Four-tank System Equipment Design And Algorithm Research

With the development of production and technical level, an increasing number of complex plants are applied to actual production process, which have the characteristics of time delay, nonlinearity and coupling. Since simple control algorithms, such as PID controller, can not deal with the control problems of complex systems well, it is necessary to look for advanced control algorithms to achieve better control performances. If advanced control algorithms are lack of practicality experiment, it will be a long period to put it into practical use. Therefore it has important practical significance to design a suit of experiment device with some industrial backgrounds according to the characteristics of typical objects in process control.In order to meet the needs of teaching and academic studies on Automation, a set of four tank experimental device is designed and developed. In this thesis the experimental device is made up of hardware and software systems. The industrial computer, PCI data acquisition card, input type liquid level sensor, diaphragm pumps and other common equipments related to industrial production are used to build a hardware platform. The software system is implemented by MATLAB software, and the modular design is carried out according to the system functional characteristics. Taking the advantage of powerful data processing ability and good support for hardware of MATLAB software, communication and control requirements of the system are realized by programming on MATLAB software. In addition, a visual operating interface is designed base on MATLAB/GUI to realize the integration of four tank system. By using this operating interface, parameters configuration, data acquisition and storage, dynamic display of control process can be done. Furthermore, the transplantation of software system is studied so that the software system can be used without MATLAB environment.In this thesis, the mechanism model of four tank system is introduced, and the parameters associated with the system transfer function are obtained by system identification. According to the characteristics of the four-tank system, an internal model controller based on the identification model and a H∞ state feedback controller based on mechanism model are designed, respectively. Finally the designed controllers are applied to the four tank system, and some related experiments are conducted. The results are obtained in the experiments and the purpose of the design of the experimental device is achieved.The experimental device is a platform, which can be used to verify various advanced control algorithms. Thus it provides a simple experimental device for students and researchers.