US 12,113,455 B2 · Multilevel conversion circuit having flying capacitor and method for pre-charging the same

Abstract

Multilevel conversion circuit having a flying capacitor and method for pre-charging the same are provided. The multilevel conversion circuit includes: a first bridge arm including a plurality of switches connected in series; a second bridge arm including a plurality of switches connected in series and a flying capacitor group, midpoints of the two bridge arms connected to a power supply and an inductor to form a series branch; a DC bus capacitor to which the two bridge arms are connected in parallel; a first voltage clamping module connected between a first end of the flying capacitor group and a first end of the DC bus capacitor; and a second voltage clamping module connected between a second end of the flying capacitor group and a second end of the DC bus capacitor.

Claims30

Dependent claims

A multilevel conversion circuit having a flying capacitor, comprising:

a first bridge arm comprising a plurality of switches connected in series;
a second bridge arm comprising a plurality of switches connected in series and a flying capacitor group, wherein a midpoint of the second bridge arm and a midpoint of the first bridge arm are connected to a series branch, wherein the series branch is defined by a power supply and an inductor;
a DC bus capacitor connected in parallel to the first bridge arm and the second bridge arm;
a first voltage clamping module between a first end of the flying capacitor group and a first end of the DC bus capacitor;
a second voltage clamping module between a second end of the flying capacitor group and a second end of the DC bus capacitor;
an auxiliary power supply connected to the DC bus capacitor, and
a controller coupled to the auxiliary power supply and the plurality of switches of the second bridge arm, the auxiliary power supply provides power for the controller.

4 more elements

A method for pre-charging a multilevel conversion circuit having a flying capacitor, comprising:

providing a multilevel conversion circuit, comprising:
a first bridge arm comprising a plurality of switches connected in series;
a second bridge arm comprising a plurality of switches connected in series and a flying capacitor group, wherein a midpoint of the second bridge arm and a midpoint of the first bridge arm are connected to a power supply and an inductor to form a series branch;
a DC bus capacitor connected to both the first bridge arm and the second bridge arm in parallel;
a first voltage clamping module connected between a first end of the flying capacitor group and a first end of the DC bus capacitor;
a second voltage clamping module connected between a second end of the flying capacitor group and a second end of the DC bus capacitor;
an auxiliary power supply connected to the DC bus capacitor, and
a controller coupled to the auxiliary power supply and the plurality of switches of the second bridge arm, the auxiliary power supply provides power for the controller;
powering the multilevel conversion circuit;
charging the DC bus capacitor through the corresponding switches of the first bridge arm and the corresponding switches of the second bridge arm.

7 more elements

Dependencies are inferred from the claim text.

Multilevel conversion circuit having flying capacitor and method for pre-charging the same

Life of this patent

Multilevel conversion circuit having flying capacitor and method for pre-charging the same

Life of this patent

Abstract

Claims30