Theoretical Calculation of Inrush Currents in Three- and Five-Legged Core Transformers

Author

Sáinz, Luis ; Córcoles, Felipe ; Pedra, Joaquín ; Guasch, Luis

Author_Institution

Dept. of Electr. Eng, Univ. Politecnica de Catalunya, Barcelona

Volume

22

Issue

2

fYear

2007

fDate

4/1/2007 12:00:00 AM

Firstpage

986

Lastpage

995

Abstract

In this paper, a theoretical study of the three-phase transformer behavior in the presence of a sag is presented by considering that the fault clearing is produced simultaneously in all phases. Analytical expressions of the magnetic flux and the inrush current after voltage recovery are obtained, and the results presented in the literature are analytically justified. The influence of depth, duration, and the initial point-on-wave on the peak value of the inrush current are studied for all sag types. Simple expressions to obtain the value of the current peaks are presented

Keywords

magnetic flux; power supply quality; power transformers; five-legged core transformer; inrush currents; magnetic flux; three-legged core transformer; voltage recovery; voltage sag; Magnetic analysis; Magnetic cores; Magnetic flux; Magnetic separation; Phase transformers; Power system modeling; Saturation magnetization; Surges; Transformer cores; Voltage fluctuations; Inrush current; transformer model; voltage sag;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/TPWRD.2006.881428

Filename

4141163