A new space vector based control method for UPS systems powering nonlinear and unbalanced loads

In this paper a new real time space vector based control strategy is presented for 3-phase UPS systems powering nonlinear and unbalanced loads. The proposed control strategy generates the inverter reference and gating signals in closed loop and guarantees high quality output voltages at the load terminals. The approach, which is implemented on a DSP, adapts to a wide variation of nonlinear and unbalanced load conditions without specific knowledge of output filter (LC) component values. Analysis and experimental results on a 10 kVA system are presented. The results show that the output voltage is restored at heavy nonlinear and unbalanced load.