Title :
Adaptive prediction in digitally controlled buck converter with fast load transient response
Author :
Lee, Albert Ting Leung ; Chan, Philip Ching Ho
Author_Institution :
Dept. of Electron. & Comput. Eng., Hong Kong Univ. of Sci. & Technol., Hong Kong, China
Abstract :
An adaptive prediction scheme based on linear extrapolation for digitally controlled voltage-mode buck-type switching converter is presented. A major drawback of conventional digitally controlled switching converters is bandwidth limitation due to the additional phase lag in the digital feedback control loop. By predicting the future error voltage, the ADC sampling time delay is compensated in order to achieve a higher bandwidth even with a modest sampling rate. Both simulation and measurement results show that the output voltage settling time of the digitally controlled buck converter is reduced by as much as 28% with the proposed adaptive prediction. The fastest settling time in response to a 600mA load transient is around 15μs, approaching the transient response of the state-of-the-art analog-based controller.
Keywords :
analogue-digital conversion; digital control; extrapolation; power convertors; switching convertors; transient response; ADC sampling time delay; adaptive prediction; analog-based controller; current 600 mA; digital feedback control loop; digitally controlled voltage-mode buck-type switching converter; fast load transient response; phase lag; Bandwidth; Control systems; Extrapolation; Finite impulse response filter; Load modeling; Transient analysis; Voltage control; Adaptive prediction; IIR filter; adaptive FIR filter; buck converter; digital controller;
Conference_Titel :
Control and Modeling for Power Electronics (COMPEL), 2012 IEEE 13th Workshop on
Conference_Location :
Kyoto
Print_ISBN :
978-1-4244-9372-2
Electronic_ISBN :
1093-5142
DOI :
10.1109/COMPEL.2012.6251747