Method and structure for coupling power-line carrier current signals using common-mode coupling

摘要

An apparatus and a method for communicating data among transceivers in an electrical utility distribution system where a signal path between the transceivers includes multiple power distribution transformers is described. A first transceiver, common-mode coupled to a secondary of a first power distribution transformer transmits a carrier signal modulated by a data stream to the secondary. The modulated signal is transferred to the primary of the first power distribution transformer which is coupled to the primary of a second power distribution transformer. A second transceiver, common-mode coupled to a secondary of the second power distribution transformer, receives the modulated signal from the secondary. Both transceivers are protected from the high power delivered at the line frequency by filtering capacitors which attenuate signals at the line frequency and pass signals at the carrier signal frequency.