Experimental Simulation Study On Radiation,Coupling And Suppression Method Of Lightning Electromagnetic

The research on the system of lightning electromagnetic radiation,coupling mechanism and suppression method is very important for the research of lightning detection,lightning warning and forecasting.On the other hand,it is effective to suppress the lightning electromagnetic pulse,Mine business work to provide a smooth guarantee.Based on this,the internal temperature characteristics of the lightning channel and the radiation and coupling of the electromagnetic wave of the channel are studied deeply and the corresponding suppression method is put forward.The main contents and conclusions of the paper are as follows:(1)Through the establishment of lightning antenna model and cable to receive lightning electromagnetic pulse test model,the use of lightning shock platform for the 8/20?s impact current to simulate the lightning current,the use of antenna,twisted pair and coaxial coupling simulation lightning channel The relationship between the peak value of the overvoltage,the magnitude of the energy and the impulse voltage of the radiation source,the distance between the receiving end and the radiation source,and the distance between the receiving end and the distance from the radiation source are analyzed.The center frequency of the antenna and other factors related to the antenna in the coupling of lightning electromagnetic pulse signal process will be missing and other laws;summed up the twisted pair and coaxial line coupling lightning electromagnetic pulse voltage and spectral characteristics of the cable with the impact of the process In the voltage amplitude and energy absorption of the law of change.(2)The atomic spectrum theory and the local thermodynamic equilibrium(LTE)model were applied to the study of the lightning spectrum.The lightning energy was simulated by the lightning impulse platform.The spectral energy of the infrared band spectrum(930nm)and the visible spectrum(648.2nm)It is concluded that the peak of the luminous intensity of the infrared band and the visible band is positively correlated with the lightning current,and the lightning current has a good exponential function with the lightning channel temperature,and the relationship between the lightning current and the lightning channel temperature in nature has a good consistency.(3)In order to solve the problems of high breakdown voltage and power frequency following current existing in the gas gap discharge of the lightning protection,based on the theoretical analysis of Townsend theory and Parson's law,we construct a model of the multi-gap for gas discharge.Through analyzing the theory of gas discharge and the result of experiment,we can draw some conclusions as follows:Compared to the traditional gas discharge tube,the breakdown voltage of our model can be decreased for 5 times and the response time can be shorten to 200ns.Furthermore,the rising rate of residual voltage can be reduced to the maximum extent of 0.3kV·?s-1.Besides,the model of multi-gap gas discharge can even reduce or remove the power frequency follow current within a certain range of lightning current,which has a certain value in the practical application.(4)In terms of that the problem of fuse breaking in 8/20?s waveform of lightning current,when the lighting current flows through the fuse,the instant temperature of its melt stream rises;and the analysis of current-carrying conductor influenced by ponderomotive force mechanism when lighting current flows through a conductor;and selecting a lead aluminum alloy fuse,using 8/20?s waveform of lightning current to perform impulse test to consist with the theory of the let-through energy I2t of the fuse when the power frequency melting current of the fuse is below 3A;and to consist with the theory that the applied force vector sum of the transverse electric field and all directional drift electrons are ponderomotive force when the power frequency melting current of the fuse is above 5A,which has something referential value.(5)In the signal system,the value of the decoupling resistance of the signal surge protector(SPD)and the size of the distributed capacitance are tested.The influence of the distributed capacitance of the decoupling resistor and the transient suppression diode(TVS)on the signal transmission is analyzed.Pressure and flow pass with the decoupling element resistance changes and with the clamping device DC voltage changes in the law.And the feasibility of using 1/4? microwave coaxial cable for lightning protection is verified by experiments.