A power-efficient transconductance amplifier for wide-band high current calibrations

Author

Lavric, H. ; Voncina, D. ; Zajec, P. ; Nastran, J.

Author_Institution

Fac. of Electr. Eng., Ljubljana Univ., Slovenia

Volume

1

fYear

2003

fDate

10-12 Dec. 2003

Firstpage

631

Abstract

In the paper a transconductance amplifier capable of accurate amplifying currents from 1 mA up to 60 A rms within the frequency range from 40 Hz to 70 Hz with or without the presence of higher harmonics components is presented. Its sophisticated topology consists of a supreme control loop and an inner hybrid power amplifier with an output transformer. The hybrid power amplifier, which acts as a self-oscillating system, is composed of a superior three-stage class AB linear power amplifier and an inverter. The latter provides a full load current while the former filters the waveform ripple. In this way a power efficient system is obtained whose efficiency at a full output power is some 90%.

Keywords

feedback; feedforward; invertors; operational amplifiers; power amplifiers; power system harmonics; 1 mA to 60 A; 40 to 70 Hz; class AB power amplifier; current amplification; filters; harmonic components; hybrid power amplifier; inverter; linear power amplifier; output transformer; power efficient system; power efficient transconductance amplifier; self oscillating system; supreme control loop; waveform ripple; wide band high current calibrations;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Technology, 2003 IEEE International Conference on

Print_ISBN

0-7803-7852-0

Type

conf

DOI

10.1109/ICIT.2003.1290409

Filename

1290409