Method for setting the resistive reach of quadrilateral characteristics of distance relays

A new method for setting the resistive reach on quadrilateral characteristics of distance relays is proposed in this article. The method is based on: a) analysis of the impedances seen by the relay (apparent impedances); and b) explicit definition of the protection desirable attributes for each analyzed zone (selectivity, sensitivity). In the proposed method, the resistive reach setting is calculated assuming that the reactive reach setting has been previously defined. The proposed method was applied in an example with 18 distance relays and its solution was compared with a conventional simplified solution. The conventional simplified solution consists in setting the resistive reach by multiplying the reactive reach by a constant factor. The result obtained with the proposed method is different since there is not a constant factor among the settings of the reactive and resistive reaches.