A mathematical analysis for PMSM sensorless sliding mode observer induced harmonics due to dead time and inverter non linearities

The dead time along with the other inverter non-idealities are known to distort the inverter output voltage. This affects the performance of all electrical drives at the low and medium speed range resulting into inacceptable performance. Sensorless drives are the most affected ones with this phenomenon compared to the other electrical drives. This paper proposes a quantitative mathematical analysis to the motor's current harmonics induced due to the dead time and inverter non linearity. The mathematical analysis is validated using simulations.