Abstract
In this experiment the DC breakdown phenomenon of needle-needle in a quartz tube is studied in air at atmospheric pressure. The breakdown voltage of needle-needle electrodes in a narrow tube is higher than that without tube, unlike that the typical surface flashover with dielectric gets lower breakdown voltage. Besides, the smaller the tube diameter (D) is and the larger the gas gap (d) is, the more the breakdown voltage increases. A special experimental device is used to exactly observe the position of the capillary discharge channel in the microspace with two vertical views. The photographs show that on the condition of narrower tube and larger gas gap, the surface discharge propagates along the dielectric surface and it proceeds to a spark following the tube axis at a higher applied voltage for accumulated charge and the leakage current through tube wall. The characteristic of capillary discharge is mainly influenced by the value of D and d. The experiment result indicates the critical size of D and d is approximately 2.5 mm as the same order of 2 mm that is the transverse estimated size of the electron avalanche of the streamer in air at atmospheric pressure.
Sign-in/Register to access full text options 
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 callMore From: IEEE Transactions on Dielectrics and Electrical Insulation
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.
