New space vector PWM method based on virtual flux vector for T-NPC Inverter

Abstract

This paper proposes a new SVPWM algorithm for operating the three-level TNPC topology. The idea of this algorithm is approximating as close as possible the locus of actual virtual flux vector and ideal one and minimizing the numbers of switching in one switching interval to improve the efficiency of the whole system. The virtual flux vector is monitored to determine the sector and the proper non-zero voltage vectors. The performance of the converter and the comparison of different modulation methods are analyzed. Simulation and experimental results show that the proposed method provides high efficiency.