Design On Advanced Control System Based On Foundation Fieldbus And Realization

Foundation Fieldbus (FF) is one of the most prosperous Fieldbuses at present, andresearch on FF has already become the key aspect in the engineering and academicfields. In this paper a suit of process control system based on FF and advanced controlalgorithms is carried out to solve the problem 'Design on advanced control systembased on Foundation Fieldbus and its realization' associating with our laboratoryconstruction. And the products from Shenyang automation research institute ofChinese Academy of Sciences are adopted in the control system. It is of moreimportance for us to adopt advanced control algorithms, beyond PID algorithm, tosolve problems in the control of plants with time delay in the FF system. The aim is todesign the monitoring and control software system while associating the advancedcontrol algorithms with FF system, which can exerit their respective technologicalmerits better.The main contents of this paper are as follows:Firstly, the development on FF, monitoring and control soflwares and advancedcontrol algorithms is introduced, the necessity and significance of advanced controlbased on FF in the automation is also analyzed, and the key technologies involved inFF are further researched; What is more, the system architecture is researched as wellas the composition and function of function blocks, so that the corresponding theory onprocess control platform based on FF is set up. Secondly, process control system basedon FF is constructed, the corresponding parameters of all sorts of function blocks areresearched and the basic platform is set up for further researching. With regards to thetime-delay system, predictive control and its improved algorithms are studied,Dynamic Matrix Control (DMC) and neural network control are introduced and their advantages and disadvantages are also analyzed respectively. So a new DMCalgorithm based on BP neural network is proposed and the neural network is used ascontroller and predictive model respectively. Furthermore, OPC DA 2.0 specificationand realization in OPC data server are studied as well as the architecture of monitoringand control software based on OPC. At the same time a database stroing real-time orhistory data is also set up in order to collect the data from OPC server. Advancedcontrol algorithm and its improved algorithms are done with the collecting data. Thenthe platform based on FF and OPC is set up to realize the advanced algorithm. Finally,the second development process of OPC DA interface based on OPC and Matlab isstudied as well as the realization of DMC and DMC based on neural networkalgorithms. Especially, the problem on communicating among client, OPC server andSQL Server 2000 database is also solved in Matlab, and the valididty of the abovecontrol algorithms is compared and the realization scheme based on advanced controlalgorithm in Matlab is set up as well and then put into the double-holding loop liquidlevel control system. And the result is as we always predict.