Alex Reis

Dr. Alex Reis

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Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 December 2024 in Sustainability
Verified
Journal Article
Open access
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PFPaulo Fernandes
Paulo Fernandes
ARAlex Reis
Alex Reis
LVLoana N. Velasco
Loana N. Velasco
TFTânia M. Francisco
Tânia M. Francisco
EREnio Costa Resende
Enio Costa Resende
LUIZ CARLOS GOMES FREITASLUIZ CARLOS GOMES FREITAS
LUIZ CARLOS GOMES FREITAS
This work presents the results of research aimed at evaluating the performance of the photovoltaic system connected to the electrical grid at the University of Brasília (UnB), Brazil. Following the guidelines established by the Brazilian Standard for Performance Monitoring and Analysis of Grid-connected Photovoltaic Systems, it was possible to evaluate the system’s performance by determining the Performance Ratio (PR) indicator. The operating temperatures were estimated using measured values of the ambient temperature and solar irradiation. These data were collected by a nearby solarimetric station. Next, the theoretical energy injected into the electrical grid was determined based on calculations of the Direct Current (DC) power at the inverter input and the Alternating Current (AC) power at the inverter output. To this end, the coefficients of the inverter efficiency curve were considered as well as a loss scenario, as recommended. With these results, as well as the information about the total photovoltaics (PV) system AC production obtained from the inverter supervisory system, it was possible to determine the average annual PR achieved and compare the theoretical and practical results obtained. The main contribution of this paper is the performance evaluation of a 125 kWp grid-connected photovoltaic system at the University of Brasília (UnB), assessed using Brazilian Standards for performance monitoring and analysis. The system, installed on the rooftop of the UED building, consists of 298 Canadian Solar HiKu CS3W-420P modules with a 15-degree north pitch angle facing geographic north. It interfaces with the grid through two three-phase inverters, model CSI-75K-T400 (74.76 kWp) and a CSI-50KTL-GI (50.4 kWp). The results showed that the system with a 50kW inverter had an average PR of 78%, while the system with a 75 kW inverter showed a PR variation from 56% to 93%. The information obtained in this work will be used to develop computational tools capable of monitoring and evaluating, in real time, the performance of photovoltaic systems and ensuring that the expected financial return is achieved through the use of preventive and corrective maintenance actions in a timely manner.

29 November 2021 in International Transactions on Electrical Energy Systems
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Journal Article
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PMPedro Moraes
Pedro Moraes
ARAlex Reis
Alex Reis
AFAnésio de Leles Ferreira Filho
Anésio de Leles Ferreira Filho

5 July 2024 in Electric Power Systems Research
Verified
Journal Article
Closed access
ARAlex Reis
Alex Reis
AFAnésio de L.F. Filho
Anésio de L.F. Filho
PMPedro H.F. Moraes
Pedro H.F. Moraes
JLJuliana P. de Lima
Juliana P. de Lima
MNMohamad S.I. Neto
Mohamad S.I. Neto
VPVinícius dos Passos
Vinícius dos Passos

20 July 2025
Verified
Conference Paper
Open access
PDF file
IAIsaque Alves
Isaque Alves
JEJoão Egewarth
João Egewarth
LBLaila Bellix
Laila Bellix
ARAlex Reis
Alex Reis
CRCarla Rocha
Carla Rocha
Este artigo apresenta o relato de experiência na implementação de uma plataforma open source para integrar dados de diferentes Sistemas Estruturantes da execução orçamentária federal (SIOP, SIAFI, SIAPE, TransfereGov e ContratoGov). Diante da dificuldade de promover interoperabilidade entre sistemas geridos por diferentes órgãos, adotou-se uma abordagem orientada por dados, baseada na arquitetura Medallion. A solução permite a geração automatizada de relatórios, governança descentralizada e mapeamento de requisitos para futura interoperabilidade. Como resultado, oferece uma alternativa escalável e reutilizável, com dados centralizados, APIs documentadas e dashboards interativos, além de lições aprendidas sobre a qualificação de processos e a melhoria da gestão pública.

1 January 2026 in IEEE Access
Verified
Journal Article
Open access
GVGustavo Gomes Do Valle
Gustavo Gomes Do Valle
BSBenjamin Soudhan
Benjamin Soudhan
MMMeisam Mahdavi
Meisam Mahdavi
ARAlex Reis
Alex Reis
AFAnésio de Leles Ferreira Filho
Anésio de Leles Ferreira Filho
RGRaphael Gomes
Raphael Gomes

15 July 2025 in Energies
Verified
Journal Article
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ARAlex Reis
Alex Reis
JOJosé Carlos De Oliveira
José Carlos De Oliveira
CGCarlos Alberto Villegas Guerrero
Carlos Alberto Villegas Guerrero
JOJohnny José Orozco
Johnny José Orozco
LMLúcio José Motta
Lúcio José Motta
JMJosé Mauro Teixeira Marinho
José Mauro Teixeira Marinho
Driven by the environmental benefits associated with reduced greenhouse gas emissions, oil companies have intensified research efforts into reassessing the strategies used to meet the electrical demands of offshore production platforms. Among the various alternatives available, the deployment of onshore–offshore interconnections via High-Voltage Direct Current (HVDC) transmission systems has emerged as a promising solution, offering both economic and operational advantages. In addition to reliably meeting the electrical demand of offshore facilities, this approach enables enhanced operational flexibility due to the advanced control and regulation capabilities inherent to HVDC converter stations. Based on the use of interconnection through an HVDC link, aiming to evaluate the operation of the electrical system as a whole, this study focuses on evaluating dynamic events using the PSCAD software version 5.0.2 to analyze the direct online starting of a large induction motor and the sudden loss of a local synchronous generating unit. The simulation results are then analyzed to assess the effectiveness of both Grid-Following (GFL) and Grid-Forming (GFM) control strategies for the converters, while the synchronous generators are evaluated under both voltage regulation and constant power factor control operation, with a particular focus on system stability and restoration of normal operating conditions in the sequence of events.