171 results about "Wave impedance" patented technology

The invention provides a deep and far sea wind power plant area lightning dynamic parameter inversion method and device, and relates to the technical field of lightning protection, and the method comprises the steps: building a fan return stroke model based on current reflection caused by the wave impedance discontinuity of a fan top, a return stroke channel and a fan bottom grounding position, obtaining an initial propagation model of the electromagnetic field along the sea-land mixed path by combining the surface equivalent impedance of the sea surface and the land of the observation point zone; correcting the initial propagation model through electromagnetic field influence parameters to obtain a target propagation model; inputting a radiation source signal received by an array into the target propagation model for waveform time sequence inversion processing to obtain a corresponding time reversal signal; the time reversal signals in different directions are superposed and focused to obtain the peak azimuth, and the three-dimensional positioning of the lightning radiation source is carried out in combination with the positioning result of the double stations, so that the lightning development spatial-temporal distribution law is determined, and the measurement precision of the lightning leader development speed is remarkably improved.

An electronic device may include signal transmission circuitry having a signal path and a signal source that transmits a signal on the signal path. First and second signal couplers may be coupled to the signal path. Control circuitry may use the first signal coupler to measure the signal at a first reference plane and may use the second signal coupler to concurrently measure the signal at a second reference plane. The signal measurements may include power wave, forward wave, reverse wave, impedance, and / or delivered power measurements. Terminations in the signal couplers may be adjusted to dynamically shift the reference planes. The first and second signal couplers may be formed from first and third metallization layers on a stacked dielectric substrate, where the signal path is formed from a second metallization layer. Additional signal couplers may be coupled to the signal path for concurrently measuring additional reference planes.

The invention discloses a diffracted wave impedance inversion method based on full wave field information, and the method comprises the steps: carrying out the diffracted wave separation of full wave field original seismic data, and obtaining reflected wave seismic data and diffracted wave seismic data; converting an interval velocity body obtained by processing the full-wave-field original seismic data to obtain an interval velocity low-frequency impedance body; determining a corresponding relation between the full-wave-field original seismic data and the synthetic seismic data in-phase axes, and extracting a comprehensive wavelet; under the constraint of the logging data and the interval velocity low-frequency impedance body, based on the comprehensive wavelet, a post-stack impedance inversion method is adopted to perform inversion on the full-wave-field original seismic data, and a full-wave-field absolute impedance body is obtained; under the constraint of a layer velocity low-frequency impedance body, based on the comprehensive wavelet, a post-stack impedance inversion method is adopted to invert the reflected wave seismic data, and a reflected wave relative impedance body is obtained; and removing the reflected wave relative impedance body from the full wave field absolute impedance body to obtain the diffracted wave absolute impedance body. According to the method, the wave impedance inversion precision of the heterogeneous reservoir can be improved.

The invention discloses a diffracted wave-based heterogeneous body prediction method, electronic equipment, a storage medium and a diffracted wave-based heterogeneous body prediction device. The method comprises the following steps: acquiring a diffracted wave three-dimensional seismic data volume, a horizon of a target interval and a comprehensive wavelet based on a full-wave-field three-dimensional seismic data volume; constructing a longitudinal wave velocity and density conversion relation based on the logging longitudinal wave velocity and the corresponding density, and further constructing a longitudinal wave velocity and longitudinal wave impedance conversion relation to convert the interval velocity of the full-wave-field three-dimensional seismic data volume into interval velocity low-frequency impedance; constructing a diffracted wave impedance inversion objective function based on the longitudinal wave diffraction coefficient and the comprehensive wavelet, and taking the interval velocity low-frequency impedance body as the background impedance of the inversion objective function; and solving the diffracted wave impedance inversion objective function based on an optimization algorithm, carrying out diffracted wave impedance inversion, and obtaining diffracted wave impedance to carry out heterogeneous body prediction. Quantitative prediction of the heterogeneous body is realized through the diffracted wave three-dimensional seismic data body, and the impedance inversion precision of the heterogeneous reservoir is improved.

The application provides a kind of ice constant temperature dynamic mechanical property testing device, belongs to ice detection technical field, including launch subassembly, impact lever, incident support, incident lever, sample support, transmission support, transmission lever, data acquisition module and data processing module, the end face of impact lever towards incident lever is equipped with several spaced convex structures, the end face of incident lever towards impact lever is equipped with shaping piece, shaping piece is used to extend the rising time of incident stress wave that incident lever transmits to ice sample, the end face of incident lever towards ice sample is equipped with wave modulation module, wave modulation module is used to realize the wave impedance continuous gradient matching of incident stress wave from incident lever to ice sample, data processing module corrects the data collected by data acquisition module to obtain final incident wave strain and final transmission wave strain, and calculates the strain rate, stress and strain of ice sample.The application scheme improves the accuracy of ice constant temperature dynamic mechanical property test results.

The embodiment of the application provides a power amplifier circuit, a radio frequency front end module and a communication device, relates to the technical field of electronics, and is used for improving the saturation power and saturation efficiency of the power amplifier circuit. The power amplifier circuit adopts an impedance matching network architecture of series connection of a capacitor and an inductor in at least one branch (which can be a main power amplifier branch or a peak power amplifier branch). Under the architecture, the fundamental wave impedance and the harmonic impedance of the branch are both adjusted by the series connection capacitor and inductor network. However, since the capacitance of the capacitor and / or the inductance of the inductor can be changed, the fundamental wave impedance is fixed, and the second harmonic impedance is changed. That is, when the second harmonic impedance is adjusted in a wideband range, the fundamental wave impedance can not be affected. Based on this, by reasonably selecting the capacitance of the capacitor or the inductance of the inductor, the fundamental wave impedance and the second harmonic impedance in the branch can meet the requirements respectively, so that the power amplifier circuit has relatively optimal saturation power and saturation efficiency.

The present application relates to a kind of seismic wave impedance diffusion inversion method and device, its essence is a kind of from well site to surrounding diffusion layered structure and attribute inversion method.Core is to use well logging curve to carry out layering etc., then carry out well position inversion, simultaneously, to make the result obtained by well logging interpretation and actual seismic record difference minimum, need to be appropriately disturbed by the square wave type calibration layering curve obtained from well logging interpretation, generate hundreds of reflection coefficient curves, to generate synthetic seismic record, find the synthetic record with actual seismic record difference minimum, the horizon etc. corresponding to this best synthetic record is regarded as the best seed solution and diffuses to all around, during diffusion process, by adding time window or horizon to constrain vertical propagation interval, to obtain the inversion optimum value of entire data set, specific flow as shown in Figure 1.The present application improves the precision of thin layer boundary delineation, and has higher potential for thin layer resolution.

This invention relates to a wave impedance inversion method, comprising the following steps: Step 1, collecting post-stack seismic data, sonic logging curves, density logging curves, lithology-representing curves, and reservoir interpretation results within the work area; Step 2, calculating wave impedance curves based on sonic logging and density logging curves; Step 3, assigning values ​​to various types of reservoirs to obtain formation identification codes; and reconstructing the wave impedance curves using the formation identification codes to obtain reconstructed wave impedance curves; Step 4, performing intersection analysis using the lithology-representing curves and the reconstructed wave impedance curves; Step 5, performing wave impedance inversion on the post-stack seismic data using the reconstructed wave impedance curves. This invention can directly identify effective energy storage with high accuracy.

The invention provides a discontinuous pulse signal frequency acquisition system and method, and the system comprises an attenuation unit, a filtering unit, an impedance matching unit, a first comparator, a second comparator and a main control unit, and the attenuation unit is used for reducing the amplitude value of an input pulse signal; the filtering unit is used for filtering the signal after the amplitude value is reduced; the main control unit is connected with the first comparator and the second comparator. According to the invention, the discontinuous pulse signal is attenuated and subjected to filtering impedance matching and then is input into the first comparator and the second comparator at the same time, the main control module triggers the first comparator to count when detecting the rising edge output by the second comparator, and the first comparator calculates the period of two continuous square waves, so that the frequency of the discontinuous pulse signal is obtained; effective and rapid acquisition of discontinuous pulse signal frequency is realized.

The invention discloses a thick sand body thin dessert quantitative description method based on seismic forward iteration driving. The method comprises the steps of determining single well lithofacies division, a reservoir type and a dessert reservoir type; constructing a lithofacies and dessert seismic inversion attribute probability body; constructing a three-dimensional lithofacies model by taking the lithofacies probability body as a trend constraint, and constructing a double-constraint dessert body three-dimensional model by taking the model as phase control and the dessert probability body as a constraint; a wave impedance body is constructed according to a reservoir type statistical wave impedance mean value, a near-angle superposition seismic body is selected as a test seismic body, and seismic wavelets are preferably selected; taking the wave impedance body, the test seismic body and the seismic wavelets as input, generating a forward modeling seismic data body through convolution operation, and calculating a three-dimensional correlation coefficient between the forward modeling seismic data body and the original seismic body; and when the three-dimensional correlation coefficient is greater than a set threshold value, outputting a double-constraint dessert body three-dimensional model, otherwise, correcting geologic model parameters, updating the model, carrying out iterative calculation again until conditions are met, and finally depicting thin dessert distribution in the thick sand body according to the conditions.

This invention discloses a clamping method for lightning overvoltage on overhead lines and a combined lightning protection and vibration prevention device. The method includes the following steps: based on the propagation characteristics of lightning waves in a medium, a local impedance abrupt change point is set on the overhead line to alter the propagation process of the lightning wave; wherein, the local lightning wave impedance at the local impedance abrupt change point is less than the overhead line impedance; when the lightning wave reaches the impedance abrupt change point, the voltage wave undergoes negative reflection while the current wave undergoes positive reflection, and the electric field energy of the lightning wave is converted into magnetic field energy, thereby achieving the clamping of the lightning overvoltage. This invention actively clamps lightning overvoltage through impedance transformation and achieves integrated lightning protection and vibration prevention, completely eliminating the dependence of traditional protection on low grounding resistance, effectively reducing the lightning tripping rate while eliminating spatial conflicts and mutual interference between devices.

The invention discloses a water-rich stratum TBM tunnel front surrounding rock water content and seepage water pressure combined detection method, and aims to solve the problem that related measurement is difficult in the prior art. Two sets of drill holes are formed in the symmetrical positions of the three o'clock and the nine o'clock of the two waists of a tunnel behind a TBM shield through a jumbolter, a pair of electromagnetic wave transmitting antennas and a pair of electromagnetic wave receiving antennas are installed in the drill holes respectively, the boundary position of a water-containing body in front of the TBM is detected through wave impedance, and the water content is calculated through three-dimensional imaging; near a water-rich area detected by electromagnetic waves, an advanced drilling machine is used for forming two drill holes in the 1st-half position and the twelve-half position of the top of a TBM shield, and a vibrating wire data acquisition instrument is used for monitoring the seepage water pressure of the surrounding rock of the tunnel. The water content of the surrounding rock in front of the TBM tunnel can be detected, the seepage water pressure can also be detected, and a decision basis is provided for water burst and mud burst in TBM construction.

The application discloses a kind of shale oil reservoir's attenuation-elastic-electricity combined modeling and parameter prediction method, belong to geophysical exploration and oil and gas reservoir evaluation technical field.First, obtain mineral components, pore structure and elastic-attenuation-electricity full-dimensional experimental data through core experiment, determine attenuation and resistivity as high sensitivity parameter after sensitivity analysis;Again, based on Hashin-Shtrikman boundary, differential equivalent medium theory, triple-pore medium wave propagation equation, construct the acoustic and electrical rock physics model of completely consistent micro-pore structure;Finally, establish longitudinal wave impedance-attenuation coefficient-resistivity three-dimensional joint rock physics chart, after multi-band correction, simultaneously quantitative prediction reservoir porosity, shale content and fracture porosity.The application breaks through the limitation of conventional acoustic-electricity combined model, significantly reduces the multi-solution of reservoir parameter prediction, and is suitable for fine evaluation of various shale oil tight reservoirs.

The application provides an inversion method for describing the connectivity of the internal reservoir of a faulted karst body. The method uses seismic attributes reflecting the outline of the faulted karst body, the holes and cracks in the faulted karst body, establishes a comprehensive low-frequency model reflecting the carbonate bedrock, the faulted karst body, and the crack and hole system in the faulted karst body, uses the model to perform post-stack constrained sparse pulse inversion, obtains a longitudinal wave impedance data body of the underground, and uses the longitudinal wave impedance data to give a longitudinal wave impedance threshold value of the reservoir, and describe the connectivity of the internal reservoir of the faulted karst body in space.

The invention belongs to the field of power system protection and control, and particularly provides a fault positioning method and device for a cable mixed line and a medium for fault positioning of the cable mixed line. According to the invention, by introducing the wave impedance discontinuity characteristic and the traveling wave speed difference characteristic, the complex structure problem in the hybrid line is specially processed, and the fault positioning precision is significantly improved. The traveling wave attenuation characteristics under different frequencies are analyzed to extract the traveling wave energy of the key frequency component, and the traveling wave energy is fused into the LSTM-CNN network, so that the accuracy of fault positioning is further improved. Shallow layer and deep layer features of the signals are extracted through the CNN layer, the relation between the fault position and the line structure can be reflected more comprehensively, and fault positioning robustness is improved.

The invention relates to a full-band high-precision seismic inversion method, which belongs to the technical field of reservoir prediction in oil and gas field exploration, and comprises the following steps: firstly, carrying out low and medium frequency filtering interpolation on logging data to establish a wave impedance initial model, and then carrying out wave impedance inversion based on seismic data; and carrying out waveform clustering on residual seismic disturbance obtained by subtracting actual seismic data from forward modeling data of the wave impedance inversion result, carrying out transverse high-frequency inversion on a logging high-frequency component according to a waveform clustering result, and finally fusing a low and medium frequency inversion result and a high-frequency inversion result to obtain a full-band high-precision inversion result. According to the method, the high-frequency component inversion is driven by the residual seismic disturbance obtained by subtracting the actual seismic data from the forward modeling data of the low and medium frequency inversion result, so that the difficulty of inaccurate high-frequency information inversion of the existing inversion method is effectively overcome, the full-band high-precision inversion driven by the seismic data is realized, the resolution and accuracy of the seismic inversion are greatly improved, and the method is suitable for large-scale popularization and application. And accurate identification of the thin reservoir in oil and gas field exploration and development is facilitated.

The present application relates to the technical field of engineering blasting optimization, in particular to a dynamic optimization design method based on engineering blasting parameters, comprising: collecting stratum geological parameters such as rock hardness profile and rock mass fracture distribution of blasting site and blasting vibration three-direction velocity time history monitoring data, carrying out time-frequency joint analysis on time history record to extract dispersion curve and energy attenuation envelope, and constructing a digital rock mass structure model capable of calculating blasting stress wave propagation path. The vibration characteristic data is used as boundary condition to carry out numerical simulation to obtain simulated vibration velocity field, according to the difference between simulated data and measured data, combining with rock mass wave impedance distribution, the intelligent optimization algorithm is used to iteratively optimize the charge structure parameters and initiation time sequence scheme, and the optimized blast hole charge quantity, section and initiation delay are output. The method can improve the accuracy of blasting vibration propagation simulation, reduce the deviation between simulated and measured vibration velocity fields, and make the blasting parameter design more suitable for the actual geological environment of the engineering site.

The embodiment of the application provides a thin reservoir identification method and device, and belongs to the field of geophysical exploration. The identification method comprises the following steps: acquiring well logging data of all sample oil wells in a target area, processing the well logging data to obtain well control processing parameters; the well control processing parameters comprise a Tar factor of amplitude recovery, a Q factor of absorption attenuation and anisotropic velocity; based on the well control processing parameters, a three-dimensional seismic data body is acquired; seismic data of the target area is acquired; based on the three-dimensional seismic data body and the seismic data, a wave impedance model of the target area is constructed; a model optimization iteration algorithm is used to correct the wave impedance model until the fitting degree of seismic records obtained by forward modeling of the wave impedance model and the well logging data reaches a predetermined fitting degree; wherein, the inversion result of the wave impedance model is a thin reservoir identification result. The application aims to improve the identification accuracy of thin reservoirs.

This invention provides a method, apparatus, device, and medium for predicting formation pore pressure. The method includes: confirming one-dimensional wave impedance data of a single well based on well logging data of a target area; establishing a first relationship model between P-wave velocity and wave impedance based on the one-dimensional wave impedance data of the single well; confirming a first wave impedance data volume using a genetic inversion algorithm based on the one-dimensional wave impedance data of the single well and seismic data; confirming a first wave velocity data volume based on the first wave impedance data volume and the first relationship model; and confirming a formation pore pressure data volume based on the first wave velocity data volume, and predicting formation pore pressure based on the formation pore pressure data volume. This invention predicts formation pore pressure based on the logging characteristics of drilled wells and combined with high-resolution seismic data, taking into account various factors such as regional tectonic background and sedimentary characteristics, thus improving the accuracy of pore pressure prediction for undrilled formations.

The application discloses a gas saturation calculation method, an electronic device and a medium. The method can comprise: determining a plurality of sample depths and corresponding gas saturations; calculating a complex wave impedance corresponding to each sample depth; establishing a fitting formula about the complex wave impedance and the gas saturation according to the gas saturation and the complex wave impedance corresponding to each sample depth; calculating the complex wave impedance of a target position, and then calculating the gas saturation corresponding to the target position through the fitting formula. The application quantitatively calculates the gas saturation of a pore space while considering the change of a skeleton mineral composition in the longitudinal direction through the complex wave impedance.

The application discloses a set smoothing time-lapse seismic difference inversion method based on probability mode conversion. The method comprises the following steps: acquiring time-lapse seismic data and logging data; constructing a linear forward model between difference seismic data and relative wave impedance difference parameters based on a convolution model; extracting a logging label reflecting real underground wave impedance difference, calculating a cumulative probability distribution and a functional inverse function thereof based on a probability integral transformation, and constructing a probability mode conversion operator; in a set smoothing framework, updating a model set of a multivariate Gaussian distribution by using a Kalman gain, and mapping the updated model to a model set conforming to a logging real distribution through the conversion operator; and iteratively performing the above process to obtain a posterior inversion result of the relative wave impedance difference. The application can directly invert a relative difference parameter, and effectively improves the inversion precision of a time-lapse seismic difference parameter with a non-Gaussian distribution characteristic and the reliability of reservoir dynamic characterization.

The invention discloses a traveling wave / transient state quantity protection method and system for an electric power system and electrical equipment, and terminal equipment. A bypass attenuation effect of a bus stray distribution capacitor on a fault traveling wave / high-frequency transient quantity or a hindering effect of reactance of electrical equipment on the fault traveling wave / high-frequency transient quantity, a refraction and reflection effect of the fault traveling wave / high-frequency transient quantity at a wave impedance discontinuous point and a shunting effect at a branch, and a hindering effect of a wave trapper on a specific frequency band are utilized; the internal relation between the difference value and the average value of the observed values at the two different monitoring points is utilized, the relative gradient or gradient or kurtosis or relative kurtosis or gradient or relative gradient is utilized to calibrate the initial effective action period of the fault traveling wave / transient quantity, and traveling wave / transient quantity protection is constructed. According to the method, the initial effective action period of the fault transient quantity, the effective action period of the fault traveling wave head and the arrival time of the fault traveling wave head are accurately calibrated, and the problem that the arrival time of the traveling wave head cannot be accurately calibrated by traditional transient / traveling wave protection is solved.

A method for predicting electromagnetic performance of a three-dimensional structure unit cell configuration and an impedance matching design method, the prediction method comprising: experimentally measuring the basic electromagnetic parameters of the lossy material used in the three-dimensional structure unit cell configuration, assuming that the lossy material is an isotropic medium, and calculating the equivalent electromagnetic parameters of each layer of the configuration according to the duty cycle; calculating the fractal dimension of the whole three-dimensional structure unit cell configuration and determining the duty cycle and thickness of each layer of the three-dimensional structure unit cell configuration; constructing a structure resonance effect factor by using the basic electromagnetic parameters of the lossy material, the fractal dimension and the duty cycle, and then correcting the impedance gradient correction coefficient; and establishing a model equation of the macroscopic equivalent physical characteristic parameters of the structure interface, and calculating the interface wave impedance and surface reflectivity of the three-dimensional structure unit cell configuration by using the model equation. The theoretical and simulation calculation absorption peak frequency points are basically consistent, the macroscopic equivalent calculation method can accurately predict the absorption peak frequency point position, and the effectiveness of the calculation method is illustrated.

This invention discloses a design and manufacturing method for a uniform cross-section explosive load simulator based on gradient elastic metamaterials, relating to the field of impact loading. Addressing the problems of high cost per use and the susceptibility of variable cross-section elastic rods to local buckling instability under high-speed impact leading to waveform distortion in existing simulators, this invention, while maintaining the macroscopic uniform cross-section shape of the simulator, derives the ideal wave impedance gradient required to achieve the target explosive load based on the one-dimensional elastic wave propagation inverse design theory; establishes the mapping relationship between the relative density of a three-period minimal surface (TPMS) metamaterial unit cell and its equivalent mechanical parameters, and inversely solves the spatial relative density distribution function; extracts the waveform through dynamic impact finite element simulation, and introduces an impedance gradient correction factor to perform nonlinear iterative correction of the density function, obtaining a final three-dimensional metamaterial geometric model that accurately matches the waveform, and uses a flexible polymer material for additive manufacturing. This invention achieves the purely elastic, non-destructive, and reusable simulator, perfectly adapting to the stable firing of light gas cannons, and exhibiting excellent anti-instability capability and waveform fidelity under strong dynamic loads.

The invention discloses an offshore wind power flexible direct output control method based on transmitting end V / F network construction and a receiving end virtual synchronous machine. A transmitting end converter adopts dynamic V / F network construction control to generate a network construction angle, and electromagnetic wave propagation time delay and wave impedance are calculated based on distribution parameter characteristics of a long-distance direct current transmission line; phase compensation is performed on the network construction angle, and voltage compensation is performed on the output reference voltage, so that phase deviation and voltage attenuation caused by long-distance transmission can be offset; the receiving-end converter is controlled by a variable-parameter virtual synchronous machine, the inertia coefficient of the receiving-end converter is adjusted in real time according to double feedback of the amplitude and the change rate of the frequency deviation of an alternating-current power grid connected with the receiving-end converter, and the damping coefficient is dynamically corrected through a proportional-integral-differential feedback mechanism; the transmitting-end converter dynamically adjusts the network construction frequency through frequency-DC voltage coordination control, and the fan of the offshore wind power plant adjusts the active power output according to the DC voltage change rate, thereby achieving the cooperative operation of the system.

The invention discloses a coal measure tight sandstone thin reservoir prediction method based on seismic frequency division configuration inversion, and relates to the technical field of oil-gas exploration and development, and the method comprises the steps: 1, collecting logging curve data, and carrying out the standardization processing; 2, performing wavelet transform on the standardized data to extract a signal, and reconstructing the extracted signal through wavelet inverse transform to obtain a pseudo-wave impedance curve; 3, constructing a frequency division configuration model according to the simulated wave impedance curve and the collected seismic data; 4, according to the frequency division configuration model, random inversion is carried out through a Markov chain Monte Carlo random algorithm, and reservoir parameters are obtained. According to the method, phase control-logging-seismic data are combined, and frequency division configuration inversion is fused into the lithology and fluid sensitive reconstruction curve to realize accurate prediction of the coal measure tight sandstone thin reservoir.

The invention relates to the technical field of oil and gas exploration, and discloses a hole structure parameter inversion method and device, electronic equipment and a medium. The method comprises the following steps: acquiring key rock physical parameters; processing logging data of the typical well, and calculating a hole structure parameter curve of the typical well; mathematical optimization is carried out, and coefficients of hole structure parameter constraint conditions are determined; pre-stack elastic parameter inversion is used to acquire a longitudinal wave impedance data body and a transverse wave impedance data body of the work area to be inverted; based on hole structure parameter constraint conditions, establishing a nonlinear mapping relation of longitudinal wave impedance and transverse wave impedance about the porosity, and solving a porosity inversion result by using a golden section algorithm; and calculating inversion results of the volume modulus hole structure parameters and the shear modulus hole structure parameters. According to the technical scheme, density is not used, inversion of hole structure parameters is achieved only through longitudinal wave impedance and transverse wave impedance, and input data are more stable; the use conditions of hole structure parameter inversion are broadened, and the stability and precision of hole structure parameter inversion are improved.

The invention discloses a grid-connected inverter power grid voltage transient disturbance self-adaptive impedance matching method, relates to the technical field of new energy power generation, and effectively avoids a frequency spectrum aliasing phenomenon and ensures the accuracy of data by collecting power grid voltage and inverter output current in real time and performing accurate anti-aliasing filtering processing. Subsequently, a windowing FFT analysis technology is utilized to accurately extract fundamental wave and specific sub-harmonic components, and a reliable data basis is provided for subsequent impedance calculation and harmonic compensation. The power grid impedance is calculated in real time through the recursive least square method, and the virtual inductance at the inverter side is dynamically adjusted, so that effective compensation for the fundamental wave impedance mismatch is realized, and the stability of the system is remarkably improved. Finally, generation of PWM signals is optimized by adopting a model prediction control technology, rapid tracking of a compensated current reference value is realized, and transient response time is further reduced.

The application discloses a kind of λ / 4 stepped impedance transformation method and system.Therein, the method includes: in the impedance mismatching of partial discharge ultrahigh frequency load impedance and the characteristic impedance of partial discharge ultrahigh frequency measurement system, access λ / 4 stepped impedance transformation two-port network, the load impedance is wave impedance;According to characteristic impedance Z 0, wave impedance Z L And the characteristic impedance of two-section λ / 4 transmission line Z 1, Z 2, determine partial voltage reflection coefficient;According to the partial voltage reflection coefficient, determine total voltage reflection coefficient;According to the total voltage reflection coefficient, broaden the working frequency band of λ / 4 stepped impedance transformer.Therefore, break through the limitation of direct matching, by the progressive stepped impedance matching mode of sensor element, realize partial discharge ultrahigh frequency signal sensor element and subsequent radio frequency processing circuit good matching, thereby reduce the partial discharge ultrahigh frequency signal attenuation caused by impedance mismatching.

This invention discloses a Marchenko multiple suppression method for tracking wave impedance interfaces, belonging to the field of seismic data processing technology. The method includes the following steps: S1, obtaining wave impedance inversion results across the entire depth domain based on surface observation seismic data and the background velocity field; S2, extracting the location information of strong wave impedance interfaces and identifying several key locations between these interfaces; S3, using a Bezier curve smoothing method to obtain the spatial location of the focal point that maximizes the penetration of the strong wave impedance interface; S4, determining the ascending and descending Green's functions for the spatial location of the focal point; S5, predicting interlayer multiples using seismic interferometry; and S6, obtaining the seismic shot gather for suppressing interlayer multiples through adaptive matched filtering. This invention does not require a precise velocity model, relying only on a macroscopic velocity model, and can obtain deep-domain strong wave impedance geological information, accurately predicting and suppressing interlayer multiples by combining wave impedance information.