1030 results about "Dielectric loss" patented technology

The invention relates to the technical field of bushing detection, and discloses a bushing insulation state detection method based on multi-parameter real-time monitoring. The method comprises the following steps: acquiring multi-dimensional monitoring data such as a partial discharge pulse sequence, dielectric loss angle tangent value fluctuation data and surface leakage current density distribution in a bushing operation environment in real time; carrying out insulation defect feature extraction on the data set, and generating an insulation defect distribution map containing a creeping discharge track, an internal air gap position mark and a carbonization channel density index; high-risk and potential defect areas are divided by adopting a dynamic threshold segmentation algorithm, boundary coordinates are determined, and an insulation state evaluation vector containing parameters such as a surface discharge intensity index and the like is constructed according to the boundary coordinates; and inputting the vector into a pre-trained insulation aging prediction model, and outputting a bushing residual insulation life estimated value and a defect development priority sequence. According to the method, all-around accurate monitoring and pre-judgment of the insulation state of the sleeve are achieved, and scientific support is provided for operation and maintenance decision making of the sleeve.

The invention provides a manufacturing method of an ultra-low dielectric loss high-speed copper-clad plate, which comprises the following steps of: constructing a physical coupling model of a multi-zone independent temperature control module and an electro-thermal conductivity adjusting layer based on the thickness of the copper-clad plate and a thermal response parameter of a resin system; space and time dynamic distribution of heating area power and heat conductivity is achieved; a dynamic thermal boundary regulation and control algorithm, finite element simulation and self-adaptive PID feedback are fused, real-time monitoring and deviation compensation of a temperature field are carried out through infrared thermal imaging and edge calculation, heating and heat dissipation strategies are cooperatively adjusted, a heat flow path can be actively guided, the uniformity of thermal stress distribution and the structural stability are achieved, and the method is suitable for large-scale popularization and application. And the thermal management efficiency of the copper-clad plate in a complex manufacturing environment is improved.

The invention relates to the technical field of electrical equipment insulation performance detection, in particular to an insulating oil dielectric loss test system based on temperature compensation, which comprises a temperature acquisition module for acquiring insulating oil temperature data and environment temperature data; the dielectric loss measurement module measures a dielectric loss value and a dielectric loss angle through a self-adaptive anti-interference algorithm, and synchronously records voltage and frequency; the intelligent compensation module matches temperature characteristic parameters for different temperature intervals, and compensates a dielectric loss detection value through a segmented temperature compensation model; the state analysis module judges the aging degree and state of the insulating oil according to the compensated dielectric loss value and acid value, generates a multi-stage early warning signal and a diagnosis report by combining the breakdown voltage and the moisture content, and dynamically adjusts the test frequency according to the oil sample type and the operating age limit; and the cloud management platform stores historical data and compensation parameters, establishes a performance degradation model, analyzes a dielectric loss trend and generates maintenance suggestions. Therefore, the problems of insufficient test precision, poor environmental adaptability and the like in the prior art are solved.

The application discloses a MnFe2O4 / GO wave-absorbing aerogel with a directional aperture structure and a preparation method thereof, belongs to the technical field of wave-absorbing material preparation, and is characterized in that manganese ferrite (MnFe2O4) magnetic particles are uniformly loaded on the surface of graphene to obtain a graphene aerogel with a three-dimensional loose porous structure and magnetic particle assembly; the MnFe2O4 is prepared by using a low-temperature co-precipitation method, and the MnFe2O4 / GO wave-absorbing aerogel is prepared by combining directional freezing and heat treatment, and the method is mild and simple. The application improves the impedance mismatch problem of the graphene material, enhances the magnetic loss of the material, and obtains a novel porous aerogel wave-absorbing material which has both dielectric loss and magnetic loss by introducing the manganese ferrite.

The invention provides a high-dielectric low-loss X7P type dielectric ceramic material and a preparation method and application thereof, and relates to the technical field of functional ceramic materials, the dielectric ceramic material is composed of a perovskite type compound as a main component and an auxiliary component; wherein the perovskite type compound contains a Ba element and a Ti element, and the auxiliary components comprise a first auxiliary component containing an Mg element, a second auxiliary component containing SiO2, a third auxiliary component containing an Mn element and a fourth auxiliary component containing a rare earth element R. According to the invention, barium titanate is doped and modified, so that the excellent performance of combining different compounds is realized, the dielectric constant and temperature stability of the dielectric ceramic material are improved, and the dielectric loss is reduced.

The invention relates to the technical field of wave-absorbing materials, in particular to a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material. The invention provides a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material, which comprises the following steps of: etching titanium aluminum carbide powder through a LiF / HCl mixture, and performing ultrasonic stripping to prepare a uniform dispersion of MXene nanosheets; the preparation method comprises the following steps: dispersing MXene nanosheets in a solution of water and absolute ethyl alcohol, and adding a pyrrole monomer and a FeCl3. 6H2O aqueous solution for reaction; after the reaction, washing is performed to obtain a PPy-MXene composite material; the preparation method comprises the following steps: by taking NiCl2. 6H2O as a nickel source and sodium oxalate as a precipitator, preparing NiO nanowires by adopting a hydrothermal method combined with a calcining process; the invention discloses a preparation method of an MXene-NiO-PPy ternary composite wave-absorbing material.According to the method, the MXene-NiO-PPy ternary composite wave-absorbing material with rich heterogeneous interfaces and a porous micro-nano structure is constructed, cooperation of dielectric loss, magnetic loss and interface polarization loss is achieved, and finally the light, efficient and broadband wave-absorbing performance is obtained.

The invention discloses a 3D packaging structure and a manufacturing method thereof, and the method employs a glass wafer as a first carrier plate, and solves the problems of reliability and signal interference caused by the mismatching of thermal expansion coefficients of an organic material adapter plate and a Si-based silicon bridge chip. In S1, a blind hole is etched by taking a glass wafer as a base material, and Cu is metallized and filled, and the thermal expansion coefficient of glass is similar to that of a silicon bridge, so that the risk of thermal stress deformation is reduced. And S2, through groove etching, temporary carrier plate bonding and thinning, a through groove hole is formed, and the rigid structure of the glass carrier plate maintains the stability of the packaging structure during high-density integration. And S3, the silicon bridge Die is embedded into the through groove hole, the low thermal expansion characteristic of the glass is well matched with the silicon bridge, the interface stress is reduced, the dielectric property of the glass support plate is excellent, the signal dielectric loss is reduced, and the signal integrity is improved by matching with the silicon bridge Die. And S4, after the functional chip is mounted on the adapter plate, the glass-based adapter plate ensures reliable connection, signal attenuation distortion is inhibited, and a reliable packaging scheme is provided for high-density integration.

The invention relates to a low-dielectric-loss high-thermal-conductivity epoxy resin composite material and a preparation method thereof, and the preparation method comprises the following steps: carrying out surface modification treatment on a thermal conductive filler: carrying out surface modification on the thermal conductive filler by adopting a chemical covalent bonding or physical adsorption mode, the heat-conducting filler is used for improving the compatibility of the filler and an epoxy resin matrix and reducing the interface thermal resistance, and comprises boron nitride with a two-dimensional sheet structure; epoxy resin, a curing agent and an optional modifier are evenly mixed, the epoxy resin is selected from epoxy resin with the low polarity characteristic, and the modifier comprises at least one of thermoplastic resin or elastomer. And the process is simple and controllable.

The invention relates to a modified silicon carbide fiber and a preparation method and application thereof, the modified silicon carbide fiber endows magnetic loss, and combines high strength and corrosion resistance of a geopolymer matrix to realize double improvement of mechanical properties and wave absorbing efficiency of concrete. Carbon fibers in conventional wave-absorbing concrete are replaced by modified silicon carbide fibers, so that on one hand, the wave-absorbing concrete has good oxidation resistance at high temperature, carbon emission is greatly reduced, and the wave-absorbing concrete has the advantages of energy conservation and environmental protection; and on the other hand, the defect that the performance is reduced at high temperature is overcome, and the modified silicon carbide fiber enables the magnetic loss of metal and the dielectric loss of a matrix to form a synergistic effect, so that the wave absorbing performance is greatly improved. The invention is suitable for green communication infrastructures, and has the characteristics of environmental protection, high durability and broadband wave absorption.

The invention discloses a broadband dual-circularly-polarized low-cost phased-array antenna array element, which comprises an antenna radiation structure and a slot feed structure which are arranged independently from each other, and is characterized in that the antenna radiation structure comprises a parasitic radiation layer, a first dielectric substrate, an excitation radiation layer and a second dielectric substrate which are arranged in a laminated manner; the slot feed structure comprises a slot layer, a third dielectric substrate, a strip-shaped transmission line and a fourth dielectric substrate; the antenna layer structure and the slot feed structure realize electromagnetic coupling transmission through the slot layer; a hollow symmetrical structure is arranged in the middle of the first dielectric substrate, and the hollow part is used as an air medium to reduce dielectric loss; the gap layer is provided with a multidirectional coupling gap structure; the strip-shaped transmission line is provided with at least two feed ports, and dual circularly polarized radiation is formed in the antenna layer structure through excitation of different feed ports. The antenna radiation layer has no metal through hole or blind hole, can be processed in a layered manner, has the advantages of low processing cost and high yield, and ensures impedance bandwidth while realizing dual circular polarization.

The invention provides a high-dielectric low-loss ceramic composition as well as a preparation method and application thereof, and relates to the technical field of functional ceramic materials, the high-dielectric low-loss ceramic composition comprises a perovskite type compound serving as a main component and an auxiliary component; wherein the perovskite type compound contains a Ba element and a Ti element, and the auxiliary components comprise a first auxiliary component containing an Mg element, a second auxiliary component containing an Nb element, a third auxiliary component containing an Mn element, a fourth auxiliary component containing a rare earth element R, and a fifth auxiliary component containing SiO2. According to the present invention, the ratio of the main components to the auxiliary components is subjected to design optimization, the ratio of the Nb element in the second auxiliary component to the Mn element in the third auxiliary component is adjusted, and the material preparation process parameters are subjected to optimization control, such that the dielectric constant and the temperature stability of the dielectric ceramic material are improved, and the dielectric loss is reduced.

The invention relates to the technical field of transformer substation monitoring, and discloses a power supply and distribution safety monitoring method and system for a transformer substation. The method comprises the following steps: acquiring various data in a transformer substation, and performing time synchronization calibration on the three types of data; dividing a power supply and distribution operation mode into a steady-state mode, a transient mode and an overload mode based on the calibrated data, extracting a harmonic distortion rate, a dielectric loss angle tangent value and a vibration spectrum entropy value of a current waveform in each mode, and generating an operation characteristic matrix; detecting an operation mode switching event, and calculating a characteristic offset between modes; decomposing a degradation characteristic component in the operation characteristic matrix according to a matching degree between an insulation aging stage and current dielectric loss data in a historical fault case library; coupling compensation correction is performed on the degradation characteristic component in combination with the cross influence relationship between the electrical parameters and the mechanical parameters of the equipment; and reversely tracing the abnormal signal source equipment node along the topological structure of the power supply and distribution network based on the corrected degradation characteristic component, and outputting an equipment maintenance sequence.

The invention relates to the technical field of high polymer materials, and discloses a preparation method of high-dielectric-constant epoxy resin. The method comprises the following steps: (1) carrying out copolymerization reaction on bisphenol A epoxy resin and polytetrafluoroethylene at 80-100 DEG C for 2-3 hours; (2) adding a dicyandiamide curing agent into the reaction product obtained in the step (1), and carrying out gradient heating for curing; and (3) adding surface-modified barium titanate nanoparticles into the product obtained in the step (2), performing ultrasonic treatment, performing casting molding, and performing annealing treatment. According to the method, through molecular level design, the dielectric constant is remarkably improved while the excellent mechanical property of the epoxy resin is maintained, the dielectric loss (tan delta) and the thermal stability are optimized, and a high-performance base material is provided for electronic devices.

Provided are a film having a plane A consisting of a composition A and a plane B consisting of a composition B as two imaginary planes perpendicular to a thickness direction, in which a content of at least one component A contained in the composition A is decreased from the plane A toward the plane B, a content of at least one component B contained in the composition B is decreased from the plane B toward the plane A, and a dielectric loss tangent is 0.010 or less, and an application thereof.

The invention discloses a composite material polypropylene film and a preparation method thereof, and belongs to the technical field of polymer modification and polymer films. The preparation method of the composite material polypropylene film comprises the following steps: blending 5-10 wt% of maleic anhydride grafted polypropylene (PP-g-MAH), 5-20 wt% of a cycloolefin copolymer or a cyclic block copolymer and 75-90 wt% of isotactic polypropylene, granulating, carrying out melt extrusion at 240-260 DEG C, and carrying out tape casting at 80-95 DEG C to form a sheet; preheating the sheet at the temperature of 145-170 DEG C, synchronously stretching at the temperature of 150-175 DEG C, carrying out heat setting at the temperature of 160-175 DEG C, and cooling; the composite material polypropylene film is prepared through the steps of extrusion, traction, corona treatment, rolling and the like. The composite material polypropylene film not only has good heat resistance and good dielectric strength at a high temperature, but also has a relatively high dielectric constant and relatively low dielectric loss, and is suitable for a film capacitor.

The invention relates to the technical field of preparation of alumina ceramic materials, in particular to an alumina-based porcelain insulator porcelain body and a preparation method thereof. The alumina-based porcelain insulator porcelain body is prepared from interface repair type alumina and a sintering aid, the mass ratio of the interface repair type aluminum oxide to the sintering aid is 100: (5-10); the sintering aid is at least one of zirconium oxide, rare earth oxide, calcium oxide, magnesium oxide, silicon dioxide and manganese dioxide; the interface repair type aluminum oxide is interface metal atom repair type aluminum oxide, the interface metal atom repair type aluminum oxide comprises carrier aluminum oxide and metal atoms anchored at defect points of the carrier aluminum oxide in a monatomic form, and the metal atoms at least comprise Al. The alumina-based porcelain insulator porcelain body has the advantages of small dielectric constant and low dielectric loss, and meets the electrical performance requirements of extra-high voltage power transmission on insulators.

The invention discloses an electromagnetic wave absorbing material CoFe2O4 / ZnO-RGO with a ternary heterostructure as well as a preparation method and application of the electromagnetic wave absorbing material CoFe2O4 / ZnO-RGO, and belongs to the technical field of electromagnetic wave absorption. According to the material, a novel heterostructure with a multi-scale interface and a three-dimensional conductive network is constructed by compounding magnetic loss type CoFe2O4, dielectric loss type ZnO nanorods and resistance loss type RGO. Wherein the ZnO nanorod not only serves as a dielectric loss body, but also effectively enhances the structural anisotropy and the interface polarization effect of the material, and cooperates with the magnetic loss of CoFe2O4 and the resistance loss of RGO to jointly optimize impedance matching and improve the electromagnetic attenuation capability, so that the material shows excellent wave-absorbing performance under various thickness and even ultrathin conditions. The material source is wide, the cost is low, the preparation process is green, simple and convenient, the material is suitable for large-scale production, and an effective material solution is provided for electromagnetic wave absorption application in the national defense and civil fields.

A system, for measuring a dielectric property of a medium, includes: a resonator; an oscillator electrically coupled to the resonator and configured to generate an electrical signal representing an oscillation of the oscillator when the resonator is disposed in a vicinity of the medium; and measuring circuitry that receives the electrical signal. The measuring circuitry determines, from the electrical signal, at least one of a resonance frequency of the resonator and a quality factor of the resonator. The measuring circuitry determines, from the at least one of the resonance frequency and the quality factor, the dielectric property of the medium.

The invention discloses a multi-fusion-based cable state analysis method and device, terminal equipment and a storage medium, and belongs to the technical field of cable fault diagnosis, and the method comprises the steps: obtaining cable operation time sequence data; wherein the cable operation time sequence data comprises a cable partial discharge time sequence signal, cable dielectric loss time sequence data, cable circulation time sequence data, cable temperature time sequence data, environment temperature time sequence data and cable load current time sequence data; updating a fusion weight vector of the DSFF module according to the cable operation time sequence data; fusing the cable operation feature data according to the updated fusion weight vector to obtain fusion feature data; and predicting the cable state according to the fusion. Due to the fact that the cable operation time sequence data obtained in real time comprises the data related to the cable operation condition and the data related to the environment condition, the problem that the prior art is difficult to adapt to changes of the cable operation condition and the environment condition can be solved.

The invention provides a laser chip and a preparation method thereof. The laser chip comprises a light emitting region and an electric absorption modulation region. The electric absorption modulation area comprises a substrate, an active layer, a waveguide layer and a modulation electrode. The waveguide layer comprises a ridge structure, a first ridge groove and a second ridge groove, wherein the first ridge groove and the second ridge groove are located on two sides of the ridge structure. A first filling medium is arranged in the first ridge groove, and a second filling medium is arranged in the second ridge groove. The first filling medium and the second filling medium are both low-dielectric-constant media. One end of the modulation electrode is arranged on the surface of the ridge structure, and the other end is arranged on the surface of the first filling medium, namely the first filling medium is arranged between the modulation electrode and the laser chip. In the invention, when the first ridge groove and the second ridge groove are respectively filled with the low dielectric constant medium, the parasitic capacitance introduced when the modulation electrode covers along the two sides of the ridge structure can be reduced, and the dielectric loss is reduced, so that the influence of parasitic parameters on the modulation bandwidth of the laser chip is reduced, and the modulation bandwidth of the laser chip is improved.

The invention provides an LTCC raw material belt with a high thermal expansion coefficient, an LTCC substrate and a preparation method of the LTCC substrate, the LTCC raw material belt with a smooth surface and a uniform thickness is obtained through tape casting by adjusting the proportion of silicon dioxide ceramic powder, MgTiO3 ceramic, SrTiO3 ceramic, Li2MgSiO4 ceramic, BCBS, ZABS and LASP microcrystalline glass powder, the LTCC raw material belt is sintered in a nitrogen furnace at 880-940 DEG C for 1-3 h, and the LTCC raw material belt can be co-fired with low-cost copper electrode slurry to be flat and tightly attached to the low-cost copper electrode slurry. The LTCC substrate with the thermal expansion coefficient larger than 11 ppm / DEG C is prepared, under the test frequency of 5 GHz, the dielectric constant of the LTCC substrate ranges from 5.1 to 6.1, the dielectric loss ranges from 0.0025 to 0.004, the bending strength ranges from 170 MPa to 230 MPa, the thermal expansion coefficient at the temperature ranging from 30 DEG C to 400 DEG C ranges from 11.0 ppm / DEG C to 13.0 ppm / DEG C, and acid resistance is good.

The invention belongs to the technical field of cable insulation material aging detection, and relates to a cable aging degree judgment method based on an impedance spectrum and a related device. The method comprises the steps of obtaining a reflection coefficient curve based on an impedance spectrum curve; obtaining a reflection coefficient real part curve based on the reflection coefficient curve, and extracting a resonant frequency corresponding to a resonant point of the reflection coefficient real part curve; calculating a relative dielectric constant real part of an insulating medium of the cable to be measured under different resonant frequencies; outputting an attenuation constant curve based on the reflection coefficient curve and a cable reflection coefficient amplitude calculation model; extracting a plurality of attenuation constant values of the attenuation constant curve on the resonant frequency; substituting the attenuation constant value and the relative dielectric constant real part into a dielectric loss angle tangent value calculation model to obtain a dielectric loss angle tangent value of the to-be-measured cable under the resonant frequency; and carrying out aging degree judgment based on the dielectric loss angle tangent value. The problem that an existing method is long in time consumption or cannot acquire full-band dielectric information of a cable insulating material is solved.

The invention belongs to the field of wave-absorbing materials, and particularly relates to three-dimensional oriented porous aerogel loaded with yttrium-cobalt nanoparticles as well as a preparation method and application of the three-dimensional oriented porous aerogel. According to the invention, electromagnetic waves are forced to repeatedly refract and scatter through the three-dimensional honeycomb-shaped directional pore channels to have a synergistic effect with multiple heterogeneous interfaces (carbon / Co, carbon / Y2O3 and Co / Y2O3), so that the material synchronously enhances interface polarization, dipole polarization and magnetic-dielectric loss, and efficient attenuation of the electromagnetic waves is realized; by forming an intermediate ZIF-67, highly uniform dispersion of cobalt on a molecular scale is realized, and a subsequent in-situ carbonization process is combined, so that highly dispersed and tightly embedded Co nanoparticles are successfully formed in a chitosan derived carbon skeleton, the interface bonding strength is remarkably improved, and agglomeration is inhibited; according to the process, biomass chitosan is used as a carbon source, and the process has the advantages of low filling, high performance and industrial compatibility. The aerogel-based wave-absorbing material disclosed by the invention has important application value in the fields of communication, aerospace and military protection.

The invention discloses a measurement and evaluation method and system for double analysis of the aging state of a cable, and belongs to the technical field of nondestructive testing of the insulation state of electrical equipment, and the method comprises the steps: obtaining a broadband dielectric spectrum of a corresponding aging sample in any aging period, and constructing low-frequency dielectric loss data related to a plurality of aging samples; obtaining group data of a standard measurement sample corresponding to any aging sample, and constructing oxidation data about a plurality of standard measurement samples; acquiring a dielectric spectrum space charge distribution diagram based on the low-frequency dielectric loss data, and acquiring an oxidation product concentration thermodynamic diagram based on the oxidation data; obtaining an aging grading result based on the low-frequency dielectric loss data and the oxidation data; and outputting a three-dimensional aging measurement evaluation report based on the dielectric spectrum space charge distribution diagram, the oxidation product concentration thermodynamic diagram and the aging grading result. According to the measurement and evaluation method and system for double analysis of the aging state of the cable, accurate quantification of the aging degree is achieved by synchronously analyzing the dielectric response and the chemical structure change.

The application provides a hetero-composite wave-absorbing material based on attapulgite, a preparation method and application thereof. The wave-absorbing material is prepared by acid activation and high-frequency ultrasonic stirring to disperse attapulgite in a deionized water system to form an attapulgite emulsion, and the well-dispersed attapulgite fibers are uniformly coated with a carbon layer on the surface through hydrothermal stirring and high-temperature carbonization; then, a flower-like NiCo2O4 is grown in situ on the carbon-coated attapulgite to construct a hetero-interface, the carbon-coated attapulgite is used as a dielectric loss material, the flower-like NiCo2O4 is used as a magnetic loss material, through hetero-structure design, the carbon layer can inhibit the skin effect caused by the cross-linked flower-like NiCo2O4, so as to amplify the magnetic response behavior of the NiCo2O4; the hetero-interface formed between the two can significantly enhance the interface polarization, realize impedance matching, significantly improve the microwave absorption performance, and overcome the defects of impedance mismatch and structure design existing in the prior art magnetic-dielectric synergistic wave-absorbing material.

This disclosure provides a circuit board and an electronic device. In addition to a PCB, the circuit board may further include an FPC assembled on the PCB. In addition, a line between different components assembled on the PCB includes a line in the PCB, and further includes a line in the FPC. Because a quantity of core boards in the FPC is generally far less than a quantity of core boards in the PCB, selecting a core board with a dielectric loss less than that of the core board in the PCB for the FPC helps reduce a transmission loss of a high-speed signal in the circuit board, and helps reduce costs of the circuit board. This disclosure further provides an electronic device. Selecting, for the electronic device, the circuit board provided in this disclosure helps improve cost competitiveness of the electronic device in a high-speed high-density scenario.

The invention belongs to the technical field of electronic materials, and discloses a high-power and low-loss LiZn microwave ferrite material, the raw materials comprise main materials and a dopant, the main materials comprise Li2CO3, ZnO, MnCO3, CuO, NiO and Fe2O3; the doping agent is prepared from Bi2O3, CaCO3 and Co2O3. The preparation method comprises the following steps: carrying out primary ball milling and pre-sintering on the main material to obtain pre-sintered powder; adding a doping agent into the pre-sintered powder, and carrying out secondary ball milling; adding an organic adhesive into the secondary ball-milled material for granulation, and pressing into a blank; and sintering the blank to obtain the high-power and low-loss LiZn microwave ferrite material. Through a specific formula and a preparation process, uniform components and grain refinement can be ensured, and the microwave ferrite material with high Curie temperature, low ferromagnetic resonance line width, low dielectric loss and high spin wave line width is finally prepared.

The invention discloses a low-dielectric insulation fixing adhesive and a preparation method thereof, and belongs to the technical field of fixing adhesives. The raw materials comprise, by weight, 25-40 parts of an epoxy resin matrix, 5-10 parts of a modified silane coupling agent, 15-30 parts of a low dielectric filler, 8-15 parts of a curing agent, 3-8 parts of a toughening agent, 2-5 parts of a diluent, and 0.5-2 parts of an antioxidant; the low dielectric filler is a composite filler of hollow glass beads and boron nitride, the mass ratio of the hollow glass beads to the boron nitride is (2-3): 1, and the modified silane coupling agent is a gamma-aminopropyltriethoxysilane grafted maleic anhydride modified product; according to the invention, the dielectric constant and the dielectric loss of the adhesive can be reduced, and the insulating property, the bonding strength and the compatibility with a base material can be improved at the same time.

The invention discloses a state evaluation system of a metal oxide resistor disc for a lightning arrester, relates to the technical field of electrical performance testing, and solves the technical problems that the specific influence degree of environmental factors on insulation resistance is difficult to accurately quantify, and meanwhile, the influence of various factors such as environmental conditions and operation conditions on the performance of the resistor disc cannot be comprehensively considered. By establishing a correlation model, combining the insulation resistance with environmental parameters, fully considering the influence of environmental factors on the insulation performance of the resistor disc, and by establishing the correlation model, the change rule of the insulation resistance can be analyzed more accurately, and reasonable performance change caused by external conditions is considered, so that the insulation performance of the resistor disc is improved. And the performance degradation of the resistor disc can be reflected more objectively in the subsequent comparison with actual detection data. Aging factors are calculated for each region, and the comprehensive health index of the resistor disc in each region is analyzed in combination with the relative deterioration degree coefficient of the insulation resistor, the relative deterioration degree coefficient of the resistive current and the dielectric loss coefficient.

The invention discloses a high-bending-resistance and low-dielectric-loss LTCC substrate preparation method and an LTCC substrate, and the method comprises the steps: mixing inorganic powder, an organic system and a solvent through ball milling, dissolving and stirring, and preparing a green ceramic chip through a tape casting technology; carrying out lamination, warm isostatic pressing, cutting, glue discharging and sintering on the green ceramic chip to obtain the LTCC substrate; the inorganic powder comprises sodium borosilicate glass, aluminum oxide and mullite whiskers. According to the invention, the sodium borosilicate glass is used as a glass phase, the mullite whisker and the alumina powder are used as ceramic phases, and the excellent mechanical properties and extremely low dielectric loss of the mullite whisker are utilized to modify the sodium borosilicate glass-alumina composite material. The problems that an existing sodium borosilicate glass-aluminum oxide LTCC composite material is low in bending strength and high in dielectric loss are solved.