A New Control Method of Hybrid Active Filter Using a Feedforward Loop Tuned at 5th and 7th Harmonic Frequency

In this paper, we proposed a new control method for a three-phase hybrid active filter, consisting of a classical active filter connected in series with a passive filter. The non linear load is a diode rectifier feeding a (R, C) parallel load. The proposed method is based on two Self Tuning Filters placed in both feedback and feedforward loops dedicated to eliminate the 5^th and the 7^th harmonics frequency. The feedforward loop consists in two branches, one to remove the 5^th harmonic and the other one to remove the 7^th harmonic frequency. The use of Self Tuning Filters simplifies the control scheme by reducing the number of extraction filters used in classical feedback and feedforward loops. More, in this case, no Phase Locked Loop is necessary for the feedforward loop. The effectiveness of this new proposed scheme has been verified by computer simulation.