EHV transformer bank unbalance: practical issues and solutions

Author

Gutman, R. ; Wagenaar, L.B.

Author_Institution

American Electr. Power Service Corp., Columbus, OH, USA

Volume

11

Issue

4

fYear

1996

fDate

10/1/1996 12:00:00 AM

Firstpage

1830

Lastpage

1835

Abstract

An unconventional tap configuration has been implemented in AEP´s South Canton 765/345/34.5 kV 3*500 MVA transformer bank to counter the combined effects of impedance mismatch within the bank and the natural unbalance of the EHV transmission system. These effects manifest themselves as unequal phase voltages and loadings and as elevated neutral and tertiary circulating currents in the bank, capable of reaching high magnitudes during heavy loading conditions. This paper describes the South Canton bank unbalance, the concerns it raised, and the actions taken by AEP to control its possible adverse effects on the integrity and operation of the South Canton Station (USA) facilities

Keywords

load (electric); power system analysis computing; power system stability; power transformers; power transmission; transmission networks; 34.5 kV; 345 kV; 500 kVA; 765 kV; EHV transformer bank unbalance; EHV transmission system; USA; computer simulation; heavy loading conditions; impedance mismatch; neutral currents; power system unbalance; stability; tertiary circulating currents; unconventional tap configuration; unequal loading; unequal phase voltages; Counting circuits; Data acquisition; Impedance; Personnel; Phase transformers; Power cables; Power transmission lines; Steady-state; USA Councils; Voltage;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.544264

Filename

544264