Case study of ANSI standard delta-wye distribution transformer

Author

Al-Hajri, Muhammad Tami

Author_Institution

Power Distribution Dept., Saudi Aramco, Dhahran

fYear

2006

fDate

11-14 June 2006

Firstpage

205

Lastpage

209

Abstract

An over current relay (51N) of a distribution feeder that feeds a branchy overhead line failed to eliminate a fault, which resulted from a fallen conductor at the primary side of the delta-wye distribution transformer. This was linked to the earth´s high resistance. In the first part of this paper, the aforementioned reason will be proven to be not credible and that the load-side fallen conductor resulted in a very small return current that cannot be detected. In the second part of this paper, the fact that the voltage will build up at the distribution transformer primary side in case the transformer has a primary single phase blown fuse and unbalance loads will be presented

Keywords

ANSI standards; earthing; electric fuses; overhead line conductors; power distribution faults; power transformers; relays; ANSI standard; conductor; delta-wye distribution transformer; distribution feeder; earth resistance; fault elimination; fuse; over current relay; overhead line; ANSI standards; Computer aided software engineering; Conductors; Fault currents; Fuses; MATLAB; Mathematical model; Power transformer insulation; Relays; Substations;

fLanguage

English

Publisher

ieee

Conference_Titel

Electrical Insulation, 2006. Conference Record of the 2006 IEEE International Symposium on

Conference_Location

Toronto, Ont.

ISSN

1089-084X

Print_ISBN

1-4244-0333-2

Type

conf

DOI

10.1109/ELINSL.2006.1665293

Filename

1665293