Analyse et modélisation du réseau électrique basse tension aux fréquences courants porteurs de la gamme [1 MHz-30 MHz]

Download or read book Analyse et modélisation du réseau électrique basse tension aux fréquences courants porteurs de la gamme [1 MHz-30 MHz] written by Fawsi Issa and published by . This book was released on 2002 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: A power line communication (PLC) signal is a radiofrequency signal which is superimposed to the 50 Hz power wave. These high frequency signals are assumed to propagate in low voltage (LV) networks and to have a spectrum extends from 1 MHz up to 30 MHz. Hence, some numerical data can be transmitted to the customers of the LV power network with high data rates. The proposed services can be internet, voice over IP or even numerical movies. We study the radiated emission likewise the conducted aspects associated with PLC signals. The characterization of the electromagnetic radiations associated with most of both overhead and underground LV transmission media have been done. The numerical proposed models are based on the antenna theory and the finite element method. An original method has been developed using Hertz potentials computation for the modelling of overhead lines. Moreover, some theoretical results with practical applications have been found dealing with the overestimation of the electric field using the freespace impedance. Some aspects relative to the standardization of PLC systems and networks are discussed. The study of the PLC signals propagation in LV networks is proposed at several levels. In the light of the modelling of the lines and cables of the LV network, the modal analysis theory has been applied thus carrying out some propagation eigenmodes optimal in a data transmission way. Some results concerning all the transmission media used on the LV network allowed three patents for an optimal coupling of the PLC signal. The theoretical results coming from the classical transmission line theory have been applied for a complete computation code with an associated graphical user interface for the simulation of single phase networks. Besides, some results of the multiconductor transmission lines theory have been used for the introduction of the modal scattering matrix concept for the computation of voltages and currents knowing the boundary conditions of the studied medium. The complex issue of the modelling of the three phase networks is also analysed. Hence, an original formalism based on scattering matrix has been developed and proposed some simple incoming-outgoing waves formulations of the different elements of a power network.