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:
Dec. 30, 2025
Filed:
Jun. 06, 2022
Hitachi, Ltd., Tokyo, JP;
Hiroshi Kamizuma, Tokyo, JP;
Akihiko Kanouda, Tokyo, JP;
Yuuichi Mabuchi, Tokyo, JP;
Kimihisa Furukawa, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A plurality of power conversion units, a current sensor that detects a current at an output terminal of the power conversion unit, and a control unit that measures a frequency component in a predetermined frequency range of a current detected by the current sensor are included, the power conversion unit includes an AC/DC converter that outputs AC power at an input terminal to an output terminal, a smoothing capacitor that is connected in parallel to the output terminal and smooths an output voltage, and a variable resistance switch connected between one end of the smoothing capacitor and one end of the output terminal, the control unit controls a resistance value of the variable resistance switch according to a magnitude of a predetermined frequency component detected by the current sensor, and the output terminals of the plurality of power conversion units are connected in parallel to constitute output terminals.