The goal of developing AC-DC converters with Isolation and Power Factor Correction feature in arnsingle power processing stage and without a mandatory full-bridge rectifier has for years eludedrnPower Electronics researchers. Present AC-DC converters operated from a single-phase ac line arernbased on conventional PWM switching method and process the power through at least three distinctrnpower processing stages: full-bridge rectifier followed by Boost PFC converter and another cascadedrnisolated Full-Bridge DC-DC converter stage, which together use a total of 14 switches and threernmagnetic components resulting in corresponding efficiency, size and cost limitations.rnThe new Hybrid Switching Method enables new Single-Stage AC-DC converter topology, the TruernBridgeless PFC Converter* consisting of just three switches and a single magnetic component albeitrnat a much higher efficiency approaching 98% and having a 0.999 power factor and 1.7% totalrnharmonic distortion.rnThree-Phase Rectifier~* consisting of three such Single-Phase Rectifiers~* takes for the first time a fullrnadvantage of Tesla’s three-phase transmission system to convert constant instantaneous input powerrnof a three-phase system directly to a constant DC output power, albeit isolated at high switchingrnfrequency, with near unity power factor (0.999), low total harmonic distortion (1.7%), smaller size and lower cost but at ultra high efficiency of 98%.
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