Selective harmonic currents suppressing applied to a three-phase shunt active power filter based on adaptive filters

This paper proposes a selective strategy used to generate the harmonic current references, which are employed in the control loops of a three-phase active power filter (APF). By applying the aforementioned selective strategy, the selection of the harmonic components that will be suppressed by means of the filter is allowed. The proposed strategy comprises of an algorithm based on the synchronous reference frame. In addition, it uses adaptive filters in order to carry out the harmonic components selection. The APF topology is implemented by using a four-leg inverter, which is mathematically modelled in two-phase stationary reference frame (αβ0-axes). Due to the inherent decoupling in the αβ0-axes, proportional and integrative controllers are used in each one of the referred coordinates, allowing the individual control of the compensation currents. The SRF-based algorithm is mathematically analyzed, as well as experimental results are presented in order to validate the theoretical development.