Automated fault location systems use power quality monitoring and circuit data to provide with a distance or impedance estimate to the fault. This can be used to avoid manual patrolling of the entire feeder in case of a main feeder lockout. It can also be used for circuits with repeated momentary interruptions to pinpoint the section of the circuit causing such problems. Self clearing sub cycle faults have been identified as the precursors of a number of sustained faults (requiring the operation of protective device) in utility distribution networks. The frequency of such incipient faults increases considerably as they are about to evolve into a full blown fault. This report proposes a modified and improved fault location algorithm that can be used to accurately identify sustained as well as temporary faults. The algorithm is based in the time domain and takes into account the arc voltage during a fault event. The proposed algorithm is developed, validated and applied to known distribution field data. Time domain simulation models are also used for validation purposes. The developed algorithm was observed to be very accurate when compared to other impedance based fault location algorithms proposed in the literature. Finally, sub cycle event identification and fault pre-location is proposed that can be very useful for electric utility operations. Highly accurate results were observed during this application study. For instance, a current waveform containing three incipient and one full fault event is shown in the figure given below. The estimated reactance to an incipient fault location is approximately 1.1 Ω. The fault location results obtained from the first three sub-cycle faults can be used to avert the final sustained fault event. / text

Orientador: Fujio Sato / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-21T20:17:53Z (GMT). No. of bitstreams: 1 Oliveira_Wagnerde_M.pdf: 29762769 bytes, checksum: a8dc59d5c389eb687d639b8519c57213 (MD5) Previous issue date: 2012 / Resumo: Neste trabalho, intitulado "Simulação para a Avaliação do Desempenho do Sistema de Proteção de Distância de uma Linha de Transmissão de 500 kV", são descritos os princípios básicos das proteções dos sistemas de potência, a evolução dos equipamentos e dos procedimentos de ensaios, simulações em tempo real, análise de desempenho de um sistema de proteção de linha de transmissão e simulações no modelo computacional. Nos Capítulo 1 e 2 são destacados alguns aspectos importantes do sistema de potência, seguido de noções de proteção de linhas de transmissão, realçando os relés de distância e o esquema de teleproteção. No Capítulo 3 são descritos a evolução dos equipamentos e procedimentos para os ensaios, concomitante aos avanços tecnológicos dos relés de proteção, desde os relés eletromecânicos até os relés numéricos. No Capítulo 4 são descrito as simulações em tempo real e as análises dos resultados. Estas simulações foram executadas na LT 500 kV Tucuruí-Vila do Conde que integra o Sistema Norte-Nordeste da ELETRONORTE e EATE, utilizando o RTDS. As saídas em forma de sinais analógicos (tensões e correntes) e digitais (eventos) possibilitaram as análises de desempenhos dos relés, do sistema de teleproteção e disjuntores. E no Capítulo 5 temos a parte final da dissertação, demonstrando o desenvolvimento de um modelo computacional para simular as trajetórias das impedâncias de faltas de forma a confrontá-las com as características quadrilaterais de impedância do relé de distância REL 531 no plano R-X utilizado durante a simulação no RTDS, o que permitiu a análise dos ajustes das zonas de proteção / Abstract: This work, entitled "Simulation for Performance Evaluation System of Distance Protection of a Transmission Line 500 kV," describes the basic principles of protection of power systems, the evolution of equipment's and testing procedures, real-time simulations performance analysis of a system of protection of transmission line and the computer model simulations. In Chapter 1 and 2 are highlights some important aspects of the power system, followed by notions of protection of transmission lines, enhancing distance relays and pilot relaying scheme. In Chapter 3 describes the evolution of equipment and procedures for testing, concomitant technological advances of protective relays from electromechanical relays by numerical relays Described in Chapter 4 are the real-time simulations and analyzes of the results. These simulations were performed at 500 kV Tucuruí-Vila do Conde system which integrates the North and Northeast ELETRONORTE and EATE using the RTDS. The outputs in the form of analog signals (voltages and currents) and digital signals (events) enabled the analysis of performances of relays, pilot relaying scheme (teleprotection system) and circuit breakers. In the Chapter 5, we have the final part of the dissertation, demonstrating the development of a computational model to simulate the trajectories of impedances faults in order to compare them with the quadrilateral characteristics parameters of the distance protection zones REL 531 line protection plane used during R-X RTDS simulation, which allowed the analysis of the protection zone adjustments / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

<p>U disertaciji je predložen algoritam za proračun kratkih spojeva zasnovan na korelisanim intervalima. U savremenim distributivnim mrežama postoje različiti tipovi generatora koji proizvode električnu energiju iz energije obnovljivih izvora. Za takve generatore, kao i za potrošače, karakteristično je to što je njihova proizvodnja i potrošnja neizvesna. Predloženi algoritam u disertaciji uvažava te neizvesnosti, kao i korelacije između navedenih elemenata. Neizvesnosti su modelovane intervalima i direktno su uvažene u predloženom algoritmu za proračun kratkih spojeva. Algoritam je prvenstveno razvijen za proračun kratkih spojeva savremenih distributivnih mreža sa velikim brojem distribuiranih generatora i potrošača. NJime je moguće proračunavati režime sa kratkim spojevima distributivnih mreža velikih dimenzija, što je numerički verifikovano u disertaciji. Predloženim algoritmom se dobija režim distributivne mreže sa kratkim spojem koji je realističniji od režima dobijenih algoritmima sa determinističkim pristupom. Proračuni kao što su: koordinacija, podešenje i provera osetljivosti relejne zaštite, provera kapaciteta prekidača i osigurača, lokacija kvara itd. mogu na osnovu realističnijeg režima, dobijenog predloženim algoritmom, da daju kvalitetnije rezultate, što je numerički potvrđeno na primeru koordinacije prekostrujne zaštite</p> / <p>In this dissertation an algorithm for correlated intervals-based short-circuit calculation is<br />proposed. In modern distribution networks there are various types of generators that produce<br />electric energy from renewable energy resources. For these generators, as well as loads, uncertain<br />production and consumption is characteristic. The proposed algorithm in the dissertation deals<br />with above-mentioned uncertainties, as well as correlations among them. The uncertainties are<br />modeled with intervals and directly taken into account in the proposed algorithm for short-circuit<br />calculation. The algorithm is primarily developed for short-circuit calculation in modern<br />distribution networks with a great number of distributed generators and consumers. The proposed<br />algorithm enables calculation of short circuits states of large-scale distribution networks, which is<br />numerically verified in the dissertation. The proposed algorithm provides short circuit state of<br />distribution network which is more realistic than the one obtained with algorithms with<br />deterministic approach. Calculations such as: coordination, settings and sensitivity check of relay<br />protection, breaker and fuse capacity check, fault location, etc. can give better results, on the basis<br />of the more realistic state obtained by the proposed algorithm for short circuit calculation, which<br />is numerically confirmed by the example of coordination of overcurrent protection.</p>

Organic solar cells have shown great promise of becoming a cheaper alternative to inorganic solar cells. Additionally, they can also be made semitransparent. To avoid using expensive indium tin oxide electrodes in organic solar cells the electrodes can be made from conductive polymer, poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). However, these so-called PEDOT-PEDOT solar cells are prone to short-circuiting. The work behind this thesis thus aimed to find the cause of these short circuits. The initial working hypothesis assumed the hygroscopic PSS in the bottom electrode could attract water across the active layer when the top electrode layer was applied. This would then swell the bottom electrode and cause the active layer to crack leading to short circuits. Accordingly, swelling was investigated as it was suspected to be the main cause of the shorts. This was achieved by coating reflective substrates with different layers from the solar cell, dropping water on top of the stack and then filming the thin film interference effects. SEM, AFM and IR were also used for further analysis. Although the bottom electrode swells, it was found that water does not cause permanent cracking. Instead, the research unveiled that water causes a formation of blisters, which are suspected to be made of PSS. The exact mechanism for the formation of the shorts remains unclear however.

Estudos mostram que vivemos uma crise socioambiental sem precedentes. Apesar de ser considerada uma crise sistêmica, a agricultura convencional progride, constituindo uma das atividades que mais contribui para os impactos negativos tanto ambientais como sociais da atualidade. No mundo, as relações socioeconômicas estão estabelecidas segundo uma ordem de valores, na qual justificações mercantis e industriais possuem uma grande aceitação e legitimidade. A economia é considerada, para alguns autores, como o coração das ações humanas. No entanto, tal ordenamento fundado em justiça industrial-mercantil impacta negativamente diversas dimensões da vida em sociedade. Neste quadro, movimentos de contestação desta ordem emergem buscando legitimidade com vistas à profundas transformações sociais e ambientais. É assim que ocorre a multiplicação das CSAs (Comunidade que Sustenta a Agricultura), representando uma experiência inovadora de associativismo, aproximando consumidores e agricultores. Seu crescimento é exponencial no Brasil e no mundo. Trata-se de uma perspectiva de busca de uma nova estrutura de relação socioeconômica com a agricultura familiar, pautadas em princípios de um compromisso com a agroecologia, a solidariedade, a confiança mútua e a localidade. Nosso estudo aspira traçar seus potenciais e limitações em termos de aceitação social com o apoio de análises inspiradas na teoria das justificações, considerando a emergência de uma nova ordem de justiça, a justiça ecológica. / Studies show that we are experiencing an unprecedented socio-environmental crisis. Despite considered a systemic crisis, conventional agriculture is progressing, constituting one of the activities that contributes most to the negative environmental and social impacts in present time. In the world, socioeconomic relations are established according to an order of values, in which market and industrial justifications have great acceptance and legitimacy. The economy is considered, for some authors, as the heart of human actions. However, such an order based on industrial-mercantile justice impacts negatively various dimensions of life in society. In this context, movements contesting this order emerge seeking legitimacy towards profound social and environmental transformations. This is how CSAs (Community Supported Agriculture) multiply, representing an innovative experience of associativism, bringing together consumers and farmers. Its growth is exponential in Brazil and in the world. It seeks a new socioeconomic relationship structure, based on a commitment to an agroecological agriculture, solidarity, mutual trust and locality. Our study aspires to trace its potentials and limitations in terms of social acceptance with the support of analyzes inspired by the theory of justifications, considering the emergence of a new order of justice, the ecological justice.

Protection of both the wind plant and the interconnecting transmission system during short-circuit faults is imperative for maintaining system structural integrity and reliability. The circuit breakers and protective relays used to protect the power system during such events are designed based upon calculations of the current that will flow in the circuit during the fault. Sequence-network models of various power-system components, such as synchronous generators, transformers, transmission lines, etc., are often used to perform these calculations. However, there are no such models widely accepted for certain types of wind-turbine generators used in modern wind plants. The problem with developing sequence-network models of wind plants is that several different wind-turbine generator designs exist; yet, each exhibit very different short-circuit behavior. Therefore, a “one size fits all” approach is not appropriate for modeling wind plants, as has been the case for conventional power plants based on synchronous-generator technology. Further, many of the newer wind-turbine designs contain proprietary controls that affect the short-circuit behavior, and wind-turbine manufacturers are often not willing to disclose these controls. Thus, protection engineers do not have a standard or other well-established model for calculating short-circuit currents in power systems with wind plants. Therefore, the research described in this dissertation involves the development of such models for calculating short-circuit currents from wind-turbine generators. The focus of this dissertation is on the four existing wind-turbine generator designs (identified as Types 1 – 4). Only AC-transmission-interconnected wind-turbine generators are considered in this dissertation. The primary objective of this research is the development of sequence-network models, which are frequency-domain analysis tools, for each wind-turbine generator design. The time-domain behavior of each wind-turbine generator is thoroughly analyzed through transient simulations, experimental tests on scaled wind-turbine generator test beds, and solutions to the system dynamic equations. These time-domain analyses are used to support the development of the sequence-network models.

Submitted by Débora Pavani Silva (depavanisilva@gmail.com) on 2018-11-13T18:53:31Z No. of bitstreams: 1 Débora Pavani Silva - dissertação versão final.pdf: 3197592 bytes, checksum: 6cba09873c8e0010fdf9a31310be23c8 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-11-14T16:07:22Z (GMT) No. of bitstreams: 1 silva_dp_me_ilha.pdf: 3197592 bytes, checksum: 6cba09873c8e0010fdf9a31310be23c8 (MD5) / Made available in DSpace on 2018-11-14T16:07:22Z (GMT). No. of bitstreams: 1 silva_dp_me_ilha.pdf: 3197592 bytes, checksum: 6cba09873c8e0010fdf9a31310be23c8 (MD5) Previous issue date: 2018-09-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Com a modernização da agricultura nas décadas de 1960 e 1970, houve uma substituição das sementes tradicionais cultivadas por sementes comerciais geneticamente melhoradas, geralmente associadas a pacotes tecnológicos que incluíam mecanização, fertilizantes sintéticos e agrotóxicos. As sementes crioulas permitem que o agricultor mantenha sua alimentação mesmo em épocas de adversidade climática, pois são adaptadas aos ecossistemas nos quais ocorre o cultivo e ampliam sua autonomia produtiva por serem menos exigentes em relação aos insumos externos. O Território Prof. Cory/Andradina (SP), apesar da sua característica histórica de alta concentração fundiária, apresentou avanços em termos de desconcentração com a criação de quase quarenta assentamentos. O objetivo deste estudo foi realizar um diagnóstico da produção de sementes crioulas, identificar os guardiões de sementes nos assentamentos rurais do Território Prof. Cory/Andradina (SP). Foram pesquisados os aspectos socioeconômicos dos guardiões, as variedades locais e tradicionais conservadas por eles, as práticas agrícolas utilizadas, destino da produção oriunda das sementes crioulas, métodos de obtenção e troca e a atuação de instituições públicas na conservação desses materiais. Foram visitados 28 assentamentos do Território, no período entre setembro de 2017 até junho de 2018. A primeira etapa constou da identificação alguns agricultores guardiões de sementes já conhecidos por meio de informantes chaves (técnicos da extensão rural e pesquisadores que atuam na área) para que a partir desses guardiões, pelo método “bola de neve”, fossem identificados outros guardiões. A coleta dos dados se deu por meio de registros fotográficos e de um questionário semiaberto (perguntas fechadas e abertas), aplicado na forma de entrevista junto aos produtores guardiões identificados. Para uma análise da atuação das instituições públicas na conservação da agrobiodiversidade, foram entrevistados três profissionais de entidades atuantes no Território. Constatou-se que o Território Prof. Cory/Andradina não apresenta uma forte tradição em relação à conservação de sementes crioulas, porém algumas famílias mantém o costume de ter sua própria semente, especialmente para cultivos visando o autoconsumo. Foram identificados 55 guardiões em 24 assentamentos rurais, sendo o feijão catador a semente mais frequentemente encontrada. O destino amplamente predominante da comercialização são os circuitos curtos, em que se destacam a venda avulsa ao consumidor e em feiras livres. A redução dos recursos destinados ao Programa de Aquisição de Alimentos (PAA) afetou negativamente na comercialização dos produtos das sementes crioulas. O engajamento de alguns pesquisadores e técnicos de extensão em projetos e/ou pesquisas, envolvendo sementes crioulas e em interação com os guardiões, se mostram promissores para uma maior conscientização dos agricultores e para a ampliação da utilização desse tipo recurso, muito importante para a conservação da agrobiodiversidade e para ampliar a autonomia dos agricultores familiares. / With the modernization of agriculture in the 1960s and 1970s, there was a substitution of landraces by commercially improved commercial seeds, usually associated with technological packages that included mechanization, synthetic fertilizers and agrochemicals. Landraces allow the farmer to maintain his or her diet even in times of climatic adversity, since they are adapted to the ecosystems in which cultivation takes place and increase their productive autonomy by being less demanding in relation to external inputs. The Território Prof. Cory/Andradina (SP) despite its historical characteristic of high concentration of land, presented advances in terms of deconcentration with the creation of almost forty rural settlements. The purpose of this study was to make a diagnosis of the production of landraces and to identify the landraces guardians in the rural settlements of the Território Prof. Cory/Andradina (SP). The socioeconomic aspects of the guardians, the local and traditional varieties conserved by them, the agricultural practices used, the destination of the production from the landraces, the methods of obtaining and exchanging them, and the performance of public institutions in the conservation of these materials were investigated. Were visited 28 rural settlements of the Territory, in the period between September 2017 and June 2018. The first stage consisted of the identification of some landraces guardians already known by means of key informants (extension technicians and researchers working in the area) so that from these guardians, by the "snowball" method, other guardians could be identified. The data collection was done through photographic records and a semi-open questionnaire (closed and opened questions), applied in the form of interviews with the identified guardians. For an analysis of the performance of public institutions in the conservation of agrobiodiversity, three professionals from entities operating in the Territory were interviewed. It was verified that the Território Prof. Cory/Andradina (SP) does not have a strong tradition regarding the conservation of landraces seeds, but some families maintain the habit of having their own seed, especially crops for self-consumption. A total of 55 guardians were identified in 24 rural settlements, with Cowpea bean being the most frequently found. The predominant destination of commercialization are the short circuits, in which stand out the individual sale to the consumer, the street market and. The reduction of resources allocated to the Food Acquisition Program (PAA) has negatively affected the comercialization of landraces products. The involvement of some researchers and extension technicians in projects and/or research, involving landraces and in interaction with the guardians, are promising for a greater awareness of the farmers and for the expansion of the use of this type of resource, very important for conservation of agrobiodiversity and to increase the autonomy of family farmers.

Orientador: Antonio Lázaro Sant'Ana / Resumo: Com a modernização da agricultura nas décadas de 1960 e 1970, houve uma substituição das sementes tradicionais cultivadas por sementes comerciais geneticamente melhoradas, geralmente associadas a pacotes tecnológicos que incluíam mecanização, fertilizantes sintéticos e agrotóxicos. As sementes crioulas permitem que o agricultor mantenha sua alimentação mesmo em épocas de adversidade climática, pois são adaptadas aos ecossistemas nos quais ocorre o cultivo e ampliam sua autonomia produtiva por serem menos exigentes em relação aos insumos externos. O Território Prof. Cory/Andradina (SP), apesar da sua característica histórica de alta concentração fundiária, apresentou avanços em termos de desconcentração com a criação de quase quarenta assentamentos. O objetivo deste estudo foi realizar um diagnóstico da produção de sementes crioulas, identificar os guardiões de sementes nos assentamentos rurais do Território Prof. Cory/Andradina (SP). Foram pesquisados os aspectos socioeconômicos dos guardiões, as variedades locais e tradicionais conservadas por eles, as práticas agrícolas utilizadas, destino da produção oriunda das sementes crioulas, métodos de obtenção e troca e a atuação de instituições públicas na conservação desses materiais. Foram visitados 28 assentamentos do Território, no período entre setembro de 2017 até junho de 2018. A primeira etapa constou da identificação alguns agricultores guardiões de sementes já conhecidos por meio de informantes chaves (técnicos da extensã... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: With the modernization of agriculture in the 1960s and 1970s, there was a substitution of landraces by commercially improved commercial seeds, usually associated with technological packages that included mechanization, synthetic fertilizers and agrochemicals. Landraces allow the farmer to maintain his or her diet even in times of climatic adversity, since they are adapted to the ecosystems in which cultivation takes place and increase their productive autonomy by being less demanding in relation to external inputs. The Território Prof. Cory/Andradina (SP) despite its historical characteristic of high concentration of land, presented advances in terms of deconcentration with the creation of almost forty rural settlements. The purpose of this study was to make a diagnosis of the production of landraces and to identify the landraces guardians in the rural settlements of the Território Prof. Cory/Andradina (SP). The socioeconomic aspects of the guardians, the local and traditional varieties conserved by them, the agricultural practices used, the destination of the production from the landraces, the methods of obtaining and exchanging them, and the performance of public institutions in the conservation of these materials were investigated. Were visited 28 rural settlements of the Territory, in the period between September 2017 and June 2018. The first stage consisted of the identification of some landraces guardians already known by means of key informants (extension technicians a... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-06-11T19:22:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-28Bitstream added on 2014-06-13T18:08:26Z : No. of bitstreams: 1 matos_er_me_ilha.pdf: 2466056 bytes, checksum: fd089ec7147abd26c94fadfe5e17bb85 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho apresenta-se uma Metodologia para Detecção e Classificação de Curtos-Circuitos em alimentadores de Sistemas de Distribuição de Energia Elétrica fundamentada na análise de registros oscilográficos através da DFT (Discrete Fourier Transform) e de RNAs (Redes Neurais Artificiais). Sua aplicação pressupõe a disponibilidade de registros de oscilografia digital das correntes nas três fases do alimentador, monitoradas apenas na saída da subestação. A caracterização de cada tipo de curto-circuito é obtida mediante a análise do comportamento dinâmico das correntes de fase durante o período transitório das faltas e a detecção e classificação dos curtos-circuitos são efetuadas por meio de um banco de RNAs acíclicas, do tipo perceptrons, de múltiplas camadas. Um modelo de um alimentador real de Sistema de Distribuição de grande porte, composto por 836 barras, foi utilizado na obtenção dos dados referentes aos curtos-circuitos, com simulações via software ATP-EMTP (Alternative Transients Program - Electromagnetic Transients Program). O método foi implementado e testado utilizando-se o software MATLAB®. Como resultado tem-se uma metodologia de formulação simples que apresenta bom desempenho, é de fácil implementação, apresenta baixa carga computacional e gera resultados altamente satisfatórios / This work proposes a methodology for Detection and Classification of Short-Circuits in Distribution Electric Power feeders, based on the analysis of oscillograph records through the application of DFT (Discrete Fourier Transform) and ANNs (Artificial Neural Networks). Its application requires the availability of digital oscillograph records of the currents in the three phases of the feeder, only monitored at the output of the substation. The characterization of each type of short-circuit is obtained by means of analysis of the dynamic behavior of the phase currents during the transitory period. The detection and classification of short-circuits is performed by a bank of acyclic ANNs, of type multilayers perceptrons. A real feeder model of a large distribution power system, composed of 836 buses, was used to obtain data relating to short-circuits, simulated via ATP-EMTP (Alternative Transients Program - Electromagnetic Transients Program) software. The method was implemented and tested using MATLAB®. As a conclusion, the proposed method is simple to be implemented, presents low computational load and generates good results

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-23T19:30:15Z No. of bitstreams: 1 2016 - Marcela Ferreira Rocha Lage.pdf: 2151978 bytes, checksum: 4d846b189d216d1c6f6b029f56113719 (MD5) / Made available in DSpace on 2017-06-23T19:30:15Z (GMT). No. of bitstreams: 1 2016 - Marcela Ferreira Rocha Lage.pdf: 2151978 bytes, checksum: 4d846b189d216d1c6f6b029f56113719 (MD5) Previous issue date: 2016-12-02 / From the year of 2002 eight (8) organic fairs were installed, in three regions of the city of Belo Horizonte - MG. The objective of the work is to survey the history, characteristics, the profile of family farmers / marketers and the profile of consumers and possible consumers of these fairs. It also seeks to analyze the difficulties for expansion in the production and marketing of the studied fairs. The study based on observations during the fairs and interviews using semi-structured questionnaires. There were 214 interviews with the attendees of the eight fairs. In addition to the questionnaire applied to consumers, five interviews were conducted with family farmers using another questionnaire and an interview with the supervisor of the Belo Horizonte City Hall. The results of the survey point to the existence of eight organic fairs, located in neighborhoods with higher per capita income, regulated by the Belo Horizonte City Hall with the participation of 5 (five) family farmers who face difficulties when it comes to required labor, the regularity of delivery and the quantity to be produced. The majority of the consumers were women between the ages of 30 and 54, with high schooling and monthly income, between 9 to 12 minimum salaries. Fairs are important channels for the commercialization of the organic production of family farmers and enable the proximity and establishment of trust relations between farmers and consumers mutually. / A partir do ano de 2002 foram instaladas 8 (oito) feiras org?nicas, em tr?s regi?es do munic?pio de Belo Horizonte ? MG. O trabalho tem como objetivo o levantamento do hist?rico, das caracter?sticas, do perfil dos agricultores familiares/feirantes e do perfil dos consumidores e poss?veis consumidores destas feiras. Procura-se tamb?m analisar os gargalos para a expans?o na produ??o e comercializa??o das feiras estudadas. O estudo foi realizado por meio de observa??es in loco e de entrevistas com o uso de question?rios semi-estruturados. Foram realizadas 214 entrevistas com os frequentadores das oito feiras. Al?m do question?rio aplicado aos consumidores, foram realizadas cinco entrevistas com os agricultores familiares/ feirantes com a utiliza??o de um outro question?rio e uma entrevista com o supervisor da Prefeitura Municipal de Belo Horizonte. Os resultados da pesquisa apontam para a exist?ncia de 8 (oito) feiras org?nicas, situadas em bairros com maior renda per capta, regulamentadas pela Prefeitura Municipal de Belo Horizonte com a participa??o de 5 (cinco) agricultores familiares que enfrentam dificuldades quando o assunto ? a m?o de obra necess?ria, a regularidade na entrega e quantidade a ser produzida. Os consumidores em sua maioria eram mulheres com idade entre 30 a 54 anos, com n?vel de escolaridade elevado e renda mensal da maioria dos entrevistados de 9 a 12 sal?rios m?nimos. As feiras s?o importantes canais de comercializa??o da produ??o org?nica dos agricultores familiares e possibilita a proximidade e o estabelecimento de rela??es de confian?a dos agricultores com os consumidores e vice-versa