Optimal Reserve Allocation to Maximize Kinetic Energy in a Wind Power Plant

  • Yoon, Gihwan ;
  • Lee, Hyewon ;
  • Lee, Jinsik ;
  • Yoon, Gi-Gab ;
  • Park, Jong Keun ;
  • Kang, Yong Cheol
  • Received : 2015.02.24
  • Accepted : 2015.06.05
  • Published : 2015.09.01


Modern wind generators (WGs) are forced or encouraged to participate in frequency control in the form of inertial and/or primary control to improve the frequency stability of power systems. To participate in primary control, WGs should perform deloaded operation that maintains reserve power using speed and/or pitch-angle control. This paper proposes an optimization formulation that allocates the required reserve to WGs to maximize the kinetic energy (KE) stored in a wind power plant (WPP). The proposed optimization formulation considers the rotor speed margin of each WG to the maximum speed limit, which is different from each other because of the wake effects in a WPP. As a result, the proposed formulation allows a WG with a lower rotor speed to retain more KE in the WPP. The performance of the proposed formulation was investigated in a 100-MW WPP consisting of 20 units of 5-MW permanent magnet synchronous generators using an EMTP-RV simulator. The results show that the proposed formulation retains the maximum amount of KE with the same reserve and successfully increases the frequency nadir in a power system by releasing the stored KE in a WPP in the case of a disturbance.


Deloaded operation;Frequency support;Kinetic energy;Primary control;Wake effect;Wind power plant


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