Patent ID: 7184287

Claim:
A lossless clamping circuit for clamping a reverse voltage over two terminals of a power element of a power converter, wherein said power converter comprises a transformer having a secondary winding electrically connected to a full-wave rectifier circuit, and said full-wave rectifier circuit comprises a first rectifying diode, a second rectifying diode, an output filtering inductor, and an output filtering capacitor, comprising: two clamping diodes having two anodes electrically connected to each other to form a common-anode terminal and two cathodes electrically connected to two terminals of said secondary winding of said transformer; a first clamping capacitor having a first terminal electrically connected to a cathode of said first rectifying diode and a second terminal electrically connected to said common-anode terminal; a second clamping capacitor having a first terminal electrically connected to a connecting node of said output filtering inductor and said output filtering capacitor, and a second terminal electrically connected to said common-anode terminal; and a converter circuit having an input terminal electrically connected to said second clamping capacitor and an output terminal for offering a power sources comprising: an energy feedback inductor; an energy feedback switch; and an energy feedback diode.