磁链控制型双馈风电机组及其弱电网阻尼优化策略  

Flux-controlled DFIG-based Wind Turbine and Its Damping Optimization Strategy in Weak Grid

作　　者：谢震[1] 李喆 冯艳涛 张兴[1] XIE Zhen;LI Zhe;FENG Yantao;ZHANG Xing(School of Electrical Engineering and Automation,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学电气与自动化工程学院,安徽省合肥市230009

出　　处：《电力系统自动化》2022年第24期132-141,共10页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51877063)。

摘　　要：区别于跟网型结构,采用构网型结构的双馈风电机组不存在电流环与锁相环的耦合,且具备一定的频率/电压主动支撑能力,因而更适合在弱电网下运行。针对双馈风电机组的构网型结构,提出一种磁链控制型双馈风电机组(FC-DFIG)构网方案,通过构建定子磁链外环-转子电流内环的双闭环结构实现对定子磁链矢量的幅相控制,进而调节并网功率。基于传输功率与定子磁链矢量的关系,提出FC-DFIG构网方案,并建立其小信号模型,证明该结构稳定可控。此外,针对弱电网下的低阻尼特性,基于定子d轴磁链微分前馈策略优化系统阻尼,理论和实验证明所提方案可以改善机组阻尼特性,有效提升FC-DFIG在弱电网下的稳定性。Being different from the grid-following structure, the doubly-fed induction generator(DFIG)-based wind turbine with a grid-forming structure has no coupling between the current loop and the phase-locked loop, and has a certain frequency/voltage active support ability, so it is more suitable for operation in the weak grid. Aiming at the grid-forming structure of DFIG-based wind turbines, a grid-forming scheme of flux-controlled DFIG(FC-DFIG) is proposed. The amplitude and phase control of the stator flux vector is realized by constructing a double closed-loop structure of stator flux outer loop and rotor current inner loop, and then the grid-connected power is adjusted. Based on the relationship between transmission power and stator flux vector, the gridforming scheme of FC-DFIG is proposed, and its small signal model is established to prove that the structure is stable and controllable. In addition, aiming at the low damping characteristics in the weak grid, the system damping is optimized based on the differential feedforward strategy of stator d-axis flux. Through theory and experiment, it is proven that the proposed scheme can improve the damping characteristics of the unit and effectively improve the stability of FC-DFIG in the weak grid.

关 键 词：弱电网 双馈风电机组 定子磁链幅相控制 阻尼优化 

分 类 号：TM315[电气工程—电机]