An analysis and design of a star delta transformer in series with active power filter for current harmonics reduction

The analysis and design of a star delta transformer in series with active power filter linked to grid lines are carried out. The development of active power filter which consists of voltage reference, triangular generator to generate pulse width modulation with half inverters is simulated. The current injection network of half inverter in series with three phase of a star delta transformer which is interconnected to grid lines is also discussed. It is observed that the reduction of harmonics at grid lines was significantly reduced. The simulation results show that the total harmonic distortions are reduced within range of 45% - 50% and 97% - 99% at distributions and neutral lines respectively. Also, the distortions of sinusoidal waveform at grid lines were improved.