O uso da lógica fuzzy no controle das temperaturas de um conjunto gaseificador/combustor de biomassas

• Autor(a) principal: Rezende, Oscar Luiz Teixeira de
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/719
• topic: Energia na agricultura; Controle de temperatura; Energy in agriculture; Control of the temperature; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA

This study consisted in designing and building a concurrent biomass gasifier that, when attached to a gas combustor, produced a mix of hot air and ambient air to be used for drying grains, among other things. It aimed at controlling the combustion zone gasifier temperature and exhaust hot air temperature. The theoretical mathematical framework chosen to develop the algorithm to temperatures control of the set gasifier/combustor was Fuzzy Logic System, which uses fuzzy logic concepts to model processes based on the empirical knowledge of specialists in a particular study field. The set gasifier/combustor was assessed at the DEA/UFV Alternatives Energies Lab. Eight experimental tests were carried out. The first two were preliminary tests to assess the gasifier design and collect data to support the construction of Fuzzy Logic Systems. The next four tests intended to assess efficiency of the Fuzzy Logic Systems and keep gasiefier combustion zone and exhaust air temperatures of the set gasifier/combustor at desired values. The last two tests assessed the Fuzzy Logic System responses to situations in which instability in gasification combustion zone temperature was caused by using, simultaneously, in the same test, different types of fuel. Temperature data at different points of the gasifier/combustor were collected during the tests. The statistic methods used for assessing Fuzzy Logic System efficiency were: temperature data variability and Student t-test, to compare average temperature of temperature data and the reference value, setpoint. The results showed that the Fuzzy Logic Systems effectively controlled the gasifier combustion zone and exhaust hot air temperatures, which enables its use for drying grains and other purposes.