Comparison of Different Compensation Methods of the Mutual Inductance for Self-Sensing Control

A mutual inductance between the d-axis and q-axis leads to a stationary rotor position estimation error in a self-sensing control (SSC). In this paper, two methods to compensate the rotor position estimation error are compared. It is found that by considering the mutual inductance in an estimator for SSC based on numerical optimisation, the mutual inductance can be used as an source of information. Thus, the critical point, where the difference between the d-axis and q-axis inductances vanishes, can be operated with high position estimation quality in the presence of a mutual inductance. This is not possible with other methods for compensating the rotor position estimation error which are widely used in the literature.