Identification of Critical Wind Farm Locations for Improved Stability and System Planning

With wind penetration levels increasing in power systems, it will be necessary for system planners to have a better understanding of their systems and make best use of the mitigation tools that already present in the system. Particularly, in order to maintain rotor angle stability with high penetrations of wind generation, it will be critical for system planners to utilize the built-in reactive power controls of modern variable speed wind turbines. This paper develops a comprehensive system planning methodology that assesses the characteristics of a given system and identifies nodes that are critical to the rotor stability of the system. This is achieved by utilizing small-signal analysis to identify wind farm locations that participate significantly from an electro-mechanical perspective and implemented by using the built-in controls of the turbine to control voltage at these nodes. By controlling the voltage at these specific locations, the magnitude and damping of oscillatory modes that arise following a loss of a generator can be significantly improved. Furthermore, it will demonstrate that the selective implementation of reactive power control does not degrade the voltage stability of the system for a large system disturbance.