Use of extra degrees of freedom in multilevel drives

Author

BenAbdelghani, Afef ; Martins, Carlos A. ; Roboam, Xavier ; Meynard, Thierry A.

Author_Institution

Lab. d´´Electrotech. et d´´Electron. Ind., CNRS, Toulouse, France

Volume

49

Issue

5

fYear

2002

fDate

10/1/2002 12:00:00 AM

Firstpage

965

Lastpage

977

Abstract

Multilevel converters with series connection of semiconductors allow power electronics to reach medium voltages (1-10 kV) with relatively standard components. The increase of the number of semiconductors provides extra degrees of freedom, which can be used to improve different characteristics. This paper is focused on variable-speed drives and it is shown that with the proposed multilevel direct torque control strategy (DiCoIF) the tradeoff between the performances of the drive (harmonic distortions, torque dynamics, voltage step gradients, etc.) and the switching frequency of the semiconductors is improved. Then, a slightly modified strategy reducing common-mode voltage and bearing currents is presented.

Keywords

harmonic distortion; induction motor drives; insulated gate bipolar transistors; machine bearings; machine control; power convertors; state estimation; switching circuits; torque control; 1 to 10 kV; bearing currents; common-mode voltage reduction; degrees of freedom; delay estimation; fixed-frequency dynamic control; harmonic distortions; industrial power systems; insulated gate bipolar transistors; medium voltages; multilevel direct torque control strategy; multilevel drives; power electronics; semiconductors; series connection; state estimation; switching frequency; torque dynamics; variable-speed drives; voltage step gradients; Drives; Electric variables control; Error correction; Frequency; Induction machines; Inverters; Power electronics; Power system harmonics; Sampling methods; Torque control;

fLanguage

English

Journal_Title

Industrial Electronics, IEEE Transactions on

Publisher

ieee

ISSN

0278-0046

Type

jour

DOI

10.1109/TIE.2002.803183

Filename

1036746