塑料成型挤出机现场总线控制系统

Fieldbus Control System of Plastic Profile Extruder

通过分析锥形双螺杆塑料挤出机结构及其主要运行工艺参数,采用组合控制策略,根据系统误差及其变化率的大小自适应选择通断控制、模糊控制、积分控制等温度控制算法,设计一种挤出机温度控制系统。系统采用LonWorks现场总线实现网络化控制,应用效果表明,基于现场总线网络的多分区温度协调控制,改善了塑料挤出机的温度控制效果,可有效防止挤出过程中PVC-U物料的降解,从而提高了塑料产品成型品质。

By studying the structure and craftwork parameters of a taper dual-screw extruder, a combined-control strategy of onoff control, fuzzy-control and integral-control were adaptive elected following the temperature control error and its variety. LonWorks fieldbus were adopted to construct a net control system, so the extruder＇ s temperature sub-areas could regulated in line. Application effect shows that the method of multi-subarea control in line based on fieldbus has better effect than sub-areas control independently, and can prevent PVC-U decompounding effectively, so the character of PVC-U manufacture could be improved.