基于变工况等效模型和最优紧急功率控制的直驱风电场次/超同步振荡抑制方法OA

The dynamic interaction between various power electronic devices and power grids in modern power systems can lead to serious sub/super-synchronous oscillation issues.Due to the insufficient real-time performance of controller parameter/structure modification,current oscillation suppression methods mostly employ direct wind farm tripping strategy,which exacerbate grid impacts and exhibit poor economy.Therefore,this paper proposes a sub/super-synchronous oscillation suppression method for direct-driven wind farm based on variable operating condition equivalent model and optimal emergency power control.Firstly,an equivalent mathematical model is established by characterizing direct-driven wind farm admittance under multiple operating conditions as functions of operational variables.Based on the impedance method,a method for determining the controllable domain of direct-driven wind farm power adjustment is proposed with the objective of mitigating oscillation.Within this domain,the oscillation suppression problem is formulated as a multi-objective optimization problem that simultaneously considers economic efficiency and suppression effectiveness,and an emergency power control strategy is proposed for sub/super-synchronous oscillation suppression.The proposed method does not require modifying converter control parameters or structures,and can achieve oscillation suppression through optimal emergency power control while minimizing power loss.Finally,a simulation model based on actual multiple wind farms is analyzed to verify the effectiveness and economy of the proposed method,as well as its advantages over existing methods.