A novel high efficiency UPS using improved inverter and DC to DC converter

The uninterruptible power supply (UPS) presented combines a rectifier of high input power factor, a DC/DC power converter and a pulsewidth-modulated (PWM) inverter. However, in the inverter circuit, because a divided choke snubber was devised, short circuit failure can be avoided without giving the drive pulse of switching element a dead time period. Also because an LD snubber was designed, the current surge and the voltage surge do not occur. The performance of the switched snubber, the effectiveness of the LD snubber and of the divided choke snubber were verified by the experiments. Experimental results of testing these schemes are reported.<<ETX>>