烘丝过程烟丝含水率的MFA控制

烘丝过程中烟丝含水率的变化具有较强的非线性、不确定性和大滞后特性,同时存在干扰和噪声,运用常规的PID算法难以达到期望的控制效果。采用无模型自适应控制器(MFA)并结合渐进辨识(ASYM)方法对烘丝过程的烟丝含水率控制系统进行了改造,建立了前馈和含水率对象的数学模型,提高了模型的精度。利用MFA的自适应和抗滞后功能,减小了烟丝含水率的波动幅度,降低了“干头干尾”的数量,提高了卷烟生产质量。

MFA Control of Moisture Content during Cut Tobacco Drying

The nature of the variation of cut tobacco moisture content during drying, its strong nonlinearity, uncertainty, longer time lag, accompanied with disturbance and noises, precluded the conventional PID algorithm from attaining the expected results. The MFA (model free self-adaptive) controller combined with ASYM was used to improve the moisture content control in cut tobacco drying, and the mathematical model of feedforward and moisture content object was established. The precision of model was increased. By means of the self-adaptability and anti-lag function of MFA, the fluctuation range of moisture content of cut tobacco was decreased, the amount of over-dried cut tobacco during start and finish of drying operation were reduced, and cigarette quality was improved.