Research On Strip Steel Guiding And Control System Of Coating Furnace

In the strip steel production line, strip steel guiding devices are essential equipments, and they have the important meaning in regarding the safeguard strip steel production quality and guaranting the trouble-free transmission. This topic aims at carrying on the design and the improvement on steel strip guiding control system of coating furnace in some silcon steel factory heat treatment production line.Through sitevisits, the working environment is that the coating furnace temperature is about 500 degrees, and the mouth of coating furnace temperature is 150 degrees or higher, worse conditions. The original strip steel guiding devices are pneumatic devices, impacting in a big way. the air cylinder is easy to damage, and the air valve is extremely easy to stop up. Often because of the breakdown, causes the parking: moreover because the maximum-guiding, creates collision marks extremely easily on the edge of a strip, or scratches the strip surface, affecting the product quality.In view of the main problems existing in the original strip steel guiding devices, this article makes the improvement on the following several aspects.Firstly, using the hydraulic servo devices to replace the original pneumatic devices to promote the corrective roller has been proposed. The major work is the design of hydraulic servo system schematics, according to control system's essential requirements, carring on the type for the main hydraulic components, and doing the check of the designing hydraulic system.Next, considering the question of the hydraulic system's model, one kind more accurate and the advanced modelling method has been adopted in this article. According to hydraulic system's pressure balance equation, the flow continuity equation as well as the strength balance equation, subsystems such as the hydraulic pump, the overflow valve, the servo valve, the hydraulic cylinder and the cavity model in Simulink have been established, also according to the working principle, the simulation model is built, and through the parameter definition interface, the model parameter can be revised conveniently.In the design of control algorithm, this article has some certain pointedness. During strip steel offset signal in gathering process, because that the coating furnace outlet's temperature is above 150 degrees, the temperature is high, and the site equipments constraint sensor's installment, sensor's actual installment position is 5 meters far away from coating outlet, and the lag examination plan has been proposed. Regarding the introduction of the pure delay link, basing on the Smith predicting compensation fuzzy PID control algorithm has been studied in this article.During the simulation process, disturbance conditions to the system such as exerting the perturbation, creating the model mismatch and changing the model parameters separately, the detailed analysis and the comparison on the simulation curves based on PID, PID-Smith, fuzzy PID-Smith controller have been made. Finally the conclusion has been drawn: using fuzzy PID Smith controller. Smith is realized to the delay characteristics compensation; replacing the ordinary PID controller by fuzzy parameters self-adapt PID controller, could display the fuzzy controller's flexibility and PID controller's high accuracy, thus further increase system's precision and stability.The aspect on realizing the algorithm software, Programmable Logic Controller which has been suitable in the industrial control field has been chosen in this article. The PLC hardware equipment's selection for the control system has been carried on, and the strip steel guiding control algorithm has been realized through the software programming.Finally, in the laboratory the tested platform has been completed and the simulation and summary to the experiment process have been made. The experiment has proven, because the fuzzy PID-Smith control algorithm which has the higher reliability and better suited in this run-time system has been used, the system's control precision, the movement stability, and the reliable aspect all have been enhanced a lot, and the system has the better anti-interference ability and robustness.