8 results about "Harmonic fields" patented technology

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.

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 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 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.