This paper presents a modified self-tuning fuzzy controller with union rule base for application in the switched reluctance motor (SRM) drive system. Based on the redevelopment of control rule base, this paper aims to simplify the programme hierarchy and computational complexity of the controller by reducing the number of fuzzy sets in the membership function (MF) without losing the system performance and stability. With the error and change of error as the input variables, the output scaling factor (SF) of the proposed controller can be adjusted continuously via a gain updating factor, whose value is derived from the fuzzy logic reasoning. The controller is implemented based on the dSPACE DS1104 control desk. Experimental results show that the proposed controller is in good agreement with theoretical derivation. Comparisons with the conventional PI-like fuzzy controller (PIFC) demonstrate that the effectiveness of the devised control scheme outperforms its conventional counterpart.
Keywords: fuzzy logic controller, FLC, scaling factor, switched reluctance motor, SRM