Simulation of propagation characteristic of ultra high frequency signals in power transformers using finite difference time domain method

In order to study the propagation characteristics of Ultra High Frequency (UHF) signals excited by partial discharge in an actual power transformer, a simulation model of the power transformer is established using Finite Difference Time Domain (FDTD) method to simulate the propagation progress of the UHF signals. The receiving signals in different points and planes are analyzed by time domain and frequency domain methods. The results show that due to the complicated structure, the magnitude of the receiving signals vary greatly with places and the distribution of energy also varies very much. The higher the frequency, the greater the attenuation.