Space Vector PWM Techniques for B3-VSI Fed Three-Phase IM Drives

This paper investigates two space vector pulse width modulation (SVM) techniques dedicated to the control of an open-loop induction motor (IM) drives fed by a three-switch three-phase inverter (TSTPI), also known as delta- or B3-voltage source inverter (B3-VSI). The B3-VSI performs a DC to three-phase AC conversion by employing only three power switch devices rather than six ones as in the classical six-switch three-phase inverter (B6- VSI). The reduction of the number of switch devices involves a potential increase in reliability and lifetime of the power conversion system. Nevertheless, the B3-VSI generates only three active voltage vectors and one zero voltage vector, which makes the development of various relevant SVM techniques a complicated task. The two proposed SVM methods allow the application of three voltage vectors for each switching period considering different vector switching sequences. Several differences between the developed SVM techniques are discussed and compared based on simulation results.