双螺杆挤出机温度控制系统的设计与优化

Design and optimization for temperature control system of twin screw extruder

双螺杆挤出机运行稳定性、各参数的控制精确性对于其正常运行以及挤出产品产量和质量均有很大影响。采用不依赖调整规则的变论域方法与模糊比例积分微分(PID)控制相结合,对双螺杆挤出机温度控制系统进行设计和优化,提高温度控制系统的容错能力。通过建立一个通用的控制对象的数学模型,采用实验方法对数学模型的各参数进行确定。最后,将变论域模糊PID控制与常规PID控制和模糊PID控制进行对比,研究变论域模糊PID控制的性能。结果表明:与常规PID控制相比,使用模糊PID控制对温度控制效果明显增强,而使用变论域模糊PID控制的控制效果最优。

The operation stability and the accuracy of parameter control are important for the normal operation of the twin screw extruder as well as for the output and quality of the products. The design and optimization for the temperature control system of the extruder are carried out by use of variable universe of self-adaptive rule and fuzzy proportional integral differential（PID） controll to improve the fault tolerance of the temperature controller. A general mathematical model of controlled object is established and whose parameters are identified through experimental method. Finally the variable universe fuzzy PID controller are compared with the conventional PID and fuzzy PID controller to observe its control performance. The results indicate that the control effect of the fuzzy PID controller on the temperature enhances remarkably in comparison to the conventional PID controller, and control effect of the variable universe fuzzy PID controller is the best.