Harmonic computation technique suitable for active power filters

The design and implementation of a novel method for reference generation that is applied to active power,filters (APFs) is introduced in this paper. The proposed reference generation performs harmonic detection based on the Goertzel algorithm. The method computes both the module I-1 and the phase phi of the signal, with minimum computation overhead. This makes the method suitable for APFs or other applications that require harmonic detection. A comparison analysis between the discrete Fourier transform and the proposed method is carried out. The proposed reference generator is implemented using a digital signal processor and tested with waveforms from typical load currents. Experimental results are obtained under both stationary and transient states.