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The Smart Grid vision along with the future deployment of Electric Vehicles presents numerous challenges in terms of grid infrastructure, communication, and control. In this context, Advanced Metering Infrastructure solutions are envisioned to be the active management link between utilities and consumers. This paper presents a survey of potential AMI functionalities particularly developed to foster the large scale deployment of EV in Smart Grids. For this accomplishment, the concepts of Automated Meter Reading, Automatic Meter Management and Smart Metering are revisited. Furthermore, different EV charging approaches are outlined and included in the functionalities under the Vehicle-To-Grid framework. Finally, AMI use cases are described under the Vehicle-to-Home perspective.

This paper presents an adequacy and security evaluation of electric power distribution systems with distributed generation. For this accomplishment, bulk power system adequacy and security evaluation concepts are adapted to distribution system applications. The evaluation is supported by a combined discrete-continuous simulation model which emulates the distribution system operation. This model generates a sequence of operation states which are evaluated from a steady-state perspective using AC power flow computations. Frequency and voltage stability are also assessed using dynamic simulation in order to verify the feasibility of islanded operation. Simulation results are presented for the RBTS-BUS2-F1 as well as an actual feeder from the South of Brazil. The results emphasize the need to consider adequacy and security aspects in the distribution system assessments, mainly due to the ongoing integration of distributed energy resources.

Wind and solar power are well known intermittent power sources with high availability uncertainties. Hence, whenever they are integrated to distribution systems, these power sources can increase significantly the complexity of system operation. This paper presents an impact analysis of distributed energy resources integration on distribution systems, focusing mainly on reliability aspects. Therefore, an interesting algorithm to correctly determine the amount of capacity that may be transferred to other feeders is presented and discussed, taken into consideration the presence of distributed generation. The methodology is tested in a typical Brazilian distribution system, assuming the integration of a diesel-based combined heat and power unit, wind turbines, and solar panels. The results provide general insights regarding the benefits of applying distributed generation to alleviate load transfer restrictions.

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This paper introduces a modified edition of classical Cespedes' load flow method to radial distribution system analysis. In the developed approach, a distribution network is modeled in different complex reference systems and reduced to a set of connected equivalent subnetworks, each without resistance, while graph topology and node voltage solution are preserved. Active power losses are then not dissipated in the modeled subnetworks and active power flows can be obtained as a consequence of radiality. Thus, the proposed method preprocesses a series of variable transformations concomitant to an iterative algorithm using a forward-backward sweep to arrive at the load flow solution. The proposed approach has been tested using literature and actual distribution networks, and efficiency improvements are verified in comparison to Cespedes' load flow method. [1,2] provides the steady-state condition for power systems and is one of the most important numerical tools to system planning and designing. In order to design solutions to power distribution system real-time operation [3], modeling and analysis might take into account unbalanced operation and detailed features of each component connected to the networks. On the other hand, in long-term planning stages, some hypotheses and simplifications can be assumed (e.g. balanced operation, constant power load) due to, for instance, uncertainties regarding future load profiles and distributed generation productions. This is the case in adequacy evaluations [4,5], where hundreds of thousands of load flow analysis may be executed, while performance indices are estimated by modeling failure/repair cycles of components and load/generation profiles as stochastic processes.Detailed distribution system modeling and analysis is a well established topic, covered in books such as [6]. Simplified/single-phase load flow modeling and analysis dates mostly to the 80's and 90's and can be divided into two groups: the first group comprises Newtonian based methods adjusted to distribution system analysis [7,8] and the second group includes methods based on iterative forward-backward sweep processes [9,10,11,12,13,14]. The sweep based techniques are known by their efficiency and take advantage of the fact that distribution networks usually are radially operated.Forward-backward sweep methods employ the following general procedures: (a) assuming a flat start or an approximate solution, current or power downstream each node is estimated in a backward sweep (from end nodes towards the substation node); (b) using estimates from the previous step, node voltages are updated in a forward sweep (from the substation node towards end nodes); (c) these two steps are repeated up to the convergence of node voltages.Among the several variations of sweep techniques, the one proposed by Baran and Wu [11,12] stands out by employing a set of equations, known as Distflow branch equations, that recursively relates active power, reactive power and voltage magnitudes. Cespedes [9] steps ahead by addressin...

This paper presents a decentralized architecture for the islanding operation of distribution grids with large volume of distributed generation. This architecture involves the definition of network blocks which share the responsibility of frequency control. The control block abstraction was particularly designed to support the transition from regular grids to smart grids. In addition, the control schemes were developed using an agentbased paradigm. Hence, an agent-based simulation platform was implemented using libraries from the Java Agent Development Framework (JADE). The control schemes were evaluated using a test system with different sorts of distributed energy resources and modeled in the EUROSTAG environment. Simulation results show the effectiveness of the control architecture when different failure events are applied to the test system.

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