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. 29, 2012
Filed:
Mar. 06, 2007
Hajime Takahashi, Kitakyushu, JP;
Mitsujiro Sawamura, Kitakyushu, JP;
Hajime Takahashi, Kitakyushu, JP;
Mitsujiro Sawamura, Kitakyushu, JP;
Kabushiki Kaisha Yaskawa Denki, Fukuoka, Tokyo, unknown;
Abstract
There is provided a PWM inverter capable of preventing a phase error from occurring in generating a PWM signal even in the case where a carrier wave frequency is not sufficiently higher than a signal wave frequency. A PWM signal generating section () includes a phase adjusting section () configured to advance a phase of the signal wave by adding, to a signal wave, a delay component of the PWM signal with respect to the signal wave, the phase delay component being involved by digital control. Furthermore, in a case where the carrier wave frequency is changed, the phase delay component with respect to the signal wave is updated in synchronism with the timing of change of the carrier wave frequency.