A novel adaptive control approach for three-phase improved power quality converter under distorted and unbalanced AC mains

摘要

In this paper, a novel simplified control technique is proposed to control three-phase improved power quality converter for disturbed AC mains. The proposed technique is based on retransformation of Clarke transformation. The trajectory of reference vector is very important for SVM technique to obtain exact switching times. Due to disturbed supply in a three-phase system, the trajectory of reference vector gets affected which results in low input power factor, high input current THD and high ripple factor of the DC output voltage in power converters. In the proposed technique, PI operation is implemented for the retransformation of Clarke transformation. The modified Clarke transformation generates a required shape of the trajectory of reference vector so that the system performs satisfactorily even under disturbed AC mains. Moreover, the proposed scheme has the advantage of fast response and is simple enough to be implemented in a single-chip microcontroller. The simulation results are presented to demonstrate the effectiveness of the new proposed control technique.