The Impact of Stator Resistance on Initial Rotor Position Detection for PMSM Using High-Frequency Voltage Injection

In this article, the impact of stator resistance on initial rotor position detection for permanent magnet synchronous motor (PMSM) using a high-frequency (HF) voltage injection method is analyzed comprehensively. Theoretical derivation shows that the stator resistance appears as a phase shift term in the error signal for position estimation using the rotating HF voltage injection (RHFVI) method. The accuracy of initial rotor position detection is, therefore, degraded, and an obvious average error occurs when R/L_d is greater than 200. On the contrary, using the pulsating HF voltage injection (PHFVI) method, the stator resistance appears as amplitude term in the position error signal, the initial rotor position can be estimated accurately, and there is nearly no dc bias error at a steady state. Finally, experimental data validates the effectiveness of the theoretical analysis in the article.