ABSTRACT
The method of symmetrical components provides a practical technology for
understanding and analyzing the operation of a system during power unbal-
anced conditions, such as those caused by faults between phases and ground,
open phases, unbalanced impedances, and so on. In addition, many protective
relays operate from symmetrical component quantities. Thus, a good under-
standing of this subject is of great value and another very important tool in
protection.
