Current Summation-Based Inductance Asymmetry Compensation for High Frequency Signal Injection Sensorless Control of Dual Three-Phase IPMSMs

This paper proposes a simple inductance asymmetry compensation method for minimizing the second-order harmonic current responses and the corresponding position errors in high frequency signal injection sensorless controlled dual three-phase interior permanent magnet synchronous machines (IPMSMs). It is found that the second-order harmonics of HF current responses in two sets of dual three-phase windings due to self-inductance asymmetry have opposite phase angles in the double
dq
control method. Thus, a simple current summation-based position error compensation method including an online calculation technique of harmonic amplitude ratio is proposed. The proposed compensation method can not only suppress the second-order position error effectively but also maintain a high signal-to-noise ratio of the sensorless control system. It is validated by experiments under different inductance asymmetry conditions.