A novel harmonic currents detection method based on rotating d-q reference frame for active power filter

This paper presents novel harmonic currents detection method based on rotating d-q reference frame, which can accurately extract harmonic and reactive currents of nonlinear loads under the conditions of asymmetric and distorted supply voltage. A predictive current control is proposed for active power filter (APF) to track reference currents. Two digital signal processor (DSP) based experimental prototypes are built. One is 5 kVA lab-based APF and the other is 150 kVA hybrid-type APF. The simulation and experimental results are given, which verify the effectiveness of the proposed methods.