Comprehensive Reliability Assessment of Buck Quasi-Resonant Converter

This paper explores reliability assessment of various Quasi-Resonant (QR) buck DC-DC converters including zero current/voltage switching and half-wave/full-wave topologies. The impacts of output power, input voltage, output voltage, and time duration on the failure rate of each component are investigated, then overall reliability performance of each converter is evaluated. A detailed comparison is performed in which reliability metric of buck soft switching topologies is compared with each other as well as their parent hard switching topology. Eventually, mean time to failure of the converters is analyzed. This approach provides insightful information for selecting the topology or components for the purpose of designing QR converters. To achieve the reliability of these converters, first, the required equations to evaluate the effective factors on the reliability are obtained. Then reliability metric values are calculated for three cases in each of which a key parameter of the converters varies over a specified range.