1 / 23

Harmonic Analysis of a DFIG for a Wind Energy Conversion System

Harmonic Analysis of a DFIG for a Wind Energy Conversion System. Lingling Fan, Ph.D., P.E. Assistant Professor Dept. Electrical Engineering University of South Florida Tampa, FL 33620 Linglingfan@usf.edu April 20, 2010. 2010 IEEE Transmission & Distribution Conference and Exhibition

keola
Download Presentation

Harmonic Analysis of a DFIG for a Wind Energy Conversion System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Harmonic Analysis of a DFIG for a Wind Energy Conversion System Lingling Fan, Ph.D., P.E. Assistant Professor Dept. Electrical Engineering University of South Florida Tampa, FL 33620 Linglingfan@usf.edu April 20, 2010 2010 IEEE Transmission & Distribution Conference and Exhibition New Orleans, LA

  2. Outline • Objective • Principle • Case studies • Rotor injection • Unbalanced stator conditions • Conclusion

  3. Objective • Develop a steady-state circuit to give quantitative analysis for harmonics in DFIG • The work is useful for understanding of • DFIG behavior during non-sinusoidal rotor injection • DFIG under unbalanced grid conditions (fault ride through)

  4. fm Doubly Fed Induction Generator Ps RSC AC/DC GSC DC/AC Pr = sPs

  5. A generalized circuit for harmonic analysis in DFIG

  6. Case study 1 – non-sinusoidal rotor injection

  7. Frequency components in rotor voltage and stator current • Stator currents • (6n+1)fr+fm, -(6n-1)fr+fm,

  8. Electromagnetic torque • Interaction of stator and rotor currents Ex: Is1, Ir2  torque (60- (-120 +36)) = 144 Hz = 6*24 Hz  6fr Is1, Ir3  torque (60- (168 +36)) = -144 Hz = -6*24 Hz  6fr

  9. Torque +

  10. Case study 2 – unbalanced stator conditions • Rotor injection – programmable power source –sinusoidal 3-phase • Stator phase a resistance is reduced

  11. Analysis Unbalanced stator currents Positive sequence (fe) Negative sequence (-fe) Zero sequence Rotor currents Ir: fe-fm=sfe Ir: -fe-fm=-(2-s)fe s: slip = 1-fm/fe fm: electric frequency corresponding to rotating speed. fe: nominal frequency 60 Hz (stator) – 50 Hz (rotating speed) = 10 Hz -60 Hz (stator) – 50 Hz (rotating speed) = -110 Hz

  12. Torque • Te1 Te2 – dc components • Te3, Te4 – pulsating components 120 Hz

  13. Reference frames Pos. Neg. Sequences can be separated by a dc filter!

  14. Extraction scheme

  15. Lab setup

  16. Case 3 – Grid interconnected DFIG

  17. Simulation results

  18. Confirm simulation results with the analysis

  19. Conclusion • This paper develops • A generalized steady-state DFIG circuit for harmonic analysis • A systematic method to compute torque by computing the interactions of stator and rotor currents • The sequence network based on DFIG pos, neg circuits which facilitates the analysis under unbalanced stator conditions.

More Related