An Electronic Distance Relay Using a Phase-Discrimination Principle [includes discussion]
F. R. Bergseth · Transactions of the American Institute of Electrical Engineers Part III Power Apparatus and Systems · 1954
An electronic distance relay is described which uses a principle whereby the phase angle of voltage components is compared. A relay time of 1 cycle or less has been realized on tests of a laboratory model. The relay has the feature of simplicity, since only one tube and two diode rectifiers are used per phase.