Temperature Uniformity Control of Large-Scale Vertical Quench Furnaces for Aluminum Alloy Thermal Treatment

Abstract

The thermal treatment of aluminum alloy workpieces requires strict temperature uniformity in large-scale vertical quench furnaces. To achieve the desired temperature uniformity in a large-scale spatial setting, a temperature uniformity control strategy combining workpiece temperature compensation and intelligent proportional-integral-derivative (PID) decoupling control is presented. The temperature compensation of the workpiece is realized by establishing an air heat conduction model. Moreover, an intelligent PID decoupling control system based on a novel self-growing radial basis function neural network (SGRBFNN) is developed to eliminate the strong coupling effects of multiheating zones. SGRBFNN, with the structure being dynamically adjusted by a hybrid semifuzzy Gustafson-Kessel clustering algorithm, is proposed to realize the online tuning of the parameters of the PID controller. Both the simulation and industrial experiment results demonstrate that the proposed temperature control system can effectively achieve smooth regulations and significantly improve temperature uniformity. The application also demonstrates the validity and better control performance of the proposed system compared with conventional control systems.