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:
Mar. 21, 2017
Filed:
May. 09, 2016
Fuji Electric Co., Ltd., Kawasaki-shi, JP;
Tetsuya Kawashima, Matsumoto, JP;
FUJI ELECTRIC CO., LTD., Kawasaki-Shi, JP;
Abstract
An output voltage error detection unit outputs an auxiliary winding voltage generated across an auxiliary winding having the same number of turns as a secondary winding a certain period after a secondary conduction period starts. A correction amount calculation unit calculates a secondary voltage drop caused by a secondary current flowing in the conduction period based on a primary current flowing when the conduction period starts and outputs a calculation result as a correction amount. A reference voltage generation unit generates a reference voltage by adding the correction amount to the output voltage. A control unit generates a feedback signal to minimize the error between the auxiliary winding voltage obtained after a certain delay period and the reference voltage. A PWM signal generation unit controls a PWM signal based on the feedback signal, adjusts switching of the switching element, and maintains the output voltage at a constant level.