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:
Mar. 01, 2016
Filed:
May. 29, 2014
Kobelco Construction Machinery Co., Ltd., Hiroshima-shi, JP;
Sinfonia Technology Co., Ltd., Minato-ku, JP;
Akira Nakazumi, Hiroshima, JP;
Yusuke Kamimura, Hiroshima, JP;
Hiroyuki Suminaga, Tokyo, JP;
Takeshi Tomizaki, Tokyo, JP;
Hideaki Moriya, Tokyo, JP;
KOBELCO CONSTRUCTION MACHINERY CO., LTD., Hiroshima-shi, JP;
SINFONIA TECHNOLOGY CO., LTD., Minato-ku, JP;
Abstract
An object of the present invention is to provide an inverter device for driving an electric motor, which allows control stability and efficiency to be ensured over a wide region of the speed of the electric motor. The inverter device includes a rotational-speed detection section which detects a rotational speed of the electric motor, a carrier-frequency calculation section which calculates a carrier frequency on the basis of the detected rotational speed, and a carrier-frequency switching section which switches, on the basis of the calculated carrier frequency, the carrier frequency used for performing PWM control on the electric motor. The carrier-frequency calculation section calculates, as the carrier frequency, a frequency increased with an increase in the electric-motor rotational speed detected by the rotational-speed detection section.