A new flux and stator resistance identifier for AC drive systems

The effect of stator resistance on AC motor drive performance is analyzed for flux vector and indirect field oriented controllers. A new technique-the back electromagnetic force (BEMF) detector-for reducing the adverse effects of stator resistance on field oriented control is presented and evaluated through simulation and experimental results. The BEMF detector is shown to reduce the impact of the stator resistance and provides a stator resistance estimate. The detector is compatible with most control strategies and with or without position feedback.