Performance evaluation of Power Line Communications over power transformers

Power Line Communications (PLC) are used in Automatic Meter Reading (AMR) systems more and more this day. This paper analyses the problems encountered when the PLC signal is needed to be sent through the body of a power transformer, we have made field tests to verify if communication can take place and with what performances. For this a comparative analyze of protocols PRIME and G3-PLC data transfer has been made, when communication took place as follow: through the secondary winding of a MV/LV power transformer from a phase to another, through two power transformers from one secondary LV winding to the other one secondary LV winding over the MV power line that feeds the both of them, and through the second power transformer when distance on one phase was increased to 50 m. Parameters as BER (Bit Error Rate), PER (Packet Error Rate), data rate the signal spectrum are analyzed.