PROTECTIVE RELAY CAPABLE OF PROTECTION APPLICATIONS WITHOUT PROTECTION SETTINGS

摘要

A protective relay for current differential protection for a selected power line. The relay comprises a local current differential relay for protection of a selected power line portion of a power system, the local current differential relay having the capability of sampling three phase current values from its location on the power line at selected intervals of time and transmitting them to a remote relay also connected to the selected power line for current differential protection. The remote relay is not coordinated with the local current differential relay for protection functions. The local current differential relay includes a sensing function for determining when the relay is connected to a remote relay which has adjustable settings for fault determination, wherein the local current differential relay, upon such determination, disables any protection functions therein while continuing to provide phase current values to the remote relay and to receive trip commands from the remote relay.