Speaker
Hulya Kirkici
(Auburn University)
Description
Nano-dielectrics are shown to have improved electrical and dielectric properties compared to the non-filled bulk material. Surface flash-over is one form of breakdown, usually occurs over the surface of insulator between the energized electrodes due to high field stress when the field stress at the insulator/electrode/ambient interfaces. Understanding the characteristics of surface flash over in sub-atmospheric pressures is more important for aerospace systems and vehicles. In space/aerospace power systems, high frequency effects on dielectric breakdown and surface flash-over are due to the switching circuits used in power systems. In this work we present surface flash-over characteristics of two different polymer nano-dielectrics filled with either TiO2 or Al2O3 nano-particles in sub-atmospheric nitrogen. A high frequency unipolar pulsed field varying from 20 kHz to 200 kHz is used in the experiments. The effects of duty cycle and frequency of the applied field, surface condition of the sample, and background pressure on the surface flash-over are presented. A 0.5 cm gap distance is formed by two rounded copper electrodes positioned on top of the sample. The plasma characteristics, such as voltage, current, and optical emission wave-forms are recorded. Dielectric properties such as volume resistivity, polarization current, and dielectric permittivity of TiO2 and Al2O3 filled samples are studied and the differences between these two samples’ surface flashover characteristic are presented.
Primary author
Hulya Kirkici
(Auburn University)
Co-authors
Dr
Muciz Ozcan
(Necmetting Erbakan University)
Mr
Yuxuan Chen
(Auburn University)
