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. 02, 1993
Filed:
Sep. 13, 1990
Keijiro Sakai, Hitachiohta, JP;
Tunehiro Endo, Hitachiohta, JP;
Yuzuru Kubota, Hitachi, JP;
Takashi Ikimi, Hitachi, JP;
Nobuyoshi Mutoh, Katsuta, JP;
Mitsuyuki Honbu, Katsuta, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a control method and device for an AC motor, when transforming output power of a converter to AC power by an inverter and controlling the AC motor with the AC power, a source current value is determined from the value of an electric variable in the input or output side of the inverter, and the converter is controlled in accordance with the source current value. This makes the source current free from an influence of ripple components. Accordingly, even when the load of the AC motor is fluctuated abruptly, the required AC power can be applied to the converter so as to follow such fluctuations.