Laser triggering of electric breakdown in liquids

Author

Sunesson, Anders ; Bårmann, Peter ; Kröll, Stefan ; Walfridsson, Lars

Author_Institution

Dept. of Phys., Lund Univ., Sweden

Volume

1

Issue

4

fYear

1994

fDate

8/1/1994 12:00:00 AM

Firstpage

680

Lastpage

691

Abstract

Electric breakdown in semihomogeneous geometries has been studied in n-hexane and transformer oil using a laser triggering method for fields far below the spontaneous breakdown field. The method uses a laser-produced plasma to initiate the breakdown. Strong self focusing in the liquids was limited by increasing the numerical aperture of the laser beam to >0.20 prior to focusing. Electrical breakdown could be triggered at fields as low as 50 kV/cm in transformer oil and 25 kV/cm for n-hexane. The time lags are between 30 and 200 μs, depending on voltage, liquid, and gap size. Current and light emission measurements of the prebreakdown phenomena are presented and a model for the triggering process is proposed

Keywords

electric breakdown of liquids; electric current measurement; insulating oils; laser beam applications; organic insulating materials; 30 to 200 mus; current measurements; electric breakdown; gap size; laser triggering; laser-produced plasma; light emission measurements; n-hexane; numerical aperture; prebreakdown phenomena; self focusing; semihomogeneous geometries; transformer oil; Dielectric liquids; Electric breakdown; Electrodes; Focusing; Gas lasers; Geometry; Laser theory; Oil insulation; Optical pulse generation; Plasmas;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/94.311711

Filename

311711