在封装机系统分切的过程中,由于放卷辊上包装纸的直径越放越小,放卷机系统的转动惯量的变化范围很大,采用一般的控制方法难以取得满意的控制效果。本文详细分析了包装纸放卷过程中的受力(尤其是张力)情况，并建立了数学模型，利用自适应控制原理很好的实现了送料过程中的张力控制。关键字: 自适应控制, 张力, PLCAbstract: In the process of parting cut of packaging system, the rotational inertia is of a big range because the parameter of the packaging paper is becoming smaller. Traditional control method can hardly make a good effect to solve this problem. In the paper, the tension situation in the process was analyzed in detail and a mathematical model was established as well. And then we used to self-adaptive method to control the tension and obtained a good result.Keywords: Self-adaptive Method; Tension; PLC