Abstract

Surface flashover properties should meet stringent requirements for the use in electrical equipment under high voltage DC environments. With the aim of enhancing surface flashover properties and understanding the mechanisms involved at ambient conditions, epoxy nanocomposites with different weight proportions of nano-TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> were prepared. A silane coupling agent was selected to functionalize the TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , the effect of which on nanoparticles dispersion and distribution was perused through scanning electron microscopy and infrared spectroscopy. DC surface flashover measurements in five normally used ambient conditions (N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , air, CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> and vacuum) were conducted and results were analyzed relating to loading content, gas parameters, surface trap parameters as well as electrical conductivity of nanocomposites. Outcomes indicate that with low content of nanoparticles, the density of deep traps was increased, showing a positive effect on inhibiting surface flashover. When the nanoparticle content is higher than 1 wt%, the overlapped transitional region reduced the energy level of traps, resulting in a poor display of surface flashover voltages. It was found that the nanoparticle content had a greater influence on surface flashover in vacuum. Electron negativity, ionization coefficient and mean free path of gases were taken into account to explain why surface flashover in SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> appeared to be the highest, whereas in N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , it was the lowest. At last, effects of gas-solid interactions on surface flashover combining surface-trap characteristics, secondary electron-emission contributions and gas molecule impact-ionization characteristics were analyzed.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.