Prediction of impulse voltage-time characteristics of air and oil insulation for different wavefronts

Author

Sharath, B. ; Usa, S.

Author_Institution

Div. of High Voltage Eng., Anna Univ., Chennai, India

Volume

16

Issue

6

fYear

2009

fDate

12/1/2009 12:00:00 AM

Firstpage

1693

Lastpage

1697

Abstract

The insulation of all the power apparatus in the power system are tested with 1.2/50 Â¿s standard lightning impulse voltage and this waveshape plays an important role in the insulation coordination of the power system. But in practice all the equipment in the power system are exposed to impulses of varying front times from nano seconds to micro seconds. Hence, it is essential to obtain the voltage-time characteristics of impulses of varying front times. But it is impractical to estimate the insulation strength for all possible impulses. To overcome this difficulty a few impulses of different front times from nano seconds to microseconds are generated and their voltage-time characteristics are obtained for air and oil. From these voltage-time characteristics a generalized mathematical model is obtained by regression analysis to predict the impulse voltage-time characteristics of any wavefront and this mathematical model is experimentally validated.

Keywords

air insulation; insulating oils; insulation testing; lightning; power system transients; air insulation; impulse voltage-time characteristic; insulation coordination; lightning impulse voltage; oil insulation; Character generation; Impulse testing; Insulation testing; Lightning; Mathematical model; Oil insulation; Petroleum; Power systems; System testing; Voltage; v-t characteristics, varying wavefront times, VFTO, hyperbolic model, prediction of breakdown time, air and oil insulation;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/TDEI.2009.5361591

Filename

5361591