The Lightning Protection Of Buildings Or Structures Of Different Materials Modeling Research

With the increasing emergence of high-rise buildings and structures, especially those intelligent structures, due to the rapid development of economy and modernization, more and more serious hazards and indirect heavy economic losses are arising from lightning disturbance and influence society greatly. Therefore, in order to cut down such big losses it is really necessary to conduct the research of stroke-incidence rate and take effective measures to protect buildings and structures against lightning.This thesis is composed of three parts. Part One provides an analysis of the lightning incidence, mainly arguing the cause of lightning trouble and introducing some general principles as well as measures taking to protect structures against lightning.In Part Two, thundercloud pre-stroke electrostatic model and transmission line model (TL for Transmission Line) are established so as to simulate the distribution of lightning electromagnetic field. According to the mathematical model of lightning electromagnetic field, different curves that reflect the distribution of lightning electromagnetic field can be easily obtained by means of the programming and the calculating under the MATLAB. On the basis of the above results, the author analyses the way the lightning electromagnetic field protects structures against lightning and then points out some characteristic features of lightningelectromagnetic, including lightning electromagnetic field in the process pre-stroke, as well as the features of LEMP (lightning electromagnetic pulse) when lightning discharge occurs through a conductor. Thus, the theoretical and the technical basis of the new view on lightning protection is achieved.In Part Three, in the light of the fundamental theory of electrostatic field and from the perspective of atmospheric electricity, the author puts forwards the lightning protection models according to different features of high-rise buildings and structures, which are made up of various materials, in the lightning electromagnetic field. Furthermore, with the help of the basic theory of lightning protection and with the reference to the designing standardization of buildings together with the calculation results of the lightning electromagnetic field, the author makes a further study on lightning protection model of building and structures and analyzes the reason of stroke-incidence. Based on the above analysis, measures to improve the protection of structures against lightning are secured. In conclusion, the author brings forward a new view on the direction of the research of the protection ofstructure against lightning as well as on the developing trend of it.LI Xuewen (Power electronics and electrical drive)Directed by Sun Keping...