The Italian system for Power Quality (PQ) monitoring of MV distribution networks described in the previous paper 0042 of the 19th International Conference on Electricity Distribution [1] has been working for almost 3 years on 600 instruments distributed all over the Italian territory. The paper illustrates the results of monitoring over the last three years and shows how the monitoring of events, (especially voltage dips) is going to consolidate the characterization of the Italian MV network from the PQ point of view.

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Evaluating the possible impact on electric distribution networks of a large number of plug-in electric vehicles (PEV) is becoming of great interest. In fact, during battery charging, PEVs are a widely spread load of significant magnitude and somewhat unpredictable. On the contrary PEV batteries may constitute a significant reserve and may be used to provide storage capability for cheap energy produced by renewable sources and to supply auxiliary services to the grid.The paper presents the preliminary results of an on-going project aimed at evaluating the impact of plug-in electric vehicles on distribution networks with specific regards to low voltage systems. Hypotheses such as battery size, number of users, load profiles without and with different PEV penetration are presented for successive scenarios set-up and simulations.Results are presented and commented. Index Terms--Plug-in Electric Vehicles (PEV), Plug-in Hybrid Electric Vehicles (PHEV), electric distribution networks, electric load profiles.Michele De Nigris and Iva Gianinoni are with ERSE SpA (formerly CESI RICERCA), via R. Rubattino 54,

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The progressive liberalization of the market of electric power gives the user new opportunities in terms of selection of electrical and integrated services providers and motivates electric companies to increase the quality of services offered limiting their costs. In the medium voltage distribution networks, one of the most effective technical drivers to reach a higher level of power quality is the optimization of the cable network operation; this can be achieved through the application of diagnostic tools able of monitoring the conditions of cables and giving necessary indication to extend the expected life of lines, optimize maintenance operations and schedule, thus increasing their productivity. In the specific situation of Italy, where the presence of historic sites, medieval towns and incomparable landscapes are major restraints for the system operator, any preventive maintenance must be well documented and the selection of suitable cable diagnostic systems must be based on the firm belief that the line condition measured is credible, that the diagnostic process has not damaged or aged the tested line and, last but not least, that the system selected can be driven to the site without being blocked into small medieval roads. With this goal in mind, a collaboration between ENEL Distribuzione and CESI has been set up. In particular, a systematic comparison of the most advanced medium voltage cables diagnostic systems available on the market has been carried out, both in laboratory on short cables with simulated defects and in the field on real cables representative of several typical situations: the main results and findings are reported and discussed in this paper. The work reported in the paper addresses only the methods and systems aimed at identifying the presence and the position of specific weak points in cable lines; we do not consider here the integral methods, aimed at checking the overall conditions of the cable insulation, even if the experience in the application of such integral condition assessment techniques has proven to give irreplaceable information. The techniques experimented in the work documented hereafter are considered as complementary to the integral ones and not replacing them. N.4 medium voltage cable diagnostic systems were considered in the program. They were