A simplified method to estimate the rotor position using the high frequency voltage signal injection

This paper presents a simple algorithm for estimation of the rotor position. The injected high frequency voltage is a sinusoidal voltage and is injected into the stator of a motor. An interior permanent magnet synchronous motor (IPMSM) has spatial saliency because d-axis inductance and q-axis inductance are different from each other. The injected high frequency voltage is influenced by saliency. Therefore, the rotor position is included in the stator current of the motor. The rotor position is estimated using filters but the estimated rotor position has error due to the time delay. Therefore, the proposed method decreases the number of filters and uses different synchronous reference frame transformation (SFT) to extract the rotor position error between the estimated value and actual value. The simulation results present the effectiveness of the proposed method by showing waveforms of the rotor speed and position with load conditions.