DFT-based Repetitive Control of a Series Active Filter Integrated with a 12-pulse Diode Rectifier

This paper considers the transient performance and stability of a recurrent DFT-based control method for a series active filter integrated with a 12-pulse diode rectifier. The control method targets specific harmonics and/or the negative sequence fundamental component of the supply current and is intended for use with non-sinusoidal/unbalanced supply voltages. The proposed control method is based on DFTs instead of the dq-method and a simple approach is used to account small frequency variations found in practical power systems.