A case of abnormal overvoltages in a Petersen grounded 132-kV system caused by broken conductor

Author

Gustavsen, Bjørn ; Walseth, Jan Åge

Author_Institution

SINTEF Energy Res., Trondheim, Norway

Volume

18

Issue

1

fYear

2003

fDate

1/1/2003 12:00:00 AM

Firstpage

195

Lastpage

200

Abstract

This paper analyzes a case where a broken phase conductor in a Petersen grounded system caused extensive damage and outages due to excessive stationary overvoltages. It is shown that the high overvoltages resulted from a combination of the following: (1) the fault occurred on a radial connection, (2) the total compensation was close to 100%, and (3) the compensation of the two subnetworks defined by the fault was far from 100% (one subnetwork was undercompensated and the other overcompensated). Overvoltages calculated by a simple model compare favorably with recorded results. The overvoltages are shown to be strongly dependent on the compensation level, the compensation distribution, the shunt conductance to ground, and the load. A least squares method is used for estimating the shunt conductance based on a measured resonance curve.

Keywords

coils; conductors (electric); earthing; electric admittance; least squares approximations; overvoltage; 132 kV; Norway; Petersen coils; Petersen grounded system; abnormal overvoltages; arc suppression coils; broken phase conductor; compensation distribution; compensation level; fault; high overvoltages; least squares method; radial connection; regional transmission systems; resonance curve; shunt conductance; stationary overvoltages; subnetworks compensation; total compensation; Circuit breakers; Circuit faults; Coils; Computer aided software engineering; Conductors; Fault currents; Least squares methods; Power transformers; Resonance; Surge protection;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/TPWRD.2002.803825

Filename

1159918