Experimental study and comparison of hybrid active filter with parallel active filter

The characteristics of the hybrid active filter, in which the L-C circuit is connected in series to an active filter, are analyzed. The VA rating of high switching frequency converter is notably reduced because of the L-C circuit used in the proposed hybrid active filter. An analytical method about the DC capacitor voltage, converter-rating etc. of hybrid active filter and pure parallel active power filter is presented in this paper, which shows the prominent advantages of hybrid active filter. The simulation results of the two kinds active filter are coincident with the theoretical analysis. Finally, results from a 50 kVA and a 100 kVA hardware prototype are presented to verify the prominent advantages of hybrid active filter and its good compensation characteristics.