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. 14, 1994
Filed:
Jan. 26, 1993
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 41 ; 318811 ;
Abstract
The present invention relates to a control apparatus of a three-level inverter and intends to provide a control apparatus of simplified construction which can suppress a fluctuation in neutral point voltage effectively. Only a third harmonic component which is particularly large in the fluctuation in neutral point voltage is suppressed, a third harmonic component for suppression has a ratio of amplitude to that of a fundamental wave and a phase which are set to be constant regardless of the inverter frequency, and this third harmonic component is applied to a command of the fundamental wave.