Improved performance of rolling mill drives using hybrid fuzzy-PI controller

In this paper, a fuzzy logic control technique is applied to solve the undesired undershoot that gets the process in special steel rolling mill out of control. Because fuzzy logic controller results in steady state error due to load change two control methods are proposed to improve the fuzzy controller performance. The first method uses a fuzzy speed controller with a PI current controller and the other method uses a hybrid fuzzy-PI controller. The proposed hybrid fuzzy-PI controller is applied to a rolling mill drives. This technique can solve the common problems associated with rolling mill drives. The entire drive systems are implemented using a high speed digital signal processor (DSP). Experimental results validate the theoretically simulated responses with different operating conditions.