Improved control strategy on single-phase PWM current source inverter with pulse area modulation

In recent years, single-phase PWM current source bridge inverters using active power switches in series with a diode have attracted special interest in place of voltage-fed PWM inverters in utility-interactive power systems. On the other hand, this type of inverter has a significant disadvantage to be improved in practical applications, in that the output current delivered from this inverter includes a large amount of harmonic components when the smoothing DC reactor is not large enough to sufficiently eliminate the ripple components in the DC current. Thus, this paper presents an effective pulse area modulation control strategy to eliminate the harmonic current components in the AC side of single-phase current source PWM inverters. The principle of the proposed control strategy for this inverter system is described, and its simulation results are introduced and evaluated.