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:
Jan. 31, 1989
Filed:
Feb. 29, 1988
Applicant:
Inventors:
Hiroshi Fujii, Chiba, JP;
Yuichiro Nagato, Chiba, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
363 41 ; 363 37 ; 363 97 ; 318811 ;
Abstract
A PWM inverter provided with a sinusoidal waveform generator circuit which produces modulated waves to switch the asynchronous operation into the synchronous operation when the output of a frequency commander commands a frequency greater than a predetermined value and when the sinusoidal waveform generator produces an output of a phase that is zero.