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Impact of power quality on PV performance of grid connected systemsMomoh, Ozaveshe January 2022 (has links)
The problem with the implementation of the PV generators is that majority of the UNDP offices are in developing and underdeveloped countries. Majority of these countries experience various problems with the power quality from the national electrical grid. There is also a second problem with the installed PV system, the problem is that the installed PV sources show a significant decrease in the expected annual yield ranging from 10 % – 60 % in some cases. The main aim of this thesis is to analyze the power quality in three countries (Nepal, Sao Tome and Namibia) and find the correlation between power quality and PV generation. This aim is done in five steps. The first step is the collection of measured data from the grid for a specific period of one year from July 2020 to August 2021. The collected data includes the current, voltage, power factor, frequency, reactive and active power. To achieve this, the Acuvim II power quality analyzer was sent to these three countries. In the second step, a literature review is done to research about power quality problems, identifying the power quality problems and analyzing the problems created by these identified power quality problems. In the three countries, undervoltage, overvoltage, swells, and sags where the main power quality problems which were recorded. The third step is a system case study process in which an in-depth analysis is done on the three PV systems and a simulation is done to understand the solar parameters which includes the specific yield, and performance ratio. The fourth step involves comparing the collected data from the PQ analyzer with the simulation results and determine the effects the power quality problems and system design have on the low annual yield. Also, the yearly amount of overvoltage and undervoltage in the three countries within the analysis period was analyzed. The voltage and fluctuation analysis also includes other power quality parameters which were measured. The collected parameters were analyzed and the correlation between the electrical grid requirements in the three countries were made with the recorded data. The final step involves recommending improvements and optimization techniques for the three systems to improve life cycle cost and long-term vision. Thus, analyzed results and simulated results are compared to evaluate the performance. The PV system in Namibia had the best grid conditions with all the grid parameters operating within the defined grid limits, there was a 30 % reduction in annual energy production in the Nepal system due to poor power quality conditions which included overvoltage, undervoltage, and frequency deviations. There was also a 50 % energy loss in the annual production of the PV systeminstalled in Sao Tome. Sao Tome also had the highest number of recorded outages with an average of 6 – 7 hours of outages recorded daily. Power quality problems recorded in Sao Tome included voltage fluctuation problems and frequency deviations.
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Microgrid Safety and Protection StrategiesHartono, Aryudha January 2018 (has links)
One of the challenging issues with the Microgrid is that the bidirectional power flow providedby the distributed generator (DG) which modify the fault current level. Furthermore, theinverter based-renewable energy source (IB-RES) limits the total fault current contributionto the grid due to its thermal capability. Since Microgrid should be able to operate in gridconnectedand islanded mode, protection strategies are needed to solve this challenging issue.By only having IB-RES and battery storage system, the fault condition and normaloperation cannot be distinguished. Apart from fault clearing issue, there is a consideration tostudy the fault isolation in the Microgrid under the limited fault current provided by IB-RES.To have fault isolation capability, the intelligent electrical device (IED) is needed. The firststep is to find a method that can detect a fault under the fault level modification constraint.This thesis presents a zero and negative sequence current protection to detect a fault.However, to make it selective, this protection will be applied directionally. It is common thatthe distribution grid has unbalanced load operation, thus providing zero and negativesequence component in the grid. To apply the directional zero and negative sequence currentprotection, the unbalanced load flow is simulated to distinguish the fault and normaloperation under unbalanced load condition.Safety and regulation are discussed briefly in this thesis. It is important that each of theIB-RES has fault ride-through (FRT) capability that follows a regulation. However, thisregulation is expected to have a coordination with the proposed protection in the Microgridso the reliability, selectivity, and sensitivity can be achieved in grid-connected and islandedmode. This thesis shows the coordination between fuses, IED, and inverter FRT capability.After providing a protection strategy, the adaptability of the proposed protection isassessed regarding of Microgrid expansion. The result shows that by applying the schemeand following the grading margin requirement that is presented in this thesis, the Microgridexpansion will not disrupt the proposed protection coordination. Since it is known that thedistribution grid is expanding its load capacity and microgeneration in continuous basis, it isconvenient that the proposed protection in the IED is expected to be adaptable, means that ithas a fixed IED setting when the grid is expanded. The analysis is performed by electrical transient analysis program (ETAP) and MatlabSimulink. The short circuit analysis, sequence-of-operation, and unbalanced load flow aresimulated by ETAP, while the protection stability is simulated by Matlab Simulink. / Ett problem som finns med microgrid är att de distribuerade produktionsgeneratorerna harett dubbelriktat effektflöde som modifierar felströmmen. Dessutom, inverterbaseradeförnyelsebara energikällor (IB-RES) begränsar det totala felströmsbidraget på grund av desstermiska kapacitet. Eftersom microgrids ska vara operativ vid både anslutning till externt nätsamt önätsdrift behövs skyddsstrategier för att kunna hantera fel, speciellt vid önätsdrift.Om endast IB-RES och batterilager används kan feldrift och normal drift inte särskiljas.Bortsätt från felhantering är det viktigt att studera felbortkoppling för microgrid underbegränsad felström som fås av IB-RES. För att kunna åstadkomma felbortkoppling behöveren IED (från engelskans Intelligent Electronic Device). Det första steget är att finna en metodför att kunna detektera fel under fel nivå modifiering. Denna avhandling tittar på att användanoll- och minusföljds ström sekvensskydd för att detektera fel. För att göra skyddet selektivtkommer det att titta på riktningen av effektflödet. I distributionsnät är det vanligt att haobalanserade laster vilket medför noll- och negativa sekvenskomponenter i nätet. För atttillämpa riktningsskydd för noll och negativ sekvens ström simuleras ett obalanserateffektflöde för att särskilja på feldrift och normal drift vid obalanserad last.Säkerhet och förordningar diskuteras kortfattat i denna avhandling. Det är viktigt att varjeIB-RES har en feltålighet som följer vissa förordningar. Denna förordning förväntassamordna det föreslagna skyddet i micronåt så att pålitlighet, selektivitet och känslighet kanåstadkommas vid nätanslutning och önätsdrift. Denna avhandling visar samordningen mellansäkringar, IED och feltåligheten för växelomriktare.Anpassningsförmågan för det föreslagna skyddet bedöms med avseende på expansion avmicrogrid. Resultatet visar att en expansion av ett microgrid inte kommer att störa denföreslagna samordningen om skyddsmetoden och tidsfördröjningskravet som presenteras idenna avhandling följs. Eftersom det är känt att distributionsnätet kommer att fortsätta ökasin lastkapacitet och mikrogenerering, är det lämpligt att skyddet förväntas varaanpassningsbart vilket innebär att det har en fast IED inställning när nätet expanderas.Analysen genomförs med mjukvarorna electrical transient analysis program (ETAP) ochMatlab Simulink. Kortslutningsanalysen, arbetssekvensen och obalanserad lastflödesimuleras av ETAP, medan skyddsstabiliteten simuleras av Matlab Simulink.
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Energy Provisioning in Stand-alone and Grid-Connected Solar Powered NetworksSheikh, Zefreh Mohammad 04 1900 (has links)
<p>Solar energy is a clean and abundant renewable energy source which is currently used in many types of photovoltaic (PV) designs. In practical PV systems, solar panels are used to harvest solar energy and convert it into a usable form of electricity. Due to the intermittent nature of solar energy input however, battery storage, in combination with solar panels, must be used to provide an uninterrupted source of power.</p> <p>The process of assigning solar panel and battery configurations for a PV system is referred to as energy resource provisioning. Unfortunately, energy provisioning costs are still relatively high, and this is one of the main obstacles that inhibits the adoption of solar power for many applications. These costs however, can be substantially reduced through cost-efficient resource provisioning methods. The focus of this thesis is on the development of efficient algorithms and energy management methods that will reduce energy provisioning costs in solar powered systems.</p> <p>First, we consider resource provisioning in solar powered wireless mesh networks. In practical solar powered systems, there are usually restrictions in the way that the mesh nodes can be positioned, and this results in a time-varying and node-dependent attenuation of the available solar energy. Unfortunately, conventional resource provisioning methods cannot take this into account and therefore the deployed system may be unnecessarily expensive. In this part of the thesis, the resource provisioning problem is considered from this point of view. We first review conventional resource provisioning mechanisms and give an example which shows the value of introducing positional solar insolation awareness. A Position Aware Provisioning (PAP) algorithm is then introduced that takes known positional variations into consideration when performing the energy provisioning. Simulation results show that reductions in total network provisioning cost can be obtained using the proposed methodology compared to conventional algorithms.</p> <p>In the second part of the thesis, we consider communication infrastructure that is operated from the power grid with a solar powered addition. Resource provisioning and energy management algorithms are introduced to minimize the capital expenditure (CAPEX) and operating expenditure (OPEX) costs. We first derive lower bounds on the costs using a linear programming (LP) formulation where solar components are sized using solar insolation and projected loading data. A variety of different node configurations are considered. Three energy scheduling algorithms are then introduced to optimize online OPEX costs, namely, Grid Purchase Last (GPL), Solar Load Optimization (SLO) and Solar Load Simulation (SLS) algorithms. Simulation results show the extent to which a solar powered add-on can reduce total cost.</p> <p>Finally, we consider solar powered systems where part of their energy demands are deferrable, up to some maximum tolerable delay. The objective is to exploit the flexibility of deferrable energy demands in a way that decreases the total provisioning cost. A mixed integer linear optimization program is derived which gives a lower bound on the provisioning cost. A Delay Aware Provisioning (DAP) algorithm is then proposed to determine practical cost-efficient energy provisioning. The performance of DAP is compared to the provisioning bound and the conventional Stand-alone Node Provisioning (SNP) algorithm. Results are presented which show the significant provisioning cost savings that can be obtained.</p> / Doctor of Philosophy (PhD)
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Resonant Boost Converter for Distributed Maximum Power Point Tracking in Grid-connected Photovoltaic SystemsSimeonov, Gregor 03 December 2012 (has links)
This thesis introduces a new photovoltaic (PV) system architecture employing low voltage parallel-connected PV panels interfaced to a high voltage regulated DC bus of a three-phase grid-tied inverter. The concept provides several improvements over existing technologies in terms of cost, safety, reliability, and modularity. A novel resonant mode DC-DC boost converter topology is proposed to enable the PV modules to deliver power to the fixed DC bus. The topology offers high step-up capabilities and a nearly constant efficiency over a wide operating range. A reduced sensor maximum power point tracking (MPPT) controller is developed for the converter to maximize energy harvesting of the PV panels. The reduced sensor algorithm can be generally applied to the class of converters employing pulse frequency modulation control. A ZigBee wireless communication system is implemented to provide advanced control, monitoring and protection features. A testbench for a low cost 500 $W$ smart microconverter is designed and implemented, demonstrating the viability of the system architecture.
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Resonant Boost Converter for Distributed Maximum Power Point Tracking in Grid-connected Photovoltaic SystemsSimeonov, Gregor 03 December 2012 (has links)
This thesis introduces a new photovoltaic (PV) system architecture employing low voltage parallel-connected PV panels interfaced to a high voltage regulated DC bus of a three-phase grid-tied inverter. The concept provides several improvements over existing technologies in terms of cost, safety, reliability, and modularity. A novel resonant mode DC-DC boost converter topology is proposed to enable the PV modules to deliver power to the fixed DC bus. The topology offers high step-up capabilities and a nearly constant efficiency over a wide operating range. A reduced sensor maximum power point tracking (MPPT) controller is developed for the converter to maximize energy harvesting of the PV panels. The reduced sensor algorithm can be generally applied to the class of converters employing pulse frequency modulation control. A ZigBee wireless communication system is implemented to provide advanced control, monitoring and protection features. A testbench for a low cost 500 $W$ smart microconverter is designed and implemented, demonstrating the viability of the system architecture.
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Otimização meta heurística e controle baseado no modelo interno aplicados em sistemas de geração fotovoltaica conectados à rede elétrica monofásicaChaves, Eric Nery 18 November 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho apresenta o estudo, desenvolvimento e aplicação de novas técnicas de controle aos
sistemas de geração de energia fotovoltaica, conectados à rede elétrica monofásica, visando a
melhoria da eficiência destes sistemas em relação aos métodos de controle tipicamente utilizados. O
trabalho é dividido em duas partes principais, as quais estão relacionadas ao rastreamento do ponto
de máxima potência (Maximum Power Point Tracking – MPPT) e, depois, ao controlador interno
dos conversores boost-quadrático – lado dos painéis fotovoltaicos – assim como aos controladores
do inversor de tensão, no lado da rede elétrica monofásica. A primeira parte do trabalho consiste no
desenvolvimento de um algoritmo de meta heurística para o MPPT, o qual é baseado no método do
recozimento simulado (Simulated Annealing - SA) e tem como objetivo a determinação do ponto de
máximo global, buscando soluções fora de uma vizinhança próxima, de modo a evitar o
atracamento em máximos locais da curva de potência de saída do arranjo de painéis fotovoltaicos,
melhorando, assim, o aproveitamento da energia em situações de sombreamento parcial. A segunda
parte do trabalho apresenta o projeto de controladores baseados no modelo interno (Internal Model
Control – IMC) com 1 grau de liberdade (1 Degree of Freedom – 1 DOF) aplicados, primeiramente,
ao conversor CC-CC Boost Quadrático, utilizado para o MPPT, e, posteriormente, a um inversor de
tensão com filtro LCL, conectado à rede elétrica monofásica, operando no modo de injeção de
corrente. É apresentada a modelagem matemática de ambos os conversores e analisada a
compensação da realimentação interna ao sistema do inversor de tensão, correspondente ao
desacoplamento da tensão da rede, através da estratégia de alimentação à frente (Feedforward).
Visando-se uma base de comparação, para a análise de desempenho do conversor IMC – 1DOF,
também é aplicado ao sistema de injeção de corrente, o controlador Proporcional-Ressonante
(P+Res). São apresentados resultados de simulação computacional e experimentais de ambos os
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controladores, os quais permitem verificar o desempenho do sistema em situação de rede fraca e
carga local não-linear. / This paper presents the study, development and application of new control techniques for
photovoltaic power generation systems, connected to single-phase power grid in order to improve
the efficiency of these systems in relation to control methods typically used. The work is divided
into two main parts, which are related to tracking the maximum power point (Maximum Power
Point Tracking - MPPT) and then the internal controller of boost quadratic converters - side of the
photovoltaic panels - as well as the controllers the voltage inverter, the side of the single-phase
mains. The first part of the work is the development of a heuristic goal algorithm for MPPT, which
is based on the method of simulated annealing (Simulated Annealing - SA) and aims at determining
the overall maximum point, seeking out solutions in a close vicinity, so as to prevent the docking
local maxima in the curve of power output of the photovoltaic array, thereby improving the
utilization of energy in partial shading situations. The second part presents the design of controllers
based on internal model (Internal Model Control - IMC) with 1 degree of freedom (1 Degree of
Freedom - 1 DOF) applied, first, the DC-DC Boost Quadratic converter, used for MPPT, and
thereafter, a voltage inverter with LCL filter connected to the single phase power supply operating
in current injection mode. A mathematical modeling of both converters and analyzed the
compensation of internal feedback to the voltage inverter system corresponding to the disconnection
of the mains voltage through the power strategy a head (feedforward). A basis of comparison for the
performance analysis of IMC-1DOF converter is aiming at, is also applied to the current injection
system, Proportional-Resonant Controller (P + Res). They are presented computer simulation and
experimental results of both controllers, which allow you to check the system performance in low
and non-linear local load network situation. / Tese (Doutorado)
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Sistema de geração distribuída fotovoltaica com acumulação, controle da injeção de potências ativa e reativa, com capacidade de operação conectada e ilhada /Alves, Marcos Gutierrez. January 2017 (has links)
Orientador: Carlos Alberto Canesin / Resumo: Frente aos novos desafios impostos ao cenário energético mundial, esta tese de doutorado implementa e analisa uma micro-rede de geração distribuída (GD), com acumulação e capacidade de operação conectada ou desconectada da rede de distribuição de energia elétrica (RDEE). A energia é fornecida à RDEE através de seis inversores monofásicos, constituindo uma rede trifásica, sendo três deles com capacidade de operação ilhada e conectada, e outros três com características de fonte de corrente que podem injetar energia de forma controlada, ativa ou reativa, no ponto de conexão comum (PCC). Através do sistema de acumulação com baterias do tipo chumbo-ácido, também é possível que o sistema minimize o consumo de energia da RDEE, mesmo quando não há energia solar, extraindo potência das baterias. Tendo em vista que a quase totalidade dos inversores utilizados em um sistema de GD fornecem somente potência ativa, ou trabalhem com fator de potência fixo, este trabalho também implementa o controle dinâmico de P e Q na micro-rede, atuando como compensador de tensão no PCC e promovendo melhorias na qualidade da energia elétrica. A micro-rede é gerenciada por um programa desenvolvido para o controle de todos os dispositivos essenciais presentes na GD, incluindo controle da carga e descarga do sistema de acumulação, controle dos contatores de conexão de todo o sistema, e controle do firmware dos inversores conectados, permitindo total liberdade de gestão da energia disponível, resultando numa ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Considering the new challenges imposed in the energetic scenario around the world, this PhD thesis implements and analyzes a micro-grid of Distributed Generation (DG) plant with accumulation and capability of operation connected or islanded from the electric power distribution grid. The system will supply power to the utility grid and local loads through six single-phase inverters, constituting a three-phase system, among which three are with capability to operate in islanded and connected mode, and the other three single-phase inverters with current source characteristic that can inject active or reactive power in a controlled manner at the point of common coupling (PCC). Through the accumulation system with lead-acid batteries technology, it is also possible that the system minimizes the utility grid consumption, though without solar energy. Given that most of the available inverters for DG are designed only to provide active power or to operate with a fixed power factor, this work, in the meantime, implements the dynamic control of the supplied active and reactive power (P and Q) in micro-grid, acting as a voltage compensator at the PCC to improve the quality of electric power. The micro-grid is managed by software designed to control and communicate with all essential devices in DG, including control of charge and discharge of the accumulation system, control of the whole system connection contactors, and the firmware control of grid connected inverters, which allow a wid... (Complete abstract click electronic access below) / Doutor
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Inversores fotovoltaicos conectados à rede com armazenamento de energia – classificação, recomendações técnicas e gerenciamento / Grid-connected photovoltaic energy storage systems – classification, technical recommendations and managementBellinaso, Lucas Vizzotto 08 March 2017 (has links)
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Grid-connected photovoltaic systems with energy storage have features of conventional gridconnected
inverters and uninterruptible power supplies. In these systems, all elements, which
include photovoltaic generator, batteries, loads and electric grid, are connected to the same
equipment named multifunctional photovoltaic converter. As it is a recent technology, there
are many research opportunities in this theme, from classifications and standards to specific
problems. This study investigates this field in a comprehensive manner, proposing
classifications, technical recommendations and a power management strategy. Initially,
classifications are proposed considering system configuration and continuity of supply to the
loads. In the following, technical recommendations related to grid and load compatibility, as
well as safety technical recommendations, are proposed. The last proposal consists on a power
management strategy which defines the operation mode of the static converters and system
elements as a function of the energy scarcity. Experimental results of the power management
are presented in order to validate the proposals. In this way, this thesis contributes to the
development of multifunctional photovoltaic converters technology so that the distributed
generation becomes more independent of solar availability and can better collaborate with the
electric system. / Sistemas fotovoltaicos conectados à rede com armazenamento de energia são aqueles que
conjugam características dos inversores conectados à rede convencionais e de fontes
ininterruptas de energia. Nesses sistemas, todos os seus elementos, que incluem o gerador
fotovoltaico, as baterias, as cargas e a rede elétrica, são conectados a um mesmo equipamento
chamado de conversor fotovoltaico multifuncional. Por se tratar de uma tecnologia recente,
existem muitas oportunidades de pesquisa inédita no tema, desde premissas e classificações
básicas até a solução de problemas mais específicos. Este trabalho investiga o tema de
maneira abrangente, propondo classificações, recomendações técnicas e uma estratégia para
gerenciamento interno de potência dos conversores fotovoltaicos multifuncionais.
Inicialmente, classificações são propostas considerando a configuração do sistema e a
continuidade de fornecimento de energia às cargas. A seguir, são propostas recomendações
técnicas relacionadas à compatibilidade com a rede e com as cargas, além de recomendações
técnicas de segurança, baseando-se em normas existentes. A última proposta consiste em uma
estratégia de gerenciamento interno de potência que define os modos de operação dos
conversores estáticos e dos elementos do sistema em função da escassez de energia.
Resultados experimentais do método proposto para o gerenciamento interno de potências são
apresentados com o objetivo de validar as propostas desenvolvidas. Dessa forma, o presente
trabalho contribui com o desenvolvimento da tecnologia de conversores fotovoltaicos
multifuncionais, para que a geração distribuída de energia elétrica se torne mais independente
da disponibilidade solar e possa melhor colaborar com o sistema elétrico.
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Modeling and Analysis of Grid Connected Variable Speed Wind GeneratorsSeshadri Sravan Kumar, V January 2015 (has links) (PDF)
The growing demand for power and increased environmental concerns gave an impetus to the growth of clean and renewable energy sources like wind, solar etc. There is a remarkable increase in the penetration of wind energy systems in the last decade and this trend is bound to increase at a much faster pace in future. This ever increasing penetration of wind power generating systems pose multi-fold challenges related to operational and stability aspects of the grid. Present day wind energy systems mostly comprise of variable speed wind generators. A large fraction of present day variable speed wind turbine generators use doubly fed induction machine (DFIM).
This thesis deals with modeling and grid coordination aspects of variable speed wind gener- ators. In particular, the short coming of the existing steady state equivalent circuit of a DFIM is identified and subsequently, an accurate equivalent circuit of a DFIM is proposed. Relevant mathematical basis for the proposed model is presented. The proposed steady state equivalent circuit of a doubly fed induction machine is further validated using dynamic simulations of a standalone machine.
Based on the proposed equivalent circuit, two approaches for computing the initial values of state variables of a DFIM is proposed. The first approach is a linear formulation where the losses due to resistance of the stator and rotor windings are neglected. The second approach is a non-linear formulation which takes the losses into consideration.
Further, analysis is carried out on grid connected doubly fed induction generators (DFIG). A framework to incorporate DFIG based variable speed wind farms in the steady state power flow analysis is proposed. The proposed framework takes into consideration important aspects such as voltage dependent reactive power limits and mode of reactive power control of associated converters. Some of the challenges in a grid connected DFIG especially during su- persynchronous mode of operation are identified. The advantages of a non-Maximum Power Point Tracking (MPPT) mode of operation under certain operating conditions is highlighted.
Finally, aspects pertaining to coordination of grid connected variable speed wind generators are studied. A trust region framework to determine the reference values to the control loops of converters in a variable speed wind generator is proposed. The proposed framework identifies the reference values considering other reactive power controllers in the grid. Moreover, the proposed framework ensures that the steady state voltage stability margin is maximized. On the computational front, trust region algorithms ensure global convergence.
The mathematical models and initialization algorithms proposed in this thesis are tested on standalone systems under various control scenarios. The algorithms proposed to incorporate a grid connected DFIG in steady state analysis tools have been tested on a sample 6-bus system and a practical 418-bus equivalent system of Indian southern grid.
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Análise de impactos de um sistema fotovoltaico conectado à rede em Mossoró/RN / Analysis of the Impacts of grid-connected photovoltaic system in Mossoró/RNBalbino, Isaú Macêdo 29 August 2017 (has links)
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Previous issue date: 2017-08-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Environmental problems, like global warming and pollution, together with the rising fossil fuels prices in recent years have increased search for alternative energy sources, that are clean and sustainable at the same time. Among the main sources, it is possible to highlight the photovoltaic solar energy. For being a source of clean renewable energy with a low maintenance rate, photovoltaic solar energy has been gaining attention worldwide, and with this the Grid-Connected Photovoltaic System (GCPV) has grown in the last decades. Despite the benefits from the GCPV, for being a relatively new technology when compared with other energy sources, the same is not yet fully consolidated, and its installation requires care in regard to quality of electrical power. Problems such as production of harmonics, overvoltage and low power factor are common to these types of systems. Several researches are conducted every year and regulations are created, in order to reconcile the photovoltaic generation with the power distribution network. Therefore, the present work aims to identify, measure and analyze the behavior of GCPV of 3 kWp of UFERSA, in the city of Mossoró-RN, in order to verify the possible impacts to the quality of the electric energy associated with GCPV. In this research it was noticed that all the parameters are within the current standard regulations, however the high indexes of harmonic distortion rate made necessary the elaboration of a low-pass filter to attenuate the unwanted frequencies. With the simulation of the filter in Simulink, an attenuation of up to more than 60% was verified, thus improving the quality of the energy generated by the system / Os problemas ambientais, como o aquecimento global e a poluição, juntamente com o crescente preço dos combustíveis fósseis nos últimos anos, elevaram a procura por fontes alternativas de energia, que ao mesmo tempo fossem limpas e sustentáveis. Dentre as principais fontes, pode-se destacar a energia solar fotovoltaica. Por ser uma fonte de energia limpa, renovável e com baixo índice de manutenção, a energia solar fotovoltaica vem ganhando destaque no mundo inteiro, e com isso os Sistemas Fotovoltaicos Conectados à Rede (SFCR) cresceu nas últimas décadas. Apesar dos benefícios oriundos dos SFCR, por ser uma tecnologia relativamente nova quando comparada com outras fontes de energia, a mesma ainda não está totalmente consolidada, e sua instalação requer cuidados no que diz respeito à qualidade de energia elétrica. Problemas como produção de harmônicos, sobretensão e baixo fator de potência são comuns a estes tipos de sistemas. Várias pesquisas são realizadas todos os anos, e normas e regulamentos são criados, a fim de conciliar a geração fotovoltaica com a rede elétrica de distribuição. Portanto, o presente trabalho tem como objetivo identificar, medir e analisar o comportamento do SFCR de 3 kWp da UFERSA, na cidade de Mossoró-RN, a fim de se verificar os possíveis impactos à qualidade da energia elétrica associados aos SFCR’s. Nesta pesquisa percebeu-se que todos os parâmetros estão dentro das normas vigentes, porém os altos índices de taxa de distorção harmônica fizeram necessário a elaboração de um filtro passa-baixa para atenuar as frequências indesejadas. Com a simulação do filtro no Simulink, constatou-se uma atenuação de até mais de 60%, melhorando assim a qualidade da energia gerada pelo sistema / 2018-01-17
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