The Power Quality of the distribution networks and its impact on the Telecommunication Next Generation Access Network

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Application of back-to-back converters in closed-loop and meshed MV distribution grid

This paper deals with the proposal of a connection to form closed-loop or meshes inside one or more medium voltage primary distribution networks. The main idea consists in realizing this connection through a suitable tie converter constituted by two AC/DC converters in back-to-back configuration. In this way, it is possible to control the power flows between two lines or two different grids keeping the radial structure of the system. This can be useful in presence of distributed generation to share the power among many loads connected to different distribution lines. In the paper the proposed system is analyzed, simulated and discussed both in steady state condition and during faults coming from the MV primary distribution network

Protection devices against DC fault in a back-to-back converter applied to distribution grids

This paper considers the possibility to connect two medium voltage primary distribution grids through a DC connection realized by two AD/DC converters in back-to-back configuration. In particular, after a description of the whole system, the effects of a bolted or non-bolted DC fault are analyzed. Then, an active current limiter is proposed to limit the fault currents and keep the controllability of the system. Such a system is then modeled and studied through many simulations that confirm the effectiveness of the proposed current limiter

Indagini sulla qualità dell’alimentazione elettrica lato domanda: il settore dei cementifici

L’industria cementiera in Italia ha visto durante gli ultimi anni una significativa crescita legata all’importante sviluppo del settore immobiliare. In Italia sono presenti più di 90 cementifici appartenenti a 25 diverse aziende, e nel solo anno 2004 la produzione è aumentata del 6%. Da un punto di vista elettro-energetico, i cementifici costituiscono utenze elettriche importanti, tipicamente alimentate in alta tensione. Inoltre analisi approfondite condotte su impianti attivi hanno evidenziato una non trascurabile suscettibilità del processo produttivo ai disturbi della qualità dell’alimentazione elettrica (PQ). L’articolo riporta alcuni principali risultati di un’ampia campagna d’indagine condotta sul settore industriale dei cementifici italiani col principale obiettivo di determinare la suscettibilità del processo produttivo ai disturbi di PQ cercando di individuarne l’origine, i principali effetti, i costi, le possibili soluzioni