Shunt-series active power filter for rectifiers AC and DC sides

The authors present a feasibility study of a shunt-series active power filter to be used with three-phase thyristor controlled rectifiers. The proposed active filter is based on two active power units: one shunt filter connected to the AC side and one series filter connected to the DC side of the rectifier. The filters may have a common DC link and the shunt filter is controlled using the concepts of the instantaneous real and imaginary powers (p-q power theory). The series filter is controlled in such a way as to cancel the output voltage ripple of the rectifier. Digital simulation results obtained from an electromagnetic transient program (EMTP) are presented to validate this study. Experimental results obtained with a small-scale laboratory prototype consisting of shunt and series filter operating separately are also presented to show their benefits.