Control Room Requirements for Voltage Control in Future Power Systems

In future power grids, a large integration of renewable energy sources is foreseen, which will impose serious technical challenges to system operators. To mitigate some of the problems that renewable energy sources may bring, new voltage and frequency control strategies must be developed. Given the expected evolution of technologies and information systems, these new strategies will benefit from increasing system observability and resources controllability, enabling a more efficient grid operation. The ELECTRA IRP project addressed the new challenges that future power systems will face and developed new grid management and control functionalities to overcome the identified problems. This work, implemented in the framework of ELECTRA, presents an innovative functionality for the control room of the cell operator and its application in assistance with the voltage control designed for the Web-of-Cells. The voltage control method developed uses a proactive mode to calculate the set-points to be sent to the flexible resources, each minute, for a following 15-min period. This way, the voltage control method developed is able to mitigate voltage problems that may occur, while, at the same time, contributes to reduce the energy losses. To enable a straightforward utilization of this functionality, a user interface was created for system operators so they can observe the network state and control resources in a forthright manner accordingly.The work presented in this paper was funded by the ELECTRA IRP project (Seventh Framework Programme FP7 2007/2013) under grant agreement No. 609687

Dynamic security assessment by fuzzy inference

This paper reports an experience on the application of fuzzy reasoning to the fast assessment of the dynamicsecurity of an isolated power system with high wind power penetration. The inference method is a TakagiSugenotype system with a small number of rules, optimized for each specific learning set by a standard methodincluded in the MATLAB Fuzzy Logic Toolbox. The methodology is demonstrated in a contingency study in thenetwork of Crete that showed good results in the test set. The paper discusses some implementation issues andpossible future developments of the approach

A non-recurrent inferior laryngeal nerve in a man undergoing thyroidectomy: a case report

<p>Abstract</p> <p>Introduction</p> <p>A non-recurrent variant of the inferior laryngeal nerve has been seldom reported. These reports are mostly based on cadaveric dissection studies or large chart review studies in which the emphasis is placed on the determination of the frequency of the variation, and not on the clinical appearance of this variant. We graphically describe the intraoperative identification of a non-recurrent inferior laryngeal nerve.</p> <p>Case Presentation</p> <p>A 44-year old Caucasian man was referred to the Head and Neck Surgery Outpatient Clinic with the diagnosis of a nodular mass in his left thyroid lobe that had been growing for one year. A fine needle aspiration puncture was compatible with thyroid papillary cancer. It was decided that the patient should undergo total thyroidectomy. During surgery, a non-recurrent right inferior laryngeal nerve was noted. This nerve emanated from the right vagus nerve, entering the larynx 3 cm after its origin. The nerve did not show a recurrent course. The nerve on the left side had a normal configuration. The surgery and post-operative period were uneventful, and the patient had no change in his voice.</p> <p>Conclusion</p> <p>This paper allows those interested to become acquainted with the normal intraoperative appearance of a non-recurrent inferior laryngeal nerve. This will undoubtedly be of significance for all of those performing invasive diagnostic and surgical procedures in the neck and upper thoracic regions, in order to minimize the risk of iatrogenic injury to this nerve. This is of extreme importance, since a unilateral lesion of this nerve may result in permanent hoarseness, and a bilateral lesion may lead to aphonia and life-threatening dyspnea.</p

Flexibility Assessment of Multi-Energy Residential and Commercial Buildings

With the growing concern about decreasing CO 2 emissions, renewable energy sources are being vastly integrated in the energy systems worldwide. This will bring new challenges to the network operators, which will need to find sources of flexibility to cope with the variable-output nature of these technologies. Demand response and multi-energy systems are being widely studied and considered as a promising solution to mitigate possible problems that may occur in the energy systems due to the large-scale integration of renewables. In this work, an optimal model to manage the resources and loads within residential and commercial buildings was developed, considering consumers preferences, electrical network restrictions and CO 2 emissions. The flexibility that these buildings can provide was analyzed and quantified. Additionally, it was shown how this model can be used to solve technical problems in electrical networks, comparing the performance of two scenarios of flexibility provision: flexibility obtained only from electrical loads vs. flexibility obtained from multi-energy loads. It was proved that multi-energy systems bring more options of flexibility, as they can rely on non-electrical resources to supply the same energy needs and thus relieve the electrical network. It was also found that commercial buildings can offer more flexibility during the day, while residential buildings can offer more during the morning and evening. Nonetheless, Multi-Energy System (MES) buildings end up having higher CO 2 emissions due to a higher consumption of natural gas

EMPOWERING THE SYSTEMS ENGINEER -IEC 61850 AND VISUAL LANGUAGES

ABSTRAC

Holistic Framework to Data-Driven Sustainability Assessment

In recent years, the Twin-Transition reference model has gained notoriety as one of the key options for decarbonizing the economy while adopting more sustainable models leveraged by the Industry 4.0 paradigm. In this regard, one of the most relevant challenges is the integration of data-driven approaches with sustainability assessment approaches, since overcoming this challenge will foster more agile sustainable development. Without disregarding the effort of academics and practitioners in the development of sustainability assessment approaches, the authors consider the need for holistic frameworks that also encourage continuous improvement in sustainable development. The main objective of this research is to propose a holistic framework that supports companies to assess sustainability performance effectively and more easily, supported by digital capabilities and data-driven concepts, while integrating improvement procedures and methodologies. To achieve this objective, the research is based on the analysis of published approaches, with special emphasis on the data-driven concepts supporting sustainability assessment and Lean Thinking methods. From these results, we identified and extracted the metrics, scopes, boundaries, and kinds of output for decision-making. A new holistic framework is described, and we have included a guide with the steps necessary for its adoption in a given company, thus helping to enhance sustainability while using data availability and data-analytics tools

:Estúdio, nº31 (Jul./Set. 2020)

A propósito dos 14 artigos apresentados no N. 31 da Revista Estúdio, apresenta-se uma perspetiva sintética e interrogadora sobre as formas da arte, interrogando a sua ancoragem agarrada à subjetividade. Esta entidade desfaz-se como ponto de vista, mas permite a representação, para uma abstração estética. A Arte na mole dos tempos é então uma forma agarrada a uma perspetiva, uma imagem na retina semantizada. O contexto é de perigo, na emergência ambiental, expondo uma arte que pode ser doente, com o mal reificado do capital. O desafio é alto, para uma superação na Arte contemporânea.info:eu-repo/semantics/publishedVersio