Efficiency-optimized direct torque controlled integrated starter/alternator with power factor tuning

This paper presents a novel efïîciency-optimized scheme based on power factor tuning for the Direct Torque Controlled Integrated Starter/Alternator. The power factor of the induction machine is controlled to track the pre-determined power factor reference without requiring any speed or load information. Two power factor estimation methods are proposed. The power loss is minimized with proper power factor control under different conditions.