Zero-Voltage Transition of Dual-Switch Based PWM Boost Converter

Use of conventional boost converter cell as zero-voltage transition (ZVT) cell for dual-switch based boost converter gives soft-switching operation for switches but at the expense of increased current stress. In this paper, an attempt is made to reduce the current stress by using modified ZVT-cell. This cell uses all the elements used in conventional boost cell but they all are connected in series across the switched-capacitor cell. The switched-capacitor cell based dual-switch converter along with the modified ZVT cell attains better voltage gain at moderate duty ratio values together with soft-switching of the devices. Also, the diodes turn-OFF when their voltage becomes close to zero leading to zero current switching operation. Principle of operation is explained through key waveforms and theoretical analysis is formulated by examining various zones that the converter exhibits in one switching cycle. For concept demonstration, simulation results are given first and finally experimental observations of prototype are included for comparison purpose.