New modulation strategy for three-phase current source inverters

Abstract

This paper proposes a new regular sampled pulse width modulation (PWM) for three-phase current source inverters. The theoretical basis of the proposed modulation strategy is described, including dwell time calculations and switching sequence selection. Thisstrategy is well suited for digital implementation, and enjoys all the flexibilities and degree of freedoms as in space vector modulation. In addition, it ensures a minimum number of switching transitions per fundamental cycle, unlike other PWM methods. It is therefore promising for high-power medium-voltage applications. The validity of the proposed modulation strategy has been confirmed using simulation and experimentation. To furthermore substantiate the superiority of the proposed modulation strategy against other PWM methods, its performance is compared to sinusoidal PWM, selective harmonic elimination, and space vector modulation.