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This paper proposes a new multigrid method to efficiently solve the finite element approximation of static or quasi-static electromagnetic problems with quadratic nodal finite elements on unstructured grids in 2D and 3D by using grid information and p-multigrid. Unlike the traditional algebraic multigrid (AMG), the new method constructs the first level coarse grid from the grid information of the...
A hybrid 2D/3D numerical method is introduced to solve the ion flow field around a house near bipolar high voltage direct current (HVDC) transmission lines. At first, a 2D upwind finite element algorithm for the computation on the ion flow field near bipolar line structure is set up. Then a 3D method is used to analyze the ion flow field in the vicinity of a house under the HVDC lines. The 2D results...
This paper proposes a new multigrid method for quadratic finite element method(FEM) by introducing mesh information and p-multigrid. The first level coarse grid is constructed geometrically; the first level restriction and prolongation matrices are built according to the relation of the local basis functions of quadratic and linear FEM. Then, traditional algebraic multigrid(AMG) method is applied...
The corona effect of HVDC transmission lines affects the electromagnetic environment significantly. A numerical method to calculate the ion flow field caused by corona effect in the vicinity of multi-circuit HVDC transmission lines is described. Deutsch assumption, a commonly used simplification in traditional numerical methods is eliminated. Skills of initial value estimation and boundary process...
Since it has a great height, large volume and complicated configuration, the 1000-kV ultra-high voltage surge arrester has a very nonuniform potential distribution, which leads to the depressed service life and low safe reliability. This paper proposed the three-dimensional FEM and circuit analytic method to analyze and improve the potential distribution of the 1000-kV surge arrester. An optimal grading...
In this paper, an upwind finite element (FE) based algorithm devoted for the computation on the ion flow field of bipolar high voltage direct current (HVDC) transmission lines. The choice of initial charge density value on conductor surface is discussed to satisfy the requirement of bundle conductor computation. Non-reflective boundary condition is introduced to improve the computational efficiency...
The metal oxide arrester (MOA) is key equipment in high voltage power system. If the potential exerted on a ZnO disc is very high, it is more easily destroyed than others. Compared with GIS MOAs for 750 kV and below, the 1000 kV GIS MOA has greater height, larger volume and multiple columns, which leads to a very nonuniform potential distribution and makes the method to analyze the potential distribution...
A numerical method to calculate the ion flow field in the vicinity of multi-circuit DC transmission lines is described. Details of the transmission lines such as bundle conductors and ground wires are taken into account in this simulation model. Deutsch assumption, a commonly used simplification in traditional numerical methods is eliminated. The ion flow field of a ??500 kV HVDC project with bipolar...
In this paper, a method is presented to extract the per-unit-length inductance matrix L for closely separated multiconductor transmission lines having conductors with any kind of cross sections over a finitely conducting ground in frequency domain. First, the L over a perfect conducting ground is obtained from the per-unit-length capacitance matrix C by using finite element method. Then the effect...
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