1、英文原文FUZZYDECOUPLING CONTROL OF MELTTEMPERATURE AND MELT PRESSURE FOR PLASTICELECTROMAGNETISM DYNAMIC EXTRUDERWEN Shengping，QU JinpingNational Engineering Research Center of Novel Equipment for Polymer Processing，Dept of Industrial Equipment and Controlling ,South China University of Technology，Guang
2、zhou 510640,ChinaKeywords: Melt temperature， melt pressure, fuzzy decoupling control, electromagnetism dynamic extruder.AbstractThe plastic electromagnetism dynamic extruder has gained wide applications because of its novel structure and fine engineering performance。In the polymer processing，melt te
3、mperature and melt pressure control is crucial to the quality of the extruded product。A new fuzzy decoupling control algorithm of melt temperature and melt pressure for the novel extruder is introduced in the transfer function matrix system,which is obtained through the experimental data with system
4、 identification。The control system is implemented on programmable computer controller。Experimental results show melt temperature and melt pressure can be successful individually controlled by the heater power and the screw speed。The good system performance verifies the control strategys validity。1 I
5、ntroductionPolymer extrusion is a complex nonlinear multivariable coupling process。There are many factors affecting the stability of extrusion process and the quality of extruded products。The equipment is the crucial factor。There are already many kinds of extruder。Unlike the traditional extruder。a n
6、ew kind of electromagnetism dynamic extruder was invented by professor Qu Jinping5.He introduced the vibration force field into the whole process of polymer extrusion。The vibration force field brings new changes to the energy balance，quality balance and momentum balance of the whole extrusion proces
7、s。Control of vibration frequency and vibration magnitude can effectively control the dynamic extrusion process。The electromagnetism dynamic extruder is shown in Fig.l，Researches on the dynamic extruder show the good performance of the machine。Besides the extruder，melt pressure and melt temperature a
8、re key variables to the extrusion process。Melt pressure directly influences the output of the product。While melt temperatures fluctuation can change melt viscosity and consequently influences melt pressure and flow rate. Therefore，the dominant variables are melt temperature and melt pressure in the
9、dynamic extrusion process.Fig.l: the structure of electromagnetism dynamic Plasticating extruder.1 screw,2 barrel,3 rotor,4 stator,5 support base,6 hopperIn order to get high product quality，control of melt pressure and melt temperature for the traditional extruder has been done with different contr
10、ol method。In 1970s，Dormeier，S.4 firstly introduced the digital PID control to melt Temperature cascade control。The diameter of the screw is 45mm.Because of the limit of hardware development，the sample period is 15s.The cascade PID control is shown in Fig.2.Fig.2: melt temperature cascade PID control
11、.ntroduced into the barrel-wall temperature control。Richey Dubay，Adam C.Bell and Yash P.Gupta used model prediction method to establish the multiple-input multiple-output model for the temperature control of the different sections of the barrel6.Ching-Chih Tsai and Chi-Huang Lu investigated the mult
12、ivariable temperature control of the barrel based on the generalized predictive algorithm2.The mathematic model of the heating process shown in Fig.3 was built according to the energy balance。Chi-Huang Lu also adopted the self-adaptive prediction control to the barrel temperature control3。Achievemen
13、ts gained were mainly about the traditional extruder。Melt temperature and melt pressure control of the electromagnetism dynamic extruder has seldom reported by now。Melt temperature and melt pressure control based on a new fuzzy control algorithm for the electromagnetism dynamic extruder is investiga
14、ted in this paper.Fig.3: physical model of the extruder barrelAchievements gained were mainly about the traditional extruder。Melt temperature and melt pressure control of the electromagnetism dynamic extruder has seldom reported by now。Melt temperature and melt pressure control based on a new fuzzy
15、control algorithm for the electromagnetism dynamic extruder is investigated in this paper.2 Modelling of the systemThe electromagnetism dynamic extruder has five heating zones。Temperatures of the first four heaters are set by manual。The temperature of the heater on the die is to be controlled by the
16、 new control strategy。There are five thermocouples positioned in the barrel-wall to measure the barrel wall temperature。One infrared temperature transducer is positioned nearest the exit of the melt to measure melt temperature。Melt pressure is measured by a strain-gauge-type pressure transducer positioned in the die-wall。Melt pressure is controlled by screw speed。Step response of m
