Initial rotor position estimation by pulsating high-frequency voltage injection considering mutual inductance.

Pulsating high-frequency voltage injection is an effective method for estimating the initial rotor position for interior permanent magnet synchronous motors (IPMSMs). This method is based on the magnetic saliency of a motor rather than a back-electromotive-force (back-EMF) model. In addition, it is feasible when the motor is static or in low-speed operations. However, accurate estimation of the rotor position is realized on the assumption that the direct-axis and quadrature-axis of the motor are completely decoupled, which is not always satisfied. Then, the mutual inductance between the two axes introduces a theoretical error into the rotor position estimation. In this paper, the theoretical error of the rotor position estimation caused by mutual inductance is deduced. An improved initial rotor position estimation method is proposed to eliminate harmonic theoretical errors by injecting high-frequency voltage in the decoupling coordinate system. Finally, the effectiveness of this method is verified by experimental results. [ABSTRACT FROM AUTHOR]