Design of closed loop audio power amplifiers by means of an accurate model of vented box loudspeakers

Author

González-Espín, F.J. ; Figueres, E. ; Garcerá, G. ; Sandia, J.

Author_Institution

Camino de Vera S/N, Valencia

fYear

2007

fDate

2-5 Sept. 2007

Firstpage

1

Lastpage

9

Abstract

The purpose of this paper is to analyze the stability of closed loop switching power amplifiers using an accurate model of a loudspeaker installed in a commonly used bass reflex enclosure instead of the purely resistive model that can be used with a Zobel network. The model takes into account the electrical-mechanical-acoustical parameters of the transducer as well as the voice-coil loudspeaker´s non-linear behavior, avoiding stability problems when trying to compensate for the output filter stage, thus obtaining better THD figures. This model has been experimentally tested and then used to design a regulator for Voltage-Mode Control method by means of MATLAB software. The regulator has been simulated using a full-bridge power converter along with the proposed model of the transducer.

Keywords

audio-frequency amplifiers; closed loop systems; loudspeakers; mathematics computing; power amplifiers; power convertors; stability; transducers; voltage control; MATLAB software; closed loop audio power amplifiers; electrical-mechanical-acoustical parameters; full-bridge power converter; stability; switching power amplifiers; transducer; vented box loudspeakers; voice-coil loudspeaker; voltage-mode control; Filters; Loudspeakers; MATLAB; Mathematical model; Power amplifiers; Regulators; Software testing; Stability analysis; Transducers; Voltage control; Efficiency; Modelling; Simulation;

fLanguage

English

Publisher

ieee

Conference_Titel

Power Electronics and Applications, 2007 European Conference on

Conference_Location

Aalborg

Print_ISBN

978-92-75815-10-8

Electronic_ISBN

978-92-75815-10-8

Type

conf

DOI

10.1109/EPE.2007.4417717

Filename

4417717