Flying capacitor three-level converter and flying capacitor three-level buck-boost converter

Abstract

Disclosed is a flying capacitor three-level converter, including a plurality of circuit units, wherein each of the plurality of circuit units includes: an input capacitor; a bridge arm, electrically connected with the input capacitor in parallel, wherein the bridge arm includes a first switch, a second switch, a third switch and a fourth switch electrically and sequentially connected in series; and a flying capacitor unit, wherein the flying capacitor unit includes a first capacitor and a second capacitor, and the first capacitor and the second capacitor are electrically connected in parallel and electrically connected with a series branch in parallel, and the series branch includes the second switch and the third switch; wherein the input capacitor, the first switch, the first capacitor and the fourth switch form a first switching loop, and the second capacitor, the second switch and the third switch form a second switching loop.