Simulação computacional de descargas atmosfericas em estruturas de proteção visando analises de compatibilidade eletromagnetica
AUTOR(ES)
Geraldo Peres Caixeta
DATA DE PUBLICAÇÃO
2000
RESUMO
This work presents the study of protection against lightning through current transitory coniputational simulation and electromagnetic field results. The development of a new ana1ytical expression of calculation for the electromagnetic field was necessary (in Cartesian coordinates) due to the generality of the possible configurations of a structure. The process of simulation is composed of four phases, which were included in the same computer program, written in the Fortran language. In the first phase, the lightning return current Was modeled as a transmission line arranged in the vertical axis, connecting the source (cloud) to the earth (or to a protection structure). In the second phase, the protection structure was modeled as cables interconnected in any geometry, connected to the lightning channel and then to the ground mesh. In the third phase, the ground mesh Was also modeled as interconnected cables. In the last phase, the electromagnetic field calcuIation expression of the transitory of current of the whole process mentioned Was applied. In the simulation of the expression of the field calculation each segment ofthe cables (or lines) was considered as small dipoles and the image method was adopted. Transmission Line Modeling TLM showed to be the best option in the current transitory simulation, once for each cable (considered as a transmission tine), which pennitted the adoption of that technique in one dimension. This artífice canoot be used in other numeric techniques, for example in the tinite differences method. In tinite elements, or the Moment method, the discretization of alI the space is necessary, although problems of contour conditions occur. In the simulation of the electromagnetic field, the tinite differences were adopted with a new developed expression. The advantage of this solution is to work with the analytical expressions and the fact oí not having to completely discretize the space around the simulated system.
ASSUNTO(S)
campos eletromagneticos interferencia eletromagnetica raio calculos numericos - programas de computador transitorios (eletricidade) sistemas de energia - proteção compatibilidade eletromagnetica
ACESSO AO ARTIGO
http://libdigi.unicamp.br/document/?code=vtls000238366Documentos Relacionados
- EMC aspects in strcutures directly struck by lightning.
- Desenvolvimento de um programa computacional visando o estudo das tensões induzidas por descargas atmosfericas
- Projeto de sistema de proteção de edificações contra descargas atmosféricas assistido por computador
- Uma contriduição ao estudo da proteção de redes eletricas contra tensões induzidas por descargas atmosfericas
- Simulação computacional de medidas estereológicas em estruturas de metal duro (WC-Co)