17 results about "Matrix pencil" patented technology

The invention provides a TOF (Time of Flight) estimation method of a matrix bundle based on partitioning and random SVD (Singular Value Decomposition). The method comprises the following steps: firstly, acquiring channel state information (CSI) by using a commercial WiFi device, and constructing a CSI matrix; and secondly, performing block overlapping processing on the CSI matrix, constructing an augmented matrix for each CSI data block, and performing SVD decomposition on the augmented matrix, thereby reducing the calculation complexity of SVD decomposition. And then, the time of flight (TOF) of each CSI data block is estimated by using a matrix pencil algorithm, and the minimum TOF is direct path estimation. According to the method designed by the invention, the robustness of the system and the estimation precision of the TOF are improved under the condition that the algorithm complexity is greatly reduced.

The invention discloses a method for extracting characteristic parameters of a low-frequency oscillation mode of a power system, and in the power system, a time sequence signal generally refers to records of parameters such as voltage, frequency and the like in the system along with time change. In order to effectively analyze the signals, singular spectrum analysis is firstly carried out, the singular spectrum analysis comprises the steps of converting the time sequence signals into a track matrix, then carrying out singular value decomposition on the track matrix, and reconstructing a time empirical orthogonal function obtained after singular value matrix decomposition, and at the moment, a denoised reconstructed signal is obtained; and performing matrix pencil analysis on the reconstructed signal, and extracting characteristic parameters of the low-frequency oscillation mode. In this way, the characteristic parameters of the low-frequency oscillation mode can be accurately extracted under the condition that the identification integrity is guaranteed.

The invention provides a self-adaptive restart method for an extra-high voltage direct current transmission system containing a hybrid MMC, and the method comprises the steps: analyzing the attenuation characteristic difference of a system current aperiodic component under different fault properties through building an equivalent model of a power grid commutation converter (LCC) station and a hybrid MMC station in a restart stage; and a matrix pencil algorithm (MPM) is adopted to extract a non-periodic component to construct a fault property identification criterion, so that a self-adaptive restart strategy is formed. The strategy can sensitively and reliably identify an instantaneous fault and a high-resistance permanent fault on the premise of not depending on communication, the restart success rate of the system is effectively improved, and the operation reliability of the system is enhanced. The method is suitable for a hybrid direct current system and a pure flexible direct current system, and has remarkable technical advantages and application value.

The present invention discloses a method and system for identifying power system oscillation parameters based on synchronized phasor data, which relates to the technical field of power system oscillation analysis. It solves the problem that the traditional MPM directly obtains the eigenvalues of the matrix pencil, resulting in large errors. The key points of its technical solution are as follows: By constructing a real Hankel matrix and solving the eigenvalues of this matrix, the fundamental wave component angular frequency that satisfies the angular frequency conjugate constraint of two modes of the fundamental frequency component and the oscillation component angular frequency that satisfies the angular frequency conjugate constraint of two modes of the oscillation component can be directly obtained. The solution is simple and the computational amount is small. Moreover, by combining the real part and the imaginary part of the synchronized phasor to construct a real Hankel matrix, the information of the synchronized phasor can be completely retained, and thus the subsynchronous oscillation parameters can be accurately identified under an ultra-short data window.

The invention relates to the technical field of power system monitoring, in particular to a higher harmonic and inter-harmonic measurement method and system based on an improved matrix bunch, and the method comprises the steps: firstly receiving a synchronous phasor data sequence of a power system, and constructing an L * P Hankel matrix Y; carrying out SVD (Singular Value Decomposition) on the Hankel matrix Y; constructing a matrix bundle based on a total least square framework, and solving a system matrix; and conjugate symmetry physical constraint is applied to a solution result, and oscillation modal parameters including frequency, damping ratio and amplitude are extracted, so that the inherent defects of low precision, limited resolution and incapability of analyzing attenuation dynamics when low-frequency higher harmonics, inter-harmonics and attenuation harmonics are measured in the prior art are solved, and the method is suitable for the measurement of the low-frequency higher harmonics, inter-harmonics and attenuation harmonics. And harsh requirements of a modern intelligent power grid on high-precision monitoring and analysis of the electric energy quality are difficult to meet.

The present invention provides a method for reconstructing the direction pattern of an opportunistic array radar for a dynamic multi-node platform, including: initializing task objectives and constraint condition parameters; selecting fuzzy numbers according to requirements and establishing a fuzzy chance-constrained programming model for reconstructing the direction pattern of the dynamic multi-node opportunistic array radar; and solving the model by using the matrix pencil method combined with fuzzy simulation for multi-plane array approximation. The general model and solution method constructed by the present invention can establish corresponding programming models under different task requirements, effectively solve the problem of system robustness caused by the influence of the dynamic environment involved in the direction pattern reconstruction problem in practical applications, and the node resources and position information of the opportunistic array radar can be dynamically adjusted according to the environment tasks, which is more in line with practical applications, realizes the adaptability of the opportunistic array radar, that is, the characteristic of adjusting system parameters according to different task requirements, and provides a reference for modeling and solving other problems related to the opportunistic array radar.

The invention discloses a pilot protection method and system based on current model identification, and the method comprises the steps: respectively building a mathematical model of the sum difference ratio of fault component current at two ends when external faults occur at the m side and n side of a line; defining an n-side external fault model error function, and when an n-side external fault occurs, En = 0; extracting a frequency point and a complex amplitude of the fault current by using a least square matrix pencil algorithm, and solving system inductances Lm and Ln on line; reconstructing an error function based on the system inductances Lm and Ln, generating a fault feature model, defining a model unbalanced current of an ith frequency component, combining an attenuation direct current component and two harmonic components of the lowest frequency to a set omega, and calculating the sum of the unbalanced current to obtain transient energy of fault current; and respectively defining an n-side external fault dynamic error function En and an m-side external fault dynamic error function based on the transient energy of the fault current, and when the En simultaneously exceeds a preset action threshold, determining an internal fault and triggering a protection action.

The present application provides a broadband elevation - azimuth joint estimation method and apparatus based on a low - complexity atomic norm minimization method. The method includes: performing a fast Fourier transform on the data received by a uniform rectangular array to convert the signal into a multi - frequency form; obtaining a second - order Toeplitz matrix containing elevation angle and azimuth angle information through a reduced - scale atomic norm minimization algorithm; estimating the spatial angular frequency from the second - order Toeplitz matrix using matrix pencil matching; and converting the estimated spatial angular frequency into an elevation angle and an azimuth angle. The advantages of the present application are as follows: it can achieve DOA estimation in the case of small samples with higher efficiency; it eliminates the influence of grid mismatch; the accuracy is greatly improved; the calculation results are highly accurate; it is more in line with the actual situation and has a wider applicability.

This invention discloses a forward-looking multi-channel SAR motion error compensation method based on PGA and matrix beaming, applied in the field of radar technology. It addresses the problems of existing technologies where compensation effectiveness is highly dependent on navigation equipment accuracy and fails to fully compensate for two-dimensional spatially varying phase and linear error components. This invention obtains RD-domain imaging results by performing deskewing and Fourier transform on the echo with phase error after range compression and migration correction. Then, rootmusic angle measurement is performed on overlapping targets in the RD-domain imaging results, equating the deblurring problem to solving a linear inverse problem, resulting in an optimization problem. Solving the optimization problem yields unblurred RD-domain echoes. The PGA algorithm is then used to estimate higher-order errors in the deblurred echoes. The matrix beaming algorithm is then used to estimate residual linear errors. Finally, the estimated motion error terms are incorporated into the coherent accumulation process to obtain the motion error-compensated imaging result.

The invention discloses a power network oscillation analysis method and system considering line distribution characteristics, and the method comprises the steps: building a generalized state space model based on a matrix pencil based on the related parameters of lumped parameter transmission equipment, and building a time-delay algebraic equation set based on the obtained related parameters of a distribution parameter line; converting the time-delay algebraic equation set into a finite-dimensional differential equation set by adopting a spectral discretization method; forming a free oscillation model of the passive power network by using the Kirchhoff's law, and determining a forced oscillation model of the passive power network under the ideal excitation source; performing generalized eigenvalue decomposition, identifying a key resonance mode, solving a forced oscillation model of the passive power network under an ideal excitation source, and obtaining right and left eigenvectors corresponding to dynamic characteristics of the power network; and analyzing the obtained right and left feature vectors corresponding to the dynamic characteristics of the power network, determining harmonic voltage distribution of each bus of the power network and a weak area susceptible to harmonic waves, drawing a harmonic distribution diagram, and outputting an identified key resonance mode.

The invention discloses a standard determination method for a decentralized bottom pool robust mechanism based on a block chain, and the method comprises the following steps: collecting bottom pool operation data, and carrying out the authenticity verification, and obtaining verification data; registering a judgment standard template and a threshold parameter; basic indexes are calculated according to the verified data, and an initial index set is obtained; performing denoising and unification processing on the initial index set to generate a to-be-judged index sequence; executing a multi-fractal detrending fluctuation analysis operation on the to-be-judged index sequence to obtain a fluctuation characteristic result; performing matrix pencil method decomposition operation on the to-be-determined index sequence to obtain inherent fluidity modal characteristics; combining the fluctuation feature result and the modal feature result with the to-be-judged index sequence to generate a standard judgment result and confidence; and writing the standard judgment result and the confidence into a block chain account book, and executing risk prompt and governance proposal. According to the method, the standard judgment of the decentralized bottom pool is realized.

The invention belongs to the technical field of energy storage converters, and particularly relates to a subsynchronous oscillation active suppression method of an energy storage converter. According to the method, on the basis of the time domain modal decomposition principle of a signal, sliding window framing is carried out on a sampling current, a Hankel matrix is constructed, a complex modal pole of the signal is extracted by adopting a matrix pencil method, and the frequency, amplitude and phase of each subsynchronous oscillation component are identified in real time. On the basis, according to an identification result, a multi-mode superposed anti-phase compensation current signal is constructed and injected into a converter control link, active counteracting of subsynchronous oscillation energy is achieved, and therefore damping and stability of the system are improved. By means of the method, the subsynchronous oscillation mode in the power grid can be identified in real time, the suppression current instruction is generated, and self-adaptive active subsynchronous oscillation suppression of the converter is achieved.

The invention belongs to the technical field of power system automation, and discloses a power distribution network fault positioning method and system based on traveling wave modal time delay and path characteristic frequency analysis. The method comprises the following steps: firstly, acquiring a fault transient voltage signal through single-ended measurement, and preliminarily estimating a fault distance by utilizing a propagation delay inequality between an alpha-mode component and a zero-mode component of the fault transient voltage signal; then, aiming at a plurality of possible fault positions corresponding to the distance in the network topology, adopting a matrix pencil method to carry out high-resolution spectral analysis on the signal, and extracting a characteristic frequency related to a fault path; and finally, accurately identifying the position of the fault by comparing and analyzing the extracted actual frequency and the theoretical frequency of each candidate path and combining the residual amplitude. The method has the advantages of being high in anti-noise capacity, free of synchronous measurement and high in calculation efficiency, and high-precision and high-robustness fault positioning is achieved in the complex branch power distribution network.

The invention discloses a high-frequency-resolution dynamic broadband measurement method, and belongs to the technical field of broadband measurement of a power system. The invention relates to a high-frequency resolution dynamic broadband measurement method, which comprises the following steps of: carrying out discrete sampling on broadband voltage and current electrical quantities of a power system to obtain a discrete sampling value sequence; carrying out all-phase FFT (Fast Fourier Transform) on the discrete sampling value sequence to obtain an all-phase amplitude-frequency spectrum and a phase-frequency spectrum; the spectrum peak of the amplitude frequency spectrum is searched, and broadband component characteristics are identified according to the phase of the phase frequency spectrum corresponding to the three spectrum lines with the maximum amplitudes; the frequency and the amplitude of the static non-dense component are corrected through a three-spectrum ratio method; dense components are distinguished through a matrix pencil method; and calculating the frequency, the amplitude and the phase angle of the dynamic component through a second-order Taylor expansion model. By adopting the high-frequency-resolution dynamic broadband measurement method provided by the invention, the amplitude, frequency and phase angle parameters of broadband voltage and current electrical quantity with time-varying and multi-component superposition parameters can be accurately measured in real time.

The invention discloses a new energy station sending-out line protection method and system based on current model identification. A fault component network is adopted to avoid the influence of the system operation state. Errors caused by a line distributed capacitance model can be eliminated by constructing a mathematical model based on a Bergeron model. Multi-frequency quantity information in a transient process can be effectively extracted by using a matrix pencil algorithm; setting calculation can be simplified by calculating system model parameters through power frequency quantity information, and meanwhile the protection method can adapt to various types of power sources; and the model error is calculated by using the non-power-frequency transient quantity, so that the rapid action of protection can be realized.

This invention proposes an FTM-corrected non-line-of-sight ranging method based on matrix-bundled CSI multipath parameter estimation. First, Channel State Information (CSI) data from WiFi devices is collected, an augmented matrix is ​​constructed, and singular value decomposition is performed to obtain a left singular matrix and singular value vectors. Second, the average power of the CSI is calculated and transformed to the logarithmic domain to determine the maximum number of candidate paths. Based on the singular value vectors, a Minimum Description Length (MDL) criterion is constructed to adaptively estimate the number of effective paths. Then, the propagation delay of each path is obtained using the matrix-bundled algorithm, a Vandermonde matrix is ​​constructed, and the received power of each path is estimated using the least squares method. Finally, the power ratio of the direct path is calculated as a reliability factor. If it is below a threshold, the second strongest path is selected from the reflection paths with power greater than the direct path. If there is only one such path, it is selected. The average delay difference between the reflection path and the direct path is calculated using power weighting, and this delay difference is used to compensate for the FTM receiving timestamp to obtain the corrected ranging distance. This invention does not require a preset number of paths, is highly adaptive, and significantly improves the accuracy of FTM ranging in non-line-of-sight environments.

The application discloses a highway section vehicle variable speed limit real-time adjustment method and system based on big data, which comprises a face recognition device, a weather detector, a traffic flow detection device, a control center and a variable speed limit display board. According to the driving characteristics of the driver, the current weather quality data and the traffic parameters, a SEM measurement model is constructed, a constraint expression of the latent variable and the manifest variable of the measurement model is established, the driving characteristics, the current weather quality data and the traffic flow parameter data set are normalized and pretreated by using a MinMax scaler, high-dimensional matrix blocks are divided into low-dimensional matrix sets based on a matrix pencil algorithm, and a characteristic matrix is obtained J by constructing the data set J , the characteristic matrix is integrated and solved with the highway section speed limit vehicle speed, and a real-time adjustment vehicle speed is obtained. The application can combine the matrix big data algorithm to realize real-time adjustment control of the fixed speed limit value of the highway section, improve the dynamic ability, realize the variable speed limit in a personalized manner and improve the driving safety.