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:
Jun. 03, 1980
Filed:
Mar. 02, 1978
Applicant:
Inventors:
Toshiaki Okuyama, Hitachi, JP;
Hiroshi Nagase, Hitachi, JP;
Yuzuru Kubota, Hitachi, JP;
Takamasa Hori, Ibaraki, JP;
Assignee:
Hitachi, Ltd., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02P / ;
U.S. Cl.
CPC ...
318716 ; 318822 ;
Abstract
An AC motor has polyphase stator windings connected to an AC bus and has polyphase rotor windings connected directly or through impedances to capacitors. The capacitances of the capacitors are selected so as to be such that the AC motor exhibits a small input impedance for a specific frequency to be eliminated, thereby preventing the power factor from being since the fundamental frequency is not affected in any way under a light load. As a result, harmonics can be eliminated without causing any excessive AC source voltage.