Abstract
This paper presents a methodology to make EV able to contribute to secondary frequency regulation, by participating in Automatic Generation Control (AGC). The aggregator entity is used in this methodology to act as intermediate between the AGC and the EV controllers. The case-study used is an approximation of the Portuguese transmission/generation network, including existing tie lines with Spain, to which a solid three-phase short circuit was applied. After the disturbance, the impact of EV in the AGC operation was studied for two different situations: EV contributing to secondary frequency regulation and EV behaving as uncontrollable loads. The results obtained for both situations were then compared, in terms of interconnection active power flows in the existing tie-lines and its re-establishment time. ©2010 IEEE.

Abstract
This paper investigates dynamic stability and control design of modern electric energy systems as many MW-scale distributed generators (DG) of various types are deployed in the distribution side of electric systems. The paper is mainly concerned about small-signal frequency stability of distribution systems with decentralized or centralized control systems. The Gerschgorin Circle Theory and Hicks Stability Theory are used for verifying sufficient conditions for small-signal stability. The paper also discusses about designing advanced enhancing robustness methods to ensure both safety and stability of modern distribution systems. Finally, the paper closes with a discussion of policies needed to support large penetration of DG units in distribution systems to ensure safety and robustness of the system. ©2010 IEEE.

Abstract
This paper describes technical solutions to be adopted by Electric Vehicles (EV) battery grid interfaces, in order to get the provision of ancillary services to the grid. The developed solution exploits an EV battery charge control approach based in a grid cooperative response to frequency and/or voltage deviations. To be effective, those cooperative actions must result from both centralized/coordinated commands and local/individual EV charger response to the grid behaviour. In a scenario characterized by a massive deployment of EV, the adoption of such a solution allows an improvement on the power system dynamic behaviour, namely in small island grids. ©2010 IEEE.

Abstract
This paper describes a statistical approach developed for assessing the impacts resulting from EV presence in a given electricity network was developed. The algorithm, developed for this purpose, is based on a Monte Carlo method and can be seen as a planning tool that allows obtaining average values for several system indexes, like buses voltages, branches loading and energy losses. Additionally, it also allows identifying the most critical operation scenarios and the network components that are subjected to more demanding conditions and that might need to be upgraded. The example of a small grid from one of the Azores islands, Flores Island, was used for illustration purposes and two scenarios of EV integration were considered: 25% and 50% of the current light vehicles fleet replaced by EV. ©2010 IEEE.

Abstract
In this study, the authors analyse the social welfare impact of the integration of Portugal and Spain in the Iberian electricity market (MIBEL), taking into account the CO(2) price for emissions trading. They model the impact of emissions trading on the daily clearing prices and generation scheduling, and its effects on the benefits of integration as a whole. They compare the impact of market integration in Portugal and Spain and show that the welfare impact of the MIBEL is dependent on the CO(2) prices. From their analysis, they conclude high CO2 prices lead to a change in the merit order. Moreover, natural gas is the generation technology that most benefits from transmission constraints and from high CO(2) prices, as in the base case it is mainly used as a peak technology. The authors have also found that increases in the CO(2) prices do not lead to higher profits. Overall, the introduction of the MIBEL will increase social welfare by reducing generation costs and prices.

Abstract
In the scope of a recently launched European Research Project, a team of experts from public laboratories and TSO is in charge of defining the concepts and methodological approaches to design and analyse the technical and economic feasibility of future HVDC grids. This work aims at identifying, assessing and comparing several possible HVDC network topologies, with appropriate control and protection schemes, able to collect wind energy on large areas, transmit it at the best points to the AC grid and provide the necessary ancillary services for optimising the DC / AC interconnection in normal and disturbed conditions. The methodology adopted for the study and presented in this paper will focus on three main items: 1. identify and assess the economic drivers for the development of off-shore HVDC networks 2. identify the requirements for an optimal operation of the AC / DC interconnected power systems under normal and emergency conditions 3. conceptualise the coordinated control / command and protection plans for HVDC networks This paper gives a comprehensive view of the issues and tasks to be addressed during the run of the project.