Dynamic Aggregation Method of Wind Farms with Virtual Synchronous Generator-Controlled Wind Turbines

Abstract

The frequency and voltage dynamic processes of each wind turbine in the existing wind farm are different, and the available aggregation model of wind farms mainly focuses on the steady-state output power, lacking an effective dynamic aggregation mechanism. Wind turbines usually adopt the virtual synchronous generator method (VSG) to simulate the external characteristics of the traditional synchronous generator. Its frequency dynamic response is mainly affected by the virtual inertia and damping parameters, and the excitation regulator parameters determine the voltage dynamic response. Therefore, the aggregation method of the traditional synchronous generator is also applicable to such wind turbines. Firstly, the dynamic characteristics of the points of wind farms’ point of common coupling (PCC) are discussed. Then, the dynamic aggregation method of the VSG-wind farms is proposed based on the Kuramoto (KM) model and the small signal analysis of the wind turbines. Finally, a wind farm consisting of multiple VSG-wind turbines under disturbances is simulated in PSCAD/EMTDC to verify the effectiveness of the proposed dynamic aggregation method.