Automated control of the preform reheating process in the manufacturing of poly(ethylene
terephthalate) containers. Part II. Identification of the dynamical properties of controlled object
Polimery 2013, No 2, 121
The paper is the second part of a series presenting the research work focused on the development of automatic temperature control system for poly(ethylene terephthalate) (PET) preforms in the reheating process. The methods and results of the identification of dynamical properties of the controlled object were described. The constructed dynamical models were presented and their consistency with the experimental data was verified. It was found that the processes which occur during reheating of performs are characterized by a relatively high inertia, which is the main reason of low quality of manual control by an operator. The results of the statistical quality assessment of an exemplary reheating process running in open-loop mode were presented. They show that it is necessary to develop an automated temperature control system for the process of heating the preform. An original concept of supplemental signal, as an indirect measure of thermal conditions inside the heating oven, which can increase a dynamical quality of automatic control, was discussed.