Signal comparison protection system for monitoring transmission paths of the supply network

摘要

The invention relates to a signal comparison protection system for monitoring transmission paths of the supply network, a reference signal being transmitted over additional lines in parallel with the network transmission, and disturbances in the network being identified with the aid of the comparison between network and reference signals. The object of achieving the maximum possible operating reliability at a low cost is achieved in that a frame is formed for the reference signal which is to be transmitted digitally, such that each useful word has a synchronising word of equal magnitude placed before or after it. At the receiving end, the two synchronising words are then checked in a simple manner and transmission errors are confirmed in quasi-real time so that erroneous disconnection of the network is prevented.