Surface voltages and resistance of grounding systems of grid and rods in two-layer earth by the rapid Galerkin's moment method

A new mathematical model for accurately computing currents flowing along the high-voltage ac substation's grounding system and nearby floating metallic conductors buried in the multilayer earth model has been developed in this paper, which is a hybrid of the Galerkin-type boundary element method (BEM) and the conventional nodal analysis method. Only the propagation effect of electromagnetic waves within the substation's limited area has been neglected in this model. The quasi-static complex image method and the closed form of Green's function are introduced into this model to accelerate the mutual impedance and induction coefficients calculation. The model is then implemented in a computer program, which can be used to calculate current distribution of any configuration of the grounding system, with or without floating metallic conductors'.

“…The first case comes from [12], which is based on electrostatic field theory and the equalpotential model. Figure 5 shows a grid with nine rods.…”

Section: Verification Of the Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Numerical calculation of grounding system in low‐frequency domain based on the boundary element method

Fan²

2007

“…The performance of an a.c. substation grounding system under low frequency, 50 or 60 Hz are always analysed based on the analogy electrostatic field (or direct current electrical field) theory [1][2][3][4][5][6] in recent years.…”

Section: Introductionmentioning

confidence: 99%

Numerical simulation of substation grounding grids buried in both horizontal and vertical multilayer earth model

Fan²,

Chen

2006

SUMMARYIn the simulation of quasi-static electromagnetic fields produced by a point source located in both horizontal and vertical multilayer media, the conventional image method requires an infinite number of images to get an accurate solution, while the method of quasi-static complex images needs only a few ones. Based on the method of quasi-static complex images, the closed form of Green's function of a point source in both horizontal and vertical multilayer earth model is derived through matrix pencil (MP) approach. The fast convergent Galerkin's type of boundary element method (BEM) is taken to simulate and analyse a grounding system including floating electrode with any complicated structure, which can be located anywhere in horizontal or vertical multilayer earth model.

“…By introducing the discretization described in (8) for each of the element on PEC/DM interface (4) can be written as (10) where N T is the total number of triangles, N el is the number of triangles on PEC/DM interfaces, V e is the value of the potential on the electrode on which the mth element lies and S m,n is the coefficient given by…”

mentioning

confidence: 99%

3D source simulation method for static fields in inhomogeneous media

Canova

Gruosso

2006

SUMMARYIn this paper, an integral approach based on the source simulation method (SSM) for the solution of three dimensional (3D) static electric fields is presented. This is an extension of the well-known charge simulation method to the electric and current static fields. The formulation allows the solution of 3D electrostatic or static current field problems, where several perfectly conducting bodies (electrodes) are placed in inhomogeneous media. Only electrode surfaces and dielectric interfaces need to be discretized by triangular elements. Matrix coefficients are accurately evaluated by using closed integral forms of 1/r and of grad(1/r ). Dirichlet and Neumann conditions can be imposed on the different conducting bodies; in particular, floating potential problem can also be solved. The method of images allows ground plane to be taken into account. The procedure has been applied to several practical cases and it represents an efficient tool for the evaluation of lumped circuit parameters such as capacitances of 3D conducting bodies and ground resistances of grounding systems.