Broadband Powerline Communication for Low-Voltage Microgrids

Abstract

The distributed-element transmission line model is modified to account for proximity effects in multiconductor cables and frequency dependent dielectric behaviour providing an accurate prediction of channel attenuation at broadband power line communication frequencies (1–100 MHz). The modified model is verified with scattering parameter measurements and then used as a building block for complex microgrid network modelling. Powerline communication performance tests are conducted using the HomePlug GreenPHY and HomePlug AV. The AV operates successfully up to 600 m on star feeders and on complex radial feeders in the presence of power converter noise. The GreenPHY operates up to 450 m on star feeders and on radial feeders with long branches. However, it cannot connect reliably on radial feeders with short branches due to frequency selective notching. Functionality requires link attenuation less than −60 dB at 30 MHz and the absence of notches that penetrate below −70 dB within the band (1.8–30 MHz). Due to the wide availability and low cost of the AV, it is a sensible choice for reliable broadband digital communications on microgrid networks.