Signal injection method without torque ripple for stator winding temperature estimation of surface-mounted PMSM drive systems.

A signal injection method without torque ripple is presented to estimate the stator winding temperature of a surface-mounted permanent magnet synchronous machine (PMSM), where the temperature is estimated based on the stator resistance. First, the current signal (Δid*) is injected into the current control loop to produce DC current offsets used to calculate the stator resistance, where the injected signal cannot lead to extra torque ripple. Then the temperature can be obtained based on the relationship between the stator winding temperature and the stator resistance. Finally, the proposed method is validated by simulation and experimental results. In addition, no extra equipment is needed for the proposed method. [ABSTRACT FROM AUTHOR]