Integration of a microgrid laboratory into an aggregation platform and analysis of the potential for flexibility

The increase of Renewable Energy Sources (RES) has given momentum to demand-side flexibility, led by Demand Response (DR), to counteract the uncertainties of the new electricity system. Meanwhile, consumers, with the help of Demand Aggregators (DA), are becoming active participants by engaging in flexibility actions. As a tool for the experimental assessment of DR, this work integrates a microgrid laboratory with an aggregation platform. To test the environment created and analyse the impact of DR, two consumers have been defined using virtual, emulated and real elements: a residential user with a Heating Ventilation and Air Conditioning (HVAC) unit and a prosumer equipped with Photovoltaic (PV) panels and a second-life battery.Postprint (published version

Control of a utility connected microgrid

This paper describes the control algorithm of a utility connected microgrid, based on independent control of active and reactive power (PQ control) and working in centralized operation mode. The microgrid under investigation is composed of three configurable units: a generation unit, a storage unit and a load. These units are interfaced with the microgrid through a Voltage Source Converter (VSC) and are controlled by the nodes of the communication system by means of IEC 61850. A set of tests have been conducted to evaluate the microgrid behavior.Postprint (published version

Renewable medium-small projects in Spain: Past and present of microgrid development

This paper reviews the on-going research studies and microgrid pilot projects focusing on the Spanish case because of its renewable energy potential with the objective set on highlights the main investigation drifts in the field such as the used technologies, control methods and operation challenges. That way, several smart grids have been commented and compared, finding that photovoltaic and wind power are the favourites energy generation technologies. Although batteries are the most widespread energy storage systems, green hydrogen has a strong presence, showing up in a third of the Spanish smart grids. Traditional control strategies are being displaced by advanced ones such as MPC or fuzzy logic due to its higher efficiency. The reader will have a clear view of the potential of renewable energy penetration in the form of smart grids in Spain, through the study of the equipment involved in the different facilities contribution and the main control strategies implemented, in a comparative analysis of the key aspect of this emerging technology.Consejería de Conocimiento, Investigación y Universidad - Junta de Andalucía PY18-RE-002

Design, management and comissioning of a utility connected microgrid based on IEC 61850

This paper presents an approach to microgrid automation. The microgrid is composed of three different nodes connected to the public electric grid, which are hardware emulated with back-to-back converters. The microgrid is a flexible and weather independent test bed for testing different control algorithms. The intelligence of the automation system is split in three hierarchical layers: the RMU layer, the iNode layer and the iSocket layer. Communications among iNode and iSockets are according IEC 61850 standard. The aims of the project is to comission a set of technologies and acquire experience in microgrid automation, IEC 61850 communications and power control algorithms in DER systems

Design and implementation of a supervisory control and data acquisition system (SCADA) for a microgrid laboratory

This report presents the work conducted as a master thesis project within SmartLab laboratory of the Catalonian Institute for Energy Research (IREC). The focus of the work is on the design and development of a Supervisory Control and Data Acquisition (SCADA) system for the Institute?s laboratory microgrid system. Based on the pre-defined requirements, a comprehensive system has been built being prepared to configure and manage the local controllers of laboratory cabinets. As a showcase of the designed system, an example of residential autoconsumption has been emulated. Differences are pointed out with simulations by a comparative analysis between the showcase emulation and simulation in Matlab 2014a. Finally, a business idea is proposed with the active participance of the discussed technology. The microgrid and the developed SCADA are based on the needs of forthcoming projects of the Institute

Sistema multiagente para proteção adaptativa de microrredes

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Elétrica, Florianópolis, 2014.A integração de geradores conectados nas redes de distribuição de energia, também chamada de Geração Distribuída (GD), pode gerar dificuldades para a operação e controle, pois altera características tradicionais destes sistemas. Estas dificuldades podem ser em parte resolvidas nas chamadas microrredes, que são subsistemas da rede de distribuição de energia, cuja principal característica é a capacidade de operar em condições de ilhamento, ou seja, separadas da rede principal de distribuição de energia elétrica. Entretanto, as microrredes também trazem consigo desafios a serem resolvidos, um deles diz respeito à proteção, especificamente à sensibilidade e coordenação de relés com funções de sobrecorrente. Assim, neste trabalho é proposta uma arquitetura de Sistema Multiagente (SMA) para realizar a proteção adaptativa de microrredes baseada em relés com função direcional de sobrecorrente instantânea e temporizada. Para implementação do protótipo foi utilizada a plataforma JADE (Java Agent Development Framework), juntamente com uma biblioteca em JAVA para desenvolvimento de Sistemas Especialistas (SE), chamada CLIPSJNI (Java Native Interface for C Language Integrated Production System). Na arquitetura proposta, é descrito o papel que cada um dos agentes desempenha na proteção, sua hierarquia e a troca de mensagens entre agentes para execução da tarefa a ser realizada - isto é, mudança nos ajustes de configuração dos relés (análise off-line) ou detecção e eliminação de faltas (análise on-line). Simulações de faltas no software PSCAD/EMTDC (Power System Computer Aided Design/Eletromagnetic Transients Including DC) foram realizadas para parametrizar os agentes do sistema e também para verificar a viabilidade da proposta. Finalmente, os resultados obtidos são discutidos e atestam a eficiência da metodologia desenvolvida.Abstract: The integration of generators connected to power distribution networks, also called Distributed Generation (DG), alters traditional features of these systems and may cause difficulties for their operation and control. These difficulties can be partly resolved by microgrids, which are subsystems of the power distribution network, whose main feature is the ability to operate in islanding conditions, i.e., separated from the main distribution network. However, microgrids also bring challenges to besolved, one of them concerns the protection, specifically the sensitivity and coordination of overcurrent relays. In this context, this dissertation proposes an architecture of Multi-Agent System (SMA) to perform adaptive protection of microgrids based on directional time and instantaneous overcurrent functions. For the implementation of the prototype JADE (Java Agent Development Framework) platform was used, along with a library in Java for Expert Systems (SE), called CLIPSJNI (Java Native Interface for C Language Integrated Production System). The hierarchy between agents in the proposed architecture and the role played by each protecting agent is described. Examples of messages exchanged between agents to perform tasks such as change of relay settings (off-line analysis) or detection and elimination of faults(on-line analysis) are presented. Simulations of faults inPSCAD/EMTDC (Power System Computer Aided Design /Electromagnetic Transients Including DC) are performed to parameterize the agents of the system and also to verify the feasibility of the proposal. Finally, the results obtained are discussed and testify the efficiency of the developed methodology