PMSM diagnostics and prognostics - Evaluation of an on-line method based on high frequency current response

Sammanfattning: This thesis covers and evaluates a stator insulation fault detection method for Permanent Magnetised Synchronous Machines (PMSMs). The method could be implemented on-line and is based on using the power converter in an electric or hybrid vehicle to measure the State of Health (SoH) of the stator insulation of the PMSM. This is done through measurements of the high frequency current response that occurs when the PMSM is subjected to a voltage pulse from the power converter. The high frequency content of this current response is related to the parasitic capacitances of the PMSM and thereby also reflect the quality of the stator insulation. It is shown, in this thesis, that small impedance changes, corresponding to degradation and an early developing fault, can be detected with high repeatability and accuracy.