Efficient resonant topology for DC-AC inversion with minimal use of high frequency switches

摘要

System and apparatus for power conversion. In one embodiment, the apparatus comprising a DC stage, comprising a resonant circuit, for generating a high-frequency resonant current; and an AC stage for converting a high-frequency current, generated from the high-frequency resonant current, to an AC output current, wherein the AC stage comprises: a pair of serially-connected switches for (i) passing, during a first half of a cycle of an AC line, a positive portion of the high-frequency current, and (ii) passing, during a second half of the cycle of the AC line, a negative portion of the high-frequency current; and an unfurling bridge for unfurling a current waveform, formed from the positive and the negative portions, to generate the AC output current, wherein the unfurling bridge is operated at a frequency on the order of three orders of magnitude lower than an operating frequency of the serially-connected switches.