The use of power Darlington transistors in an 40 kVA UPS system-an improved solution

Author

Quintas, A. ; Faria, J. ; Martins, A. ; Araujo, A. ; Silva, J.

Author_Institution

Autom. & Control Section, Porto Univ., Portugal

fYear

1989

fDate

1-5 Oct. 1989

Firstpage

974

Abstract

The use of power Darlington transistors for an inverter of a 40 kVA uninterruptible power supply (UPS) system is discussed, and the storage time, dead time, and switching aid network contributions to the total harmonic content of the output voltage are examined. A review of common switching aid circuits, for nominal and short-circuit conditions, is presented, and their limitations are discussed. A solution, conceived specifically for power Darlington transistors, is presented. The solution that fits the most relevant characteristics of this technology is analyzed regarding commutation under nominal conditions, commutation under short-circuit conditions, and contribution to harmonic distortion in the output voltage. Conclusions are drawn about the optimal switching frequency for this type of application. The discussion and conclusions are supported by experimental and simulation results.<>

Keywords

harmonics; power transistors; switching; uninterruptible power supplies; 40 kVA; UPS; commutation; dead time; harmonic distortion; inverter; optimal switching frequency; output voltage; power Darlington transistors; storage time; total harmonic content; uninterruptible power supply; Circuits; Harmonic distortion; Inductance; Magnetic separation; Power harmonic filters; Pulse width modulation inverters; Storage automation; Switching frequency; Uninterruptible power systems; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Industry Applications Society Annual Meeting, 1989., Conference Record of the 1989 IEEE

Conference_Location

San Diego, CA, USA

Type

conf

DOI

10.1109/IAS.1989.96609

Filename

96609