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:
Jan. 14, 1997
Filed:
Mar. 31, 1995
Stanley Canter, Phoenix, AZ (US);
Ronald Lenk, Sunnyvale, CA (US);
Space Systems/Loral, Inc., Palo Alto, CA (US);
Abstract
A multi-slice power converter (10) employs a digital circuit (22) to generate phase-delayed pulse width modulated (PWM) signals, which results in the duty cycle of the PWM signals having only a certain number of possible values. The quantization of the duty cycle is shown to result in two types of instabilities which are unique to power converters having a digital control loop, in addition to the conventional analog-type of instabilities. This invention provides novel methods and apparatus for stabilizing the digital control loop of the power converter through the use of a periodic dither signal having a frequency that is less than the PWM frequency and greater than a bandwidth frequency of the converter. The dither signal functions to effectively increase the number of possible duty cycles by a factor given by the ratio of the dither frequency to the bandwidth frequency.