AC-DC conversion device and voltage converter circuit

A method for converting an alternating current (AC) voltage into a direct current (DC) voltage via an AC-DC conversion device comprising an AC input terminal, an AC-DC conversion stage, a first DC terminal, a second DC terminal, a third DC terminal, and a partial power DC-DC converter, the method comprising:

• receiving the AC voltage at an AC input terminal of the AC-DC conversion device;
• converting the AC voltage into a first DC voltage by the AC-DC conversion device, wherein the first DC voltage is provided between the first DC terminal and the third DC terminal and corresponds to a voltage across a first capacitor;
• converting the AC voltage into a second DC voltage by the AC-DC conversion device, wherein the second DC voltage is provided between the second DC terminal and the third DC terminal and corresponds to a voltage across a second capacitor;
• outputting the second DC voltage at an output of the AC-DC conversion device;
• and
• regulating the second DC voltage across the second capacitor by the partial power DC-DC converter based on a required voltage across the output of the AC-DC conversion device by exchanging energy between the first capacitor and the second capacitor.