control unit is used for controlling the hole-tunnel induced electric field and natural electric field combined detection unit to collect underground induced polarization response signals and continuous natural electric field signals and controlling the tunnel seismic electric field detection unit to collect seismic electric field signals and seismic wave signals; and the second main control unit is used for receiving the air-ground electric field data sent by the first main control unit, uniformly integrating the air-ground electric field data with an underground induced polarization response signal, a continuous natural electric field signal, a seismic electric field signal and a seismic wave signal which are acquired by the second main control unit to obtain a multi-field data set, and performing interpretation and inversion to obtain a potential unfavorable geologic body identification result. And the disaster source detection precision and efficiency in the extremely complex tunnel environment are obviously 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 a non-contact electric power parameter measurement method, system and device, and a storage medium. The method comprises the steps of obtaining a first output voltage signal and a second output voltage signal generated by induction of a space electric field around a to-be-measured wire; establishing an equation set of a to-be-measured voltage phasor based on the first output voltage signal and the second output voltage signal, and solving the equation set of the to-be-measured voltage phasor to obtain a parameter of the to-be-measured voltage; acquiring a magnetic field measurement signal generated by a space magnetic field around the to-be-measured wire; and establishing an equation set of the current to be measured according to the magnetic field measurement signal, and solving the equation set of the current to be measured to obtain parameters of the current to be measured, thereby effectively solving the problem that the gain and the phase shift are unknown after the probe is connected.

The invention belongs to the technical field of geological engineering monitoring and multi-physics field intelligent sensing, and discloses a separation grouting slurry migration monitoring method and system, and the method comprises the steps: constructing an acoustics-optics-electricity-electromagnetism multi-physics field coupling monitoring system; a grouting hole and a monitoring drilling hole array are arranged in a target stratum, a distributed optical fiber sensor, a drilling hole ultrasonic imager, a resistivity measuring device and a transient electromagnetic detection device are installed, and a three-dimensional monitoring network is formed; synchronously acquiring sound field, light field, electric field and magnetic field data; four-field monitoring data and overlying strata multi-parameter observation data are fused, a coal seam mining three-dimensional overlying strata separation model is constructed, and a slurry diffusion three-dimensional visualization model is generated through numerical simulation; and based on the four-field monitoring response difference of the separation space before and after grouting, in combination with a monitoring frequency domain correction model of multiple indexes of grout diffusion, the diffusion range, compactness and filling effect of the grouting grout are evaluated, and abnormal early warning is triggered.

The invention discloses a gas meter power supply abnormity monitoring system and method based on a signal acquisition technology, and relates to the technical field of gas meter power supplies, the system comprises a multi-dimensional sensing module, a dynamic adaptive module, a multi-dimensional fusion analysis module, an intelligent judgment module and a verification execution module; according to the invention, the multi-dimensional fusion analysis module accurately calculates key parameters such as a power supply ripple coefficient and load transient response time in a corresponding mode, the electromagnetic interference intensity is calculated through professional algorithms such as discrete Fourier transform in combination with an environment electric field and a magnetic field sequence, a threshold value is dynamically adjusted based on a working mode, and a comprehensive score is calculated through multi-parameter deviation weighted fusion. The power supply state is deeply and comprehensively evaluated; the intelligent judgment module scientifically divides anomaly levels according to comprehensive scores, quantifies and distinguishes real anomaly and environmental interference by means of an environmental interference contribution degree formula, solves the problem that traditional monitoring cannot accurately recognize power anomaly under complex working conditions, and improves anomaly judgment accuracy.

The invention relates to the technical field of oil field reservoir research, in particular to a fracturing fracture imaging physical simulation method and system combined with non-uniform contact electrodes, and the method comprises the steps: carrying out the resistance modal detection at the current time step through a low-frequency excitation signal in the fracture propagation simulation process, and obtaining a corresponding electric signal; obtaining a conductive fluid distribution result of the rock core fracturing test piece at the current time step by using the conductive fluid distribution inversion model; and fitting and comparing the electric field distribution result of the current time step with the conductive fluid distribution result of the current time step, and outputting the fracture parameters and the conductive fluid distribution result of the rock core fracturing test piece at the current time step based on the fitting and comparison result. According to the method, the electrical property change caused by the natural fracture and the fluid contained in the natural fracture is directly sensed in situ, the electrical signal is acquired, the response delay is reduced, the conductive fluid distribution inversion model is constructed by combining prior knowledge and deep learning, and the precision and reliability of conductive fluid distribution inversion are effectively improved.

The invention discloses a dynamic electromagnetic shielding method for a complex electromagnetic environment and a shielding device thereof, and the method comprises the steps: obtaining real-time voltage data in the complex electromagnetic environment, carrying out the voltage feature analysis, outputting a feature vector of a real-time voltage signal, and analyzing the type of an interference source of a current electric field according to the feature vector, performing interference trend time sequence prediction processing on the feature vector through a pre-trained LSTM model according to the interference source type to obtain a time domain voltage value and a phase deviation value, and performing composite loss coefficient calculation on the time domain voltage value and the phase deviation value to obtain a composite loss coefficient; and performing reverse offset signal synthesis processing on the voltage interference signal according to the calculated composite loss coefficient, performing coil dynamic activation processing on a preset multi-coil array according to the synthesized reverse offset signal, generating a directional offset magnetic field corresponding to the real-time electromagnetic interference, and performing electromagnetic offset shielding on the current electromagnetic interference. According to the invention, transient interference can be responded in time, and the electromagnetic shielding effectiveness can be improved.

The invention relates to the technical field of array antennas, in particular to a sparse linear array beam forming method and system with unit rotation and mutual coupling considered. Array elements are obtained, Euler angle derivation is carried out on rotation of the array elements around the z axis, and a radiation electric field after rotation is obtained; setting a beam forming target according to the electric field of the radiation field; according to a beam forming target, optimizing the position, the rotation angle and the excitation phase of an array element by adopting a random optimization algorithm, and generating an initial beam scheme; an active directional diagram is extracted from the initial beam scheme according to full-wave simulation, the active directional diagram is combined with a CAL-SAPSO algorithm to optimize the array element position, the rotation angle and the excitation phase, and a final array element directional diagram is generated; according to the invention, by introducing array element rotation and considering a mutual coupling effect, efficient beamforming of the sparse wiring array is realized, the radiation characteristic of the antenna array can be adjusted more finely, the peak side lobe level and the cross polarization level are effectively reduced, and the overall performance of the system is improved.

The invention discloses a grounding grid electric heating power multi-field coupling modeling method and system considering soil nonlinear breakdown, and belongs to the technical field of power system grounding grids. The method comprises the following steps: establishing a three-dimensional geometric model containing a soil domain and a grounding grid conductor; defining non-linear conductivity characteristics of the soil; setting multi-physical field parameters and corresponding boundary conditions of the three-dimensional geometric model; and establishing a multi-physical field coupling control equation set including an electric field equation, a heat conduction equation and a thermal stress equation, and solving by adopting a finite element method to obtain three-dimensional space distribution data of the grounding grid under lightning current impact. According to the invention, on the basis of fully considering the nonlinear breakdown characteristic of the soil, the accurate simulation of the electric heating power multi-physical field behavior of the grounding grid under the impact current effect is realized, and the accuracy of impact impedance, potential distribution and temperature rise prediction is obviously improved.

The invention discloses a macro-micro hybrid simulation method for electrical equipment insulation defect analysis, which comprises the following steps: S1, establishing a gas defect discharge process simulation model, and describing microscopic particle state change and electric field distribution in a gas discharge process through a particle transport equation and a Poisson equation; the method comprises the steps of S1, establishing an electromagnetic propagation process simulation model, and describing the propagation process of an electromagnetic signal generated by gas discharge through a Maxwell equation set, and S3, performing joint simulation on the model, taking equivalent current of gas discharge as an excitation source, simulating propagation of the electromagnetic signal in power equipment through a finite time domain difference method FDTD, and recording a signal value of a receiver. According to the macro-micro hybrid simulation method for analyzing the insulation defects of the power equipment, the insulation defects of the power equipment are accurately analyzed and monitored, important support is provided for state monitoring and maintenance of the power equipment, and digital transformation of the monitoring technology of the power equipment is promoted.

The invention provides a transformer intelligent monitoring method and system based on artificial intelligence. The method comprises the steps that multi-dimensional data in the operation process of a transformer are collected in real time; establishing a cross-dimensional correlation model by using multi-dimensional data based on an attention mechanism in combination with a graph neural network algorithm; performing fault trend analysis based on fusion data output by the cross-dimension correlation model, predicting a fault change trend in a period of time in the future, and generating a fault prediction result; an equipment digital mirror image is constructed by adopting a data twinning technology, a physical process of fault development is simulated through coupling simulation of a magnetic field, an electric field and a temperature field driven by real-time monitoring data, and virtual-real linkage early warning is carried out in combination with a fault prediction result; through deep fusion of an artificial intelligence technology and transformer partial discharge monitoring, accurate identification and development trend prediction of partial discharge faults are realized, accurate fault identification can still be carried out even under a small sample condition, and the safety and reliability of power equipment operation are significantly improved.

The application discloses a Ka dual-circular polarization antenna unit and a flat plate array antenna, which comprises, from top to bottom, a radiation patch layer, a slot coupling layer, a waveguide transmission layer and a feed network layer; a plurality of microstrip line structures are arranged on the radiation patch layer, the microstrip line structure comprises a first microstrip line and a second microstrip line, and the first microstrip line and the second microstrip line form a 90-degree phase difference of electric field orthogonal components; the slot coupling layer comprises a second substrate, the second substrate is provided with a source collapse groove corresponding to the microstrip line structure, and the slot coupling layer and the radiation patch layer are relatively displaced under the action of an external force; the microstrip line structure corresponding to the source collapse groove is switched between a left-handed circular polarization microstrip line and a right-handed circular polarization microstrip line through the relative displacement; and the source collapse groove and the first substrate form a linear polarization feed source. According to the application, each dual-circular polarization feed source is used to form dual-circular polarization, and a polarization partition plate of a feed source waveguide is not relied on, so that the thickness of the antenna structure is reduced.

The invention belongs to insulation of superconducting power equipment, and particularly relates to a breakdown voltage prediction method for a liquid nitrogen, insulation barrier and bubble composite system. Comprising the following steps: acquiring electric field distribution characteristic parameters of the resistance type superconducting current limiter through simulation, and designing an equivalent electrode structure capable of reproducing electric field characteristics in a liquid nitrogen environment; establishing a first breakdown voltage prediction model taking the insulation barrier position parameters and the electrode spacing as variables; calculating the surface heat flux of the superconducting strip in the quench fault state; and introducing a bubble influence factor for correction to obtain a second breakdown voltage prediction model. A complex actual insulation system prediction problem is converted into an equivalent model problem which can be verified in a laboratory. And an accurate basis is provided for the insulation design of the resistance-type superconducting current limiter.

A linear displacement sensor based on electric field self-coupling, comprising a moving scale base (1) and a fixed scale base (2). One or more paired electrode units are provided on the side surface of the moving scale base (1) facing the fixed scale base (2); each paired electrode unit comprises at least three sensing electrode groups spaced in the length direction of the moving scale base (1); each sensing electrode group comprises one excitation electrode (1-1) and one sensing electrode (1-2) spaced in the length direction of the moving scale base (1). A plurality of modulation unit groups arranged in the length direction of the fixed scale base (2) are provided on the side surface of the fixed scale base (2) facing the moving scale base (1); in the length direction of the fixed scale base (2), all the paired electrode units on the moving scale base (1) can respectively correspond to the same number of adjacent modulation unit groups on the fixed scale base (2); each modulation unit group comprises one modulation unit F(2-1) and one modulation unit G(2-2); the modulation unit F(2-1) can correspond to at least one sensing electrode group in the paired electrode units in the length direction of the fixed scale base (2).

The invention discloses an Archimedes spiral anode rotary scanning electroforming device, and belongs to the technical field of electroforming. The Archimedes spiral anode is made of platinum with the width of 50 micrometers and the purity of 99.999%, the Archimedes spiral anode is embedded in the center of a line anode carrying plate, and the polar coordinate equation is that during electroforming, a cathode carrying plate rotates along with a rotating shaft at the rotating speed of 0.1-20 r / s, and uniform coverage of a cathode global electric field is achieved; the device is provided with an adjustable gap of 0.5-4 mm between two electrodes, a liquid supply channel is formed in the center of a wire anode carrying disc, the carrying disc is parallel to a cathode carrying plate, and the distance between the carrying disc and the cathode carrying plate is adjustable. The spiral line anode structure can solve the problem that a traditional radial anode is uneven in electric field; through the flow-rotating speed synergistic effect, the rotating centrifugal force of the cathode can be counteracted, and the interelectrode ion concentration is kept stable; the continuous helical structure can also eliminate non-effective working time. According to the method, the edge effect and the bubble defect are effectively restrained, the deposition uniformity, the electroforming efficiency and the deposition layer performance are improved, and the method is suitable for high-precision electroforming manufacturing of the chip type disc-shaped cathode substrate.

The invention provides a cable fault arc temperature distribution calculation method based on multi-physics field coupling, and the method comprises the steps: building a cable fault arc simulation model; setting boundary conditions of multi-physics field coupling of an electric field equation, a magnetic field equation, a fluid heat transfer equation and a laminar flow equation for the cable fault arc simulation model; the arc temperature distribution is obtained by controlling the voltage and current parameters of the arc simulation loop, the distance between the copper core conductor and the grounding electrode and the air velocity. A cable fault arc simulation model is built, high risks of electric shock and explosion in laboratory tests are avoided, the loss cost of laboratory test equipment is reduced, the defect that only the peripheral temperature of the arc can be measured in the laboratory tests is overcome through a multi-physics field coupling equation, and global continuous arc temperature data are obtained. And a theoretical basis is provided for power system protection design, cable laying optimization, fire-fighting strategy formulation and cable fire risk assessment.

The invention discloses an efficient and parallel PIC / MCC rapid calculation method and system. According to the method, a PIC / MCC calculation process is divided into a charge distribution module, an electric field solution module, a particle propulsion module and a collision processing module, and parallel execution is carried out on a GPU through an independent kernel function. All simulation data are resident in a GPU video memory, and storage access is optimized by adopting a structured array and row main sequence layout. GPU atomic operation is introduced in charge distribution to ensure data consistency; selecting a parallel algorithm to accelerate Poisson equation solution according to dimensions in electric field solution; an electric field is obtained through interpolation in particle propulsion, and the particle motion state is updated; and adopting a Monte Carlo method to judge the collision type in parallel in the collision processing. Synchronous control among the modules is realized through a GPU event mechanism, and self-consistency of a physical process is ensured. According to the method, the bottleneck of traditional serial calculation is broken through, the speed-up ratio of more than 30 times is realized while the calculation precision is kept, and the efficiency and expandability of plasma numerical simulation are remarkably improved.

The invention discloses a natural electric field-electric field joint detection and inversion method based on GMM prior, and relates to the technical field of tunnel engineering geological detection, and the method comprises the steps: obtaining the resistivity and natural potential observed in a to-be-inverted region; an equivalent body source of a natural potential is parameterized into a body source vector on a grid unit, weighted L1 sparse regular constraint is introduced into the body source vector, a GMM prior model is used as underground electrical structure prior shared across physics fields, and a multi-task joint inversion objective function of a shared underground electrical structure label is established; and performing inversion iteration by adopting maximum posteriori, updating parameters of the GMM prior model and the underground electrical structure label by adopting an expectation maximization algorithm until an end condition is met, and obtaining a joint inversion imaging result of the tunnel water-rich anomalous body. The advantages of a multi-source electrical method are fused, underground electrical structure priori is introduced, Bayesian uncertainty analysis is combined, and high-resolution and high-reliability recognition of the water-rich anomalous body in front of the tunnel is achieved.

The invention discloses a gallium oxide solar-blind ultraviolet detector based on selective area etching and a preparation method thereof, and belongs to the technical field of semiconductor photoelectric detection. Comprises from bottom to top: a substrate; the first epitaxial layer is located on the substrate, and the first epitaxial layer is a highly doped n-Ga2O3 layer; the second epitaxial layer is located on the first epitaxial layer, and the second epitaxial layer is a lightly doped n-Ga2O3 layer; the third epitaxial layer is located on the second epitaxial layer, the third epitaxial layer is a highly-doped p-NiO layer, and the third epitaxial layer is distributed at intervals through selective area etching; and the first ohmic contact layer is located on the area where the third epitaxial layer is distributed at intervals. The detector adopts a PN junction structure working in a reverse bias state, and compared with a Schottky structure, the detector has the advantages that the built-in electric field intensity and the leakage current level of a device are less affected by high-energy photon irradiation and working environment temperature change, and the anti-irradiation performance of the device and the working capability under an extreme temperature condition are effectively improved.

The invention provides an intelligent dust remover control method and system based on electrostatic adsorption. The method comprises the following steps: acquiring dust concentration, temperature and humidity and particulate matter impedance spectrum data of a working environment, screening key measurement points, applying an alternating electric field to obtain an impedance phase difference map, performing frequency spectrum consistency verification on the impedance phase difference map and the impedance spectrum data after temperature and humidity compensation, and calculating conductivity discrimination parameters of dust with different particle sizes; deploying a parallel metal plate adsorption array containing an insulating dielectric layer, and adjusting the plate spacing to change the electric field intensity; generating a resistivity space distribution thermodynamic diagram based on the conductivity discrimination parameters, and cooperating with drive board spacing adjustment and voltage output according to the resistance gradient change of the insulation and conductive dust gathering area and the migration path; and a measurement point location screening strategy is updated in combination with the spacing adjustment amplitude and the voltage change rate, and the impedance spectrum precision is optimized. Precise identification of insulation and conductivity multi-mode dust and dynamic electric field self-adaptive adsorption are achieved, the dust removal efficiency of a complex environment is improved, and energy consumption is reduced.

The invention discloses a gallium nitride power device and a preparation method thereof, and relates to a power semiconductor device, in order to simplify a forming process of a multilayer field plate, the invention provides the gallium nitride power device which is provided with a plurality of dielectric layers rising in a step shape, and a step-shaped side edge is formed on the side surface of each dielectric layer; according to the method provided by the invention, no matter how many layers of the field plates are, field plate deposition only needs to be carried out once, etching can be carried out twice and two layers of field plates can be formed during photoetching each time, the number of layers of the field plates can be increased without increasing the complexity and cost of the process, and the manufacturing cost of the field plates can be reduced. The electric field distribution between the gate metal and the drain metal of the device is more uniform, and the breakdown voltage and the reliability of the device are improved.

The invention discloses a copper wire tinning method for tinned copper stranded wire production, which relates to the technical field of metal surface treatment, and comprises the following steps: releasing a copper wire to an ionic liquid electrophoresis tank, applying an electric field to strip surface oxides, and then carrying out three-stage countercurrent rinsing to generate a clean copper wire; putting the clean copper wire into a composite plating tank, monitoring the tin liquid viscosity and the copper wire linear speed in real time, calculating the magnetic field gradient, and controlling tin crystal oriented growth according to the magnetic field gradient to generate an oriented crystallization tinned copper wire; the surface temperature of the directionally crystallized tinned copper wire is monitored in real time and compared with a preset temperature threshold value, a temperature permission trigger signal is generated, the annular array spray gun is triggered to work according to the temperature permission trigger signal, and a densified tinned copper wire is generated; and the densified tinned copper wire is scanned through a micro-focus CT scanner, a gap three-dimensional point cloud picture is generated, the gap size and the normal angle of the gap three-dimensional point cloud picture are analyzed, the optimal spraying parameters are recognized, and the passivation film tinned copper wire is generated.

The invention discloses an internal wave electromagnetic response numerical simulation method based on a layered ocean model. The method comprises the following steps: acquiring geomagnetic field parameters; calculating distribution characteristics of seawater conductivity along with depth, and dispersing the distribution characteristics into a layered ocean conductivity model; an internal wave mechanical model is constructed, internal wave velocity field distribution is established through characteristic parameters of internal waves, and dynamic input is provided for electromagnetic field response calculation; substituting the internal wave velocity field and the geomagnetic field into a Maxwell equation set, and constructing an internal wave induction electromagnetic field control equation; and applying tangential electric field continuity and normal current continuity conditions on a layered interface, and performing discrete and iterative solution on an equation by adopting a finite difference method to obtain distribution characteristics of the electric field and the magnetic field at different depths and frequencies. According to the method, the problem of insufficient precision caused by a uniform conductivity hypothesis is solved, and application limitation caused by an ideal geomagnetic field hypothesis is avoided, so that accurate simulation of internal wave induction electromagnetic response under a complex ocean condition can be realized.

The invention belongs to the field of power equipment monitoring, and discloses a lightning arrester on-line monitoring system and method based on non-contact differential electric field probe self-adaptive compensation, a non-contact differential voltage probe is adopted, the sensitivity to environmental noise and interference to other-phase high-voltage buses is remarkably reduced through differential measurement, and the monitoring accuracy is improved. And the self-adaptive compensation algorithm is combined, so that the measured signal can be corrected in real time according to the on-site electromagnetic environment change, the amplitude and phase distortion can be effectively inhibited, the accuracy and reliability of the high-voltage side bus voltage acquisition can be improved, and the overall monitoring precision can be obviously improved. According to the invention, high-sensitivity and wide-dynamic-range measurement of lightning arrester current is realized by adopting the fluxgate weak current sensor, accurate detection under small signals is guaranteed, and fine analysis of harmonic components is facilitated.

The invention provides a tank-type circuit breaker AC / DC voltage withstand test electric field improvement method and device and a storage medium, and the device comprises an epoxy resin composite insulator embedded with an aluminum alloy spherical shell, and the spherical shell achieves the equipotential connection with the wire outlet end of a circuit breaker sleeve through conical surface cooperation. And the curvature radius is optimally designed to transfer an electric field peak value to an equatorial region. The spherical shell is coated with a semi-conductive silicone rubber layer with resistivity distributed in a gradient manner, and the outer insulator forms a multi-stage umbrella skirt structure. During installation, dimensional tolerance self-adaptive compensation is achieved through a cam locking mechanism of the floating flange, and the belleville spring set provides axial sealing pre-tightening force. The method comprises four core processes of composite structure coaxial installation, gradient electric field regulation and control, dynamic sealing locking and electric heating state verification. According to the scheme, an electrode structure is reconstructed to suppress point discharge, space charge accumulation is blocked through dielectric layer resistivity gradient distribution, the creepage distance along the surface is prolonged through the multi-stage umbrella skirts, and the technical defect that the safety distance is shortened by a traditional grading ring is overcome.

The invention provides a power device failure positioning method and system based on multi-physics field coupling, and the method comprises the steps: applying dynamic electric stress to a tested power device, and synchronously collecting the thermal field data, electric field data and mechanical field data of the tested power device; wherein the thermal field data is used for representing the surface temperature distribution of the to-be-measured power device, the electric field data is used for representing the electrical parameters of the to-be-measured power device, and the mechanical field data is used for representing the internal morphology of the to-be-measured power device; synchronizing the thermal field data, the electric field data and the mechanical field data through timestamps, and aligning in a preset three-dimensional coordinate system to obtain multi-dimensional alignment data; and generating a failure probability distribution diagram according to the multi-dimensional alignment data so as to determine corresponding failure point coordinates. Through multi-physics field data coupling analysis, the problem of failure point fuzzy positioning in a complex packaging structure is solved, and the detection sensitivity under a dynamic working condition is improved.

The invention relates to the technical field of silicon carbide semiconductor devices, in particular to an integrally-formed equal-depth double-groove SiC MOSFET structure and a preparation method thereof. According to the structure, an N + buffer layer and an N-drift layer are sequentially formed on an N-type SiC substrate, and a main groove and an auxiliary groove which are consistent in depth are formed in the surface of the N-type SiC substrate; a gate oxide layer and a polycrystalline silicon gate are sequentially formed in the main groove, and the auxiliary groove is filled with a SiC epitaxial material which is doped with the drift layer in the same type, so that a charge compensation and electric field regulation and control unit is formed; the P-type body region surrounds the trench structure and forms an N + source region, and the drain electrode is formed through a back metallization process. Through the collaborative design of the equal-depth double grooves, the uniformization of electric field distribution is realized, the on-resistance and the switching loss are effectively reduced, the thermal stability and the reliability of the device are improved, the integrated process is adopted for integration, the process is simplified, the production efficiency and the yield are improved, and the semiconductor device is suitable for high-frequency and high-voltage application scenes and has a wide industrialization prospect.

Provided in the present disclosure is a ring main unit (500). The ring main unit (500) comprises a gas tank (100), a fixed frame (1) fixed to an inner side wall of the gas tank, and a circuit breaker switch (2) and a three-position switch (3) that are located in the gas tank (100). Embedded poles (21) of the circuit breaker switch (2) each comprise a pole body (211), and a moving-end shielding seat (212) and a fixed-end shielding seat (213) that are located at two ends of the pole body (211), wherein the moving-end shielding seat (212) and the fixed-end shielding seat (213) can respectively cover the two ends of the pole body (211), thereby electrically isolating an electrical connection position of the pole body (211) from the external environment. The pole body (211), the moving-end shielding seat (212) and the fixed-end shielding seat (213) are cast into a whole by means of an insulating resin, thereby improving the consistency of the poles. A grounding shielding seat (33) is made of an integrally formed metal member, such that a plurality of grounding contacts (32) can be uniformly enclosed within a shielding space (301), thereby optimizing the electric field distribution of the grounding contacts. The ring main unit (500) disclosed in the present application can not only use dry air as an insulating gas, but also achieves the miniaturization of the ring main unit (500) and satisfies the corresponding insulation performance.