Robust loop-shaping controller for load frequency control of an uncertain deregulated power system

  • Arlene Davidson RosalineEmail author
  • S. Ushakumari
Original Contribution


Load frequency control forms an essential component of automatic generation control which helps to maintain the power system frequency constant while maintaining the tie-line power flow with neighbouring areas at scheduled values for an interconnected power system. With deregulation, the structure of electric power industry is changed thoroughly with multiple bilateral transactions taking place in a competitive market environment. In the changed scenario, the conventional controllers are no more capable of satisfying the control requirements. It is hence that robust controllers are suggested for load frequency control which can handle the uncertainties that are rampant in the system. In this paper, a robust H loop-shaping controller is used as load frequency controller for a two-area deregulated power system with non-reheat thermal power plants. Analysis of the system performance is done for all contract cases relevant to deregulated power systems. The system behaviour towards different cost functions is also investigated to demonstrate the robustness of the controller.


Deregulation Contract Unilateral Bilateral Contract violation Loop shaping 



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Copyright information

© The Institution of Engineers (India) 2019

Authors and Affiliations

  1. 1.Department of Electrical EngineeringCollege of Engineering TrivandrumTrivandrumIndia

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