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:
Jul. 08, 2025
Filed:
Sep. 14, 2021
Oriental Motor Co., Ltd., Tokyo, JP;
Kei Kozakai, Tsukuba, JP;
Makoto Morimoto, Tsukuba, JP;
ORIENTAL MOTOR CO., LTD., Tokyo, JP;
Abstract
A stepping motor driver which drives a stepping motor according to a position angle command includes: a current detector that detects a phase current; an inverter that applies a current to a winding; and a control unit that controls the inverter. The control unit includes: a phase current coordinate transformer that transforms the phase current to generate a dp-axis detection current and a qp-axis detection current; a torque correction command generator that generates a torque correction command according to a torque correction waveform for suppression of torque fluctuation; a torque correction command coordinate transformer that transforms the torque correction command into a dp-axis component and a qp-axis component to generate a dp-axis torque correction component and a qp-axis torque correction component; an adder that superposes the dp-axis torque correction component and the qp-axis torque correction component respectively on a dp-axis fundamental current command and a qp-axis fundamental current command to generate a dp-axis current command and a qp-axis current command; and a control command generator that compares the dp-axis detection current and the qp-axis detection current respectively with the dp-axis current command and the qp-axis current command and applies a control command to the inverter.