Abstract
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

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

Abstract
The scope of this work is to find the best approach to control advanced inverters used to connect electric vehicles to the grid. Phase-locked Loop (PLL) is a grid voltage phase detection that makes use of an orthogonal voltage to lock the grid phase. This method is suitable for both single and three phase systems, although in single-phase, because they have less information, more advanced systems are required. The easiest way to obtain the orthogonal voltage system is using a transport delay block to introduce a phase shift of 90 degrees with respect to the fundamental frequency of the grid voltage. This method is known as Synchronous Reference Frame PLL (SRF-PLL). The use of inverse Park transformation is also possible. To lower the complexity and increasing the filtering of the output signals, methods using adaptive filters are a good alternative. For this approach, the use of a second order generalized integrator (SOGI) or Adaptive Notch filter combined with PLL, Enhanced PLL (EPLL) and Quadrature PLL (QPLL), leads to satisfactory results. © 2011 INESC Coimbra.