Research on high efficient single-phase multi-stage interleaved Bridgeless PFC front-end for class-D amplifiers

In this paper, a 3.5kW single-phase high efficient interleaved Bridgeless PFC (IBPFC) is proposed for class-D amplifiers. This topology achieves a relatively higher efficiency in a wide output power range, which helps to reduce the energy consuming of the whole system. In addition, a detailed analysis is given to reach a compromise of IBPFC´s volume, efficiency and EMI reduction. A 3.5kW 2-stage IBPFC prototype covering universal input (from 85Vac to 265Vac) and with 390Vdc output is built and optimized. The experimental verifications show good Power Factor (PF) and excellent efficiency of 98.6% at 230Vac and a 2.22kW load.