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. 26, 1993
Filed:
Jul. 19, 1991
Kabushiki Kaisha Toshiba, Kanagawa, JP;
Abstract
In an inverter in which six switching elements of an inverter main circuit is controlled to be turned on and off under a switching pattern in which a voltage space vector composed of adjacent two of six fundamental voltage vectors out of phase from one another by an electrical angle of .pi./3 and a zero vector figures a circular locus so that a three-phase substantially sinusoidal voltage is obtained, a three-phase PWM signal generating device includes a circuit in which two switching patterns of the same kind are formed before and after the formation of the switching pattern corresponding to the zero vector, respectively, a circuit in which the switching pattern corresponding to the zero vector is held for half of its holding time when the voltage space vector passes an intermediate phase position between the two adjacent fundamental voltage vectors, and a circuit in which when the magnitude of the command voltage vector exceeds the region of a circular locus figured by the fundamental voltage vector, the command voltage vector is converted to a new command voltage vector so as to meet the region.