Το work with title Energy efficiency and quality control of polymer extrusion process based on intelligent control techniques by Bitirini Maria is licensed under Creative Commons Attribution 4.0 International
Bibliographic Citation
Maria Bitirini, "Energy efficiency and quality control of polymer extrusion process based on intelligent control techniques", Diploma Work, School of Electrical and Computer Engineering, Technical University of Crete, Chania, Greece, 2018
https://doi.org/10.26233/heallink.tuc.78344
Polymer extrusion, in which a polymer is melted and conveyed to a mould or die, forms the basis of most polymer processing techniques. Product quality is a major issue of concern of processors. The product quality in polymer extrusion process is largely depended on melt viscosity. The real time monitoring and control of viscosity is a difficult procedure due to the plant non-linearities. In this thesis, a model control prediction between velocity (dependent variable) and the temperature sensor readings (independent variable) with statistical methods is proposed. The controller output is the convenient velocity regulation based on an error signal input, which is generated by real time measured velocity and the real time predicted velocity calculated from a mathematical model which is based by the temperature sensors readings. As mathematical models, Arrhenius-Exponential model (where the non-linear model converts to linear) and ANFIS model are proposed, with both of them being novel approaches for the polymer extrusion process. The final velocity model prediction is a non-linear dynamic model, with four inputs for its prediction (i.e. barrels points temperatures). The velocity regulation achieves die melt temperature stabilization (eliminates the melt temperature variance) by succeeding the desired die melt average temperature. This novel feedback structure enables the online adaptability of the velocity model in response to modeling errors and disturbances, hence producing a reliable velocity estimate.