63 results about "Electrical impedance spectroscopy" patented technology

Electroporation-based therapies (EBTs) employ high voltage pulsed electric fields (PEFs) to permeabilize tumor tissue, resulting in changes in passive electrical properties detectable using electrical impedance spectroscopy (EIS). Currently, commercial potentiostats for EIS are limited by impedance spectrum acquisition time (˜10 s); this timeframe is much larger than pulse periods used with EBTs (˜1 s). Fourier Analysis SpecTroscopy (FAST) is introduced as a methodology for monitoring tissue inter-burst impedance (diagnostic FAST) and intra-burst impedance (therapeutic FAST) during EBTs. FAST is a rapid-capture (<<1 s) technique which enables monitoring of inter-burst and intra-burst impedance during EBTs in real-time. FAST identified a frequency which delineates thermal effects from electroporation effects in measured impedance. Significance: FAST demonstrates the potential to perform EIS, in addition to intra-burst impedance spectroscopy, using existing pulse generator topologies.

The invention relates to the technical field of circuit boards, and discloses a circuit board interlayer connection detection method, device and equipment, and the method comprises the steps: carrying out the electrical characteristic parameter measurement of a multilayer flexible circuit board, and obtaining the characteristic parameter data of the circuit board; designing and arranging a multi-test-point detection structure on the multi-layer flexible circuit board, and performing signal excitation to obtain test point position information; applying a differential excitation signal, and collecting a differential response waveform between the test points to obtain a time domain reflection signal feature; impedance spectrum conversion and parameter extraction are carried out on the time domain reflection signal features, and an interlayer connection impedance distribution diagram is obtained; and establishing an interlayer connection defect characteristic model aiming at nickel-based alloy wire fracture, interface cracking and liquid metal fiber felt delamination in various bending states by utilizing the interlayer connection impedance distribution diagram, so that accurate classification of defect types and severity is realized, and interlayer connection faults and surface welding quality problems can be distinguished; and the misjudgment rate is greatly reduced.

The invention provides a ground wire monitoring method and system, and relates to the technical field of ground wire monitoring. The method comprises the following steps: acquiring a voltage signal of an injection point and a current signal of a grounding loop; preprocessing the signal to obtain a preprocessed signal; according to the preprocessed signals, impedance frequency spectrums of the grounding loop under different frequencies are obtained through calculation, and key feature parameters in the impedance frequency spectrums are extracted; environment parameters and operation state data of the power equipment are collected and fused with the key feature parameters, and fused data are obtained; adjusting a judgment threshold value or a reference baseline corresponding to the key feature parameters by using the fused data; and judging the current grounding loop state by using the adjusted judgment threshold value or reference baseline. According to the method, based on impedance spectrum analysis, electromagnetic interference is overcome through multi-stage signal processing, robust feature extraction and multi-dimensional data fusion analysis, and the effects of adapting to a dynamic baseline and distinguishing different electric leakage types are achieved.

The invention relates to the technical field of AC / DC module control, and discloses an intelligent control method and system for multi-mode switching of an AC / DC module. According to the method, a dynamic topology mapping model is constructed according to an impedance spectrum matrix, and a physical connection relation is converted into a node admittance relation network; generating an energy distribution state sequence based on the power fluctuation vector, and analyzing migration constraint conditions among different operation modes by adopting an association rule mining algorithm; when an operation mode switching instruction is detected, activating a node admittance relation network in the dynamic topology mapping model, and inputting a current energy distribution state sequence to an association rule mining algorithm; according to a real-time matching result of the node admittance relation network and the migration constraint condition, generating a switching control instruction containing an impedance adjustment gradient and a power distribution weight; and the power semiconductor execution unit transmits the switching control instruction to the AC / DC module. According to the method, multi-mode intelligent switching control of the alternating-current and direct-current module can be realized.

The invention provides a method for extracting equivalent parameters of a cavity resonant wireless power transmission system. The method comprises the following steps: S1, acquiring system input impedance spectrum data; s2, taking the input impedance spectrum data of the system as input, and utilizing a trained LSTM regression model to obtain a preliminary predicted value of an equivalent parameter of the system; s3, based on the preliminary prediction value of the equivalent parameters of the system, performing regression fitting by adopting a nonlinear fitting algorithm to obtain an accurate value of the equivalent parameters of the system; the system equivalent parameters comprise cavity internal resistance and cavity equivalent inductance of the resonant cavity and a mutual inductance value between the coil and the resonant cavity. The method has the advantages that equivalent parameters of the cavity resonant wireless power transmission system in all current mainstream modes can be effectively extracted; the NLS algorithm is prevented from convergence failure or falling into local optimum due to the fact that an initial value seriously deviates from a real value, and the fitting precision and stability are extremely high.

The invention provides a new energy station grid-connected oscillation risk assessment method and device, and relates to the field of new energy grid-connected control. The method comprises the following steps: constructing a dynamic equivalent model based on new energy station operation parameters; based on the dynamic equivalent model, obtaining impedance spectrum feature domains in different control modes; calibrating an impedance spectrum feature domain based on a semi-physical simulation platform; inputting the calibrated impedance spectrum feature domain into a grid-connected oscillation risk assessment model, and outputting oscillation damping ratio predicted values of the new energy station in different control modes based on the grid-connected oscillation risk assessment model; and constructing a self-adaptive threshold, and evaluating the grid-connected oscillation risk of the new energy station based on the magnitude relationship between the oscillation damping ratio predicted value and the self-adaptive threshold in different control modes. The method solves the problems that when different control modes are switched or external operation conditions are changed, a prediction result of a traditional method is prone to distortion, and the real oscillation risk of the new energy station is difficult to reflect accurately.

The invention belongs to the technical field of energy storage system state monitoring, and provides a lithium ion energy storage system abnormal state identification method and system based on impedance spectrum analysis, and the method comprises the steps: carrying out the decoupling of voltage response data and current response data through employing an excitation-response decoupling algorithm under a dynamic working condition, and obtaining an impedance spectrum; obtaining a voltage response component and a current response component; obtaining the total impedance spectrum of the lithium ion energy storage system under the current working condition; constructing a system-level impedance cloud picture; calculating a difference value between the current impedance spectrum and the weighted moving average baseline spectrum based on the system-level impedance cloud atlas to obtain an enhanced difference cloud atlas; and performing non-uniform segmentation and feature extraction on the enhanced difference cloud picture by using a visual Transform model oriented to electrochemical prior to obtain a multi-dimensional abnormal probability vector, and obtaining an abnormal state type of the lithium ion energy storage system based on the multi-dimensional abnormal probability vector. According to the technical scheme, the accuracy, timeliness and reliability of abnormal state recognition of the energy storage system are remarkably improved.

The invention discloses a battery SOC prediction method and system based on dynamic electrochemical impedance spectroscopy measurement in the technical field of lithium battery state prediction, and the method comprises the steps: superposing DIBS square wave signals as excitation current input on the basis of the main charging and discharging current of a battery, and collecting the voltage and current data of the battery in real time; according to the impedance spectrum, fitting a fractional order equivalent circuit model by adopting a nonlinear least square optimization method to obtain initial parameters of the fractional order equivalent circuit model; the initial parameters and voltage and current data collected in real time are input into a self-adaptive dual augmented extended Kalman filter, the main filter and the secondary filter operate cooperatively, state prediction and parameter prediction are executed alternately, and real-time synchronous prediction of SOC and fractional order equivalent circuit model parameters is achieved. The method is suitable for the SOC estimation requirement of the battery under the dynamic working condition, the working state of the battery does not need to be interrupted, and the method has good linearity, robustness and adaptivity.

The invention relates to the technical field of alarm, in particular to a hydrogen-cooled generator manhole door hydrogen leakage prevention intelligent early warning system, which comprises a signal acquisition module for applying a measurement current to a manhole door sealing ring where a hydrogen-cooled generator is located through an electrode array, obtaining an original time domain signal, calculating to obtain a frequency domain response vector, and calculating a hydrogen leakage early warning value based on the frequency domain response vector; and extracting a complex impedance real part and imaginary part combination of each frequency point to generate impedance spectrum data. The method comprises the following steps of: applying alternating-current measurement current to a manhole door sealing ring, acquiring frequency domain response vector and impedance spectrum data, extracting relaxation characteristic frequency points from an impedance spectrum, closely associating the relaxation characteristic frequency points with current state parameters such as temperature and pressure of a hydrogen-cooled generator, and establishing reference characteristic parameters of an initial state; therefore, the real-time characteristics of the sealing ring in a dynamic environment are reflected.

The invention discloses a harmonic stability evaluation method, device and equipment applied to a renewable energy power system and a medium, the method is applied to the technical field of power system harmonic, and the method comprises the steps: carrying out the impedance aggregation processing of topological structure data, and obtaining a harmonic impedance model; processing the renewable energy equipment data based on a Nyquist stability criterion to obtain a stability boundary condition of the power system; constructing a node admittance matrix based on the harmonic impedance model and the stability boundary condition; processing the node admittance matrix by using a Fourier technology to obtain impedance spectrum data, and processing the impedance spectrum data based on a modal impedance maximum value analysis method to obtain resonance modal characteristics; processing the resonance mode characteristics and the real-time operation condition to obtain a time domain verification result; and carrying out harmonic stability evaluation based on a time domain verification result. According to the method provided by the invention, the technical problem of harmonic stability evaluation distortion caused by incomplete measurement data can be solved.

The invention relates to the technical field of electrical safety monitoring, in particular to a leakage protection system for a low-voltage IT power supply system. Comprising an impedance spectrum identification unit used for constructing an original spectrum data set; calculating a system-to-ground complex impedance spectrum based on the original spectrum data set; a parallel RC equivalent circuit model is applied to decouple the real insulation resistance and the system ground capacitance based on the system ground complex impedance spectrum; the dynamic evaluation unit is used for constructing an insulation health index; calculating a system structure change factor; the trend prediction unit is used for calculating an insulation aging rate based on a time sequence formed by historical real insulation resistance data; the comprehensive risk decision-making unit is used for calculating a comprehensive risk index; and outputting a tripping signal in response to the insulation health index exceeding a preset final protection limit value. The problem of false alarm caused by the fact that a traditional protection device cannot distinguish resistive leakage current and capacitive leakage current is solved, and the protection accuracy is remarkably improved.

The present invention discloses a measurement and judgment method for orthopedic diagnosis, which belongs to the technical field of orthopedic diagnosis and treatment, comprising: collecting magnetic field signals of bone metabolism through a magnetic field sensor array, collecting electrical impedance spectroscopy data through a four-electrode method to form an original data set; filtering and denoising the magnetic field signals and correcting motion artifacts, and then fitting the electrical impedance spectroscopy data with a Cole-Cole model to extract bone density, porosity, and moisture content; calculating bone metabolic current density through a magnetic field-current inversion algorithm, combining electrical impedance characteristics and current characteristics, and generating a bone health index through a dynamic weight distribution mechanism; by combining the magnetic field-current inversion algorithm with Cole-Cole model analysis, multi-dimensional information of bone metabolic activity and bone tissue structure can be simultaneously obtained, thereby effectively overcoming the problem of insufficient information from a single physical field and significantly improving the accuracy of diagnosis.

The present invention discloses a cable length detection method, device, equipment and storage medium. The method comprises: inputting an initial excitation signal into a cable to be detected to obtain an initial impedance spectrum diagram of the cable to be detected; the impedance spectrum diagram represents the relationship between the impedance of the cable to be detected at different frequencies; determining an initial cable length and an initial cable length range according to the initial impedance spectrum diagram; the initial cable length range includes a first boundary cable length and a second boundary cable length; determining the difference between the initial cable length and the first boundary cable length and the second boundary cable length respectively to obtain a first difference and a second difference; determining a target excitation signal based on the first difference and / or the second difference to determine a target cable length of the cable to be detected based on the target excitation signal; ensuring that the difference between the target cable length and the target cable length range is within a preset error threshold, thereby greatly improving the accuracy and precision of cable length detection.

The application relates to the field of water pollution monitoring instruments and discloses a sewage monitoring method combining optical and electrochemical sensing, which comprises the following steps: acquiring an original photoelectric conversion voltage matrix and an original impedance frequency spectrum sequence of a measured medium in a sensing field; calculating a relative deviation rate of a chemical oxygen demand measurement value; acquiring a transient Doppler frequency shift distribution sequence and extracting a flow field disturbance factor when the relative deviation rate continuously exceeds a preset signal deviation threshold value; calculating a dynamic response gain; judging whether a physical response shield exists on a monitoring interface according to whether the dynamic response gain is lower than a preset mass transfer shield lower threshold value; and outputting a sensor passivation early warning signal if it is judged that the physical response shield exists. The application verifies the mass transfer effectiveness of the monitoring interface by using flow field kinetic energy fluctuation, identifies the passivation phenomenon of the physical interface of the sensor, eliminates false standard data output caused by physical degradation of the probe, and guarantees the authenticity of the monitoring data.

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.

The invention relates to the technical field of electrical measurement, and discloses an impedance spectrum-based distribution network line hidden defect online detection method and system, and the method comprises the steps: inputting a broadband current signal with the frequency point density in topological arrangement along with a line into a distribution network line; performing fast Fourier transform on the voltage response signals in the distribution network line, and synthesizing the transformed voltage response signals to obtain a real-time impedance spectrum of the distribution network line; binding impedance frequency spectrums collected under a defect-free working condition with environmental parameter labels, and collecting the bound impedance frequency spectrums into an impedance reference library of the distribution network line; matching a real-time environment parameter with the impedance frequency spectrum in the impedance reference library to obtain a reference impedance frequency spectrum of the distribution network line; and performing defect deconstruction on the frequency point deviation value of the reference impedance spectrum and the real-time impedance spectrum to obtain the hidden defect condition of the distribution network line. According to the invention, the efficiency of distribution network line hidden defect on-line detection of impedance spectrum can be improved.

The application provides a hardware-implemented sparse impedance spectrum fast measurement method and system. The system comprises an excitation signal generation and gain module, an impedance voltage conversion and data acquisition module, a signal demodulation module, a data uploading module and a host computer. The excitation signal generation and gain module generates a multi-frequency excitation signal and applies the signal to the impedance to be measured. The impedance voltage conversion and data acquisition module converts the impedance to be measured into a voltage signal and then performs analog-digital conversion, and inputs the signal into the signal demodulation module. A rearrangement factor is selected through simulation, and the spectrum downsampling without frequency collision is realized in hardware. The result is transmitted to the host computer through the data uploading module. According to the known frequency, the amplitude and phase change of the impedance to be measured are recovered through one-time hash inverse mapping, and the fast measurement of the sparse impedance spectrum is realized. The application has the characteristics that the spectrum downsampling without frequency collision is realized through one-time signal rearrangement, the data storage and operation amount is greatly reduced, and the fast measurement of the impedance spectrum is realized.

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.

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.

The invention discloses a data and model fusion driven power grid impedance online evaluation method, system, equipment and medium, and belongs to the technical field of power electronics, and the method comprises the steps: constructing a power grid impedance equivalent model under a weak power grid condition, introducing a disturbance instruction in a grid-connected inverter control link, and injecting a disturbance current into a power grid; collecting voltage and current waveforms before and after disturbance injection, and performing fast Fourier transform to obtain frequency spectrum data; calculating an impedance spectrum according to the spectrum result; constructing a mechanism model based on the Thevenin theory, establishing an artificial neural network data model, and performing fitting prediction on impedance; a data model and a mechanism model are fused, model parameters are corrected in real time, accurate sensing of the broadband impedance of the power grid is achieved based on part of frequency spectrum information, and the problems of accuracy of mechanism modeling and generalization of data-driven modeling are solved.

The application belongs to the technical field of seedling quality grading, and discloses a quality grading method for Platycladus orientalis seedlings in situ based on electrical impedance spectroscopy, which comprises the following steps: a Platycladus orientalis seedling in-situ measurement device is built for non-destructive measurement of root EIS in situ; an EIS-100 system is used to measure EIS parameters; based on a GSFS-FCM algorithm, input data are clustered, and the optimal cluster number K and the optimal cluster center coordinate matrix are output; according to the optimal cluster number K and the optimal cluster center coordinate matrix, the final membership degree is calculated and the classification is divided through the FCM algorithm, the quality grade to which the Platycladus orientalis seedling belongs is output, and the whole process from electrical impedance measurement to quality grading is completed. The above-mentioned grading method is adopted, the GSFS-FCM algorithm can automatically determine the classification number, automatically find the cluster center, reduce the iteration number of the algorithm, has high accuracy, and breaks away from the traditional grading method which relies on morphological parameters of the aboveground part.

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.

A computer-implemented method and system provides output data, wherein the output data includes a performance value of a perovskite-based solar cell. The method includes: (i) receiving input data, wherein the input data includes data from electrical impedance spectroscopy carried out on the solar cell or parts thereof, (ii) applying a trained function to the input data, wherein the output data is generated and (iii) providing the output data. A computer-implemented method also provides a trained function which is able to predict a performance value of a perovskite-based solar cell based on electrical impedance spectroscopy carried out on the solar cell or parts thereof.

An apparatus for determining a force Ftip applied to a tip of an electrical impedance spectroscopy probe includes a load cell, accelerometer, and a processing means. The probe tip has a substantially planar distal end for contacting human or animal tissue. The load cell measures the force Floadcell applied axially along a longitudinal axis when the probe tip is in contact with human or animal tissue. The accelerometer measures a gravity vector Aaxial. The apparatus includes a means for compensating for the mass of the probe tip using the measured force and the gravity vector to produce a calibrated measurement force F applied to the probe tip.

The application provides a grounding wire monitoring method and system, and relates to the technical field of grounding wire monitoring.The method comprises the following steps: collecting a voltage signal of an injection point and a current signal of a grounding loop; pre-processing the signals to obtain pre-processed signals; calculating impedance spectra of the grounding loop at different frequencies according to the pre-processed signals, and extracting key characteristic parameters in the impedance spectra; collecting environmental parameters and operating state data of power equipment, and fusing the key characteristic parameters to obtain fused data; adjusting a judgment threshold or a reference baseline corresponding to the key characteristic parameters by using the fused data; and judging the current grounding loop state by using the adjusted judgment threshold or reference baseline.The method of the application is based on impedance spectrum analysis, and overcomes electromagnetic interference and achieves the effects of adapting to dynamic baseline and distinguishing different electric leakage types through multi-stage signal processing, robust feature extraction and multi-dimensional data fusion analysis.

Such an apparatus, having a structure to measure a battery parameter of a battery of a plurality of batteries, can be implemented in a variety of applications. The apparatus can be configured to measure an alternating current (AC) electrical impedance of a battery cell by processing a difference between the battery cell and another battery cell. The battery cell under measurement experiences an AC excitation, while the other does not, with both battery cells sharing a common load current. This differential approach can reduce sensitivity to noisy battery load currents, which are common to both battery cells. This differential approach can also eliminate or substantially reduce a large direct current (DC) offset, i.e., the battery potential itself, under which AC signal measurements are burdened.

Systems and methods of monitoring medical therapies performed by wearable devices using electrical probes. In one example, a pulmonary physiotherapy device implements a treatment protocol function gated and modulated using electrical impedance sensors and metrics. The sensors operate to measure electrical impedance of bodily tissue. An electronic controller controls operation of the wearable device. The medical therapy can be modified based on the impedance measurements to maximize efficacy.

A method for determining a vascular endothelium functionality of an artery of a person, the method comprising: acquiring measurement data associated with a series of electrical measurements taken by an electrical impedance spectroscopy device; extracting an impedance time series associated with the impedance changes of the of the medium intervening between each pair of electrodes; filtering the impedance time series in the frequency domain to extract at least a low pass frequency, LPF, and a band limited frequency, BPF, component waveforms for each pair of electrodes; processing the LPF and BPF component waveforms obtained from each pair of electrodes to extract a set of biomarker parameter values, each biomarker parameter being indicative of a particular aspect of the endothelium functionality of the artery of the person; and determining an endothelium functionality index indicative of the vascular endothelium functionality of the artery of the person.

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 utility model relates to a water content monitoring device for a membrane electrode of a fuel cell. The device comprises a PCB substrate, a detection bonding pad and N first resistors, the detection bonding pad comprises N sub bonding pads, the number of the first resistors is N, and the N sub bonding pads are fixed on the PCB substrate; the N sub bonding pads are used for obtaining current signals of different areas in a membrane electrode unit in the fuel cell; for each sub-pad in the N sub-pads, one side, close to the PCB substrate, of the sub-pad is electrically connected with a first end of a first resistor through a through hole reserved in the PCB substrate; the second end of each first resistor is connected with an impedance tester through a line; the impedance tester is used for generating an impedance spectrum according to a voltage signal input by the first resistor, so as to generate moisture content distribution information based on the impedance spectrum. According to the scheme, the water content monitoring efficiency and accuracy of the membrane electrode unit are improved.