Cookies Policy
We use cookies to improve our site and your experience. By continuing to browse our site you accept our cookie policy. Find out More
Close
  • Menu
Interest
Topics
Details

Details

  • Name

    Nuno José Gil
  • Cluster

    Power and Energy
  • Role

    External Research Collaborator
  • Since

    01st July 2003
Publications

2011

Hierarchical Frequency Control in Multi-MicroGrids: The Participation of Electric Vehicles

Authors
Nuno Gil; Diego Issicaba; Pedro Rocha Almeida; João Peças Lopes

Publication
CIGRÉ SYMPOSIUM - Cigrè International Symposium , Bologna, Italy

Abstract
The operation and planning of Low Voltage (LV) and Medium Voltage (MV) distribution networks have been changing over the last decade. Due to the presence of Distributed Generation (DG) and microgeneration, an active role has been attributed to these networks in grid operation. For this accomplishment, different conceptual approaches were developed. In [1], a hierarchical control structure was defined, considering that DG units, onload tap changer transformers, static var compensators and loads can be controlled by a hierarchically higher entity, the Central Autonomous Management Unit (CAMC). The CAMC is also responsible for the management of specific LV networks, the MicroGrids (MG), which in turn have autonomy to manage their loads and microgeneration units through an entity called MicroGrid Central Controller (MGCC). A MV grid with these characteristics plus some storage devices would then be called a Multi-MicroGrid (MMG), being, among other functionalities, able to operate isolated from the upstream network. The recent appearance of a new type of load to the system, the Electric Vehicle (EV), expected to be largely integrated in the electricity grids in the upcoming years, has a great potential for adding controllability to the MMG. In this paper, an EV control droop (see [2]) will be introduced to improve the MMG performance when EVs operate as active elements. EV controllers are then able to receive setpoints from the CAMC and also actively update the droop settings in

2011

Impact of Multi-Microgrid Communication Systems in Islanded Operation

Authors
David Emanuel Rua; Luís Filipe Pereira; Nuno José Gil; João Peças Lopes

Publication
ISGT 2011 - IEEE PES ISGT 2011 Europe , Manchester, UK

Abstract

2011

Service restoration on distribution systems using Multi-MicroGrids

Authors
Fernanda Resende; Nuno Gil; Peças Lopes

Publication
ETEP - European Transactions on Electrical Power, vol.21, no.2, pp.1327-1342

Abstract
Large scale integration of distributed generation of both medium and low voltage networks can be achieved by exploiting the Multi-MicroGrid (MMG) concept, a new distribution system architecture comprising a hierarchical control system, which allows the coordination among distributed generation units and MicroGrids and therefore the operation of such a system in islanded mode. After a general blackout the MMG capabilities can also be used to provide service restoration in distribution systems. A new procedure for MMG black start is then addressed in this paper. A sequence of control actions is defined and evaluated through numerical simulations. Fully automation of the entire MMG black start procedure is discussed along the paper. The results obtained demonstrate the feasibility of the proposed sequence of control actions and highlight some accomplishments that should be considered in order to successfully restore the MMG service, ensuring system stability and power quality.

2011

Advanced Control and Management Functionalities for Multi-MicroGrids

Authors
André Madureira; Jorge Pereira; Nuno Gil; João Peças Lopes; George Korres; Nikos Hatziargyriou

Publication
ETEP - European Transactions on Electrical Power, vol.21, no.2, pp.1159-1177

Abstract
This paper addresses the extension of the Microgrid concept, following a massive integration of these active cells in power distribution networks, by adopting a coordinated management strategy together with Distributed Generation units directly connected to the Medium Voltage distribution network. In order achieve this, a technical and commercial management scheme must be developed for coordinated control of a distribution system with Multi-Microgrids, which should take into account the specific technical capabilities and characteristics of each type of generating source. In particular, tools for coordinated voltage support and frequency control, as well as for state estimation have been developed for this type of networks. Concerning voltage support, a new methodology exploiting an optimization tool based on a meta-heuristic approach was developed. For state estimation, two approaches were considered: Multi-Microgrid State Estimation and Fuzzy State Estimation. Regarding frequency control, the hierarchical structure of the Multi-Microgrid is exploited to deal with the transition to islanded operation and load following in islanded operation. All these tools have proved to be efficient in managing the Multi-Microgrid system in normal interconnected mode and, in case of the frequency control, in islanded operation.

2010

Identificação de condições de Operação em Modo Isolado e Procedimentos de Controlo de Emergência para Multi-micro-redes

Authors
Nuno José Gil

Publication
PhD Thesisvol.0

Abstract