Compensating the island network voltage unsymmetricity with DTC-modulation-based power conditioning system

An algorithm for compensating island network voltage unsymmetricity with a direct torque control modulation-based scalar-controlled power conditioning system is introduced and experimentally verified. The proposed method consists of two separate stages where at first the unsymmetricity is detected and then a compensating negative-sequence system is calculated. Experimental results show that the proposed method fully compensates the voltage unsymmetricity resulting from unbalanced load. Both the magnitude and the phase angle unsymmetricity are compensated.