Abstract:
In order to control the moisture content in tobacco strips in screening and casing process precisely, the moisture content control system was upgraded with a control algorithm based on self-adaptive fuzzy feedforward-feedback mechanism. The feedforward input water flow was calculated according to the delayed moisture content in input tobacco, delayed instantaneous input tobacco flow, instantaneous steam flow, instantaneous casing flow and their fluctuations; the feedback input water flow was calculated on the basis of current moisture content in output tobacco; the current input water flow was the sum of the two and from that the opening of the respective valve was determined. Cigarettes of three brands were tested in Shijiazhuang Cigarette Factory, the results showed that the moisture content in output tobacco did not fluctuated obviously, the process capability index CPK increased by 75%, and the standard deviation decreased by 36%. This method provides a technical support for promoting the consistency of cigarette manufacturing.