High Frequency MV/LV transformer modelling for Power Line Communication applications

In recent years, design and service evolution in electric distribution networks are mainly guided by the increasing in the customer consumption and the emergence of new sources and loads such as renewable energy, electric and hybrids vehicles. The lack of control over these new constraints in the future may lead to technical and financial problems. Therefore, establishing a supervisory strategy offering a more advanced knowledge of distribution networks is an interesting alternative compared to an expensive strengthening of current networks. Power Line Communication (PLC) technologies present a significant advantage for a supervision application of electric distribution networks. Nevertheless, these networks have not been developed to transmit High Frequency (HF) signals like a PLC. Thus, they induce difficult propagation conditions for PLC. This paper presents an approach to model in HF one element of the distribution network: the MV/LV transformers which established the connection between Medium Voltage (MV) and Low Voltage (LV). The proposed modeling method is based on a black box model whose parameters are obtained from various impedance measurements. It has been applied to four transformers most commonly used by Gérédis, French Distribution System Operator (DSO).