Determination of Rotor-Angle Dependent, Differential Inductances of a Synchronous Reluctance Machine for Different Model Structures

This paper addresses the determination of rotor-angle dependent, differential inductances of a permanent magnet assisted synchronous reluctance machine by evaluating the current response to voltage pulses. It explains how the same measurement data can be used to determine the inductances for different structures of the machine model in the abc- and dq-reference frame and compares the results. In particular, the influence of the magnetic anisotropy on the machine’s star-point potential during the evaluation of the data in the abc-system is discussed. Based on the rotor-angle dependent results in the dq-system, the paper demonstrates how the measurement data can be used to identify design-related harmonics of the machine and how the results can be converted between different models.