Full Feedforward of the Output Voltage to Improve Efficiency for Envelope-Tracking Power Supply Using Switch-Linear Hybrid Configuration

Author

Xi, Huan ; Jin, Qian ; Ruan, Xinbo ; Xiong, Xiaoling

Author_Institution

Aero-Power Sci-tech Center, Nanjing Univ. of Aeronaut. & Astronaut., Nanjing, China

Volume

28

Issue

1

fYear

2013

fDate

Jan. 2013

Firstpage

451

Lastpage

456

Abstract

A synchronous rectification buck converter in parallel with a Class AB linear amplifier is presented in this paper to construct an envelope-tracking (ET) power supply. To eliminate the influences of the output voltage on the linear amplifier output current, a full feedforward of the output-voltage scheme with two feedforward terms is proposed in this paper, which can counteract all the two load admittances of the linear amplifier, respectively, consequently decreasing the linear amplifier output current substantially. An ET power supply prototype with 100-kHz sine-wave tracking, 5-15 V output voltage, and 75-W-peak output power is fabricated and tested in the lab. The experimental results are well in agreement with the theoretical analyses, and the system efficiency is improved significantly.

Keywords

feedforward amplifiers; power convertors; power supply circuits; ET power supply prototype; class AB linear amplifier; efficiency improvement; envelope-tracking power supply; frequency 100 kHz; full feedforward; load admittances; output-voltage scheme; power 75 W; sine-wave tracking; switch-linear hybrid configuration; synchronous rectification buck converter; voltage 5 V to 15 V; Power supplies; Pulse width modulation; Switches; Switching converters; Switching frequency; Voltage control; Envelope tracking (ET); feedforward; power amplifier (PA); switch-linear hybrid configuration;

fLanguage

English

Journal_Title

Power Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0885-8993

Type

jour

DOI

10.1109/TPEL.2012.2200109

Filename

6202702