Breakdown of polyurethane hard-foam insulation under short-time HV stress

Author

Koenig, D. ; Bayer, B. ; Heller, H.J.

Author_Institution

Tech. Univ. of Darmstadt, West Germany

Volume

24

Issue

2

fYear

1989

fDate

4/1/1989 12:00:00 AM

Firstpage

239

Lastpage

248

Abstract

Breakdown performance of dielectric material with microporous structure is investigated under short-term voltage stress. The material is a self-skinning polyurethane hard foam. Experimental research on impulse voltage strength and partial-discharge behavior in AC run-up tests shows aspects of gas breakdown in the pores. The structure of the material and the form and size of pores are investigated by optical means and SEM. The composition of the gas in the pores and the diffusion processes are analyzed. These results lead to a model of short-time breakdown of the complete microporous dielectric insulating system, taking into account the breakdown of a single pore according to the relevant theory of gas breakdown

Keywords

composite insulating materials; electric breakdown; foams; high-voltage techniques; partial discharges; polymers; porous materials; AC run-up tests; HV stress; gas breakdown; impulse voltage strength; microporous structure; model; partial-discharge behavior; polyurethane hard-foam insulation; self-skinning polyurethane hard foam; short-term voltage stress; short-time breakdown; Breakdown voltage; Dielectric breakdown; Dielectric materials; Dielectrics and electrical insulation; Diffusion processes; Electric breakdown; Gas insulation; Impulse testing; Optical materials; Stress;

fLanguage

English

Journal_Title

Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

0018-9367

Type

jour

DOI

10.1109/14.90282

Filename

90282