Engenharia Elétrica (UACSA)

URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/2922

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APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso

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Agora exibindo 1 - 20 de 37

Impactos da inserção de geração distribuída no desempenho de funções de proteção de sistemas elétricos
(2019-07-17) Guerra, Keylla Rayanne Albuquerque; Reis, Raphael Leite de Andrade; http://lattes.cnpq.br/1139577841043865; http://lattes.cnpq.br/8938549432716009
From the need to expand the electric generation due to population and industrial growth, the connection of Distributed Generation (DG) with the electrical system has increased due to its several advantages, such as: minimization of transmission losses over long distances, location near consumer centers, minimizing environmental impacts and greater reliability. Despite being a trend, challenges to the protection system are imposed as contributions to short circuit currents may become more evident with the GD connection. In order to investigate the impact of GD on electrical power system protection functions, fault simulations were performed in the Alternative Transients Program (ATP) software, considering a 230 kV network reported in the literature. Short circuits were simulated along the evaluated power system as well as near the distance protection zone reaching, taking into account different types of disturbances. From the obtained results, the insertion of GD can affect the voltage and current signals measured by the protective device, as well as protection functions, leading them to misoperate if revisions on their adjustment settings are not performed.
Impacto da medição de sinais de tensão em métodos de localização de curtos-circuitos baseados no domínio do tempo
(2019-12-12) Silveira, Mirella Ilka Pereira da; Reis, Raphael Leite de Andrade; http://lattes.cnpq.br/1139577841043865; http://lattes.cnpq.br/0341519550011359
In this work, the impact of voltage measuraments on the performance of traveling wave-based fault location functions is evaluated. Basically, one- and two-ended fault location algorithms were implemented in Matlab, being the voltage and current measurements used as data input for the routines taken from a coupling capacitive voltage transformer (CCVT) and a current transformer (CT), respectively. The performance of the fault location techniques is investigated by several short-circuit simulations in a 230 kV electrical power system, considering variations in the fault parameters such as resistance and inception angle. The CCVT dynamic response is also token into account, especially in the one-terminal routine, which is rarely reported in the literature. From the obtained results, it can be seen that the two-terminal algorithm has shown to be more robust, since more information about the power network is used as input data, although it depends on a communication path. Regarding the one-terminal function, the CCVT dynamic response end may change the wave polarities detected at the monitored end, which affects the technique if ways to compensate the CCVT frequency response are not available.
Técnica de modulação vetorial aplicada no acionamento de máquinas elétricas trifásicas com enrolamentos abertos para minimização da tensão de modo comum
(2020-11-04) Magalhães, Raíssa Maria Lacerda; Silva, Italo Roger Ferreira Moreno Pinheiro da; http://lattes.cnpq.br/7618299953557040; http://lattes.cnpq.br/6240974108146381
In power electronics, the study of modulation techniques and topology of converters are widely used in industrial applications for driving electrical machines. In this context, research is always looking for improvements, in general, in the quality of the system, whether increasing efficiency, performance or machine life. The topology of a conventional converter as well as the pulsewidth modulation technique is the basis for the development of the studied system. So, its characteristics and relationships were taken in consideration for the development of the model. Thereby, a study was realized on a drive system for electrical machines with open winding terminals from two conventional converters. For the driving, a modulation technique based on the vector analysis of the switching states was proposed to minimize the common-mode voltage. Besides that, a simulation was realized, considering ideal conditions to validate the described technique and the results presented the minimization of the common mode voltage based on the choice of certain switching states.
Estudo de modelo e controle vetorial orientado pelo fluxo estatórico de motor de indução trifásico para propulsão de veículos elétricos
(2020-11-06) Azevedo, Pedro Paulo Oliveira Costa de; Silva, Italo Roger Ferreira Moreno Pinheiro da; http://lattes.cnpq.br/7618299953557040
The speed control of three-phase induction motors is essential for the operation of electric vehicles. Therefore, the study of the machine mathematical model for the development of simpler and more effcient methods for the control of motor parameters is important for technological development and reduction in the costs of building electric vehicles. In this project, the study of the mathematical model for the analysis of the behavior of an electric induction motor was carried out and a eld oriented control strategy was developed that uses mathematical transformations and changes of reference of the measurable quantities in an induction machine and, from this strategy, a simulation was developed. The transient and permanent response of the electromagnetic fux, conjugate, speed and electric currents obtained in the simulated environment show the reaction of the model of the induction machine with the control proposed in this work, accelerating from inertia to near to the rated speed and the elimination of the disturbance caused by the insertion of the rated mechanical torque on the motor shaft. Thus, the simulation results presented validate the theoretical considerations and show the effectiveness of the proposed control strategy, enabling its use for future studies by the UFEPE-UACSA formula SAE team.
Estudo dos principais aspectos de manutenção em sistema fotovoltaicos on-grid
(2021-03-04) Conrado, Deyvison Muniz; Araújo, Marcel Ayres de; http://lattes.cnpq.br/0669410110930611; http://lattes.cnpq.br/8030937685280342
The diversification of the Brazilian electric matrix represents a gain in reliability and availability of electricity. In this context, renewable energies have played an increasingly important role in the Brazilian energy sector. Photovoltaic solar energy, in particular, has grown considerably in recent years. One of the factors that contribute to the growth in the use of solar energy is the energy compensation system, which allows grid-connected photovoltaic plants to generate energy credits used for decreasing the bills of plant owners. Along with the increase of installations, there is also a growing demand for preventive and corrective maintenance for these systems. However, few professionals and integrating companies provide consistent maintenance plans for photovoltaic systems, or even know best practices for performing the proper procedures, which represents a problem of reliability, safety and profitability of these systems. In this sense, this work aims to discuss the maintenance of small grid-connected photovoltaic systems, commenting from the project up to the installation of the system, highlighting the relationship of these steps with some aspects of maintenance. Good preventive maintenance practices are described, as well as the relationship between plant maintenance and productivity. Finally, case studies are carried out, in which the importance of implementing appropriate procedures in the installation, operation and maintenance of photovoltaic systems can be assessed.
Impactos do dimensionamento da corrente de magnetização de transformadores na coordenação de funções de proteção de sistemas elétricos
(2021-07-09) Santos Júnior, Edivaldo Ferreira dos; Reis, Raphael Leite de Andrade; http://lattes.cnpq.br/1139577841043865; http://lattes.cnpq.br/5627386501763054
The impact of transformers’ inrush currents on overcurrent protection functions is evaluated in this work. To do so, simulation tests are carried out in power systems reported in the literature as well as in real distribution networks located in the region of Petrolina– PE. Basically, the power grids are simulated in the ANAFAS software, in which the three-phase and single line to ground fault currents are computed. These short circuit current values are used as input data in the OCTAVE software to set the instantaneous- and the time-overcurrent protection functions, as well as the transformer’s inrush cur- rent. The overcurrent functions outputs are provided to the user as the utility and consumer time-characteristic curves, indicating also the respective inrush current point in the same plot. From the obtained results, the transformer’ inrush current can directly impact on the overcurrent protection coordination, affecting the protection studies of companies fed by transformer units. In these cases, the incorrect set of such magne- tizing current influence on the protection system reliability, and it may also lead to the protection study disapproval by the utility.
Estudo comparativo de formas de onda 5G: uma análise de eficiência
(2021-07-30) Pereira, Clariele de Almeida; Paula, Amanda Souza de; http://lattes.cnpq.br/5652100307143041; http://lattes.cnpq.br/2994534149511553
This work presents the main characteristics of 5G, such as the 5G technology standardization and evolutions in relation to pre-existing technologies, focusing on the comparative analysis of FBMC and OFDM modulation techniques. The waveform is a very important component in telecommunications technologies, as they can modify the characteristics of the signal to be transmitted in the most convenient way for a given requirement. To perform the comparative analysis between the waveforms, the power spectral density vs normalized frequency and bit error rate vs signal-to-noise ratio graphs for different scenarios were simulated with the MATLAB software, such as: insertion of error variance in the channel estimation, changing the type of channel and the number of FFT elements. With these results, it is possible to see the advantage of FBMC in relation to the use of spectrum, as well as the problem of the greater complexity of the equalization system of this waveform when compared to that used in OFDM.
Construção de sistema de travamento de frequência para laser de diodo
(2021-12-10) Castelo Branco, Lucas Martins; Degiorgi, Sérgio Vladimir Barreiro; http://lattes.cnpq.br/7323495611053601; http://lattes.cnpq.br/1886333851347024
The diode laser, currently, has been the most used type of laser in several areas due to its low cost of operation and especially the ease in the control process and wavelength of its service. To operate it, it needs a good stabilization in its frequency, which is important not only for measurements that require high spectral resolution, but also for several research applications. For frequency stabilization of a diode laser, an automatic frequency control loop can be used. An error signal generated by the laser frequency change must be processed (amplified and filtered) and must be fed back in order to compensate for the fluctuation in frequency. The present study aims to build a circuit for frequency locking of an absolute frequency diode laser, using a synchronized detection. To lock the laser frequency, a frequency discriminator is used as a reference which will have an equally resonant transfer function. In order to be able to lock the laser frequency to the frequency of the discriminator method used, which makes it possible to generate a derivation of the transfer function of the discriminator. This method consists of simplifying a step much in the frequency of the laser to the laser light, separating it only with a small modular step, which is being broken down into at least modulation.
Análise de índices de qualidade da energia elétrica considerando uma planta de geração eólica localizada no norte da Bahia
(2022-05-27) Paiva, Jefferson; Alves, Denis Keuton; http://lattes.cnpq.br/7109075850257262; http://lattes.cnpq.br/2113363156474260
This study proposes a comparative assessment of the leading indicators of power quality measured in a wind farm located in the north of the state of Bahia. The integration of wind farms in the electric power system presents challenges related to the power quality, whose indicators must follow the standards defined as desirable. This fact highlights the importance of monitoring electrical power quality indicators, emphasizing phenomena, parameters, and reference values regarding steady-state voltage, power factor, harmonic distortion, voltage imbalance, voltage fluctuation, short duration, and frequency variation. The power quality indicators were evaluated according to the limits defined in Brazilian standards: Procedimentos de Distribuição de Energia Elétrica no Sistema Elétrico Nacional, established by the Agência Nacional de Energia Elétrica, through normative resolution No. 956/2021; Procedimentos de Rede, prepared by the Operador Nacional do Sistema Elétrico, through normative resolution No. 903/2020. The measurement of electrical quantities was performed using a PowerLogic® energy analyzer, model ION7650, manufactured by Schneider Electric, which is also responsible for measuring the plant's electricity production billing. The analysis of the quality of electric energy is carried out in the generation bus of the enterprise's substat. The recorded values of the measured electrical quantities were satisfactory for presenting a diagnosis capable of evidencing problems related to the power quality.
Procedimento para testes em sistemas de proteção de barras: arranjos barra dupla com disjuntor simples a quatro chaves
(2022-06-06) Lima, Thiago Lucas dos Santos; Araújo, Marcel Ayres de; http://lattes.cnpq.br/0669410110930611; http://lattes.cnpq.br/3741381872777674
Substation buses are of great importance for any electrical power system, as they are responsible for connecting various equipment, so a fault in the system can cause a great power outage. In this context, a testing methodology when implementing a new bar protection system can contribute significantly to ensure that the system operates satisfactorily, minimizing human error failures that can occur in the entire assembly or implementation process. of logics and giving reliability to the whole system. In this sense, this work presents a methodology for commissioning and integrating busbar protection systems for substations with double busbar arrangements with a single four-key circuit breaker. Therefore, the test steps to be carried out were described, detailing them for a better understanding of the reader and the possibility of practical application, such as the one carried out in 3 applications in energy substations. In these applications it was possible to identify failures that could cause serious problems, such as improper protection action and even non-operation when required.
Análise de qualidade de energia, gestão de modalidade tarifária e sugestão de melhorias em uma unidade rural de média tensão
(2022-09-29) Albuquerque, Eduardo Monteiro de; Macêdo, Ana Vitória de Almeida; http://lattes.cnpq.br/1157321507564630; http://lattes.cnpq.br/4268219318610805
The electrical energy has correlated countless quantities making it have the electrical power system in full working order. The operation of these systems is carried out from projects making it minimize and avoid possible accidents related to electricity. The power quality analysis and energy efficiency are crucial to understanding causes, effects and making the necessary corrections in electrical installations resulting in a longer useful life of the equipment and savings for the customer. In this work a theoretical foundation will be carried out regarding the fundamental electrical quantities to have a good quality of energy, in addition to an analysis of energy quality together with the tariff analysis in a rural medium voltage unit, through an analyzer power (P53, class B of accuracy of brand Primata Tecnologia Eletrônica), evaluating the current scenario and suggesting improvements to the installation, furthermore, a study will be carried out to adapt the consumer
Cálculo da capacidade remanescente de um sistema elétrico para escoamento de geração de energia
(2022-10-04) Agra Neto, Salviano; Macêdo, Ana Vitória de Almeida; http://lattes.cnpq.br/1157321507564630; http://lattes.cnpq.br/9906908807056658
This paper addresses the calculation of the remaining capacity of an electrical system for power generation flow, which consists of the maximum value of active power injection that the system can transmit without the occurrence of power flow violations. or tension. This topic is very relevant, especially in Brazil, where there is great energy potential and projects to expand and diversify the energy matrix. This subject is extremely important in the commercial scope of electric energy, since it is a study that precedes some energy auctions under the responsibility of the Ministry of Mines and Energy. Throughout the paper, the fundamentals to understand the problem and a computational method for its resolution are presented. The software used to perform the calculation, ANAREDE®, will also be presented, with emphasis on its automatic transmission margin calculation tool. Finally, the results from the software calculations are presented, exposed through tables containing the values of the transmission margins and their limiting factors.
Controle vetorial em quadratura de velocidade em motores de indução trifásicos para aplicações em controle de vazão de ar em ventiladores industriais
(2022-10-05) Santos, Nailson Figueiredo dos; Méllo, João Paulo Ramos Agra; http://lattes.cnpq.br/2430890141645755; http://lattes.cnpq.br/2668760030520733
Air flow control through of fans can be applied in various areas, from industry, in combustion or air renewal processes, to commercial and residential air conditioning systems. The fans responsible for airflow control are equipment whose driving force is provided by the coupling of electric induction motors on their blades, and the flow control is directly related to the motor speed control, according to the first law of fans. There are some ways to control the speed of induction motors: change in the number of poles, variation of the supply frequency, or with vector control techniques, which have good dynamic performance and efficiency. The so called vectorial techniques provide a decoupling between the magnetic flux and conjugate, enabling the independent control of these quantities, but requiring a well established dynamic model of the motor, so that it is possible to perform the tuning of the control loops. Based on this, and considering the importance of a reliable flow control, this paper aims to design a quadrature vector control system with the stator flux in closed loop, by obtaining a dynamic model of an induction motor applied to a load that simulates a fan, from an analytical methodology for obtaining the parameters of the motor model. The tests and simulations, as well as the controllers tuning were developed with PSIM and MatLab software, where results were obtained that proved the validity of the model development methodology and the controllers tuning, as well as the speed control in permanent regime foreseen.
Desenvolvimento de um protótipo de um software para um sistema não cabeado de captação de eletrocardiograma para experimentação em modelo animal
(2022-10-06) Caetano, Maria Luiza Guerra; Nogueira, Romildo de Albuquerque
Usually, cardiac activity variability research has as its methodology a study of cardiac autonomic control. In animal experiments, electrophysiological signals are obtained using chemical (drug) or mechanical (container) containment methods, which produce artifacts in the signal of interest. A solution to avoid the inconvenience produced by these procedures is the use of wireless capture systems attached to the vest. Despite the existence of equipment with this technology, the reality of research laboratories comes up against the high cost of acquiring this equipment and the relative difficulty of the size of the vests, which are produced for dogs and cats, given that they are aimed at the medical clinic. small animal veterinarian. This manuscript presents the results obtained in the development of a software prototype for a graphical interface of an unwired system for recording the electrocardiogram of Wistar rats. To analyze these results, the data obtained were compared with those captured through a wired system using commercial software. For this, the detrended fluctuation analysis (DFA) of the referred data was used, where no statistically significant differences were observed between the mean valuesobtained between the systems. Taking into account the initial results, it indicates that it is viable for improvement and future use in the experimental routine with Wistar rats, seeking to improve the quality of the data and better comfort for the experimental model.
Desenvolvimento de um supervisório em sistemas HVAC responsáveis pelo tratamento de ar em estabelecimentos assistenciais de saúde (EAS)
(2022-10-06) Silva, Maria Eduarda Albuquerque; Medeiros, Philippe Eduardo de; http://lattes.cnpq.br/5594617038786753; http://lattes.cnpq.br/2519022547136872
HVAC Systems (Heating, Ventilating and Air Conditioning) have numerous instruments to measure and control system variables. The operation of these systems is done from supervisory control and data acquisition systems that are called SCADA or Supervisory systems as they are commonly called. There are numerous softwares on the market that implement this type of supervision. However, they have a high added cost which makes them unfeasible for small systems. With this, this work aims to develop a supervisory in an open-source SCADA platform in order to enable the implementation in small projects. For this, we used a real HVAC system implemented in a hospital, a PLC (Programmable Logic Controller), data communication protocols aimed at industrial automation called BacnetIP and RS-485. This work explores the tools available on the ScadaBR platform, such as real-time monitoring of system variables, alarm generation and graphic screen development.
Sistema de powertrain de um veículo elétrico
(2022-10-06) Florentino, João Pedro de Sá; Méllo, João Paulo Ramos Agra; http://lattes.cnpq.br/2430890141645755; http://lattes.cnpq.br/9987759193674873
The automotive vehicle market is currently experiencing an advance in the development of electric vehicles, a market trend driven by the technological advancement of this sector and by a need to reduce pollution caused by automotive vehicles. In this way, it is necessary to develop a mathematical and simulation model that is capable of making predictions about the behavior of the vehicle for specific situations. In this work, a model for the powertrain system applicable to electric vehicles was developed, with mathematical models of vehicle dynamics, electric motors and magnetic flux and speed control loop. To this end, a literature review was carried out on such points. The mathematical models developed were used in simulation environments to verify the behavior of the developed control system, as well as the reaction of the powertrain system to specific situations common to the use of electric vehicles. The results show that the mathematical models developed realistically represent the dynamic behavior of electrical machines, as well as the dynamic behavior of vehicles and satisfactory responses of the control loop. Thus, it can be concluded that the models developed meet the requirements proposed at the beginning of the work.
Modelagem de baterias de chumbo-ácido para sistemas de armazenamento de energia aplicáveis junto ao sistema elétrico de potência
(2022-10-11) Lima, Yuri Chaves de; Araújo, Marcel Ayres de; http://lattes.cnpq.br/0669410110930611; http://lattes.cnpq.br/0669410110930611
Energy storage systems have different forms and configurations, which can be electrical, thermal, energy resources or natural, which require an adequate mechanism for converting this stored energy. As it encompasses an extensive area of applications, studies of energy storage technologies have gained prominence, and their use in conjunction with the electrical system has intensified by making the supply of electrical energy more reliable, serving consumers more rationally. The increasing use of battery energy storage systems has driven new research on mathematical models representing the dynamic behavior of battery charge/discharge operation, with a focus on optimizing their energy resources. This work aims at the study and implementation of a mathematical model using computational tools to simulate the behavior of a lead-acid battery in view of the increasing insertion of energy storage together with distributed generation in the electrical system. Therefore, focusing on lead-acid batteries, mathematical models were researched taking into account their computational complexity, level of representativeness of the dynamic behavior of the battery, and accuracy of results. The Jackey model was selected because its equation was based on an electrical circuit aiming at the influence of fundamental parameters such as open circuit voltage, resistance, capacitance, battery charge state, and electrolyte temperature. From these computational implementations, as a result, the characteristic curves of the lead-acid battery were obtained, whose comparison with experimental curves presented an error smaller than 1%, evidencing the effectiveness of the method developed and implemented.
Desenvolvimento de um protótipo de medidor de energia elétrica para aplicação em redes elétricas inteligentes.
(2022-10-12) Gomes, Clinton de Sousa; Araújo, Marcel Ayres de; http://lattes.cnpq.br/0669410110930611; http://lattes.cnpq.br/2029515617610539
Due to the increasing changes in the Electric Power System, new possibilities for the advancement of monitoring technologies have emerged and the concepts and methodologies brought by the smart electric grids have originated new tools and information for the concessionaires. For the implementation of an intelligent network, it is necessary to modernize the entire system, especially the measurement and monitoring techniques on the operation and operation of the network for access to more accurate and real-time data for all involved, enabling decision-making faster and thus increasing operational efficiency. In this context, the objective of this project is the study and development of a three-phase bidirectional electricity meter that makes it possible for the concessionaire to monitor, in real time, the electricity consumption of its consumer units. For this purpose, research was carried out to identify the operational characteristics and functionalities of smart meters in order to define the requirements of the system and the tools that are part of the project. To this end, the objective of this project was successfully achieved through the development of meter sensing systems using the ACS758 sensor and voltage transformers that allow the reading of electrical quantities, monitoring and communication through microcontroller ESP32, which enables the sending of data to be stored in a local database and displayed in a WEB interface. Based on the information gathered in the body of the document, a summary is made at the end of the work on the gain for the concessionaire by implementing a system such as the one proposed.
Caracterização de uma família de ressonadores planares: estruturas circulares autossimilares para aplicação de circuitos de micro-ondas
(2022-10-14) Bernardo, Helton Silva; Oliveira, Elias Marques Ferreira de; http://lattes.cnpq.br/2576044894885888; http://lattes.cnpq.br/0376996218317422
The present work aims to develop and structure a family of circular and self-similar resonator devices based on modeling by microstrip technique with planar structures to determine resonances and frequency bands, allowing to identify and locate the structuresthat resonate. The methodology behind thisstudy is described in two parts: In the computational elaboration procedure (structuring and parameterization) and the simulation in different aspects. Mathematical modeling of the family of resonator devices was carried out, the parameters of wavelength and radii of the central and adjacent resonator rings were calculated, as well as the boundary conditions for the family of resonators in a computational environment. The structures that showed adequate resonance levels were characterized by band-stop filters through the scattering parameters. The construction of the characteristic filters took place by configuring the parallel of electrical network topologies (low-pass and/or high-pass) with similar responses. The main and adjacent rings were repaired to analyze the maximum transmission and maximum resonance. This study also analyzed the surface current distributions for structures that presented different behavior in relation to their resonances. In this way, the results show: resonance in different frequency bands, tuning of parameters for maximum resonance by reparametrization and the dynamics of surface currents in the resonator rings.
Projeto e implementação de um conversor cc-cc boost com controle Proporcional-Integrativo-Derivativo (PID)
(2023-04-26) Lima, Bruno de Freitas; Oliveira, Elias Marques Ferreira de; http://lattes.cnpq.br/2576044894885888; http://lattes.cnpq.br/4293028027442685
This work proposes the analysis of PID controllers developed using a mathematical tool, pidtool, to define the controller parameters for controlling a boost converter. The boost converter is designed to ensure a 15V output with a fixed 5V input. Experiments without the use of controllers are performed to confirm the voltage level increase. When the controllers are implemented, an 8V setpoint is defined for the output to protect the connected components in case of potential failures, considering it is a prototype. Computational simulations and practical experiments are conducted using the proposed converter parameters to compare the step response of the proposed controllers. Finally, a discussion is held on the collected data, the applicability of the matlab pidtool in designing PI, PD, and PID controllers, and a brief discussion on future studies regarding the impact of different hardware types on control.