Abstract: Permanent magnet (PM) flux strength in a permanent magnet synchronous machine (PMSM) can be affected by operating conditions including thermal, mechanical, environmental and electrical stresses. Reduced flux strength, also called demagnetization, can lead to the degradation of the efficiency, performance and reliability of the machine and the drive system. A reliable PM strength, PM flux linkage, PM SOH, PM demagnetization detection method using the same inverter (i.e. motor drive) used to operate the PMSM is provided. The method comprises applying phase voltages to each of a plurality of motor leads of the PMSM with the PMSM at a stand-still condition; measuring current in each of the plurality of motor leads of the PMSM while applying the phase voltages thereto; and determining at least one of flux linkage, PM strength, PM SoH, or PM demagnetization based on a value of the current in at least one of the motor leads.