Rotor position estimation method of IPMSM using HF signal injection and sliding‐mode controller

This paper presents a simplified algorithm for the estimation of rotor position. A high‐frequency (HF) sinusoidal voltage is injected into the stator of a motor. An interior permanent magnet synchronous motor (IPMSM) has spatial saliency because the d‐ and q‐axis inductances are different from each other. The injected HF voltage is influenced by this saliency. Therefore, the rotor position is included in the stator current of the motor. The proposed method uses different synchronous reference frame transformations (SFTs) to extract the rotor position error between the estimated value and actual value. Also, a sliding‐mode controller is used for robustness against parameter variation and external disturbance. The experimental results confirm the effectiveness of the proposed method by showing waveforms of the rotor speed and position with load conditions.