1674results about "Frequency measurement arrangement" patented technology

The invention provides a power grid multi-agent large model safety evaluation index calculation method, and relates to the technical field of intelligent control. The method comprises the following steps: acquiring a voltage change rate and a frequency change rate, dividing four stages according to disturbance starting and extreme points, pairing curve trends, judging delay and synchronization characteristics, extracting a continuous change structure, and generating a disturbance subsection evolution structure; according to the method, through staged analysis of node voltage and frequency change trends and combination of trend consistency judgment and abnormal segment identification, dynamic structure reconstruction and trend mapping of a disturbance process are realized, and coherence and precision of index response state identification are improved through trend boundary collection and frequency classification; cooperative characteristic identification is enhanced through the coupling direction and delay analysis of inter-node multi-parameter change, the node adjustment priority is defined through regulation and control response sorting, an adjustment path under multi-dimensional linkage is constructed, and the refined management and control capacity of disturbance response and the pertinence of control decision are improved.

The invention relates to the technical field of electrical fault detection, in particular to a photovoltaic inverter fault detection system based on an electric signal, and the system comprises a signal collection module which continuously collects the output electric signal of an inverter, records the amplitude, frequency and phase of the electric signal, and generates an original signal record; and based on the original signal record, screening the electric signal, eliminating noise and non-characteristic data, and generating screened signal data. According to the method, the time frequency characteristics of the signals are extracted in real time through continuous wavelet transform, and the sensitivity and accuracy of fault detection are improved. According to the detailed feature recognition method, even tiny abnormal waveforms or frequency deviations can be captured, and therefore early warning of potential faults is achieved. Meanwhile, the fault detection threshold value is dynamically adjusted through the environmental parameters, flexible response is allowed according to the actual operation environment change, the false alarm and missing alarm conditions are reduced, and the adaptability and the reliability are improved.

The invention provides a multi-band radio frequency power amplifier dynamic range adaptive test method and a system thereof. The method comprises the following steps: acquiring an output signal frequency spectrum of a tested radio frequency power amplifier, extracting characteristic frequency points including a center frequency and a bandwidth, matching the characteristic frequency points with a preset frequency band database, and automatically loading a test scheme of a corresponding frequency band. According to the method, the frequency bands are automatically matched through spectrum sensing, the test scheme is loaded, the multi-frequency-band characteristics can be rapidly adapted without manual parameter configuration, index missing test is avoided, and the switching efficiency is improved; dynamically optimizing test parameters by using a genetic algorithm, and accurately capturing a nonlinear distortion critical point while balancing coverage and efficiency; by combining multi-dimensional signal analysis and a deep learning model, the problem of missing detection of traditional single-domain analysis is solved, and the abnormal signal recognition capability is remarkably enhanced; through linear model correction, impedance dynamic matching and index threshold iteration, full automation and high precision of the test are realized, the environmental interference influence is effectively reduced, and a self-adaptive test system is constructed.

The invention provides a simultaneous multiband superheterodyne receiver based on Rydberg atoms, and relates to the technical field of microwave electric field measurement, probe light provided by a probe light laser and coupling light provided by a coupling light laser oppositely enter an alkali metal atom gas chamber; the microwave signal sources of the multiple wave bands generate two paths of signals, one path of microwave signal is emitted to the space through the local oscillator microwave electric field emission horns of the wave bands, and the microwave electric field receiving horns of the wave bands receive corresponding echo signals. After frequency mixing of each wave band, the microwave electric field emission horn irradiates the alkali metal atom gas chamber at the same time, microwave fields of multiple wave bands are sequentially coupled with multiple pairs of continuous adjacent Rydberg states, and superheterodyne receiving is carried out on microwaves of multiple wave bands at the same time; and superheterodyne and high-sensitivity detection of microwave signals of multiple wave bands can be realized.

The invention discloses a power grid visual diagnosis system based on multi-source data fusion, and relates to the field of power grid diagnosis systems. The system comprises an information acquisition module, an electrical fault alarm module, a non-electrical quantity fault alarm module, a fault discrimination module, a communication module and a fault recording module. Firstly, information of a power grid is collected through the information collection module, then the information is transmitted to the electrical fault alarm module and the non-electrical fault alarm module for monitoring, corresponding actions are made when abnormity occurs, then the information is transmitted to the fault judgment module, input information is analyzed, and the fault type is obtained; meanwhile, the fault recording module records and broadcasts the power grid; the communication module collects information of other modules in the system and exchanges information with the monitoring system. According to the method, the abnormal information of the power grid is monitored and alarmed in combination with the multi-source data, and the fault type is judged through the data model, so that the omnibearing monitoring of the power grid is realized, and data support is provided for a subsequent maintenance plan.

According to the new energy grid-connected electric energy metering method and device, broadband harmonic characteristic information and inter-harmonic characteristic information are respectively obtained according to preprocessed power grid voltage and power grid current; after the broadband harmonic characteristic information and the inter-harmonic characteristic information are input into the influence analysis topology network, a first error compensation parameter is calculated by using an electric energy metering error output by the influence analysis topology network; based on a non-sinusoidal signal simulation model, combining the preprocessed power grid voltage and power grid current with the step wave signal to obtain a non-sinusoidal wave signal; performing error compensation calculation on the non-sine wave signal to obtain a second error compensation parameter; obtaining time-varying error data of the electric energy meter by using historical operation data of the electric energy meter; a target error compensation parameter is calculated based on the first error compensation parameter, the second error compensation parameter and the time-varying error data of the electric energy meter, the electric energy meter performs electric energy metering based on the target error compensation parameter, an electric energy metering result is obtained, and the accuracy of new energy grid-connected electric energy metering is improved.

A broadband measurement method and apparatus for a power system, and a computer device, which relate to the technical field of broadband measurement. The method comprises: acquiring a target electrical signal; on the basis of a local mean decomposition algorithm, decomposing in a time domain the target electrical signal into a plurality of signal components having a single frequency; determining the instantaneous frequency of each signal component; on the basis of the instantaneous frequencies, determining a corresponding time-frequency transformation algorithm and a corresponding time-frequency transformation parameter; and on the basis of the corresponding time-frequency transformation parameter, using the corresponding time-frequency transformation algorithm to perform time-frequency transformation on each signal component, so as to obtain a broadband spectrum that comprises frequency-domain information corresponding to each signal component. The method is applicable to spectrum analysis performed on a voltage / current signal that includes a plurality of signal components, the calculation is quickly and precisely performed, the broadband measurement requirements of a new power system can be met, and a strong support is provided for constructing a wide-frequency-oscillation wide-area monitoring system for the power system.

The invention provides a satellite navigation interference detection and suppression system and method, and belongs to the technical field of signal analysis. The sensor module is used for determining a target area where a sensor is installed according to a target detection sky, and deploying and installing the sensor in the target area to obtain original signal data of a satellite; the signal processing module is used for standardizing the original signal data to obtain standard signal data and converting the standard signal data into a first frequency spectrum; the feature recognition module is used for analyzing features of the first frequency spectrum through fast Fourier transform and screening signal points with abnormal fluctuation; the interference analysis module is used for classifying the features of all the signal points and matching corresponding interference categories to obtain all interference categories of the original signal data; and the interference suppression module is used for adjusting parameters in real time to reduce interference by using an adaptive filter according to the dynamic characteristics of the interference category. The reliability of navigation signals is improved, and the anti-interference capability is enhanced.

The invention relates to an impedance measurement method and system. The method comprises the following steps: acquiring grid-connected point voltage, measurement frequency, disturbance amplitude and nth inverter grid-connected current of the multi-inverter grid-connected system; inputting the grid-connected point voltage into an improved phase-locked loop in a fundamental wave and disturbance control unit to generate a power grid frequency and a power grid phase; inputting the power grid phase and the nth inverter grid-connected current into the current control loop to generate a fundamental current control instruction; inputting the measurement frequency, the disturbance amplitude and the power grid frequency into the disturbance control ring to generate a disturbance instruction; inputting the disturbance instruction and the fundamental current control instruction into the modulation ring, generating a control driving signal according to a modulation strategy of an inverter, and controlling each inverter switch; and obtaining the controlled grid-connected point voltage through an impedance calculation unit, and generating the impedance of the inverter to be tested and the impedance of the power grid. By adopting the method, disturbance can be injected efficiently at low cost so as to measure impedance.

The invention relates to the related technical field of distribution transformer insulation aging, in particular to a frequency domain diagnosis method, system and device for distribution transformer insulation aging and a medium, and the method comprises the steps: carrying out the frequency response test of a to-be-tested transformer, and obtaining a first frequency response curve; performing a frequency response simulation test on a transformer equivalent circuit model pre-constructed based on the to-be-tested transformer to obtain a second frequency response curve; constructing a target function based on the deviation of the first frequency response curve and the second frequency response curve; taking element parameters in the equivalent circuit model of the transformer as position vectors, taking the objective function as a fitness function, and adopting a multi-objective particle swarm algorithm to solve the element parameters to obtain optimal values of the element parameters; respectively comparing the optimal values of the element parameters with corresponding normal values to obtain insulation aging degrees; according to the method, the insulation aging degree can be obtained by comparing the element parameters obtained through optimization with the normal unaged element parameters.

The invention relates to an electric power system broadband measurement method and system based on a wavelet packet and SVMD, and belongs to the technical field of electronic measurement. The method comprises the following steps: acquiring frequency information corresponding to a circuit signal of each measurement point in a circuit system; performing wavelet packet decomposition on the frequency information, and determining an optimal wavelet basis for broadband measurement of the power system; performing multilayer decomposition on the frequency information according to the optimal wavelet basis to obtain a plurality of wavelet frequency bands; performing component extraction on the wavelet frequency band to obtain a harmonic component corresponding to the wavelet frequency band; de-noising the harmonic components by using a wavelet coefficient correlation algorithm to obtain de-noised harmonics; decomposing the noise reduction harmonic wave according to an EMD algorithm to obtain a signal residual error meeting a preset stop condition; and calculating to obtain measurement and calculation data corresponding to each harmonic waveform according to the signal residual error. According to the technical scheme, the time-frequency characteristics of the signals can be captured more accurately, and the method has better performance on non-stationary signals and signals with complex frequency structures.

The invention relates to the technical field of electrical parameter testing, in particular to a high-low voltage frequency converter testing system which comprises a sampling point calibration module, a frequency cross-grade identification module, a current response re-sequencing module, a dynamic interference blocking module and an operation parameter output module. According to the method, the amplitude of the voltage sampling point is mapped into the trigonometric function curve, the waveform trend is deduced in combination with the amplitude change angle, a time delay calibration mechanism based on periodic trend identification is established, and the sampling point time sequence precision in different gear switching scenes can be effectively adapted. According to a combined judgment mode of the current rise rate direction and the frequency jump amplitude, a cross-cycle dynamic judgment path is constructed, a frequency jump index can be identified from a non-stable operation state, and the perception capability of a non-linear operation behavior is improved. A current response sorting reconstruction process is introduced, and the sorting matching capability of inconsistent response sequences is enhanced through cross analysis of frequency gears, current response directions and load states.

The invention provides a power distribution network abnormal state sensing method and system based on data processing, and relates to the technical field of data processing, and the method comprises the steps: obtaining a target function, and setting a differential evolution parameter; the differential evolution parameters comprise population size, iteration times, variation factors and crossover probability; the configuration of differential evolution parameters is iteratively optimized, various operation data are preprocessed, abnormal value and noise removal and normalization processing are included, and processed data are obtained; and extracting characteristic indexes reflecting the running state of the power distribution network from the processed data, wherein the characteristic indexes comprise statistical characteristics, frequency spectrum characteristics and time frequency characteristics of voltage and current. According to the invention, through real-time data acquisition, feature extraction, state evaluation and abnormity identification and positioning, comprehensive monitoring and timely early warning of the operation state of the power distribution network are realized, and the safety and stability of the power distribution network are effectively improved.

A fully distributed island micro-grid attack elasticity control system and method are provided. The method includes following specific steps: collecting basic information of a local AC micro-grid bus of a distributed power generation unit and basic information of a neighbor distributed power generation unit connected through a directed communication topology; predicting, based on a dynamic equation of the distributed power generation unit, a sequence of states thereof within a set period of time, namely, the predicted sequence of states; judging whether a system is under attack according to a comparison result of the predicted sequence of states and a real-time state sampling value of a micro-grid, to obtain a sequence of optimal auxiliary control inputs ui*; and calculating an optimal angular frequency reference value ωi* at the next time point according to the sequence of optimal auxiliary control inputs ui*.

The invention relates to an AC-DC integrated grounding fault positioning method and system, and the method comprises the steps: collecting the potential change data of a DC power supply system and the frequency characteristic data of an AC power supply system, and determining the electrical signal characteristics of stray current corrosion; decomposing the electric signal by using wavelet transform, and extracting direct-current and alternating-current components; determining a fault type according to the component amplitude; analyzing the potential gradient and the stray current flow direction in combination with a line topological structure, and determining the position of a fault point; measuring resistance to determine a grounding loop, and analyzing the correlation between corrosion distribution and electrical parameter characteristics; evaluating the influence of corrosion on the grounding path in combination with the material resistivity; according to the method, faults can be accurately recognized, fault points can be accurately positioned, the corrosion degree and the influence of the corrosion degree on the system can be evaluated, and effective support is provided for safe operation and maintenance of a subway power supply system.

The invention provides a power grid frequency detection method, system and device and a medium, and the method comprises the steps: carrying out the narrowband signal decomposition of an obtained input voltage signal of a power grid through a null-space tracking algorithm, and obtaining a fundamental main mode component of the input voltage signal; performing low-pass processing on the fundamental wave main mode component to obtain a fundamental wave signal of the fundamental wave main mode component; performing discrete Fourier transform on the fundamental wave signal to obtain phase information of the fundamental wave signal; according to the phase information of the fundamental wave signal, calculating phase deviation information of the fundamental wave signal in pre-selected adjacent cyclic waves to obtain frequency estimation information of the power grid; according to the invention, narrow-band decomposition is carried out on an input voltage signal through a null-space tracking algorithm, so that a fundamental main mode can be accurately extracted; and phase deviation information can be determined based on discrete Fourier transform, so that when the interference frequency of the power grid is close to the fundamental frequency, high separation precision can be kept, and the accuracy of power grid frequency estimation can be improved.

The invention provides a new energy primary frequency modulation acquisition method and device based on self-correlation frequency fitting, and the method comprises the steps: carrying out the digital-to-analog conversion and low-pass filtering of a three-phase current / voltage signal of a secondary side loop of a power grid in a primary frequency modulation system of a new energy station, describing a self-correlation function of the current / voltage signal after low-pass filtering through a fitting model, and carrying out the self-correlation frequency fitting. Constructing a loss function to represent a residual sum of squares between the current / voltage signal autocorrelation function and the fitting model, and minimizing the loss function by using a nonlinear least square method; and taking the frequency obtained through the fitting model as the estimated power grid frequency. According to the method, the self-correlation function is used for frequency fitting, the power grid frequency can be rapidly solved, the precision is high, the robustness is good, and the timeliness is high.

The invention relates to a power grid anomaly detection method and device, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: acquiring real-time power data of a target power system; the target power system comprises a plurality of power areas; according to the real-time electric power data, calculating an abnormal probability value of the target electric power system and an abnormal weight of each electric power region; when the abnormal probability value is greater than a preset threshold value, calculating a failure risk value of each power region in combination with the abnormal probability value and the abnormal weight of each power region; and determining the influence of the power region on the target power system according to the failure risk value. By adopting the method, the abnormal state can be accurately detected.

The invention relates to a magnetic core loss prediction method and device for a magnetic element, and the method comprises the steps: obtaining historical data sets of different magnetic core materials, thereby considering the influence of the temperature on the magnetic core loss, carrying out the temperature correction of a preset SteinMazz equation according to the historical data sets, obtaining a target SteinMazz equation, and carrying out the prediction of the magnetic core loss of the magnetic element. Therefore, loss prediction can be carried out on the magnetic core material in the historical data set through the target Steinmaz equation, and an updated data set of the prediction value of the temperature factor is obtained. Furthermore, the influence of the magnetic flux density data and the frequency on the magnetic core loss can be considered, the updated data set is merged according to the magnetic core material, the magnetic flux density data and the frequency, a merged data set is obtained, and then the preset prediction model can be trained through the merged data set. The training of the preset prediction model on the magnetic flux density data and frequency is added, so that the predicted magnetic core loss of the target prediction model on the magnetic element better conforms to the actual situation.

The invention relates to the technical field of frequency detection, in particular to a frequency measurement method and device based on Kalman filtering, electronic equipment and a storage medium, and the method comprises the steps: obtaining a posterior estimation value of frequency measurement data at a previous moment and an observation value at a current moment; calculating a prior estimation value at the current moment by using the posterior estimation value at the previous moment, calculating an observation error between the prior estimation value at the current moment and the observation value at the current moment, and judging whether the observation error is greater than a preset error threshold value or not; and if the observation error is greater than a preset error threshold value, updating the prior estimation value at the current moment by using a preset Kalman filter, and taking the updated prior estimation value at the current moment as an output value of the frequency measurement data at the current moment. Therefore, the problem that the frequency measurement requirements of complex signal processing, real-time monitoring and quick response to signal change are difficult to meet in the related technology is solved, accurate system state estimation can be provided, and the method has good real-time updating and signal processing capabilities.

The invention discloses a multi-task parallel test method for a multi-station FCT test system, and relates to the technical field of parallel tests.The method comprises the steps that a plurality of target PCBA products are loaded to corresponding stations on a needle bed respectively, and starting signals are obtained; scanning the target PCBA product to obtain a plurality of pieces of production work order information and a plurality of test programs; executing a plurality of test programs to obtain a plurality of test signal sets; carrying out test qualification authentication; load working signals are collected; and judging whether the plurality of load working signal feature sets meet a preset requirement or not, and displaying a qualified station of the product test through a machine indicator lamp. The technical problems that PCBA product testing efficiency is low, accuracy is difficult to guarantee and product quality control is not comprehensive in the prior art are solved, and the technical effects that the efficient process of conducting product testing at multiple stations at the same time is achieved, the testing efficiency and accuracy are improved, and the product quality is effectively guaranteed are achieved.

The invention discloses a frequency measurement circuit and a frequency measurement method, belongs to the technical field of frequency measurement, and mainly solves the problems that the existing frequency measurement is large in frequency error, low in frequency measurement speed and narrow in frequency measurement bandwidth, and cannot meet the requirements of radar communication. The frequency measurement circuit comprises an FPGA control module, a reference clock circuit connected with the FPGA control module, a DDS frequency output circuit, a phase discrimination frequency control circuit, a frequency mixer connected with the phase discrimination frequency control circuit, and a radio frequency input circuit connected with the frequency mixer. According to the frequency measurement technology, the DDS output frequency is directly collected according to the characteristic that the FPGA collects the low frequency, the DDS output frequency serves as the phase discriminator phase discrimination frequency, frequency measurement is conducted in a phase locking mode, and the frequency measurement precision is high; the phase discriminator is set to have a fixed frequency dividing ratio, the phase discriminator is configured with a fixed register, a DDS frequency sweeping mode is adopted, and the frequency measurement time is short by changing the phase discrimination frequency of the phase discriminator to the output frequency of the phase-locked loop; and the frequency measurement bandwidth is increased by using a radio frequency input frequency division mode.

The invention relates to the technical field of electric energy metering, and discloses an electric energy metering method and device and a related product. The method comprises the following steps: acquiring voltage and current sampling data in multiple cycles; performing signal decomposition on the voltage and current sampling data by using a preset signal decomposition algorithm to obtain voltage and current frequency components; for any target component in the voltage frequency components, calculating the dot product sum between the current frequency components with the same frequency as the target component to obtain target electric energy; generating an electric energy metering result according to each target electric energy; the dot product sum between the voltage sampling data and the current sampling data is calculated with the single-cycle waves as the metering period, and electric energy of all the single-cycle waves is obtained; positive and negative electric energy sets are obtained after classification; and adding the elements in the set to obtain total full-wave electric energy. According to the invention, a set of complete electric energy metering scheme is provided, electric energy metering can be carried out from two dimensions of time domain and frequency domain, and detailed basis and direction are provided for improving electric energy quality.

The invention particularly relates to a miniaturized broadband instantaneous frequency measurement receiver and a corresponding data processing method. The miniaturized broadband instantaneous frequency measurement receiver comprises a signal input port used for receiving an original radio frequency signal; the amplifying and filtering module is used for amplifying and filtering the original radio frequency signal and then outputting a first radio frequency signal; the first power divider is used for splitting the first radio frequency signal and outputting the first radio frequency signal to the multi-channel power division phase discrimination assembly; the multi-channel power division and phase discrimination assembly comprises a plurality of power division and phase discrimination modules and is used for carrying out instantaneous measurement on the signal frequency of the first radio frequency signal and outputting multi-channel video signals; the frequency measurement coding module is used for performing frequency measurement processing on the video signal and outputting a frequency code; wherein the signal input port is connected with the amplification filtering module and the power division phase discrimination module through microstrip lines; the power division phase discrimination module is connected with the frequency measurement coding module through a glass insulator. The size, the volume and the weight of the device all meet the requirement for miniaturization.

The embodiment of the invention discloses an off-line monitoring method and device for the state of a transformer winding, equipment and a storage medium. The method comprises the steps of obtaining off-line frequency response test data, at least comprising a smooth frequency response curve, of a transformer; obtaining a resonance frequency and a resonance peak value according to the smooth frequency response curve, and calculating a first transformer capacity, a first no-load loss and a first short-circuit loss under the resonance frequency; utilizing the first transformer capacity, the first no-load loss, the first short-circuit loss and a preset multi-dimensional inferior fusion model to obtain a first comprehensive index used for reflecting the performance change of the transformer winding under the resonant frequency; and determining the current winding state of the transformer according to the first comprehensive index and a predetermined second comprehensive index. By means of the mode, higher sensitivity and reliability can be displayed in diagnosis of winding states such as winding deformation faults, and the method has important significance in prolonging the service life of a transformer and improving the operation reliability and economical efficiency of a power grid.

The invention discloses an electric power system operation state analysis and evaluation method and device, and the method comprises the steps: carrying out the line node division of an electric power system, combining the load time division of a power supply region, and further discriminating the load change based on the load time; meanwhile, fluctuation nodes are identified by using the operation states of the line nodes and the power grid operation fluctuation degree is analyzed, so that the operation stability of the power system is evaluated. According to the method, limitation of traditional overall evaluation is broken through, fine transformation from macroscopic to microscopic and from static analysis to dynamic monitoring is achieved, the actual operation condition of the power system can be comprehensively and accurately reflected, and clear direction guidance is provided for formulating a targeted regulation and control strategy. In addition, the possibility that abnormal operation of the power system is covered can be effectively reduced, and potential risks are reduced to the maximum extent.

The invention discloses a bus voltage multi-dimensional real-time monitoring and analyzing method, system, equipment and medium, and belongs to the technical field of power system monitoring and fault prediction.The method comprises the steps that high-frequency synchronous sampling is conducted on bus voltage signals, discrete time sequence voltage signals are obtained and preprocessed, preprocessed voltage signals are obtained, and the discrete time sequence voltage signals are obtained; the method comprises the following steps: synchronously extracting multi-dimensional characteristic parameters of voltage, obtaining a characteristic parameter set, calculating a health degree index comprehensively representing a voltage state by utilizing a dynamic weighted fusion algorithm based on the characteristic parameter set, calculating an abnormal degree of a current value according to a historical data sequence of the health degree index, and performing fault grade judgment according to the abnormal degree. And performing trend extrapolation based on the health degree index and the historical data sequence of the key parameters in the characteristic parameter set, and generating predictive maintenance suggestions. According to the method, the crossing from passive alarm to predictive maintenance is realized, and the intelligent level and the operation and maintenance reliability of state monitoring of the power system are remarkably improved.

The present application relates to a device and method for surveying a power line-buried path, wherein the device includes a transmitter which selects a balanced / unbalanced voltage to output input and rectified output power as a current pulse in the form of an unmodulated pulse or a frequency-modulated signal when a current pulse signal is transmitted to a conductor (power line) of a public distribution network, and a receiver in which a plurality of magnetic field sensors inductively couple the pulse or the frequency-modulated signal within a near magnetic field distance to obtain a difference value in each direction to obtain a depth.

The invention discloses an AC synchronous electric energy metering method and system based on a GPS Beidou satellite clock, and relates to the technical field of electric energy metering, and the method comprises the steps: receiving a satellite signal, and analyzing the quality score of the satellite signal; according to the quality score of the satellite signal and the time reference data, generating a high-precision unified time reference; performing regional error correction on the high-precision unified time reference based on the high-precision unified time reference in combination with differential time service information of a ground base station to generate a standard time reference; acquiring actual frequency data of a power grid in real time by using power grid frequency detection equipment, calculating power grid frequency deviation, and generating a power grid frequency deviation correction factor; and dynamically adjusting the standard time reference based on the power grid frequency deviation correction factor, and performing accurate time sequence synchronization on the electric energy metering data in the alternating current power grid according to the adjusted standard time reference. The dynamic adaptability, the precision and the reliability of the electric energy metering method are remarkably improved.