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:
Aug. 26, 2003
Filed:
Feb. 20, 2002
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
In a power supply system for converting the output of a DC power supply having an earth capacitance to AC power, an input voltage from an input-voltage detector and an intermediate voltage from an intermediate-voltage detector are input to an input-ripple controller. The latter calculates the difference between ripple voltages of the two voltages. The input-ripple controller adjusts the size of a ripple command value, which indicates the ripple current that is to be input to a converter circuit, so as to null the difference between the ripple voltages. Furthermore, using a ripple reference waveform having a DC level, the input-ripple controller generates a ripple current waveform so as to null the average value of a full-wave rectified waveform synchronized to the output of an inverter circuit, and outputs the generated ripple current waveform to an output calculator. The output calculator adds the DC current command from the input-voltage controller and the ripple current waveform from the input ripple controller to thereby generate an output current waveform, which is output to a converter circuit driver.