Under thermal stresses a PMSM motor exhibits malfunctioning due to demagneti- zation of permanent magnets, occurs at the rotor side and variation of winding resistance at stator side. This research work is focused on the effect of winding resistance variation. It is observed that as the temperature increases, it increases the winding resistance which eventually reduces the phase currents and ultimately the torque of an Electric Machine (EM) derates. In order to manage ther- mally derated torque, sliding mode control (SMC) scheme is designed, simulated and implemented. After validating the efficacy of the proposed control scheme in simulation environment, it is verified experimentally on an PMSM drive controlled by Labview and ARM Cortex based microcontroller. Results shows that SMC is more effective and efficient in catering winding resistance variations due to the elevated temperature.
