157 results about "Dielectric loss factor" patented technology

The invention relates to the technical field of high-frequency signal transmission, and discloses a high-frequency signal transmission optimization method for a radio frequency coaxial connector. The method comprises the following steps: acquiring an original electromagnetic parameter sequence when a high-frequency signal is transmitted in a target working frequency band in real time, wherein the original electromagnetic parameter sequence comprises an impedance change value, a dielectric loss factor and a conductor skin depth measurement value; layered feature analysis is carried out on the data, features of a basic transmission layer, an interface reflection layer and a medium coupling layer are separated out, and a layered electromagnetic feature set is generated; identifying a key performance influence section according to the set, constructing a non-uniform frequency domain analysis grid, dividing a reflection sensitive area by using a fine frequency band, and dividing a transmission stable area by using a wide frequency band; performing time-frequency joint simulation based on the grid, and extracting a full-band dynamic transmission response spectrum; and combining with the material electromagnetic property database to optimize the structure parameter configuration scheme, generating an optimization instruction set, and loading the optimization instruction set to a processing control system to execute physical structure dynamic adjustment operation.

The invention relates to the technical field of power equipment monitoring, in particular to a transformer fault diagnosis method, system and device based on multi-modal deep learning and a storage medium. Obtaining the volume fraction of gas dissolved in oil of the transformer, the local discharge capacity, the sleeve dielectric loss factor, the vibration data and the infrared image data; continuous wavelet transform processing based on integrated gradient is carried out on the vibration data, and key fault frequency bands are dynamically screened to generate a time-frequency map; inputting the numeric data into a stack-type denoising auto-encoder network to extract depth features; respectively inputting the infrared image and the radio frequency map into a double-branch convolution encoder for early feature fusion, and extracting map depth features through a stack type convolution auto-encoder network; and based on the Dempster-Shafer evidence theory, carrying out conflict resolution and evidence synthesis on the fault probability distribution output by the two types of modes, and outputting a diagnosis result.

The invention relates to the technical field of transformers, in particular to a transformer component fault diagnosis method based on machine learning, which comprises the following steps: analyzing medium data acquired by a transformer component, comparing a dielectric loss factor sequence with offset characteristics, training and generating an offset time sequence characteristic set, screening abnormal time periods and aggregating key discharge characteristics, and performing fault diagnosis. And obtaining an abnormal clustering signal group, concluding a trend evolution sequence, performing layered optimization on a path structure, and outputting fault link positioning data. According to the method, various parameters such as dielectric loss, discharge, temperature rise, gas and vibration are integrated, abnormal distribution is actively screened, key node trend change is captured in real time, historical and real-time characteristics in different operation scenes are fused, and efficient analysis of complex link evolution and implicit anomalies is realized. And the fault evolution relationship among the nodes is output in a structured manner, direct application of a diagnosis result in full-link traceability and multi-node trend research and judgment is supported, and the fault diagnosis pertinence and the hidden danger recognition capability are effectively improved.

The invention provides a capacitive equipment resistive current taking-free PT signal measurement method suitable for a lightning arrester, and relates to the technical field of capacitive equipment resistive current measurement. The method comprises the following steps: deploying a non-contact electric field coupling sensing array; acquiring a multi-channel main induction signal and an equipment high-voltage side induction electric field signal; performing cascade filtering processing to obtain a filtering reference signal; dynamically correcting the phase deviation of the filtered reference signal to obtain a calibration reference signal; collecting a leakage current signal, and separating to obtain a resistive current component; and constructing a dielectric loss factor multivariable dynamic compensation model based on the deep belief network, embedding a capacitive equipment operation duration cumulative effect factor, and updating parameters in real time through an online learning algorithm to obtain a resistive current measurement result. High-precision measurement of resistive current is realized through an advanced technology, a model is established in combination with multiple environment parameters and equipment operation duration, adaptability is improved, and long-term accurate monitoring is guaranteed through online parameter updating.

The invention discloses a high-precision transformer fault detection method and system, relates to the technical field of transformer detection, is used for solving the problems of insensitive fault characterization and delayed diagnosis under a light load condition, and judges whether to enter a load judgment mechanism or not by acquiring input side access voltage information and counting low-load accumulated duration. When entering a load discrimination mechanism, detecting the start-stop behavior of a load branch and the temperature rise trend of a winding, calculating a light load index, identifying a light load state, carrying out region division on an iron core, collecting magnetic flux density data, and calculating iron loss balance characteristics aiming at iron loss deviation which is easy to occur under a light load condition; the insulation degradation coefficient is calculated by fusing the oil temperature peak value and the dielectric loss factor, and the abnormal index is generated with the iron loss balance characteristic, so that the early warning of the early hidden fault of the transformer can be realized in a light load scene in which the traditional temperature rise and current indexes are insensitive, and the operation reliability and maintenance efficiency of the transformer in a power distribution system are improved.

To provide hollow particles in which the dielectric dissipation factor is decreased, and the performance stability in high-humidity environment is improved. Hollow particles comprising a shell, which contains a resin, and a hollow portion surrounded by the shell, wherein the hollow particles have a void ratio of 50% or more; wherein the shell contains a polymer as the resin, and a content of a crosslinkable monomer unit is 60% by mass or more in 100% by mass of all monomer units of the polymer; and wherein an aqueous dispersion of the hollow particles, which is obtained by dispersing the hollow particles with a volume of 0.35 cm3 in 100 mL of deionized water, has a pH of 6.5 or more and 7.5 or less and a conductivity of 50 μS / cm or less.

The invention relates to the technical field of power equipment state monitoring, in particular to a capacitive equipment state online evaluation method based on artificial intelligence and frequency domain interpolation, which comprises the following steps: acquiring a complex frequency spectrum of an equipment signal and extracting working condition characteristics; inputting the working condition characteristics into a working condition modulation model to generate dynamic parameters for adjusting an adversarial interpolation correction model in real time; the correction model converts frequency spectrum slices into optimized frequency spectrums, so that the dielectric loss factor is accurately calculated. Afterwards, the factor and other operation parameters are combined into a multi-dimensional time sequence, the multi-dimensional time sequence is input into a health state evaluation model, an abnormal score representing the real insulation degradation state of the equipment is output, and a diagnosis data object containing a measurement result consistency score is generated. According to the invention, the artificial intelligence model is introduced, the measurement error is dynamically compensated according to the real-time working condition, intelligent diagnosis is carried out, and the accuracy and reliability of online evaluation are remarkably improved.

The invention discloses a cable accessory aging detection method based on multi-parameter fusion wavelet transform, and the method comprises the steps: building a cable accessory AC steady-state equivalent circuit model, and obtaining the current and voltage dynamic data of a target cable accessory sample at a test temperature; decomposing the signal by using wavelet transform, setting a dynamic threshold according to the wavelet coefficient amplitude difference under each scale, and separating noise from a target signal; dielectric property change data with a high signal-to-noise ratio are extracted through signal reconstruction, and the aging state of the cable accessory is analyzed in combination with a dielectric loss angle. According to the method, the problems that a traditional method is long in detection period and prone to interference are solved, the accuracy and real-time performance of cable accessory aging and degradation monitoring are remarkably improved, and electric power safety accidents can be effectively prevented.

The invention discloses a flame-retardant epoxy resin adhesive with a low dielectric constant and a low dielectric loss factor as well as a preparation method and application of the flame-retardant epoxy resin adhesive, and belongs to the technical field of electrical insulating materials. The method comprises the following steps: uniformly mixing and stirring epoxy resin and alicyclic epoxy resin to obtain an epoxy resin mixture; uniformly stirring liquid acid anhydride, a flame retardant, an epoxy active toughening agent and an accelerant to obtain an epoxy resin curing agent; and vacuumizing and uniformly stirring the epoxy resin mixture and the epoxy resin curing agent to obtain the flame-retardant epoxy resin adhesive with low dielectric constant and low dielectric loss factor. Dielectric loss of the epoxy resin mixture is reduced through polarity complementation, and molecular chain segment polarization is reduced through an alicyclic epoxy resin ring structure. And the flame retardant is dispersed into a uniform flame-retardant phase in liquid anhydride, so that the mechanical property is prevented from being reduced. A flexibilizer and anhydride are grafted to introduce a flexible chain segment, vacuum mixing is performed to eliminate an air gap, and after gradient curing, a low dielectric constant, a low dielectric loss factor and flame retardance are obtained.

The invention relates to the technical field of power supply control, and particularly discloses a control method of a high-power isolated power supply, which realizes full-life-cycle intelligent management of an isolated power supply oil paper insulation system by constructing a complete technical chain from dielectric loss factor monitoring to PDIV drift inversion and then to insulation life prediction and operation control. The insulation state on-line monitoring unit collects the key insulation performance index of the dielectric loss factor in real time, the aging degree and the performance change of the oil paper insulation medium in the operation process can be accurately reflected, and compared with a traditional off-line detection method, the real-time performance and the accuracy of monitoring are greatly improved. The operation parameters of the equipment can be dynamically adjusted according to the real-time evaluation result of the insulation state, sudden faults caused by insulation failure are effectively avoided, and the safety and reliability of operation of the equipment are remarkably improved.

The invention relates to a high-mica granite machine-made sandstone concrete quality control system. The high-mica granite machine-made sandstone concrete quality control system comprises the following steps that S1, pretreated granite aggregate is conveyed into double-cavity type microwave irradiation equipment; s2, the dielectric constant of the granite aggregate is detected through double-cavity microwave irradiation equipment, high-frequency treatment is conducted on the granite aggregate with the dielectric loss factor larger than 0.05, and low-frequency treatment is conducted on the granite aggregate with the dielectric loss factor smaller than or equal to 0.05; s3, the granite aggregate subjected to microwave treatment is conveyed into liquid nitrogen spraying equipment, microcracks are generated between mica layers through thermal shock stress, and mica interlayer stripping is triggered; and S4, the granite aggregate is recovered to the room temperature through temperature recovery equipment, and the granite aggregate is separated from mica on the granite aggregate through winnowing impurity removal equipment. The microwave-liquid nitrogen synergistic stripping technology is adopted, the content of mica in the high-mica granite is reduced, and control over the quality of the granite machine-made gravel concrete is achieved.

The present invention relates to a benzocyclobutene resin, a resin composition, and uses thereof. The benzocyclobutene resin comprises at least one structural unit A and at least one structural unit B, where structural unit A has a structure represented by Formula I and structural unit B has a structure represented by Formula II. The benzocyclobutene resin has an all-hydrocarbon structure and has a sufficiently low dielectric constant Dk and dielectric dissipation factor Df. The benzocyclobutene resin also has a high glass transition temperature, low water absorption, good heat resistance and moist heat resistance, excellent dielectric properties, high modulus, and mechanical properties. Furthermore, the benzocyclobutene resin also has good processability, fully meeting the performance requirements for resin materials in high-performance PCBs.

The invention relates to the technical field of cables, and particularly provides an RTDS-based XLPE cable aging influence analysis method and system, and the method comprises the steps: building a RTDS-based hybrid operation system simulation model; acquiring a plurality of XLPE insulation aging samples at different time; measuring the insulation resistance of each XLPE insulation aging sample, and calculating the volume resistivity; measuring the dielectric constant and the dielectric loss factor of each XLPE insulation aging sample; inputting into a simulation model, and after the simulation model operates under different working conditions, outputting cable parameters, active power, key point three-phase phasor voltage data and key point three-phase phasor current data of each insulation aging sample; obtaining the influence of cable aging on the maximum transmission power; and obtaining the imbalance influence of the cable aging on the system. The influence of XLPE cable aging on a hybrid operation system is comprehensively explored, and a key basis is provided for operation maintenance, optimization and upgrading of a power system.

The invention provides a switch cabinet solid insulating material performance detection method based on temperature detection, which comprises the following steps: constructing a gridding detection matrix on the surface of an insulating material, and collecting temperature data of each monitoring area through a passive radio frequency sensor to establish an initial temperature field data set; adopting a deep learning algorithm to calculate a temperature gradient value and thermal stress distribution, and establishing a temperature-stress coupling model; calculating a dielectric loss factor and a local ionization degree based on the model, constructing a performance degradation index and establishing a degradation prediction model; combining a recurrent neural network and an attention mechanism to predict a performance evolution trajectory, and setting a multi-stage dynamic early warning threshold value; when early warning is triggered, a sampling strategy is adaptively adjusted, model parameters are optimized through real-time data, and an intelligent diagnosis report containing state evaluation, life prediction and maintenance suggestions is generated. According to the invention, accurate prediction and intelligent diagnosis of performance degradation of the solid insulating material can be realized, and the real-time performance and reliability of monitoring the insulation state of the switch cabinet are improved.

The invention discloses a high-voltage power transmission and transformation line equipment insulation aging monitoring method and system, and relates to the technical field of equipment insulation state monitoring, and the method comprises the steps: extracting voltage time-frequency features in a high-voltage time sequence data set to generate a voltage time-frequency feature matrix, and outputting a dual-channel feature pair through separating a current mode component of a current signal; calling standard parameters of the high-voltage equipment, calculating a dielectric loss factor according to the dual-channel characteristic pair, and eliminating measurement deviation through a quantum tunneling effect to obtain a corrected dielectric loss factor; the frequency response characteristic of the corrected dielectric loss factor is analyzed, the aging type is judged by identifying an offset mode, and the aging degree coefficient of the equipment is calculated to divide the state level; and generating a processing scheme based on the aging type, obtaining an execution priority according to the state level, and generating a maintenance instruction set by binding a timestamp. Through the quantum tunneling effect, the response aging is optimized in combination with the dynamic maintenance decision, and closed-loop management of insulation aging from accurate monitoring to active protection is realized.

The present invention provides: a fluororesin film for a multilayer structure substrate, with which it is possible to produce, without using an adhesive, a multilayer structure substrate that has less transmission loss during high-frequency communication; a method for producing the fluororesin film for a multilayer structure substrate; a copper-clad laminate; a multilayer structure substrate; a method for producing a multilayer structure substrate; and a circuit board.　Disclosed is a fluororesin film for a multilayer structure substrate, which contains a fluororesin and an inorganic filler that is dispersed in the fluororesin, wherein the dielectric loss tangent Df is 0.0013 or less and the loss elastic modulus at a temperature of 350°C is 1.6 MPa or more. The fluororesin film for a multilayer structure substrate is used for the purpose of producing a multilayer structure substrate by bonding, without using an adhesive, a plurality of copper-clad laminates that have a two-layer structure in which a copper foil and the fluororesin film for a multilayer structure substrate are laminated.

The invention discloses an insulation detection method for cable windings of a phase modifier, and relates to the field of phase modifiers, and the method comprises the following steps: S1, sequentially embedding an A-phase cable, a B-phase cable and a C-phase cable into iron core grooves of a stator iron core to respectively form a corresponding A-phase winding, a B-phase winding and a C-phase winding, and the insulating layer of each phase cable is made of a crosslinked polyethylene material; s2, cable terminal connectors are mounted at the wire outlet end and the neutral end of each phase of winding and are grounded; s3, respectively carrying out insulation resistance detection test on each phase of winding; s4, respectively carrying out an alternating current withstand voltage test on each phase of winding; and S5, respectively carrying out dielectric loss factor detection test on each phase of winding. The device can detect the insulation performance of the cable winding of the direct-hanging phase modifier, and has the advantages of comprehensive detection and high reliability.

This invention discloses a multi-physics in-situ testing platform for aramid-synthetic ester composite insulating materials. The method includes: pre-treating an aramid substrate by drying and impregnation to obtain a composite sample; clamping the sample between test electrodes; applying a stable and controllable temperature field and an electric field to the sample sequentially or simultaneously; and measuring the dielectric constant, dielectric loss factor, and conductivity of the sample in situ under stable thermo-electric coupling conditions. The testing platform includes test electrodes for clamping the sample, a temperature control module for applying the temperature field, an electric field loading module for applying and adjusting the electric field, and a data acquisition module for in-situ data collection. By optimizing the sample pre-treatment process and the synchronous loading control of multi-physics fields, this invention achieves high-precision and highly repeatable in-situ testing of the dielectric properties of materials under actual service conditions within a wide temperature and field strength range. It is particularly suitable for evaluating the performance evolution of composite insulating materials under thermo-electric coupling.

This invention relates to a transformer body unit and an electromagnetic voltage transformer device. The transformer body unit includes an iron core element, a first coil element and a second coil element respectively housed on the lower and upper parts of the iron core element, a first shielding element and a second shielding element respectively housed on the first coil element and the second coil element, and a lower insulating element and an upper insulating element respectively housed on the first shielding element and the second shielding element. Its advantages are: by utilizing the upper and lower insulating elements, optimal electric field distribution is obtained, making the transformer device capacitive, effectively avoiding resonance between the electromagnetic voltage transformer device and circuit breaker capacitance, line-to-ground distributed capacitance, etc., ensuring the safe operation of the power grid; by using the transformer body unit, the diameter of the porcelain bushing unit can be reduced, reducing oil weight and overall weight; the upper and lower insulating elements give the product good electrical strength and insulation performance as well as a low dielectric loss factor; overcoming the disadvantages of unstable performance, poor transient performance, and small output capacity.

A bismaleimide compound of general formula (I): wherein R1 is a divalent aliphatic group and R2 is a divalent aromatic group; and a resin composition comprising the bismaleimide compound of general formula (I), having a low dielectric constant (Dk), a low dielectric loss factor (Df), and a high glass transition temperature (Tg).

Embodiments in accordance with the present invention encompass compositions containing the polymer formed from a variety of polycycloolefinic monomers at least one of which monomer contains an additional unpolymerized ethylenic bond, melamine, clay such as bentonite or montmorillonite, optionally fillers such as hexagonal boron nitride or silica, a crosslinker, a free radical initiator, a tackifier and one or more suitable additives. The compositions of this invention can be formed into a variety of three-dimensional insulating articles upon exposure to suitable high temperature, such as for example films. The objects formed from the compositions of this invention exhibit hitherto unattainable low dielectric constant and low-loss properties, fire-retardancy and very high thermal properties. The compositions of this invention are useful in various applications, including as insulating materials in millimeter wave radar antennas, among others. The films formed from the compositions of this invention exhibit a UL-94 rating of at least V-1, dielectric constant (Dk) less than 2.9 and dielectric dissipation factor (Df) of less than 0.003.

The present invention discloses a method for evaluating the dielectric loss factor of power equipment under the action of an oscillating wave high voltage, which is applied to the field of high voltage test technology. In addition to evaluating the oscillating wave voltage information in the traditional dielectric loss factor evaluation method, the oscillating wave current is evaluated. Through mathematical deduction, a mathematical expression for the relationship between the dielectric loss factor and the oscillating wave voltage and current waveform parameters is obtained; based on an algorithm combining phase-shifted fast Fourier transform and nonlinear least squares method, the oscillating wave voltage and current sequence is processed to obtain waveform parameter estimates, and then an estimated value of the dielectric loss factor is obtained. The dielectric loss factor evaluation algorithm of the present invention has good anti-noise interference capabilities, and at the same time, the dielectric loss factor estimation accuracy is high.

The present invention provides a fluorine-containing resin-based resin composition and its application. The fluorine-containing resin-based resin composition comprises a combination of a fluorine-containing resin and an inorganic filler; the mass of the fluorine-containing resin is 25-50 parts based on the total mass of the fluorine-containing resin and the inorganic filler as 100 parts; the inorganic filler comprises titanium dioxide; the average particle size of the titanium dioxide is 1-6 μm, and the maximum particle size is less than 10 μm. The fluorine-containing resin-based resin composition and the fluorine-containing resin-based dielectric sheet and metal foil-clad plate containing the same have excellent dielectric and insulating properties, a low dielectric loss factor, and high resistivity. Moreover, the fluorine-containing resin-based resin composition has good dispersibility of the components and uniformity of the glue, excellent coating properties, controllable product thickness, and good performance consistency, fully meeting the various requirements for copper-clad plate materials in the field of high-frequency and high-speed communications.

To provide a curable resin composition which gives a cured product simultaneously satisfying low dielectric characteristics (low dielectric constant and low dielectric loss tangent), good dielectric characteristics after moisture absorption, high adhesion to a copper foil, and high heat resistance.SOLUTION: A curable resin contains a structural unit represented by formula (1), at least one of a structural unit represented by formula (2) and a structural unit represented by formula (3), and a terminal (meth)acryloyl group.SELECTED DRAWING: Figure 1

The invention relates to the technical field of transformer oil treatment, in particular to an adsorption regeneration transformer oil purification system and a control method.The adsorption regeneration transformer oil purification system comprises an adsorption device, the output end of the adsorption device is fixedly connected with a transfer device through a pipeline, and the output end of the transfer device is fixedly connected with a cooling device through a pipeline; through composite adsorption and vacuum dehydration and degassing, the dielectric loss factor of oil is greatly reduced, the withstand voltage value is remarkably improved, the insulation breakdown risk of the transformer is effectively avoided, the service life of equipment is prolonged, energy waste is reduced through constant-temperature control, cooling water is recycled, consumables and water resource consumption are reduced, the operation and maintenance cost of enterprises is reduced, full-process PLC automatic control is achieved, and the production efficiency is improved. Multiple monitoring protection of vacuum, pressure, liquid level and the like is matched, frequent manual intervention is not needed, risks of pipeline pressure building, leakage and the like are avoided, the operation stability is improved, waste gas is subjected to multi-stage treatment of buffering, spraying and activated carbon adsorption, peculiar smell is avoided, up-to-standard emission is achieved, and pollution to the surrounding environment is reduced.

The invention discloses a cable connector vulcanization mold and a vulcanization method. The vulcanization method comprises the following steps: carrying out roughening pretreatment on the surface of a metal insert to form a microstructure; starting a heating system of the vulcanization mold to heat the mold core area to a preset temperature, and injecting aerial fog containing a coupling agent into the mold cavity so as to form a chemical activity interface on the surface of the mold cavity; the pretreated metal insert is positioned in a mold cavity, the rubber compound is injected into the mold cavity through a spiral feeding port in a rotary propelling mode, and meanwhile the pressure of the mold cavity is kept; applying an electric field while keeping the temperature of the mold core area, and switching to a cooling stage when the dielectric loss factor is reduced to a preset value to obtain a vulcanized product; the vulcanization product is ejected step by step by adopting a multi-stage pressure ejection mechanism, and a low-temperature cooling medium is injected into an ejection gap in the ejection process to perform local shock cooling treatment, so that a finished connector is obtained, the dielectric constant fluctuation is remarkably reduced, and the product obtains ultrahigh dimensional precision and dielectric stability.

The invention provides a composite insulating layer of a light superconducting cable and a preparation method and application of the composite insulating layer. The composite insulating layer is prepared from the following raw materials in parts by weight: 40-60 parts of fusible polytetrafluoroethylene, 30-50 parts of fluorinated ethylene propylene, 0.5-5 parts of an auxiliary agent, 1-5 parts of filler and 0.1-0.6 part of a nucleating agent. The composite insulating layer of the light superconducting cable has relatively high tensile strength, relatively low dielectric constant and dielectric loss factor, good mechanical property and high insulating strength; compared with the prior art, the composite insulation layer has the advantages of low average cell diameter and high cell density, which indicates that a uniform and fine cell structure is formed in the composite insulation layer, the overall density of the material can be effectively reduced, the insulation layer is light, and the composite insulation layer can be applied to preparation of light superconducting cables for medical equipment and realizes integrity and low loss of high-frequency signal transmission.

The invention discloses an insulating oil dielectric loss factor detection method and system, and relates to the field of oil-immersed power equipment detection.The method comprises the steps that terahertz testing is conducted on insulating oil samples of different aging degrees, and corresponding terahertz time-domain spectrums are obtained; determining a terahertz absorption spectrum; according to the terahertz absorption spectrums of the insulating oil samples with different aging degrees and the corresponding dielectric loss factor values, determining terahertz absorption spectrum characteristics based on a partial least squares regression model; establishing a terahertz dielectric loss value quantitative evaluation model based on a random forest algorithm according to the terahertz absorption spectrum characteristics of the insulating oil samples with different aging degrees and the corresponding dielectric loss factor values; and according to the terahertz absorption spectrum characteristics of the to-be-detected insulating oil, determining a corresponding dielectric loss factor value based on the trained terahertz dielectric loss value quantitative evaluation model. According to the invention, the dielectric loss factor of the insulating oil can be quickly obtained without damage, and the insulating oil can be quickly evaluated without damage.

The invention relates to an intrinsic flame-retardant low-dielectric epoxy resin. The molecular structure of the epoxy resin comprises a) a biphenyl group, and at least one of b) a polyphenylene oxide (PPO) group, c) a polyether sulfone (PES) group or d) a polyamide imide (PAI) group. The preparation method comprises the following steps: dissolving biphenyl epoxy resin in a solvent, adding a polymer with an active group, adding independently or in a certain proportion in a combined manner, fully dissolving, adding a catalyst, heating, and carrying out solution polymerization; and after the reaction is finished, supplementing the solvent to prepare the solvent type modified epoxy resin. The obtained product can improve the limit oxygen index of the epoxy resin, reduce the dielectric constant Dk and the dielectric loss factor Df, realize a greener and more environment-friendly flame-retardant target, and better adapt to the performance requirements of high-end electronic products on high-speed transmission and low loss of electric signals.

Provided is a resin sheet which withstands adsorption and transportation by a vacuum adsorption pad for transportation, has low thermal expansion, and has a relative dielectric constant (Dk) of 2.50 to 3.30 in a high frequency band of 10 GHz band or more, and a dielectric dissipation factor (Df) of 0.0020 or less in a high frequency band of 10 GHz band or more. In addition, provided are a laminate, a printed wiring board, and a semiconductor package produced using the resin sheet. The resin sheet is specifically a resin sheet including a resin component (A), and an inorganic filler (B), in which the component (A) contains an elastomer (A1) having a number-average molecular weight of 10,000 or more, a content of the component (B) is 25 to 70 volume % based on a total amount of the resin sheet, and a breaking energy is 0.1 mJ / mm3 or more.