New hybrid parallel active filter configuration minimising active filter size

l h e mthors propose 11 new topology for a hybrid pai-allel active filter that can rwdicr rediice the active filter (inverter) power rating. The basic idea is to install the active filter in parallcl with the passive filter inductor. One iidvaiit;igc of this is that the passive fitter ciin operirte by itselr if the inverter is in the high-impedance mode. This nieans that the passive filter CRII operatc without Ihc aid of the active filter. Another adviintage is that, because the significant portion of fundamental and harmonic components flows through the passive filter, the current loading to the inverter is rcduccd greatly. This contributes to reducing the cost of the expensive inverter, and, hence, this makcn tlic application of a hybrid active power filter more feasible. Through computer siinulations and experiments, the authors liave verified the effectiveness of the proposed topology.