| Abstract |
This paper deals with Buck-Boost Zero-Voltage-Switching Quasi-Resonant Converters (BB-ZVS-QRC's). A simple procedure is introduced to generate six BB-ZVS-QRC's from the conventional Buck-Boost PWM converter, without the use of the Resonant-Switch concept. Two of the six circuit configurations generated were already reported in the literature. The equations describing converters operation are derived and with them the similiraties and differences among the six topologies are discussed, particularly from the point of view of component stresses. By employing state-plane technique, the constraints to ensure Zero-Voltage-Switching are defined for each topology. Some important experimental results are presented, from a laboratory prototype operating at resonant frequency of 1.60 MHz and maximum switching frequency of 1.11 MHz. The effect of the junction capacitance of the output rectifier diode on, component stresses and losses are also presented and experimentaly demonstrated. |
