2691 results about "Wide band" patented technology

The invention discloses a method for preparing a single-layer tungsten diselenide nanoband based on a space confinement strategy. By changing the flow and the growth time of hydrogen, effective control on the width and the thickness of a nanoband can be realized. The method comprises the following steps: uniformly spraying tungsten trioxide powder to one substrate, then covering the substrate by the other substrate, and forming micro reaction space which is of a 'sandwich'-like structure. Growth of a tungsten diselenide nanoband is carried out by utilizing a constant-pressure chemical vapor deposition method; physicochemical characteristics of a one-dimensional transition metal chalcogenide strongly depend on suspension key types on the edge of the one-dimensional transition metal chalcogenide, metallic properties are displayed by an ultranarrow band, and conversion from the metallic properties to semiconductor properties can be displayed from the edge to the center of a wider band; the tungsten diselenide nanoband is widely applied to micro-nano photoelectric devices due to the special property; industrial production of the tungsten diselenide nanoband can be realized through an experimental method of the invention.

The invention provides a directional energy multi-target interference system based on an ultra-wideband phased array technology, and the system integrates signal perception, target recognition, interference signal generation and phased array control, so as to achieve the precise interference of an unmanned aerial vehicle cluster. The signal sensing module scans an airspace target through the ultra-wideband phased-array antenna array and obtains spectrum characteristics of a target signal. The target identification module analyzes signal features, identifies an individual target and predicts a motion track and a communication protocol of the individual target. And the phased array control module calculates and adjusts antenna beam forming parameters, and dynamically controls the radiation direction, phase and transmitting power of the antenna. The interference signal generation module generates a matched interference waveform based on the target communication protocol and the trajectory information. The ultra-wideband phased-array antenna array adopts a digital beam forming technology. According to the invention, efficient and accurate directional energy interference can be realized under multiple frequency bands, the confrontation capability of the unmanned aerial vehicle cluster is improved, and the method is suitable for defense tasks in electronic warfare and complex electromagnetic environments.

The present disclosure relates to the technical field of back contact solar cells, and in particular relates to a combined passivation back contact solar cell having front wide band gap doping, and a preparation method therefor. The solar cell comprises a silicon wafer, and a first semiconductor layer, a second semiconductor layer and a third semiconductor layer arranged on the front face of the silicon wafer. The third semiconductor layer comprises a second tunneling oxide layer and a third doped polycrystalline silicon layer, provided in sequence from inside to outside. The third doped polycrystalline silicon layer is a doped polycrystalline silicon layer containing a first doping element and a second doping element, the first doping element being phosphorus, and the second doping element comprising any one of carbon and oxygen. Furthermore, the band gap width of the third doped polycrystalline silicon layer is ≥1.6eV. The present disclosure, while ensuring a passivation effect, can greatly decrease device investment costs, greatly reduce parasitic absorption of a third semiconductor layer on the front surface of a cell, and increase short-circuit current of the cell, thereby increasing cell conversion efficiency.

The invention is suitable for the technical field of fault diagnosis, and provides a distributed power transmission line fault diagnosis method based on ground potential end transient information perception, and the method comprises the steps: collecting a broadband transient signal of each node ground potential end of a power transmission line; synchronously acquiring an electromagnetic transient signal and an environmental parameter through the composite sensing unit; performing dynamic filtering correction on the broadband transient signal according to a preset transmission line impedance matching model; a deep learning model is adopted to perform hybrid processing on the corrected broadband transient signals and electromagnetic transient signals, traveling wave head time-frequency features and power frequency abrupt change features are extracted, and fault probability and type classification results are output; verifying a fault positioning result through a multi-stage verification mechanism; the extracted characteristic quantity is preprocessed at the edge side of the detection terminal, and the processed data is transmitted to a master station system through an encryption protocol, so that the fault diagnosis accuracy of the distributed power transmission line is effectively improved.

The invention particularly relates to a leakage current testing method, device and system for an intelligent circuit breaker, and relates to the technical field of electrical safety detection. A composite signal generation and injection module; a broadband signal acquisition and conditioning module; and a line fault positioning and impedance analysis module. According to the invention, the composite signal generation module realizes the non-interference isolation injection of a leakage current signal and a high-frequency positioning signal, and guarantees the high fidelity of data through adaptive filtering, multi-channel synchronous sampling and high-precision timing. The line positioning module integrates TDR and a frequency domain impedance method, and through multi-frequency point deviation correction and topology-GIS association, the fault type is accurately identified, and the test and troubleshooting period is significantly shortened.

The invention provides an underwater sonar target detection system and method. The underwater sonar target detection system comprises an optical fiber hydrophone array module which comprises a plurality of optical fiber hydrophone units, each unit comprises an optical fiber Bragg grating sensor and a sound pressure signal demodulation device, and the optical fiber hydrophone array module is used for collecting underwater sound wave signals in real time and converting the underwater sound wave signals into first electric signals; the sonar transmitting-receiving array module comprises a broadband sonar transmitter, a multi-beam receiver and a signal preprocessing circuit, and is used for actively transmitting a frequency modulation continuous wave signal, receiving a target reflection echo and generating a second electric signal; and the multi-mode signal fusion processing module comprises a high-speed data acquisition card, a self-adaptive noise suppression unit and a time-frequency analysis unit. The underwater sonar target detection system and method provided by the invention have the advantages of relatively high reliability, relatively high detection performance, relatively accurate cross-modal signal fusion and capability of performing intelligent target identification and tracking.

The present invention discloses a neural network accelerated simulation method for the radar scattering field of a wide-band target group, belonging to the technical field of electromagnetic simulation. The method of the present invention constructs a KAN neural network model at the central frequency of the wide band, and constructs KAN neural network models at other target frequencies through transfer learning or direct training; uses the trained KAN neural network model to generate a multi-frequency point numerical Green's function data set, and then constructs a wide-band training sample to train the multi-task learning model to realize the global prediction of the numerical Green's function of the entire target wide band; uses the numerical Green's function output by the multi-task learning model to realize the fast simulation of the scattering field of the wide-band target group. The method of the present invention can realize the fast and accurate simulation of the radar scattering field of the wide-band target group.

The invention discloses a distribution line broadband waveform sampling method, and belongs to the technical field of power system monitoring. By collecting quantum vacuum fluctuation noise, temperature, humidity and electromagnetic parameters, a quantum environment coupling entropy model is constructed, an optimal sparse base dictionary is dynamically generated, and a noise entropy break variable is calculated. And when the entropy break variable exceeds a threshold value, triggering sub-Nyquist compressed sampling, otherwise, adopting Nyquist rate sampling to realize dynamic matching of sampling resources and signal complexity. A high-frequency component of a compressed signal is reconstructed by combining an adversarial compressed sensing network with a residual network, a low-frequency component is generated based on an original signal, the distribution consistency of high and low frequency entropies is optimized by using a Wasserstein distance, and finally a three-dimensional waveform matrix containing a timestamp, a frequency bin and quantum entropy confidence is output. The problems of low sampling efficiency, poor sparse representation adaptability, slow noise response, inconsistent reconstruction and the like in a non-stationary signal and complex noise environment are solved, and the precision and energy efficiency of broadband waveform sampling are remarkably improved.

A broadband oscillation characteristic identification method for a new energy access AC power grid comprises the following steps: compressing an oscillation signal acquired by a PMU by using a Gaussian random matrix, uploading low-dimensional data to a master station, and reconstructing the signal at the master station through an orthogonal matching pursuit (OMP) algorithm; a VMD algorithm with the minimum energy loss as a threshold value is adopted to conduct self-adaptive decomposition on the reconstructed signals, and IMF components containing oscillation information are obtained; the purpose of blind source separation is achieved by maximizing the non-Gaussian property of the output signal through FastICA, independent components are extracted from the mixed signal, and noise is removed; and finally, calculating related information (frequency and amplitude) of oscillation by using FFT (Fast Fourier Transform). According to the method, the technical advantages of CS-OMP, VMD and FastICA are combined, different kinds of oscillation modes and complex working conditions can be dealt with, broadband oscillation in a power system can be better monitored and recognized, safe and stable operation of a power grid is guaranteed, and accurate characteristic parameters (frequency and amplitude) are provided for the oscillation suppression technology.

Proposed are a method and device for receiving a PPDU in a wireless LAN system. Specifically, a reception STA receives a PPDU through a wide band from a transmission STA, and decodes the PPDU. The wide band is a 320 / 160+160 MHz band configured from a first band and a second band. When the first band is an 80 MHz band in which puncturing is performed in units of 20 MHz, the first band includes a first RU which is an aggregate of a 484RU and a 242RU. The second band is a 240 MHz band excluding the first band in the wide band, and includes a second RU which is an aggregate of three 996 RUs. The PPDU includes a control field and a data field. The data field is received via a first multi-RU which is an aggregate of the first and second RUs.

The present disclosure provides a protective enclosure for electronic systems. The enclosure comprises a polymer-containing matrix and a metamaterial incorporated into the matrix. The metamaterial is tuned to a specific permittivity or permeability to absorb or reflect a particular frequency. The protective enclosure may be used to create a safe inner environment for electronic components while facilitating uninterrupted wireless communications to / from the outer environment. Additionally, the protective enclosure may be used to protect against electromagnetic interference. In particular, shielding metamaterials are configured individually or in combination to specifically shield (via reflection, absorption, etc.) against relatively wide bands of electromagnetic frequencies, while transparent metamaterials are configured specifically to pass electromagnetic signals within narrow bands of frequencies. This new approach resolves and vastly improves current shield solutions, such as Faraday cages. For example, tuned metamaterials may be configured across a variety of preconfigured frequencies, and can be constructed of lightweight materials.

The invention discloses a noise monitoring analysis and fault early warning method and system for a large transformer, and relates to the technical field of noise monitoring, and the method comprises the following steps: collecting and preprocessing a coverage broadband noise signal through a sensor; a CNN-LSTM model is established for the collected noise signals through a deep learning module; and setting an early warning threshold value, performing judgment through the CNN-LSTM model, and triggering an early warning signal. According to the invention, key features can be automatically extracted from transformer noise, real-time analysis is carried out through the deep learning model, multiple fault types can be rapidly identified without manual intervention, early warning can be timely given out, power failure accidents caused by faults are reduced, the stability of power supply is improved, intelligent upgrading of a power equipment monitoring technology is promoted, and the power supply efficiency is improved. And a key technical support is provided for digital and intelligent transformation of the power industry.

The invention provides a broadband low-noise amplifier based on a three-coil coupling transformer. The broadband low-noise amplifier comprises an input matching network, a common-source differential output driving stage amplifier, an inter-stage matching network, a common-source differential output power stage amplifier and an output matching network which are connected in sequence, broadband matching is realized by using the input matching network and the inter-stage matching network, and the effective transconductance of the transistor is improved; through the cross-coupled capacitors, the LNA gain and stability on a broadband are improved, better isolation is realized, and input and output are decoupled; due to the design of the grounding capacitor, the linearity of the LNA is improved; through the combination of the three-coil coupling transformer and the differential topology, output signals are superposed in the same direction at the output end, and noise is cancelled in the reverse direction at the output end, so that the thermal noise is greatly inhibited, the isolation is improved through the output matching network, the insertion loss is reduced, and the output matching performance is optimized.

The invention discloses a broadband high-gain microstrip antenna, which is provided with a rectangular radiation patch, a symmetrical grooving parasitic patch, a dielectric substrate, a metal bottom plate and a polytetrafluoroethylene support column, the rectangular radiation patch and the symmetrical grooving parasitic microstrip are attached to the upper layer of the dielectric substrate; a certain distance is formed between the rectangular radiation patch and the slotted parasitic patch and is used for coupling electromagnetic waves; the upper dielectric substrate is provided with two through holes for feeding; the metal bottom plate and the upper-layer substrate are fixed through four polytetrafluoroethylene supporting columns; a space is reserved in the middle to form an air substrate; and an SMA interface is arranged below the floor. According to the microstrip patch antenna, the forms of differential feeding and parasitic patch adding are adopted, the high gain and broadband characteristics of the microstrip patch antenna are achieved, the profile of the antenna is kept within 0.1 lambda, and the unipolar radiation pattern is achieved while high performance is guaranteed. In addition, the antenna is relatively simple in technical structure and convenient for later processing, can be used as an array unit for arraying, and meets the requirements of modern communication.

The invention belongs to the technical field of antenna engineering, and particularly relates to an ultra-wide-band low-profile phased-array antenna, which realizes broadband impedance matching characteristics and effectively expands the working bandwidth of the antenna by optimizing a dipole arm structure and introducing a matching branch knot and linear tapered slot composite structure on a radiation unit layer; on the array architecture level, an electromagnetic metasurface technology is adopted, array current distribution is improved through a periodic artificial electromagnetic structure, the active standing-wave ratio is remarkably reduced, the scanning angle of an array is widened, and meanwhile high compression of a system profile is achieved; on the structural design level, a three-dimensional composite structure of a transverse metal floor, a longitudinal radiation layer and a transverse metasurface layer is innovatively constructed, and the overall section height is reduced to 0.137 lambda Low (lambda Low is the lowest working frequency wavelength) through electromagnetic coupling and space folding technologies; in conclusion, the ultra wide band (the relative bandwidth is greater than or equal to 90%) and the low profile (lt; and the method is suitable for a new generation of broadband phased array radar system.

The invention provides an oscillator frequency modulation circuit and a communication chip. The oscillator frequency modulation circuit comprises a first resonance area which comprises a first resonance circuit, a first coupling tube (Mn) and a second coupling tube (Mp), wherein the first coupling tube (Mn) and the second coupling tube (Mp) are cross-coupled with the first resonance circuit; the second resonance area comprises a second resonance circuit, and the second resonance circuit comprises a first branch circuit electrically connected with the first coupling tube (Mn) and a second branch circuit electrically connected with the second coupling tube (Mn); the second branch is electrically connected with the second coupling tube (Mp); the first tail inductor (Ln) is connected to the first branch in series; the second tail inductor (Lp) is connected in series with the second branch; and the differential capacitor array (Ct) is connected between the first branch circuit and the second branch circuit in parallel. According to the oscillator frequency modulation circuit and the communication chip, low noise can be realized in a broadband range, the anti-interference capability is realized, meanwhile, the occupied area is relatively small, and high-quality signals can be continuously output for a multi-protocol system.

The invention relates to a broadband planar array antenna light-operated beam forming method based on multi-task sparse learning, and the method comprises the steps: deducing an array factor expression of a broadband array as priori knowledge through employing a rectangular planar array antenna; constructing a multi-frequency-point beam joint optimization model of the planar array antenna based on the neural network; based on the priori knowledge, calculating a total loss function of the model by using expected broadband array pattern data and a group inhaul cable regularization method, and training a multi-frequency-spot beam joint optimization model; and based on the trained model, obtaining the optimal array layout and the amplitude and delay distribution of each array element, and calculating to obtain a low-sidelobe directional diagram in which the deflection angle is irrelevant to the frequency. According to the invention, the deflection angle of the array radiation beam is kept constant in a broadband range, and the problem of'beam squint 'of a traditional phased array is solved; and meanwhile, the beam sidelobe level of each frequency point is effectively suppressed, and the grating lobe problem of the uniform array on the broadband is avoided.

The invention provides a position prediction method and device based on an ultra wide band (UWB) digital key, and a position prediction system applied to the UWB digital key, the position prediction system comprises a UWB tag and a plurality of UWB anchor points arranged on a vehicle, and the position prediction method comprises the following steps: determining whether UWB positioning information of the UWB tag is invalid; when the UWB positioning information is invalid, acquiring a velocity vector and a historical track set of the UWB tag and orientation information of the vehicle; and inputting the velocity vector, the historical trajectory set and the orientation information into a position prediction calculation model to calculate a predicted position of the UWB tag. The technical problem that when an existing automobile digital key is blocked by an obstacle and the digital key cannot be connected to an automobile UWB anchor point, the function of the digital key is in a failure or invalid state, and the user experience is affected is solved.

A vehicle control method is provided for a vehicle having an ultra wide band (UWB) sensor configured to measure a rainfall value. The method includes waking up the UWB sensor in response to a trigger instruction for starting rainfall detection, to cause the UWB sensor to measure a rainfall value; acquiring the rainfall value measured by the UWB sensor; and controlling the vehicle to execute a preset control instruction action according to the rainfall value.

The invention discloses a method and a system for capturing an ultra-wideband navigation signal of a low-orbit satellite, which are used for solving the technical problem that the existing method for capturing the ultra-wideband navigation signal of the low-orbit satellite is easy to cause that the signal cannot be locked, and finally the capturing success rate is low. The method comprises the following steps: acquiring ka-band low-orbit satellite signals and low-orbit satellite pseudo-random noise codes corresponding to a plurality of low-orbit satellite ultra-wideband navigation signals; generating a complex signal and an original intermediate-frequency signal according to a preset sampling rate, preset skipping time and the ka-band low-orbit satellite signal; constructing a pseudo-code spectrum library based on the pseudo-random noise codes of the low-orbit satellites, and outputting the pseudo-code spectrum library; determining a discrete frequency search sequence based on known intermediate frequency parameters of the original intermediate frequency signal, performing matrix construction in combination with the complex signal and the pseudo code spectrum library, and outputting a three-dimensional result matrix; and capturing and judging the ultra-wideband navigation signals of the low-orbit satellites by adopting the three-dimensional result matrix, and determining a plurality of successfully captured ultra-wideband navigation signals of the low-orbit satellites.

The present invention relates to a broadband sound absorption device using area division, the device comprising: Helmholtz resonators including a neck portion and a cavity portion connected to the neck portion and having a predetermined area and thickness; and a unit sound absorber including at least one pair of the Helmholtz resonators, wherein a plurality of unit absorbers are arranged on a plane or curved surface, and the plurality of sound unit absorbers are formed to have cavity portions with different areas to minimize the thickness while enabling sound absorption for a wider band.

The invention discloses a tunable excited Raman spectrum microimaging method and device, and belongs to the field of spectrum detection and optical imaging. The device comprises a broadband adjustable wavelength light source, a high-resolution wavelength scanning module, a stimulated Raman signal excitation module and a stimulated Raman signal detection module. The stimulated Raman signal excitation and imaging module is used for focusing the two beams of narrow-band femtosecond pulse light which are overlapped in time and space on a sample and exciting a stimulated Raman signal, and meanwhile, moving the sample to realize spot scanning microscopic imaging; and the stimulated Raman signal detection module is used for converting the stimulated Raman scattering signal into an electric signal, demodulating the electric signal by using a lock-in amplifier, and recording spectral information by using a data acquisition card. According to the invention, the broadband tunable characteristic of the optical parametric amplifier is utilized to tune the pump light to the wavelength region of the sample absorption peak length so as to realize electron pre-resonance stimulated Raman; and a balance detection technology is combined at a detection end, so that high-sensitivity, high-resolution and high-signal-to-noise-ratio detection of stimulated Raman signals is realized.

The invention provides a frequency, polarization and directional diagram reconfigurable antenna unit and array. The antenna unit comprises a tuning microstrip antenna unit and a reconfigurable feed phase-shift network which are stacked, the tuning microstrip antenna unit comprises a circular radiation patch etched with a circular gap and four variable capacitance diodes bridged on the circular gap; two output ports of a Wilkinson power division network in the reconfigurable feed phase shift network are respectively connected with two feed point micro-strips through PIN diodes, and four feed points form a structure which is in space symmetry and asymmetric in impedance. The circular radiation patch and the annular radiation patch in the antenna unit have continuity in structure, only four variable capacitance diodes are loaded on the annular gap, gain fluctuation is reduced, and the antenna unit is fed through four feed points which are symmetrical in space and asymmetric in impedance, so that the antenna unit is more stable in performance. Good matching can be kept between the feed phase-shifting network and the antenna unit in a broadband range, and the tuning bandwidth of the antenna is widened.

A sensing communication method and device are applied to the technical field of communication. The present application can be applied to a wireless local area network system that supports an IEEE 802.11 ax next generation Wi-Fi protocol (e.g., 802.11 be, Wi-Fi 7, or EHT), or an IEEE 802.11 be next generation Wi-Fi protocol (e.g., Wi-Fi 8, UHR), or Wi-Fi AI, or millimeter wave (mmWave), or ultra wide band (UWB), or sensing. If the first communication device generates the PPDU based on the Q time-varying function values, the PPDU is transmitted. After receiving the PPDU, the second communication device may parse the PPDU based on Q time-varying function values that it agrees with the first communication device. According to the method provided by the embodiment of the invention, the security of information transmission is improved, and the protection of user privacy is effectively realized.

The invention relates to the technical field of high-precision positioning, in particular to a mine tight combination positioning method based on environment self-adaption, and aims to solve the problem of efficient positioning of personnel and equipment in a complex and limited space under a mine. The method comprises the step of acquiring a time difference of arrival measurement value through the ultra-wideband positioning tag and the positioning base station. Chi-square testing is carried out based on the innovation statistics of the extended Kalman filtering, and whether the environment is a sight distance environment is judged according to comparison between the innovation statistics and a threshold value. If the innovation statistic is lower than a threshold value, determining that the environment is a sight distance environment, and if the innovation statistic is higher than or equal to the threshold value, determining that the environment is a non-sight-distance environment. For a sight distance environment, high-precision coordinate estimation is obtained by adopting a time difference of arrival positioning algorithm, and a positioning result is optimized through extended Kalman filtering fusion. And activating the inertial measurement unit, constructing an ultra wide band / inertial measurement unit tight combination extended Kalman filtering model for a non-line-of-sight environment, and outputting a positioning result.

The invention provides a grid-connected inverter impedance detection method based on an L-shaped filter, and belongs to the technical field of grid-connected inverter impedance detection. A multi-frequency-point disturbance signal is injected into a preset grid-connected inverter working point, time domain data of inverter side current and common coupling point voltage are collected, fast Fourier transform analysis is carried out on the collected data, amplitude and phase information corresponding to each injection frequency point is extracted, and a frequency domain feature vector matrix is established; and establishing a frequency compensation matrix model to compensate and correct high-frequency band measurement data based on a frequency characteristic attenuation vector, calculating to obtain optimal estimated values of power grid impedance and grid-connected inverter output impedance, performing error analysis and precision verification on an impedance detection result, and outputting a verified impedance parameter value. The technical problem of insufficient power grid impedance detection precision caused by high-frequency band attenuation of the L-shaped filter is solved.

The invention discloses a non-inductive gate charging distance determination method and device and a storage medium, and relates to the technical field of data processing. According to the method, the sampling distance difference of the mobile terminal is determined based on the sampling distance value of the mobile terminal obtained by sending the ranging signal by the fixed anchor point, then the moving speed of the mobile terminal is determined based on the product of the sampling distance difference and the sending frequency of sending the ranging signal by the fixed anchor point, and the moving speed of the mobile terminal is determined based on the moving speed of the mobile terminal. And determining the charging distance of the gate. Through the method, the ultra wide band non-inductive gate can determine the gate charging distance according to the actual position and the motion state of the user so as to adapt to different moving speeds of the user, and the passing efficiency is improved.

A method of measuring a direction between devices performing ultra-wide band (UWB) communication and each including a plurality of antennas includes transmitting signals through a plurality of antennas by a transmitting device and receiving the signals through a plurality of antennas by a receiving device, and selecting at least one of an angle of departure (AoD) method and an angle of arrival (AoA) method depending on statuses of the transmitting device and the receiving device and measuring the direction between the devices by using a selected method.

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.

The invention belongs to the technical field of quality detection, and discloses an electrical automation quality detection method and system. The method comprises the steps of collecting original voltage and current signals of a PCC point of a power grid and performing FFT to obtain a background harmonic frequency set and a background harmonic amplitude set; generating an initial frequency grid based on a preset target frequency band, and generating a sparse frequency grid in combination with the background harmonic waves; calculating the estimated signal-to-noise ratio of each candidate frequency, performing ascending sorting to obtain an injection sequence, injecting sinusoidal signals, collecting PCC point voltage response and total current, and calculating a frequency impedance data pair; performing rational function fitting based on the frequency impedance data to obtain a broadband impedance curve; analyzing the curve, extracting quality characteristic parameters, and performing quality judgment according to the parameters; according to the method, the technical problem that the grid-connected stability quality of a single new energy converter cannot be quickly and automatically qualified in a production line offline detection scene in the prior art is effectively solved.