The Design Of Intelligent Valve Positioner Hardware System

In modern industrial automation control, the quality of industrial process control depends to a great extent on the performance level of process control instrumentation. Pneumatic control valve is an important governor motion of industrial process control, and the intelligent valve positioner studied in this paper is the main attachment of pneumatic control valve, it can significantly improve the dynamic characteristics of valves, improve the control speed, precision and flexibility of valves.From the produce of valve positioner in the mid-twentieth century, it has experienced several different development stages. At present intelligent valve positioner is the focus of domestic and foreign research and use. The hardware part of intelligent valve positioner was studied and designed in this paper, and the composition of positioner hardware control system and the characteristics of the main module were systematically studied, The following main achievement are yielded:1,Based on the domestic and foreign research about intelligent valve positioner, by means of the deep analysis of the structure of typical intelligent valve positioner, the principle of operation and implementation functions, the scheme of positioner hardware system which used LPC2290 as the centre was draw up and the performance index of positioner hardware system was pre-estimated.2,The characteristics analysis of the hardware system of intelligent valve positioner was carried on. Based on mathematical modeling, the dynamic and static characteristics analysis of the main module of the designed intelligent valve positioner were carried on. The principle of operation of various parts of the module and the influence to the function of positioner control system were explained by theory.3,By means of previous work, the positioner hardware system was designed in detail. The hardware circuit module which used LPC2290 as the core were designed and implemented according to the requirements of intelligent valve positioner hardware control system. And the simulation experiments about designed function circuit were carried on by means of the powerful electronic circuit simulation software Multisim, The relevant circuit parameters were analyzed, the PCB board about critical signal conditioning circuit were made, actual tests were done, the expected results of circuit performance test were achieved. Through the design and analysis of the entire hardware system circuit, the pre-established overall design of the intelligent valve positioner hardware system was achieved finally.