精密挤出成型过程中的多变量模糊解耦控制

Multivariable Fuzzy Decoupling Control of Precise Extrusion Processing

在聚合物精密挤出成型加工过程中,机头熔体温度与机头压力是影响精密挤出成型制品质量的关键因素.文中通过动态特性实验,采用系统辨识的方法,建立了机头熔体温度与机头压力关于机头加热器功率与螺杆转速的输入输出传递函数矩阵模型,提出了一种熔体温度与机头压力的模糊解耦控制算法,并采用可编程计算机控制器予以实现.通过在挤出装置上进行的运行实验验证了该模糊解耦控制算法的有效性,有助于推动精密挤出成型控制技术的发展.

In the precise extrusion processing of polymers, the melt temperature and the pressure in the die constitute a key factor to the quality of the extruded product. In this paper, some dynamic characteristic experiments were carried out, and a transfer function matrix model was established according to the experimental data obtained via system identification. The model was used to describe the relationships between the input signals related to melt temperature and die pressure and the output signals concerning heater power and screw speed. Then, a fuzzy decoupling control algorithm of melt temperature and die pressure for the precise extrusion processing was proposed and finally implemented on a programmable computer controller. Experimental results show that the proposed algorithm is effective and contributes significantly to the development of the control technology of precise extrusion processing.