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:
Nov. 26, 2024
Filed:
Oct. 21, 2020
Tmeic Corporation, Chuo-ku, JP;
Shinya Suzuki, Tokyo, JP;
Shunsuke Tobayashi, Tokyo, JP;
TMEIC Corporation, Chuo-ku, JP;
Abstract
A motor drive system of the embodiment includes a power converter, a state detector, a frequency calculator, a frequency correction command generator, a drive amount limiter, and a speed controller. The power converter drives a motor by PWM control. The state detector detects a drive state of the motor. The frequency calculator detects a size of a specific frequency component which fluctuates according to the drive state by using an index value indicating the drive state. The frequency correction command generator generates a correction command of a carrier frequency used for the PWM control on the basis of a detected result of periodic fluctuation of the drive state. The drive amount limiter limits a drive amount of the motor. The drive amount limiter adjusts an upper limit value of a size of a current caused to flow through windings of the motor in a direction in which the upper limit value is lowered from a predetermined upper limit current value when the carrier frequency is searched for in a direction in which the carrier frequency is increased. The speed controller generates a current reference based on a speed command value and a rotor speed of the motor according to the limitation.