SELF-GENERATED OVERVOLTAGES DUE TO OPEN-PHASING OF UNGROUNDED-WYE DELTA-TRANSFORMER BANKS

Authors
WALLING RA HARTANA RK ROS WJ DECESARO FP MARZ MB PLUMMER CW
Citation
Ra. Walling et al., SELF-GENERATED OVERVOLTAGES DUE TO OPEN-PHASING OF UNGROUNDED-WYE DELTA-TRANSFORMER BANKS, IEEE transactions on power delivery, 10(1), 1995, pp. 526-533
Citations number
12
Categorie Soggetti
Engineering, Eletrical & Electronic
Journal title
IEEE transactions on power delivery → ACNP
ISSN journal
08858977
Volume
10
Issue
1
Year of publication
1995
Pages
526 - 533
Database
ISI
SICI code
0885-8977(1995)10:1<526:SODTOO>2.0.ZU;2-W
Abstract
Disconnecting one phase of an ungrounded-wye delta transformer bank fr om the source can result in severe overvoltages due to natural shift a nd ferroresonance. Neutral shift overvoltages and quantified and their impact on metal-oxide surge arresters are evaluated. Ferroresonance i s shown by test data to occur when low-loss banks, 15 kV and higher, a re open phased. Design and operating practices to eliminate or mitigat e these self-generated overvoltages are discussed.