An Investigation of the Rotor Position Influence on the Broadband Phase Impedance - Application to SFRA Diagnosis

Sweep Frequency Response Analysis (SFRA) applied to rotating machines diagnosis and monitoring lacks of widespread industrial applicability up to this date. Several authors identify the rotor position influence as one of the main obstacles for an on-site and cost-effective diagnosis. This work provides a thorough investigation on how the rotor affects the broadband phase impedance of a Permanent Magnet Synchronous Machine (PMSM). The study is developed in several stages including analytical, Finite Element Analysis (FEA) and experimental measurements. The rotor field is identified as the main cause for the rotor position influence. In addition, the magnetic excitation of the stator coils and thus, the coil distribution, play a significant role on the broadband impedance variation.