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:
Oct. 14, 2008
Filed:
Sep. 30, 2003
Manabu Yoshimura, Tokyo, JP;
Toshiyuki Kaitani, Tokyo, JP;
Manabu Yoshimura, Tokyo, JP;
Toshiyuki Kaitani, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A CPU calculates, based on a frequency command value for driving a motor and on a state quantity of the motor, an output-voltage command value in which only the phase advances while amplitude is constant in each calculation period, without reducing the calculation period. An ASIC reflects the output-voltage command value in a triangular wave signal in a time-series order to compare with each other, and outputs a PWM signal to a switching circuit. Thus, a waveform of an output voltage is made close to a sine wave irrespective of an output frequency being high or low, and a processing load of the CPU is reduced.