Continuous casting crystallizer fluid level control method based on Fuzzy-PID

Abstract

The invention relates to a method for controlling the liquid level of a continuous casting crystallizer based on Fuzzy-PID. In the method, the liquid level is controlled by auto turning parameter PID control and fuzzy control under the control of a computer and a PLC, and the mechanical dead area is compensated. The method comprises the following steps: step 1, the original liquid level y0 is set, and the liquid level y1 and y2 are collected by a liquid level controller and a liquid level sensor; step 2, the collected data y1 and y2 are input PLC by a signal processor, the data is processed by the mixed control of the auto turning parameter PID control and the fuzzy control, and the mechanical dead area caused by insensitivity of the machine transmission is compensated by adjusting the PID parameter; step 3, the PLC outputs u(k)=u1(k)+u2(k), so that the liquid level is controlled by controlling the position of a stopper by a stopper controller. The method of the invention ensures that the system not only has good steady characteristic, but also has excellent transient characteristic under time-variation condition by reasonably designing fuzzy control rule and parameter setting rule.

Description

technical field [0001] The invention belongs to the technical field of continuous casting production, in particular to a method for controlling the liquid level of a continuous casting crystallizer based on Fuzzy-PID. Background technique [0002] With the technological progress of the steel industry, the market's requirements for the quality of steel products continue to increase. As an important link in the steel production process, continuous casting directly affects the quality of steel products. The change of the molten steel level in the continuous casting mold has an important impact on the quality of the slab, and stabilizing the liquid level in the mold is of great significance to improve the quality of the slab and improve the casting effect. During the continuous casting process, the liquid level of the mold should be kept within an appropriate range. If the molten steel level rises, it is equivalent to increasing the immersion depth of the casting nozzle, increas...

AI Technical Summary

Problems solved by technology

In theory, the control method of switching between PID controller and fuzzy controller comprehensively utilizes the good steady-state performance of PID controller and the good transient performance of fuzzy control, but the uncertainty of the system in the actual production process makes the PID controller It is difficult to adapt, and the disturbance impact brought by the switching process of PID control and fuzzy control also increases the disturbance of the system correspondingly, which is easy to cause frequent occurrence of overshoot

Images