Transient model and simulation in three-phase three-limb transformers

Author

Lin, C.E. ; Yeh, J.-C. ; Huang, C.L. ; Cheng, C.L.

Author_Institution

Dept. of Electr. Eng., Cheng Kung Univ., Tainan, Taiwan

Volume

10

Issue

2

fYear

1995

fDate

4/1/1995 12:00:00 AM

Firstpage

896

Lastpage

905

Abstract

When a three-phase three-limb power transformer, whose primary windings are Y-connected with isolated neutral, is energized or reclosed by asynchronous closure of the circuit breaker poles, the transient voltage at the still disconnected transformer terminal and the transient current flowing from the connected windings may reach considerably high values. This can cause serious damage to equipment connected to the transformer. This transient phenomenon is closely related to the switching sequence of the circuit breaker poles, switching-on angles, remanent flux and the magnetic saturation characteristics of the transformer´s iron core. This paper presents a simple and effective method to predict the transient phenomenon of power transformers. The proposed method formulates a model to represent the transient under various operating conditions. Simulations and experiments are both demonstrated to support the proposed method

Keywords

circuit breakers; power system transients; power transformers; transformer cores; transformer windings; Y-connected; asynchronous closure; circuit breaker poles; experiments; iron core; isolated neutral; magnetic saturation characteristics; modelling; primary windings; remanent flux; simulation; switching sequence; switching-on angles; three-limb power transformer; three-phase; transformer terminal; transient current; transient voltage; Circuit breakers; Circuit faults; Circuit simulation; Iron; Magnetic flux; Magnetic switching; Power transformers; Saturation magnetization; Switching circuits; Transformer cores;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.400840

Filename

400840