考虑网侧控制的DFIG静态稳定分析及参数优化

Research on small signal analysis of DFIG considering grid side converter controller and its parameters optimization

目前大多数双馈机组静态稳定简化模型不考虑网侧控制的动态过程,事实上网侧控制会直接影响系统静态稳定分析的结果。建立了含网侧控制动态特性的DFIG小干扰数学模型,计算结果与PSCAD仿真曲线的Prony分析结果能够较好吻合,而忽略网侧控制的动态会遗漏部分主导模态,影响静态稳定分析的正确性。针对DFIG接入产生的弱阻尼主导振荡模态,利用灵敏度分析法找出了最相关参数并给出优化方案,提升了系统的静态稳定裕度。

Most of the simplified small signal stability models of the doubly fed induction generator （DFIG） neglect the dynamic behavior of the grid side converter controller.However,grid side converter controller would affect the small signal stability analysis of the system.To solve this problem,the dynamic behavior of the grid side converter controller is considered in this proposed small signal model of DFIG.The eigenvalue analysis calculating results agree well with the Prony analysis results of PSCAD simulation curve,while several dominant mode shapes would be omitted if the grid side converter controller is neglected.In serious cases,it may affect the static stability analysis correctness.For the weak damping mode shapes,this paper adopts sensitivity analysis method to find the most relevant parameters and then put forward optimization scheme to enhance the system small signal stability concisely and effectively.