15 results about "Harmonic phase" patented technology

The invention relates to the technical field of power monitoring, in particular to an online monitoring method and system for a power control cabinet. The method comprises the following steps: acquiring a time domain signal, tracking a fundamental wave frequency, adjusting a sampling window, and performing Fourier transform to obtain a harmonic amplitude and a phase; harmonic waves are divided into harmonic wave correlation groups according to association rules, harmonic wave phase consistency coefficients are calculated to weight the total energy in the groups, and weighted harmonic wave energy is obtained; total inter-harmonic energy is calculated, and an inter-harmonic structure factor is obtained based on the spectral entropy. And acquiring a real-time load rate and a change rate, and calculating a synchronous change coefficient and a load factor. And summing the weighted harmonic energy and the corrected inter-harmonic energy to obtain total distortion energy, and obtaining a comprehensive distortion index according to the total distortion energy. According to the scheme, the structured inter-harmonics possibly caused by the early failure of the equipment can be found earlier, and the requirements of early warning and predictive maintenance are met.

The invention relates to the technical field of unmanned aerial vehicle nondestructive testing, and discloses an unmanned aerial vehicle precision part rapid detection system based on multi-sensor fusion. Low-frequency harmonic vibration excitation is applied through a micro vibration excitation module, and a phase offset auxiliary harmonic signal is generated in combination with a multi-harmonic phase synchronous modulation module; and the defect response of the precision part is amplified. The multi-sensor array synchronously collects vibration, optical and thermal response data, and data calibration is carried out through the sensor array self-calibration network. And the defect pattern library pre-matching engine matches the current detection data with the historical defect pattern. And the fusion processing unit performs weighted fusion on the multi-modal detection data, adjusts detection parameters according to a detection result through a closed-loop feedback loop, and triggers iterative detection. According to the invention, low-frequency harmonic vibration excitation is applied through the micro vibration excitation module, and the multi-harmonic phase synchronous modulation module is combined to superpose auxiliary harmonic signals of phase deviation, so that the identification capability of micro defects is improved.

The present invention provides a method for compressing a signal, the method comprising: obtaining a main signal via a signal recording module; modeling a model signal of the main signal via a processor by: obtaining a sampled signal via the processor; obtaining a windowed signal via the processor; and extracting, via the processor: a fundamental frequency waveform having a fundamental magnitude and a fundamental phase; and at least one harmonic frequency waveform having a harmonic magnitude and a harmonic phase; wherein the model signal comprises the fundamental frequency waveform and the at least one harmonic frequency waveform; calculating, via the processor, an error signal between a reconstructed signal and the main signal; determining, via the processor, an optimal gain according to at least: an averaging step providing an average, a predefined threshold, and a scaling signal, wherein the scaling signal is a historical error signal scaled by iteratively: averaging a difference between the error signal and the scaling signal, wherein the optimal gain comprises a predefined gain when the average satisfies the predefined threshold; determining, via the processor, an index from a residual signal by: determining the residual signal; vector quantizing the residual signal; and indexing the vector quantized residual signal; synthesizing, via the processor, a compressed signal, wherein the compressed signal comprises: the fundamental phase; the fundamental magnitude; the harmonic phase; the harmonic magnitude the optimal gain; the index. Thus, the compression method preferably overcomes problems associated with current compression techniques, and provides a suitable technique for compressing a signal that can be used to infer a type of load on a circuit.

The invention provides a harmonic phasor estimation method and a harmonic phasor estimation system. The harmonic phasor estimation method comprises the following steps: extracting the center frequency of each component of a signal based on a matrix pencil method; performing complex demodulation on each component according to the center frequency of each component; and obtaining a baseband phasor of each component according to a filtering result of each component demodulated by the complex number based on the FIR filter of the flat-top window. The method can be used for phasor measurement of fundamental waves and harmonic waves, and is simple, wide in application range and high in estimation precision.

The present application relates to a kind of adaptive band optimization chorus sound separation method and system based on harmonic maintenance, first, the signal is collected by microphone array and time delay compensation and multi-channel time-frequency transformation are carried out;Sound source spatial positioning and initial band division are carried out using MUSIC algorithm;Using the greedy optimization strategy, the band boundary is dynamically adjusted and optimized by maximizing the objective function including signal-to-noise ratio and harmonic integrity measure;Then, the fundamental frequency is obtained by harmonic analysis and detection, and the time-varying harmonic trajectory is tracked across frames by Viterbi algorithm;On this basis, combined with MVDR beam forming and the introduction of harmonic maintenance factor, enhanced time-frequency representation is obtained by soft time-frequency mask;Finally, inverse short-time Fourier transform time-domain reconstruction and synchronous harmonic phase are carried out.The present application realizes the accurate allocation of voice part spectrum, effectively reduces the overlap interference, protects the overtone column of human voice while accurately separating, significantly improves the timbre fidelity and naturalness of separated voice part.

The application relates to a cable insulation safety evaluation method and system based on harmonic data preprocessing, and the method comprises the following steps: collecting voltage or current data of a cable to be detected; according to the periodic characteristics of harmonics, harmonic data is updated after reaching a preset fixed time each time, the process of the harmonic data updating comprises the following steps: extracting harmonics of the voltage or current data through a wave trap, and compensating the harmonic phase by using a repetitive predictive controller to obtain extracted harmonics; multiplying the extracted harmonics by an amplitude gain module to compensate the harmonic amplitude and obtain optimized harmonics; subtracting the optimized harmonics from the original voltage or current data to obtain fault data; performing traveling wave decoupling on the fault data, and judging the fault type and fault distance of the cable according to the traveling wave signal obtained through decoupling. Compared with the prior art, the application realizes rapid evaluation of cable insulation safety and rapid and accurate positioning when the insulation is damaged.

The application provides a multi-harmonic superposition control method and device for a synchrotron. The method comprises: obtaining a current cavity fundamental wave signal, a current cavity harmonic wave signal and a current beam signal; calculating a first phase difference between the current cavity fundamental wave signal and the current beam signal based on the current cavity fundamental wave signal and the current beam signal; performing phase compensation on the current cavity fundamental wave signal based on the first phase difference and a first preset phase difference to obtain a first fundamental wave signal; calculating a second phase difference between a harmonic wave signal corresponding to the current cavity fundamental wave signal and the current cavity harmonic wave signal based on the current cavity fundamental wave signal and the current cavity harmonic wave signal; performing phase compensation on the current cavity harmonic wave signal based on the second phase difference and a second preset phase difference to obtain a first harmonic wave signal; and synthesizing a radio frequency signal based on the first fundamental wave signal and the first harmonic wave signal. Through the application, the phase deviation of each harmonic of the radio frequency signal is reduced, and the phase of the radio frequency signal is accurately controlled.

The application relates to the field of electric digital processing, in particular to a power grid harmonic identification method and system based on deep learning, which comprises the following steps: inputting processed voltage data and current data into an LSTM model, outputting predicted data of voltage and current, obtaining voltage sequences and current sequences after processing, performing window division on the voltage sequences and the current sequences, obtaining local waveform differences in combination with amplitude spectra of corresponding windows, obtaining harmonic amplitude sequences by the amplitudes of the frequency corresponding to odd harmonics in the window sequence amplitude spectrum, obtaining harmonic amplitude change sequences after processing, obtaining harmonic similarity in combination with the local waveform differences, obtaining the harmonic contribution degree of a load feeder by using the harmonic amplitude sequences of different odd harmonics in the common coupling point voltage sequence to obtain the integrated harmonic similarity of the recognition significance degree, and sorting the harmonic contribution degrees and selecting a preset proportion of harmonic contribution degrees that meet preset conditions. The application has the effects of accurately locating a harmonic source and improving harmonic source identification accuracy.

The invention relates to the field of electric digital processing, in particular to a power grid harmonic recognition method and system based on deep learning, and the method comprises the steps: processing collected voltage data and current data, inputting the processed data into an LSTM model, outputting the prediction data of voltage and current, obtaining a voltage sequence and a current sequence after processing, carrying out the window division, and obtaining a current sequence; obtaining a local waveform difference by combining the amplitude spectrum of the corresponding window, obtaining a harmonic amplitude sequence through the amplitude of the frequency corresponding to the odd harmonic in the amplitude spectrum of the window sequence, obtaining a harmonic amplitude change sequence after processing, and obtaining harmonic similarity by combining the local waveform difference; the harmonic amplitude sequences of different odd harmonics in the common coupling point voltage sequence are utilized to obtain the harmonic contribution degrees of the load feeder line by integrating the significance degree and the harmonic similarity, the harmonic contribution degrees are sorted, and the harmonic contribution degrees with the preset proportion are selected to meet the preset condition. The method has the advantages that the harmonic source can be accurately positioned, and the harmonic source identification accuracy is improved.

The application discloses a bearing fault acoustic detection method and system based on fractional harmonic phase-locked amplification, acoustics signals of a target motor are acquired, the shaft rotation frequency of the motor shaft is measured in real time, and is synchronized to a fractional phase-locked loop; according to the geometric parameters of the bearing, the bearing fault characteristic frequency is calculated, the bearing fault characteristic frequency is a non-integer multiple of the shaft rotation frequency, a reference signal synchronized to the bearing fault characteristic frequency is generated through the fractional phase-locked loop, and the acquired acoustics signals and the generated reference signal are detected in a phase-sensitive manner through a phase-locked amplifier; specifically, the acoustics signals and the reference signal are quadrature demodulated to generate in-phase components and quadrature components, direct current components are extracted through low-pass filtering, and then the vibration amplitude and phase information corresponding to the bearing fault characteristic frequency are calculated; according to the comparison between the vibration amplitude and a preset baseline, harmonic consistency and phase stability, the bearing fault type and severity are determined.

The invention discloses a method for identifying first third-order harmonic waves of unbalanced mass of a hemispherical resonator based on vibration excitation, and belongs to the field of parameter identification of hemispherical resonators. The method solves the problems of low leveling efficiency and precision caused by difficult data identification and long measurement time of an existing method for identifying the first third-order harmonic waves of the unbalanced mass. Under vibration excitation, the vibration amplitude and the standing wave azimuth angle of the hemispherical harmonic oscillator are associated with the first-order harmonic and the third-order harmonic of the unbalanced mass; under vibration excitation, the vibration amplitude and the standing wave azimuth angle of the hemispherical harmonic oscillator are associated with the second-order harmonic of the unbalanced mass. And the first three-order harmonic amplitudes and azimuth angles are solved by constructing a corresponding coupling relationship. The method is mainly used for identifying the first third-order harmonic waves of the unbalanced mass of the hemispherical harmonic oscillator.

This invention discloses a sound source identification method and system based on the nonlinear harmonic phase conjugation method (PCD). The method involves acquiring the sound pressure gradient time-domain signal of the target sound source using a pre-constructed planar microphone array. After performing a fast Fourier transform on the sound pressure gradient time-domain signal to obtain the sound pressure gradient frequency-domain signal, a sound pressure gradient frequency-domain signal that meets the resolution requirements for reconstructing the sound field is selected as the higher harmonic sound pressure gradient signal. The sound field of the target sound source is reconstructed by establishing the phase conjugation method and the higher harmonic sound pressure gradient signal using dipole source emission based on the sound pressure gradient time-domain signal. This allows personnel to identify the target sound source through the reconstructed sound field. This method improves the resolution of sound field reconstruction by using the nonlinear harmonic phase conjugation method for sound source identification and is not limited by the near-field limitation of evanescent waves.

The application discloses a kind of based on geometric error comprehensive measurement and unified parameterization hemispherical resonator vibration performance evaluation method, it is related to optical element processing field, to solve the lack of comprehensive evaluation method of hemispherical resonator vibration performance based on multiple source geometric error in prior art.The technical points include: measuring hemispherical resonator multi-source data, convert measurement data to unified coordinate system and unified circumferential reference;Further error separation is carried out to measurement data, obtain the circumferential distribution geometric error and position size geometric error of hemispherical resonator;Circumferential harmonic decomposition is carried out to circumferential distribution geometric error, obtain each error circumferential harmonic amplitude, circumferential harmonic phase and global circumferential harmonic complex amplitude, and position size geometric error is combined, and the geometric error parameter set of hemispherical resonator is constructed;Geometric structure is constructed to hemispherical resonator by geometric error parameter set, and the vibration performance of hemispherical resonator is carried out finite element analysis.

This invention relates to the field of power electronic converter control technology, and discloses a harmonic suppression control system and method for a grid-type converter. The method includes: maintaining an internal synchronization phase angle and extracting the complex vectors of each harmonic based on this angle; subsequently calculating the harmonic phase-locked equivalent quantity including a superlinear weighting factor to characterize the pulling strength of the harmonic components on the synchronization phase angle. The control logic generates voltage suppression commands based on the harmonic complex vectors to improve the output waveform, and injects the filtered harmonic phase-locked equivalent quantity as negative feedback into the frequency control loop to achieve frequency decoupling. This invention effectively decouples the interference mechanism between harmonic regulation and fundamental synchronization, suppressing grid voltage distortion while eliminating low-frequency slow-motion oscillations, ensuring stable operation of the grid-type converter in weak grid and high background harmonic environments.

The application discloses a method, device, medium and equipment for suppressing harmonic interference of a controllable source, and the method comprises the following steps: obtaining the amplitudes of second-order harmonic, third-order harmonic and fourth-order harmonic signals based on original data of the controllable source; obtaining a preset signal waveform of each order of harmonic based on the scanning start and end frequencies of a fundamental wave and the amplitudes of each order of harmonic signal; obtaining order harmonic related data based on the preset signal waveform of each order of harmonic and the original data of the controllable source for the preset signal waveform of each order of harmonic; and subtracting the order harmonic related data from the original data of the controllable source to obtain controllable source data after the order harmonic is removed. The method for suppressing harmonic interference of the controllable source based on the correlation characteristics can better suppress the harmonic signals of the controllable source, the signal-to-noise ratio of the obtained controllable source data is obviously improved, the harmonic interference suppression effect is obvious, and the controllable source data imaging effect is effectively improved.