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:
Feb. 04, 2025
Filed:
Dec. 08, 2022
Nsk Ltd., Tokyo, JP;
Takayuki Kobayashi, Tokyo, JP;
Kyosho Uryu, Tokyo, JP;
NSK LTD., Tokyo, JP;
Abstract
A current detection device includes a current detection unit configured to detect current flowing through a switching element of a lower-side arm; a correction value calculation unit configured to calculate an offset correction value, based on a detection value of the current detected by the current detection unit in a period during which the switching element off during PWM control, and to hold and update the calculated offset correction value; and a correction unit configured to correct, by the offset correction value held by the correction value calculation unit, the detection value of the current detected by the current detection unit in a period during which the switching element is on. The correction value calculation unit is configured to not update the offset correction value in a case where a duty ratio of the PWM control is equal to or less than a duty ratio lower limit value.