Mitigation of power supply disturbance in electronic loads

Abstract

An alternate power supply guarantees the performance of loads during voltage disturbances in the normal supply. It is proposed to implement a quick change over of the power supply of single-phase electronic loads from the faulty phase to a healthy phase in a 3-phase system. Super capacitors maintain the dc voltage during the period of disturbance. A zigzag transformer may also be used to rebuild a balanced 3-phase load voltage by isolating the faulty phase from the load. Both the 3-phase and single-phase loads may be supplied with the rated voltage during the period of disturbance. Use of a static transfer switch reduces the change over time to 0.02 second.