Research output: Contribution to Journal/Magazine › Journal article › peer-review
<mark>Journal publication date</mark> | 1/01/2014 |
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<mark>Journal</mark> | Tobacco Science and Technology |
Issue number | 1 |
Volume | 2014 |
Number of pages | 5 |
Pages (from-to) | 26-30 |
Publication Status | Published |
<mark>Original language</mark> | English |
In PID and feedforward control systems, the control loops for moisture content in dried cut tobacco are relatively independent of each other, low in control precision, poor in coordination and hard to be integrated into a full closed-loop automatic control. A model-based predictive control method was proposed, the model of the dynamic characters of drying process was created by RBF-ARX model. According to production process and technology, drying process was divided into 3 stages (start, middle and finish stages), and controlled by model-based optimized setting or predictive control method separately. To obtain optimal technical parameters, the combined influence of cylinder temperature and moisture exhaust acted at the same time on the moisture content of tobacco was taken into account. The results of application showed that: 1) The drying process was automatically controlled, and interference became unnecessary. 2) The moisture content in tobacco at start and finish stages was controlled within the set value ± 0.5%, at middle stage was controlled within the set value ± 0.2% with the standard diviation of no more than 0.10%, and the fluctuation of moisture content caused by various disturbances could be restrained quickly. 3) The amounts of over-dried tobacco at start and finish stages in a drying operation were less than 0.27% and 0.28% of throughput; the waste and breakage of tobacco reduced. The model-based predictive control method was better than controlling cylinder temperature and moisture exhaust independently, and better fit the requirements of industrial application.