Use of DFIWG for Improvement of Voltage Stability Condition of a Power System

  • Durlav Hazarika
  • Ranjay Das
Original Contribution


This paper describes a method for improvement of voltage stability condition of a multi-bus power system by regulating reactive power generation at a Doubly Fed Induction Wind Generator (DFIWG). For this purpose, sensitivity relation between changes in voltage stability index at a bus with respect to change in reactive power generation of the DFIWG is derived. This relation is used to determine the required amount of change in rotor current of the DFIWG to improve the voltage stability index of the bus.


DFIWG Voltage stability Reactive power Rotor voltage 

List of Symbols


Number of buses in the system


Voltage magnitude of i th bus


Phase angle of bus voltage of i th bus


Real power injection at i th bus


Reactive power at i th bus


Total number of buses in the power system


Load flow Jacobian matrix


Voltage stability index for k th bus


Imaginary part of k th row and j th column element of bus admittance matrix


Sensitivity factor between change of voltage stability index and change of reactive power


Stator side d-axis voltage


Stator side q-axis voltage


Stator side a-phase voltage


Stator side b-phase voltage


Stator side c-phase voltage


Rotor side d-axis current


Rotor side q-axis current


Maximum value of rotor side d-axis current


Transformation matrix


Angular frequency of the system


  1. 1.
    IEEE/CIGRE, Joint task force on stability terms and definitions: “definition and classification of power system stability”. IEEE Trans. Power Syst. 19(3), 1387–1401 (2004)CrossRefGoogle Scholar
  2. 2.
    H. K. Clark, New challenges: voltage stability. IEEE Power Eng. Rev. 10, 33–37 (1990)Google Scholar
  3. 3.
    P. Kessel, H. Glavitsch, Estimating the voltage stability of a power system. IEEE Trans. Power Deliv. 1(3), 346–354 (1986)CrossRefGoogle Scholar
  4. 4.
    F. Gubina, B. Strmcnk, Voltage collapse proximity index determination using voltage phasor approach. IEEE Trans. Power Syst. 10(2), 788–793 (1995)CrossRefGoogle Scholar
  5. 5.
    A.K. Sinha, D. Hazarika, Comparative study of voltage stability indices in a power system. Int. J. Electr. Power Energy Syst 22(8), 589–596 (2000)CrossRefGoogle Scholar
  6. 6.
    O. Crisan, M. Liu, Voltage collapse prediction using an improved sensitivity approach. Electr. Power Syst. Res 28, 181–190 (1984)CrossRefGoogle Scholar
  7. 7.
    P.A. Lof, G. Anderson, D.J. Hill, Voltage stability indices of stressed power system. IEEE Trans. PWRS 8(1), 326–335 (1993)Google Scholar
  8. 8.
    A. Tiranuchit, R.J. Thomas, A posturing strategy against voltage instability in electrical power systems. IEEE Trans. PWRS 3(1), 87–93 (1989)Google Scholar
  9. 9.
    V. Ajjarapu, C. Christy, The Continuation power flow—a tool for steady state voltage stability analysis. IEEE Trans. Power Syst. 7(1), 416–423 (1992)CrossRefGoogle Scholar
  10. 10.
    B. Gao, G. K. Morison and P. Kundur, Voltage stability evaluation using modal analysis. in IEEE/PES 1991 summer meeting, San Diego, California, Paper 91 SM-O PWRS, (1991)Google Scholar
  11. 11.
    W. Leonhard, Control of Electrical Drives (Springer, New York, 2001)CrossRefGoogle Scholar
  12. 12.
    J.B. Ekanayake, L. Holdsworth, N. Jenkins, Comparison of 5th order and 3rd order machine models for doubly fed induction generator (DFIG) wind turbines. Electr. Power Syst. Res. 67(3), 207–215 (2003)CrossRefGoogle Scholar
  13. 13.
    R. Datta, V.T. Ranganathan, A method of tracking the peak power points for a variable speed wind energy conversion system. IEEE Trans. Energy Convers. 18(1), 163–168 (2003)CrossRefGoogle Scholar
  14. 14.
    R. Datta, V.T. Ranganathan, Variable-speed wind power generation using doubly fed wound rotor induction machine—A comparison with alternative schemes. IEEE Trans. Energy Convers. 17(3), 414–421 (2002)CrossRefGoogle Scholar
  15. 15.
    R. Datta and V. T. Ranganathan, Decoupled Control of Active and Reactive Power for a Grid-connected Doubly-fed Wound Rotor Induction Machine without Position Sensors. IEEE conference 1999, pp. 2623–2630Google Scholar
  16. 16.
    D. Hazarika, S. Bhuyan, S.P. Chowdhury, Avoiding risk of voltage instability in a power system through reactive power rescheduling and load shedding. Electr. Power Comp. Syst. 35(2), 169–187 (2007)CrossRefGoogle Scholar
  17. 17.
    S.N. Bhadra, D. Kastha, S. Banerjee, Wind Electrical Systems (Oxford University Press, New Delhi, 2005)Google Scholar

Copyright information

© The Institution of Engineers (India) 2017

Authors and Affiliations

  1. 1.Department of Electrical EngineeringAssam Engineering CollegeGuwahatiIndia
  2. 2.Department of Electrical EngineeringCentral Institute of TechnologyKokrajharIndia

Personalised recommendations