Reliability Comparison of a Dual Boost and a Triangular Current Mode Resonant-Transition PFC Converter Topology

In PFC rectifier systems for telecom applications, a general trend towards higher efficiency and also higher power density converter designs can be observed. Due to the passive components and the switching losses, a compromise between power density and efficiency has to be made. A possibility to overcome this limitation are soft-switched converter systems, which, however, often come along with a higher component count, a higher component stress and/or a more complex control. These issues might impair the system reliability although the lower losses might reduce the thermal stress of the components. Therefore, in this work the reliability of a relatively simple, hard switched dual boost PFC rectifier and a soft switched triangular current mode PFC is evaluated and the components influencing the reliability most are identified. The evaluation is based on the prediction models given in IEC TR 62380.