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:
May. 08, 1990
Filed:
Jul. 12, 1989
Applicant:
Inventors:
Akira Horie, Katsuta, JP;
Yoshiji Jimbo, Katsuta, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02M / ;
U.S. Cl.
CPC ...
318811 ; 363 41 ;
Abstract
In a PWM-controlled, variable voltage/variable frequency inverter, a pulse mode, which is identified by a number of voltage pulses within one cycle of an output AC voltage of the inverter, is changed in accordance with a frequency of the output AC voltage and an output AC voltage factor, which is a ratio of an output AC voltage to be produced by the inverter at that time to a maximum value of the output AC voltage which can be produced under a then-present value of a voltage of a DC voltage source for the inverter.