Simulation of LXPE Cable Insulation On-line Monitoring Based on TM Electromagnetic Wave Spectrum Characteristics
In this paper, an on-line monitoring method of coaxial cable based on TM mode electromagnetic spectrum method is presented. The TM electromagnetic wave above the cut-off frequency is injected between the outer semiconductor layer and the main insulating layer of XLPE cable, and the dielectric coefficient of the main insulating layer is on-line monitored by utilizing the spectrum characteristics of the interaction between the electromagnetic wave and the main insulating layer. Using FDTD method, the spatial distribution of electric field and reflection waveforms of XLPE cable cross section are simulated by using Gaussian pulse waveform and sinusoidal waveform as the excitation sources respectively. The simulation results show that under the condition of two kinds of excitation sources, there are special spectrum characteristics which can be used as the basis of on-line monitoring.