An emergency frequency control method based on efficient coordination between generator tripping and power regulation for wind power integrated system

Abstract

Wind generators with integrated inertia control can autonomously regulate active power in response to frequency variations within the power system. Generator tripping is often necessary to address frequency increases during significant grid disturbances. This tripping alters the adjusLEle power range of the wind generator and frequency characteristics of the power system, impacting power regulation capacity and modifying the required generator tripping power (GTP). Precise frequency control in wind power integrated systems is challenging due to the inability to accurately quantify frequency security conditions. To address this, the synthetic power regulating speed (SPRS) is deduced to characterize regulation capability. The ranges of required GTP and SPRS are modeled under constraints including maximum frequency deviation, rate of frequency change, and the frequency regulating capacity of wind farms. A novel concept of the frequency dynamic security domain is introduced, accounting for the interplay among generator tripping, power regulation, and frequency characteristics. This approach includes identifying generator tripping locations and determining the required GTP by establishing the frequency dynamic security domain. Additionally, an emergency frequency control method that coordinates generator tripping and power regulation is proposed. Simulations show that this method minimizes generator tripping while avoiding frequency threshold exceedance, thus preserving power regulation capability.