14 results about "Harmonic fields" patented technology

The invention discloses a low-frequency time-harmonic multi-component electromagnetic detection method, and particularly relates to the technical field of geophysical exploration, and the method comprises the steps: S1, transmitting an excitation signal; s2, receiving a signal; s3, signal processing; and S4, conversion imaging. The low-frequency time-harmonic field technology is adopted, the limitation that the detection depth of a traditional ground penetrating radar is small is broken through, the detection depth can reach 0-100 m, the requirement for urban deep underground space detection can be met, the detection depth is large, through collection of multi-component electromagnetic signals and processing of an intelligent inversion algorithm, the geometric parameters of a deep stratum underground target body can be inverted, and the detection accuracy of the ground penetrating radar is improved. The method has the advantages that the resolution is higher than 5% of the depth, fine detection of an underground target body is achieved, the resolution is high, the phase alternating emission technology, the data accumulation averaging technology, the ultra-low noise amplification technology and the like are adopted, base value deviation, external interference signals and noise of a measurement system are effectively restrained, the signal-to-noise ratio and stability of the system are improved, and the anti-jamming capability is high.

The invention discloses a partial discharge harmonic online early warning method for a cable branch box, and particularly relates to the technical field of electrical measurement and power equipment state monitoring. And a unified time base is difficult to obtain through multi-point monitoring, harmonic distortion is easy to be misjudged as discharge, and stable positioning is difficult in a topological constraint. Harmonic scene fingerprints are constructed under a unified time base, version locking is carried out, power frequency phases are re-calibrated according to the fingerprints, gating compensation is set in a non-whole frequency band domain, and joint matching is carried out by combining arrival time difference with energy attenuation under the constraint of a topological equivalent transmission matrix. And dual-threshold interlocking trigger early warning is carried out by combining the separation degree with topological consistency, so that partial discharge pulses can still be stably displayed under the change of a harmonic working condition, false alarm and caliber drift caused by harmonic waves are inhibited, reviewable positioning and executable graded early warning of branch and joint levels are realized, and the reliability of the system is improved. And the stability, comparability and implementability of field judgment are improved.

This invention proposes a multi-frequency electromagnetic feature fusion method for abrasive particle identification, involving signal processing, sensor information fusion, and intelligent monitoring of mechanical conditions. It solves the problems of measurement distortion caused by hardware parasitic parameter coupling, the inability to directly solve the highly nonlinear time-harmonic field model analytically, and the poor convergence of conventional optimization algorithms leading to misjudgment of abrasive particle parameters in existing abrasive particle identification methods. This invention constructs a forward analytical model of the time-harmonic field and a nonlinear objective function, and utilizes the Levenberg-Marquardt (LM) optimization algorithm to jointly invert and extract the equivalent diameter, conductivity, and relative permeability of unknown metallic abrasive particles in a multi-dimensional parameter space. This invention can accurately decouple the equivalent diameter, conductivity, and permeability of abrasive particles, accurately distinguish materials, and the LM algorithm converges quickly and does not diverge, achieving millisecond-level inversion, meeting the high precision and real-time requirements of online monitoring of industrial oil.

The present application discloses a time-harmonic field excitation equivalent method based on loss and temperature distribution and related devices, which relates to the field of transformers, and includes: obtaining the total core loss of a target transformer when a set excitation voltage is applied and a set DC bias current is injected, using the total core loss as the target value, determining an equivalent power frequency excitation voltage when the set excitation voltage and the set DC bias current are equivalently converted to the case without DC bias based on the principle of consistent core loss, and calculating the loss distribution and temperature distribution of the core in the target transformer in a time-harmonic field finite element simulation software according to the equivalent power frequency excitation voltage. The present application can, based on the principle of consistent core loss, equivalently convert the set excitation voltage and the set DC bias current under the condition of DC bias into an equivalent power frequency excitation voltage without DC bias, so that the present application can be calculated in a time-harmonic field finite element simulation software, with shorter time consumption, lower resource consumption and greatly improved simulation calculation efficiency.

This application discloses a time-harmonic field excitation equivalent method and related apparatus based on transformer load loss, relating to the field of transformers. The method includes: obtaining the equivalent excitation current of the target transformer under DC bias conditions; calculating the equivalent inductance component of the excitation current at power frequency based on the principle of conservation of magnetic field energy; calculating the equivalent resistance component of the excitation current at power frequency based on the principle of conservation of ohmic and eddy current losses; and calculating the load loss and structural component temperature rise of the target transformer in time-harmonic field finite element simulation software based on the equivalent inductance and resistance components of the current. Therefore, this application uses load loss as the equivalent basis, equating the excitation current to the equivalent inductance and resistance components at power frequency, enabling the calculation of structural component temperature rise in time-harmonic field finite element simulation software, which is more time-saving, labor-saving, and convergent, while also reducing resource consumption.

The present application belongs to the field of harmonic processing, and provides a converter adaptive harmonic suppression method and system under a complex background harmonic scene, which compensates for the grid modulation voltage by using a method for voltage source type background harmonics, quickly identifies the background harmonics in the grid-connected current based on a method for current source type background harmonics, quickly identifies the optimal compensation phase and optimal compensation amplitude of the harmonic component exceeding the threshold, and compensates for the converter current reference instruction. The present application realizes efficient management of power quality problems in the complex scene of comprehensive voltage source type and current source type background harmonics.

The present invention belongs to the field of digital stomatology, and in particular relates to a method for tooth and jaw segmentation based on optimal seed points of harmonic field scalar intensity, which can quickly and accurately find the gingival margin line on the tooth and jaw 3D model. The steps include: picking feature points on each tooth 3D model in the tooth and jaw 3D model. Constructing a segmentation domain for each tooth 3D model, and constructing a harmonic field within the segmentation domain, and assigning scalar values ​​to mesh vertices through the harmonic field. Screening is performed based on the scalar values ​​of the mesh vertices to obtain an initial screening area and a final screening area, and the final screening area is clustered to obtain a class area. Interpolating the one-ring neighborhood edges of the mesh vertices in the initial screening area, and adding the interpolation points to the corresponding sets according to the scalar values. Based on the one-ring neighborhood vertices of the mesh vertices in the class area and the scalar values ​​of the interpolation points, the scalar intensity of the mesh vertices in the class area is calculated, and the optimal seed point is obtained. The tooth gingival margin line is extracted based on the optimal seed point and the tooth and jaw segmentation is completed.

The application provides a finite element grid deformation electromagnetic simulation method based on harmonic field gradient lines, which comprises the following steps: step 1, taking the grid of an electromagnetic structure before deformation as an initial grid; step 2, defining three types of boundaries according to the deformation of the electromagnetic device geometric boundary and the movement of the grid nodes on the geometric boundary; step 3, establishing a boundary value problem of a harmonic field described by a Laplace equation; step 4, drawing gradient lines passing through each grid node by using the distribution of the obtained scalar field u; step 5, obtaining a new position P2' of a P2 point after deformation according to the property that the relative position of the P2 point is unchanged, performing linear mapping on the gradient lines, and obtaining the gradient lines after deformation with P2' and P3 as end points; step 6, weighting the displacement of the end points of the gradient lines according to the linear mapping relationship and the proportion of the P1 point in dividing the gradient lines, so as to obtain the displacement of the grid node P1; and step 7, moving the grid nodes on the slip boundary Γ d . s ​

The invention discloses an electromagnetic sensor signal analysis method and system based on real abrasive particle dynamic trajectory and time-harmonic field intensity coupling, and belongs to the field of mechanical equipment state monitoring and sensor simulation. The method comprises the following steps: firstly, based on a CFD-DEM coupling theory, combining abrasive particle multi-physical field stress, and accurately reconstructing a real three-dimensional dynamic track in a complex flow field of a lubricating oil pipeline; and establishing a three-dimensional time-harmonic magnetic field analysis model based on magnetic vector potential and a modified Bessel function, constructing a dynamic mapping relation between the transient position of the abrasive particles and a non-uniform magnetic field, quantifying the disturbance characteristic of the abrasive particle eddy current to the magnetic field, and solving the transient response of the sensor induced electromotive force. Abrasive particle size, material conductivity and magnetic conductivity parameter correction are fused, simulation distortion caused by a simplified motion model and neglect of radial magnetic field difference in a traditional theory is overcome, and high-precision prediction of dynamic signals of the whole process that the abrasive particles pass through the sensor is achieved. The method is suitable for health monitoring of aero-engines and industrial gearboxes.

The invention discloses a multi-mode compression analysis method based on a lithium niobate micro-ring resonant cavity second-order frequency comb, and the method constructs a second-order frequency comb generation model, the model is based on an MATLAB simulation environment, and is used for simulating and representing the evolution process of the second-order frequency comb based on the structure of a micro-ring resonant cavity. Wherein a second-order coupling average field theoretical model containing interaction of a pumping field and a semi-harmonic field is adopted in simulation; and carrying out multi-mode compression degree calculation and super-mode decomposition coefficient distribution analysis on the generated second-order frequency comb by adopting an analytic Bloch-Mapse decomposition algorithm so as to quantitatively evaluate the quantum compression characteristic and mode coupling rule of the frequency comb. The invention lays a key technical foundation for the application of the lithium niobate micro-ring resonant cavity in the fields of quantum optics, optical communication and the like.

The application discloses a kind of phase perfect matching high-efficiency second harmonic generation efficiency nonlinear optical structure, including fundamental wave resonant structure, nonlinear optical layer, second harmonic reflection structure and substrate;Fundamental wave resonant structure is used to generate electromagnetic field local enhancement at incident fundamental wavelength, and phase matching condition is realized by optimizing electric field phase distribution;Nonlinear optical layer is used for frequency conversion of fundamental wave to second harmonic, and harmonic radiation capacity and phase control are regulated;Second harmonic reflection structure is used to control the coupling-out of second harmonic;Rotating nonlinear optical layer can adjust the phase characteristics of radiated second harmonic, to realize the phase perfect matching of harmonic field;The phase perfect matching high-efficiency second harmonic generation efficiency nonlinear optical structure realizes the accurate control of phase matching condition by reasonable optical thin film stack and phase matching technology, ensures the efficient coupling-out and utilization of second harmonic.

The invention discloses a tooth segmentation method and system and computer equipment, and relates to the technical field of digital oral cavity, and the method comprises the following steps: obtaining a tooth local area on a 3D dental grid model; constructing a depression sensing harmonic field in the tooth local area, and calculating scalar intensity of grid vertexes in the tooth local area through the depression sensing harmonic field; optimal seed points located on the segmentation boundary are screened out according to the scalar intensity; according to the optimal seed point, a path search algorithm is adopted to extract a segmentation boundary; segmenting the teeth based on the segmentation boundary; the method can realize accurate and efficient tooth segmentation, has relatively high stability and robustness, and can meet clinical requirements.

The invention relates to the technical field of spacecraft structure design and manufacturing integration, in particular to a man-machine collaborative spaceflight design method, which comprises the following steps of: constructing a design contract and a design hypergraph, and optimizing configuration parameters in a microphysical model; an accessibility cone field and a flutter critical frequency field are obtained through analytic geometry and dynamic modes, and a feasibility certificate is generated through square sum form verification; executing continuous relaxation planning and constraint projection based on a type system on the process resource hypergraph, and generating a safe trajectory and a measurement path by combining a control barrier function and a harmonic field; and gathering into a patch based on the minimum hit of the counter-example set, writing back, and triggering local resolution and reverification. According to the invention, consistent convergence of contract satisfaction, manufacturing feasibility and evidence auditing is realized.