Sensorless speed vector-controlled induction motor drives using new random technique for inverter control

In the last decade, the features of random PWM techniques have been demonstrated for v/f controlled induction motor drive system. In this paper, the advantages and special features of the newly developed random technique for inverter control are highlighted and demonstrated by experimental results of a sensorless vector-controlled induction motor drive system. It is shown that the new random inverter control technique indeed has some advantages over other irregular-sampled random techniques, including easy incorporation with a vector-controlled drive system and significant reduction of computations. Experimental results from a DSP-based sensorless vector-controlled drive system are presented in the paper confirming the theoretical analysis, software and hardware design.