103 results about "Impedance spectrum" patented technology

This invention belongs to the field of fuel cell health status estimation technology, and specifically provides a method for estimating the health status of proton exchange membrane fuel cells based on EIS prediction. The method includes the following steps: S1: Collecting proton exchange membrane fuel cell operating data and impedance spectrum data; S2: Preprocessing the operating data; S3: Establishing an EIS prediction model based on a time-series neural network; S4: Verifying the effectiveness of the impedance spectrum; S5: Decomposing the effective impedance spectrum using the DRT method; S6: Extracting polarization resistance characteristics corresponding to different polarization processes based on the relaxation time distribution function; S7: Establishing a mapping model between polarization resistance characteristics and health status; S8: Online health status estimation. This invention solves the problems of high difficulty in obtaining electrochemical impedance spectroscopy data and high testing costs in practical applications, improving the engineering application feasibility of this method in online or quasi-online health status monitoring of proton exchange membrane fuel cells.

The application provides a detection system for interface peeling defects of a steel shell inner wall and concrete, which comprises a detection device, and the detection device comprises a signal generator, a signal amplifier, a plurality of piezoelectric material sheet assemblies, a signal acquisition assembly and a data analysis processor which are electrically connected in sequence; the plurality of piezoelectric material sheet assemblies are attached to the outer wall of the steel shell at intervals to form an electromechanical coupling system. The piezoelectric material sheet is arranged on the outer wall of the steel shell of the steel shell concrete component as a driver and a sensor at the same time, the electromechanical coupling impedance spectrum of the piezoelectric material is measured in a self-generating and self-receiving mode, the abnormal value of the electromechanical coupling impedance spectrum is analyzed, the RMSD of the electromechanical coupling impedance spectrum of the measuring point and the reference measuring point is calculated, the sensor position corresponding to the abnormal signal is screened out, and thus the accurate positioning and range estimation of the interface peeling defects are realized.

This application discloses a portable online electrochemical impedance spectroscopy measurement system and method for lithium-ion batteries, relating to the field of lithium-ion battery technology. The system includes: a power supply system for powering a power transmission system and an online measurement system, connected in parallel with a charger connected to the battery pack to achieve synchronous charging and impedance measurement; a power transmission system for converting direct current into a step function current, which is superimposed on the DC charging current and injected into the battery pack as an excitation signal; a control system for adjusting the frequency of the step function current using pulse width modulation technology; a measurement circuit module for acquiring the current and voltage signals of the battery pack; and a data analysis module for processing the time-domain signal using wavelet transform to calculate the electrochemical impedance spectrum. This application achieves low-cost, portable online measurement, enabling monitoring of the battery impedance spectrum during charging and providing support for safety early warning.

In a battery monitoring circuit, a current path provides a stimulus current to flow through a battery in multiple time windows including a first time window and second time window. Stimulus circuitry generates a signal, including information for a waveform, to control the current path, thereby changing the stimulus current, and sets a stimulus frequency of the waveform to a first value in the first time window, and to a second value in the second time window. In each time window, the sampling circuitry performs operations including: measuring a voltage of the battery at a sampling frequency, higher than the stimulus frequency, to obtain voltage values; measuring a controllable current (including the stimulus current) synchronously with the measuring of the voltage to obtain current values; and generating EIS data based on voltage and current values. The sampling circuitry provides the EIS data to a controller to perform an EIS analysis.

The application provides a method for detecting the quality of a hot plate of a plasma deposition device. The hot plate is arranged in a shell, the shell is grounded, and the hot plate has a metal line arranged inside. The metal line is part of a radio frequency line of the plasma deposition device. The method comprises: constructing a first measurement loop, the first measurement loop comprising a measurement line and a first measured line, wherein the first measured line comprises the metal line and the shell, the metal line and the shell form a first plate capacitor, the measurement line is used to output voltage signals of different frequencies and feedback impedance spectra at the different frequencies; measuring a first impedance spectrum of the first plate capacitor by using the measurement line; and determining whether the metal line of the hot plate is normal according to the first impedance spectrum.

This invention provides a method and system for reconstructing the full-band electrochemical impedance spectroscopy (EIS) of lithium-ion batteries. The method includes: performing distributed relaxation time (DRT) analysis on each group of battery EIS samples to obtain DRT spectra; aligning the DRT spectra on the logarithmic time constant axis and performing ensemble statistics, selecting peaks and / or valleys that stably appear under multiple operating conditions based on statistical stability, and mapping them to obtain a set of conditionally invariant characteristic frequencies; selecting characteristic frequency points that satisfy the sampling budget from the set of conditionally invariant characteristic frequencies, and performing sparse EIS measurements on the target battery at these characteristic frequency points to obtain sparse complex impedance inputs; generating a full-band complex impedance sequence based on the sparse complex impedance inputs using an autoregressive reconstruction model; and performing battery state estimation and fault diagnosis based on the full-band complex impedance sequence. This invention significantly improves the continuity of the spectral shape and the generalization ability across operating conditions under sparse sampling conditions, while reducing the full-spectrum testing time and sampling burden.

An active oxygen concentration control method and an active oxygen concentration control system using the control method are suitable for an electrochemical performance test using an electrode, and the control method comprises the following steps: collecting current electrochemical impedance spectroscopy data corresponding to a current test solution; determining a cut-off frequency according to the current electrochemical impedance spectroscopy data; dividing the current electrochemical impedance spectroscopy data into a concentration characteristic area with the frequency lower than the cut-off frequency and an electrode characteristic area with the frequency higher than the cut-off frequency; obtaining the current active oxygen concentration according to the current electrochemical impedance spectroscopy data in the concentration characteristic region; generating a control parameter at least according to a difference value between the current active oxygen concentration and a preset active oxygen concentration; and adding a concentration adjusting solution for adjusting the active oxygen concentration into the current test solution according to the control parameters, so that the active oxygen concentration in the current test solution reaches the preset active oxygen concentration.

This application provides an electrochemical impedance spectrum measurement method, system, and apparatus, and a readable storage medium. The method includes: inputting an excitation signal used for measuring EIS to a battery in an electric apparatus, acquiring a current value sequence and a voltage value sequence of the battery during a process of inputting the excitation signal to the battery, and determining the electrochemical impedance spectrum of the battery based on the current value sequence and the voltage value sequence. This method does not require configuration of a separate detection apparatus for batteries, which can reduce the EIS measurement cost while maintaining operational simplicity, making it highly practical for actual applications.

This application provides a method for detecting the quality of a hot plate in a plasma deposition apparatus. The hot plate is disposed within a housing, which is grounded. The hot plate contains metal wiring, which is part of the radio frequency (RF) circuitry of the plasma deposition apparatus. The method includes: constructing a first measurement circuit, which includes a measurement circuit and a first circuit under test, wherein the first circuit under test includes the metal wiring and the housing, the metal wiring and the housing forming a first parallel-plate capacitor; the measurement circuit outputs voltage signals at different frequencies and feeds back impedance spectra at the different frequencies; measuring the first impedance spectrum of the first parallel-plate capacitor using the measurement circuit; and determining whether the metal wiring of the hot plate is normal based on the first impedance spectrum.

The application discloses a copper-embedded multilayer board defect detection method and system based on eddy current thermal imaging and impedance spectrum fusion, relates to the technical field of multilayer board defect detection, and comprises the following steps: applying a high-frequency alternating pulse magnetic field to a copper-embedded multilayer board to be detected; continuously collecting thermal field cooling sequence images after pulse excitation, then extracting thermal diffusion coefficients of copper-embedded regions a and thermal field isotheral line distribution characteristics; using test probes of an automatic machine to contact copper-embedded blocks and corresponding network test points on the copper-embedded multilayer board to be detected, injecting a wideband sweep signal, obtaining impedance spectrum and extracting characteristic parameters; and a , thermal field isotheral line asymmetry, Z LF , R HF and Δ θ are constructed into a multi-dimensional feature vector, input into a fusion judgment model, and a judgment result of the copper-embedded multilayer board defect is output according to a preset multiple threshold. The application realizes non-destructive defect detection, and the micro-crack detection rate is about 97%, and the copper-embedded offset and interlayer short-circuit detection rate is 100%.

The application discloses a method for passivating arsenic pollution of tailings by modified biochar loaded nano zero-valent iron, and the method comprises the following steps: collecting wide-frequency electrochemical impedance spectrum data and passivation layer thickness data in real time through an integrated micro three-electrode system, establishing an initial passivation layer resistance value benchmark, and extracting current passivation layer resistance value and capacitance value in real time to calculate characteristic resonance frequency and minimum breakdown voltage; when the current passivation layer resistance value exceeds the preset multiple of the benchmark value, the fluctuation amplitude of the characteristic resonance frequency is less than a preset fluctuation threshold value, and the passivation layer thickness is in a preset interval, a sinusoidal alternating voltage is applied at the characteristic resonance frequency, a conductive channel is formed in the passivation layer by dielectric breakdown, and then the channel is stabilized by a direct-current reduction pulse, so that in-situ activation of the passivation layer and periodic recovery of material activity are realized.

The present application belongs to the technical field of fuel cell health state estimation, and in particular to a proton exchange membrane fuel cell health state estimation method based on EIS prediction. The method comprises the following steps: S1: collecting proton exchange membrane fuel cell operation data and impedance spectrum data; S2: preprocessing the operation data; S3: establishing an EIS prediction model based on a time series neural network; S4: verifying the effectiveness of the impedance spectrum; S5: decomposing the effective impedance spectrum by using a DRT method; S6: extracting the polarization resistance characteristics corresponding to different polarization processes according to the relaxation time distribution function; S7: establishing a mapping model between the polarization resistance characteristics and the health state; and S8: online health state estimation. The present application solves the problems of great difficulty in obtaining and high cost in testing of electrochemical impedance spectroscopy in practical application, and improves the engineering application feasibility of the method in online or quasi-online health state monitoring of proton exchange membrane fuel cells.

This invention provides a method for intelligent monitoring and early warning of water droplet impact in substations during rainy weather, relating to the field of intelligent operation and maintenance and condition monitoring of substations. The method includes: acquiring dual-optical-path video streams; constructing a cross-spectral neural radiation field network; using joint high-dimensional features as input to output volume density and radiation color vectors; calculating the equivalent water film thickness from these two vectors to generate an equivalent water film thickness distribution field; mapping this field to a three-dimensional model, subdividing the mesh according to the thickness gradient modulus, and solving for the electric field to obtain the electric field distortion tensor and calibrate the high-discharge-risk critical region; generating a Lagrange particle set, solving the dynamic equations through smooth particle hydrodynamics, and simulating the water film evolution to obtain the probability of conductive water bridge connection; inputting the distribution field, distortion tensor, and connection probability into a multi-modal impedance reconstructor to generate an electrochemical impedance spectrum to obtain the dynamic insulation margin attenuation rate; and triggering an early warning based on the determined conditions. This invention significantly improves the timeliness and accuracy of early warning for external insulation faults during rainy weather.

This application discloses a variable current charging method for lithium batteries, relating to the field of electrochemical testing. The method includes assembling a half-cell of the lithium battery under test; determining the intrinsic kinetic parameters of the half-cell under each preset state of charge by performing in-situ electrochemical impedance spectroscopy, and plotting the relationship curves between the intrinsic kinetic parameters and the state of charge; dividing the preset state of charge intervals in the relationship curves to obtain high and low kinetic windows; determining a variable current charging strategy, which includes: charging with a reference rate current within the low kinetic window, and charging with a current rate higher than the reference rate within the high kinetic window; and regulating the variable current charging of the lithium battery under test according to the variable current charging strategy. This application can significantly shorten the charging time while improving the lifespan and safety of lithium batteries.

The application discloses a lithium ion battery temperature estimation method and system based on electrochemical impedance spectroscopy. The method first performs electrochemical impedance spectroscopy testing on the same type of lithium ion battery under different states of charge, different charge and discharge cycle numbers, and different temperature conditions to obtain electrochemical impedance spectroscopy data of the battery. Based on electrochemical impedance spectroscopy analysis, a characteristic frequency with low coupling degree to the state of charge and the charge and discharge cycle number and sensitive to temperature is selected, and corresponding characteristic impedance parameters are extracted. Combined with correlation analysis, electrochemical impedance spectroscopy characteristic variables suitable for temperature estimation are determined. The global optimization of hyperparameters of the extreme gradient boosting algorithm is performed by using the Canthon optimization algorithm, and a Canthon optimization-extreme gradient boosting temperature estimation model is trained. The battery electrochemical impedance spectroscopy characteristics are input into the model, and the temperature estimation result of the lithium ion battery is output. The method is suitable for electric vehicles, energy storage systems, portable electronic devices, and the like.

This invention provides a comprehensive evaluation method for the mid-frequency performance of a filter field grounding system, belonging to the field of power grid equipment technology. The invention extracts the resonant frequency distribution by inputting a wideband impedance spectrum into an artificial intelligence frequency domain response identification model based on a coarse spatiotemporal attention mechanism. It then dynamically adjusts the spatial receptive field parameters according to the resonant frequency offset function. A three-dimensional electromagnetic field simulation model is established based on soil frequency domain parameters, and the ground potential and current density distribution are calculated using the radial basis function collocation method and the fast multipole algorithm. The entropy value of current distribution uniformity and the Gini coefficient are calculated to identify current concentration areas and assess local overheating risk. Finally, the analytic hierarchy process (AHP) is used to dynamically weight and comprehensively score indicators such as impedance peak value, resonant frequency, ground potential gradient, current uniformity, and overheating risk. This invention solves the technical problem of inaccurate performance evaluation of filter field grounding systems under mid-frequency impulse conditions.

This invention discloses an EIS detection system and method for an energy storage system, including an excitation source, a target battery cell, a first sampling circuit, and a second sampling circuit. The excitation source sends the same current signal to both the first and second sampling circuits. The first sampling circuit charges and discharges the target battery cell according to the current signal from the excitation source, providing a first excitation current to the target battery cell, and calculates a first electrochemical impedance spectroscopy (EIS) of the target battery cell based on the first excitation current. The second sampling circuit detects a second excitation current flowing through the target battery cell and calculates a second EIS of the target battery cell based on the second excitation current. During the operation of the energy storage system, even if one sampling path has noise interference, device drift, or local measurement errors, the invention can still provide auxiliary judgment criteria through another detection path, improving the stability and reliability of the EIS detection results.

The present application relates to the technical field of electrolysis analysis, and particularly relates to an electrolysis analysis method and system for visualizing bubble behavior and cooperatively representing impedance spectrum. The method comprises the following steps: during electrolysis operation, simultaneously starting electrochemical impedance spectrum test and visual observation on the surface of an electrode; obtaining data of electrochemical parameters changing with time in a first time period, and data of bubble behavior changing with time in a total time period, and obtaining data of bubble behavior changing with time in the first time period by intercepting data in a time period corresponding to the first time period from the data of bubble behavior changing with time in the total time period; and then performing correlation analysis on the bubble behavior and the electrochemical parameters. The present application simultaneously performs EIS test and visual experiment, and after time alignment, correlation analysis on the bubble behavior and the electrochemical parameters can be performed, so that the inherent mechanism of the bubble affecting electrolysis is deeply analyzed, the accurate induction factor of electrolysis performance improvement or attenuation is obtained, and operation parameter optimization guidance is provided.

The application discloses an equivalent method and system for modeling impedance of an electrolytic cell, and the method comprises the following steps: applying operating current or operating voltage to the electrolytic cell, and setting measurement parameters of an electrochemical impedance spectrum scanning device; applying an alternating excitation signal to the electrolytic cell through the electrochemical impedance spectrum scanning device based on the measurement parameters, and collecting voltage signal data and current signal data of the electrolytic cell under the alternating excitation signal; extracting frequency domain data of the impedance of the electrolytic cell based on the voltage signal data and the current signal data, and calculating impedance data; performing curve fitting on the impedance data by using a first-order or multi-order equivalent circuit model, obtaining a fitting error, and until the fitting error under the current order satisfies a preset error range, finally obtaining an equivalent circuit model; and simulating the electrolytic cell based on the equivalent circuit model. The model generated by the application only contains conventional circuit elements, and can be directly realized in simulation software such as Matlab and PSIM.

The application belongs to the technical field of new energy vehicle electrical detection and health diagnosis, and discloses a new energy vehicle wire harness aging state online evaluation method based on impedance spectrum analysis. When the target wire harness loop is turned on, a diagnosis excitation signal is injected, and the voltage and current responses of the excitation end and the other end measurement port, the switch state, the wire harness temperature, the loop current and the state of charge signal are synchronously collected. According to the switch state, the transient shielding interval is generated, and the effective sampling points are extracted. The input impedance spectrum and the transmission impedance spectrum are calculated, and the segmented mapping is carried out in combination with the wire harness topology parameters and the segmented propagation time delay parameters. Then, the working condition normalization is carried out based on the working condition reference library, and the segmented aging residual characteristics are obtained. The degradation evaluation model is input, and the segmented aging index, the aging grade and the evaluation confidence are output.

The application relates to a kind of measurement methods of proton exchange membrane fuel cell membrane resistance, specifically: hydrogen and nitrogen are respectively introduced into the anode and cathode of proton exchange membrane fuel cell;Different AC voltage disturbances are applied to proton exchange membrane fuel cell multiple times, voltage and current signal acquisition device collects the voltage and current response signals of proton exchange membrane fuel cell under different AC voltage disturbances, and the electrochemical impedance spectrum of proton exchange membrane fuel cell is obtained;The impedance spectrum is fitted by equivalent circuit, and the resistivity of proton exchange membrane fuel cell membrane resistance is calculated.Compared with prior art, the application has the advantages of not damaging the integrity of proton exchange fuel cell, not affecting the subsequent use of the measured proton exchange membrane fuel cell after resistance measurement, and obtaining the resistance value of proton exchange membrane in proton exchange membrane fuel cell under different temperature and humidity working conditions.

This invention discloses a low-cost method and system for generating laboratory life test data for lithium batteries. The method involves collecting complete life test data from two identical lithium batteries under two extreme laboratory life test conditions. A weighted average of the measured capacity decay curves of the two lithium batteries over the life test time is used to obtain a generated capacity decay curve. Each data point on each generated capacity decay curve is used as the starting point of the corresponding laboratory discharge curve, and the inflection point corresponding to each data point is predicted. The starting point and inflection point are combined to predict each complete laboratory discharge curve. Based on the predicted discharge curves, the corresponding laboratory charging curve, electrochemical impedance spectroscopy, and relaxation voltage curve are further predicted. This invention also discloses a system for implementing the above method. This invention uses weighted averaging to generate capacity decay curves and predict laboratory data, offering advantages such as simplicity, low cost, diverse data types, and strong controllability.

The application discloses a safety measurement method, device and equipment of a multiphase flow pipeline and a medium, relates to the technical field of oil exploitation, and comprises the following steps: applying an alternating excitation signal to different electrode systems arranged on a target pipeline to obtain first electric impedance spectrum data and second electric impedance spectrum data of the target pipeline in a multiphase flow state. The first electric impedance spectrum data is converted into a complex dielectric constant, and a relaxation frequency is determined from the complex dielectric constant; according to the relationship between the relaxation frequency and the particle size, the crystal particle size is determined. According to the crystal particle size and the erosion time, the erosion loss is determined. The equivalent circuit model matched with the second electric impedance spectrum data is fitted to determine the corrosion characteristics. Based on the electric impedance spectrum technology, the accurate measurement of the particle size and the erosion corrosion of two scenes is realized, the method has the characteristics of simple operation, non-invasiveness and high measurement precision, and the safety transportation of the two-phase flow pipeline is ensured.

The present application relates to a distributed power rich area cable insulation partial aging online positioning method and system, the positioning method comprising: establishing a cable distributed parameter model; superimposing f 1±1kHz and f 2±1kHz near wideband signals, the system continuously collects outlet three-phase voltage and current during operation and obtains amplitude-frequency characteristics through Fourier analysis, and the amplitude-frequency characteristics are divided by the amplitude of each phase voltage and current at each frequency point to obtain the wideband impedance spectrum of each phase; the second series resonance frequency measured in the current operating state f 2 is substituted into the cable insulation partial aging distance formula to obtain the cable insulation partial aging distance. The positioning system comprises a first calculation module, a second calculation module and a positioning module; the first calculation module determines the mathematical model of the power station back-end cable and power grid system impedance; the second calculation module obtains the impedance formula of the mathematical model of the power station back-end cable and power grid system impedance after partial aging; and the positioning module determines the position of the partial aging defect of the measured cable. The present application can obtain accurate positioning of partial aging.

This invention relates to the field of sodium-ion battery management technology and discloses a joint estimation method for the internal temperature and health status of sodium-ion batteries based on impedance spectroscopy at a few frequency points. The method collects battery voltage, current, surface temperature, coarse SOC estimate, and impedance data at candidate frequency points; calculates complex impedance characteristics and local frequency slopes; calculates temperature utility and health utility based on the statistical relationship between frequency point characteristics and temperature, SOC, and SOH; calculates gating probabilities by combining frequency point costs, and selects a small number of target frequencies; inputs the target frequency point characteristics, coarse SOC estimate, and surface temperature into a joint estimation model, which includes a temperature branch and a health branch, extracting mid-to-high frequency temperature characteristics and low-frequency aging characteristics to achieve decoupled estimation of temperature and SOH; and outputs internal temperature, SOH, and diagnostic confidence. This invention requires only a small number of frequency points to operate online, reducing the time overhead of a complete frequency sweep, and is suitable for online status estimation and fault early warning of sodium-ion battery cells, modules, and energy storage systems.

A method of isolating and quantifying contributions to the impedance of a power unit comprises: obtaining an impedance spectrum from the power unit; fitting a pure capacitance term to remove capacitiv

The application discloses a kind of cable health state evaluation method and system based on single-end open circuit impedance spectrum, belong to nondestructive testing and impedance spectrum analysis technical field.This method only needs to carry out frequency sweep test at one end of cable and keep open circuit at the end, after obtaining wideband input impedance spectrum, extract real part data and identify resonance extreme point;The upper and lower envelope lines are constructed by extreme point interpolation, and the high-frequency characteristic impedance and attenuation constant of the full frequency band are derived;Further, the distributed parameters of the cable are calculated by combining the phase constant.By comparing the characteristics of the distributed parameters, the health status of the cable can be accurately evaluated, and the physical mechanism can effectively distinguish between thermal aging and moisture damage.The application eliminates the cumbersome of double-end cooperation test, does not need to intercept samples, greatly saves the test time, has wide applicability and strong anti-interference ability.

A device may perform impedance spectroscopy on a component under test. The frequency response analyzer circuitry may be coupled to the component under test outside of a current loop supplying an operational current to the component under test. The frequency response analyzer circuitry may drive a variable impedance circuit to generate an oscillating current component within the current loop. The frequency response analyzer circuitry may monitor a frequency response of the component under test to the oscillating current component.

The application provides an evaluation method for prolonging the durability life of a concrete structure pole by a surface corrosion-resistant coating, and relates to the technical field of concrete structure durability evaluation, and comprises the following steps: a plurality of monitoring points are arranged on the surface of a target pole concrete, and coating thickness, adhesion and electrochemical impedance spectrum characteristic values are collected; equivalent retardation coefficients of the coating at each point under a combined environment of chloride ions and carbon dioxide are calculated, and are expanded into time-varying equivalent retardation coefficients; the coefficients are input into a reference model as attenuation factors, chloride ion diffusion coefficient time-varying functions and carbonation rate coefficients are corrected, and local life attenuation curves of each point are generated; the running time corresponding to the first reaching of a durability limit state threshold is taken as a whole durability life prediction value; the value is compared with a theoretical failure time under a non-coating condition, and a prolonging life value of the corrosion-resistant coating on the durability life of the pole concrete structure is calculated, thereby providing a scientific basis for quantitative evaluation of the coating protection effect.

The application discloses a full-cell DCR growth tracing, symmetric cell preparation and electrolyte optimization method, and belongs to the technical field of lithium ion batteries, and comprises the following steps: S1, preparing a symmetric soft package cell system: selecting a single-face positive plate or a single-face negative plate from a non-cycled or cycled cell after formation, assembling a positive or negative symmetric cell, and respectively injecting a basic electrolyte and a to-be-tested electrolyte to form two symmetric cells; S2, DCR growth tracing analysis: performing a constant-current discharge test on the symmetric cell to obtain DCR growth rate data, and determining whether the DCR growth of the full cell is mainly from the positive side or the negative side; and combining electrochemical impedance spectroscopy (EIS) and relaxation time distribution (DRT) methods, further distinguishing whether the DCR growth is from SEI film impedance growth or charge transfer impedance growth. The method eliminates the crosstalk effect between the positive and negative electrodes, realizes accurate diagnosis of the DCR growth source, and provides a key basis for targeted design and efficient development of electrolytes.