The Research On The Control System Of The Spray Deposition Tubular And Tundish Level Control

Spray deposition is a new kind of near-net shape metal forming technology which is used to manufacture rapid solidification advanced materials with the characteristics of uniform composition, high density, low oxygen tension and small degree of segregation. This technology has been coming into industrial scale production in Europe, American and Japan, while domestic research in spray deposition technology is still basically staying at a laboratory or experimental stage. Domestic research in automatic control and intelligent control of spray deposition process has already been launched, but there is still a certain distance to industrial scale production.The characteristics of utilizing spray deposition technology to manufacture large dimension tubular product was analyzed in the present thesis, the structure of spray deposition device of tubular preform and its main operational principle were studied on, and the three layer hierarchical control structure consist of the management system layer, control system layer, and field device layer was constructed. To meet the demands of the technics of the Spray Deposition, the configuration of the control system of the Spray Deposition was provided, and the design, development and debug of the control program and the monitor program were finished.The structure and control strategy of the exactly level control based on PID method were put forward in the thesis, the detailed mathematical model of the tundish level control system was established. The self-adaptive genetic algorithm, which based on the fuzzy logic, is studied to optimize the PID parameters based on the platform MATLAB.The result of the research has been applied in the real control system and has good performance. According to the data collected from the field, the time of PID regulating is about 30 seconds, level undulating quantity is less than 10 millimeters, steady state error is±3 millimeters. The system is characterized with fast response, small overshoot, steady level and good control precise.