A Series Voltage Sag Compensator with Reduced Magnitude of Transformer Inrush Current

Voltage sags are found to be the key power quality problems faced by the industrial consumers. These sags frequently cause the disturbance in industrial manufacturing processes and result in substantial financial losses. In order to deal with such problems, a voltage sag compensator is often installed since it is among the most economical solutions to deal with sags to protect the sensitive loads. However, a problem of inrush transient current occurs as the series transformer gets energized to compensate the load voltage. This not only affects the critical load but also triggers the over-current mechanism of the series voltage sag compensator (SVSC). This paper proposes a SVSC with the reduced magnitude of transformer inrush current using a current controlled inverter. The proposed SVSC is validated using simulation results.