Application of UHF sensor on partial discharge in cable and propagation characteristics simulation

On-line partial discharge(PD)detection on high voltage cable is the most important method to find out hidden failures to predict the operational life and to ensure safe and reliable of power grid.The methods and principles of UHF sensor is introduced,electromagnetic coupling sensor and capacitive sensor are analyzed respectively.According to the propagation theory of the electromagnetic wave in coaxial waveguide,using the software HFSS to simulate the electromagnetic field analysis of 110kV cable joint.The simulation results indicates that the propagation of electromagnetic wave of PD in cable joint is related to the frequency,the higher the frequency is,the faster the attenuation is.