Temperature Control System Research And Design Of Car’s Body Painting Oven

With cars has been a necessity of life, most of foreign cars manufacturers established factories for a huge consumption demand of China, which aggravate the competition of cars industry. Domestic cars manufacturers increased technology input and improved craft production efficiency so that their comprehensive competition and automation degree was enhanced gradually. Cars drying is a very important production procedure in painting workshop, the inner temperature of drying oven made an significant effort to whole drying process, the automobile body passed temperature increasing area, temperature holding area and strong cold area, process temperature must be follow preset temperature as soon as possible to make sure car’s surface quality. The temperature of drying oven was used as the research subject in this paper, control system was designed based on PLC technology, OPC communication and fuzzy self-tuning PID algorithm.Firstly, the overall structure of drying oven and hot wind recycle drying principle was introduced, craft principle of combustion group and heating group were analyzed, then the pattern of lower side air supply and upper side back was selected after comparing various kinds of common hot air circulation, the temperature sensor was installed at a appropriate position according to qualitative analysis. In view of the present car coating chamber adopts PID temperature control method in the presence of parameter setting, and poor adaptability complex faults, the fuzzy control algorithm is applied to PID control parameters setting process, and under the environment of Simulink simulation controller structure building and interior design of the fuzzy controller, the given approximate mathematical model to simulate the coating chamber temperature control system, a comparison before and after the improved control algorithm of control effect. Secondly, hardware and software design was accomplished. In view of the present car coating chamber adopts PID temperature control method in the presence of parameter setting, and poor adaptability complex faults, the fuzzy control algorithm is applied to PID control parameters setting process, and under the environment of Simulink simulation controller structure building and interior design of the fuzzy controller, the given approximate mathematical model to simulate the coating chamber temperature control system, a comparison before and after the improved control algorithm of control effect. The OLM ring redundancy network topology and Profibus-DP/fiber interface implementation PC station, communication between PLC station and field intelligent devices. And then introduced the STEP 7 software project development process, coating chamber temperature control system of PLC control process is analyzed, according to the program flow chart of program structure, complete the initialization, combustion control, the heating group control, fan air valve control program written. To make the system can achieve rapid human-computer interaction, with the aid of Kingview software for the design of upper monitor interface.Finally shows how to use OPC communication technology to realize information interaction between the OPC server and client, in order to realize the Matlab algorithm is combined with an efficient operation and PLC logic control of the two as OPC client, through the OPC server implementation indirect communication of the two. Based on OPC communication implement chamber temperature fuzzy self-tuning PID control and the monitoring test results were analyzed.