An Intelligent Cooperative Decoupling Controller for Coagulation Bath in Polyacrylonitrile Carbon Fiber Production

The production of polyacrylonitrile carbon fiber (PANCF) consists of a set of industrial processes with high complexity. A key process is the coagulation of the PAN as-spun fiber in the coagulation bath which has a lot of variables coupling with each other. In this paper, an intelligent cooperative decoupling controller (ICDC) based on the neuroendocrine regulation principle of human body is proposed and applied to the coagulation bath in the PANCF production. Three important variables including the liquid-level, the temperature, and the concentration are considered. The ICDC consists of a control center unit, several control and decoupling units and their corresponding output units. The control center coordinates each control and decoupling unit and determines their control schemes. Each control and decoupling unit takes effect independently, and the control information is exchanged among them for decoupling. The control signals are then integrated at the output units and finally sent to the plant. Simulation results demonstrate that the ICDC can rapidly response to the variation of control variables, completely eliminate the coupling influence and make smooth regulation without overshoot, which has a better performance than the conventional control schemes.