Abstract
This paper proposes a new methodology for coordinated voltage support in distribution networks with large integration of distributed generation and microgrids. Given the characteristics of the LV networks, it is shown that traditional control strategies using only reactive power control may not be sufficient in order to perform efficient voltage control. Therefore, microgeneration shedding must also be employed, especially in scenarios with extreme microgeneration penetration. An optimisation tool based on a meta-heuristic approach was developed to address the voltage control problem. In addition, neural networks were employed in order to decrease computational time, thus enabling the use of the tool for online operation. The results obtained revealed good performance of this control approach.

Abstract
This paper describes an operational optimization strategy to be adopted at the wind park control level, that enables defining the commitment of wind turbines and their active and reactive power outputs following requests from wind Park Dispatch Centers, assuming that individual wind turbines short-term wind speed forecasts ate known and are expressed as power availability. This operational strategy was also developed with a concern on the minimization of the connection/disconnection changes of the individual wind generators. fora given time horizon. When identifying the active/reactive dispatching policies, wind generators loading capabilities are also taken in account. This optimization tool is especially suited to manage large wind parks.

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In this paper the behaviour of a Portuguese typical Low Voltage (LV) grid and the changes in the Portuguese global generation profile were analyzed, in a daily period, regarding different levels of Electric Vehicles (EVs) integration. The impacts provoked by EVs deployment on the network voltage profiles, branches' congestion levels, grid losses and imbalances between phases were evaluated using a three phase power flow. The first part of this work focused on the determination of the maximum share of electric vehicles, defined as the percentage of conventional vehicles replaced by EVs, which can be integrated into the selected grid, without violating the system's technical restrictions and complying with drivers' requests concerning the foreseen use of vehicles. The maximization of the EVs connected to the grid was performed using two distinct charging strategies: dumb charging and smart charging. The second task was to analyse the impacts of both charging approaches (dumb charging and smart charging) on the prevention of wasting renewable energy surplus. For the purpose of this analysis, a 2011 wet and windy day was considered, where large hydro and wind generation exists. For that specific case, in some periods of the day (mainly valley hours), the hydro and wind generation, added to the must run thermal generation units, will surpass the consumption and renewable energy can be wasted. The results obtained for the LV grid were extended to a National level and the changes in the Portuguese load/generation profiles were computed.

Abstract
This paper presents a comparison of two new advanced statistical short-term wind-power forecasting systems developed by two independent research teams. The input variables used in both systems were the same: forecasted meteorological variable values obtained from a numerical weather prediction model: and electric power-generation registers from the SCADA system of the wind farm. Both systems are described in detail and the forecasting results compared, revealing great similarities, although the proposed structures of the two systems are different. The forecast horizon for both systems is 72 h, allowing the use of the forecasted values in electric market operations, as diary and intra-diary power generation bid offers, and in wind-farm maintenance planning.

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