A single stage soft-switched AC/DC power factor corrected converter with galvanic isolation

Abstract

This paper describes a single-stage AC/DC Power Factor Correction (PFC) converter with galvanic isolation, and an active-clamp circuit is used to achieve zero-voltage-switching (ZVS) for both main and auxiliary switches. The ZVS operation principle of the system is illustrated in detail. Simulation and experimental results based on a 85 kHz, 3000 W prototype circuit show that the proposed converter has low component count, galvanic isolation, simple control, high power factor and high conversion efficiency in a wide load range.

A single-stage bridgeless ZVS AC/DC converter for power-factor-correction applications

“…The input current is in phase with the input voltage and its shape is a sinusoidal waveform. It can be observed that the measured current THD value of the proposed bridgeless converter is only 2.93% and it is lower than the converter in [9], the output voltage keeps at 400 V.…”

“…Simulation and experimental prototypes of the proposed ZVS bridgeless converter and the ZVS converter proposed in [9] were built to verify and compare the feasibility of the converter. The key components of the proposed converter are specified in Table I.…”

“…4 and Fig. 5 show the simulation and experimental waveforms of input voltage, input current and output voltage at the rated output power of 3000 W of two different topologies proposed in [9] and in this paper separately. The input current is in phase with the input voltage and its shape is a sinusoidal waveform.…”

“…A single-stage AC/DC isolated converter based on active-clamp technique is proposed in [9], it can realize the ZVS for both main and auxiliary switches, but it still needs a diode bridge rectifier and high conduction loss problem still remains. In an effort to maximize the power supply efficiency, considerable research efforts have been directed toward designing bridgeless PFC circuits.…”

Multiloop interleaved control for three-level buck converter in solar charging applications

“…They are divided into isolated [3] and nonisolated topologies. Isolated converters such as flyback or isolated cuk [9] converter are suitable for high conversion ratio applications, however these topologies have the problems of low conversion efficiency, high voltage stress, high switching losses and significant electromagnetic interference. Nonisolated DC-DC topologies [2,3,4,7] have the advantage of simple structure, and they are suitable for improving conversion efficiency and reducing the cost of the system.…”