Design and Characterization of a New MV PLC Coupler for Smart Electric Energy Systems

This paper deals with the design, modeling and characterization of a new coupling system for medium voltage (MV) narrow band power line communications (NB-PLC). It exploits the capacitive divider of voltage detecting systems (VDSs) normally used to reveal the mains voltage presence, thus avoiding the use of dedicated MV couplers. The proposed coupling system was patented by the authors. In this paper, the modeling of the VDS capacitive divider is presented, using a proper characterization method. Moreover, the interface card design is described, based on simulation of the whole PLC transmission channel. Laboratory tests are also presented and discussed. More in detail, a frequency response analysis is performed to validate the developed model and the related simulations. Moreover, transmission tests with nPSK modems demonstrate that the proposed coupling system can be effective for narrowband modulated signal transmission. With respect to other tests presented in previous papers, in this paper the experimental characterization and validation was performed in an extended frequency range up to 200 kHz.