Reliability assessment of distribution systems incorporating feeder restoration actions

This paper proposes a computational methodology for the evaluation of the IEEE reliability indices for distribution systems considering distribution system restoration. The goal of the proposed methodology is to move from a reliability assessment based on historical data to a computational approach. The developed tool allows the evaluation of the Service Restoration benefits, in terms of customers interruption duration in case of fault occurrences. Distribution System Restoration (DSR) is aimed at restoring loads after a fault by altering the topological structure of the distribution network while meeting electrical and operational constraints. The Spanning Tree Search algorithm is used to identify a post-outage topology that will restore the maximal amount of load with a minimal number of switching operations. The goal of the proposed tool is to determine the optimal switching sequences for the restoration process. The reliability indices incorporates contributions of all possible faults effects

Dynamic Distribution System Reconfiguration to Improve System Reliability Considering Renewables and Energy Storage

O desenvolvimento económico e o crescente uso de novas tecnologias por parte dos consumidores fazem com que o fornecimento de energia, bem como a sua qualidade, se tornem uma séria preocupação. Uma forma de abordar essa preocupação é implementando sistemas de distribuição automatizados com tecnologias inteligentes para melhorar a fiabilidade e a eficiência da operação de sistema. Os sistema eléctricos actuais estão em evolução devido às novas funcionalidades que o sistema eléctrico deverá ter, nomeadamente a integração de fontes de energia renováveis em grande escala, a integração de veículos eléctricos, a implementação de tecnologias de redes inteligentes, entre outras. Neste cenário, os Sistemas de Distribuição Inteligentes (SDI) devem operar e restaurar o serviço interrompido aos consumidores. Para que o sistema ganhe esta capacidade, é necessário substituir os interruptores manuais por interruptores controlados de forma remota, melhorando a capacidade de restauração do sistema tendo em vista a implementação de redes inteligentes. Este trabalho tem como objectivo desenvolver um novo modelo, determinando o conjunto mínimo de interruptores a substituir para automatizar o sistema, juntamente com uma análise de sensibilidade sobre a posição dos novos interruptores, que podem ser colocados no mesmo local dos substituídos ou num novo local. A optimização do sistema é feita considerando a integração de fontes de energia renováveis na rede e sistemas de armazenamento de energia, simultaneamente com os requisitos económicos e funcionais do sistema. A ferramenta computacional é testada usando o sistema de teste IEEE 119 Bus, onde são considerados vários tipos de carga (residencial, comercial e industrial).The economic development and the use of more and more technologies by the consumers make the constant energy supply and quality become a critical concern. One way to address this concern is through the implementation of automated distribution systems with intelligent technologies to improve the systems reliability and efficiency in operation. The present electrical systems are evolving due to the new functionalities that the electrical system are expected to have, namely the integration of renewable energy sources in large-scale, the integration of electric vehicles, enable smart grid technologies, among others. In this scenario, Distributed Smart Systems (DSS) should operate and restore discontinued service to consumers. In order to the system gain theses ability is necessary replace the manual switches for remotely controlled switches, improving the system restoration capability having in view the Smart Grids implementation. This paper aims to develop a new model, determining the minimal set of switches to replace in order to automate the system, along with a senility analysis on the position of the new switches, whether it should be placed in the same place as the manual switch or in a new location. The optimization of the system is made considering the renewable energy sources integration in the grid, energy storage systems simultaneously with the economic and functional requirements of the system, in order to improve the system reliability. The computational tool is tested using the IEEE 119 Bus test system to validate the new tool, where different types of load are considered (residential, commercial and industrial)

Modeling of the rural distribution system with applications of microgrids, to evaluate reliability

Modern society is faced with an unsustainable energy system. Therefore, in recent years innovative solutions have emerged in order to modernize distribution systems. The concept of Microgrids (MGs) is key within these solutions, since the implementation of these would improve the quality of supply, reliability and provide cleaner energy at lower costs. Despite its advantages, researchers in the area of MGs currently face great challenges. An example of this is the evaluation of the reliability of rural distribution systems with MGs. In this thesis, a rural distribution system with MGs was modeled, with representation in reliability parameters, using the Sequential Monte Carlo Simulation Method, with the objective of evaluating the impact on the reliability of rural distribution systems when MGs are introduced. For this, different levels of penetration of photovoltaic and conventional distributed generation systems and energy storage systems were explored. The results showed that the method proposed based on Monte Carlo computational simulation with a sequential approach and the use of real data allows the reliability evaluation of rural distribution systems with Microgrids applications, even for large-scale distribution systems that involve complex operating conditions. It was identified that, for the proposed scenarios, the inclusion of Microgrids components induce an increase in the reliability of the rural distribution system. In addition, provides information to make recommendations on the sizing of the different systems that make up MGs, with the ultimate goal of meeting specific reliability objectives. La sociedad moderna se enfrenta a un sistema energético insostenible, debido a la creciente demanda energética (se espera que se duplique en 20 años) y al envejecimiento de las actuales redes eléctricas, entre otros. Lo anterior, es más notorio en sistemas de distribución rural, especialmente en países en desarrollo, siendo esto consecuencia de ubicaciones remotas y clientes altamente dispersos conectados a redes aéreas débiles con topologías radiales sin redundancia. Para hacer frente a estos retos y muchos otros, en años recientes nace el concepto de Smart-Grids, que integra el sistema de potencia convencional con sistemas de generación distribuida convencionales o renovables, sistemas de almacenamiento de energía y vehículos eléctricos, utilizando para esto sistemas de protecciones avanzados, sistemas de control inteligentes y tecnologías de la información y las telecomunicaciones.DoctoradoDoctor en Ingeniería Industria