An Improved Fully Soft Switched PWM Boost Converter

This work presents an improved fully soft switched boost converter (IFSS-BC) with an active snubber cell. In the presented converter, the snubber circuit provides soft switching operation of all semiconductors. The boost switch turns on with zero voltage transition (ZVT) and turns of with zero voltage switching (ZVS). The snubber switch turns on with zero current switching (ZCS) and turns off with ZVS. The boost diode turns off with ZCS and turns on with ZVS. All diodes in the snubber circuit work with soft switching. Besides, the current tension of the snubber switch is reduced by the soft switching energy transfer to the output. In the IFSS-BC, additional current and the voltage tension not occur. Soft switching operation of the semiconductors is continued for very wide load ranges. The detailed theoretical anlysis of the IFSS-BC is presented and the presented operation is verified with a prototype operating at 100 kHz with 800 W output power and 380 V output voltage.