基于定子虚拟阻抗的双馈风电机组虚拟同步控制策略

Virtual Synchronous Control Strategy of DFIG-based Wind Turbines Based on Stator Virtual Impedance

随着可再生能源的渗透率越来越高,分布式电源面临多重挑战,虚拟同步发电机技术模拟同步发电机运行机制,成为有效解决方法之一。以双馈风电机组为研究对象,研究分析其虚拟同步控制策略,使双馈风电机组具有更大的惯性和频率支撑能力。内环采用改进型双馈风电机组定子电压、转子电流双闭环控制结构,并且建立定子电压控制模型及发电机输出阻抗模型。针对并网时功率存在的耦合问题,采用基于自适应的定子虚拟阻抗控制策略,实现了双馈风电机组并网功率的解耦。最后,通过实验验证了所提方法的有效性。

With the increasing penetration of renewable energy connected to the grid,distributed power supply is facing multiple challenges.The virtual synchronous generator technology simulates the operating mechanism of synchronous generator,which becomes one of the most effective solutions.Taking the doubly-fed induction generator（DFIG）based wind turbines as the research object,the virtual synchronization control strategy is studied and analyzed.And the virtual synchronous control model is established to make the DFIG-based wind turbines have greater inertia and the ability of supporting frequency and voltage.The improved double-closed-loop control structure of stator voltage and rotor current for the DFIG is proposed,the stator voltage control model and the output impedance model are established as well.According to the problem of power coupling connected to the grid,the DFIG based on the adaptive stator virtual impedance control strategy helps realize the power decoupling.Finally,the experiment verifies the validity of the proposed method.