The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 22, 2014
Filed:
Feb. 07, 2012
Yuichiro Nozaki, Hitachinaka, JP;
Tetsuo Kojima, Hitachinaka, JP;
Masafumi Makino, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a DC power supply in which a DC power source and a transformer are connected via a power conversion circuit and a secondary winding of the transformer is connected to a load via a rectifier diode bridge and a filter circuit to supply power to the load, a resonance reactor is provided on an output side of the transformer, a resonant switch circuit including a parallel circuit of a diode and a semiconductor switch and a resonant capacitor is connected in parallel to the rectifier diode bridge and a snubber circuit including a snubber capacitor, a snubber diode and a diode for discharge is connected to a serial resonant circuit including the resonance reactor and the resonant capacitor in the resonant switch circuit to absorb a surge voltage.