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:
Aug. 20, 2019
Filed:
Feb. 25, 2016
Hitachi-johnson Controls Air Conditioning, Inc., Minato-ku, Tokyo, JP;
Koji Tsukii, Tokyo, JP;
Atsushi Okuyama, Tokyo, JP;
Tsutomu Kurokawa, Tokyo, JP;
Masahiro Tamura, Tokyo, JP;
Kenji Tamura, Tokyo, JP;
Hitachi-Johnson Controls Air Conditioning, Inc., Tokyo, JP;
Abstract
A DC power supply unit is provided that allows for improving efficiency and reducing harmonic currents. A DC power supply unit includes: a bridge rectification circuit having diodes and MOSFETs; a reactor that is arranged between the AC power supply and the bridge rectifier circuit; a smoothing capacitor that is connected to an output side of the bridge rectifier circuit and smoothes a voltage; and a converter control unit that executes, based on predetermined threshold values, a diode rectification control that uses diodes and parasitic diodes of the MOSFETs, a synchronous rectification control that switches the MOSFETs in synchronization with a polarity of the voltage of the AC power supply, a partial switching control that repeats partially short-circuiting the reactor multiple times in a half cycle of the AC power supply, or a fast switching control that short-circuits the reactor at a predetermined frequency over a full AC cycle.