Simulation for Electromagnetic Wave Transmission Characteristics in Straight and T-Shaped Tanks of Gas Insulation Switchgear Structures
Yanming Li · Xi'an Jiaotong Daxue xuebao · 2008
Propagation characteristic of electromagnetic which is excited by partial discharge in gas insulation switchgear(GIS) is simulated based on the method of finite difference time domain(FDTD).The transmission characteristics of TEM and TE,and reflected waves generated by T-shaped tanks are analyzed in the straight and T-shaped tanks of GIS structure,via setting the different directions of electromagnetic,comparing the time and frequency domain results of electromagnetic wave in different structures and measurement angles.The results indicate that the amplitude of peak-peak voltage and energy of signals get greater when measuring point is near from the excitation source and the new mode wave probably forms when the signals propagate through the T-shaped tanks because of the effect of wave mode transformation,and TEM can propagate through GIS cavity with little attenuation due to the lack of cutoff frequency in TEM.