Abstract
MicroGrids comprise low voltage distribution systems with distributed energy sources, storage devices and controllable loads, operated interconnected with the main power grid or autonomously, in a controlled coordinated way. Storage devices are absolutely essential for MicroGrid autonomous operation. However, depending on the operating conditions, their limited storage capacity is a major drawback and might compromise successful MicroGrid islanded operation. In this paper is proposed an index to evaluate MicroGrids security regarding an unplanned transition to islanded operation due to disturbances in the upstream Medium Voltage network. An Artificial Neural Network tool is proposed to forecast the security index for a credible range of operating scenarios. The usage of Artificial Neural Networks is emphasized due to its computational speed for on-line performance and its flexibility for providing corrective actions for insecure operating conditions in order to achieve a seamless transition from interconnected to islanded operation. © 2007 IEEE.

Abstract
From the studies developed so far, it is a general consensus that Electric Vehicles (EV), when properly managed, can provide many benefits to the grid operation. In the power systems of islands the potential benefits may be even larger. The case of S. Miguel Island, in the Azorean archipelago, may be one of such cases. This island achieves typically an annual peak power of 75 MW and a valley slightly higher than 30 MW. Currently, around 75% of its installed capacity is formed by fuel units, 22% by geothermal units and the rest by small hydro units. Yet, there are numerous unexplored endogenous resources in this place, especially geothermal and wind power, which cannot be used due to technical restrictions. Geothermal is limited by the valley load as the involved technology is not suited for load following, even with very small ramp rates. Wind power requires sufficient conventional spinning reserve to be safely integrated due to the variability of the wind resource. High EV integration, with an adequate charging management, would then increase base load allowing further geothermal and a reduced need for conventional spinning reserves. This paper evaluates the benefits of the presence of EV as controllable loads performing frequency control in a scenario with abundant wind resource availability, where a sudden loss of wind power production over a short period of time occurs. Ultimately, this work will show that S. Miguel power system would benefit from the presence of EV. A comparison with the conventional approach considering EV as regular loads will also be performed for benchmarking purposes.

Abstract
The massive interconnection of offshore Wind Farms (WF) brings challenges for the operation of electric grids. The predicted amount of offshore wind power will lead to a smaller ratio of conventional units operating in the system. Thus, the power system will have less capability to provide fast dynamic regulation. Despite of offshore WF being able to inject power on the AC grid through High Voltage Direct Current (HVDC) convertors, they cannot participate on frequency support by the intrinsic decoupling that DC adoption brings. This paper proposes a control methodology, based on local controllers, to enable the participation of offshore WF in primary frequency control. Additionally, enhancements were made on the Wind Energy Converters (WEC) controller to make them capable of emulating inertial behaviour. Tests were performed in a multi-terminal DC network with two off shore wind farms to assess the feasibility and effectiveness of the concept in a communication-free framework.

Abstract
This paper provides a general overview of the initial developments in the REIVE project (Smart Grids with Electric Vehicles). The main focus of the project is on smart grid infrastructures for large scale integration of EV and micro-generation units. It is a natural evolution of the InovGrid project promoted by the EDP Distribuição - the Portuguese Distribution Network Operator - and allows the development of seminal concepts and enabling technological developments within the Smart Grid paradigm. This paper presents the management and control architecture developed to allow electric vehicle integration in smart grid operation. Additionally, it presents the major impacts in distribution grids of the simultaneous deployment of electric vehicles, micro-generation and smart grid technologies.

Abstract
This paper describes the main results of the MERGE project relative to Electric Vehicle (EV) charging strategies and the impacts of EV integration on the steady-state grid operation. MERGE is a €4.5m, collaborative research project supported by the European Commission's Seventh Framework Programme (FP7). The consortium includes utilities, regulators, commercial organisations and universities with interests in the power generation, automotive, electronic commerce and hybrid and electric vehicle sectors across the entire European Union (EU). One of the MERGE project missions is to evaluate the impacts that EV will have on EU electric power systems, exploring EV and SmartGrid/MicroGrid simultaneous deployment, together with renewable energy increase, to achieve CO 2 emission reduction through the identification of enabling technologies and advanced control approaches. The work presented proposes three charging strategies, dumb charging, multiple price tariffs and smart charging, and uses EV integration scenarios of adherence to these charging schemes. The resulting scenarios are tested using an algorithm coded with Python and using PSS/E, created within the MERGE framework to study EU grids steady-state behaviour. Additionally, the critical mass of EV adherence to smart charging schemes that brings positive impacts to the distribution grids operation was also evaluated.

Abstract
Under normal operating conditions, a MicroGrid (MG) is interconnected with the Medium Voltage (MV) network. However, planned or unplanned events like maintenance or faults in the MV network, respectively, may lead to MG islanding. In order to deal with islanded operation and even black start following a general blackout, an emergency operation mode must be envisaged. Two possible control strategies were investigated and are described in this paper in order to operate a MG under emergency mode. A sequence of actions for a well succeeded black start procedure, involving microgeneration units, has also been identified contributing for an increase in distribution network reliability.