FORFARANDE FOR OVERFORING AV BINERA MEDDELANDEN OVER EN VEXELSTROMSKRAFTLEDNING

摘要

A method and an apparatus for communicating over electric power lines in a direction from load to source is disclosed. The power line voltage wave is loaded in a predetermined pattern to produce a corresponding pattern of signaling currents at a receiving site. Detection of the signaling current is accomplished in the preferred embodiment by integrating the current in the phase or the neutral of the feeder that serves the signaling site during predetermined time windows which are synchronized with the power line voltage wave. The current integration is performed in accordance with a detection algorithm to accumulate principally the current differences that are attributable to the signaling currents while in the presence of steady and transient currents on the feeder.