Design of active low pass filters to reduce harmonic current emission

The growing development of distributed generation and storage devices has allowed the growth of micro-grids in low voltage and medium voltage grids. This caused the increase of voltage harmonics with high frequency in LV and MV grids. This aspect is most important to right operations of the VSI-current controlled. This paper investigated the effect of the voltage high frequency ripple in the point of common coupling for the current total harmonic distortion, hence to improve the power quality have been used active low pass filters for the feedforward grid voltages in the current inner loop. Furthermore, some types of active low pass filters and their performances have been compared.