Posicast-based digital control of the buck converter
Qi Feng
Nelms, R.M.
Hung, J.Y.
Dept. of Electr. Eng., Auburn Univ., AL, USA;
This paper appears in: Industrial Electronics, IEEE Transactions on
Publication Date: June 2006
Volume: 53,
Issue: 3
On page(s): 759- 767
ISSN: 0278-0046
INSPEC Accession Number: 8933237
Digital Object Identifier: 10.1109/TIE.2006.874418
Current Version Published: 2006-05-30
Abstract
The analysis, design, and microcontroller-based implementation of a digital controller using a Posicast element are presented for the buck converter. Posicast is a feedforward compensator that eliminates overshoot in system response, but the traditional approach is sensitive to variations in natural frequency. The new method described here reduces the undesirable sensitivity by using Posicast within a feedback loop. Compared to classical proportional-integral-derivative (PID) control, the new control results in lower noise in the control signal because the controller has a lower gain at high frequency. Furthermore, the authors' experiments indicate that the new controller is less sensitive to the inherent time delay associated with a digital controller for a dc-dc converter. The authors present a straightforward method to design controller parameters from the small-signal averaged model of the converter dynamics. Experimental results for a PID-controlled converter and Posicast-type controller are also compared.
Index
Terms
Available to subscribers and IEEE members.
References
Available to subscribers and IEEE members.
Citing Documents
Available to subscribers and IEEE members.