837 results about "Shielding effect" patented technology

The invention is applicable to the field of photovoltaic technology, and provides a back contact solar cell, which comprises a silicon substrate, non-recessed areas and recessed areas are alternately arranged on the backlight surface of the silicon substrate, and the silicon substrate is provided with extending parts extending and protruding to the upper parts of the recessed areas at the edges of the non-recessed areas and the recessed areas; the first dielectric layer and the first polarity doping layer are sequentially stacked on the non-sunken region and the extension part; the second dielectric layer comprises a first part stacked on the first polarity doping layer and a second part stacked in the sunken region; the second polarity doped layer is stacked on the first portion and the second portion. Under the shielding effect of the extension part, the first polarity doping layer in the non-recessed area is effectively isolated from the second polarity doping layer in the recessed area, and electric leakage is avoided.

The invention discloses an enclosure system of a low-temperature storage tank and transportation equipment, and relates to the technical field of fluid transportation, the enclosure system is installed on the inner wall of the low-temperature storage tank, the enclosure system comprises a plurality of heat insulation modules installed on the inner wall of the storage tank, the heat insulation modules are spliced and cover at least part of the inner wall of the storage tank, and the heat insulation modules are arranged on the inner wall of the storage tank; assembling grooves are formed in the splicing positions of the heat insulation modules; the bridging blocks are installed in the assembling grooves, and every two adjacent heat insulation modules can be connected together through the corresponding bridging blocks; the shielding module is connected with the heat insulation module, the shielding module comprises a first shielding layer, a second shielding layer and a third assembly plate, the first shielding layer and the second shielding layer are arranged in a spaced mode, and the third assembly plate is located between the first shielding layer and the second shielding layer. According to the invention, a better shielding effect can be realized by arranging two or more shielding layers, and the first shielding layer and the second shielding layer are arranged at intervals, so that the capacitive coupling effect between the shielding layers is reduced, and the penetrating power of electromagnetic waves is reduced.

The invention relates to the technical field of electromagnetic compatibility, in particular to a power application environment electromagnetic interference analysis and evaluation method and system, and the method comprises the following steps: recording the position coordinates of a plurality of power devices based on power grid operation data, collecting the current and voltage data of the operation of the devices, and measuring the electromagnetic field intensity data of a plurality of positions of a power grid; an electromagnetic environment data set is generated. According to the method, the operation data and the electromagnetic field intensity of the power equipment are recorded, the understanding ability of the electromagnetic environment is enhanced, the shielding effect of various materials is accurately evaluated by combining the analysis of the shielding materials, the design and operation of the power equipment are optimized, and the electromagnetic sensitivity of the equipment is evaluated. According to the method, the dynamic distribution of the electromagnetic field is simulated and predicted, the electromagnetic field mode causing a fault is identified, and risk equipment predicted through real-time monitoring and data analysis is combined, so that the stability and safety of a power system are improved, the anti-interference capability is enhanced, and the operation efficiency and function safety of power facilities are improved.

The invention provides a modified basalt fiber, a basalt fiber shielding material and a preparation method, and relates to the technical field of fiber composites.The modified basalt fiber comprises an activated basalt fiber, an adhesion layer and an electromagnetic shielding layer, and the surface of the activated basalt fiber is sequentially coated with the adhesion layer and the electromagnetic shielding layer; the adhesion layer comprises polydopamine; the electromagnetic shielding layer comprises magnetic Fe3O4 nano particles and a graphene nano sheet; the mass ratio of the activated basalt fibers to the polydopamine to the magnetic Fe3O4 nanoparticles to the graphene nanosheets is 1 to (0.4 to 0.5) to (0.6 to 1) to (0.1 to 0.25). According to the basalt fiber shielding material provided by the invention, the conductive particles and the magnetic particles are combined, and by optimizing the material components and proportion, a very good electromagnetic wave absorption and shielding effect can be achieved, a wider frequency band shielding effect can be provided, and electromagnetic radiation in various frequency ranges can be effectively covered.

The invention discloses a composite shielding material effect experiment data analysis method, and particularly relates to the field of material shielding effect analysis, and the method comprises the following steps: measuring key data such as dielectric constant, magnetic conductivity, conductivity and thickness of each layer of a composite shielding material through an electromagnetic performance measurement instrument; establishing an electromagnetic wave propagation model for describing propagation of electromagnetic waves in the multilayer medium based on a Maxwell equation, and defining boundary conditions of a test sample; time domain and frequency domain characteristics of an electromagnetic interference source are simulated through Fourier transform, and actual input interference is simulated. And analyzing the dynamic response of the electromagnetic wave propagation model under transient and steady-state interference signals to form an electromagnetic wave interference response propagation model. Through comparison with actual shielding effectiveness test data, model parameters are adjusted, and it is ensured that model calculation errors are within an acceptable range. A full-band shielding effectiveness prediction map of the composite shielding material is generated based on the model, and theoretical support is provided for material design and optimization.

The invention relates to the technical field of fusion devices, and discloses a flange structure of a cold shield sector of a nuclear fusion device, the cold shield device and the nuclear fusion device, and the flange structure of the cold shield sector of the nuclear fusion device comprises a first panel; the second panel and the first panel are arranged at an interval; the flanging assembly is arranged between the first panel and the second panel and comprises a first flanging and a second flanging, the first flanging is connected with the first panel, the second flanging comprises a main body part and a flat plate part which are connected, the main body part is connected with the second panel, and the flat plate part is arranged at the ends, away from the second panel, of the main body part and the first flanging; the surface, opposite to the second panel, of the flat plate part is a polished surface; the connecting piece is connected with the first flange and the second flange in a fastening manner; and the first insulating part is arranged between the first flange and the second flange in an insulating manner. According to the flange structure of the cold shield sector of the nuclear fusion device, the heat shielding effect can be improved, and the heat radiation influence on low-temperature components is reduced.

The invention discloses an IGBT (Insulated Gate Bipolar Translator) device, which comprises a plurality of gate trench structures and emitter trench structures, wherein the gate trench structures and the emitter trench structures are arranged in parallel and penetrate through a well region. The gate conductive material layer is connected to the gate. The emitter conductive material layer is connected with the emitter. A drift region is formed at the bottom of the well region, and a collector region is formed at the bottom of the drift region. An emitter region is formed in a surface region of a selected region of the well region. The emitter regions are located on the two sides of each gate trench structure and are self-aligned with the side faces of the gate trench structures. The emitter region is not in contact with the side surface of the emitter trench structure. The emitter trench structure serves as a shielding structure of the gate trench structure to reduce Cgc, the depth of the emitter trench is larger than that of the gate trench, and the shielding effect on the gate trench structure is improved by increasing the depth of the emitter trench. According to the invention, Cgc can be reduced.

The present invention discloses an electromagnetic shielding film and a circuit board. The electromagnetic shielding film comprises: a first shielding layer, an interlayer and a second shielding layer which are stacked in sequence; the thickness of the first shielding layer, the thickness of the second shielding layer and the thickness of the interlayer satisfy: 0.05≤d3 / (d1+d2)≤6.5. The interlayer is provided to increase the flexibility of the electromagnetic shielding film, and the provision of two shielding layers further enhances the shielding effect. The ratio of the thickness of the interlayer to the sum of the thickness of the two shielding layers is limited within a certain range, so that the thickness of the interlayer is within a suitable thickness range, which can have better stress, the device is resistant to bending, and the overall thickness of the electromagnetic shielding film is not too thick, which is conducive to the thinning of the device. At the same time, the thickness of the interlayer is relatively close to the sum of the thicknesses of the two shielding layers, which improves the stress transmission performance, makes the stress transmission more uniform, and avoids the breakage of the electromagnetic shielding film.

The invention relates to a high-field animal magnetic resonance imaging superconducting magnet, a gradient coil and a decoupling method. Wherein the superconducting magnet comprises two main coils, four adjusting coils and three shielding coils, and nine first-order, second-order and third-order axial superconducting shimming coils are arranged in the superconducting magnet; the gradient coil comprises an active shielding magnetic field coding coil and further comprises 11 coils in the zero-order axial direction, the second-order axial direction, the third-order axial direction and the fourth-order axial direction. Electromagnetic coupling and mechanical coupling between the superconducting magnet and the gradient coil are optimized, the basic judgment standard is that the minimum distance between coil wires is appropriate, engineering processing is feasible, and therefore the minimum stray magnetic field of the gradient coil and the minimum electromagnetic Lorentz force are obtained. Cooperative stable operation can be guaranteed without additional connection processing between the two functional parts. The superconducting magnet shielding effect is excellent, the gradient coil shielding effect is excellent, and strong Lorentz force coupling between the superconducting magnet and the gradient coil is effectively eliminated.

The invention relates to an electromagnetic shielding film and a circuit board, and the electromagnetic shielding film comprises a shielding layer, the thickness d of the shielding layer in a slicing state and in a preset observation range satisfies # imgabs0 #, the thickness uniformity of the shielding layer is less than or equal to 20% through the modes of adjusting a production technology and the like, the shielding layer with uniform thickness is formed, the consistency of impedance characteristics can be improved, and the electromagnetic shielding film has good electromagnetic shielding performance. And meanwhile, the skin effect of the shielding layer is reduced, the surface current is better borne, the influence of electromagnetic interference of a high-frequency and high-speed line on an internal circuit is reduced, the shielding effect of the electromagnetic shielding film on the high-frequency and high-speed line is improved, and the working reliability of the circuit board is further improved. Besides, the first protection layer forms an undulating surface through the particle member, and the shielding layer conformal to the undulating surface of the first protection layer can be grounded with the circuit board by using a downward projection, so that non-conductive particle grounding is realized, more use scenes are satisfied, and the material applicability is improved.

A self-adaptive electromagnetic interference shielding and signal enhancement system belongs to the field of electronics and communication and comprises a signal feature analysis module, a dynamic shielding design module, a signal enhancement module, an intelligent adjustment module and a feedback adjustment module. According to the invention, the shielding effect and the signal enhancement strategy can be dynamically adjusted according to the change of the real-time electromagnetic environment. The intensity, the frequency and the position of an interference signal are monitored in real time through spectrum analysis and a multi-mode sensing technology. An intelligent material or a tunable structure is used to dynamically adjust electromagnetic parameters of a shielding material, and an efficient shielding effect is achieved. Various types of electromagnetic interferences, including high-frequency, low-frequency and transient interferences, can be effectively suppressed. Through a multi-sensor fusion technology, types and features of interference sources are accurately identified, and targeted shielding is realized. In a complex electromagnetic environment, a plurality of interference sources can be processed at the same time, and signal distortion or loss is avoided.

The present invention relates to the field of high-rate mobile wireless communications. Disclosed are a multi-frequency multi-polarized wide-beam scanning base station system, and an optimization design method. The method comprises: on the basis of an aperture field expansion theory and a mode coupling theory, designing a conical horn feed source antenna capable of radiating a Gaussian fundamental mode beam, and providing a stable beam width and a stable phase center; designing a beam separation device based on a periodic structure, wherein the beam separation device includes band-pass frequency selective surfaces and a linear polarization grid; and combining front-end quasi-optical links of multiple frequency channels and multiple polarized channels, so as to increase the bandwidth and communication rate of a base station antenna. In the present invention, a genetic optimization algorithm is combined with reflector shaping, thereby effectively reducing the conflict between a shielding effect of a dual-reflector antenna and a scanning angle, and realizing the multiplication of a beam scanning angle.

The invention relates to the technical field of laser micromachining, in particular to a laser ablation titanium alloy numerical simulation method based on a plasma shielding effect. In order to solve the problems that the precision and efficiency of an existing laser processing and manufacturing micro-nano structure are low, the plasma shielding effect is not fully considered in a simulation model and the like, two-dimensional and three-dimensional models are constructed by means of COMSOL Multiphysics software. According to the model, the plasma shielding effect is fully considered, a laser energy transfer equation is corrected, and the molten pool behavior and surface topography forming process is simulated by combining mass, momentum and energy conservation equations. A laser ablation process is accurately simulated by setting a heat source and boundary conditions, applying a level set method, considering various effects and calculating plasma related parameters. And inputting different laser parameters to simulate and analyze the influence on the groove morphology, and comparing an experiment with a simulation result to correct the model. Simulation precision is improved, laser processing parameters can be optimized, cost is reduced, universality is high, theoretical guidance can be provided for laser processing of various metal materials, and the laser processing technology is promoted to be developed in multiple fields.

The invention discloses a test system and method for providing a large weak magnetic space based on a high-frequency magnetic field, relates to the technical field of magnetic shielding coefficient test of a magnetic shielding space, and mainly aims to solve the problems that the internal space of existing equipment for providing the weak magnetic space is small; the system comprises a high-frequency magnetic field emission module, a magnetic field intensity acquisition module and a passive magnetic shielding assembly. The high-frequency magnetic field transmitting module comprises at least one pair of large coils with the same number of winding turns, and the large coils are coaxially arranged in parallel and used for transmitting a high-frequency magnetic field to the passive magnetic shielding assembly; the passive magnetic shielding assembly provides a weak magnetic space after performing a magnetic shielding effect on the high-frequency magnetic field; and the magnetic field intensity acquisition module is used for acquiring and recording the magnetic field intensity in the weak magnetic space in the passive magnetic shielding assembly.

The invention relates to a large-size double-layer splicing type ferrite magnetic shielding structure, in particular to a low-noise magnetic shielding barrel structure which is particularly suitable for an ultra-high sensitive magnetic field and inertial measurement device and miniaturization integration application of the ultra-high sensitive magnetic field and inertial measurement device. The magnetic shielding barrel is manufactured by splicing single large-size ferrite blocks into a double-layer cylinder. And the seam at the splicing part of the inner layer is blocked by the ferrite on the outer layer, so that the splicing does not generate large magnetic flux leakage. The double-layer configuration improves the shielding coefficient and reduces the magnetic noise at the same time. The novel large-size double-layer splicing type ferrite magnetic shielding structure shielding barrel is simple in processing technology, the shielding effect is not affected while the material cost is saved, the magnetic noise is reduced through the double-layer barrel structure, and the defect that the magnetic noise caused by a traditional single-layer ferrite magnetic shielding barrel cannot be further reduced is overcome.

The invention provides a blazed grating manufacturing method, which comprises the following steps: providing a substrate, covering the substrate with periodically arranged masks, and etching the substrate by utilizing an incident angle and a rotation angle, taking the masks as a mask and utilizing an ion beam to form a blazed grating. The incident angle is the angle between the first projection of the ion beam on the plane where the normal of the substrate is located and the normal of the substrate, the rotation angle is the angle between the second projection of the ion beam on the plane where the surface of the substrate is located and the tangent line of the surface of the substrate, and the anti-blazing angle of the blazed grating is determined according to the incident angle and the rotation angle. Therefore, the shielding effect of the mask can be reduced by using the incident angle and the rotation angle, so that the purpose of controlling the angle of the anti-blazing angle is achieved, the angle of the anti-blazing angle is controllable, the angle of the anti-blazing angle is increased by controlling the incident angle and the rotation angle, and finally the diffraction efficiency of the blazed grating is improved.

The invention provides a magnetic shielding box for weak magnetic signal measurement and a shielding effectiveness estimation method. The magnetic shielding box comprises a non-magnetic supporting frame and a shielding mechanism. The non-magnetic supporting frame is a cuboid, is at least arranged along the edges of the cuboid and is used for supporting the shielding mechanism, and the interior of the non-magnetic supporting frame is hollow so as to accommodate an object to be detected; the shielding mechanism at least comprises N layers of plate layer structures, plate layer fixing pieces and plate layer supporting pieces; the plate layer structures are sequentially arranged outside the non-magnetic supporting frame in a sleeving mode so as to isolate an external magnetic field of the magnetic shielding box. The plate layer fixing piece sequentially penetrates through all the plate layer structures and is fixedly embedded into the non-magnetic supporting frame. The plate layer supporting pieces are at least arranged between the two adjacent plate layer structures and used for controlling the distance between the two adjacent plate layer structures. N is an integer greater than or equal to 2. The problem of complex manufacturing of the magnetic shielding box can be solved, and the shielding effects of different frequency bands are ensured.

The invention relates to the technical field of connectors, and particularly discloses a connector with a shielding function, which comprises a shell and a circuit board accommodated in the shell, the circuit board is provided with conductive welding spots and a grounding part, the circuit board is connected with an external cable through a conductive group, the circuit board is provided with a housing used for separating the plurality of conductive welding spots, the housing is provided with a shielding assembly used for covering the conductive welding spots, and the shielding assembly comprises a cover body made of a magnetic isolation material. The arrangement of the housing can effectively separate and protect a plurality of conductive welding spots on the circuit board, prevents short circuit or mutual interference among the conductive welding spots, improves the reliability and stability of the circuit board, and the shielding assembly can further enhance the protection of the conductive welding spots, reduces the interference of an external electromagnetic field on the conductive welding spots through the shielding effect, and improves the reliability of the circuit board. And meanwhile, an electromagnetic field generated by the conductive welding spot is prevented from influencing the external environment.

The invention provides a floating nuclear power platform and a radiation shielding system thereof. The radiation shielding system comprises a primary shielding structure, a combined shielding structure and a containment shielding structure, the primary shielding structure covers the outer side of a reactor pressure vessel to perform primary shielding on the reactor pressure vessel, the combined shielding structure sleeves a loop pipeline and accessory equipment thereof, and the containment shielding structure is arranged in the containment structure; the primary shielding structure comprises a first heat preservation layer wrapping the outer side of the pressure vessel shell, a shielding water tank covering the first heat preservation layer and a shielding material layer covering the outer side of the shielding water tank, and the shielding water tank is hollow to contain water. The combined shielding structure comprises a high-density alloy layer and a second thermal insulation layer; the high-density alloy layer is sleeved outside the loop pipeline and accessory equipment thereof; the second thermal insulation layer is sleeved outside the high-density alloy layer; the containment shielding structure comprises a lead plate, a polyethylene plate layer, a boron-containing polyethylene plate layer and an outer steel plate layer which are arranged in the containment structure. According to the radiation shielding system provided by the invention, the total radiation shielding weight can be reduced by 20-40% while the radiation shielding effect is guaranteed.

The present application provides an annular lining apparatus, a liner, a process chamber, and a semiconductor process device. The annular lining apparatus is used for the process chamber and comprises a first annular lining, a cylindrical lining, and a second annular lining, wherein the first annular lining is connected to a first end of the cylindrical lining, the second annular lining is connected to a second end of the cylindrical lining, and the cylindrical lining is telescopic in the axis direction thereof. The described solution can solve the problem of a poor shielding effect due to poor grounding electrical connection of the liner of the process chamber involved in the related technology.

The invention provides a piston type shielding door, and particularly relates to the technical field of radiation shielding, the piston type shielding door comprises a door frame, and the door frame is mounted on a wall body. The upper portion of the side, facing the door frame, of the door body and the left side and the right side, close to the door frame, of the door body are concave inwards to form stepped structures, the moving direction of the door body is perpendicular to the wall, and the door frame is matched with the door body to form labyrinth seal. And the sliding device is fixedly mounted at the bottom of the door body. And the bearing device is mounted on the ground at the bottom of the door body, and the bearing device is interactively matched with the sliding device. And the driving device is fixedly installed on the side, away from the door frame, of the door body, and the driving device is used for driving the door body to move on the bearing device through the sliding device. According to the piston type shielding door, the technical problems that a shielding door is poor in shielding effect, high in construction requirement and serious in abrasion of internal parts are solved, and the piston type shielding door is complete in shielding, low in construction difficulty and long in service life.

The utility model relates to the field of electromagnetic shielding films, in particular to an electromagnetic shielding film, which comprises a multi-layer composite structure and is characterized in that the electromagnetic shielding film is formed by compounding at least four layers of materials, namely a base material layer 1, a conductive grid layer 2, an electromagnetic absorption layer 3 and a protective layer 4 in sequence; the base material layer 1 adopts a light high-strength polymer film as a substrate and has excellent flexibility and mechanical strength; the conductive grid layer 2 is located on the base material layer 1, is of a grid structure formed by fine metal wires or high-conductivity polymer fibers, is formed through a precise weaving or printing technology and is used for guiding and dispersing electromagnetic wave energy; the technical problem that the service life and the shielding effect of the electromagnetic shielding film are affected due to the fact that the electromagnetic shielding film is prone to abrasion, scraping and the like in the long-term use process is solved.

The invention discloses an electric leakage detection method of an explosion-proof distribution box, particularly relates to the technical field of electric power safety in flammable and explosive environments, and is used for solving the problems of electric leakage signal attenuation and insufficient detection sensitivity caused by an eddy current effect of a metal explosion-proof shell. An original electric leakage signal of a wire in a box is obtained, and an eddy current compensation factor is constructed based on the material and thickness of a shell to carry out gain compensation; shell surface temperature distribution and three-dimensional magnetic field components are synchronously collected, and a compensation failure state is judged through collaborative analysis of high-temperature area migration acceleration and magnetic field polarization angle offset; when the compensation is effective, the area score of the space magnetic field rotation on the surface of the shell is calculated, and when the time change gradient exceeds a preset threshold value, the tripping action is triggered, the shielding effect of shell eddy current on weak electric leakage signals is broken through, and high-sensitivity electric leakage protection is realized while the explosion-proof integrity is maintained.

The invention provides an infrared shielding flexible composite phase change film and a preparation method thereof. The composite phase change film is a flexible composite film material synthesized by taking a cellulose acetate porous film as a framework and a phase change material as a core material and doping a high-reflectivity nanoparticle material. The preparation method of the composite phase change membrane comprises the following steps: forming pores by a phase inversion method, carrying out gravity settling to obtain a cellulose acetate porous membrane with low emissivity, and dipping to obtain the flexible composite phase change membrane. The prepared flexible composite phase change film is a bendable film with certain mechanical strength, the system has the infrared emissivity reducing performance and the temperature control performance, and the composite phase change material under the dual-mode function can efficiently achieve the infrared shielding effect.

The utility model discloses a protection box for high magnetic field chip test, which is used for installing a chip test carrier plate and comprises a shielding box body and an end cover, an accommodating cavity is arranged in the shielding box body, at least one end of the accommodating cavity is open, and the end cover is detachably and fixedly connected to one side of the opening of the accommodating cavity. The end cover is provided with a through groove corresponding to an opening of the containing cavity, the wall of the containing groove is provided with a clamping groove, the groove wall of the through groove is provided with a slot corresponding to the clamping groove, one end, provided with an electronic component, of the chip testing carrier plate penetrates through the slot and then is inserted into the clamping groove, and one end, provided with a chip to be tested, of the chip testing carrier plate is located outside the shielding box body. According to the protection box for the high-magnetic-field chip test, the magnetic shielding effect on the electronic components can be realized only by inserting the electronic components on the chip test carrier plate into the clamping grooves of the shielding box body in a matched manner, the operation is simple, the installation is convenient, and the test efficiency is greatly improved.

The invention particularly relates to a method for determining a magnetic shielding body material of an optical fiber ring, and solves the technical problems that the magnetic shielding effect is poor and the magnetic shielding performance requirement of an optical fiber gyroscope is difficult to meet due to the lack of an optimal selection method for a magnetic shielding body in the prior art. The invention discloses a method for determining a magnetic shielding body material of an optical fiber ring. The method comprises the following steps: 1) calculating relative permeability of each magnetic shielding material under different magnetic induction intensities; 2) establishing an optical fiber ring magnetic shielding simulation model; 3) simulating to obtain first magnetic induction intensity of a magnetic field environment where the optical fiber ring is located; 4) selecting the material of the magnetic shielding body on the outermost layer; and 5) performing simulation in sequence from outside to inside to obtain the magnetic induction intensity of the magnetic field environment where the optical fiber ring is located, and based on the magnetic induction intensity, selecting the magnetic shielding material with the highest relative magnetic conductivity in the multiple magnetic shielding materials in the step 1) in sequence as the material of the magnetic shielding body of the corresponding shielding layer until the material of each layer of magnetic shielding body in the optical fiber ring is determined.

The utility model relates to a 5G communication device shielding shell, which comprises a shielding shell body and a shielding cover body, the shielding cover body is detachably connected to the open end of the shielding shell body, and the bottom wall in the shielding shell body is provided with two groups of circuit shielding walls, output shielding walls, input shielding walls and line shielding grooves which are arranged at intervals. The left side wall of the shielding shell is provided with three signal output interfaces, and the right side wall of the shielding shell is provided with two signal input interfaces; each group of circuit shielding walls comprises a plurality of circuit shielding walls which are sequentially arranged in parallel, and the circuit shielding walls extend in the left-right direction; an input shielding wall is arranged between the two signal input interfaces, and output shielding walls are respectively arranged at positions directly facing the two signal output interfaces; the top ends of the circuit shielding wall, the output shielding wall and the input shielding wall abut against the inner surface of the shielding cover body. According to the utility model, a plurality of relatively closed small shielding cavities are formed in the shielding shell, the structure is compact, and the shielding effect is good.

The invention relates to an electric leakage suppression system for an alternating-current power system, and the system comprises a variable-frequency compensation control module which adjusts the frequency and signal amplitude in a circuit according to the equipotential characteristics of a power utilization loop of the power system, so as to match the load characteristics and achieve the dynamic fixation of the signal amplitude; the real-time monitoring module is used for monitoring the frequency, current and voltage of the power system; the central processing unit is used for processing data from the monitoring module, executing data analysis and identifying frequency and current changes under the condition of electric leakage or electric shock; and the electric leakage suppression module is connected with the real-time monitoring module, is provided with a mechanism which is automatically activated when frequency and current are detected to be abnormal, and is used for dynamically adjusting circuit response to suppress leakage current. And the modules are connected in parallel to the power utilization loop, perform rapid self-adaptive modified modulation compensation on the parallel frequency resonance of the load loop, and dynamically adjust the current phase and amplitude so as to realize the zero potential difference of the target load end and the current suppression on the target load, and form the suppression and shielding effects on the leakage of the circuit.

The invention discloses a ferromagnetic material internal defect leakage magnetic field increasing method based on alternating current and direct current composite magnetization, which comprises the following steps of: fixing a workpiece at the center of a composite exciting coil, and synchronously applying direct current and high-frequency alternating current; after pure direct current magnetization is saturated, current is locked, and a basic leakage magnetic field is established; the surface magnetic conductivity is dynamically reduced by overlapping alternating current, and the magnetic shielding effect is weakened; a leakage magnetic field signal is scanned and collected through a differential Hall sensor array, and background magnetic field deduction, peak value comparison and adaptive filtering processing are carried out; and determining an optimal magnetization parameter combination by adopting a gradient descent method and Bayesian optimization. The system is integrated with a composite excitation coil and a signal conditioning unit, so that synchronous excitation, signal acquisition and real-time analysis are realized. The leakage magnetic field signal at the deep defect is enhanced through alternating-current and direct-current composite magnetization, the problem of signal weakening caused by traditional direct-current saturation is solved, the defect detection sensitivity and efficiency are improved, and the method is suitable for non-destructive detection scenes of ferromagnetic materials.

The invention provides a manufacturing method of a fan-out type packaging structure and the fan-out type packaging structure, the fan-out type packaging structure comprises a rewiring layer, at least one plastic packaging layer, at least one first shielding layer, at least one chip and at least one electric connecting piece, the rewiring layer comprises a grounding circuit layer, the chip and the electric connecting piece are arranged on the first surface of the rewiring layer, and the grounding circuit layer is arranged on the second surface of the rewiring layer. The electric connecting piece is positioned on the outer side of the chip and is electrically connected to the grounding circuit layer; the plastic packaging layer is arranged on the first surface of the rewiring layer and packages the electric connecting piece and the chip; the first shielding layer at least partially covers the side surface of the plastic package layer; at least part of the electric connecting piece is exposed out of the side face of the plastic packaging layer and is electrically connected to the first shielding layer, and the first shielding layer and the grounding circuit layer are electrically conducted through the electric connecting piece. The first shielding layer is connected to the grounding line layer through the electric connecting piece, so that the electric connecting piece can be utilized to realize relatively large-area surface contact with the first shielding layer and the grounding line layer respectively, the resistance among the three layers is reduced, and the shielding effect is improved.