A Sliding Mode Flux Observer for Direct Torque Controlled Integrated Starter/Alternator

This paper presents a sliding mode flux observer for a direct torque controlled integrated starter/alternator. The sliding mode observer is designed to estimate the stator flux based on a simplified model of induction machine without requiring any speed information. Compared with open-loop flux estimator, the sliding mode observer ensures that the flux estimation is robust to the stator resistance variation and sensors offset. Simulation and experimental results are provided to verify the performance of proposed sliding mode observer for both steady state and transients