MV to LV transformer PLC bypass coupling networks for a low cost Smart Grid rollout

For Smart Grid communication applications, it is desirable to control thousands of customer modems from one location. Modern OFDM Power Line Communications (PLC) modems use signals in the 9 to 95 kHz CENELEC-A frequency band and can be connected directly to LV power lines. These modems can talk across MV⇔LV distribution transformers, but with a very high signal loss. This paper discusses several PLC coupling networks, including a transformer bypass coupling network which results in less than 15 dB loss in signal across MV⇔LV distribution transformers. Such bypass couplers allow one HV⇔MV⇔LV PLC network to cover millions of customers at low cost. Computer simulations for a typical MV⇔LV network with and without PLC bypass couplers are presented.