Experimental evaluation of RFOC and DTC strategies for B6-VSI fed induction motor drives

In variable speed applications based on induction motor (IM) drives, two types of popular control strategies are distinguished: rotor flux oriented control (RFOC) and direct torque control (DTC). This paper investigates an experimental evaluation of four control strategies for two-level three-phase inverter fed IM drives, namely: (i) RFOC with current-controlled PWM, (ii) RFOC with voltage-controlled PWM, (iii) classical DTC, and (iv) bus-clamping DTC. The control strategies under consideration are firstly reviewed and therefore their control performances are analyzed and compared based on several experimental results. The comparative evaluation is carried out on the basis of numerous criteria: Torque and flux ripples, steady-state performance, dynamic response, parameter sensitivity, control sampling period, and algorithm complexity.