access icon free Dynamic analysis of DC–DC converter internal to an offshore wind farm

This study investigates the feasibility of integrating a single-switch active rectifier layout in an offshore wind farm. The proposed active rectifier topology consists of cascade connection of a diode-rectifier and a DC–DC boost converter. A DC collection grid is considered inside the wind farm, which supplies power to a land grid. Each wind conversion units within the DC collection grid includes a turbine, a generator, and an active rectifier. The DC–DC stage of the active rectifier allows regulating the frequency of generator, controlling the DC voltage to follow the reference signal, mitigating the distortion or ripple in the current signal, and maintaining the fault-ride through capability of the wind farm. The AC output signal from the wind-turbine-generators is converted to DC signal through a non-controlled full-bridge diode rectifier and a controlled DC–DC converter. The dynamic model of the DC–DC boost converter cascaded with the diode-rectifier is derived; and the contribution of pulse width modulation (PWM)-controller to the mitigation of signal variations is evaluated. The results prove consistency of the closed loop PWM-controller, which reduces significantly the gain of disturbances. The results are presented in the form of small-signal transfer functions and simulated using MATLAB software.

Inspec keywords: wind turbines; turbogenerators; PWM rectifiers; frequency control; wind power plants; voltage control; power grids; closed loop systems; offshore installations; network topology; PWM power convertors; power system faults; bridge circuits; DC-DC power convertors

Other keywords: generator frequency regulation; small-signal transfer function; DC-DC boost converter internal dynamic analysis; DC collection grid; DC voltage control; offshore wind farm; wind conversion unit; distortion mitigation; diode-rectifier cascade connection; wind turbine generator; disturbance gain reduction; single-switch active rectifier topology; pulse width modulation controller; fault-ride through capability; closed loop PWM-controller; signal variation mitigation

Subjects: a.c. machines; DC-DC power convertors; AC-DC power convertors (rectifiers); Frequency control; Wind power plants; Voltage control; Control of electric power systems

References

    1. 1)
    2. 2)
      • 25. Musasa, K., Siti, W.M., Jordaan, J.A.: ‘Harmonic spectrum measurement principles based on digital fault recorder (DFR) analysis’. Proc. third IASTED African Conf., Africa PES, Gaborone, Botswana, 6–8 September 2010.
    3. 3)
    4. 4)
      • 22. Marten, A.K., Westermann, D.: ‘Power flow participation by an embedded HVDC grid in an interconnected power system’. Third IEEE PES Innovative Smart Grid Technologies Europe (ISGT Europe), Berlin, 2012.
    5. 5)
    6. 6)
    7. 7)
    8. 8)
    9. 9)
      • 10. Yazdani, A., Iravani, R.: ‘Voltage-sourced converters in power systems: modelling, control, and applications’ (IEEE Press, John Wiley & Sons, Inc. Book, 2010).
    10. 10)
      • 9. Mohan, N., Undeland, T.M., Robbins, W.P.: ‘Power electronics: converters, applications, and design’ (John Wiley & Sons, Inc., 2003, 3rd edn.).
    11. 11)
    12. 12)
      • 15. Wakileh, G.J.: ‘Power system harmonics, fundamentals, analysis and filter design’ (Springer, New York, 2001).
    13. 13)
      • 16. Powell, L.: ‘Power system load flow analysis’ (Mc Graw-Hill Professional Engineering, New York, USA, 2004).
    14. 14)
      • 14. Erickson, R.W.: ‘Fundamentals of power electronics’ (Kluwer Academic Publishers, Secaucus, NJ, USA, 2000, 2nd edn.).
    15. 15)
      • 24. Musasa, K., Gitau, M.N., Bansal, R.C.: ‘Dynamic analysis of DC-DC converter internal to an offshore wind farm’. IET-RPG Conf., Italy, November 2014.
    16. 16)
      • 7. Gavrilovic, A.: ‘AC/DC system strength as indicated by short circuit ratios’. Int. Conf. on Transmission and Distribution System, London, UK, 17–20 September 1991.
    17. 17)
    18. 18)
      • 1. Max, L.: ‘Design and control of a DC collection grid for a wind farm’. PhD Thesis, Dep. of Energy and Environment, Chalmers University of Technology, Sweden, November 2009.
    19. 19)
    20. 20)
    21. 21)
      • 27. Hy-Line: ‘High voltage intelligent power modules’ (Mitsubishi Electric, 2008).
    22. 22)
    23. 23)
    24. 24)
    25. 25)
    26. 26)
    27. 27)
http://iet.metastore.ingenta.com/content/journals/10.1049/iet-rpg.2014.0420
Loading

Related content

content/journals/10.1049/iet-rpg.2014.0420
pub_keyword,iet_inspecKeyword,pub_concept
6
6
Loading