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. 21, 1997
Filed:
Aug. 23, 1996
Keiji Iwata, Kawasaki, JP;
Michihisa Murasato, Kawasaki, JP;
Kenichi Tanigawa, Kawasaki, JP;
Sadaharu Tamoto, Kawasaki, JP;
Nippon Steel Corporation, Tokyo, JP;
Yutaka Electric Mfg. Co. Ltd., Kanagawa, JP;
Abstract
An inverter for DC/AC conversion includes an inverter bridge controlled by a PWM controller. The inverter has a first control loop for performing PWM control in accordance with the difference between the instantaneous AC value of an inverter output and an amplitude of waveform data read out from an AC waveform memory. The inverter also has a second control loop for multiplying the amplitude value of the waveform data by a coefficient adjusted on the basis of the error between the means AC current or voltage value of the inverter outputs and a target control value, and performing PWM control in accordance with waveform data having the adjusted amplitude. By using a delta scheme of finely increasing/decreasing at a time the coefficient by which waveform data is multiplied, an inverter with a high control precision and high stability can be obtained.