Abstract
This work studies the correlation between secondary electron emission (SEE) characteristics and impulse surface flashover in polyethylene nanodielectrics both theoretically and experimentally, and illustrates the enhancement of flashover voltage in low-density polyethylene (LDPE) through incorporating Al2O3 nanoparticles. SEE characteristics play key roles in surface charging and gas desorption during surface flashover. This work demonstrates that the presence of Al2O3 nanoparticles decreases the SEE coefficient of LDPE and enhances the impact energy at the equilibrium state of surface charging. These changes can be explained by the increase of surface roughness and of surface ionization energy, and the strong interaction between nanoparticles and the polymer dielectric matrix. The surface charge and flashover voltage are calculated according to the secondary electron emission avalanche (SEEA) model, which reveals that the positive surface charges are reduced near the cathode triple point, while the presence of more nanoparticles in high loading samples enhances the gas desorption. Consequently, the surface flashover performance of LDPE/Al2O3 nanodielectrics is improved.
Highlights
Surface flashover of insulating material is of prime importance in the electrical, pulse power, and electronic fields
This work studies the correlation between secondary electron emission (SEE) characteristics and impulse surface flashover in polyethylene nanodielectrics both theoretically and experimentally, and illustrates the enhancement of flashover voltage in low-density polyethylene (LDPE) through incorporating Al2O3 nanoparticles
The surface charge and flashover voltage are calculated according to the secondary electron emission avalanche (SEEA) model, which reveals that the positive surface charges are reduced near the cathode triple point, while the presence of more nanoparticles in high loading samples enhances the gas desorption
Summary
Surface flashover of insulating material is of prime importance in the electrical, pulse power, and electronic fields. In vacuum-reliant equipment, the flashover typically occurs at a much lower voltage than that of vacuum breakdown.[1] Flashover often occurs on the surface of a material, culminating in a either low-resistance arc or a high-current discharge. SEEA indicates an electron cascade along the surfaces of the material It can convincingly explain the impulse, a nanosecond pulsedflashover, as the response to magnetic fields and the role of the SEE coefficient, but it is difficult to use to explain some direct current (dc) flashover characteristics, such as the decays of seconds in dc flashover. This work studies the impulse surface flashover and SEE characteristics of LDPE/Al2O3 nanodielectrics in vacuum. In regard to SEEA charging, this study demonstrates by simulation the role of SEE in surface flashover of nanocomposites. The decrease of surface flashover voltage observed in high loading samples can be ascribed to the increase of gas desorption
Sign-in/Register to view highlights & summary 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 callDisclaimer: 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.
