Modelling and analysis of a power line communication system with QPSK modem for renewable smart grids

Monitoring and metering processes are required to be performed in renewable energy conversion systems like smart grid applications of the conventional grid system. These processes concerning renewable energy sources are analyzed in this paper in order to propose a solution for solar power systems. The DC-AC conversion system proposed in this paper covers a solar power plant with a maximum power point tracking system and IGBT based three-phase inverter to generate three-phase AC line voltages. The modelled transmission line is not only used to carry the generated voltage but also to transmit the generated power rate of the solar plant in real-time. The power line communication (PLC) infrastructure employed is based on Quadrature Phase Shift Keying (QPSK) modems. In order to overlap QPSK modulated data to the three-phase transmission line at the inverter and grid sides a coupling interface is also designed in the study. The current, voltage and power data generated by the photovoltaic (PV) panels are successfully monitored over transmission lines owing to the developed system. As a result, additional monitoring costs are eliminated by using the proposed technique instead of SCADA or Ethernet-based systems.