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:
Apr. 08, 2025
Filed:
Jun. 26, 2023
Nidec Powertrain Systems Corporation, Kanagawa, JP;
Yasuhiro Shirai, Kanagawa, JP;
NIDEC POWERTRAIN SYSTEMS CORPORATION, Kanagawa, JP;
Abstract
A control device for a three-phase motor includes a drive circuit that converts DC power supply voltage into three-phase AC voltage and supplies the three-phase AC voltage to the three-phase motor, a first voltage detection unit that detects terminal voltage of three phases of the three-phase motor, and a control unit that detects a point at which a first voltage value, which is a detection value of the terminal voltage, intersects a predetermined zero-cross determination level as a zero-cross point, and controls the drive circuit based on a detection result of the zero-cross point. The control unit corrects the first voltage value by multiplying the first voltage value by a first coefficient inversely proportional to an output duty ratio with respect to the three-phase motor in a case where the output duty ratio is equal to or less than a predetermined threshold.