Controller saturation nonlinearity in doubly fed induction generator-based wind turbines under unbalanced grid conditions

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

6 Scopus Citations
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Author(s)

Detail(s)

Original languageEnglish
Pages (from-to)1602–1619
Journal / PublicationInternational Journal of Circuit Theory and Applications
Volume44
Issue number8
Online published16 Dec 2015
Publication statusPublished - Aug 2016
Externally publishedYes

Abstract

Doubly fed induction generator (DFIG) is widely used in wind energy generation systems due to its cost-effective, partially rated back-to-back power converters, variable rotor speed operation, and maximum wind power capture. The conventional design assumes balanced grid voltage and utilizes power protection for the power converters. The DFIG wind turbine is naturally one of the major components in distributed generations of the smart grid system. However, newly developed smart grid system is rich in unbalanced loads. This paper summarizes the limiter settings of controllers and explores the nonlinear behaviors of the DFIG-based wind power generation system with unbalanced loads. The generator rotor speed and an unbalanced load resistance are chosen as variation parameters. An emerging low-frequency linear-modulated oscillation at line second harmonic frequency with DC drifting is identified on the DC link voltage of the back-to-back power converters. In terms of second harmonic and the usually reported hazardous low-frequency oscillation, the saturation nonlinearity and over-modulation of the back-to-back power converter and its power flow are investigated and analyzed. The built-in detailed model of the DFIG wind energy generation system in Matlab with SimPowerSystems library is used in this study. Copyright © 2015 John Wiley & Sons, Ltd.

Research Area(s)

  • controller saturation, doubly fed induction generator, nonlinearity, over-modulation, unbalanced loads

Citation Format(s)

Controller saturation nonlinearity in doubly fed induction generator-based wind turbines under unbalanced grid conditions. / Li, Zhen; Wong, Siu-Chung; Tse, Chi K.; Liu, Xiangdong.

In: International Journal of Circuit Theory and Applications, Vol. 44, No. 8, 08.2016, p. 1602–1619.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review