Stability analysis of I-f startup method for PMSM drive systems

In low-cost permanent magnet synchronous motor (PMSM) drive systems, the rotor position is usually estimated based on the back-electromotive force. However, such estimation methods have the common drawback of having large errors in low-speed regions. In order to solve that drawback in the startup phase, the I-f startup method is studied as its compatibility with the FOC control structure.