Placing and setting of out-of-step relays

This paper shows that shunt elements (loads, shunt reactors, et cetera) should be considered when constructing the impedance locus that the swing traces in the complex plane. A method for constructing the impedance locus at any location in a power system with or without shunt elements is presented. Rules for identifying the busbar that is best suited for placing out-of-step (OOS) relays are presented.