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This paper describes the integration process between two tools in order to perform co-simulation for representation and analysis of dynamic environments in the context of smart grids. The integrated tools are Mosaik, a software to co-simulation management, and PADE, a software to multi-agent systems development. As a study case for demonstrate the integration, a scenary was utilized composed of a low voltage electricity distribution grid with 37 load bus, 20 photo-voltaic distributed generations, randomly connected to load bus, as well as, 20 PADE agents associated to distributed generation, modeling the behavior of electricity storage systems. The simulation results show the integration happening and demonstrate how useful is to model the dynamics of distributed electric resources with multi-agent systems.

Wind power has contributed significantly to the increase in electricity generation, but a decision-making tool capable of dealing with its variability and limited predictability is necessary. For this purpose, a novel self-adaptive approach for kernel recursive least-squares machines named multiple challengers is introduced in this work, which is successfully used to produce very short-term wind power forecasts at eight wind farms in Australia. The proposed method is based on a competitive tracking method, and the algorithm deals with some common difficulties of kernel methods, e.g., the increasing kernel matrix size associated with time and memory complexities and the overfitting problem. The proposed method always considers the new information received by the model, thus identifying changes in the time series, avoiding abrupt loss of information and maintaining a controlled number of examples since there is an adaptive selection of the active kernel. It works with the smallest dictionary possible, reducing the probability of overfitting. Five minute-ahead wind power forecasts are produced and evaluated in terms of point forecast skill scores and calibration. The results of the proposed method are compared with those provided by other kernel-based versions of the recursive least-squares algorithm, an online version of the extreme learning machine method, and the persistence time series model. An increase in the number of kernels used in the ensemble system can lead to better results when compared with those of single-kernel models.

Operational research has made meaningful contributions to practical forecasting in organizations. An area of substantial activity has been in nonlinear modeling. Based on Particle Swarm Optimization, we discuss a nonlinear method where a self-adaptive approach, named as Particle Swarm Optimization with aging and weakening factors, was applied to training a Focused Time Delay Neural Network. Three freely available benchmark datasets were used to demonstrate the features of the proposed approach compared to the Backpropagation algorithm, Differential Evolution and the Particle Swarm Optimization method when applied for training the artificial neural network. Even acknowledging that the effort in comparing methods across multiple empirical datasets is certainly substantial, the proposed algorithm was used to produce 30 min, 1, 3 and 6 h ahead predictions of wind speed at one site in Brazil. The use of the proposed algorithm goes further than only training the artificial neural network, but also searching the best number of hidden neurons and number of lags. The results have shown that the modified Particle Swarm Optimization algorithm obtained better results in all predictions horizons, and the use of it has remarkably reduced the training time.

The advance on smart grid calls for the development and application of distributed intelligent control strategies based on open platforms that provides interoperability. The distributed control must be able to ensure reliable and secure operation of the power systems and enhance supply quality to consumers. The development of a multi-agent system for automatic restoration system (MARS) applied to a real power distribution network is presented. The agents of the MARS are embedded in external hardware to the intelligent electronic devices (IEDs) and communicate with each other via standard Foundation for Intelligent Physical Agents open protocols. To evaluate the MARS performance, a computer simulator was developed in Java to represent the distribution system. Experimental tests were performed in laboratory with the simulator integrated to the MARS via TCP/IP. The tests results have shown that the MARS was able to locate and isolate branches under permanent fault condition and restore healthy branches efficiently through a given switching sequence taking into account the system operational constraints. The proposed MARS has proved the effectiveness of distributed control scheme based on multi-agent system that runs independently of the current technologies of the IEDs of control and protection.

Customer satisfaction counts very much to the electric power distribution companies. The improvement of reliability indices is an effective way to achieve this goal. The optimal placement of power switches is a desirable procedure because while it reduces investment in network assets, it also reduces the number of customers not supplied by outages and, accordingly, improves system reliability. This paper proposes a multiobjective optimization approach for switch placement based on the particle swarm optimization method applied to radial distribution networks of power utilities. The proposed algorithm gives a set of solutions instead of a single one. It intends to be a valuable and flexible tool for planning modern and reliable power distribution networks. Simulation results when using the IEEE 123-node test system and the Roy Billinton Test System are presented as testbeds.

This paper focuses on the steady-state analysis of location and control of distributed power generators encompassing a virtual power plant (VPP). The significant increase worldwide in distributed generation from renewable energy has been largely due to the concern with the environment, the grid access and the strong support policies for the promotion of renewable electricity. Deployment of distributed power plants has contributed to the new concept of VPP as a solution to handle the mix of conventional and distributed energy sources. Produced energy from even small scale generators will be utilized in energy markets and can contribute to the enhancement of the electrical power system. When aggregated, the group of DG would gain access and visibility across the energy markets and the system operation will benefit from optimal use of all available capacity and increased efficiency of operation.

As the wind power technologies evolve from one to another breakthrough and the wind power plants continue its ever increasing penetration in the power system it is a matter of time when the wind power production will be comparable to or even larger than the conventional power generation. In this paper the growth and advances of the wind power industry are described. Relevant aspects related to large-scale integration of wind power into the power system are discussed as the challenges arising from market liberalization, electricity networks innovation, the limited predictability of wind and the voltage and frequency control capabilities.

The Offshore Wind Energy is a technology already widely developed in the European Union with approximately 5GW installed by the end of 2012. In Brazil there are few studies in this segment and potential analysis is essential to indicate the possible locations where parks at sea. The analysis using periods of El Niño and La Niña periods showed that even in the presence of extreme events Ceará coast shows values of mean wind speed will favor the installation of offshore wind farms. A Energia Eólica Offshore já é uma tecnologia amplamente desenvolvida na União Europeia com aproximadamente 5GW instalados até o final de 2012. No Brasil, são poucos os estudos neste segmento e a análise do potencial é essencial para indicar os possíveis locais de implantação de parques no mar. A análise feita, utilizando períodos de El Niño e La Niña, mostrou que mesmo em períodos com presença de eventos extremos, a costa cearense apresenta valores de velocidade média do vento favoráveis á instalação de parques eólicos offshore.

With the latest technological advances in the area of monitoring, protection and control systems, together with the availability of digital communication technologies, the power utilities have been requested to deliver a greater amount of specific information to a broad range of users such as customers, grid operators, regulation agencies and market operators. The power systems make use of permanently installed, integrated, measuring devices that collect, measure, and evaluate one or more characteristic parameters with the intention of automatically determining and reporting the status of the monitored system (Mackrell et al, 2010). Information provided by the real-time monitoring system enables the right decisions to be made for improving security, reliability and performance of the networks. Relay devices form a major part of all monitoring, protection and control systems. These protection relays are multifunctional devices, primarily employed to provide related equipment and system protection, and more recently, they have been adapted to assist the power quality evaluation of power systems. Power quality defines an acceptable set of limits that allow power systems and ultimately the equipment-user to operate within their intended manner with efficiency and expected life span. Power quality deviation refers to a wide variety of electromagnetic phenomena that characterizes the voltage and current at a given time and at a given location on the power system (IEEE Std. 1159, 1995). An electromagnetic phenomenon is a disturbance that may cause variation on voltage and current rms, frequency and waveform that degrade the performance of a device, equipment, process or system. Sometimes power quality can be affected by transient phenomena such as system fault occurrence such as voltage interruption, voltage sag and voltage swell. The protective relays are designed to operate reliably when there are faults in the power system. The relay device must trip on detection of any fault condition and must not trip during normal operating conditions. When the fault is cleared by a relay device, quite often the supply voltage will be restored automatically to its normal operating level. The relay can therefore contribute to restoring the voltage quality of the power system. Protection relaying is primary concerned with clearing faults while power quality is concerned with the delivery of reliable power to defined quality standards (Cease and Kunsman, 2003).

The need for each time more qualified professionals, as well as the cost associated with the release of staff to attend these courses, forced the search for new forms of training that would enable nice professional results and rationalization of human resources provision . To attend this demand, we developed a Virtual Laboratory for Technology Classroom Training and Distance Classes on Eletric Systems Protection. The Virtual Laboratory, called Simulator System for Classroom Training and Distance Classes on Eletric Systems Protection (STOP), can be applied in both classroom and distance training, and is integrated to the Moodle, enriching the environment with a tool capable of simulating real situations can provide a more effective teaching-learning process. A necessidade por profissionais cada vez mais qualificados, bem como o custo associado à liberação de funcionários para participar destes cursos, forçaram a pesquisa de novas formas de treinamento que possibilitassem um bom resultado profissional e racionalizassem a disposição de recursos humanos. Para atender essa demanda, foi desenvolvido um Laboratório Virtual para Capacitação Tecnológica presencial e à Distância em Proteção de Sistemas Elétricos. O laboratório virtual, denominado Sistema Simulador para Treinamento Presencial e a Distância da Proteção de Sistemas Elétricos (STOP), pode ser aplicado em treinamento presencial e à distância e está integrado ao Moodle, enriquecendo o ambiente com uma ferramenta capaz de simular situações reais que pode proporcionar um ensino-aprendizado mais eficaz.

Este trabalho apresenta um método de desenvolvimento de Sistema de Diagnóstico de Faltas (SDF) utilizando Redes de Petri Coloridas Hierárquicas. O SDF proposto visa analisar as informações advindas do SCADA e apresentar diagnóstico de falta sucinto e preciso aos operadores de sistema elétrico, tornando a tarefa de diagnóstico de falta, mais rápida, confiável e menos estressante. O método proposto é desenvolvido e aplicado a uma subestação típica de distribuição, digitalizada, de 15 MVA, 69/13,8 kV, pertencente ao sistema de distribuição da Companhia Energética do Ceará - COELCE. This paper presents a methodology for the development of a Fault Diagnosis System (FDS) based on Hierarchical Colored Petri Nets. The proposed FDS aims to evaluate the information from the SCADA and to present a fault diagnosis sucint and accurate to the power system operators, causing the task of fault diagnosis faster, reliable and less stressful. The proposed methodology is developed and applied to a typical distribution substation with digital relays, 15 MVA, 69 kV/13,8 kV, owned by the local distribution utility, Companhia Energética do Ceará (Brazil).