A fuzzy logic controller for stator neutral switching of induction motor drives

The paper presents a novel feedback closed loop speed control scheme for internal-cycle ON/OFF voltage regulation of induction motor using an artificial intelligence fuzzy logic controller (FLC). The scheme accommodates an integral-cycle ON/OFF switching strategy. Only one controlled chopper MOSFET switch is utilized compared to the other methods which use more than one controlled device. The new technique is very simple and less costly. The triggering circuit of the MOSFET switch ON/OFF control is designed and tested using small electronic components. A comparison between a conventional PI controller and the proposed FLC is presented for both digital simulation and experimental testing. The digital simulation results prove that the FLC improves the speed tracking and reduces the rise time and overshoot/undershoot excursion