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. 05, 2019
Filed:
Nov. 17, 2017
Renesas Electronics Corporation, Tokyo, JP;
Minoru Kurosawa, Tokyo, JP;
Kichiya Itagaki, Tokyo, JP;
Renesas Electronics Corporation, Tokyo, JP;
Abstract
A motor driving device and a motor system that can reduce a torque ripple of a motor are provided. The current control loop detects a drive current of the motor, detects an error between the detected value of the drive current and a current indication value as a target value of the drive current, and determines the duty of the PWM signal reflecting the error concerned. The back EMF phase detector detects the phase of a back electromotive force of each phase in the motor. The torque correction unit calculates a first torque correction coefficient of a periodic function based on the phase variations in the three phases of the back electromotive force, and corrects the current indication value superimposing the first torque correction coefficient on the current indication value.