Research And Implementation Of Flexible Control System For Multi-Function Combination Dryer

This topic is based on the school-enterprise cooperation project of a chemical machinery company "control system transformation of multi-function combination dryer".Aiming at the equipment control system of the entire process sequence is fixed,the sequence of process unit can’t flexible adjustment,types of only a single,large batch of products production status,put forward a kind of flexible control strategy,the staff can according to the product characteristics,select the number of unit process and unit process order free combination,And can achieve no matter how the unit process is selected,the whole process production process can be automatically connected.The flexible concept is introduced into the actual production of the multifunctional composite dryer.Firstly,the control system scheme is designed and the hardware configuration of the control system is completed.On this basis,the flexible control strategy is put forward,and then the interface configuration,script writing and control program writing of the upper computer are carried out according to the strategy.The control system of multi-function dryer adopts three-layer network structure,the core of the control system is Siemens S7-300 PLC,and the monitoring level adopts PC workstation as the engineer station of remote central control room.The realization of the flexible control system of the multi-function dryer requires the configuration of the upper computer interface and the programming of the control layer.In this paper,Siemens software Win CC is used for the upper computer monitoring interface configuration,through the intelligent control combo box to achieve the selection and sorting of the product required unit process,using C language to write step process selection script,unit process start trigger script and unit process conversion script.For the control layer program,using programming software STEP7 to write,using ladder diagram language design controlled click equipment program,basic functions and unit process program;As the basic program,stand-alone equipment program,basic function program block and unit process program block can be unconditionally called by OB1 in the main program.The concept of structured programming makes the program structure of the control system clear,easy to debug and modify,and improves the programming efficiency.The Graph language of Step7 is used to write the sequential control program to realize the continuous execution of the whole production process.Based on the existing hardware equipment of the multifunctional combination dryer,the control system is deeply studied,and the flexible control system of the dryer is designed.The flexibility of the dryer control system is realized through the configuration of the upper computer’s operation interface and the design of the lower computer’s control program.After the technical transformation of the control system can reduce the difficulty of the staff,improve the degree of equipment intelligence,to meet the personalized needs of the market.