Channel Modeling for Powerline Communications in Series-Connected PV Inverters

The authors have demonstrated an AC-stacked PV-inverter topology allowing each inverter to operate completely autonomously from all the others with the only required communications being a low-bandwidth synchronization signal communicated from the point-of-grid-connection. As in any series-connected PV architecture, communications must proceed through a series of power-electronic devices. This paper proposes an approach for modeling the series-connection as a communications channel. It describes the major noise sources and discusses how these noise sources impact the design of the communications system. It focuses specifically on the design challenges in the AC-stacked architecture, but the generalized model is applicable for any series-connected arrangement.