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:
Oct. 25, 2022
Filed:
Jan. 17, 2018
Hitachi Automotive Systems, Ltd., Hitachinaka, JP;
Katsuhiro Hoshino, Hitachinaka, JP;
Takafumi Hara, Tokyo, JP;
Masaru Yamasaki, Tokyo, JP;
Yosuke Tanabe, Tokyo, JP;
Masanori Watanabe, Tokyo, JP;
HITACHI ASTEMO, LTD., Hitachinaka, JP;
Abstract
An object of the present invention is to effectively reduce vibration or noise caused by a motor. An inverter circuitgenerates an alternating current from a direct current supplied from a direct current power supplyby using a plurality of IGBTswhich are switching elements, supplies the generated alternating current to a motor, and drives the motor. This alternating current includes a fundamental harmonic current corresponding to a rotational speed of the motor, and a harmonic current of a switching operation of the IGBTs. A controllercontrols a second phase such that a first phase and the second phase are not superimposed on each other at a predetermined motor rotational speed, the first phase being a phase of an excitation force cyclically produced in the motorby the fundamental harmonic current, and the second phase being a phase of an excitation force cyclically produced in the motorby the harmonic current.