SKYDDSRELEANORDING FOR KRAFTOVERFORINGSLEDNING

摘要

A phase comparison relaying network wherein a transmitter keying threshold is set at a predetermined value of the current wave at the transmitter end which is offset from the effective zero axis of the current wave. This yields a signal which, when phase compared with the current wave at the receiver end of the protected line section, permits a tripping response in the presence of "outfeed" current at the "weak feed" end of the protected line section which might occur during an internal fault.