07Sep 2021 by admin No Comments
Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output? (2021)

Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output? (2021)

EEf
Research topic: Photovoltaic SystemOperation&Maintenance Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output? Hamid Iftikhar, Eduardo A. Sarquis Filho, P. J. da Costa BrancoMDPI Energies (2021)(Check article) Short Abstract: In this paper, a comparative analysis is done using real field data and simulation to assess the PV power plant underperformance and indicates the most important predictive maintenances actions. Issues in the tracking systems, inverters and combiner boxes were reported. In addition, an analysis of the O&M power plant reports was performed and compared to the best global practices. In this case, the adoption of predictive maintenance and automated plant diagnosis at the strings level were recommended. Additional content:
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07Sep 2021 by admin No Comments
A complete framework for the simulation of photovoltaic arrays under mismatch conditions (2021)

A complete framework for the simulation of photovoltaic arrays under mismatch conditions (2021)

EEf
Research topic: Photovoltaic SystemModelling A complete framework for the simulation of photovoltaic arrays under mismatch conditions Eduardo A. Sarquis Filho, Carlos A. F. Fernandes, P. J. da Costa BrancoElsevier Solar Energy (2021)(Check article) Short Abstract: This paper introduces a complete a simulation framework capable of reproduce mismatch conditions at the cell level, including failures. The results were validated experimentally for mismatch conditions due to shading but also due to failures. The simulation framework is more suitable to emulate small arrays with few strings, being a helpful tool for the study of failure impacts on PV strings.
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10Aug 2021 by admin No Comments
VIENA – Veículo Inteligente Elétrico de Navegação Autónoma

VIENA – Veículo Inteligente Elétrico de Navegação Autónoma

Project
Research topic: Electric Vehicles VIENA - Intelligent Electric Vehicle with Autonomous Driving (Veículo Inteligente Elétrico de Navegação Autónoma)Internal project of E2TES Objectives: To develop a learning platform for the DEEC students regarding vehicles with electric and autonomous capabilities; The entire project is aimed to be for students and developed and improved by students. All parts of the project are to be open and free, accessible to all students from around the world. https://www.youtube.com/watch?v=w1iibaJBaag Check more here! Works developed by this team: Autonomous drivingSpeed Control TestSteering Control Teshttps://www.youtube.com/watch?v=w1iibaJBaaghttps://youtu.be/304CCp7y9Lkhttps://youtu.be/KB9a7eYezl0Simulation Model (LINK)
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10Aug 2021 by admin No Comments
REDAWN – Reducing Energy Dependency in Atlantic Area Water Networks, Program Interreg, EU (2016-2021)

REDAWN – Reducing Energy Dependency in Atlantic Area Water Networks, Program Interreg, EU (2016-2021)

Project
Research topic: Energy Recovery REDAWN – Reducing Energy Dependency in Atlantic Area Water Networks P.I.: prof. Helena Ramos (IST coordinator)Collaboration of Prof. Paulo Branco and Prof. João FernandesFunded by Interreg Program, EU Objectives: Completion of an energy recovery resource assessment in water networks in the Atlantic Area; Completion of an economic/environmental impact assessment of this technology on the region; Development of design guidelines and support tools for hydropower energy recovery in drinking water, waste-water, irrigation and process industry sectors; Development of policy and institutional support tools to increase the implementation of energy recovery projects; Quantification of the societal impacts of hydropower energy recovery in water networks, and; Widespread dissemination and promotion of energy efficiency in Atlantic Area water networks. Works developed by this team: Electric behavior of the Pump working…
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10Aug 2021 by admin No Comments
YBCO Superconducting Blocks Inserted in Electromechanical Systems (2016-2019)

YBCO Superconducting Blocks Inserted in Electromechanical Systems (2016-2019)

Project
Research topic: Superconductors YBCO Superconducting Blocks Inserted in Electromechanical Systems P.I.: Prof. Paulo José da Costa BrancoFunded by FCT: PTDC / EEI-EEL / 4693/2014. From April 22, 2016 to April 21, 2019. Funding of € 112,072.00. Objectives: This research project focused on the modelling and application of HTS bulk in electromechanical systems. The main task performed were:1) Formulation of a distributed parameter model of YBCO  for simulation of electromagnetic and thermal properties. 2) Study of the in-loco pulsed magnetization process of the YBCO superconductor cooled to 77K: the number of pulses required for the magnetization of the material;3) Selection of optimized magnetic circuit topology for a low-speed generator; 4) Development and testing of a prototype of the low-speed generator.  Developed works: In-loco HTS magnetization processZero-Field-Cooled Superconducting Levitation BearingHTS Electromagnetic and Thermal Modelling…
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08Aug 2021 by admin No Comments
Use of Bulk Superconductors in the Excitation System of Low-Speed Synchronous Generators (2021)

Use of Bulk Superconductors in the Excitation System of Low-Speed Synchronous Generators (2021)

EC, NMM
Research topic: SuperconductorsModelling 3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces João Arnaud; João F. P. Fernandes, Paulo J. Costa BrancoJournal: IEEE Transactions on Applied Superconductivity (2021)(Check this article) Short Abstract: This work focuses on implementing HTS bulks in the excitation circuit of low-speed synchronous generators as permanent magnets. To reduce the maintenance costs and time required for the magnetization process, an in-loco remagnetization is used. The HTS bulks are magnetized in their position inside the machine's magnetic circuit. A pulse-field magnetization (PFM) technique is used, using the stator coils of a linear generator. The experimental procedure starts with the in-loco PFM to magnetize the HTS bulks and, by applying an oscillatory movement to the linear generator's moving part, measuring the magnetic flux density induced voltage is…
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08Aug 2021 by admin No Comments
Transient study of series-connected pumps working as turbines in off-grid systems (2021)

Transient study of series-connected pumps working as turbines in off-grid systems (2021)

EEf
Research topic: Pump as TurbinesSeries Transient study of series-connected pumps working as turbines in off-grid systems Margarida C. Pagaimo, João F. P. Fernandes, ModestoPérez-Sánchez, P. Amparo López-Jiménez, Helena M. Ramos, P. J. Costa Branco Energy Conversion and Management (2021) (Check article) Short Abstract: This paper contributes for a further study and application of off-grid PAT (pump-as-turbine) systems to be installed in water distribution systems, for both rural or remote areas. This paper assesses the reliability of associating multiple groups of PAT systems in series, each connected to a self-excited induction generator (SEIG). This is an important topic that could lead to more cost-effective solutions and allow the series association of different users. This work is a follow-up of an international collaboration between the University of Lisbon and Universitat Politecnica de…
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30Jul 2021 by admin No Comments
Cobalt Iron Core Impact on Optimal Design of an Interior Permanent Magnet Synchronous Motor for Competition Electric Vehicle (2020)

Cobalt Iron Core Impact on Optimal Design of an Interior Permanent Magnet Synchronous Motor for Competition Electric Vehicle (2020)

EC, NMM
Research topic: Cobalt IronModelling Cobalt Iron Core Impact on Optimal Design of an Interior Permanent Magnet Synchronous Motor for Competition Electric Vehicle Pedro P. C. Bhagubai; António C. Cardoso; João F. P. FernandesConference: Global Power, Energy and Communication Conference (GPECOM) (2020)(Check this article) Short Abstract: To analyze the impact of cobalt iron cores in the design of interior permanent magnet synchronous motors (IPSM) for competition electric vehicles, a spoke-type IPSM geometry is optimized considering FeSi and VaCoFe cores. It is shown that machines with VaCoFe core are a better alternative across both considered torque and efficiency ranges. VaCoFe can result in an estimated increase of up to 3% in efficiency for the same torque, or up to 70% torque increase for the same efficiency level. Additional content: Optimized variables Torque-efficiency curves for…
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30Jul 2021 by admin No Comments
3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces (2021)

3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces (2021)

NMM
Research topic: SuperconductorsModelling 3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces Inés S. P. Peixoto; F. Ferreira da Silva; João F. P. Fernandes; P. J. da Costa Branco (copy-past the authors from IEEE site, it comes with links)Journal: IEEE Transactions on Applied Superconductivity (2021)(Check this article) Short Abstract: This paper proposes a novel methodology for calculating a space-varying permeability in HTS bulks, ensuring the same magnetic energy stored in E-J models at each infinitesimal volume, for the electromagnetic force calculation in HTS bulks.  The proposed method was validated using simulation and experimental tests based on YBCO/GdBCO permanent-magnet force interactions. These results show that, with a previous general study of the geometry to optimize, the equivalent model can be used for optimization purposes, greatly reducing the computational time. Additional content:…
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